FFmpeg
avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include <errno.h>
31 #include "libavutil/samplefmt.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avutil.h"
34 #include "libavutil/buffer.h"
35 #include "libavutil/cpu.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/frame.h"
39 #include "libavutil/hwcontext.h"
40 #include "libavutil/log.h"
41 #include "libavutil/pixfmt.h"
42 #include "libavutil/rational.h"
43 
44 #include "version.h"
45 
46 /**
47  * @defgroup libavc libavcodec
48  * Encoding/Decoding Library
49  *
50  * @{
51  *
52  * @defgroup lavc_decoding Decoding
53  * @{
54  * @}
55  *
56  * @defgroup lavc_encoding Encoding
57  * @{
58  * @}
59  *
60  * @defgroup lavc_codec Codecs
61  * @{
62  * @defgroup lavc_codec_native Native Codecs
63  * @{
64  * @}
65  * @defgroup lavc_codec_wrappers External library wrappers
66  * @{
67  * @}
68  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
69  * @{
70  * @}
71  * @}
72  * @defgroup lavc_internal Internal
73  * @{
74  * @}
75  * @}
76  */
77 
78 /**
79  * @ingroup libavc
80  * @defgroup lavc_encdec send/receive encoding and decoding API overview
81  * @{
82  *
83  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
84  * avcodec_receive_packet() functions provide an encode/decode API, which
85  * decouples input and output.
86  *
87  * The API is very similar for encoding/decoding and audio/video, and works as
88  * follows:
89  * - Set up and open the AVCodecContext as usual.
90  * - Send valid input:
91  * - For decoding, call avcodec_send_packet() to give the decoder raw
92  * compressed data in an AVPacket.
93  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
94  * containing uncompressed audio or video.
95  *
96  * In both cases, it is recommended that AVPackets and AVFrames are
97  * refcounted, or libavcodec might have to copy the input data. (libavformat
98  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
99  * refcounted AVFrames.)
100  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
101  * functions and process their output:
102  * - For decoding, call avcodec_receive_frame(). On success, it will return
103  * an AVFrame containing uncompressed audio or video data.
104  * - For encoding, call avcodec_receive_packet(). On success, it will return
105  * an AVPacket with a compressed frame.
106  *
107  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
108  * AVERROR(EAGAIN) return value means that new input data is required to
109  * return new output. In this case, continue with sending input. For each
110  * input frame/packet, the codec will typically return 1 output frame/packet,
111  * but it can also be 0 or more than 1.
112  *
113  * At the beginning of decoding or encoding, the codec might accept multiple
114  * input frames/packets without returning a frame, until its internal buffers
115  * are filled. This situation is handled transparently if you follow the steps
116  * outlined above.
117  *
118  * In theory, sending input can result in EAGAIN - this should happen only if
119  * not all output was received. You can use this to structure alternative decode
120  * or encode loops other than the one suggested above. For example, you could
121  * try sending new input on each iteration, and try to receive output if that
122  * returns EAGAIN.
123  *
124  * End of stream situations. These require "flushing" (aka draining) the codec,
125  * as the codec might buffer multiple frames or packets internally for
126  * performance or out of necessity (consider B-frames).
127  * This is handled as follows:
128  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
129  * or avcodec_send_frame() (encoding) functions. This will enter draining
130  * mode.
131  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
132  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
133  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
134  * - Before decoding can be resumed again, the codec has to be reset with
135  * avcodec_flush_buffers().
136  *
137  * Using the API as outlined above is highly recommended. But it is also
138  * possible to call functions outside of this rigid schema. For example, you can
139  * call avcodec_send_packet() repeatedly without calling
140  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
141  * until the codec's internal buffer has been filled up (which is typically of
142  * size 1 per output frame, after initial input), and then reject input with
143  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
144  * read at least some output.
145  *
146  * Not all codecs will follow a rigid and predictable dataflow; the only
147  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
148  * one end implies that a receive/send call on the other end will succeed, or
149  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
150  * permit unlimited buffering of input or output.
151  *
152  * This API replaces the following legacy functions:
153  * - avcodec_decode_video2() and avcodec_decode_audio4():
154  * Use avcodec_send_packet() to feed input to the decoder, then use
155  * avcodec_receive_frame() to receive decoded frames after each packet.
156  * Unlike with the old video decoding API, multiple frames might result from
157  * a packet. For audio, splitting the input packet into frames by partially
158  * decoding packets becomes transparent to the API user. You never need to
159  * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
160  * no data was read from the packet).
161  * Additionally, sending a flush/draining packet is required only once.
162  * - avcodec_encode_video2()/avcodec_encode_audio2():
163  * Use avcodec_send_frame() to feed input to the encoder, then use
164  * avcodec_receive_packet() to receive encoded packets.
165  * Providing user-allocated buffers for avcodec_receive_packet() is not
166  * possible.
167  * - The new API does not handle subtitles yet.
168  *
169  * Mixing new and old function calls on the same AVCodecContext is not allowed,
170  * and will result in undefined behavior.
171  *
172  * Some codecs might require using the new API; using the old API will return
173  * an error when calling it. All codecs support the new API.
174  *
175  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
176  * would be an invalid state, which could put the codec user into an endless
177  * loop. The API has no concept of time either: it cannot happen that trying to
178  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
179  * later accepts the packet (with no other receive/flush API calls involved).
180  * The API is a strict state machine, and the passage of time is not supposed
181  * to influence it. Some timing-dependent behavior might still be deemed
182  * acceptable in certain cases. But it must never result in both send/receive
183  * returning EAGAIN at the same time at any point. It must also absolutely be
184  * avoided that the current state is "unstable" and can "flip-flop" between
185  * the send/receive APIs allowing progress. For example, it's not allowed that
186  * the codec randomly decides that it actually wants to consume a packet now
187  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
188  * avcodec_send_packet() call.
189  * @}
190  */
191 
192 /**
193  * @defgroup lavc_core Core functions/structures.
194  * @ingroup libavc
195  *
196  * Basic definitions, functions for querying libavcodec capabilities,
197  * allocating core structures, etc.
198  * @{
199  */
200 
201 
202 /**
203  * Identify the syntax and semantics of the bitstream.
204  * The principle is roughly:
205  * Two decoders with the same ID can decode the same streams.
206  * Two encoders with the same ID can encode compatible streams.
207  * There may be slight deviations from the principle due to implementation
208  * details.
209  *
210  * If you add a codec ID to this list, add it so that
211  * 1. no value of an existing codec ID changes (that would break ABI),
212  * 2. it is as close as possible to similar codecs
213  *
214  * After adding new codec IDs, do not forget to add an entry to the codec
215  * descriptor list and bump libavcodec minor version.
216  */
217 enum AVCodecID {
219 
220  /* video codecs */
222  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
357 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
395 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
415 
466 
467  /* various PCM "codecs" */
468  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
500 
506 
507  /* various ADPCM codecs */
539 
557 
558  /* AMR */
561 
562  /* RealAudio codecs*/
565 
566  /* various DPCM codecs */
571 
575 
576  /* audio codecs */
577  AV_CODEC_ID_MP2 = 0x15000,
578  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
595  AV_CODEC_ID_GSM, ///< as in Berlin toast format
607  AV_CODEC_ID_GSM_MS, /* as found in WAV */
645 
672 
673  /* subtitle codecs */
674  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
677  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
684 
702 
703  /* other specific kind of codecs (generally used for attachments) */
704  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
705  AV_CODEC_ID_TTF = 0x18000,
706 
707  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
717 
718 
719  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
720 
721  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
722  * stream (only used by libavformat) */
723  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
724  * stream (only used by libavformat) */
725  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
726  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
727 };
728 
729 /**
730  * This struct describes the properties of a single codec described by an
731  * AVCodecID.
732  * @see avcodec_descriptor_get()
733  */
734 typedef struct AVCodecDescriptor {
735  enum AVCodecID id;
737  /**
738  * Name of the codec described by this descriptor. It is non-empty and
739  * unique for each codec descriptor. It should contain alphanumeric
740  * characters and '_' only.
741  */
742  const char *name;
743  /**
744  * A more descriptive name for this codec. May be NULL.
745  */
746  const char *long_name;
747  /**
748  * Codec properties, a combination of AV_CODEC_PROP_* flags.
749  */
750  int props;
751  /**
752  * MIME type(s) associated with the codec.
753  * May be NULL; if not, a NULL-terminated array of MIME types.
754  * The first item is always non-NULL and is the preferred MIME type.
755  */
756  const char *const *mime_types;
757  /**
758  * If non-NULL, an array of profiles recognized for this codec.
759  * Terminated with FF_PROFILE_UNKNOWN.
760  */
761  const struct AVProfile *profiles;
763 
764 /**
765  * Codec uses only intra compression.
766  * Video and audio codecs only.
767  */
768 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
769 /**
770  * Codec supports lossy compression. Audio and video codecs only.
771  * @note a codec may support both lossy and lossless
772  * compression modes
773  */
774 #define AV_CODEC_PROP_LOSSY (1 << 1)
775 /**
776  * Codec supports lossless compression. Audio and video codecs only.
777  */
778 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
779 /**
780  * Codec supports frame reordering. That is, the coded order (the order in which
781  * the encoded packets are output by the encoders / stored / input to the
782  * decoders) may be different from the presentation order of the corresponding
783  * frames.
784  *
785  * For codecs that do not have this property set, PTS and DTS should always be
786  * equal.
787  */
788 #define AV_CODEC_PROP_REORDER (1 << 3)
789 /**
790  * Subtitle codec is bitmap based
791  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
792  */
793 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
794 /**
795  * Subtitle codec is text based.
796  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
797  */
798 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
799 
800 /**
801  * @ingroup lavc_decoding
802  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
803  * This is mainly needed because some optimized bitstream readers read
804  * 32 or 64 bit at once and could read over the end.<br>
805  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
806  * MPEG bitstreams could cause overread and segfault.
807  */
808 #define AV_INPUT_BUFFER_PADDING_SIZE 64
809 
810 /**
811  * @ingroup lavc_encoding
812  * minimum encoding buffer size
813  * Used to avoid some checks during header writing.
814  */
815 #define AV_INPUT_BUFFER_MIN_SIZE 16384
816 
817 /**
818  * @ingroup lavc_decoding
819  */
821  /* We leave some space between them for extensions (drop some
822  * keyframes for intra-only or drop just some bidir frames). */
823  AVDISCARD_NONE =-16, ///< discard nothing
824  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
825  AVDISCARD_NONREF = 8, ///< discard all non reference
826  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
827  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
828  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
829  AVDISCARD_ALL = 48, ///< discard all
830 };
831 
842  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
843 };
844 
845 /**
846  * @ingroup lavc_encoding
847  */
848 typedef struct RcOverride{
851  int qscale; // If this is 0 then quality_factor will be used instead.
853 } RcOverride;
854 
855 /* encoding support
856  These flags can be passed in AVCodecContext.flags before initialization.
857  Note: Not everything is supported yet.
858 */
859 
860 /**
861  * Allow decoders to produce frames with data planes that are not aligned
862  * to CPU requirements (e.g. due to cropping).
863  */
864 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
865 /**
866  * Use fixed qscale.
867  */
868 #define AV_CODEC_FLAG_QSCALE (1 << 1)
869 /**
870  * 4 MV per MB allowed / advanced prediction for H.263.
871  */
872 #define AV_CODEC_FLAG_4MV (1 << 2)
873 /**
874  * Output even those frames that might be corrupted.
875  */
876 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
877 /**
878  * Use qpel MC.
879  */
880 #define AV_CODEC_FLAG_QPEL (1 << 4)
881 /**
882  * Don't output frames whose parameters differ from first
883  * decoded frame in stream.
884  */
885 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
886 /**
887  * Use internal 2pass ratecontrol in first pass mode.
888  */
889 #define AV_CODEC_FLAG_PASS1 (1 << 9)
890 /**
891  * Use internal 2pass ratecontrol in second pass mode.
892  */
893 #define AV_CODEC_FLAG_PASS2 (1 << 10)
894 /**
895  * loop filter.
896  */
897 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
898 /**
899  * Only decode/encode grayscale.
900  */
901 #define AV_CODEC_FLAG_GRAY (1 << 13)
902 /**
903  * error[?] variables will be set during encoding.
904  */
905 #define AV_CODEC_FLAG_PSNR (1 << 15)
906 /**
907  * Input bitstream might be truncated at a random location
908  * instead of only at frame boundaries.
909  */
910 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
911 /**
912  * Use interlaced DCT.
913  */
914 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
915 /**
916  * Force low delay.
917  */
918 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
919 /**
920  * Place global headers in extradata instead of every keyframe.
921  */
922 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
923 /**
924  * Use only bitexact stuff (except (I)DCT).
925  */
926 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
927 /* Fx : Flag for H.263+ extra options */
928 /**
929  * H.263 advanced intra coding / MPEG-4 AC prediction
930  */
931 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
932 /**
933  * interlaced motion estimation
934  */
935 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
936 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
937 
938 /**
939  * Allow non spec compliant speedup tricks.
940  */
941 #define AV_CODEC_FLAG2_FAST (1 << 0)
942 /**
943  * Skip bitstream encoding.
944  */
945 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
946 /**
947  * Place global headers at every keyframe instead of in extradata.
948  */
949 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
950 
951 /**
952  * timecode is in drop frame format. DEPRECATED!!!!
953  */
954 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
955 
956 /**
957  * Input bitstream might be truncated at a packet boundaries
958  * instead of only at frame boundaries.
959  */
960 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
961 /**
962  * Discard cropping information from SPS.
963  */
964 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
965 
966 /**
967  * Show all frames before the first keyframe
968  */
969 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
970 /**
971  * Export motion vectors through frame side data
972  */
973 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
974 /**
975  * Do not skip samples and export skip information as frame side data
976  */
977 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
978 /**
979  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
980  */
981 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
982 
983 /* Unsupported options :
984  * Syntax Arithmetic coding (SAC)
985  * Reference Picture Selection
986  * Independent Segment Decoding */
987 /* /Fx */
988 /* codec capabilities */
989 
990 /**
991  * Decoder can use draw_horiz_band callback.
992  */
993 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
994 /**
995  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
996  * If not set, it might not use get_buffer() at all or use operations that
997  * assume the buffer was allocated by avcodec_default_get_buffer.
998  */
999 #define AV_CODEC_CAP_DR1 (1 << 1)
1000 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
1001 /**
1002  * Encoder or decoder requires flushing with NULL input at the end in order to
1003  * give the complete and correct output.
1004  *
1005  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
1006  * with NULL data. The user can still send NULL data to the public encode
1007  * or decode function, but libavcodec will not pass it along to the codec
1008  * unless this flag is set.
1009  *
1010  * Decoders:
1011  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
1012  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
1013  * returns frames.
1014  *
1015  * Encoders:
1016  * The encoder needs to be fed with NULL data at the end of encoding until the
1017  * encoder no longer returns data.
1018  *
1019  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1020  * flag also means that the encoder must set the pts and duration for
1021  * each output packet. If this flag is not set, the pts and duration will
1022  * be determined by libavcodec from the input frame.
1023  */
1024 #define AV_CODEC_CAP_DELAY (1 << 5)
1025 /**
1026  * Codec can be fed a final frame with a smaller size.
1027  * This can be used to prevent truncation of the last audio samples.
1028  */
1029 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
1030 
1031 /**
1032  * Codec can output multiple frames per AVPacket
1033  * Normally demuxers return one frame at a time, demuxers which do not do
1034  * are connected to a parser to split what they return into proper frames.
1035  * This flag is reserved to the very rare category of codecs which have a
1036  * bitstream that cannot be split into frames without timeconsuming
1037  * operations like full decoding. Demuxers carrying such bitstreams thus
1038  * may return multiple frames in a packet. This has many disadvantages like
1039  * prohibiting stream copy in many cases thus it should only be considered
1040  * as a last resort.
1041  */
1042 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1043 /**
1044  * Codec is experimental and is thus avoided in favor of non experimental
1045  * encoders
1046  */
1047 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1048 /**
1049  * Codec should fill in channel configuration and samplerate instead of container
1050  */
1051 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1052 /**
1053  * Codec supports frame-level multithreading.
1054  */
1055 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1056 /**
1057  * Codec supports slice-based (or partition-based) multithreading.
1058  */
1059 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1060 /**
1061  * Codec supports changed parameters at any point.
1062  */
1063 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1064 /**
1065  * Codec supports avctx->thread_count == 0 (auto).
1066  */
1067 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1068 /**
1069  * Audio encoder supports receiving a different number of samples in each call.
1070  */
1071 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1072 /**
1073  * Decoder is not a preferred choice for probing.
1074  * This indicates that the decoder is not a good choice for probing.
1075  * It could for example be an expensive to spin up hardware decoder,
1076  * or it could simply not provide a lot of useful information about
1077  * the stream.
1078  * A decoder marked with this flag should only be used as last resort
1079  * choice for probing.
1080  */
1081 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1082 /**
1083  * Codec is intra only.
1084  */
1085 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1086 /**
1087  * Codec is lossless.
1088  */
1089 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1090 
1091 /**
1092  * Codec is backed by a hardware implementation. Typically used to
1093  * identify a non-hwaccel hardware decoder. For information about hwaccels, use
1094  * avcodec_get_hw_config() instead.
1095  */
1096 #define AV_CODEC_CAP_HARDWARE (1 << 18)
1097 
1098 /**
1099  * Codec is potentially backed by a hardware implementation, but not
1100  * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
1101  * implementation provides some sort of internal fallback.
1102  */
1103 #define AV_CODEC_CAP_HYBRID (1 << 19)
1104 
1105 /**
1106  * This codec takes the reordered_opaque field from input AVFrames
1107  * and returns it in the corresponding field in AVCodecContext after
1108  * encoding.
1109  */
1110 #define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
1111 
1112 /* Exported side data.
1113  These flags can be passed in AVCodecContext.export_side_data before initialization.
1114 */
1115 /**
1116  * Export motion vectors through frame side data
1117  */
1118 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
1119 /**
1120  * Export encoder Producer Reference Time through packet side data
1121  */
1122 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
1123 
1124 /**
1125  * Pan Scan area.
1126  * This specifies the area which should be displayed.
1127  * Note there may be multiple such areas for one frame.
1128  */
1129 typedef struct AVPanScan {
1130  /**
1131  * id
1132  * - encoding: Set by user.
1133  * - decoding: Set by libavcodec.
1134  */
1135  int id;
1136 
1137  /**
1138  * width and height in 1/16 pel
1139  * - encoding: Set by user.
1140  * - decoding: Set by libavcodec.
1141  */
1142  int width;
1143  int height;
1144 
1145  /**
1146  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1147  * - encoding: Set by user.
1148  * - decoding: Set by libavcodec.
1149  */
1150  int16_t position[3][2];
1151 } AVPanScan;
1152 
1153 /**
1154  * This structure describes the bitrate properties of an encoded bitstream. It
1155  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1156  * parameters for H.264/HEVC.
1157  */
1158 typedef struct AVCPBProperties {
1159  /**
1160  * Maximum bitrate of the stream, in bits per second.
1161  * Zero if unknown or unspecified.
1162  */
1163 #if FF_API_UNSANITIZED_BITRATES
1165 #else
1166  int64_t max_bitrate;
1167 #endif
1168  /**
1169  * Minimum bitrate of the stream, in bits per second.
1170  * Zero if unknown or unspecified.
1171  */
1172 #if FF_API_UNSANITIZED_BITRATES
1174 #else
1175  int64_t min_bitrate;
1176 #endif
1177  /**
1178  * Average bitrate of the stream, in bits per second.
1179  * Zero if unknown or unspecified.
1180  */
1181 #if FF_API_UNSANITIZED_BITRATES
1183 #else
1184  int64_t avg_bitrate;
1185 #endif
1186 
1187  /**
1188  * The size of the buffer to which the ratecontrol is applied, in bits.
1189  * Zero if unknown or unspecified.
1190  */
1192 
1193  /**
1194  * The delay between the time the packet this structure is associated with
1195  * is received and the time when it should be decoded, in periods of a 27MHz
1196  * clock.
1197  *
1198  * UINT64_MAX when unknown or unspecified.
1199  */
1200  uint64_t vbv_delay;
1201 } AVCPBProperties;
1202 
1203 /**
1204  * This structure supplies correlation between a packet timestamp and a wall clock
1205  * production time. The definition follows the Producer Reference Time ('prft')
1206  * as defined in ISO/IEC 14496-12
1207  */
1208 typedef struct AVProducerReferenceTime {
1209  /**
1210  * A UTC timestamp, in microseconds, since Unix epoch (e.g, av_gettime()).
1211  */
1212  int64_t wallclock;
1213  int flags;
1215 
1216 /**
1217  * The decoder will keep a reference to the frame and may reuse it later.
1218  */
1219 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1220 
1221 /**
1222  * @defgroup lavc_packet AVPacket
1223  *
1224  * Types and functions for working with AVPacket.
1225  * @{
1226  */
1228  /**
1229  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1230  * bytes worth of palette. This side data signals that a new palette is
1231  * present.
1232  */
1234 
1235  /**
1236  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1237  * that the extradata buffer was changed and the receiving side should
1238  * act upon it appropriately. The new extradata is embedded in the side
1239  * data buffer and should be immediately used for processing the current
1240  * frame or packet.
1241  */
1243 
1244  /**
1245  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1246  * @code
1247  * u32le param_flags
1248  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1249  * s32le channel_count
1250  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1251  * u64le channel_layout
1252  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1253  * s32le sample_rate
1254  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1255  * s32le width
1256  * s32le height
1257  * @endcode
1258  */
1260 
1261  /**
1262  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1263  * structures with info about macroblocks relevant to splitting the
1264  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1265  * That is, it does not necessarily contain info about all macroblocks,
1266  * as long as the distance between macroblocks in the info is smaller
1267  * than the target payload size.
1268  * Each MB info structure is 12 bytes, and is laid out as follows:
1269  * @code
1270  * u32le bit offset from the start of the packet
1271  * u8 current quantizer at the start of the macroblock
1272  * u8 GOB number
1273  * u16le macroblock address within the GOB
1274  * u8 horizontal MV predictor
1275  * u8 vertical MV predictor
1276  * u8 horizontal MV predictor for block number 3
1277  * u8 vertical MV predictor for block number 3
1278  * @endcode
1279  */
1281 
1282  /**
1283  * This side data should be associated with an audio stream and contains
1284  * ReplayGain information in form of the AVReplayGain struct.
1285  */
1287 
1288  /**
1289  * This side data contains a 3x3 transformation matrix describing an affine
1290  * transformation that needs to be applied to the decoded video frames for
1291  * correct presentation.
1292  *
1293  * See libavutil/display.h for a detailed description of the data.
1294  */
1296 
1297  /**
1298  * This side data should be associated with a video stream and contains
1299  * Stereoscopic 3D information in form of the AVStereo3D struct.
1300  */
1302 
1303  /**
1304  * This side data should be associated with an audio stream and corresponds
1305  * to enum AVAudioServiceType.
1306  */
1308 
1309  /**
1310  * This side data contains quality related information from the encoder.
1311  * @code
1312  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1313  * u8 picture type
1314  * u8 error count
1315  * u16 reserved
1316  * u64le[error count] sum of squared differences between encoder in and output
1317  * @endcode
1318  */
1320 
1321  /**
1322  * This side data contains an integer value representing the stream index
1323  * of a "fallback" track. A fallback track indicates an alternate
1324  * track to use when the current track can not be decoded for some reason.
1325  * e.g. no decoder available for codec.
1326  */
1328 
1329  /**
1330  * This side data corresponds to the AVCPBProperties struct.
1331  */
1333 
1334  /**
1335  * Recommmends skipping the specified number of samples
1336  * @code
1337  * u32le number of samples to skip from start of this packet
1338  * u32le number of samples to skip from end of this packet
1339  * u8 reason for start skip
1340  * u8 reason for end skip (0=padding silence, 1=convergence)
1341  * @endcode
1342  */
1344 
1345  /**
1346  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1347  * the packet may contain "dual mono" audio specific to Japanese DTV
1348  * and if it is true, recommends only the selected channel to be used.
1349  * @code
1350  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1351  * @endcode
1352  */
1354 
1355  /**
1356  * A list of zero terminated key/value strings. There is no end marker for
1357  * the list, so it is required to rely on the side data size to stop.
1358  */
1360 
1361  /**
1362  * Subtitle event position
1363  * @code
1364  * u32le x1
1365  * u32le y1
1366  * u32le x2
1367  * u32le y2
1368  * @endcode
1369  */
1371 
1372  /**
1373  * Data found in BlockAdditional element of matroska container. There is
1374  * no end marker for the data, so it is required to rely on the side data
1375  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1376  * by data.
1377  */
1379 
1380  /**
1381  * The optional first identifier line of a WebVTT cue.
1382  */
1384 
1385  /**
1386  * The optional settings (rendering instructions) that immediately
1387  * follow the timestamp specifier of a WebVTT cue.
1388  */
1390 
1391  /**
1392  * A list of zero terminated key/value strings. There is no end marker for
1393  * the list, so it is required to rely on the side data size to stop. This
1394  * side data includes updated metadata which appeared in the stream.
1395  */
1397 
1398  /**
1399  * MPEGTS stream ID as uint8_t, this is required to pass the stream ID
1400  * information from the demuxer to the corresponding muxer.
1401  */
1403 
1404  /**
1405  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1406  * should be associated with a video stream and contains data in the form
1407  * of the AVMasteringDisplayMetadata struct.
1408  */
1410 
1411  /**
1412  * This side data should be associated with a video stream and corresponds
1413  * to the AVSphericalMapping structure.
1414  */
1416 
1417  /**
1418  * Content light level (based on CTA-861.3). This metadata should be
1419  * associated with a video stream and contains data in the form of the
1420  * AVContentLightMetadata struct.
1421  */
1423 
1424  /**
1425  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1426  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1427  * The number of bytes of CC data is AVPacketSideData.size.
1428  */
1430 
1431  /**
1432  * This side data is encryption initialization data.
1433  * The format is not part of ABI, use av_encryption_init_info_* methods to
1434  * access.
1435  */
1437 
1438  /**
1439  * This side data contains encryption info for how to decrypt the packet.
1440  * The format is not part of ABI, use av_encryption_info_* methods to access.
1441  */
1443 
1444  /**
1445  * Active Format Description data consisting of a single byte as specified
1446  * in ETSI TS 101 154 using AVActiveFormatDescription enum.
1447  */
1449 
1450  /**
1451  * Producer Reference Time data corresponding to the AVProducerReferenceTime struct,
1452  * usually exported by some encoders (on demand through the prft flag set in the
1453  * AVCodecContext export_side_data field).
1454  */
1456 
1457  /**
1458  * ICC profile data consisting of an opaque octet buffer following the
1459  * format described by ISO 15076-1.
1460  */
1462 
1463  /**
1464  * The number of side data types.
1465  * This is not part of the public API/ABI in the sense that it may
1466  * change when new side data types are added.
1467  * This must stay the last enum value.
1468  * If its value becomes huge, some code using it
1469  * needs to be updated as it assumes it to be smaller than other limits.
1470  */
1472 };
1473 
1474 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1475 
1476 typedef struct AVPacketSideData {
1478  int size;
1481 
1482 /**
1483  * This structure stores compressed data. It is typically exported by demuxers
1484  * and then passed as input to decoders, or received as output from encoders and
1485  * then passed to muxers.
1486  *
1487  * For video, it should typically contain one compressed frame. For audio it may
1488  * contain several compressed frames. Encoders are allowed to output empty
1489  * packets, with no compressed data, containing only side data
1490  * (e.g. to update some stream parameters at the end of encoding).
1491  *
1492  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1493  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1494  * without libavcodec and libavformat major bump.
1495  *
1496  * The semantics of data ownership depends on the buf field.
1497  * If it is set, the packet data is dynamically allocated and is
1498  * valid indefinitely until a call to av_packet_unref() reduces the
1499  * reference count to 0.
1500  *
1501  * If the buf field is not set av_packet_ref() would make a copy instead
1502  * of increasing the reference count.
1503  *
1504  * The side data is always allocated with av_malloc(), copied by
1505  * av_packet_ref() and freed by av_packet_unref().
1506  *
1507  * @see av_packet_ref
1508  * @see av_packet_unref
1509  */
1510 typedef struct AVPacket {
1511  /**
1512  * A reference to the reference-counted buffer where the packet data is
1513  * stored.
1514  * May be NULL, then the packet data is not reference-counted.
1515  */
1517  /**
1518  * Presentation timestamp in AVStream->time_base units; the time at which
1519  * the decompressed packet will be presented to the user.
1520  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1521  * pts MUST be larger or equal to dts as presentation cannot happen before
1522  * decompression, unless one wants to view hex dumps. Some formats misuse
1523  * the terms dts and pts/cts to mean something different. Such timestamps
1524  * must be converted to true pts/dts before they are stored in AVPacket.
1525  */
1526  int64_t pts;
1527  /**
1528  * Decompression timestamp in AVStream->time_base units; the time at which
1529  * the packet is decompressed.
1530  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1531  */
1532  int64_t dts;
1534  int size;
1536  /**
1537  * A combination of AV_PKT_FLAG values
1538  */
1539  int flags;
1540  /**
1541  * Additional packet data that can be provided by the container.
1542  * Packet can contain several types of side information.
1543  */
1546 
1547  /**
1548  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1549  * Equals next_pts - this_pts in presentation order.
1550  */
1551  int64_t duration;
1552 
1553  int64_t pos; ///< byte position in stream, -1 if unknown
1554 
1555 #if FF_API_CONVERGENCE_DURATION
1556  /**
1557  * @deprecated Same as the duration field, but as int64_t. This was required
1558  * for Matroska subtitles, whose duration values could overflow when the
1559  * duration field was still an int.
1560  */
1563 #endif
1564 } AVPacket;
1565 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1566 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1567 /**
1568  * Flag is used to discard packets which are required to maintain valid
1569  * decoder state but are not required for output and should be dropped
1570  * after decoding.
1571  **/
1572 #define AV_PKT_FLAG_DISCARD 0x0004
1573 /**
1574  * The packet comes from a trusted source.
1575  *
1576  * Otherwise-unsafe constructs such as arbitrary pointers to data
1577  * outside the packet may be followed.
1578  */
1579 #define AV_PKT_FLAG_TRUSTED 0x0008
1580 /**
1581  * Flag is used to indicate packets that contain frames that can
1582  * be discarded by the decoder. I.e. Non-reference frames.
1583  */
1584 #define AV_PKT_FLAG_DISPOSABLE 0x0010
1585 
1586 
1592 };
1593 /**
1594  * @}
1595  */
1596 
1597 struct AVCodecInternal;
1598 
1602  AV_FIELD_TT, //< Top coded_first, top displayed first
1603  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1604  AV_FIELD_TB, //< Top coded first, bottom displayed first
1605  AV_FIELD_BT, //< Bottom coded first, top displayed first
1606 };
1607 
1608 /**
1609  * main external API structure.
1610  * New fields can be added to the end with minor version bumps.
1611  * Removal, reordering and changes to existing fields require a major
1612  * version bump.
1613  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1614  * applications.
1615  * The name string for AVOptions options matches the associated command line
1616  * parameter name and can be found in libavcodec/options_table.h
1617  * The AVOption/command line parameter names differ in some cases from the C
1618  * structure field names for historic reasons or brevity.
1619  * sizeof(AVCodecContext) must not be used outside libav*.
1620  */
1621 typedef struct AVCodecContext {
1622  /**
1623  * information on struct for av_log
1624  * - set by avcodec_alloc_context3
1625  */
1628 
1629  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1630  const struct AVCodec *codec;
1631  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1632 
1633  /**
1634  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1635  * This is used to work around some encoder bugs.
1636  * A demuxer should set this to what is stored in the field used to identify the codec.
1637  * If there are multiple such fields in a container then the demuxer should choose the one
1638  * which maximizes the information about the used codec.
1639  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1640  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1641  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1642  * first.
1643  * - encoding: Set by user, if not then the default based on codec_id will be used.
1644  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1645  */
1646  unsigned int codec_tag;
1647 
1648  void *priv_data;
1649 
1650  /**
1651  * Private context used for internal data.
1652  *
1653  * Unlike priv_data, this is not codec-specific. It is used in general
1654  * libavcodec functions.
1655  */
1656  struct AVCodecInternal *internal;
1657 
1658  /**
1659  * Private data of the user, can be used to carry app specific stuff.
1660  * - encoding: Set by user.
1661  * - decoding: Set by user.
1662  */
1663  void *opaque;
1664 
1665  /**
1666  * the average bitrate
1667  * - encoding: Set by user; unused for constant quantizer encoding.
1668  * - decoding: Set by user, may be overwritten by libavcodec
1669  * if this info is available in the stream
1670  */
1671  int64_t bit_rate;
1672 
1673  /**
1674  * number of bits the bitstream is allowed to diverge from the reference.
1675  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1676  * - encoding: Set by user; unused for constant quantizer encoding.
1677  * - decoding: unused
1678  */
1680 
1681  /**
1682  * Global quality for codecs which cannot change it per frame.
1683  * This should be proportional to MPEG-1/2/4 qscale.
1684  * - encoding: Set by user.
1685  * - decoding: unused
1686  */
1688 
1689  /**
1690  * - encoding: Set by user.
1691  * - decoding: unused
1692  */
1694 #define FF_COMPRESSION_DEFAULT -1
1695 
1696  /**
1697  * AV_CODEC_FLAG_*.
1698  * - encoding: Set by user.
1699  * - decoding: Set by user.
1700  */
1701  int flags;
1702 
1703  /**
1704  * AV_CODEC_FLAG2_*
1705  * - encoding: Set by user.
1706  * - decoding: Set by user.
1707  */
1708  int flags2;
1709 
1710  /**
1711  * some codecs need / can use extradata like Huffman tables.
1712  * MJPEG: Huffman tables
1713  * rv10: additional flags
1714  * MPEG-4: global headers (they can be in the bitstream or here)
1715  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1716  * than extradata_size to avoid problems if it is read with the bitstream reader.
1717  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1718  * Must be allocated with the av_malloc() family of functions.
1719  * - encoding: Set/allocated/freed by libavcodec.
1720  * - decoding: Set/allocated/freed by user.
1721  */
1724 
1725  /**
1726  * This is the fundamental unit of time (in seconds) in terms
1727  * of which frame timestamps are represented. For fixed-fps content,
1728  * timebase should be 1/framerate and timestamp increments should be
1729  * identically 1.
1730  * This often, but not always is the inverse of the frame rate or field rate
1731  * for video. 1/time_base is not the average frame rate if the frame rate is not
1732  * constant.
1733  *
1734  * Like containers, elementary streams also can store timestamps, 1/time_base
1735  * is the unit in which these timestamps are specified.
1736  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1737  * vop_time_increment_resolution and fixed_vop_rate
1738  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1739  *
1740  * - encoding: MUST be set by user.
1741  * - decoding: the use of this field for decoding is deprecated.
1742  * Use framerate instead.
1743  */
1745 
1746  /**
1747  * For some codecs, the time base is closer to the field rate than the frame rate.
1748  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1749  * if no telecine is used ...
1750  *
1751  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1752  */
1754 
1755  /**
1756  * Codec delay.
1757  *
1758  * Encoding: Number of frames delay there will be from the encoder input to
1759  * the decoder output. (we assume the decoder matches the spec)
1760  * Decoding: Number of frames delay in addition to what a standard decoder
1761  * as specified in the spec would produce.
1762  *
1763  * Video:
1764  * Number of frames the decoded output will be delayed relative to the
1765  * encoded input.
1766  *
1767  * Audio:
1768  * For encoding, this field is unused (see initial_padding).
1769  *
1770  * For decoding, this is the number of samples the decoder needs to
1771  * output before the decoder's output is valid. When seeking, you should
1772  * start decoding this many samples prior to your desired seek point.
1773  *
1774  * - encoding: Set by libavcodec.
1775  * - decoding: Set by libavcodec.
1776  */
1777  int delay;
1778 
1779 
1780  /* video only */
1781  /**
1782  * picture width / height.
1783  *
1784  * @note Those fields may not match the values of the last
1785  * AVFrame output by avcodec_decode_video2 due frame
1786  * reordering.
1787  *
1788  * - encoding: MUST be set by user.
1789  * - decoding: May be set by the user before opening the decoder if known e.g.
1790  * from the container. Some decoders will require the dimensions
1791  * to be set by the caller. During decoding, the decoder may
1792  * overwrite those values as required while parsing the data.
1793  */
1795 
1796  /**
1797  * Bitstream width / height, may be different from width/height e.g. when
1798  * the decoded frame is cropped before being output or lowres is enabled.
1799  *
1800  * @note Those field may not match the value of the last
1801  * AVFrame output by avcodec_receive_frame() due frame
1802  * reordering.
1803  *
1804  * - encoding: unused
1805  * - decoding: May be set by the user before opening the decoder if known
1806  * e.g. from the container. During decoding, the decoder may
1807  * overwrite those values as required while parsing the data.
1808  */
1809  int coded_width, coded_height;
1810 
1811  /**
1812  * the number of pictures in a group of pictures, or 0 for intra_only
1813  * - encoding: Set by user.
1814  * - decoding: unused
1815  */
1817 
1818  /**
1819  * Pixel format, see AV_PIX_FMT_xxx.
1820  * May be set by the demuxer if known from headers.
1821  * May be overridden by the decoder if it knows better.
1822  *
1823  * @note This field may not match the value of the last
1824  * AVFrame output by avcodec_receive_frame() due frame
1825  * reordering.
1826  *
1827  * - encoding: Set by user.
1828  * - decoding: Set by user if known, overridden by libavcodec while
1829  * parsing the data.
1830  */
1832 
1833  /**
1834  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1835  * decoder to draw a horizontal band. It improves cache usage. Not
1836  * all codecs can do that. You must check the codec capabilities
1837  * beforehand.
1838  * When multithreading is used, it may be called from multiple threads
1839  * at the same time; threads might draw different parts of the same AVFrame,
1840  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1841  * in order.
1842  * The function is also used by hardware acceleration APIs.
1843  * It is called at least once during frame decoding to pass
1844  * the data needed for hardware render.
1845  * In that mode instead of pixel data, AVFrame points to
1846  * a structure specific to the acceleration API. The application
1847  * reads the structure and can change some fields to indicate progress
1848  * or mark state.
1849  * - encoding: unused
1850  * - decoding: Set by user.
1851  * @param height the height of the slice
1852  * @param y the y position of the slice
1853  * @param type 1->top field, 2->bottom field, 3->frame
1854  * @param offset offset into the AVFrame.data from which the slice should be read
1855  */
1857  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1858  int y, int type, int height);
1859 
1860  /**
1861  * callback to negotiate the pixelFormat
1862  * @param fmt is the list of formats which are supported by the codec,
1863  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1864  * The first is always the native one.
1865  * @note The callback may be called again immediately if initialization for
1866  * the selected (hardware-accelerated) pixel format failed.
1867  * @warning Behavior is undefined if the callback returns a value not
1868  * in the fmt list of formats.
1869  * @return the chosen format
1870  * - encoding: unused
1871  * - decoding: Set by user, if not set the native format will be chosen.
1872  */
1873  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1874 
1875  /**
1876  * maximum number of B-frames between non-B-frames
1877  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1878  * - encoding: Set by user.
1879  * - decoding: unused
1880  */
1882 
1883  /**
1884  * qscale factor between IP and B-frames
1885  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1886  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1887  * - encoding: Set by user.
1888  * - decoding: unused
1889  */
1891 
1892 #if FF_API_PRIVATE_OPT
1893  /** @deprecated use encoder private options instead */
1896 #endif
1897 
1898  /**
1899  * qscale offset between IP and B-frames
1900  * - encoding: Set by user.
1901  * - decoding: unused
1902  */
1904 
1905  /**
1906  * Size of the frame reordering buffer in the decoder.
1907  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1908  * - encoding: Set by libavcodec.
1909  * - decoding: Set by libavcodec.
1910  */
1912 
1913 #if FF_API_PRIVATE_OPT
1914  /** @deprecated use encoder private options instead */
1917 #endif
1918 
1919  /**
1920  * qscale factor between P- and I-frames
1921  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1922  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1923  * - encoding: Set by user.
1924  * - decoding: unused
1925  */
1927 
1928  /**
1929  * qscale offset between P and I-frames
1930  * - encoding: Set by user.
1931  * - decoding: unused
1932  */
1934 
1935  /**
1936  * luminance masking (0-> disabled)
1937  * - encoding: Set by user.
1938  * - decoding: unused
1939  */
1941 
1942  /**
1943  * temporary complexity masking (0-> disabled)
1944  * - encoding: Set by user.
1945  * - decoding: unused
1946  */
1948 
1949  /**
1950  * spatial complexity masking (0-> disabled)
1951  * - encoding: Set by user.
1952  * - decoding: unused
1953  */
1955 
1956  /**
1957  * p block masking (0-> disabled)
1958  * - encoding: Set by user.
1959  * - decoding: unused
1960  */
1961  float p_masking;
1962 
1963  /**
1964  * darkness masking (0-> disabled)
1965  * - encoding: Set by user.
1966  * - decoding: unused
1967  */
1969 
1970  /**
1971  * slice count
1972  * - encoding: Set by libavcodec.
1973  * - decoding: Set by user (or 0).
1974  */
1976 
1977 #if FF_API_PRIVATE_OPT
1978  /** @deprecated use encoder private options instead */
1981 #define FF_PRED_LEFT 0
1982 #define FF_PRED_PLANE 1
1983 #define FF_PRED_MEDIAN 2
1984 #endif
1985 
1986  /**
1987  * slice offsets in the frame in bytes
1988  * - encoding: Set/allocated by libavcodec.
1989  * - decoding: Set/allocated by user (or NULL).
1990  */
1992 
1993  /**
1994  * sample aspect ratio (0 if unknown)
1995  * That is the width of a pixel divided by the height of the pixel.
1996  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1997  * - encoding: Set by user.
1998  * - decoding: Set by libavcodec.
1999  */
2001 
2002  /**
2003  * motion estimation comparison function
2004  * - encoding: Set by user.
2005  * - decoding: unused
2006  */
2007  int me_cmp;
2008  /**
2009  * subpixel motion estimation comparison function
2010  * - encoding: Set by user.
2011  * - decoding: unused
2012  */
2014  /**
2015  * macroblock comparison function (not supported yet)
2016  * - encoding: Set by user.
2017  * - decoding: unused
2018  */
2019  int mb_cmp;
2020  /**
2021  * interlaced DCT comparison function
2022  * - encoding: Set by user.
2023  * - decoding: unused
2024  */
2026 #define FF_CMP_SAD 0
2027 #define FF_CMP_SSE 1
2028 #define FF_CMP_SATD 2
2029 #define FF_CMP_DCT 3
2030 #define FF_CMP_PSNR 4
2031 #define FF_CMP_BIT 5
2032 #define FF_CMP_RD 6
2033 #define FF_CMP_ZERO 7
2034 #define FF_CMP_VSAD 8
2035 #define FF_CMP_VSSE 9
2036 #define FF_CMP_NSSE 10
2037 #define FF_CMP_W53 11
2038 #define FF_CMP_W97 12
2039 #define FF_CMP_DCTMAX 13
2040 #define FF_CMP_DCT264 14
2041 #define FF_CMP_MEDIAN_SAD 15
2042 #define FF_CMP_CHROMA 256
2043 
2044  /**
2045  * ME diamond size & shape
2046  * - encoding: Set by user.
2047  * - decoding: unused
2048  */
2050 
2051  /**
2052  * amount of previous MV predictors (2a+1 x 2a+1 square)
2053  * - encoding: Set by user.
2054  * - decoding: unused
2055  */
2057 
2058 #if FF_API_PRIVATE_OPT
2059  /** @deprecated use encoder private options instead */
2061  int pre_me;
2062 #endif
2063 
2064  /**
2065  * motion estimation prepass comparison function
2066  * - encoding: Set by user.
2067  * - decoding: unused
2068  */
2070 
2071  /**
2072  * ME prepass diamond size & shape
2073  * - encoding: Set by user.
2074  * - decoding: unused
2075  */
2077 
2078  /**
2079  * subpel ME quality
2080  * - encoding: Set by user.
2081  * - decoding: unused
2082  */
2084 
2085  /**
2086  * maximum motion estimation search range in subpel units
2087  * If 0 then no limit.
2088  *
2089  * - encoding: Set by user.
2090  * - decoding: unused
2091  */
2093 
2094  /**
2095  * slice flags
2096  * - encoding: unused
2097  * - decoding: Set by user.
2098  */
2100 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2101 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2102 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2103 
2104  /**
2105  * macroblock decision mode
2106  * - encoding: Set by user.
2107  * - decoding: unused
2108  */
2110 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2111 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2112 #define FF_MB_DECISION_RD 2 ///< rate distortion
2113 
2114  /**
2115  * custom intra quantization matrix
2116  * Must be allocated with the av_malloc() family of functions, and will be freed in
2117  * avcodec_free_context().
2118  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
2119  * - decoding: Set/allocated/freed by libavcodec.
2120  */
2121  uint16_t *intra_matrix;
2122 
2123  /**
2124  * custom inter quantization matrix
2125  * Must be allocated with the av_malloc() family of functions, and will be freed in
2126  * avcodec_free_context().
2127  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
2128  * - decoding: Set/allocated/freed by libavcodec.
2129  */
2130  uint16_t *inter_matrix;
2131 
2132 #if FF_API_PRIVATE_OPT
2133  /** @deprecated use encoder private options instead */
2136 
2137  /** @deprecated use encoder private options instead */
2140 #endif
2141 
2142  /**
2143  * precision of the intra DC coefficient - 8
2144  * - encoding: Set by user.
2145  * - decoding: Set by libavcodec
2146  */
2148 
2149  /**
2150  * Number of macroblock rows at the top which are skipped.
2151  * - encoding: unused
2152  * - decoding: Set by user.
2153  */
2155 
2156  /**
2157  * Number of macroblock rows at the bottom which are skipped.
2158  * - encoding: unused
2159  * - decoding: Set by user.
2160  */
2162 
2163  /**
2164  * minimum MB Lagrange multiplier
2165  * - encoding: Set by user.
2166  * - decoding: unused
2167  */
2168  int mb_lmin;
2169 
2170  /**
2171  * maximum MB Lagrange multiplier
2172  * - encoding: Set by user.
2173  * - decoding: unused
2174  */
2175  int mb_lmax;
2176 
2177 #if FF_API_PRIVATE_OPT
2178  /**
2179  * @deprecated use encoder private options instead
2180  */
2183 #endif
2184 
2185  /**
2186  * - encoding: Set by user.
2187  * - decoding: unused
2188  */
2190 
2191 #if FF_API_PRIVATE_OPT
2192  /** @deprecated use encoder private options instead */
2195 #endif
2196 
2197  /**
2198  * minimum GOP size
2199  * - encoding: Set by user.
2200  * - decoding: unused
2201  */
2203 
2204  /**
2205  * number of reference frames
2206  * - encoding: Set by user.
2207  * - decoding: Set by lavc.
2208  */
2209  int refs;
2210 
2211 #if FF_API_PRIVATE_OPT
2212  /** @deprecated use encoder private options instead */
2215 #endif
2216 
2217  /**
2218  * Note: Value depends upon the compare function used for fullpel ME.
2219  * - encoding: Set by user.
2220  * - decoding: unused
2221  */
2223 
2224 #if FF_API_PRIVATE_OPT
2225  /** @deprecated use encoder private options instead */
2228 #endif
2229 
2230  /**
2231  * Chromaticity coordinates of the source primaries.
2232  * - encoding: Set by user
2233  * - decoding: Set by libavcodec
2234  */
2236 
2237  /**
2238  * Color Transfer Characteristic.
2239  * - encoding: Set by user
2240  * - decoding: Set by libavcodec
2241  */
2243 
2244  /**
2245  * YUV colorspace type.
2246  * - encoding: Set by user
2247  * - decoding: Set by libavcodec
2248  */
2250 
2251  /**
2252  * MPEG vs JPEG YUV range.
2253  * - encoding: Set by user
2254  * - decoding: Set by libavcodec
2255  */
2257 
2258  /**
2259  * This defines the location of chroma samples.
2260  * - encoding: Set by user
2261  * - decoding: Set by libavcodec
2262  */
2264 
2265  /**
2266  * Number of slices.
2267  * Indicates number of picture subdivisions. Used for parallelized
2268  * decoding.
2269  * - encoding: Set by user
2270  * - decoding: unused
2271  */
2272  int slices;
2273 
2274  /** Field order
2275  * - encoding: set by libavcodec
2276  * - decoding: Set by user.
2277  */
2279 
2280  /* audio only */
2281  int sample_rate; ///< samples per second
2282  int channels; ///< number of audio channels
2283 
2284  /**
2285  * audio sample format
2286  * - encoding: Set by user.
2287  * - decoding: Set by libavcodec.
2288  */
2289  enum AVSampleFormat sample_fmt; ///< sample format
2290 
2291  /* The following data should not be initialized. */
2292  /**
2293  * Number of samples per channel in an audio frame.
2294  *
2295  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2296  * except the last must contain exactly frame_size samples per channel.
2297  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2298  * frame size is not restricted.
2299  * - decoding: may be set by some decoders to indicate constant frame size
2300  */
2302 
2303  /**
2304  * Frame counter, set by libavcodec.
2305  *
2306  * - decoding: total number of frames returned from the decoder so far.
2307  * - encoding: total number of frames passed to the encoder so far.
2308  *
2309  * @note the counter is not incremented if encoding/decoding resulted in
2310  * an error.
2311  */
2313 
2314  /**
2315  * number of bytes per packet if constant and known or 0
2316  * Used by some WAV based audio codecs.
2317  */
2319 
2320  /**
2321  * Audio cutoff bandwidth (0 means "automatic")
2322  * - encoding: Set by user.
2323  * - decoding: unused
2324  */
2325  int cutoff;
2326 
2327  /**
2328  * Audio channel layout.
2329  * - encoding: set by user.
2330  * - decoding: set by user, may be overwritten by libavcodec.
2331  */
2332  uint64_t channel_layout;
2333 
2334  /**
2335  * Request decoder to use this channel layout if it can (0 for default)
2336  * - encoding: unused
2337  * - decoding: Set by user.
2338  */
2340 
2341  /**
2342  * Type of service that the audio stream conveys.
2343  * - encoding: Set by user.
2344  * - decoding: Set by libavcodec.
2345  */
2347 
2348  /**
2349  * desired sample format
2350  * - encoding: Not used.
2351  * - decoding: Set by user.
2352  * Decoder will decode to this format if it can.
2353  */
2355 
2356  /**
2357  * This callback is called at the beginning of each frame to get data
2358  * buffer(s) for it. There may be one contiguous buffer for all the data or
2359  * there may be a buffer per each data plane or anything in between. What
2360  * this means is, you may set however many entries in buf[] you feel necessary.
2361  * Each buffer must be reference-counted using the AVBuffer API (see description
2362  * of buf[] below).
2363  *
2364  * The following fields will be set in the frame before this callback is
2365  * called:
2366  * - format
2367  * - width, height (video only)
2368  * - sample_rate, channel_layout, nb_samples (audio only)
2369  * Their values may differ from the corresponding values in
2370  * AVCodecContext. This callback must use the frame values, not the codec
2371  * context values, to calculate the required buffer size.
2372  *
2373  * This callback must fill the following fields in the frame:
2374  * - data[]
2375  * - linesize[]
2376  * - extended_data:
2377  * * if the data is planar audio with more than 8 channels, then this
2378  * callback must allocate and fill extended_data to contain all pointers
2379  * to all data planes. data[] must hold as many pointers as it can.
2380  * extended_data must be allocated with av_malloc() and will be freed in
2381  * av_frame_unref().
2382  * * otherwise extended_data must point to data
2383  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2384  * the frame's data and extended_data pointers must be contained in these. That
2385  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2386  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2387  * and av_buffer_ref().
2388  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2389  * this callback and filled with the extra buffers if there are more
2390  * buffers than buf[] can hold. extended_buf will be freed in
2391  * av_frame_unref().
2392  *
2393  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2394  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2395  * some other means.
2396  *
2397  * Each data plane must be aligned to the maximum required by the target
2398  * CPU.
2399  *
2400  * @see avcodec_default_get_buffer2()
2401  *
2402  * Video:
2403  *
2404  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2405  * (read and/or written to if it is writable) later by libavcodec.
2406  *
2407  * avcodec_align_dimensions2() should be used to find the required width and
2408  * height, as they normally need to be rounded up to the next multiple of 16.
2409  *
2410  * Some decoders do not support linesizes changing between frames.
2411  *
2412  * If frame multithreading is used and thread_safe_callbacks is set,
2413  * this callback may be called from a different thread, but not from more
2414  * than one at once. Does not need to be reentrant.
2415  *
2416  * @see avcodec_align_dimensions2()
2417  *
2418  * Audio:
2419  *
2420  * Decoders request a buffer of a particular size by setting
2421  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2422  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2423  * to a smaller value in the output frame.
2424  *
2425  * As a convenience, av_samples_get_buffer_size() and
2426  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2427  * functions to find the required data size and to fill data pointers and
2428  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2429  * since all planes must be the same size.
2430  *
2431  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2432  *
2433  * - encoding: unused
2434  * - decoding: Set by libavcodec, user can override.
2435  */
2437 
2438  /**
2439  * If non-zero, the decoded audio and video frames returned from
2440  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2441  * and are valid indefinitely. The caller must free them with
2442  * av_frame_unref() when they are not needed anymore.
2443  * Otherwise, the decoded frames must not be freed by the caller and are
2444  * only valid until the next decode call.
2445  *
2446  * This is always automatically enabled if avcodec_receive_frame() is used.
2447  *
2448  * - encoding: unused
2449  * - decoding: set by the caller before avcodec_open2().
2450  */
2453 
2454  /* - encoding parameters */
2455  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2456  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2457 
2458  /**
2459  * minimum quantizer
2460  * - encoding: Set by user.
2461  * - decoding: unused
2462  */
2463  int qmin;
2464 
2465  /**
2466  * maximum quantizer
2467  * - encoding: Set by user.
2468  * - decoding: unused
2469  */
2470  int qmax;
2471 
2472  /**
2473  * maximum quantizer difference between frames
2474  * - encoding: Set by user.
2475  * - decoding: unused
2476  */
2478 
2479  /**
2480  * decoder bitstream buffer size
2481  * - encoding: Set by user.
2482  * - decoding: unused
2483  */
2485 
2486  /**
2487  * ratecontrol override, see RcOverride
2488  * - encoding: Allocated/set/freed by user.
2489  * - decoding: unused
2490  */
2493 
2494  /**
2495  * maximum bitrate
2496  * - encoding: Set by user.
2497  * - decoding: Set by user, may be overwritten by libavcodec.
2498  */
2499  int64_t rc_max_rate;
2500 
2501  /**
2502  * minimum bitrate
2503  * - encoding: Set by user.
2504  * - decoding: unused
2505  */
2506  int64_t rc_min_rate;
2507 
2508  /**
2509  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2510  * - encoding: Set by user.
2511  * - decoding: unused.
2512  */
2514 
2515  /**
2516  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2517  * - encoding: Set by user.
2518  * - decoding: unused.
2519  */
2521 
2522  /**
2523  * Number of bits which should be loaded into the rc buffer before decoding starts.
2524  * - encoding: Set by user.
2525  * - decoding: unused
2526  */
2528 
2529 #if FF_API_CODER_TYPE
2530 #define FF_CODER_TYPE_VLC 0
2531 #define FF_CODER_TYPE_AC 1
2532 #define FF_CODER_TYPE_RAW 2
2533 #define FF_CODER_TYPE_RLE 3
2534  /**
2535  * @deprecated use encoder private options instead
2536  */
2539 #endif /* FF_API_CODER_TYPE */
2540 
2541 #if FF_API_PRIVATE_OPT
2542  /** @deprecated use encoder private options instead */
2545 #endif
2546 
2547 #if FF_API_PRIVATE_OPT
2548  /** @deprecated use encoder private options instead */
2551 
2552  /** @deprecated use encoder private options instead */
2555 
2556  /** @deprecated use encoder private options instead */
2559 
2560  /** @deprecated use encoder private options instead */
2563 #endif /* FF_API_PRIVATE_OPT */
2564 
2565  /**
2566  * trellis RD quantization
2567  * - encoding: Set by user.
2568  * - decoding: unused
2569  */
2570  int trellis;
2571 
2572 #if FF_API_PRIVATE_OPT
2573  /** @deprecated use encoder private options instead */
2576 
2577  /** @deprecated use encoder private options instead */
2580 
2581  /** @deprecated use encoder private options instead */
2584 #endif
2585 
2586 #if FF_API_RTP_CALLBACK
2587  /**
2588  * @deprecated unused
2589  */
2590  /* The RTP callback: This function is called */
2591  /* every time the encoder has a packet to send. */
2592  /* It depends on the encoder if the data starts */
2593  /* with a Start Code (it should). H.263 does. */
2594  /* mb_nb contains the number of macroblocks */
2595  /* encoded in the RTP payload. */
2597  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2598 #endif
2599 
2600 #if FF_API_PRIVATE_OPT
2601  /** @deprecated use encoder private options instead */
2603  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2604  /* do its best to deliver a chunk with size */
2605  /* below rtp_payload_size, the chunk will start */
2606  /* with a start code on some codecs like H.263. */
2607  /* This doesn't take account of any particular */
2608  /* headers inside the transmitted RTP payload. */
2609 #endif
2610 
2611 #if FF_API_STAT_BITS
2612  /* statistics, used for 2-pass encoding */
2614  int mv_bits;
2622  int i_count;
2624  int p_count;
2629 
2630  /** @deprecated this field is unused */
2633 #endif
2634 
2635  /**
2636  * pass1 encoding statistics output buffer
2637  * - encoding: Set by libavcodec.
2638  * - decoding: unused
2639  */
2640  char *stats_out;
2641 
2642  /**
2643  * pass2 encoding statistics input buffer
2644  * Concatenated stuff from stats_out of pass1 should be placed here.
2645  * - encoding: Allocated/set/freed by user.
2646  * - decoding: unused
2647  */
2648  char *stats_in;
2649 
2650  /**
2651  * Work around bugs in encoders which sometimes cannot be detected automatically.
2652  * - encoding: Set by user
2653  * - decoding: Set by user
2654  */
2656 #define FF_BUG_AUTODETECT 1 ///< autodetection
2657 #define FF_BUG_XVID_ILACE 4
2658 #define FF_BUG_UMP4 8
2659 #define FF_BUG_NO_PADDING 16
2660 #define FF_BUG_AMV 32
2661 #define FF_BUG_QPEL_CHROMA 64
2662 #define FF_BUG_STD_QPEL 128
2663 #define FF_BUG_QPEL_CHROMA2 256
2664 #define FF_BUG_DIRECT_BLOCKSIZE 512
2665 #define FF_BUG_EDGE 1024
2666 #define FF_BUG_HPEL_CHROMA 2048
2667 #define FF_BUG_DC_CLIP 4096
2668 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2669 #define FF_BUG_TRUNCATED 16384
2670 #define FF_BUG_IEDGE 32768
2671 
2672  /**
2673  * strictly follow the standard (MPEG-4, ...).
2674  * - encoding: Set by user.
2675  * - decoding: Set by user.
2676  * Setting this to STRICT or higher means the encoder and decoder will
2677  * generally do stupid things, whereas setting it to unofficial or lower
2678  * will mean the encoder might produce output that is not supported by all
2679  * spec-compliant decoders. Decoders don't differentiate between normal,
2680  * unofficial and experimental (that is, they always try to decode things
2681  * when they can) unless they are explicitly asked to behave stupidly
2682  * (=strictly conform to the specs)
2683  */
2685 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2686 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2687 #define FF_COMPLIANCE_NORMAL 0
2688 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2689 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2690 
2691  /**
2692  * error concealment flags
2693  * - encoding: unused
2694  * - decoding: Set by user.
2695  */
2697 #define FF_EC_GUESS_MVS 1
2698 #define FF_EC_DEBLOCK 2
2699 #define FF_EC_FAVOR_INTER 256
2700 
2701  /**
2702  * debug
2703  * - encoding: Set by user.
2704  * - decoding: Set by user.
2705  */
2706  int debug;
2707 #define FF_DEBUG_PICT_INFO 1
2708 #define FF_DEBUG_RC 2
2709 #define FF_DEBUG_BITSTREAM 4
2710 #define FF_DEBUG_MB_TYPE 8
2711 #define FF_DEBUG_QP 16
2712 #if FF_API_DEBUG_MV
2713 /**
2714  * @deprecated this option does nothing
2715  */
2716 #define FF_DEBUG_MV 32
2717 #endif
2718 #define FF_DEBUG_DCT_COEFF 0x00000040
2719 #define FF_DEBUG_SKIP 0x00000080
2720 #define FF_DEBUG_STARTCODE 0x00000100
2721 #define FF_DEBUG_ER 0x00000400
2722 #define FF_DEBUG_MMCO 0x00000800
2723 #define FF_DEBUG_BUGS 0x00001000
2724 #if FF_API_DEBUG_MV
2725 #define FF_DEBUG_VIS_QP 0x00002000
2726 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2727 #endif
2728 #define FF_DEBUG_BUFFERS 0x00008000
2729 #define FF_DEBUG_THREADS 0x00010000
2730 #define FF_DEBUG_GREEN_MD 0x00800000
2731 #define FF_DEBUG_NOMC 0x01000000
2732 
2733 #if FF_API_DEBUG_MV
2734  /**
2735  * debug
2736  * - encoding: Set by user.
2737  * - decoding: Set by user.
2738  */
2739  int debug_mv;
2740 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2741 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2742 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2743 #endif
2744 
2745  /**
2746  * Error recognition; may misdetect some more or less valid parts as errors.
2747  * - encoding: unused
2748  * - decoding: Set by user.
2749  */
2751 
2752 /**
2753  * Verify checksums embedded in the bitstream (could be of either encoded or
2754  * decoded data, depending on the codec) and print an error message on mismatch.
2755  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2756  * decoder returning an error.
2757  */
2758 #define AV_EF_CRCCHECK (1<<0)
2759 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2760 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2761 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2762 
2763 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2764 #define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
2765 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2766 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2767 
2768 
2769  /**
2770  * opaque 64-bit number (generally a PTS) that will be reordered and
2771  * output in AVFrame.reordered_opaque
2772  * - encoding: Set by libavcodec to the reordered_opaque of the input
2773  * frame corresponding to the last returned packet. Only
2774  * supported by encoders with the
2775  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
2776  * - decoding: Set by user.
2777  */
2779 
2780  /**
2781  * Hardware accelerator in use
2782  * - encoding: unused.
2783  * - decoding: Set by libavcodec
2784  */
2785  const struct AVHWAccel *hwaccel;
2786 
2787  /**
2788  * Hardware accelerator context.
2789  * For some hardware accelerators, a global context needs to be
2790  * provided by the user. In that case, this holds display-dependent
2791  * data FFmpeg cannot instantiate itself. Please refer to the
2792  * FFmpeg HW accelerator documentation to know how to fill this
2793  * is. e.g. for VA API, this is a struct vaapi_context.
2794  * - encoding: unused
2795  * - decoding: Set by user
2796  */
2798 
2799  /**
2800  * error
2801  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2802  * - decoding: unused
2803  */
2805 
2806  /**
2807  * DCT algorithm, see FF_DCT_* below
2808  * - encoding: Set by user.
2809  * - decoding: unused
2810  */
2812 #define FF_DCT_AUTO 0
2813 #define FF_DCT_FASTINT 1
2814 #define FF_DCT_INT 2
2815 #define FF_DCT_MMX 3
2816 #define FF_DCT_ALTIVEC 5
2817 #define FF_DCT_FAAN 6
2818 
2819  /**
2820  * IDCT algorithm, see FF_IDCT_* below.
2821  * - encoding: Set by user.
2822  * - decoding: Set by user.
2823  */
2825 #define FF_IDCT_AUTO 0
2826 #define FF_IDCT_INT 1
2827 #define FF_IDCT_SIMPLE 2
2828 #define FF_IDCT_SIMPLEMMX 3
2829 #define FF_IDCT_ARM 7
2830 #define FF_IDCT_ALTIVEC 8
2831 #define FF_IDCT_SIMPLEARM 10
2832 #define FF_IDCT_XVID 14
2833 #define FF_IDCT_SIMPLEARMV5TE 16
2834 #define FF_IDCT_SIMPLEARMV6 17
2835 #define FF_IDCT_FAAN 20
2836 #define FF_IDCT_SIMPLENEON 22
2837 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2838 #define FF_IDCT_SIMPLEAUTO 128
2839 
2840  /**
2841  * bits per sample/pixel from the demuxer (needed for huffyuv).
2842  * - encoding: Set by libavcodec.
2843  * - decoding: Set by user.
2844  */
2846 
2847  /**
2848  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2849  * - encoding: set by user.
2850  * - decoding: set by libavcodec.
2851  */
2853 
2854 #if FF_API_LOWRES
2855  /**
2856  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2857  * - encoding: unused
2858  * - decoding: Set by user.
2859  */
2860  int lowres;
2861 #endif
2862 
2863 #if FF_API_CODED_FRAME
2864  /**
2865  * the picture in the bitstream
2866  * - encoding: Set by libavcodec.
2867  * - decoding: unused
2868  *
2869  * @deprecated use the quality factor packet side data instead
2870  */
2872 #endif
2873 
2874  /**
2875  * thread count
2876  * is used to decide how many independent tasks should be passed to execute()
2877  * - encoding: Set by user.
2878  * - decoding: Set by user.
2879  */
2881 
2882  /**
2883  * Which multithreading methods to use.
2884  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2885  * so clients which cannot provide future frames should not use it.
2886  *
2887  * - encoding: Set by user, otherwise the default is used.
2888  * - decoding: Set by user, otherwise the default is used.
2889  */
2891 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2892 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2893 
2894  /**
2895  * Which multithreading methods are in use by the codec.
2896  * - encoding: Set by libavcodec.
2897  * - decoding: Set by libavcodec.
2898  */
2900 
2901  /**
2902  * Set by the client if its custom get_buffer() callback can be called
2903  * synchronously from another thread, which allows faster multithreaded decoding.
2904  * draw_horiz_band() will be called from other threads regardless of this setting.
2905  * Ignored if the default get_buffer() is used.
2906  * - encoding: Set by user.
2907  * - decoding: Set by user.
2908  */
2910 
2911  /**
2912  * The codec may call this to execute several independent things.
2913  * It will return only after finishing all tasks.
2914  * The user may replace this with some multithreaded implementation,
2915  * the default implementation will execute the parts serially.
2916  * @param count the number of things to execute
2917  * - encoding: Set by libavcodec, user can override.
2918  * - decoding: Set by libavcodec, user can override.
2919  */
2920  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2921 
2922  /**
2923  * The codec may call this to execute several independent things.
2924  * It will return only after finishing all tasks.
2925  * The user may replace this with some multithreaded implementation,
2926  * the default implementation will execute the parts serially.
2927  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2928  * @param c context passed also to func
2929  * @param count the number of things to execute
2930  * @param arg2 argument passed unchanged to func
2931  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2932  * @param func function that will be called count times, with jobnr from 0 to count-1.
2933  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2934  * two instances of func executing at the same time will have the same threadnr.
2935  * @return always 0 currently, but code should handle a future improvement where when any call to func
2936  * returns < 0 no further calls to func may be done and < 0 is returned.
2937  * - encoding: Set by libavcodec, user can override.
2938  * - decoding: Set by libavcodec, user can override.
2939  */
2940  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2941 
2942  /**
2943  * noise vs. sse weight for the nsse comparison function
2944  * - encoding: Set by user.
2945  * - decoding: unused
2946  */
2948 
2949  /**
2950  * profile
2951  * - encoding: Set by user.
2952  * - decoding: Set by libavcodec.
2953  */
2954  int profile;
2955 #define FF_PROFILE_UNKNOWN -99
2956 #define FF_PROFILE_RESERVED -100
2957 
2958 #define FF_PROFILE_AAC_MAIN 0
2959 #define FF_PROFILE_AAC_LOW 1
2960 #define FF_PROFILE_AAC_SSR 2
2961 #define FF_PROFILE_AAC_LTP 3
2962 #define FF_PROFILE_AAC_HE 4
2963 #define FF_PROFILE_AAC_HE_V2 28
2964 #define FF_PROFILE_AAC_LD 22
2965 #define FF_PROFILE_AAC_ELD 38
2966 #define FF_PROFILE_MPEG2_AAC_LOW 128
2967 #define FF_PROFILE_MPEG2_AAC_HE 131
2968 
2969 #define FF_PROFILE_DNXHD 0
2970 #define FF_PROFILE_DNXHR_LB 1
2971 #define FF_PROFILE_DNXHR_SQ 2
2972 #define FF_PROFILE_DNXHR_HQ 3
2973 #define FF_PROFILE_DNXHR_HQX 4
2974 #define FF_PROFILE_DNXHR_444 5
2975 
2976 #define FF_PROFILE_DTS 20
2977 #define FF_PROFILE_DTS_ES 30
2978 #define FF_PROFILE_DTS_96_24 40
2979 #define FF_PROFILE_DTS_HD_HRA 50
2980 #define FF_PROFILE_DTS_HD_MA 60
2981 #define FF_PROFILE_DTS_EXPRESS 70
2982 
2983 #define FF_PROFILE_MPEG2_422 0
2984 #define FF_PROFILE_MPEG2_HIGH 1
2985 #define FF_PROFILE_MPEG2_SS 2
2986 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2987 #define FF_PROFILE_MPEG2_MAIN 4
2988 #define FF_PROFILE_MPEG2_SIMPLE 5
2989 
2990 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2991 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2992 
2993 #define FF_PROFILE_H264_BASELINE 66
2994 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2995 #define FF_PROFILE_H264_MAIN 77
2996 #define FF_PROFILE_H264_EXTENDED 88
2997 #define FF_PROFILE_H264_HIGH 100
2998 #define FF_PROFILE_H264_HIGH_10 110
2999 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
3000 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
3001 #define FF_PROFILE_H264_HIGH_422 122
3002 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
3003 #define FF_PROFILE_H264_STEREO_HIGH 128
3004 #define FF_PROFILE_H264_HIGH_444 144
3005 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
3006 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
3007 #define FF_PROFILE_H264_CAVLC_444 44
3008 
3009 #define FF_PROFILE_VC1_SIMPLE 0
3010 #define FF_PROFILE_VC1_MAIN 1
3011 #define FF_PROFILE_VC1_COMPLEX 2
3012 #define FF_PROFILE_VC1_ADVANCED 3
3013 
3014 #define FF_PROFILE_MPEG4_SIMPLE 0
3015 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
3016 #define FF_PROFILE_MPEG4_CORE 2
3017 #define FF_PROFILE_MPEG4_MAIN 3
3018 #define FF_PROFILE_MPEG4_N_BIT 4
3019 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
3020 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
3021 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
3022 #define FF_PROFILE_MPEG4_HYBRID 8
3023 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
3024 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
3025 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
3026 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
3027 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
3028 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
3029 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
3030 
3031 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
3032 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
3033 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
3034 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
3035 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
3036 
3037 #define FF_PROFILE_VP9_0 0
3038 #define FF_PROFILE_VP9_1 1
3039 #define FF_PROFILE_VP9_2 2
3040 #define FF_PROFILE_VP9_3 3
3041 
3042 #define FF_PROFILE_HEVC_MAIN 1
3043 #define FF_PROFILE_HEVC_MAIN_10 2
3044 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
3045 #define FF_PROFILE_HEVC_REXT 4
3046 
3047 #define FF_PROFILE_AV1_MAIN 0
3048 #define FF_PROFILE_AV1_HIGH 1
3049 #define FF_PROFILE_AV1_PROFESSIONAL 2
3050 
3051 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
3052 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
3053 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
3054 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
3055 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
3056 
3057 #define FF_PROFILE_SBC_MSBC 1
3058 
3059 #define FF_PROFILE_PRORES_PROXY 0
3060 #define FF_PROFILE_PRORES_LT 1
3061 #define FF_PROFILE_PRORES_STANDARD 2
3062 #define FF_PROFILE_PRORES_HQ 3
3063 #define FF_PROFILE_PRORES_4444 4
3064 #define FF_PROFILE_PRORES_XQ 5
3065 
3066 #define FF_PROFILE_ARIB_PROFILE_A 0
3067 #define FF_PROFILE_ARIB_PROFILE_C 1
3068 
3069  /**
3070  * level
3071  * - encoding: Set by user.
3072  * - decoding: Set by libavcodec.
3073  */
3074  int level;
3075 #define FF_LEVEL_UNKNOWN -99
3076 
3077  /**
3078  * Skip loop filtering for selected frames.
3079  * - encoding: unused
3080  * - decoding: Set by user.
3081  */
3083 
3084  /**
3085  * Skip IDCT/dequantization for selected frames.
3086  * - encoding: unused
3087  * - decoding: Set by user.
3088  */
3090 
3091  /**
3092  * Skip decoding for selected frames.
3093  * - encoding: unused
3094  * - decoding: Set by user.
3095  */
3097 
3098  /**
3099  * Header containing style information for text subtitles.
3100  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3101  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3102  * the Format line following. It shouldn't include any Dialogue line.
3103  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3104  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3105  */
3108 
3109 #if FF_API_VBV_DELAY
3110  /**
3111  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3112  * Used for compliant TS muxing.
3113  * - encoding: Set by libavcodec.
3114  * - decoding: unused.
3115  * @deprecated this value is now exported as a part of
3116  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3117  */
3119  uint64_t vbv_delay;
3120 #endif
3121 
3122 #if FF_API_SIDEDATA_ONLY_PKT
3123  /**
3124  * Encoding only and set by default. Allow encoders to output packets
3125  * that do not contain any encoded data, only side data.
3126  *
3127  * Some encoders need to output such packets, e.g. to update some stream
3128  * parameters at the end of encoding.
3129  *
3130  * @deprecated this field disables the default behaviour and
3131  * it is kept only for compatibility.
3132  */
3135 #endif
3136 
3137  /**
3138  * Audio only. The number of "priming" samples (padding) inserted by the
3139  * encoder at the beginning of the audio. I.e. this number of leading
3140  * decoded samples must be discarded by the caller to get the original audio
3141  * without leading padding.
3142  *
3143  * - decoding: unused
3144  * - encoding: Set by libavcodec. The timestamps on the output packets are
3145  * adjusted by the encoder so that they always refer to the
3146  * first sample of the data actually contained in the packet,
3147  * including any added padding. E.g. if the timebase is
3148  * 1/samplerate and the timestamp of the first input sample is
3149  * 0, the timestamp of the first output packet will be
3150  * -initial_padding.
3151  */
3153 
3154  /**
3155  * - decoding: For codecs that store a framerate value in the compressed
3156  * bitstream, the decoder may export it here. { 0, 1} when
3157  * unknown.
3158  * - encoding: May be used to signal the framerate of CFR content to an
3159  * encoder.
3160  */
3162 
3163  /**
3164  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3165  * - encoding: unused.
3166  * - decoding: Set by libavcodec before calling get_format()
3167  */
3169 
3170  /**
3171  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3172  * - encoding unused.
3173  * - decoding set by user.
3174  */
3176 
3177  /**
3178  * AVCodecDescriptor
3179  * - encoding: unused.
3180  * - decoding: set by libavcodec.
3181  */
3183 
3184 #if !FF_API_LOWRES
3185  /**
3186  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3187  * - encoding: unused
3188  * - decoding: Set by user.
3189  */
3190  int lowres;
3191 #endif
3192 
3193  /**
3194  * Current statistics for PTS correction.
3195  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3196  * - encoding: unused
3197  */
3198  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3199  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3200  int64_t pts_correction_last_pts; /// PTS of the last frame
3201  int64_t pts_correction_last_dts; /// DTS of the last frame
3202 
3203  /**
3204  * Character encoding of the input subtitles file.
3205  * - decoding: set by user
3206  * - encoding: unused
3207  */
3209 
3210  /**
3211  * Subtitles character encoding mode. Formats or codecs might be adjusting
3212  * this setting (if they are doing the conversion themselves for instance).
3213  * - decoding: set by libavcodec
3214  * - encoding: unused
3215  */
3217 #define FF_SUB_CHARENC_MODE_DO_NOTHING -1 ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
3218 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3219 #define FF_SUB_CHARENC_MODE_PRE_DECODER 1 ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
3220 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
3221 
3222  /**
3223  * Skip processing alpha if supported by codec.
3224  * Note that if the format uses pre-multiplied alpha (common with VP6,
3225  * and recommended due to better video quality/compression)
3226  * the image will look as if alpha-blended onto a black background.
3227  * However for formats that do not use pre-multiplied alpha
3228  * there might be serious artefacts (though e.g. libswscale currently
3229  * assumes pre-multiplied alpha anyway).
3230  *
3231  * - decoding: set by user
3232  * - encoding: unused
3233  */
3235 
3236  /**
3237  * Number of samples to skip after a discontinuity
3238  * - decoding: unused
3239  * - encoding: set by libavcodec
3240  */
3242 
3243 #if !FF_API_DEBUG_MV
3244  /**
3245  * debug motion vectors
3246  * - encoding: Set by user.
3247  * - decoding: Set by user.
3248  */
3250 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3251 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3252 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3253 #endif
3254 
3255  /**
3256  * custom intra quantization matrix
3257  * - encoding: Set by user, can be NULL.
3258  * - decoding: unused.
3259  */
3261 
3262  /**
3263  * dump format separator.
3264  * can be ", " or "\n " or anything else
3265  * - encoding: Set by user.
3266  * - decoding: Set by user.
3267  */
3269 
3270  /**
3271  * ',' separated list of allowed decoders.
3272  * If NULL then all are allowed
3273  * - encoding: unused
3274  * - decoding: set by user
3275  */
3277 
3278  /**
3279  * Properties of the stream that gets decoded
3280  * - encoding: unused
3281  * - decoding: set by libavcodec
3282  */
3283  unsigned properties;
3284 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3285 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3286 
3287  /**
3288  * Additional data associated with the entire coded stream.
3289  *
3290  * - decoding: unused
3291  * - encoding: may be set by libavcodec after avcodec_open2().
3292  */
3295 
3296  /**
3297  * A reference to the AVHWFramesContext describing the input (for encoding)
3298  * or output (decoding) frames. The reference is set by the caller and
3299  * afterwards owned (and freed) by libavcodec - it should never be read by
3300  * the caller after being set.
3301  *
3302  * - decoding: This field should be set by the caller from the get_format()
3303  * callback. The previous reference (if any) will always be
3304  * unreffed by libavcodec before the get_format() call.
3305  *
3306  * If the default get_buffer2() is used with a hwaccel pixel
3307  * format, then this AVHWFramesContext will be used for
3308  * allocating the frame buffers.
3309  *
3310  * - encoding: For hardware encoders configured to use a hwaccel pixel
3311  * format, this field should be set by the caller to a reference
3312  * to the AVHWFramesContext describing input frames.
3313  * AVHWFramesContext.format must be equal to
3314  * AVCodecContext.pix_fmt.
3315  *
3316  * This field should be set before avcodec_open2() is called.
3317  */
3319 
3320  /**
3321  * Control the form of AVSubtitle.rects[N]->ass
3322  * - decoding: set by user
3323  * - encoding: unused
3324  */
3326 #define FF_SUB_TEXT_FMT_ASS 0
3327 #if FF_API_ASS_TIMING
3328 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3329 #endif
3330 
3331  /**
3332  * Audio only. The amount of padding (in samples) appended by the encoder to
3333  * the end of the audio. I.e. this number of decoded samples must be
3334  * discarded by the caller from the end of the stream to get the original
3335  * audio without any trailing padding.
3336  *
3337  * - decoding: unused
3338  * - encoding: unused
3339  */
3341 
3342  /**
3343  * The number of pixels per image to maximally accept.
3344  *
3345  * - decoding: set by user
3346  * - encoding: set by user
3347  */
3348  int64_t max_pixels;
3349 
3350  /**
3351  * A reference to the AVHWDeviceContext describing the device which will
3352  * be used by a hardware encoder/decoder. The reference is set by the
3353  * caller and afterwards owned (and freed) by libavcodec.
3354  *
3355  * This should be used if either the codec device does not require
3356  * hardware frames or any that are used are to be allocated internally by
3357  * libavcodec. If the user wishes to supply any of the frames used as
3358  * encoder input or decoder output then hw_frames_ctx should be used
3359  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3360  * field will be ignored while decoding the associated stream segment, but
3361  * may again be used on a following one after another get_format() call.
3362  *
3363  * For both encoders and decoders this field should be set before
3364  * avcodec_open2() is called and must not be written to thereafter.
3365  *
3366  * Note that some decoders may require this field to be set initially in
3367  * order to support hw_frames_ctx at all - in that case, all frames
3368  * contexts used must be created on the same device.
3369  */
3371 
3372  /**
3373  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3374  * decoding (if active).
3375  * - encoding: unused
3376  * - decoding: Set by user (either before avcodec_open2(), or in the
3377  * AVCodecContext.get_format callback)
3378  */
3380 
3381  /**
3382  * Video decoding only. Certain video codecs support cropping, meaning that
3383  * only a sub-rectangle of the decoded frame is intended for display. This
3384  * option controls how cropping is handled by libavcodec.
3385  *
3386  * When set to 1 (the default), libavcodec will apply cropping internally.
3387  * I.e. it will modify the output frame width/height fields and offset the
3388  * data pointers (only by as much as possible while preserving alignment, or
3389  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3390  * the frames output by the decoder refer only to the cropped area. The
3391  * crop_* fields of the output frames will be zero.
3392  *
3393  * When set to 0, the width/height fields of the output frames will be set
3394  * to the coded dimensions and the crop_* fields will describe the cropping
3395  * rectangle. Applying the cropping is left to the caller.
3396  *
3397  * @warning When hardware acceleration with opaque output frames is used,
3398  * libavcodec is unable to apply cropping from the top/left border.
3399  *
3400  * @note when this option is set to zero, the width/height fields of the
3401  * AVCodecContext and output AVFrames have different meanings. The codec
3402  * context fields store display dimensions (with the coded dimensions in
3403  * coded_width/height), while the frame fields store the coded dimensions
3404  * (with the display dimensions being determined by the crop_* fields).
3405  */
3407 
3408  /*
3409  * Video decoding only. Sets the number of extra hardware frames which
3410  * the decoder will allocate for use by the caller. This must be set
3411  * before avcodec_open2() is called.
3412  *
3413  * Some hardware decoders require all frames that they will use for
3414  * output to be defined in advance before decoding starts. For such
3415  * decoders, the hardware frame pool must therefore be of a fixed size.
3416  * The extra frames set here are on top of any number that the decoder
3417  * needs internally in order to operate normally (for example, frames
3418  * used as reference pictures).
3419  */
3421 
3422  /**
3423  * The percentage of damaged samples to discard a frame.
3424  *
3425  * - decoding: set by user
3426  * - encoding: unused
3427  */
3429 
3430  /**
3431  * The number of samples per frame to maximally accept.
3432  *
3433  * - decoding: set by user
3434  * - encoding: set by user
3435  */
3436  int64_t max_samples;
3437 
3438  /**
3439  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
3440  * metadata exported in frame, packet, or coded stream side data by
3441  * decoders and encoders.
3442  *
3443  * - decoding: set by user
3444  * - encoding: set by user
3445  */
3447 } AVCodecContext;
3448 
3449 #if FF_API_CODEC_GET_SET
3450 /**
3451  * Accessors for some AVCodecContext fields. These used to be provided for ABI
3452  * compatibility, and do not need to be used anymore.
3453  */
3458 
3463 
3465 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3466 
3467 #if FF_API_LOWRES
3469 int av_codec_get_lowres(const AVCodecContext *avctx);
3471 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3472 #endif
3473 
3475 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3477 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3478 
3480 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3482 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3483 #endif
3484 
3485 /**
3486  * AVProfile.
3487  */
3488 typedef struct AVProfile {
3489  int profile;
3490  const char *name; ///< short name for the profile
3491 } AVProfile;
3492 
3493 enum {
3494  /**
3495  * The codec supports this format via the hw_device_ctx interface.
3496  *
3497  * When selecting this format, AVCodecContext.hw_device_ctx should
3498  * have been set to a device of the specified type before calling
3499  * avcodec_open2().
3500  */
3502  /**
3503  * The codec supports this format via the hw_frames_ctx interface.
3504  *
3505  * When selecting this format for a decoder,
3506  * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3507  * context inside the get_format() callback. The frames context
3508  * must have been created on a device of the specified type.
3509  */
3511  /**
3512  * The codec supports this format by some internal method.
3513  *
3514  * This format can be selected without any additional configuration -
3515  * no device or frames context is required.
3516  */
3518  /**
3519  * The codec supports this format by some ad-hoc method.
3520  *
3521  * Additional settings and/or function calls are required. See the
3522  * codec-specific documentation for details. (Methods requiring
3523  * this sort of configuration are deprecated and others should be
3524  * used in preference.)
3525  */
3527 };
3528 
3529 typedef struct AVCodecHWConfig {
3530  /**
3531  * A hardware pixel format which the codec can use.
3532  */
3534  /**
3535  * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3536  * setup methods which can be used with this configuration.
3537  */
3538  int methods;
3539  /**
3540  * The device type associated with the configuration.
3541  *
3542  * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3543  * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3544  */
3546 } AVCodecHWConfig;
3547 
3548 typedef struct AVCodecDefault AVCodecDefault;
3549 
3550 struct AVSubtitle;
3551 
3552 /**
3553  * AVCodec.
3554  */
3555 typedef struct AVCodec {
3556  /**
3557  * Name of the codec implementation.
3558  * The name is globally unique among encoders and among decoders (but an
3559  * encoder and a decoder can share the same name).
3560  * This is the primary way to find a codec from the user perspective.
3561  */
3562  const char *name;
3563  /**
3564  * Descriptive name for the codec, meant to be more human readable than name.
3565  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3566  */
3567  const char *long_name;
3570  /**
3571  * Codec capabilities.
3572  * see AV_CODEC_CAP_*
3573  */
3575  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3576  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3577  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3578  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3579  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3580  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3581  const AVClass *priv_class; ///< AVClass for the private context
3582  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3583 
3584  /**
3585  * Group name of the codec implementation.
3586  * This is a short symbolic name of the wrapper backing this codec. A
3587  * wrapper uses some kind of external implementation for the codec, such
3588  * as an external library, or a codec implementation provided by the OS or
3589  * the hardware.
3590  * If this field is NULL, this is a builtin, libavcodec native codec.
3591  * If non-NULL, this will be the suffix in AVCodec.name in most cases
3592  * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
3593  */
3594  const char *wrapper_name;
3595 
3596  /*****************************************************************
3597  * No fields below this line are part of the public API. They
3598  * may not be used outside of libavcodec and can be changed and
3599  * removed at will.
3600  * New public fields should be added right above.
3601  *****************************************************************
3602  */
3604  struct AVCodec *next;
3605  /**
3606  * @name Frame-level threading support functions
3607  * @{
3608  */
3609  /**
3610  * If defined, called on thread contexts when they are created.
3611  * If the codec allocates writable tables in init(), re-allocate them here.
3612  * priv_data will be set to a copy of the original.
3613  */
3615  /**
3616  * Copy necessary context variables from a previous thread context to the current one.
3617  * If not defined, the next thread will start automatically; otherwise, the codec
3618  * must call ff_thread_finish_setup().
3619  *
3620  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3621  */
3623  /** @} */
3624 
3625  /**
3626  * Private codec-specific defaults.
3627  */
3629 
3630  /**
3631  * Initialize codec static data, called from avcodec_register().
3632  *
3633  * This is not intended for time consuming operations as it is
3634  * run for every codec regardless of that codec being used.
3635  */
3636  void (*init_static_data)(struct AVCodec *codec);
3637 
3639  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3640  const struct AVSubtitle *sub);
3641  /**
3642  * Encode data to an AVPacket.
3643  *
3644  * @param avctx codec context
3645  * @param avpkt output AVPacket (may contain a user-provided buffer)
3646  * @param[in] frame AVFrame containing the raw data to be encoded
3647  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3648  * non-empty packet was returned in avpkt.
3649  * @return 0 on success, negative error code on failure
3650  */
3651  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3652  int *got_packet_ptr);
3653  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3654  int (*close)(AVCodecContext *);
3655  /**
3656  * Encode API with decoupled packet/frame dataflow. The API is the
3657  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3658  * that:
3659  * - never called if the codec is closed or the wrong type,
3660  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3661  * - only one drain frame is ever passed down,
3662  */
3663  int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3664  int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3665 
3666  /**
3667  * Decode API with decoupled packet/frame dataflow. This function is called
3668  * to get one output frame. It should call ff_decode_get_packet() to obtain
3669  * input data.
3670  */
3672  /**
3673  * Flush buffers.
3674  * Will be called when seeking
3675  */
3677  /**
3678  * Internal codec capabilities.
3679  * See FF_CODEC_CAP_* in internal.h
3680  */
3682 
3683  /**
3684  * Decoding only, a comma-separated list of bitstream filters to apply to
3685  * packets before decoding.
3686  */
3687  const char *bsfs;
3688 
3689  /**
3690  * Array of pointers to hardware configurations supported by the codec,
3691  * or NULL if no hardware supported. The array is terminated by a NULL
3692  * pointer.
3693  *
3694  * The user can only access this field via avcodec_get_hw_config().
3695  */
3697 
3698  /**
3699  * List of supported codec_tags, terminated by FF_CODEC_TAGS_END.
3700  */
3701  const uint32_t *codec_tags;
3702 } AVCodec;
3703 
3704 #if FF_API_CODEC_GET_SET
3706 int av_codec_get_max_lowres(const AVCodec *codec);
3707 #endif
3708 
3709 struct MpegEncContext;
3710 
3711 /**
3712  * Retrieve supported hardware configurations for a codec.
3713  *
3714  * Values of index from zero to some maximum return the indexed configuration
3715  * descriptor; all other values return NULL. If the codec does not support
3716  * any hardware configurations then it will always return NULL.
3717  */
3718 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3719 
3720 /**
3721  * @defgroup lavc_hwaccel AVHWAccel
3722  *
3723  * @note Nothing in this structure should be accessed by the user. At some
3724  * point in future it will not be externally visible at all.
3725  *
3726  * @{
3727  */
3728 typedef struct AVHWAccel {
3729  /**
3730  * Name of the hardware accelerated codec.
3731  * The name is globally unique among encoders and among decoders (but an
3732  * encoder and a decoder can share the same name).
3733  */
3734  const char *name;
3735 
3736  /**
3737  * Type of codec implemented by the hardware accelerator.
3738  *
3739  * See AVMEDIA_TYPE_xxx
3740  */
3742 
3743  /**
3744  * Codec implemented by the hardware accelerator.
3745  *
3746  * See AV_CODEC_ID_xxx
3747  */
3749 
3750  /**
3751  * Supported pixel format.
3752  *
3753  * Only hardware accelerated formats are supported here.
3754  */
3756 
3757  /**
3758  * Hardware accelerated codec capabilities.
3759  * see AV_HWACCEL_CODEC_CAP_*
3760  */
3762 
3763  /*****************************************************************
3764  * No fields below this line are part of the public API. They
3765  * may not be used outside of libavcodec and can be changed and
3766  * removed at will.
3767  * New public fields should be added right above.
3768  *****************************************************************
3769  */
3770 
3771  /**
3772  * Allocate a custom buffer
3773  */
3775 
3776  /**
3777  * Called at the beginning of each frame or field picture.
3778  *
3779  * Meaningful frame information (codec specific) is guaranteed to
3780  * be parsed at this point. This function is mandatory.
3781  *
3782  * Note that buf can be NULL along with buf_size set to 0.
3783  * Otherwise, this means the whole frame is available at this point.
3784  *
3785  * @param avctx the codec context
3786  * @param buf the frame data buffer base
3787  * @param buf_size the size of the frame in bytes
3788  * @return zero if successful, a negative value otherwise
3789  */
3790  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3791 
3792  /**
3793  * Callback for parameter data (SPS/PPS/VPS etc).
3794  *
3795  * Useful for hardware decoders which keep persistent state about the
3796  * video parameters, and need to receive any changes to update that state.
3797  *
3798  * @param avctx the codec context
3799  * @param type the nal unit type
3800  * @param buf the nal unit data buffer
3801  * @param buf_size the size of the nal unit in bytes
3802  * @return zero if successful, a negative value otherwise
3803  */
3804  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3805 
3806  /**
3807  * Callback for each slice.
3808  *
3809  * Meaningful slice information (codec specific) is guaranteed to
3810  * be parsed at this point. This function is mandatory.
3811  * The only exception is XvMC, that works on MB level.
3812  *
3813  * @param avctx the codec context
3814  * @param buf the slice data buffer base
3815  * @param buf_size the size of the slice in bytes
3816  * @return zero if successful, a negative value otherwise
3817  */
3818  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3819 
3820  /**
3821  * Called at the end of each frame or field picture.
3822  *
3823  * The whole picture is parsed at this point and can now be sent
3824  * to the hardware accelerator. This function is mandatory.
3825  *
3826  * @param avctx the codec context
3827  * @return zero if successful, a negative value otherwise
3828  */
3829  int (*end_frame)(AVCodecContext *avctx);
3830 
3831  /**
3832  * Size of per-frame hardware accelerator private data.
3833  *
3834  * Private data is allocated with av_mallocz() before
3835  * AVCodecContext.get_buffer() and deallocated after
3836  * AVCodecContext.release_buffer().
3837  */
3839 
3840  /**
3841  * Called for every Macroblock in a slice.
3842  *
3843  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3844  * Instead of decoding to raw picture, MB parameters are
3845  * stored in an array provided by the video driver.
3846  *
3847  * @param s the mpeg context
3848  */
3850 
3851  /**
3852  * Initialize the hwaccel private data.
3853  *
3854  * This will be called from ff_get_format(), after hwaccel and
3855  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3856  * is allocated.
3857  */
3859 
3860  /**
3861  * Uninitialize the hwaccel private data.
3862  *
3863  * This will be called from get_format() or avcodec_close(), after hwaccel
3864  * and hwaccel_context are already uninitialized.
3865  */
3867 
3868  /**
3869  * Size of the private data to allocate in
3870  * AVCodecInternal.hwaccel_priv_data.
3871  */
3873 
3874  /**
3875  * Internal hwaccel capabilities.
3876  */
3878 
3879  /**
3880  * Fill the given hw_frames context with current codec parameters. Called
3881  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3882  * details.
3883  *
3884  * This CAN be called before AVHWAccel.init is called, and you must assume
3885  * that avctx->hwaccel_priv_data is invalid.
3886  */
3887  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
3888 } AVHWAccel;
3889 
3890 /**
3891  * HWAccel is experimental and is thus avoided in favor of non experimental
3892  * codecs
3893  */
3894 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3895 
3896 /**
3897  * Hardware acceleration should be used for decoding even if the codec level
3898  * used is unknown or higher than the maximum supported level reported by the
3899  * hardware driver.
3900  *
3901  * It's generally a good idea to pass this flag unless you have a specific
3902  * reason not to, as hardware tends to under-report supported levels.
3903  */
3904 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3905 
3906 /**
3907  * Hardware acceleration can output YUV pixel formats with a different chroma
3908  * sampling than 4:2:0 and/or other than 8 bits per component.
3909  */
3910 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3911 
3912 /**
3913  * Hardware acceleration should still be attempted for decoding when the
3914  * codec profile does not match the reported capabilities of the hardware.
3915  *
3916  * For example, this can be used to try to decode baseline profile H.264
3917  * streams in hardware - it will often succeed, because many streams marked
3918  * as baseline profile actually conform to constrained baseline profile.
3919  *
3920  * @warning If the stream is actually not supported then the behaviour is
3921  * undefined, and may include returning entirely incorrect output
3922  * while indicating success.
3923  */
3924 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3925 
3926 /**
3927  * @}
3928  */
3929 
3930 #if FF_API_AVPICTURE
3931 /**
3932  * @defgroup lavc_picture AVPicture
3933  *
3934  * Functions for working with AVPicture
3935  * @{
3936  */
3937 
3938 /**
3939  * Picture data structure.
3940  *
3941  * Up to four components can be stored into it, the last component is
3942  * alpha.
3943  * @deprecated use AVFrame or imgutils functions instead
3944  */
3945 typedef struct AVPicture {
3947  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3949  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3950 } AVPicture;
3951 
3952 /**
3953  * @}
3954  */
3955 #endif
3956 
3959 
3960  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3961 
3962  /**
3963  * Plain text, the text field must be set by the decoder and is
3964  * authoritative. ass and pict fields may contain approximations.
3965  */
3967 
3968  /**
3969  * Formatted text, the ass field must be set by the decoder and is
3970  * authoritative. pict and text fields may contain approximations.
3971  */
3973 };
3974 
3975 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3976 
3977 typedef struct AVSubtitleRect {
3978  int x; ///< top left corner of pict, undefined when pict is not set
3979  int y; ///< top left corner of pict, undefined when pict is not set
3980  int w; ///< width of pict, undefined when pict is not set
3981  int h; ///< height of pict, undefined when pict is not set
3982  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3983 
3984 #if FF_API_AVPICTURE
3985  /**
3986  * @deprecated unused
3987  */
3990 #endif
3991  /**
3992  * data+linesize for the bitmap of this subtitle.
3993  * Can be set for text/ass as well once they are rendered.
3994  */
3996  int linesize[4];
3997 
3999 
4000  char *text; ///< 0 terminated plain UTF-8 text
4001 
4002  /**
4003  * 0 terminated ASS/SSA compatible event line.
4004  * The presentation of this is unaffected by the other values in this
4005  * struct.
4006  */
4007  char *ass;
4008 
4009  int flags;
4010 } AVSubtitleRect;
4011 
4012 typedef struct AVSubtitle {
4013  uint16_t format; /* 0 = graphics */
4014  uint32_t start_display_time; /* relative to packet pts, in ms */
4015  uint32_t end_display_time; /* relative to packet pts, in ms */
4016  unsigned num_rects;
4018  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
4019 } AVSubtitle;
4020 
4021 /**
4022  * This struct describes the properties of an encoded stream.
4023  *
4024  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
4025  * be allocated with avcodec_parameters_alloc() and freed with
4026  * avcodec_parameters_free().
4027  */
4028 typedef struct AVCodecParameters {
4029  /**
4030  * General type of the encoded data.
4031  */
4033  /**
4034  * Specific type of the encoded data (the codec used).
4035  */
4037  /**
4038  * Additional information about the codec (corresponds to the AVI FOURCC).
4039  */
4040  uint32_t codec_tag;
4041 
4042  /**
4043  * Extra binary data needed for initializing the decoder, codec-dependent.
4044  *
4045  * Must be allocated with av_malloc() and will be freed by
4046  * avcodec_parameters_free(). The allocated size of extradata must be at
4047  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
4048  * bytes zeroed.
4049  */
4051  /**
4052  * Size of the extradata content in bytes.
4053  */
4055 
4056  /**
4057  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
4058  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
4059  */
4060  int format;
4061 
4062  /**
4063  * The average bitrate of the encoded data (in bits per second).
4064  */
4065  int64_t bit_rate;
4066 
4067  /**
4068  * The number of bits per sample in the codedwords.
4069  *
4070  * This is basically the bitrate per sample. It is mandatory for a bunch of
4071  * formats to actually decode them. It's the number of bits for one sample in
4072  * the actual coded bitstream.
4073  *
4074  * This could be for example 4 for ADPCM
4075  * For PCM formats this matches bits_per_raw_sample
4076  * Can be 0
4077  */
4079 
4080  /**
4081  * This is the number of valid bits in each output sample. If the
4082  * sample format has more bits, the least significant bits are additional
4083  * padding bits, which are always 0. Use right shifts to reduce the sample
4084  * to its actual size. For example, audio formats with 24 bit samples will
4085  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
4086  * To get the original sample use "(int32_t)sample >> 8"."
4087  *
4088  * For ADPCM this might be 12 or 16 or similar
4089  * Can be 0
4090  */
4092 
4093  /**
4094  * Codec-specific bitstream restrictions that the stream conforms to.
4095  */
4096  int profile;
4097  int level;
4098 
4099  /**
4100  * Video only. The dimensions of the video frame in pixels.
4101  */
4102  int width;
4103  int height;
4104 
4105  /**
4106  * Video only. The aspect ratio (width / height) which a single pixel
4107  * should have when displayed.
4108  *
4109  * When the aspect ratio is unknown / undefined, the numerator should be
4110  * set to 0 (the denominator may have any value).
4111  */
4113 
4114  /**
4115  * Video only. The order of the fields in interlaced video.
4116  */
4117  enum AVFieldOrder field_order;
4118 
4119  /**
4120  * Video only. Additional colorspace characteristics.
4121  */
4125  enum AVColorSpace color_space;
4126  enum AVChromaLocation chroma_location;
4127 
4128  /**
4129  * Video only. Number of delayed frames.
4130  */
4132 
4133  /**
4134  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4135  * unknown or unspecified, otherwise the number of bits set must be equal to
4136  * the channels field.
4137  */
4138  uint64_t channel_layout;
4139  /**
4140  * Audio only. The number of audio channels.
4141  */
4143  /**
4144  * Audio only. The number of audio samples per second.
4145  */
4147  /**
4148  * Audio only. The number of bytes per coded audio frame, required by some
4149  * formats.
4150  *
4151  * Corresponds to nBlockAlign in WAVEFORMATEX.
4152  */
4154  /**
4155  * Audio only. Audio frame size, if known. Required by some formats to be static.
4156  */
4158 
4159  /**
4160  * Audio only. The amount of padding (in samples) inserted by the encoder at
4161  * the beginning of the audio. I.e. this number of leading decoded samples
4162  * must be discarded by the caller to get the original audio without leading
4163  * padding.
4164  */
4166  /**
4167  * Audio only. The amount of padding (in samples) appended by the encoder to
4168  * the end of the audio. I.e. this number of decoded samples must be
4169  * discarded by the caller from the end of the stream to get the original
4170  * audio without any trailing padding.
4171  */
4173  /**
4174  * Audio only. Number of samples to skip after a discontinuity.
4175  */
4178 
4179 /**
4180  * Iterate over all registered codecs.
4181  *
4182  * @param opaque a pointer where libavcodec will store the iteration state. Must
4183  * point to NULL to start the iteration.
4184  *
4185  * @return the next registered codec or NULL when the iteration is
4186  * finished
4187  */
4188 const AVCodec *av_codec_iterate(void **opaque);
4189 
4190 #if FF_API_NEXT
4191 /**
4192  * If c is NULL, returns the first registered codec,
4193  * if c is non-NULL, returns the next registered codec after c,
4194  * or NULL if c is the last one.
4195  */
4197 AVCodec *av_codec_next(const AVCodec *c);
4198 #endif
4199 
4200 /**
4201  * Return the LIBAVCODEC_VERSION_INT constant.
4202  */
4203 unsigned avcodec_version(void);
4204 
4205 /**
4206  * Return the libavcodec build-time configuration.
4207  */
4208 const char *avcodec_configuration(void);
4209 
4210 /**
4211  * Return the libavcodec license.
4212  */
4213 const char *avcodec_license(void);
4214 
4215 #if FF_API_NEXT
4216 /**
4217  * Register the codec codec and initialize libavcodec.
4218  *
4219  * @warning either this function or avcodec_register_all() must be called
4220  * before any other libavcodec functions.
4221  *
4222  * @see avcodec_register_all()
4223  */
4225 void avcodec_register(AVCodec *codec);
4226 
4227 /**
4228  * Register all the codecs, parsers and bitstream filters which were enabled at
4229  * configuration time. If you do not call this function you can select exactly
4230  * which formats you want to support, by using the individual registration
4231  * functions.
4232  *
4233  * @see avcodec_register
4234  * @see av_register_codec_parser
4235  * @see av_register_bitstream_filter
4236  */
4238 void avcodec_register_all(void);
4239 #endif
4240 
4241 /**
4242  * Allocate an AVCodecContext and set its fields to default values. The
4243  * resulting struct should be freed with avcodec_free_context().
4244  *
4245  * @param codec if non-NULL, allocate private data and initialize defaults
4246  * for the given codec. It is illegal to then call avcodec_open2()
4247  * with a different codec.
4248  * If NULL, then the codec-specific defaults won't be initialized,
4249  * which may result in suboptimal default settings (this is
4250  * important mainly for encoders, e.g. libx264).
4251  *
4252  * @return An AVCodecContext filled with default values or NULL on failure.
4253  */
4255 
4256 /**
4257  * Free the codec context and everything associated with it and write NULL to
4258  * the provided pointer.
4259  */
4260 void avcodec_free_context(AVCodecContext **avctx);
4261 
4262 #if FF_API_GET_CONTEXT_DEFAULTS
4263 /**
4264  * @deprecated This function should not be used, as closing and opening a codec
4265  * context multiple time is not supported. A new codec context should be
4266  * allocated for each new use.
4267  */
4269 #endif
4270 
4271 /**
4272  * Get the AVClass for AVCodecContext. It can be used in combination with
4273  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4274  *
4275  * @see av_opt_find().
4276  */
4277 const AVClass *avcodec_get_class(void);
4278 
4279 #if FF_API_COPY_CONTEXT
4280 /**
4281  * Get the AVClass for AVFrame. It can be used in combination with
4282  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4283  *
4284  * @see av_opt_find().
4285  */
4286 const AVClass *avcodec_get_frame_class(void);
4287 
4288 /**
4289  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4290  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4291  *
4292  * @see av_opt_find().
4293  */
4295 
4296 /**
4297  * Copy the settings of the source AVCodecContext into the destination
4298  * AVCodecContext. The resulting destination codec context will be
4299  * unopened, i.e. you are required to call avcodec_open2() before you
4300  * can use this AVCodecContext to decode/encode video/audio data.
4301  *
4302  * @param dest target codec context, should be initialized with
4303  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4304  * @param src source codec context
4305  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4306  *
4307  * @deprecated The semantics of this function are ill-defined and it should not
4308  * be used. If you need to transfer the stream parameters from one codec context
4309  * to another, use an intermediate AVCodecParameters instance and the
4310  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4311  * functions.
4312  */
4315 #endif
4316 
4317 /**
4318  * Allocate a new AVCodecParameters and set its fields to default values
4319  * (unknown/invalid/0). The returned struct must be freed with
4320  * avcodec_parameters_free().
4321  */
4323 
4324 /**
4325  * Free an AVCodecParameters instance and everything associated with it and
4326  * write NULL to the supplied pointer.
4327  */
4329 
4330 /**
4331  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4332  * replaced with newly allocated duplicates of the corresponding fields in src.
4333  *
4334  * @return >= 0 on success, a negative AVERROR code on failure.
4335  */
4337 
4338 /**
4339  * Fill the parameters struct based on the values from the supplied codec
4340  * context. Any allocated fields in par are freed and replaced with duplicates
4341  * of the corresponding fields in codec.
4342  *
4343  * @return >= 0 on success, a negative AVERROR code on failure
4344  */
4346  const AVCodecContext *codec);
4347 
4348 /**
4349  * Fill the codec context based on the values from the supplied codec
4350  * parameters. Any allocated fields in codec that have a corresponding field in
4351  * par are freed and replaced with duplicates of the corresponding field in par.
4352  * Fields in codec that do not have a counterpart in par are not touched.
4353  *
4354  * @return >= 0 on success, a negative AVERROR code on failure.
4355  */
4357  const AVCodecParameters *par);
4358 
4359 /**
4360  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4361  * function the context has to be allocated with avcodec_alloc_context3().
4362  *
4363  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4364  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4365  * retrieving a codec.
4366  *
4367  * @warning This function is not thread safe!
4368  *
4369  * @note Always call this function before using decoding routines (such as
4370  * @ref avcodec_receive_frame()).
4371  *
4372  * @code
4373  * avcodec_register_all();
4374  * av_dict_set(&opts, "b", "2.5M", 0);
4375  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4376  * if (!codec)
4377  * exit(1);
4378  *
4379  * context = avcodec_alloc_context3(codec);
4380  *
4381  * if (avcodec_open2(context, codec, opts) < 0)
4382  * exit(1);
4383  * @endcode
4384  *
4385  * @param avctx The context to initialize.
4386  * @param codec The codec to open this context for. If a non-NULL codec has been
4387  * previously passed to avcodec_alloc_context3() or
4388  * for this context, then this parameter MUST be either NULL or
4389  * equal to the previously passed codec.
4390  * @param options A dictionary filled with AVCodecContext and codec-private options.
4391  * On return this object will be filled with options that were not found.
4392  *
4393  * @return zero on success, a negative value on error
4394  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4395  * av_dict_set(), av_opt_find().
4396  */
4397 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4398 
4399 /**
4400  * Close a given AVCodecContext and free all the data associated with it
4401  * (but not the AVCodecContext itself).
4402  *
4403  * Calling this function on an AVCodecContext that hasn't been opened will free
4404  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4405  * codec. Subsequent calls will do nothing.
4406  *
4407  * @note Do not use this function. Use avcodec_free_context() to destroy a
4408  * codec context (either open or closed). Opening and closing a codec context
4409  * multiple times is not supported anymore -- use multiple codec contexts
4410  * instead.
4411  */
4412 int avcodec_close(AVCodecContext *avctx);
4413 
4414 /**
4415  * Free all allocated data in the given subtitle struct.
4416  *
4417  * @param sub AVSubtitle to free.
4418  */
4419 void avsubtitle_free(AVSubtitle *sub);
4420 
4421 /**
4422  * @}
4423  */
4424 
4425 /**
4426  * @addtogroup lavc_packet
4427  * @{
4428  */
4429 
4430 /**
4431  * Allocate an AVPacket and set its fields to default values. The resulting
4432  * struct must be freed using av_packet_free().
4433  *
4434  * @return An AVPacket filled with default values or NULL on failure.
4435  *
4436  * @note this only allocates the AVPacket itself, not the data buffers. Those
4437  * must be allocated through other means such as av_new_packet.
4438  *
4439  * @see av_new_packet
4440  */
4441 AVPacket *av_packet_alloc(void);
4442 
4443 /**
4444  * Create a new packet that references the same data as src.
4445  *
4446  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4447  *
4448  * @return newly created AVPacket on success, NULL on error.
4449  *
4450  * @see av_packet_alloc
4451  * @see av_packet_ref
4452  */
4454 
4455 /**
4456  * Free the packet, if the packet is reference counted, it will be
4457  * unreferenced first.
4458  *
4459  * @param pkt packet to be freed. The pointer will be set to NULL.
4460  * @note passing NULL is a no-op.
4461  */
4462 void av_packet_free(AVPacket **pkt);
4463 
4464 /**
4465  * Initialize optional fields of a packet with default values.
4466  *
4467  * Note, this does not touch the data and size members, which have to be
4468  * initialized separately.
4469  *
4470  * @param pkt packet
4471  */
4472 void av_init_packet(AVPacket *pkt);
4473 
4474 /**
4475  * Allocate the payload of a packet and initialize its fields with
4476  * default values.
4477  *
4478  * @param pkt packet
4479  * @param size wanted payload size
4480  * @return 0 if OK, AVERROR_xxx otherwise
4481  */
4482 int av_new_packet(AVPacket *pkt, int size);
4483 
4484 /**
4485  * Reduce packet size, correctly zeroing padding
4486  *
4487  * @param pkt packet
4488  * @param size new size
4489  */
4490 void av_shrink_packet(AVPacket *pkt, int size);
4491 
4492 /**
4493  * Increase packet size, correctly zeroing padding
4494  *
4495  * @param pkt packet
4496  * @param grow_by number of bytes by which to increase the size of the packet
4497  */
4498 int av_grow_packet(AVPacket *pkt, int grow_by);
4499 
4500 /**
4501  * Initialize a reference-counted packet from av_malloc()ed data.
4502  *
4503  * @param pkt packet to be initialized. This function will set the data, size,
4504  * and buf fields, all others are left untouched.
4505  * @param data Data allocated by av_malloc() to be used as packet data. If this
4506  * function returns successfully, the data is owned by the underlying AVBuffer.
4507  * The caller may not access the data through other means.
4508  * @param size size of data in bytes, without the padding. I.e. the full buffer
4509  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4510  *
4511  * @return 0 on success, a negative AVERROR on error
4512  */
4514 
4515 #if FF_API_AVPACKET_OLD_API
4516 /**
4517  * @warning This is a hack - the packet memory allocation stuff is broken. The
4518  * packet is allocated if it was not really allocated.
4519  *
4520  * @deprecated Use av_packet_ref or av_packet_make_refcounted
4521  */
4523 int av_dup_packet(AVPacket *pkt);
4524 /**
4525  * Copy packet, including contents
4526  *
4527  * @return 0 on success, negative AVERROR on fail
4528  *
4529  * @deprecated Use av_packet_ref
4530  */
4532 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4533 
4534 /**
4535  * Copy packet side data
4536  *
4537  * @return 0 on success, negative AVERROR on fail
4538  *
4539  * @deprecated Use av_packet_copy_props
4540  */
4542 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4543 
4544 /**
4545  * Free a packet.
4546  *
4547  * @deprecated Use av_packet_unref
4548  *
4549  * @param pkt packet to free
4550  */
4552 void av_free_packet(AVPacket *pkt);
4553 #endif
4554 /**
4555  * Allocate new information of a packet.
4556  *
4557  * @param pkt packet
4558  * @param type side information type
4559  * @param size side information size
4560  * @return pointer to fresh allocated data or NULL otherwise
4561  */
4563  int size);
4564 
4565 /**
4566  * Wrap an existing array as a packet side data.
4567  *
4568  * @param pkt packet
4569  * @param type side information type
4570  * @param data the side data array. It must be allocated with the av_malloc()
4571  * family of functions. The ownership of the data is transferred to
4572  * pkt.
4573  * @param size side information size
4574  * @return a non-negative number on success, a negative AVERROR code on
4575  * failure. On failure, the packet is unchanged and the data remains
4576  * owned by the caller.
4577  */
4579  uint8_t *data, size_t size);
4580 
4581 /**
4582  * Shrink the already allocated side data buffer
4583  *
4584  * @param pkt packet
4585  * @param type side information type
4586  * @param size new side information size
4587  * @return 0 on success, < 0 on failure
4588  */
4590  int size);
4591 
4592 /**
4593  * Get side information from packet.
4594  *
4595  * @param pkt packet
4596  * @param type desired side information type
4597  * @param size pointer for side information size to store (optional)
4598  * @return pointer to data if present or NULL otherwise
4599  */
4601  int *size);
4602 
4603 #if FF_API_MERGE_SD_API
4606 
4609 #endif
4610 
4612 
4613 /**
4614  * Pack a dictionary for use in side_data.
4615  *
4616  * @param dict The dictionary to pack.
4617  * @param size pointer to store the size of the returned data
4618  * @return pointer to data if successful, NULL otherwise
4619  */
4621 /**
4622  * Unpack a dictionary from side_data.
4623  *
4624  * @param data data from side_data
4625  * @param size size of the data
4626  * @param dict the metadata storage dictionary
4627  * @return 0 on success, < 0 on failure
4628  */
4629 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4630 
4631 
4632 /**
4633  * Convenience function to free all the side data stored.
4634  * All the other fields stay untouched.
4635  *
4636  * @param pkt packet
4637  */
4639 
4640 /**
4641  * Setup a new reference to the data described by a given packet
4642  *
4643  * If src is reference-counted, setup dst as a new reference to the
4644  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4645  * data from src into it.
4646  *
4647  * All the other fields are copied from src.
4648  *
4649  * @see av_packet_unref
4650  *
4651  * @param dst Destination packet. Will be completely overwritten.
4652  * @param src Source packet
4653  *
4654  * @return 0 on success, a negative AVERROR on error. On error, dst
4655  * will be blank (as if returned by av_packet_alloc()).
4656  */
4657 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4658 
4659 /**
4660  * Wipe the packet.
4661  *
4662  * Unreference the buffer referenced by the packet and reset the
4663  * remaining packet fields to their default values.
4664  *
4665  * @param pkt The packet to be unreferenced.
4666  */
4668 
4669 /**
4670  * Move every field in src to dst and reset src.
4671  *
4672  * @see av_packet_unref
4673  *
4674  * @param src Source packet, will be reset
4675  * @param dst Destination packet
4676  */
4678 
4679 /**
4680  * Copy only "properties" fields from src to dst.
4681  *
4682  * Properties for the purpose of this function are all the fields
4683  * beside those related to the packet data (buf, data, size)
4684  *
4685  * @param dst Destination packet
4686  * @param src Source packet
4687  *
4688  * @return 0 on success AVERROR on failure.
4689  */
4690 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4691 
4692 /**
4693  * Ensure the data described by a given packet is reference counted.
4694  *
4695  * @note This function does not ensure that the reference will be writable.
4696  * Use av_packet_make_writable instead for that purpose.
4697  *
4698  * @see av_packet_ref
4699  * @see av_packet_make_writable
4700  *
4701  * @param pkt packet whose data should be made reference counted.
4702  *
4703  * @return 0 on success, a negative AVERROR on error. On failure, the
4704  * packet is unchanged.
4705  */
4707 
4708 /**
4709  * Create a writable reference for the data described by a given packet,
4710  * avoiding data copy if possible.
4711  *
4712  * @param pkt Packet whose data should be made writable.
4713  *
4714  * @return 0 on success, a negative AVERROR on failure. On failure, the
4715  * packet is unchanged.
4716  */
4718 
4719 /**
4720  * Convert valid timing fields (timestamps / durations) in a packet from one
4721  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4722  * ignored.
4723  *
4724  * @param pkt packet on which the conversion will be performed
4725  * @param tb_src source timebase, in which the timing fields in pkt are
4726  * expressed
4727  * @param tb_dst destination timebase, to which the timing fields will be
4728  * converted
4729  */
4730 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4731 
4732 /**
4733  * @}
4734  */
4735 
4736 /**
4737  * @addtogroup lavc_decoding
4738  * @{
4739  */
4740 
4741 /**
4742  * Find a registered decoder with a matching codec ID.
4743  *
4744  * @param id AVCodecID of the requested decoder
4745  * @return A decoder if one was found, NULL otherwise.
4746  */
4748 
4749 /**
4750  * Find a registered decoder with the specified name.
4751  *
4752  * @param name name of the requested decoder
4753  * @return A decoder if one was found, NULL otherwise.
4754  */
4756 
4757 /**
4758  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4759  * it can be called by custom get_buffer2() implementations for decoders without
4760  * AV_CODEC_CAP_DR1 set.
4761  */
4763 
4764 /**
4765  * Modify width and height values so that they will result in a memory
4766  * buffer that is acceptable for the codec if you do not use any horizontal
4767  * padding.
4768  *
4769  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4770  */
4772 
4773 /**
4774  * Modify width and height values so that they will result in a memory
4775  * buffer that is acceptable for the codec if you also ensure that all
4776  * line sizes are a multiple of the respective linesize_align[i].
4777  *
4778  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4779  */
4781  int linesize_align[AV_NUM_DATA_POINTERS]);
4782 
4783 /**
4784  * Converts AVChromaLocation to swscale x/y chroma position.
4785  *
4786  * The positions represent the chroma (0,0) position in a coordinates system
4787  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4788  *
4789  * @param xpos horizontal chroma sample position
4790  * @param ypos vertical chroma sample position
4791  */
4792 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4793 
4794 /**
4795  * Converts swscale x/y chroma position to AVChromaLocation.
4796  *
4797  * The positions represent the chroma (0,0) position in a coordinates system
4798  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4799  *
4800  * @param xpos horizontal chroma sample position
4801  * @param ypos vertical chroma sample position
4802  */
4803 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4804 
4805 /**
4806  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4807  *
4808  * Some decoders may support multiple frames in a single AVPacket. Such
4809  * decoders would then just decode the first frame and the return value would be
4810  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4811  * called again with an AVPacket containing the remaining data in order to
4812  * decode the second frame, etc... Even if no frames are returned, the packet
4813  * needs to be fed to the decoder with remaining data until it is completely
4814  * consumed or an error occurs.
4815  *
4816  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4817  * and output. This means that for some packets they will not immediately
4818  * produce decoded output and need to be flushed at the end of decoding to get
4819  * all the decoded data. Flushing is done by calling this function with packets
4820  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4821  * returning samples. It is safe to flush even those decoders that are not
4822  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4823  *
4824  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4825  * larger than the actual read bytes because some optimized bitstream
4826  * readers read 32 or 64 bits at once and could read over the end.
4827  *
4828  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4829  * before packets may be fed to the decoder.
4830  *
4831  * @param avctx the codec context
4832  * @param[out] frame The AVFrame in which to store decoded audio samples.
4833  * The decoder will allocate a buffer for the decoded frame by
4834  * calling the AVCodecContext.get_buffer2() callback.
4835  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4836  * reference counted and the returned reference belongs to the
4837  * caller. The caller must release the frame using av_frame_unref()
4838  * when the frame is no longer needed. The caller may safely write
4839  * to the frame if av_frame_is_writable() returns 1.
4840  * When AVCodecContext.refcounted_frames is set to 0, the returned
4841  * reference belongs to the decoder and is valid only until the
4842  * next call to this function or until closing or flushing the
4843  * decoder. The caller may not write to it.
4844  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4845  * non-zero. Note that this field being set to zero
4846  * does not mean that an error has occurred. For
4847  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4848  * call is guaranteed to produce a frame.
4849  * @param[in] avpkt The input AVPacket containing the input buffer.
4850  * At least avpkt->data and avpkt->size should be set. Some
4851  * decoders might also require additional fields to be set.
4852  * @return A negative error code is returned if an error occurred during
4853  * decoding, otherwise the number of bytes consumed from the input
4854  * AVPacket is returned.
4855  *
4856 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4857  */
4860  int *got_frame_ptr, const AVPacket *avpkt);
4861 
4862 /**
4863  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4864  * Some decoders may support multiple frames in a single AVPacket, such
4865  * decoders would then just decode the first frame.
4866  *
4867  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4868  * the actual read bytes because some optimized bitstream readers read 32 or 64
4869  * bits at once and could read over the end.
4870  *
4871  * @warning The end of the input buffer buf should be set to 0 to ensure that
4872  * no overreading happens for damaged MPEG streams.
4873  *
4874  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4875  * between input and output, these need to be fed with avpkt->data=NULL,
4876  * avpkt->size=0 at the end to return the remaining frames.
4877  *
4878  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4879  * before packets may be fed to the decoder.
4880  *
4881  * @param avctx the codec context
4882  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4883  * Use av_frame_alloc() to get an AVFrame. The codec will
4884  * allocate memory for the actual bitmap by calling the
4885  * AVCodecContext.get_buffer2() callback.
4886  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4887  * reference counted and the returned reference belongs to the
4888  * caller. The caller must release the frame using av_frame_unref()
4889  * when the frame is no longer needed. The caller may safely write
4890  * to the frame if av_frame_is_writable() returns 1.
4891  * When AVCodecContext.refcounted_frames is set to 0, the returned
4892  * reference belongs to the decoder and is valid only until the
4893  * next call to this function or until closing or flushing the
4894  * decoder. The caller may not write to it.
4895  *
4896  * @param[in] avpkt The input AVPacket containing the input buffer.
4897  * You can create such packet with av_init_packet() and by then setting
4898  * data and size, some decoders might in addition need other fields like
4899  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4900  * fields possible.
4901  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4902  * @return On error a negative value is returned, otherwise the number of bytes
4903  * used or zero if no frame could be decompressed.
4904  *
4905  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4906  */
4908 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4909  int *got_picture_ptr,
4910  const AVPacket *avpkt);
4911 
4912 /**
4913  * Decode a subtitle message.
4914  * Return a negative value on error, otherwise return the number of bytes used.
4915  * If no subtitle could be decompressed, got_sub_ptr is zero.
4916  * Otherwise, the subtitle is stored in *sub.
4917  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4918  * simplicity, because the performance difference is expected to be negligible
4919  * and reusing a get_buffer written for video codecs would probably perform badly
4920  * due to a potentially very different allocation pattern.
4921  *
4922  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4923  * and output. This means that for some packets they will not immediately
4924  * produce decoded output and need to be flushed at the end of decoding to get
4925  * all the decoded data. Flushing is done by calling this function with packets
4926  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4927  * returning subtitles. It is safe to flush even those decoders that are not
4928  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4929  *
4930  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4931  * before packets may be fed to the decoder.
4932  *
4933  * @param avctx the codec context
4934  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
4935  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4936  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4937  * @param[in] avpkt The input AVPacket containing the input buffer.
4938  */
4940  int *got_sub_ptr,
4941  AVPacket *avpkt);
4942 
4943 /**
4944  * Supply raw packet data as input to a decoder.
4945  *
4946  * Internally, this call will copy relevant AVCodecContext fields, which can
4947  * influence decoding per-packet, and apply them when the packet is actually
4948  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4949  * decoder to drop the frame contained by the packet sent with this function.)
4950  *
4951  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4952  * larger than the actual read bytes because some optimized bitstream
4953  * readers read 32 or 64 bits at once and could read over the end.
4954  *
4955  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4956  * on the same AVCodecContext. It will return unexpected results now
4957  * or in future libavcodec versions.
4958  *
4959  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4960  * before packets may be fed to the decoder.
4961  *
4962  * @param avctx codec context
4963  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4964  * frame, or several complete audio frames.
4965  * Ownership of the packet remains with the caller, and the
4966  * decoder will not write to the packet. The decoder may create
4967  * a reference to the packet data (or copy it if the packet is
4968  * not reference-counted).
4969  * Unlike with older APIs, the packet is always fully consumed,
4970  * and if it contains multiple frames (e.g. some audio codecs),
4971  * will require you to call avcodec_receive_frame() multiple
4972  * times afterwards before you can send a new packet.
4973  * It can be NULL (or an AVPacket with data set to NULL and
4974  * size set to 0); in this case, it is considered a flush
4975  * packet, which signals the end of the stream. Sending the
4976  * first flush packet will return success. Subsequent ones are
4977  * unnecessary and will return AVERROR_EOF. If the decoder
4978  * still has frames buffered, it will return them after sending
4979  * a flush packet.
4980  *
4981  * @return 0 on success, otherwise negative error code:
4982  * AVERROR(EAGAIN): input is not accepted in the current state - user
4983  * must read output with avcodec_receive_frame() (once
4984  * all output is read, the packet should be resent, and
4985  * the call will not fail with EAGAIN).
4986  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4987  * be sent to it (also returned if more than 1 flush
4988  * packet is sent)
4989  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4990  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4991  * other errors: legitimate decoding errors
4992  */
4993 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4994 
4995 /**
4996  * Return decoded output data from a decoder.
4997  *
4998  * @param avctx codec context
4999  * @param frame This will be set to a reference-counted video or audio
5000  * frame (depending on the decoder type) allocated by the
5001  * decoder. Note that the function will always call
5002  * av_frame_unref(frame) before doing anything else.
5003  *
5004  * @return
5005  * 0: success, a frame was returned
5006  * AVERROR(EAGAIN): output is not available in this state - user must try
5007  * to send new input
5008  * AVERROR_EOF: the decoder has been fully flushed, and there will be
5009  * no more output frames
5010  * AVERROR(EINVAL): codec not opened, or it is an encoder
5011  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
5012  * with respect to first decoded frame. Applicable
5013  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
5014  * other negative values: legitimate decoding errors
5015  */
5017 
5018 /**
5019  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
5020  * to retrieve buffered output packets.
5021  *
5022  * @param avctx codec context
5023  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
5024  * Ownership of the frame remains with the caller, and the
5025  * encoder will not write to the frame. The encoder may create
5026  * a reference to the frame data (or copy it if the frame is
5027  * not reference-counted).
5028  * It can be NULL, in which case it is considered a flush
5029  * packet. This signals the end of the stream. If the encoder
5030  * still has packets buffered, it will return them after this
5031  * call. Once flushing mode has been entered, additional flush
5032  * packets are ignored, and sending frames will return
5033  * AVERROR_EOF.
5034  *
5035  * For audio:
5036  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5037  * can have any number of samples.
5038  * If it is not set, frame->nb_samples must be equal to
5039  * avctx->frame_size for all frames except the last.
5040  * The final frame may be smaller than avctx->frame_size.
5041  * @return 0 on success, otherwise negative error code:
5042  * AVERROR(EAGAIN): input is not accepted in the current state - user
5043  * must read output with avcodec_receive_packet() (once
5044  * all output is read, the packet should be resent, and
5045  * the call will not fail with EAGAIN).
5046  * AVERROR_EOF: the encoder has been flushed, and no new frames can
5047  * be sent to it
5048  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
5049  * decoder, or requires flush
5050  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
5051  * other errors: legitimate encoding errors
5052  */
5053 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
5054 
5055 /**
5056  * Read encoded data from the encoder.
5057  *
5058  * @param avctx codec context
5059  * @param avpkt This will be set to a reference-counted packet allocated by the
5060  * encoder. Note that the function will always call
5061  * av_packet_unref(avpkt) before doing anything else.
5062  * @return 0 on success, otherwise negative error code:
5063  * AVERROR(EAGAIN): output is not available in the current state - user
5064  * must try to send input
5065  * AVERROR_EOF: the encoder has been fully flushed, and there will be
5066  * no more output packets
5067  * AVERROR(EINVAL): codec not opened, or it is a decoder
5068  * other errors: legitimate encoding errors
5069  */
5070 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
5071 
5072 /**
5073  * Create and return a AVHWFramesContext with values adequate for hardware
5074  * decoding. This is meant to get called from the get_format callback, and is
5075  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
5076  * This API is for decoding with certain hardware acceleration modes/APIs only.
5077  *
5078  * The returned AVHWFramesContext is not initialized. The caller must do this
5079  * with av_hwframe_ctx_init().
5080  *
5081  * Calling this function is not a requirement, but makes it simpler to avoid
5082  * codec or hardware API specific details when manually allocating frames.
5083  *
5084  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
5085  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
5086  * it unnecessary to call this function or having to care about
5087  * AVHWFramesContext initialization at all.
5088  *
5089  * There are a number of requirements for calling this function:
5090  *
5091  * - It must be called from get_format with the same avctx parameter that was
5092  * passed to get_format. Calling it outside of get_format is not allowed, and
5093  * can trigger undefined behavior.
5094  * - The function is not always supported (see description of return values).
5095  * Even if this function returns successfully, hwaccel initialization could
5096  * fail later. (The degree to which implementations check whether the stream
5097  * is actually supported varies. Some do this check only after the user's
5098  * get_format callback returns.)
5099  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
5100  * user decides to use a AVHWFramesContext prepared with this API function,
5101  * the user must return the same hw_pix_fmt from get_format.
5102  * - The device_ref passed to this function must support the given hw_pix_fmt.
5103  * - After calling this API function, it is the user's responsibility to
5104  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
5105  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
5106  * before returning from get_format (this is implied by the normal
5107  * AVCodecContext.hw_frames_ctx API rules).
5108  * - The AVHWFramesContext parameters may change every time time get_format is
5109  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
5110  * you are inherently required to go through this process again on every
5111  * get_format call.
5112  * - It is perfectly possible to call this function without actually using
5113  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
5114  * previously initialized AVHWFramesContext, and calling this API function
5115  * only to test whether the required frame parameters have changed.
5116  * - Fields that use dynamically allocated values of any kind must not be set
5117  * by the user unless setting them is explicitly allowed by the documentation.
5118  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
5119  * the new free callback must call the potentially set previous free callback.
5120  * This API call may set any dynamically allocated fields, including the free
5121  * callback.
5122  *
5123  * The function will set at least the following fields on AVHWFramesContext
5124  * (potentially more, depending on hwaccel API):
5125  *
5126  * - All fields set by av_hwframe_ctx_alloc().
5127  * - Set the format field to hw_pix_fmt.
5128  * - Set the sw_format field to the most suited and most versatile format. (An
5129  * implication is that this will prefer generic formats over opaque formats
5130  * with arbitrary restrictions, if possible.)
5131  * - Set the width/height fields to the coded frame size, rounded up to the
5132  * API-specific minimum alignment.
5133  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
5134  * field to the number of maximum reference surfaces possible with the codec,
5135  * plus 1 surface for the user to work (meaning the user can safely reference
5136  * at most 1 decoded surface at a time), plus additional buffering introduced
5137  * by frame threading. If the hwaccel does not require pre-allocation, the
5138  * field is left to 0, and the decoder will allocate new surfaces on demand
5139  * during decoding.
5140  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
5141  * hardware API.
5142  *
5143  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
5144  * with basic frame parameters set.
5145  *
5146  * The function is stateless, and does not change the AVCodecContext or the
5147  * device_ref AVHWDeviceContext.
5148  *
5149  * @param avctx The context which is currently calling get_format, and which
5150  * implicitly contains all state needed for filling the returned
5151  * AVHWFramesContext properly.
5152  * @param device_ref A reference to the AVHWDeviceContext describing the device
5153  * which will be used by the hardware decoder.
5154  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
5155  * @param out_frames_ref On success, set to a reference to an _uninitialized_
5156  * AVHWFramesContext, created from the given device_ref.
5157  * Fields will be set to values required for decoding.
5158  * Not changed if an error is returned.
5159  * @return zero on success, a negative value on error. The following error codes
5160  * have special semantics:
5161  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
5162  * is always manual, or it is a decoder which does not
5163  * support setting AVCodecContext.hw_frames_ctx at all,
5164  * or it is a software format.
5165  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
5166  * this configuration, or the device_ref is not supported
5167  * for the hwaccel referenced by hw_pix_fmt.
5168  */
5170  AVBufferRef *device_ref,
5172  AVBufferRef **out_frames_ref);
5173 
5174 
5175 
5176 /**
5177  * @defgroup lavc_parsing Frame parsing
5178  * @{
5179  */
5180 
5183  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5184  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5185  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5186 };
5187 
5188 typedef struct AVCodecParserContext {
5189  void *priv_data;
5191  int64_t frame_offset; /* offset of the current frame */
5192  int64_t cur_offset; /* current offset
5193  (incremented by each av_parser_parse()) */
5194  int64_t next_frame_offset; /* offset of the next frame */
5195  /* video info */
5196  int pict_type; /* XXX: Put it back in AVCodecContext. */
5197  /**
5198  * This field is used for proper frame duration computation in lavf.
5199  * It signals, how much longer the frame duration of the current frame
5200  * is compared to normal frame duration.
5201  *
5202  * frame_duration = (1 + repeat_pict) * time_base
5203  *
5204  * It is used by codecs like H.264 to display telecined material.
5205  */
5206  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5207  int64_t pts; /* pts of the current frame */
5208  int64_t dts; /* dts of the current frame */
5209 
5210  /* private data */
5211  int64_t last_pts;
5212  int64_t last_dts;
5214 
5215 #define AV_PARSER_PTS_NB 4
5217  int64_t cur_frame_offset[AV_PARSER_PTS_NB];
5218  int64_t cur_frame_pts[AV_PARSER_PTS_NB];
5219  int64_t cur_frame_dts[AV_PARSER_PTS_NB];
5220 
5221  int flags;
5222 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5223 #define PARSER_FLAG_ONCE 0x0002
5224 /// Set if the parser has a valid file offset
5225 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5226 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5227 
5228  int64_t offset; ///< byte offset from starting packet start
5229  int64_t cur_frame_end[AV_PARSER_PTS_NB];
5230 
5231  /**
5232  * Set by parser to 1 for key frames and 0 for non-key frames.
5233  * It is initialized to -1, so if the parser doesn't set this flag,
5234  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5235  * will be used.
5236  */
5238 
5239 #if FF_API_CONVERGENCE_DURATION
5240  /**
5241  * @deprecated unused
5242  */
5245 #endif
5246 
5247  // Timestamp generation support:
5248  /**
5249  * Synchronization point for start of timestamp generation.
5250  *
5251  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5252  * (default).
5253  *
5254  * For example, this corresponds to presence of H.264 buffering period
5255  * SEI message.
5256  */
5258 
5259  /**
5260  * Offset of the current timestamp against last timestamp sync point in
5261  * units of AVCodecContext.time_base.
5262  *
5263  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5264  * contain a valid timestamp offset.
5265  *
5266  * Note that the timestamp of sync point has usually a nonzero
5267  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5268  * the next frame after timestamp sync point will be usually 1.
5269  *
5270  * For example, this corresponds to H.264 cpb_removal_delay.
5271  */
5273 
5274  /**
5275  * Presentation delay of current frame in units of AVCodecContext.time_base.
5276  *
5277  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5278  * contain valid non-negative timestamp delta (presentation time of a frame
5279  * must not lie in the past).
5280  *
5281  * This delay represents the difference between decoding and presentation
5282  * time of the frame.
5283  *
5284  * For example, this corresponds to H.264 dpb_output_delay.
5285  */
5287 
5288  /**
5289  * Position of the packet in file.
5290  *
5291  * Analogous to cur_frame_pts/dts
5292  */
5293  int64_t cur_frame_pos[AV_PARSER_PTS_NB];
5294 
5295  /**
5296  * Byte position of currently parsed frame in stream.
5297  */
5298  int64_t pos;
5299 
5300  /**
5301  * Previous frame byte position.
5302  */
5303  int64_t last_pos;
5304 
5305  /**
5306  * Duration of the current frame.
5307  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5308  * For all other types, this is in units of AVCodecContext.time_base.
5309  */
5311 
5312  enum AVFieldOrder field_order;
5313 
5314  /**
5315  * Indicate whether a picture is coded as a frame, top field or bottom field.
5316  *
5317  * For example, H.264 field_pic_flag equal to 0 corresponds to
5318  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5319  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5320  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5321  */
5322  enum AVPictureStructure picture_structure;
5323 
5324  /**
5325  * Picture number incremented in presentation or output order.
5326  * This field may be reinitialized at the first picture of a new sequence.
5327  *
5328  * For example, this corresponds to H.264 PicOrderCnt.
5329  */
5331 
5332  /**
5333  * Dimensions of the decoded video intended for presentation.
5334  */
5335  int width;
5336  int height;
5337 
5338  /**
5339  * Dimensions of the coded video.
5340  */
5343 
5344  /**
5345  * The format of the coded data, corresponds to enum AVPixelFormat for video
5346  * and for enum AVSampleFormat for audio.
5347  *
5348  * Note that a decoder can have considerable freedom in how exactly it
5349  * decodes the data, so the format reported here might be different from the
5350  * one returned by a decoder.
5351  */
5352  int format;
5354 
5355 typedef struct AVCodecParser {
5356  int codec_ids[5]; /* several codec IDs are permitted */
5358  int (*parser_init)(AVCodecParserContext *s);
5359  /* This callback never returns an error, a negative value means that
5360  * the frame start was in a previous packet. */
5361  int (*parser_parse)(AVCodecParserContext *s,
5362  AVCodecContext *avctx,
5363  const uint8_t **poutbuf, int *poutbuf_size,
5364  const uint8_t *buf, int buf_size);
5365  void (*parser_close)(AVCodecParserContext *s);
5366  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5368 } AVCodecParser;
5369 
5370 /**
5371  * Iterate over all registered codec parsers.
5372  *
5373  * @param opaque a pointer where libavcodec will store the iteration state. Must
5374  * point to NULL to start the iteration.
5375  *
5376  * @return the next registered codec parser or NULL when the iteration is
5377  * finished
5378  */
5379 const AVCodecParser *av_parser_iterate(void **opaque);
5380 
5383 
5387 
5388 /**
5389  * Parse a packet.
5390  *
5391  * @param s parser context.
5392  * @param avctx codec context.
5393  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5394  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5395  * @param buf input buffer.
5396  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5397  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5398  To signal EOF, this should be 0 (so that the last frame
5399  can be output).
5400  * @param pts input presentation timestamp.
5401  * @param dts input decoding timestamp.
5402  * @param pos input byte position in stream.
5403  * @return the number of bytes of the input bitstream used.
5404  *
5405  * Example:
5406  * @code
5407  * while(in_len){
5408  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5409  * in_data, in_len,
5410  * pts, dts, pos);
5411  * in_data += len;
5412  * in_len -= len;
5413  *
5414  * if(size)
5415  * decode_frame(data, size);
5416  * }
5417  * @endcode
5418  */
5420  AVCodecContext *avctx,
5421  uint8_t **poutbuf, int *poutbuf_size,
5422  const uint8_t *buf, int buf_size,
5423  int64_t pts, int64_t dts,
5424  int64_t pos);
5425 
5426 /**
5427  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5428  * @deprecated use AVBitStreamFilter
5429  */
5431  AVCodecContext *avctx,
5432  uint8_t **poutbuf, int *poutbuf_size,