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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/log.h"
40 #include "libavutil/pixfmt.h"
41 #include "libavutil/rational.h"
42 
43 #include "version.h"
44 
45 /**
46  * @defgroup libavc Encoding/Decoding Library
47  * @{
48  *
49  * @defgroup lavc_decoding Decoding
50  * @{
51  * @}
52  *
53  * @defgroup lavc_encoding Encoding
54  * @{
55  * @}
56  *
57  * @defgroup lavc_codec Codecs
58  * @{
59  * @defgroup lavc_codec_native Native Codecs
60  * @{
61  * @}
62  * @defgroup lavc_codec_wrappers External library wrappers
63  * @{
64  * @}
65  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
66  * @{
67  * @}
68  * @}
69  * @defgroup lavc_internal Internal
70  * @{
71  * @}
72  * @}
73  */
74 
75 /**
76  * @ingroup libavc
77  * @defgroup lavc_encdec send/receive encoding and decoding API overview
78  * @{
79  *
80  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
81  * avcodec_receive_packet() functions provide an encode/decode API, which
82  * decouples input and output.
83  *
84  * The API is very similar for encoding/decoding and audio/video, and works as
85  * follows:
86  * - Set up and open the AVCodecContext as usual.
87  * - Send valid input:
88  * - For decoding, call avcodec_send_packet() to give the decoder raw
89  * compressed data in an AVPacket.
90  * - For encoding, call avcodec_send_frame() to give the decoder an AVFrame
91  * containing uncompressed audio or video.
92  * In both cases, it is recommended that AVPackets and AVFrames are
93  * refcounted, or libavcodec might have to copy the input data. (libavformat
94  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
95  * refcounted AVFrames.)
96  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
97  * functions and process their output:
98  * - For decoding, call avcodec_receive_frame(). On success, it will return
99  * an AVFrame containing uncompressed audio or video data.
100  * - For encoding, call avcodec_receive_packet(). On success, it will return
101  * an AVPacket with a compressed frame.
102  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
103  * AVERROR(EAGAIN) return value means that new input data is required to
104  * return new output. In this case, continue with sending input. For each
105  * input frame/packet, the codec will typically return 1 output frame/packet,
106  * but it can also be 0 or more than 1.
107  *
108  * At the beginning of decoding or encoding, the codec might accept multiple
109  * input frames/packets without returning a frame, until its internal buffers
110  * are filled. This situation is handled transparently if you follow the steps
111  * outlined above.
112  *
113  * End of stream situations. These require "flushing" (aka draining) the codec,
114  * as the codec might buffer multiple frames or packets internally for
115  * performance or out of necessity (consider B-frames).
116  * This is handled as follows:
117  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
118  * or avcodec_send_frame() (encoding) functions. This will enter draining
119  * mode.
120  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
121  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
122  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
123  * - Before decoding can be resumed again, the codec has to be reset with
124  * avcodec_flush_buffers().
125  *
126  * Using the API as outlined above is highly recommended. But it is also
127  * possible to call functions outside of this rigid schema. For example, you can
128  * call avcodec_send_packet() repeatedly without calling
129  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
130  * until the codec's internal buffer has been filled up (which is typically of
131  * size 1 per output frame, after initial input), and then reject input with
132  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
133  * read at least some output.
134  *
135  * Not all codecs will follow a rigid and predictable dataflow; the only
136  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
137  * one end implies that a receive/send call on the other end will succeed. In
138  * general, no codec will permit unlimited buffering of input or output.
139  *
140  * This API replaces the following legacy functions:
141  * - avcodec_decode_video2() and avcodec_decode_audio4():
142  * Use avcodec_send_packet() to feed input to the decoder, then use
143  * avcodec_receive_frame() to receive decoded frames after each packet.
144  * Unlike with the old video decoding API, multiple frames might result from
145  * a packet. For audio, splitting the input packet into frames by partially
146  * decoding packets becomes transparent to the API user. You never need to
147  * feed an AVPacket to the API twice.
148  * Additionally, sending a flush/draining packet is required only once.
149  * - avcodec_encode_video2()/avcodec_encode_audio2():
150  * Use avcodec_send_frame() to feed input to the encoder, then use
151  * avcodec_receive_packet() to receive encoded packets.
152  * Providing user-allocated buffers for avcodec_receive_packet() is not
153  * possible.
154  * - The new API does not handle subtitles yet.
155  *
156  * Mixing new and old function calls on the same AVCodecContext is not allowed,
157  * and will result in undefined behavior.
158  *
159  * Some codecs might require using the new API; using the old API will return
160  * an error when calling it.
161  * @}
162  */
163 
164 /**
165  * @defgroup lavc_core Core functions/structures.
166  * @ingroup libavc
167  *
168  * Basic definitions, functions for querying libavcodec capabilities,
169  * allocating core structures, etc.
170  * @{
171  */
172 
173 
174 /**
175  * Identify the syntax and semantics of the bitstream.
176  * The principle is roughly:
177  * Two decoders with the same ID can decode the same streams.
178  * Two encoders with the same ID can encode compatible streams.
179  * There may be slight deviations from the principle due to implementation
180  * details.
181  *
182  * If you add a codec ID to this list, add it so that
183  * 1. no value of an existing codec ID changes (that would break ABI),
184  * 2. it is as close as possible to similar codecs
185  *
186  * After adding new codec IDs, do not forget to add an entry to the codec
187  * descriptor list and bump libavcodec minor version.
188  */
189 enum AVCodecID {
191 
192  /* video codecs */
194  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
195 #if FF_API_XVMC
196  AV_CODEC_ID_MPEG2VIDEO_XVMC,
197 #endif /* FF_API_XVMC */
332 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
370 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
389 
412 
413  /* various PCM "codecs" */
414  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
446  /* new PCM "codecs" should be added right below this line starting with
447  * an explicit value of for example 0x10800
448  */
449 
450  /* various ADPCM codecs */
482 #if FF_API_VIMA_DECODER
484 #endif
485 
496 
497  /* AMR */
500 
501  /* RealAudio codecs*/
504 
505  /* various DPCM codecs */
510 
512 
513  /* audio codecs */
514  AV_CODEC_ID_MP2 = 0x15000,
515  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
532  AV_CODEC_ID_GSM, ///< as in Berlin toast format
544  AV_CODEC_ID_GSM_MS, /* as found in WAV */
546 #if FF_API_VOXWARE
548 #endif
584 
599 
600  /* subtitle codecs */
601  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
604  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
611 
627 
628  /* other specific kind of codecs (generally used for attachments) */
629  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
630  AV_CODEC_ID_TTF = 0x18000,
631 
640 
641 
642  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
643 
644  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
645  * stream (only used by libavformat) */
646  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
647  * stream (only used by libavformat) */
648  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
649  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
650 };
651 
652 /**
653  * This struct describes the properties of a single codec described by an
654  * AVCodecID.
655  * @see avcodec_descriptor_get()
656  */
657 typedef struct AVCodecDescriptor {
658  enum AVCodecID id;
660  /**
661  * Name of the codec described by this descriptor. It is non-empty and
662  * unique for each codec descriptor. It should contain alphanumeric
663  * characters and '_' only.
664  */
665  const char *name;
666  /**
667  * A more descriptive name for this codec. May be NULL.
668  */
669  const char *long_name;
670  /**
671  * Codec properties, a combination of AV_CODEC_PROP_* flags.
672  */
673  int props;
674  /**
675  * MIME type(s) associated with the codec.
676  * May be NULL; if not, a NULL-terminated array of MIME types.
677  * The first item is always non-NULL and is the preferred MIME type.
678  */
679  const char *const *mime_types;
680  /**
681  * If non-NULL, an array of profiles recognized for this codec.
682  * Terminated with FF_PROFILE_UNKNOWN.
683  */
684  const struct AVProfile *profiles;
686 
687 /**
688  * Codec uses only intra compression.
689  * Video codecs only.
690  */
691 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
692 /**
693  * Codec supports lossy compression. Audio and video codecs only.
694  * @note a codec may support both lossy and lossless
695  * compression modes
696  */
697 #define AV_CODEC_PROP_LOSSY (1 << 1)
698 /**
699  * Codec supports lossless compression. Audio and video codecs only.
700  */
701 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
702 /**
703  * Codec supports frame reordering. That is, the coded order (the order in which
704  * the encoded packets are output by the encoders / stored / input to the
705  * decoders) may be different from the presentation order of the corresponding
706  * frames.
707  *
708  * For codecs that do not have this property set, PTS and DTS should always be
709  * equal.
710  */
711 #define AV_CODEC_PROP_REORDER (1 << 3)
712 /**
713  * Subtitle codec is bitmap based
714  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
715  */
716 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
717 /**
718  * Subtitle codec is text based.
719  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
720  */
721 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
722 
723 /**
724  * @ingroup lavc_decoding
725  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
726  * This is mainly needed because some optimized bitstream readers read
727  * 32 or 64 bit at once and could read over the end.<br>
728  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
729  * MPEG bitstreams could cause overread and segfault.
730  */
731 #define AV_INPUT_BUFFER_PADDING_SIZE 32
732 
733 /**
734  * @ingroup lavc_encoding
735  * minimum encoding buffer size
736  * Used to avoid some checks during header writing.
737  */
738 #define AV_INPUT_BUFFER_MIN_SIZE 16384
739 
740 #if FF_API_WITHOUT_PREFIX
741 /**
742  * @deprecated use AV_INPUT_BUFFER_PADDING_SIZE instead
743  */
744 #define FF_INPUT_BUFFER_PADDING_SIZE 32
745 
746 /**
747  * @deprecated use AV_INPUT_BUFFER_MIN_SIZE instead
748  */
749 #define FF_MIN_BUFFER_SIZE 16384
750 #endif /* FF_API_WITHOUT_PREFIX */
751 
752 /**
753  * @ingroup lavc_encoding
754  * motion estimation type.
755  * @deprecated use codec private option instead
756  */
757 #if FF_API_MOTION_EST
759  ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
763  ME_EPZS, ///< enhanced predictive zonal search
764  ME_X1, ///< reserved for experiments
765  ME_HEX, ///< hexagon based search
766  ME_UMH, ///< uneven multi-hexagon search
767  ME_TESA, ///< transformed exhaustive search algorithm
768  ME_ITER=50, ///< iterative search
769 };
770 #endif
771 
772 /**
773  * @ingroup lavc_decoding
774  */
776  /* We leave some space between them for extensions (drop some
777  * keyframes for intra-only or drop just some bidir frames). */
778  AVDISCARD_NONE =-16, ///< discard nothing
779  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
780  AVDISCARD_NONREF = 8, ///< discard all non reference
781  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
782  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
783  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
784  AVDISCARD_ALL = 48, ///< discard all
785 };
786 
797  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
798 };
799 
800 /**
801  * @ingroup lavc_encoding
802  */
803 typedef struct RcOverride{
806  int qscale; // If this is 0 then quality_factor will be used instead.
808 } RcOverride;
809 
810 #if FF_API_MAX_BFRAMES
811 /**
812  * @deprecated there is no libavcodec-wide limit on the number of B-frames
813  */
814 #define FF_MAX_B_FRAMES 16
815 #endif
816 
817 /* encoding support
818  These flags can be passed in AVCodecContext.flags before initialization.
819  Note: Not everything is supported yet.
820 */
821 
822 /**
823  * Allow decoders to produce frames with data planes that are not aligned
824  * to CPU requirements (e.g. due to cropping).
825  */
826 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
827 /**
828  * Use fixed qscale.
829  */
830 #define AV_CODEC_FLAG_QSCALE (1 << 1)
831 /**
832  * 4 MV per MB allowed / advanced prediction for H.263.
833  */
834 #define AV_CODEC_FLAG_4MV (1 << 2)
835 /**
836  * Output even those frames that might be corrupted.
837  */
838 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
839 /**
840  * Use qpel MC.
841  */
842 #define AV_CODEC_FLAG_QPEL (1 << 4)
843 /**
844  * Use internal 2pass ratecontrol in first pass mode.
845  */
846 #define AV_CODEC_FLAG_PASS1 (1 << 9)
847 /**
848  * Use internal 2pass ratecontrol in second pass mode.
849  */
850 #define AV_CODEC_FLAG_PASS2 (1 << 10)
851 /**
852  * loop filter.
853  */
854 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
855 /**
856  * Only decode/encode grayscale.
857  */
858 #define AV_CODEC_FLAG_GRAY (1 << 13)
859 /**
860  * error[?] variables will be set during encoding.
861  */
862 #define AV_CODEC_FLAG_PSNR (1 << 15)
863 /**
864  * Input bitstream might be truncated at a random location
865  * instead of only at frame boundaries.
866  */
867 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
868 /**
869  * Use interlaced DCT.
870  */
871 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
872 /**
873  * Force low delay.
874  */
875 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
876 /**
877  * Place global headers in extradata instead of every keyframe.
878  */
879 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
880 /**
881  * Use only bitexact stuff (except (I)DCT).
882  */
883 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
884 /* Fx : Flag for H.263+ extra options */
885 /**
886  * H.263 advanced intra coding / MPEG-4 AC prediction
887  */
888 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
889 /**
890  * interlaced motion estimation
891  */
892 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
893 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
894 
895 /**
896  * Allow non spec compliant speedup tricks.
897  */
898 #define AV_CODEC_FLAG2_FAST (1 << 0)
899 /**
900  * Skip bitstream encoding.
901  */
902 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
903 /**
904  * Place global headers at every keyframe instead of in extradata.
905  */
906 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
907 
908 /**
909  * timecode is in drop frame format. DEPRECATED!!!!
910  */
911 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
912 
913 /**
914  * Input bitstream might be truncated at a packet boundaries
915  * instead of only at frame boundaries.
916  */
917 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
918 /**
919  * Discard cropping information from SPS.
920  */
921 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
922 
923 /**
924  * Show all frames before the first keyframe
925  */
926 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
927 /**
928  * Export motion vectors through frame side data
929  */
930 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
931 /**
932  * Do not skip samples and export skip information as frame side data
933  */
934 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
935 /**
936  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
937  */
938 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
939 
940 /* Unsupported options :
941  * Syntax Arithmetic coding (SAC)
942  * Reference Picture Selection
943  * Independent Segment Decoding */
944 /* /Fx */
945 /* codec capabilities */
946 
947 /**
948  * Decoder can use draw_horiz_band callback.
949  */
950 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
951 /**
952  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
953  * If not set, it might not use get_buffer() at all or use operations that
954  * assume the buffer was allocated by avcodec_default_get_buffer.
955  */
956 #define AV_CODEC_CAP_DR1 (1 << 1)
957 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
958 /**
959  * Encoder or decoder requires flushing with NULL input at the end in order to
960  * give the complete and correct output.
961  *
962  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
963  * with NULL data. The user can still send NULL data to the public encode
964  * or decode function, but libavcodec will not pass it along to the codec
965  * unless this flag is set.
966  *
967  * Decoders:
968  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
969  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
970  * returns frames.
971  *
972  * Encoders:
973  * The encoder needs to be fed with NULL data at the end of encoding until the
974  * encoder no longer returns data.
975  *
976  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
977  * flag also means that the encoder must set the pts and duration for
978  * each output packet. If this flag is not set, the pts and duration will
979  * be determined by libavcodec from the input frame.
980  */
981 #define AV_CODEC_CAP_DELAY (1 << 5)
982 /**
983  * Codec can be fed a final frame with a smaller size.
984  * This can be used to prevent truncation of the last audio samples.
985  */
986 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
987 
988 #if FF_API_CAP_VDPAU
989 /**
990  * Codec can export data for HW decoding (VDPAU).
991  */
992 #define AV_CODEC_CAP_HWACCEL_VDPAU (1 << 7)
993 #endif
994 
995 /**
996  * Codec can output multiple frames per AVPacket
997  * Normally demuxers return one frame at a time, demuxers which do not do
998  * are connected to a parser to split what they return into proper frames.
999  * This flag is reserved to the very rare category of codecs which have a
1000  * bitstream that cannot be split into frames without timeconsuming
1001  * operations like full decoding. Demuxers carrying such bitstreams thus
1002  * may return multiple frames in a packet. This has many disadvantages like
1003  * prohibiting stream copy in many cases thus it should only be considered
1004  * as a last resort.
1005  */
1006 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1007 /**
1008  * Codec is experimental and is thus avoided in favor of non experimental
1009  * encoders
1010  */
1011 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1012 /**
1013  * Codec should fill in channel configuration and samplerate instead of container
1014  */
1015 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1016 /**
1017  * Codec supports frame-level multithreading.
1018  */
1019 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1020 /**
1021  * Codec supports slice-based (or partition-based) multithreading.
1022  */
1023 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1024 /**
1025  * Codec supports changed parameters at any point.
1026  */
1027 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1028 /**
1029  * Codec supports avctx->thread_count == 0 (auto).
1030  */
1031 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1032 /**
1033  * Audio encoder supports receiving a different number of samples in each call.
1034  */
1035 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1036 /**
1037  * Codec is intra only.
1038  */
1039 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1040 /**
1041  * Codec is lossless.
1042  */
1043 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1044 
1045 
1046 #if FF_API_WITHOUT_PREFIX
1047 /**
1048  * Allow decoders to produce frames with data planes that are not aligned
1049  * to CPU requirements (e.g. due to cropping).
1050  */
1051 #define CODEC_FLAG_UNALIGNED AV_CODEC_FLAG_UNALIGNED
1052 #define CODEC_FLAG_QSCALE AV_CODEC_FLAG_QSCALE
1053 #define CODEC_FLAG_4MV AV_CODEC_FLAG_4MV
1054 #define CODEC_FLAG_OUTPUT_CORRUPT AV_CODEC_FLAG_OUTPUT_CORRUPT
1055 #define CODEC_FLAG_QPEL AV_CODEC_FLAG_QPEL
1056 #if FF_API_GMC
1057 /**
1058  * @deprecated use the "gmc" private option of the libxvid encoder
1059  */
1060 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
1061 #endif
1062 #if FF_API_MV0
1063 /**
1064  * @deprecated use the flag "mv0" in the "mpv_flags" private option of the
1065  * mpegvideo encoders
1066  */
1067 #define CODEC_FLAG_MV0 0x0040
1068 #endif
1069 #if FF_API_INPUT_PRESERVED
1070 /**
1071  * @deprecated passing reference-counted frames to the encoders replaces this
1072  * flag
1073  */
1074 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
1075 #endif
1076 #define CODEC_FLAG_PASS1 AV_CODEC_FLAG_PASS1
1077 #define CODEC_FLAG_PASS2 AV_CODEC_FLAG_PASS2
1078 #define CODEC_FLAG_GRAY AV_CODEC_FLAG_GRAY
1079 #if FF_API_EMU_EDGE
1080 /**
1081  * @deprecated edges are not used/required anymore. I.e. this flag is now always
1082  * set.
1083  */
1084 #define CODEC_FLAG_EMU_EDGE 0x4000
1085 #endif
1086 #define CODEC_FLAG_PSNR AV_CODEC_FLAG_PSNR
1087 #define CODEC_FLAG_TRUNCATED AV_CODEC_FLAG_TRUNCATED
1088 
1089 #if FF_API_NORMALIZE_AQP
1090 /**
1091  * @deprecated use the flag "naq" in the "mpv_flags" private option of the
1092  * mpegvideo encoders
1093  */
1094 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000
1095 #endif
1096 #define CODEC_FLAG_INTERLACED_DCT AV_CODEC_FLAG_INTERLACED_DCT
1097 #define CODEC_FLAG_LOW_DELAY AV_CODEC_FLAG_LOW_DELAY
1098 #define CODEC_FLAG_GLOBAL_HEADER AV_CODEC_FLAG_GLOBAL_HEADER
1099 #define CODEC_FLAG_BITEXACT AV_CODEC_FLAG_BITEXACT
1100 #define CODEC_FLAG_AC_PRED AV_CODEC_FLAG_AC_PRED
1101 #define CODEC_FLAG_LOOP_FILTER AV_CODEC_FLAG_LOOP_FILTER
1102 #define CODEC_FLAG_INTERLACED_ME AV_CODEC_FLAG_INTERLACED_ME
1103 #define CODEC_FLAG_CLOSED_GOP AV_CODEC_FLAG_CLOSED_GOP
1104 #define CODEC_FLAG2_FAST AV_CODEC_FLAG2_FAST
1105 #define CODEC_FLAG2_NO_OUTPUT AV_CODEC_FLAG2_NO_OUTPUT
1106 #define CODEC_FLAG2_LOCAL_HEADER AV_CODEC_FLAG2_LOCAL_HEADER
1107 #define CODEC_FLAG2_DROP_FRAME_TIMECODE AV_CODEC_FLAG2_DROP_FRAME_TIMECODE
1108 #define CODEC_FLAG2_IGNORE_CROP AV_CODEC_FLAG2_IGNORE_CROP
1109 
1110 #define CODEC_FLAG2_CHUNKS AV_CODEC_FLAG2_CHUNKS
1111 #define CODEC_FLAG2_SHOW_ALL AV_CODEC_FLAG2_SHOW_ALL
1112 #define CODEC_FLAG2_EXPORT_MVS AV_CODEC_FLAG2_EXPORT_MVS
1113 #define CODEC_FLAG2_SKIP_MANUAL AV_CODEC_FLAG2_SKIP_MANUAL
1114 
1115 /* Unsupported options :
1116  * Syntax Arithmetic coding (SAC)
1117  * Reference Picture Selection
1118  * Independent Segment Decoding */
1119 /* /Fx */
1120 /* codec capabilities */
1121 
1122 #define CODEC_CAP_DRAW_HORIZ_BAND AV_CODEC_CAP_DRAW_HORIZ_BAND ///< Decoder can use draw_horiz_band callback.
1123 /**
1124  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
1125  * If not set, it might not use get_buffer() at all or use operations that
1126  * assume the buffer was allocated by avcodec_default_get_buffer.
1127  */
1128 #define CODEC_CAP_DR1 AV_CODEC_CAP_DR1
1129 #define CODEC_CAP_TRUNCATED AV_CODEC_CAP_TRUNCATED
1130 #if FF_API_XVMC
1131 /* Codec can export data for HW decoding. This flag indicates that
1132  * the codec would call get_format() with list that might contain HW accelerated
1133  * pixel formats (XvMC, VDPAU, VAAPI, etc). The application can pick any of them
1134  * including raw image format.
1135  * The application can use the passed context to determine bitstream version,
1136  * chroma format, resolution etc.
1137  */
1138 #define CODEC_CAP_HWACCEL 0x0010
1139 #endif /* FF_API_XVMC */
1140 /**
1141  * Encoder or decoder requires flushing with NULL input at the end in order to
1142  * give the complete and correct output.
1143  *
1144  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
1145  * with NULL data. The user can still send NULL data to the public encode
1146  * or decode function, but libavcodec will not pass it along to the codec
1147  * unless this flag is set.
1148  *
1149  * Decoders:
1150  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
1151  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
1152  * returns frames.
1153  *
1154  * Encoders:
1155  * The encoder needs to be fed with NULL data at the end of encoding until the
1156  * encoder no longer returns data.
1157  *
1158  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1159  * flag also means that the encoder must set the pts and duration for
1160  * each output packet. If this flag is not set, the pts and duration will
1161  * be determined by libavcodec from the input frame.
1162  */
1163 #define CODEC_CAP_DELAY AV_CODEC_CAP_DELAY
1164 /**
1165  * Codec can be fed a final frame with a smaller size.
1166  * This can be used to prevent truncation of the last audio samples.
1167  */
1168 #define CODEC_CAP_SMALL_LAST_FRAME AV_CODEC_CAP_SMALL_LAST_FRAME
1169 #if FF_API_CAP_VDPAU
1170 /**
1171  * Codec can export data for HW decoding (VDPAU).
1172  */
1173 #define CODEC_CAP_HWACCEL_VDPAU AV_CODEC_CAP_HWACCEL_VDPAU
1174 #endif
1175 /**
1176  * Codec can output multiple frames per AVPacket
1177  * Normally demuxers return one frame at a time, demuxers which do not do
1178  * are connected to a parser to split what they return into proper frames.
1179  * This flag is reserved to the very rare category of codecs which have a
1180  * bitstream that cannot be split into frames without timeconsuming
1181  * operations like full decoding. Demuxers carrying such bitstreams thus
1182  * may return multiple frames in a packet. This has many disadvantages like
1183  * prohibiting stream copy in many cases thus it should only be considered
1184  * as a last resort.
1185  */
1186 #define CODEC_CAP_SUBFRAMES AV_CODEC_CAP_SUBFRAMES
1187 /**
1188  * Codec is experimental and is thus avoided in favor of non experimental
1189  * encoders
1190  */
1191 #define CODEC_CAP_EXPERIMENTAL AV_CODEC_CAP_EXPERIMENTAL
1192 /**
1193  * Codec should fill in channel configuration and samplerate instead of container
1194  */
1195 #define CODEC_CAP_CHANNEL_CONF AV_CODEC_CAP_CHANNEL_CONF
1196 #if FF_API_NEG_LINESIZES
1197 /**
1198  * @deprecated no codecs use this capability
1199  */
1200 #define CODEC_CAP_NEG_LINESIZES 0x0800
1201 #endif
1202 /**
1203  * Codec supports frame-level multithreading.
1204  */
1205 #define CODEC_CAP_FRAME_THREADS AV_CODEC_CAP_FRAME_THREADS
1206 /**
1207  * Codec supports slice-based (or partition-based) multithreading.
1208  */
1209 #define CODEC_CAP_SLICE_THREADS AV_CODEC_CAP_SLICE_THREADS
1210 /**
1211  * Codec supports changed parameters at any point.
1212  */
1213 #define CODEC_CAP_PARAM_CHANGE AV_CODEC_CAP_PARAM_CHANGE
1214 /**
1215  * Codec supports avctx->thread_count == 0 (auto).
1216  */
1217 #define CODEC_CAP_AUTO_THREADS AV_CODEC_CAP_AUTO_THREADS
1218 /**
1219  * Audio encoder supports receiving a different number of samples in each call.
1220  */
1221 #define CODEC_CAP_VARIABLE_FRAME_SIZE AV_CODEC_CAP_VARIABLE_FRAME_SIZE
1222 /**
1223  * Codec is intra only.
1224  */
1225 #define CODEC_CAP_INTRA_ONLY AV_CODEC_CAP_INTRA_ONLY
1226 /**
1227  * Codec is lossless.
1228  */
1229 #define CODEC_CAP_LOSSLESS AV_CODEC_CAP_LOSSLESS
1230 
1231 /**
1232  * HWAccel is experimental and is thus avoided in favor of non experimental
1233  * codecs
1234  */
1235 #define HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
1236 #endif /* FF_API_WITHOUT_PREFIX */
1237 
1238 #if FF_API_MB_TYPE
1239 //The following defines may change, don't expect compatibility if you use them.
1240 #define MB_TYPE_INTRA4x4 0x0001
1241 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
1242 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
1243 #define MB_TYPE_16x16 0x0008
1244 #define MB_TYPE_16x8 0x0010
1245 #define MB_TYPE_8x16 0x0020
1246 #define MB_TYPE_8x8 0x0040
1247 #define MB_TYPE_INTERLACED 0x0080
1248 #define MB_TYPE_DIRECT2 0x0100 //FIXME
1249 #define MB_TYPE_ACPRED 0x0200
1250 #define MB_TYPE_GMC 0x0400
1251 #define MB_TYPE_SKIP 0x0800
1252 #define MB_TYPE_P0L0 0x1000
1253 #define MB_TYPE_P1L0 0x2000
1254 #define MB_TYPE_P0L1 0x4000
1255 #define MB_TYPE_P1L1 0x8000
1256 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
1257 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
1258 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
1259 #define MB_TYPE_QUANT 0x00010000
1260 #define MB_TYPE_CBP 0x00020000
1261 // Note bits 24-31 are reserved for codec specific use (H.264 ref0, MPEG-1 0mv, ...)
1262 #endif
1263 
1264 /**
1265  * Pan Scan area.
1266  * This specifies the area which should be displayed.
1267  * Note there may be multiple such areas for one frame.
1268  */
1269 typedef struct AVPanScan{
1270  /**
1271  * id
1272  * - encoding: Set by user.
1273  * - decoding: Set by libavcodec.
1274  */
1275  int id;
1276 
1277  /**
1278  * width and height in 1/16 pel
1279  * - encoding: Set by user.
1280  * - decoding: Set by libavcodec.
1281  */
1282  int width;
1283  int height;
1284 
1285  /**
1286  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1287  * - encoding: Set by user.
1288  * - decoding: Set by libavcodec.
1289  */
1290  int16_t position[3][2];
1291 }AVPanScan;
1292 
1293 /**
1294  * This structure describes the bitrate properties of an encoded bitstream. It
1295  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1296  * parameters for H.264/HEVC.
1297  */
1298 typedef struct AVCPBProperties {
1299  /**
1300  * Maximum bitrate of the stream, in bits per second.
1301  * Zero if unknown or unspecified.
1302  */
1304  /**
1305  * Minimum bitrate of the stream, in bits per second.
1306  * Zero if unknown or unspecified.
1307  */
1309  /**
1310  * Average bitrate of the stream, in bits per second.
1311  * Zero if unknown or unspecified.
1312  */
1314 
1315  /**
1316  * The size of the buffer to which the ratecontrol is applied, in bits.
1317  * Zero if unknown or unspecified.
1318  */
1320 
1321  /**
1322  * The delay between the time the packet this structure is associated with
1323  * is received and the time when it should be decoded, in periods of a 27MHz
1324  * clock.
1325  *
1326  * UINT64_MAX when unknown or unspecified.
1327  */
1328  uint64_t vbv_delay;
1329 } AVCPBProperties;
1330 
1331 #if FF_API_QSCALE_TYPE
1332 #define FF_QSCALE_TYPE_MPEG1 0
1333 #define FF_QSCALE_TYPE_MPEG2 1
1334 #define FF_QSCALE_TYPE_H264 2
1335 #define FF_QSCALE_TYPE_VP56 3
1336 #endif
1337 
1338 /**
1339  * The decoder will keep a reference to the frame and may reuse it later.
1340  */
1341 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1342 
1343 /**
1344  * @defgroup lavc_packet AVPacket
1345  *
1346  * Types and functions for working with AVPacket.
1347  * @{
1348  */
1352 
1353  /**
1354  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1355  * @code
1356  * u32le param_flags
1357  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1358  * s32le channel_count
1359  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1360  * u64le channel_layout
1361  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1362  * s32le sample_rate
1363  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1364  * s32le width
1365  * s32le height
1366  * @endcode
1367  */
1369 
1370  /**
1371  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1372  * structures with info about macroblocks relevant to splitting the
1373  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1374  * That is, it does not necessarily contain info about all macroblocks,
1375  * as long as the distance between macroblocks in the info is smaller
1376  * than the target payload size.
1377  * Each MB info structure is 12 bytes, and is laid out as follows:
1378  * @code
1379  * u32le bit offset from the start of the packet
1380  * u8 current quantizer at the start of the macroblock
1381  * u8 GOB number
1382  * u16le macroblock address within the GOB
1383  * u8 horizontal MV predictor
1384  * u8 vertical MV predictor
1385  * u8 horizontal MV predictor for block number 3
1386  * u8 vertical MV predictor for block number 3
1387  * @endcode
1388  */
1390 
1391  /**
1392  * This side data should be associated with an audio stream and contains
1393  * ReplayGain information in form of the AVReplayGain struct.
1394  */
1396 
1397  /**
1398  * This side data contains a 3x3 transformation matrix describing an affine
1399  * transformation that needs to be applied to the decoded video frames for
1400  * correct presentation.
1401  *
1402  * See libavutil/display.h for a detailed description of the data.
1403  */
1405 
1406  /**
1407  * This side data should be associated with a video stream and contains
1408  * Stereoscopic 3D information in form of the AVStereo3D struct.
1409  */
1411 
1412  /**
1413  * This side data should be associated with an audio stream and corresponds
1414  * to enum AVAudioServiceType.
1415  */
1417 
1418  /**
1419  * This side data contains quality related information from the encoder.
1420  * @code
1421  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1422  * u8 picture type
1423  * u8 error count
1424  * u16 reserved
1425  * u64le[error count] sum of squared differences between encoder in and output
1426  * @endcode
1427  */
1429 
1430  /**
1431  * This side data contains an integer value representing the stream index
1432  * of a "fallback" track. A fallback track indicates an alternate
1433  * track to use when the current track can not be decoded for some reason.
1434  * e.g. no decoder available for codec.
1435  */
1437 
1438  /**
1439  * This side data corresponds to the AVCPBProperties struct.
1440  */
1442 
1443  /**
1444  * Recommmends skipping the specified number of samples
1445  * @code
1446  * u32le number of samples to skip from start of this packet
1447  * u32le number of samples to skip from end of this packet
1448  * u8 reason for start skip
1449  * u8 reason for end skip (0=padding silence, 1=convergence)
1450  * @endcode
1451  */
1453 
1454  /**
1455  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1456  * the packet may contain "dual mono" audio specific to Japanese DTV
1457  * and if it is true, recommends only the selected channel to be used.
1458  * @code
1459  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1460  * @endcode
1461  */
1463 
1464  /**
1465  * A list of zero terminated key/value strings. There is no end marker for
1466  * the list, so it is required to rely on the side data size to stop.
1467  */
1469 
1470  /**
1471  * Subtitle event position
1472  * @code
1473  * u32le x1
1474  * u32le y1
1475  * u32le x2
1476  * u32le y2
1477  * @endcode
1478  */
1480 
1481  /**
1482  * Data found in BlockAdditional element of matroska container. There is
1483  * no end marker for the data, so it is required to rely on the side data
1484  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1485  * by data.
1486  */
1488 
1489  /**
1490  * The optional first identifier line of a WebVTT cue.
1491  */
1493 
1494  /**
1495  * The optional settings (rendering instructions) that immediately
1496  * follow the timestamp specifier of a WebVTT cue.
1497  */
1499 
1500  /**
1501  * A list of zero terminated key/value strings. There is no end marker for
1502  * the list, so it is required to rely on the side data size to stop. This
1503  * side data includes updated metadata which appeared in the stream.
1504  */
1506 
1507  /**
1508  * MPEGTS stream ID, this is required to pass the stream ID
1509  * information from the demuxer to the corresponding muxer.
1510  */
1512 
1513  /**
1514  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1515  * should be associated with a video stream and containts data in the form
1516  * of the AVMasteringDisplayMetadata struct.
1517  */
1519 };
1520 
1521 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1522 
1523 typedef struct AVPacketSideData {
1525  int size;
1528 
1529 /**
1530  * This structure stores compressed data. It is typically exported by demuxers
1531  * and then passed as input to decoders, or received as output from encoders and
1532  * then passed to muxers.
1533  *
1534  * For video, it should typically contain one compressed frame. For audio it may
1535  * contain several compressed frames. Encoders are allowed to output empty
1536  * packets, with no compressed data, containing only side data
1537  * (e.g. to update some stream parameters at the end of encoding).
1538  *
1539  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1540  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1541  * without libavcodec and libavformat major bump.
1542  *
1543  * The semantics of data ownership depends on the buf field.
1544  * If it is set, the packet data is dynamically allocated and is
1545  * valid indefinitely until a call to av_packet_unref() reduces the
1546  * reference count to 0.
1547  *
1548  * If the buf field is not set av_packet_ref() would make a copy instead
1549  * of increasing the reference count.
1550  *
1551  * The side data is always allocated with av_malloc(), copied by
1552  * av_packet_ref() and freed by av_packet_unref().
1553  *
1554  * @see av_packet_ref
1555  * @see av_packet_unref
1556  */
1557 typedef struct AVPacket {
1558  /**
1559  * A reference to the reference-counted buffer where the packet data is
1560  * stored.
1561  * May be NULL, then the packet data is not reference-counted.
1562  */
1564  /**
1565  * Presentation timestamp in AVStream->time_base units; the time at which
1566  * the decompressed packet will be presented to the user.
1567  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1568  * pts MUST be larger or equal to dts as presentation cannot happen before
1569  * decompression, unless one wants to view hex dumps. Some formats misuse
1570  * the terms dts and pts/cts to mean something different. Such timestamps
1571  * must be converted to true pts/dts before they are stored in AVPacket.
1572  */
1573  int64_t pts;
1574  /**
1575  * Decompression timestamp in AVStream->time_base units; the time at which
1576  * the packet is decompressed.
1577  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1578  */
1579  int64_t dts;
1581  int size;
1583  /**
1584  * A combination of AV_PKT_FLAG values
1585  */
1586  int flags;
1587  /**
1588  * Additional packet data that can be provided by the container.
1589  * Packet can contain several types of side information.
1590  */
1593 
1594  /**
1595  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1596  * Equals next_pts - this_pts in presentation order.
1597  */
1598  int64_t duration;
1599 
1600  int64_t pos; ///< byte position in stream, -1 if unknown
1601 
1602 #if FF_API_CONVERGENCE_DURATION
1603  /**
1604  * @deprecated Same as the duration field, but as int64_t. This was required
1605  * for Matroska subtitles, whose duration values could overflow when the
1606  * duration field was still an int.
1607  */
1610 #endif
1611 } AVPacket;
1612 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1613 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1614 
1620 };
1621 /**
1622  * @}
1623  */
1624 
1625 struct AVCodecInternal;
1626 
1630  AV_FIELD_TT, //< Top coded_first, top displayed first
1631  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1632  AV_FIELD_TB, //< Top coded first, bottom displayed first
1633  AV_FIELD_BT, //< Bottom coded first, top displayed first
1634 };
1635 
1636 /**
1637  * main external API structure.
1638  * New fields can be added to the end with minor version bumps.
1639  * Removal, reordering and changes to existing fields require a major
1640  * version bump.
1641  * Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1642  * applications.
1643  * The name string for AVOptions options matches the associated command line
1644  * parameter name and can be found in libavcodec/options_table.h
1645  * The AVOption/command line parameter names differ in some cases from the C
1646  * structure field names for historic reasons or brevity.
1647  * sizeof(AVCodecContext) must not be used outside libav*.
1648  */
1649 typedef struct AVCodecContext {
1650  /**
1651  * information on struct for av_log
1652  * - set by avcodec_alloc_context3
1653  */
1656 
1657  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1658  const struct AVCodec *codec;
1659 #if FF_API_CODEC_NAME
1660  /**
1661  * @deprecated this field is not used for anything in libavcodec
1662  */
1664  char codec_name[32];
1665 #endif
1666  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1667 
1668  /**
1669  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1670  * This is used to work around some encoder bugs.
1671  * A demuxer should set this to what is stored in the field used to identify the codec.
1672  * If there are multiple such fields in a container then the demuxer should choose the one
1673  * which maximizes the information about the used codec.
1674  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1675  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1676  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1677  * first.
1678  * - encoding: Set by user, if not then the default based on codec_id will be used.
1679  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1680  */
1681  unsigned int codec_tag;
1682 
1683 #if FF_API_STREAM_CODEC_TAG
1684  /**
1685  * @deprecated this field is unused
1686  */
1688  unsigned int stream_codec_tag;
1689 #endif
1690 
1691  void *priv_data;
1692 
1693  /**
1694  * Private context used for internal data.
1695  *
1696  * Unlike priv_data, this is not codec-specific. It is used in general
1697  * libavcodec functions.
1698  */
1699  struct AVCodecInternal *internal;
1700 
1701  /**
1702  * Private data of the user, can be used to carry app specific stuff.
1703  * - encoding: Set by user.
1704  * - decoding: Set by user.
1705  */
1706  void *opaque;
1707 
1708  /**
1709  * the average bitrate
1710  * - encoding: Set by user; unused for constant quantizer encoding.
1711  * - decoding: Set by user, may be overwritten by libavcodec
1712  * if this info is available in the stream
1713  */
1714  int64_t bit_rate;
1715 
1716  /**
1717  * number of bits the bitstream is allowed to diverge from the reference.
1718  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1719  * - encoding: Set by user; unused for constant quantizer encoding.
1720  * - decoding: unused
1721  */
1723 
1724  /**
1725  * Global quality for codecs which cannot change it per frame.
1726  * This should be proportional to MPEG-1/2/4 qscale.
1727  * - encoding: Set by user.
1728  * - decoding: unused
1729  */
1731 
1732  /**
1733  * - encoding: Set by user.
1734  * - decoding: unused
1735  */
1737 #define FF_COMPRESSION_DEFAULT -1
1738 
1739  /**
1740  * AV_CODEC_FLAG_*.
1741  * - encoding: Set by user.
1742  * - decoding: Set by user.
1743  */
1744  int flags;
1745 
1746  /**
1747  * AV_CODEC_FLAG2_*
1748  * - encoding: Set by user.
1749  * - decoding: Set by user.
1750  */
1751  int flags2;
1752 
1753  /**
1754  * some codecs need / can use extradata like Huffman tables.
1755  * MJPEG: Huffman tables
1756  * rv10: additional flags
1757  * MPEG-4: global headers (they can be in the bitstream or here)
1758  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1759  * than extradata_size to avoid problems if it is read with the bitstream reader.
1760  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1761  * - encoding: Set/allocated/freed by libavcodec.
1762  * - decoding: Set/allocated/freed by user.
1763  */
1766 
1767  /**
1768  * This is the fundamental unit of time (in seconds) in terms
1769  * of which frame timestamps are represented. For fixed-fps content,
1770  * timebase should be 1/framerate and timestamp increments should be
1771  * identically 1.
1772  * This often, but not always is the inverse of the frame rate or field rate
1773  * for video. 1/time_base is not the average frame rate if the frame rate is not
1774  * constant.
1775  *
1776  * Like containers, elementary streams also can store timestamps, 1/time_base
1777  * is the unit in which these timestamps are specified.
1778  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1779  * vop_time_increment_resolution and fixed_vop_rate
1780  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1781  *
1782  * - encoding: MUST be set by user.
1783  * - decoding: the use of this field for decoding is deprecated.
1784  * Use framerate instead.
1785  */
1787 
1788  /**
1789  * For some codecs, the time base is closer to the field rate than the frame rate.
1790  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1791  * if no telecine is used ...
1792  *
1793  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1794  */
1796 
1797  /**
1798  * Codec delay.
1799  *
1800  * Encoding: Number of frames delay there will be from the encoder input to
1801  * the decoder output. (we assume the decoder matches the spec)
1802  * Decoding: Number of frames delay in addition to what a standard decoder
1803  * as specified in the spec would produce.
1804  *
1805  * Video:
1806  * Number of frames the decoded output will be delayed relative to the
1807  * encoded input.
1808  *
1809  * Audio:
1810  * For encoding, this field is unused (see initial_padding).
1811  *
1812  * For decoding, this is the number of samples the decoder needs to
1813  * output before the decoder's output is valid. When seeking, you should
1814  * start decoding this many samples prior to your desired seek point.
1815  *
1816  * - encoding: Set by libavcodec.
1817  * - decoding: Set by libavcodec.
1818  */
1819  int delay;
1820 
1821 
1822  /* video only */
1823  /**
1824  * picture width / height.
1825  *
1826  * @note Those fields may not match the values of the last
1827  * AVFrame output by avcodec_decode_video2 due frame
1828  * reordering.
1829  *
1830  * - encoding: MUST be set by user.
1831  * - decoding: May be set by the user before opening the decoder if known e.g.
1832  * from the container. Some decoders will require the dimensions
1833  * to be set by the caller. During decoding, the decoder may
1834  * overwrite those values as required while parsing the data.
1835  */
1837 
1838  /**
1839  * Bitstream width / height, may be different from width/height e.g. when
1840  * the decoded frame is cropped before being output or lowres is enabled.
1841  *
1842  * @note Those field may not match the value of the last
1843  * AVFrame output by avcodec_receive_frame() due frame
1844  * reordering.
1845  *
1846  * - encoding: unused
1847  * - decoding: May be set by the user before opening the decoder if known
1848  * e.g. from the container. During decoding, the decoder may
1849  * overwrite those values as required while parsing the data.
1850  */
1852 
1853 #if FF_API_ASPECT_EXTENDED
1854 #define FF_ASPECT_EXTENDED 15
1855 #endif
1856 
1857  /**
1858  * the number of pictures in a group of pictures, or 0 for intra_only
1859  * - encoding: Set by user.
1860  * - decoding: unused
1861  */
1863 
1864  /**
1865  * Pixel format, see AV_PIX_FMT_xxx.
1866  * May be set by the demuxer if known from headers.
1867  * May be overridden by the decoder if it knows better.
1868  *
1869  * @note This field may not match the value of the last
1870  * AVFrame output by avcodec_receive_frame() due frame
1871  * reordering.
1872  *
1873  * - encoding: Set by user.
1874  * - decoding: Set by user if known, overridden by libavcodec while
1875  * parsing the data.
1876  */
1878 
1879 #if FF_API_MOTION_EST
1880  /**
1881  * This option does nothing
1882  * @deprecated use codec private options instead
1883  */
1885 #endif
1886 
1887  /**
1888  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1889  * decoder to draw a horizontal band. It improves cache usage. Not
1890  * all codecs can do that. You must check the codec capabilities
1891  * beforehand.
1892  * When multithreading is used, it may be called from multiple threads
1893  * at the same time; threads might draw different parts of the same AVFrame,
1894  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1895  * in order.
1896  * The function is also used by hardware acceleration APIs.
1897  * It is called at least once during frame decoding to pass
1898  * the data needed for hardware render.
1899  * In that mode instead of pixel data, AVFrame points to
1900  * a structure specific to the acceleration API. The application
1901  * reads the structure and can change some fields to indicate progress
1902  * or mark state.
1903  * - encoding: unused
1904  * - decoding: Set by user.
1905  * @param height the height of the slice
1906  * @param y the y position of the slice
1907  * @param type 1->top field, 2->bottom field, 3->frame
1908  * @param offset offset into the AVFrame.data from which the slice should be read
1909  */
1911  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1912  int y, int type, int height);
1913 
1914  /**
1915  * callback to negotiate the pixelFormat
1916  * @param fmt is the list of formats which are supported by the codec,
1917  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1918  * The first is always the native one.
1919  * @note The callback may be called again immediately if initialization for
1920  * the selected (hardware-accelerated) pixel format failed.
1921  * @warning Behavior is undefined if the callback returns a value not
1922  * in the fmt list of formats.
1923  * @return the chosen format
1924  * - encoding: unused
1925  * - decoding: Set by user, if not set the native format will be chosen.
1926  */
1927  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1928 
1929  /**
1930  * maximum number of B-frames between non-B-frames
1931  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1932  * - encoding: Set by user.
1933  * - decoding: unused
1934  */
1936 
1937  /**
1938  * qscale factor between IP and B-frames
1939  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1940  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1941  * - encoding: Set by user.
1942  * - decoding: unused
1943  */
1945 
1946 #if FF_API_RC_STRATEGY
1947  /** @deprecated use codec private option instead */
1949 #define FF_RC_STRATEGY_XVID 1
1950 #endif
1951 
1952 #if FF_API_PRIVATE_OPT
1953  /** @deprecated use encoder private options instead */
1956 #endif
1957 
1958  /**
1959  * qscale offset between IP and B-frames
1960  * - encoding: Set by user.
1961  * - decoding: unused
1962  */
1964 
1965  /**
1966  * Size of the frame reordering buffer in the decoder.
1967  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1968  * - encoding: Set by libavcodec.
1969  * - decoding: Set by libavcodec.
1970  */
1972 
1973 #if FF_API_PRIVATE_OPT
1974  /** @deprecated use encoder private options instead */
1977 #endif
1978 
1979  /**
1980  * qscale factor between P- and I-frames
1981  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1982  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1983  * - encoding: Set by user.
1984  * - decoding: unused
1985  */
1987 
1988  /**
1989  * qscale offset between P and I-frames
1990  * - encoding: Set by user.
1991  * - decoding: unused
1992  */
1994 
1995  /**
1996  * luminance masking (0-> disabled)
1997  * - encoding: Set by user.
1998  * - decoding: unused
1999  */
2001 
2002  /**
2003  * temporary complexity masking (0-> disabled)
2004  * - encoding: Set by user.
2005  * - decoding: unused
2006  */
2008 
2009  /**
2010  * spatial complexity masking (0-> disabled)
2011  * - encoding: Set by user.
2012  * - decoding: unused
2013  */
2015 
2016  /**
2017  * p block masking (0-> disabled)
2018  * - encoding: Set by user.
2019  * - decoding: unused
2020  */
2021  float p_masking;
2022 
2023  /**
2024  * darkness masking (0-> disabled)
2025  * - encoding: Set by user.
2026  * - decoding: unused
2027  */
2029 
2030  /**
2031  * slice count
2032  * - encoding: Set by libavcodec.
2033  * - decoding: Set by user (or 0).
2034  */
2036 
2037 #if FF_API_PRIVATE_OPT
2038  /** @deprecated use encoder private options instead */
2041 #define FF_PRED_LEFT 0
2042 #define FF_PRED_PLANE 1
2043 #define FF_PRED_MEDIAN 2
2044 #endif
2045 
2046  /**
2047  * slice offsets in the frame in bytes
2048  * - encoding: Set/allocated by libavcodec.
2049  * - decoding: Set/allocated by user (or NULL).
2050  */
2052 
2053  /**
2054  * sample aspect ratio (0 if unknown)
2055  * That is the width of a pixel divided by the height of the pixel.
2056  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
2057  * - encoding: Set by user.
2058  * - decoding: Set by libavcodec.
2059  */
2061 
2062  /**
2063  * motion estimation comparison function
2064  * - encoding: Set by user.
2065  * - decoding: unused
2066  */
2067  int me_cmp;
2068  /**
2069  * subpixel motion estimation comparison function
2070  * - encoding: Set by user.
2071  * - decoding: unused
2072  */
2074  /**
2075  * macroblock comparison function (not supported yet)
2076  * - encoding: Set by user.
2077  * - decoding: unused
2078  */
2079  int mb_cmp;
2080  /**
2081  * interlaced DCT comparison function
2082  * - encoding: Set by user.
2083  * - decoding: unused
2084  */
2086 #define FF_CMP_SAD 0
2087 #define FF_CMP_SSE 1
2088 #define FF_CMP_SATD 2
2089 #define FF_CMP_DCT 3
2090 #define FF_CMP_PSNR 4
2091 #define FF_CMP_BIT 5
2092 #define FF_CMP_RD 6
2093 #define FF_CMP_ZERO 7
2094 #define FF_CMP_VSAD 8
2095 #define FF_CMP_VSSE 9
2096 #define FF_CMP_NSSE 10
2097 #define FF_CMP_W53 11
2098 #define FF_CMP_W97 12
2099 #define FF_CMP_DCTMAX 13
2100 #define FF_CMP_DCT264 14
2101 #define FF_CMP_CHROMA 256
2102 
2103  /**
2104  * ME diamond size & shape
2105  * - encoding: Set by user.
2106  * - decoding: unused
2107  */
2109 
2110  /**
2111  * amount of previous MV predictors (2a+1 x 2a+1 square)
2112  * - encoding: Set by user.
2113  * - decoding: unused
2114  */
2116 
2117 #if FF_API_PRIVATE_OPT
2118  /** @deprecated use encoder private options instead */
2120  int pre_me;
2121 #endif
2122 
2123  /**
2124  * motion estimation prepass comparison function
2125  * - encoding: Set by user.
2126  * - decoding: unused
2127  */
2129 
2130  /**
2131  * ME prepass diamond size & shape
2132  * - encoding: Set by user.
2133  * - decoding: unused
2134  */
2136 
2137  /**
2138  * subpel ME quality
2139  * - encoding: Set by user.
2140  * - decoding: unused
2141  */
2143 
2144 #if FF_API_AFD
2145  /**
2146  * DTG active format information (additional aspect ratio
2147  * information only used in DVB MPEG-2 transport streams)
2148  * 0 if not set.
2149  *
2150  * - encoding: unused
2151  * - decoding: Set by decoder.
2152  * @deprecated Deprecated in favor of AVSideData
2153  */
2155 #define FF_DTG_AFD_SAME 8
2156 #define FF_DTG_AFD_4_3 9
2157 #define FF_DTG_AFD_16_9 10
2158 #define FF_DTG_AFD_14_9 11
2159 #define FF_DTG_AFD_4_3_SP_14_9 13
2160 #define FF_DTG_AFD_16_9_SP_14_9 14
2161 #define FF_DTG_AFD_SP_4_3 15
2162 #endif /* FF_API_AFD */
2163 
2164  /**
2165  * maximum motion estimation search range in subpel units
2166  * If 0 then no limit.
2167  *
2168  * - encoding: Set by user.
2169  * - decoding: unused
2170  */
2172 
2173 #if FF_API_QUANT_BIAS
2174  /**
2175  * @deprecated use encoder private option instead
2176  */
2178 #define FF_DEFAULT_QUANT_BIAS 999999
2179 
2180  /**
2181  * @deprecated use encoder private option instead
2182  */
2184 #endif
2185 
2186  /**
2187  * slice flags
2188  * - encoding: unused
2189  * - decoding: Set by user.
2190  */
2192 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2193 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2194 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2195 
2196 #if FF_API_XVMC
2197  /**
2198  * XVideo Motion Acceleration
2199  * - encoding: forbidden
2200  * - decoding: set by decoder
2201  * @deprecated XvMC doesn't need it anymore.
2202  */
2203  attribute_deprecated int xvmc_acceleration;
2204 #endif /* FF_API_XVMC */
2205 
2206  /**
2207  * macroblock decision mode
2208  * - encoding: Set by user.
2209  * - decoding: unused
2210  */
2212 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2213 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2214 #define FF_MB_DECISION_RD 2 ///< rate distortion
2215 
2216  /**
2217  * custom intra quantization matrix
2218  * - encoding: Set by user, can be NULL.
2219  * - decoding: Set by libavcodec.
2220  */
2221  uint16_t *intra_matrix;
2222 
2223  /**
2224  * custom inter quantization matrix
2225  * - encoding: Set by user, can be NULL.
2226  * - decoding: Set by libavcodec.
2227  */
2228  uint16_t *inter_matrix;
2229 
2230 #if FF_API_PRIVATE_OPT
2231  /** @deprecated use encoder private options instead */
2234 
2235  /** @deprecated use encoder private options instead */
2238 #endif
2239 
2240 #if FF_API_MPV_OPT
2241  /**
2242  * @deprecated this field is unused
2243  */
2246 
2247  /**
2248  * @deprecated this field is unused
2249  */
2252 #endif
2253 
2254  /**
2255  * precision of the intra DC coefficient - 8
2256  * - encoding: Set by user.
2257  * - decoding: Set by libavcodec
2258  */
2260 
2261  /**
2262  * Number of macroblock rows at the top which are skipped.
2263  * - encoding: unused
2264  * - decoding: Set by user.
2265  */
2267 
2268  /**
2269  * Number of macroblock rows at the bottom which are skipped.
2270  * - encoding: unused
2271  * - decoding: Set by user.
2272  */
2274 
2275 #if FF_API_MPV_OPT
2276  /**
2277  * @deprecated use encoder private options instead
2278  */
2281 #endif
2282 
2283  /**
2284  * minimum MB Lagrange multiplier
2285  * - encoding: Set by user.
2286  * - decoding: unused
2287  */
2288  int mb_lmin;
2289 
2290  /**
2291  * maximum MB Lagrange multiplier
2292  * - encoding: Set by user.
2293  * - decoding: unused
2294  */
2295  int mb_lmax;
2296 
2297 #if FF_API_PRIVATE_OPT
2298  /**
2299  * @deprecated use encoder private options instead
2300  */
2303 #endif
2304 
2305  /**
2306  * - encoding: Set by user.
2307  * - decoding: unused
2308  */
2310 
2311 #if FF_API_PRIVATE_OPT
2312  /** @deprecated use encoder private options instead */
2315 #endif
2316 
2317  /**
2318  * minimum GOP size
2319  * - encoding: Set by user.
2320  * - decoding: unused
2321  */
2323 
2324  /**
2325  * number of reference frames
2326  * - encoding: Set by user.
2327  * - decoding: Set by lavc.
2328  */
2329  int refs;
2330 
2331 #if FF_API_PRIVATE_OPT
2332  /** @deprecated use encoder private options instead */
2335 #endif
2336 
2337 #if FF_API_UNUSED_MEMBERS
2338  /**
2339  * Multiplied by qscale for each frame and added to scene_change_score.
2340  * - encoding: Set by user.
2341  * - decoding: unused
2342  */
2344 #endif
2345 
2346  /**
2347  * Note: Value depends upon the compare function used for fullpel ME.
2348  * - encoding: Set by user.
2349  * - decoding: unused
2350  */
2352 
2353 #if FF_API_PRIVATE_OPT
2354  /** @deprecated use encoder private options instead */
2357 #endif
2358 
2359  /**
2360  * Chromaticity coordinates of the source primaries.
2361  * - encoding: Set by user
2362  * - decoding: Set by libavcodec
2363  */
2365 
2366  /**
2367  * Color Transfer Characteristic.
2368  * - encoding: Set by user
2369  * - decoding: Set by libavcodec
2370  */
2372 
2373  /**
2374  * YUV colorspace type.
2375  * - encoding: Set by user
2376  * - decoding: Set by libavcodec
2377  */
2379 
2380  /**
2381  * MPEG vs JPEG YUV range.
2382  * - encoding: Set by user
2383  * - decoding: Set by libavcodec
2384  */
2386 
2387  /**
2388  * This defines the location of chroma samples.
2389  * - encoding: Set by user
2390  * - decoding: Set by libavcodec
2391  */
2393 
2394  /**
2395  * Number of slices.
2396  * Indicates number of picture subdivisions. Used for parallelized
2397  * decoding.
2398  * - encoding: Set by user
2399  * - decoding: unused
2400  */
2401  int slices;
2402 
2403  /** Field order
2404  * - encoding: set by libavcodec
2405  * - decoding: Set by user.
2406  */
2408 
2409  /* audio only */
2410  int sample_rate; ///< samples per second
2411  int channels; ///< number of audio channels
2412 
2413  /**
2414  * audio sample format
2415  * - encoding: Set by user.
2416  * - decoding: Set by libavcodec.
2417  */
2418  enum AVSampleFormat sample_fmt; ///< sample format
2419 
2420  /* The following data should not be initialized. */
2421  /**
2422  * Number of samples per channel in an audio frame.
2423  *
2424  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2425  * except the last must contain exactly frame_size samples per channel.
2426  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2427  * frame size is not restricted.
2428  * - decoding: may be set by some decoders to indicate constant frame size
2429  */
2431 
2432  /**
2433  * Frame counter, set by libavcodec.
2434  *
2435  * - decoding: total number of frames returned from the decoder so far.
2436  * - encoding: total number of frames passed to the encoder so far.
2437  *
2438  * @note the counter is not incremented if encoding/decoding resulted in
2439  * an error.
2440  */
2442 
2443  /**
2444  * number of bytes per packet if constant and known or 0
2445  * Used by some WAV based audio codecs.
2446  */
2448 
2449  /**
2450  * Audio cutoff bandwidth (0 means "automatic")
2451  * - encoding: Set by user.
2452  * - decoding: unused
2453  */
2454  int cutoff;
2455 
2456  /**
2457  * Audio channel layout.
2458  * - encoding: set by user.
2459  * - decoding: set by user, may be overwritten by libavcodec.
2460  */
2461  uint64_t channel_layout;
2462 
2463  /**
2464  * Request decoder to use this channel layout if it can (0 for default)
2465  * - encoding: unused
2466  * - decoding: Set by user.
2467  */
2469 
2470  /**
2471  * Type of service that the audio stream conveys.
2472  * - encoding: Set by user.
2473  * - decoding: Set by libavcodec.
2474  */
2476 
2477  /**
2478  * desired sample format
2479  * - encoding: Not used.
2480  * - decoding: Set by user.
2481  * Decoder will decode to this format if it can.
2482  */
2484 
2485  /**
2486  * This callback is called at the beginning of each frame to get data
2487  * buffer(s) for it. There may be one contiguous buffer for all the data or
2488  * there may be a buffer per each data plane or anything in between. What
2489  * this means is, you may set however many entries in buf[] you feel necessary.
2490  * Each buffer must be reference-counted using the AVBuffer API (see description
2491  * of buf[] below).
2492  *
2493  * The following fields will be set in the frame before this callback is
2494  * called:
2495  * - format
2496  * - width, height (video only)
2497  * - sample_rate, channel_layout, nb_samples (audio only)
2498  * Their values may differ from the corresponding values in
2499  * AVCodecContext. This callback must use the frame values, not the codec
2500  * context values, to calculate the required buffer size.
2501  *
2502  * This callback must fill the following fields in the frame:
2503  * - data[]
2504  * - linesize[]
2505  * - extended_data:
2506  * * if the data is planar audio with more than 8 channels, then this
2507  * callback must allocate and fill extended_data to contain all pointers
2508  * to all data planes. data[] must hold as many pointers as it can.
2509  * extended_data must be allocated with av_malloc() and will be freed in
2510  * av_frame_unref().
2511  * * otherwise extended_data must point to data
2512  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2513  * the frame's data and extended_data pointers must be contained in these. That
2514  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2515  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2516  * and av_buffer_ref().
2517  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2518  * this callback and filled with the extra buffers if there are more
2519  * buffers than buf[] can hold. extended_buf will be freed in
2520  * av_frame_unref().
2521  *
2522  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2523  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2524  * some other means.
2525  *
2526  * Each data plane must be aligned to the maximum required by the target
2527  * CPU.
2528  *
2529  * @see avcodec_default_get_buffer2()
2530  *
2531  * Video:
2532  *
2533  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2534  * (read and/or written to if it is writable) later by libavcodec.
2535  *
2536  * avcodec_align_dimensions2() should be used to find the required width and
2537  * height, as they normally need to be rounded up to the next multiple of 16.
2538  *
2539  * Some decoders do not support linesizes changing between frames.
2540  *
2541  * If frame multithreading is used and thread_safe_callbacks is set,
2542  * this callback may be called from a different thread, but not from more
2543  * than one at once. Does not need to be reentrant.
2544  *
2545  * @see avcodec_align_dimensions2()
2546  *
2547  * Audio:
2548  *
2549  * Decoders request a buffer of a particular size by setting
2550  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2551  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2552  * to a smaller value in the output frame.
2553  *
2554  * As a convenience, av_samples_get_buffer_size() and
2555  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2556  * functions to find the required data size and to fill data pointers and
2557  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2558  * since all planes must be the same size.
2559  *
2560  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2561  *
2562  * - encoding: unused
2563  * - decoding: Set by libavcodec, user can override.
2564  */
2565  int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2566 
2567  /**
2568  * If non-zero, the decoded audio and video frames returned from
2569  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2570  * and are valid indefinitely. The caller must free them with
2571  * av_frame_unref() when they are not needed anymore.
2572  * Otherwise, the decoded frames must not be freed by the caller and are
2573  * only valid until the next decode call.
2574  *
2575  * This is always automatically enabled if avcodec_receive_frame() is used.
2576  *
2577  * - encoding: unused
2578  * - decoding: set by the caller before avcodec_open2().
2579  */
2581 
2582  /* - encoding parameters */
2583  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2584  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2585 
2586  /**
2587  * minimum quantizer
2588  * - encoding: Set by user.
2589  * - decoding: unused
2590  */
2591  int qmin;
2592 
2593  /**
2594  * maximum quantizer
2595  * - encoding: Set by user.
2596  * - decoding: unused
2597  */
2598  int qmax;
2599 
2600  /**
2601  * maximum quantizer difference between frames
2602  * - encoding: Set by user.
2603  * - decoding: unused
2604  */
2606 
2607 #if FF_API_MPV_OPT
2608  /**
2609  * @deprecated use encoder private options instead
2610  */
2612  float rc_qsquish;
2613 
2618 #endif
2619 
2620  /**
2621  * decoder bitstream buffer size
2622  * - encoding: Set by user.
2623  * - decoding: unused
2624  */
2626 
2627  /**
2628  * ratecontrol override, see RcOverride
2629  * - encoding: Allocated/set/freed by user.
2630  * - decoding: unused
2631  */
2634 
2635 #if FF_API_MPV_OPT
2636  /**
2637  * @deprecated use encoder private options instead
2638  */
2640  const char *rc_eq;
2641 #endif
2642 
2643  /**
2644  * maximum bitrate
2645  * - encoding: Set by user.
2646  * - decoding: Set by user, may be overwritten by libavcodec.
2647  */
2648  int64_t rc_max_rate;
2649 
2650  /**
2651  * minimum bitrate
2652  * - encoding: Set by user.
2653  * - decoding: unused
2654  */
2655  int64_t rc_min_rate;
2656 
2657 #if FF_API_MPV_OPT
2658  /**
2659  * @deprecated use encoder private options instead
2660  */
2663 
2666 #endif
2667 
2668  /**
2669  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2670  * - encoding: Set by user.
2671  * - decoding: unused.
2672  */
2674 
2675  /**
2676  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2677  * - encoding: Set by user.
2678  * - decoding: unused.
2679  */
2681 
2682  /**
2683  * Number of bits which should be loaded into the rc buffer before decoding starts.
2684  * - encoding: Set by user.
2685  * - decoding: unused
2686  */
2688 
2689 #if FF_API_CODER_TYPE
2690 #define FF_CODER_TYPE_VLC 0
2691 #define FF_CODER_TYPE_AC 1
2692 #define FF_CODER_TYPE_RAW 2
2693 #define FF_CODER_TYPE_RLE 3
2694 #if FF_API_UNUSED_MEMBERS
2695 #define FF_CODER_TYPE_DEFLATE 4
2696 #endif /* FF_API_UNUSED_MEMBERS */
2697  /**
2698  * @deprecated use encoder private options instead
2699  */
2702 #endif /* FF_API_CODER_TYPE */
2703 
2704 #if FF_API_PRIVATE_OPT
2705  /** @deprecated use encoder private options instead */
2708 #endif
2709 
2710 #if FF_API_MPV_OPT
2711  /**
2712  * @deprecated use encoder private options instead
2713  */
2715  int lmin;
2716 
2717  /**
2718  * @deprecated use encoder private options instead
2719  */
2721  int lmax;
2722 #endif
2723 
2724 #if FF_API_PRIVATE_OPT
2725  /** @deprecated use encoder private options instead */
2728 
2729  /** @deprecated use encoder private options instead */
2732 
2733  /** @deprecated use encoder private options instead */
2736 
2737  /** @deprecated use encoder private options instead */
2740 #endif /* FF_API_PRIVATE_OPT */
2741 
2742  /**
2743  * trellis RD quantization
2744  * - encoding: Set by user.
2745  * - decoding: unused
2746  */
2747  int trellis;
2748 
2749 #if FF_API_PRIVATE_OPT
2750  /** @deprecated use encoder private options instead */
2753 
2754  /** @deprecated use encoder private options instead */
2757 
2758  /** @deprecated use encoder private options instead */
2761 #endif
2762 
2763 #if FF_API_RTP_CALLBACK
2764  /**
2765  * @deprecated unused
2766  */
2767  /* The RTP callback: This function is called */
2768  /* every time the encoder has a packet to send. */
2769  /* It depends on the encoder if the data starts */
2770  /* with a Start Code (it should). H.263 does. */
2771  /* mb_nb contains the number of macroblocks */
2772  /* encoded in the RTP payload. */
2774  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2775 #endif
2776 
2777 #if FF_API_PRIVATE_OPT
2778  /** @deprecated use encoder private options instead */
2780  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2781  /* do its best to deliver a chunk with size */
2782  /* below rtp_payload_size, the chunk will start */
2783  /* with a start code on some codecs like H.263. */
2784  /* This doesn't take account of any particular */
2785  /* headers inside the transmitted RTP payload. */
2786 #endif
2787 
2788 #if FF_API_STAT_BITS
2789  /* statistics, used for 2-pass encoding */
2791  int mv_bits;
2799  int i_count;
2801  int p_count;
2806 
2807  /** @deprecated this field is unused */
2810 #endif
2811 
2812  /**
2813  * pass1 encoding statistics output buffer
2814  * - encoding: Set by libavcodec.
2815  * - decoding: unused
2816  */
2817  char *stats_out;
2818 
2819  /**
2820  * pass2 encoding statistics input buffer
2821  * Concatenated stuff from stats_out of pass1 should be placed here.
2822  * - encoding: Allocated/set/freed by user.
2823  * - decoding: unused
2824  */
2825  char *stats_in;
2826 
2827  /**
2828  * Work around bugs in encoders which sometimes cannot be detected automatically.
2829  * - encoding: Set by user
2830  * - decoding: Set by user
2831  */
2833 #define FF_BUG_AUTODETECT 1 ///< autodetection
2834 #if FF_API_OLD_MSMPEG4
2835 #define FF_BUG_OLD_MSMPEG4 2
2836 #endif
2837 #define FF_BUG_XVID_ILACE 4
2838 #define FF_BUG_UMP4 8
2839 #define FF_BUG_NO_PADDING 16
2840 #define FF_BUG_AMV 32
2841 #if FF_API_AC_VLC
2842 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2843 #endif
2844 #define FF_BUG_QPEL_CHROMA 64
2845 #define FF_BUG_STD_QPEL 128
2846 #define FF_BUG_QPEL_CHROMA2 256
2847 #define FF_BUG_DIRECT_BLOCKSIZE 512
2848 #define FF_BUG_EDGE 1024
2849 #define FF_BUG_HPEL_CHROMA 2048
2850 #define FF_BUG_DC_CLIP 4096
2851 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2852 #define FF_BUG_TRUNCATED 16384
2853 
2854  /**
2855  * strictly follow the standard (MPEG-4, ...).
2856  * - encoding: Set by user.
2857  * - decoding: Set by user.
2858  * Setting this to STRICT or higher means the encoder and decoder will
2859  * generally do stupid things, whereas setting it to unofficial or lower
2860  * will mean the encoder might produce output that is not supported by all
2861  * spec-compliant decoders. Decoders don't differentiate between normal,
2862  * unofficial and experimental (that is, they always try to decode things
2863  * when they can) unless they are explicitly asked to behave stupidly
2864  * (=strictly conform to the specs)
2865  */
2867 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2868 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2869 #define FF_COMPLIANCE_NORMAL 0
2870 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2871 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2872 
2873  /**
2874  * error concealment flags
2875  * - encoding: unused
2876  * - decoding: Set by user.
2877  */
2879 #define FF_EC_GUESS_MVS 1
2880 #define FF_EC_DEBLOCK 2
2881 #define FF_EC_FAVOR_INTER 256
2882 
2883  /**
2884  * debug
2885  * - encoding: Set by user.
2886  * - decoding: Set by user.
2887  */
2888  int debug;
2889 #define FF_DEBUG_PICT_INFO 1
2890 #define FF_DEBUG_RC 2
2891 #define FF_DEBUG_BITSTREAM 4
2892 #define FF_DEBUG_MB_TYPE 8
2893 #define FF_DEBUG_QP 16
2894 #if FF_API_DEBUG_MV
2895 /**
2896  * @deprecated this option does nothing
2897  */
2898 #define FF_DEBUG_MV 32
2899 #endif
2900 #define FF_DEBUG_DCT_COEFF 0x00000040
2901 #define FF_DEBUG_SKIP 0x00000080
2902 #define FF_DEBUG_STARTCODE 0x00000100
2903 #if FF_API_UNUSED_MEMBERS
2904 #define FF_DEBUG_PTS 0x00000200
2905 #endif /* FF_API_UNUSED_MEMBERS */
2906 #define FF_DEBUG_ER 0x00000400
2907 #define FF_DEBUG_MMCO 0x00000800
2908 #define FF_DEBUG_BUGS 0x00001000
2909 #if FF_API_DEBUG_MV
2910 #define FF_DEBUG_VIS_QP 0x00002000 ///< only access through AVOptions from outside libavcodec
2911 #define FF_DEBUG_VIS_MB_TYPE 0x00004000 ///< only access through AVOptions from outside libavcodec
2912 #endif
2913 #define FF_DEBUG_BUFFERS 0x00008000
2914 #define FF_DEBUG_THREADS 0x00010000
2915 #define FF_DEBUG_GREEN_MD 0x00800000
2916 #define FF_DEBUG_NOMC 0x01000000
2917 
2918 #if FF_API_DEBUG_MV
2919  /**
2920  * debug
2921  * Code outside libavcodec should access this field using AVOptions
2922  * - encoding: Set by user.
2923  * - decoding: Set by user.
2924  */
2926 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2927 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2928 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2929 #endif
2930 
2931  /**
2932  * Error recognition; may misdetect some more or less valid parts as errors.
2933  * - encoding: unused
2934  * - decoding: Set by user.
2935  */
2937 
2938 /**
2939  * Verify checksums embedded in the bitstream (could be of either encoded or
2940  * decoded data, depending on the codec) and print an error message on mismatch.
2941  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2942  * decoder returning an error.
2943  */
2944 #define AV_EF_CRCCHECK (1<<0)
2945 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2946 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2947 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2948 
2949 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2950 #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
2951 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2952 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2953 
2954 
2955  /**
2956  * opaque 64-bit number (generally a PTS) that will be reordered and
2957  * output in AVFrame.reordered_opaque
2958  * - encoding: unused
2959  * - decoding: Set by user.
2960  */
2962 
2963  /**
2964  * Hardware accelerator in use
2965  * - encoding: unused.
2966  * - decoding: Set by libavcodec
2967  */
2969 
2970  /**
2971  * Hardware accelerator context.
2972  * For some hardware accelerators, a global context needs to be
2973  * provided by the user. In that case, this holds display-dependent
2974  * data FFmpeg cannot instantiate itself. Please refer to the
2975  * FFmpeg HW accelerator documentation to know how to fill this
2976  * is. e.g. for VA API, this is a struct vaapi_context.
2977  * - encoding: unused
2978  * - decoding: Set by user
2979  */
2981 
2982  /**
2983  * error
2984  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2985  * - decoding: unused
2986  */
2988 
2989  /**
2990  * DCT algorithm, see FF_DCT_* below
2991  * - encoding: Set by user.
2992  * - decoding: unused
2993  */
2995 #define FF_DCT_AUTO 0
2996 #define FF_DCT_FASTINT 1
2997 #define FF_DCT_INT 2
2998 #define FF_DCT_MMX 3
2999 #define FF_DCT_ALTIVEC 5
3000 #define FF_DCT_FAAN 6
3001 
3002  /**
3003  * IDCT algorithm, see FF_IDCT_* below.
3004  * - encoding: Set by user.
3005  * - decoding: Set by user.
3006  */
3008 #define FF_IDCT_AUTO 0
3009 #define FF_IDCT_INT 1
3010 #define FF_IDCT_SIMPLE 2
3011 #define FF_IDCT_SIMPLEMMX 3
3012 #define FF_IDCT_ARM 7
3013 #define FF_IDCT_ALTIVEC 8
3014 #if FF_API_ARCH_SH4
3015 #define FF_IDCT_SH4 9
3016 #endif
3017 #define FF_IDCT_SIMPLEARM 10
3018 #if FF_API_UNUSED_MEMBERS
3019 #define FF_IDCT_IPP 13
3020 #endif /* FF_API_UNUSED_MEMBERS */
3021 #define FF_IDCT_XVID 14
3022 #if FF_API_IDCT_XVIDMMX
3023 #define FF_IDCT_XVIDMMX 14
3024 #endif /* FF_API_IDCT_XVIDMMX */
3025 #define FF_IDCT_SIMPLEARMV5TE 16
3026 #define FF_IDCT_SIMPLEARMV6 17
3027 #if FF_API_ARCH_SPARC
3028 #define FF_IDCT_SIMPLEVIS 18
3029 #endif
3030 #define FF_IDCT_FAAN 20
3031 #define FF_IDCT_SIMPLENEON 22
3032 #if FF_API_ARCH_ALPHA
3033 #define FF_IDCT_SIMPLEALPHA 23
3034 #endif
3035 #define FF_IDCT_SIMPLEAUTO 128
3036 
3037  /**
3038  * bits per sample/pixel from the demuxer (needed for huffyuv).
3039  * - encoding: Set by libavcodec.
3040  * - decoding: Set by user.
3041  */
3043 
3044  /**
3045  * Bits per sample/pixel of internal libavcodec pixel/sample format.
3046  * - encoding: set by user.
3047  * - decoding: set by libavcodec.
3048  */
3050 
3051 #if FF_API_LOWRES
3052  /**
3053  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3054  * - encoding: unused
3055  * - decoding: Set by user.
3056  * Code outside libavcodec should access this field using:
3057  * av_codec_{get,set}_lowres(avctx)
3058  */
3059  int lowres;
3060 #endif
3061 
3062 #if FF_API_CODED_FRAME
3063  /**
3064  * the picture in the bitstream
3065  * - encoding: Set by libavcodec.
3066  * - decoding: unused
3067  *
3068  * @deprecated use the quality factor packet side data instead
3069  */
3071 #endif
3072 
3073  /**
3074  * thread count
3075  * is used to decide how many independent tasks should be passed to execute()
3076  * - encoding: Set by user.
3077  * - decoding: Set by user.
3078  */
3080 
3081  /**
3082  * Which multithreading methods to use.
3083  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
3084  * so clients which cannot provide future frames should not use it.
3085  *
3086  * - encoding: Set by user, otherwise the default is used.
3087  * - decoding: Set by user, otherwise the default is used.
3088  */
3090 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
3091 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
3092 
3093  /**
3094  * Which multithreading methods are in use by the codec.
3095  * - encoding: Set by libavcodec.
3096  * - decoding: Set by libavcodec.
3097  */
3099 
3100  /**
3101  * Set by the client if its custom get_buffer() callback can be called
3102  * synchronously from another thread, which allows faster multithreaded decoding.
3103  * draw_horiz_band() will be called from other threads regardless of this setting.
3104  * Ignored if the default get_buffer() is used.
3105  * - encoding: Set by user.
3106  * - decoding: Set by user.
3107  */
3109 
3110  /**
3111  * The codec may call this to execute several independent things.
3112  * It will return only after finishing all tasks.
3113  * The user may replace this with some multithreaded implementation,
3114  * the default implementation will execute the parts serially.
3115  * @param count the number of things to execute
3116  * - encoding: Set by libavcodec, user can override.
3117  * - decoding: Set by libavcodec, user can override.
3118  */
3119  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
3120 
3121  /**
3122  * The codec may call this to execute several independent things.
3123  * It will return only after finishing all tasks.
3124  * The user may replace this with some multithreaded implementation,
3125  * the default implementation will execute the parts serially.
3126  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
3127  * @param c context passed also to func
3128  * @param count the number of things to execute
3129  * @param arg2 argument passed unchanged to func
3130  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
3131  * @param func function that will be called count times, with jobnr from 0 to count-1.
3132  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
3133  * two instances of func executing at the same time will have the same threadnr.
3134  * @return always 0 currently, but code should handle a future improvement where when any call to func
3135  * returns < 0 no further calls to func may be done and < 0 is returned.
3136  * - encoding: Set by libavcodec, user can override.
3137  * - decoding: Set by libavcodec, user can override.
3138  */
3139  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
3140 
3141  /**
3142  * noise vs. sse weight for the nsse comparison function
3143  * - encoding: Set by user.
3144  * - decoding: unused
3145  */
3147 
3148  /**
3149  * profile
3150  * - encoding: Set by user.
3151  * - decoding: Set by libavcodec.
3152  */
3153  int profile;
3154 #define FF_PROFILE_UNKNOWN -99
3155 #define FF_PROFILE_RESERVED -100
3156 
3157 #define FF_PROFILE_AAC_MAIN 0
3158 #define FF_PROFILE_AAC_LOW 1
3159 #define FF_PROFILE_AAC_SSR 2
3160 #define FF_PROFILE_AAC_LTP 3
3161 #define FF_PROFILE_AAC_HE 4
3162 #define FF_PROFILE_AAC_HE_V2 28
3163 #define FF_PROFILE_AAC_LD 22
3164 #define FF_PROFILE_AAC_ELD 38
3165 #define FF_PROFILE_MPEG2_AAC_LOW 128
3166 #define FF_PROFILE_MPEG2_AAC_HE 131
3167 
3168 #define FF_PROFILE_DTS 20
3169 #define FF_PROFILE_DTS_ES 30
3170 #define FF_PROFILE_DTS_96_24 40
3171 #define FF_PROFILE_DTS_HD_HRA 50
3172 #define FF_PROFILE_DTS_HD_MA 60
3173 #define FF_PROFILE_DTS_EXPRESS 70
3174 
3175 #define FF_PROFILE_MPEG2_422 0
3176 #define FF_PROFILE_MPEG2_HIGH 1
3177 #define FF_PROFILE_MPEG2_SS 2
3178 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
3179 #define FF_PROFILE_MPEG2_MAIN 4
3180 #define FF_PROFILE_MPEG2_SIMPLE 5
3181 
3182 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
3183 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
3184 
3185 #define FF_PROFILE_H264_BASELINE 66
3186 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
3187 #define FF_PROFILE_H264_MAIN 77
3188 #define FF_PROFILE_H264_EXTENDED 88
3189 #define FF_PROFILE_H264_HIGH 100
3190 #define FF_PROFILE_H264_HIGH_10 110
3191 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
3192 #define FF_PROFILE_H264_HIGH_422 122
3193 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
3194 #define FF_PROFILE_H264_HIGH_444 144
3195 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
3196 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
3197 #define FF_PROFILE_H264_CAVLC_444 44
3198 
3199 #define FF_PROFILE_VC1_SIMPLE 0
3200 #define FF_PROFILE_VC1_MAIN 1
3201 #define FF_PROFILE_VC1_COMPLEX 2
3202 #define FF_PROFILE_VC1_ADVANCED 3
3203 
3204 #define FF_PROFILE_MPEG4_SIMPLE 0
3205 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
3206 #define FF_PROFILE_MPEG4_CORE 2
3207 #define FF_PROFILE_MPEG4_MAIN 3
3208 #define FF_PROFILE_MPEG4_N_BIT 4
3209 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
3210 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
3211 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
3212 #define FF_PROFILE_MPEG4_HYBRID 8
3213 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
3214 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
3215 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
3216 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
3217 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
3218 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
3219 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
3220 
3221 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
3222 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
3223 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
3224 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
3225 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
3226 
3227 #define FF_PROFILE_VP9_0 0
3228 #define FF_PROFILE_VP9_1 1
3229 #define FF_PROFILE_VP9_2 2
3230 #define FF_PROFILE_VP9_3 3
3231 
3232 #define FF_PROFILE_HEVC_MAIN 1
3233 #define FF_PROFILE_HEVC_MAIN_10 2
3234 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
3235 #define FF_PROFILE_HEVC_REXT 4
3236 
3237  /**
3238  * level
3239  * - encoding: Set by user.
3240  * - decoding: Set by libavcodec.
3241  */
3242  int level;
3243 #define FF_LEVEL_UNKNOWN -99
3244 
3245  /**
3246  * Skip loop filtering for selected frames.
3247  * - encoding: unused
3248  * - decoding: Set by user.
3249  */
3251 
3252  /**
3253  * Skip IDCT/dequantization for selected frames.
3254  * - encoding: unused
3255  * - decoding: Set by user.
3256  */
3258 
3259  /**
3260  * Skip decoding for selected frames.
3261  * - encoding: unused
3262  * - decoding: Set by user.
3263  */
3265 
3266  /**
3267  * Header containing style information for text subtitles.
3268  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3269  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3270  * the Format line following. It shouldn't include any Dialogue line.
3271  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3272  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3273  */
3276 
3277 #if FF_API_ERROR_RATE
3278  /**
3279  * @deprecated use the 'error_rate' private AVOption of the mpegvideo
3280  * encoders
3281  */
3284 #endif
3285 
3286 #if FF_API_VBV_DELAY
3287  /**
3288  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3289  * Used for compliant TS muxing.
3290  * - encoding: Set by libavcodec.
3291  * - decoding: unused.
3292  * @deprecated this value is now exported as a part of
3293  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3294  */
3296  uint64_t vbv_delay;
3297 #endif
3298 
3299 #if FF_API_SIDEDATA_ONLY_PKT
3300  /**
3301  * Encoding only and set by default. Allow encoders to output packets
3302  * that do not contain any encoded data, only side data.
3303  *
3304  * Some encoders need to output such packets, e.g. to update some stream
3305  * parameters at the end of encoding.
3306  *
3307  * @deprecated this field disables the default behaviour and
3308  * it is kept only for compatibility.
3309  */
3312 #endif
3313 
3314  /**
3315  * Audio only. The number of "priming" samples (padding) inserted by the
3316  * encoder at the beginning of the audio. I.e. this number of leading
3317  * decoded samples must be discarded by the caller to get the original audio
3318  * without leading padding.
3319  *
3320  * - decoding: unused
3321  * - encoding: Set by libavcodec. The timestamps on the output packets are
3322  * adjusted by the encoder so that they always refer to the
3323  * first sample of the data actually contained in the packet,
3324  * including any added padding. E.g. if the timebase is
3325  * 1/samplerate and the timestamp of the first input sample is
3326  * 0, the timestamp of the first output packet will be
3327  * -initial_padding.
3328  */
3330 
3331  /**
3332  * - decoding: For codecs that store a framerate value in the compressed
3333  * bitstream, the decoder may export it here. { 0, 1} when
3334  * unknown.
3335  * - encoding: May be used to signal the framerate of CFR content to an
3336  * encoder.
3337  */
3339 
3340  /**
3341  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3342  * - encoding: unused.
3343  * - decoding: Set by libavcodec before calling get_format()
3344  */
3346 
3347  /**
3348  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3349  * Code outside libavcodec should access this field using:
3350  * av_codec_{get,set}_pkt_timebase(avctx)
3351  * - encoding unused.
3352  * - decoding set by user.
3353  */
3355 
3356  /**
3357  * AVCodecDescriptor
3358  * Code outside libavcodec should access this field using:
3359  * av_codec_{get,set}_codec_descriptor(avctx)
3360  * - encoding: unused.
3361  * - decoding: set by libavcodec.
3362  */
3364 
3365 #if !FF_API_LOWRES
3366  /**
3367  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3368  * - encoding: unused
3369  * - decoding: Set by user.
3370  * Code outside libavcodec should access this field using:
3371  * av_codec_{get,set}_lowres(avctx)
3372  */
3373  int lowres;
3374 #endif
3375 
3376  /**
3377  * Current statistics for PTS correction.
3378  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3379  * - encoding: unused
3380  */
3381  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3382  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3383  int64_t pts_correction_last_pts; /// PTS of the last frame
3384  int64_t pts_correction_last_dts; /// DTS of the last frame
3385 
3386  /**
3387  * Character encoding of the input subtitles file.
3388  * - decoding: set by user
3389  * - encoding: unused
3390  */
3392 
3393  /**
3394  * Subtitles character encoding mode. Formats or codecs might be adjusting
3395  * this setting (if they are doing the conversion themselves for instance).
3396  * - decoding: set by libavcodec
3397  * - encoding: unused
3398  */
3400 #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)
3401 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3402 #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
3403 
3404  /**
3405  * Skip processing alpha if supported by codec.
3406  * Note that if the format uses pre-multiplied alpha (common with VP6,
3407  * and recommended due to better video quality/compression)
3408  * the image will look as if alpha-blended onto a black background.
3409  * However for formats that do not use pre-multiplied alpha
3410  * there might be serious artefacts (though e.g. libswscale currently
3411  * assumes pre-multiplied alpha anyway).
3412  * Code outside libavcodec should access this field using AVOptions
3413  *
3414  * - decoding: set by user
3415  * - encoding: unused
3416  */
3418 
3419  /**
3420  * Number of samples to skip after a discontinuity
3421  * - decoding: unused
3422  * - encoding: set by libavcodec
3423  */
3425 
3426 #if !FF_API_DEBUG_MV
3427  /**
3428  * debug motion vectors
3429  * Code outside libavcodec should access this field using AVOptions
3430  * - encoding: Set by user.
3431  * - decoding: Set by user.
3432  */
3433  int debug_mv;
3434 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3435 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3436 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3437 #endif
3438 
3439  /**
3440  * custom intra quantization matrix
3441  * Code outside libavcodec should access this field using av_codec_g/set_chroma_intra_matrix()
3442  * - encoding: Set by user, can be NULL.
3443  * - decoding: unused.
3444  */
3446 
3447  /**
3448  * dump format separator.
3449  * can be ", " or "\n " or anything else
3450  * Code outside libavcodec should access this field using AVOptions
3451  * (NO direct access).
3452  * - encoding: Set by user.
3453  * - decoding: Set by user.
3454  */
3456 
3457  /**
3458  * ',' separated list of allowed decoders.
3459  * If NULL then all are allowed
3460  * - encoding: unused
3461  * - decoding: set by user through AVOPtions (NO direct access)
3462  */
3464 
3465  /*
3466  * Properties of the stream that gets decoded
3467  * To be accessed through av_codec_get_properties() (NO direct access)
3468  * - encoding: unused
3469  * - decoding: set by libavcodec
3470  */
3471  unsigned properties;
3472 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3473 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3474 
3475  /**
3476  * Additional data associated with the entire coded stream.
3477  *
3478  * - decoding: unused
3479  * - encoding: may be set by libavcodec after avcodec_open2().
3480  */
3483 
3484  /**
3485  * Encoding only.
3486  *
3487  * For hardware encoders configured to use a hwaccel pixel format, this
3488  * field should be set by the caller to a reference to the AVHWFramesContext
3489  * describing input frames. AVHWFramesContext.format must be equal to
3490  * AVCodecContext.pix_fmt.
3491  *
3492  * This field should be set before avcodec_open2() is called and is
3493  * afterwards owned and managed by libavcodec.
3494  */
3496 
3497  /**
3498  * Control the form of AVSubtitle.rects[N]->ass
3499  * - decoding: set by user
3500  * - encoding: unused
3501  */
3503 #define FF_SUB_TEXT_FMT_ASS 0
3504 #if FF_API_ASS_TIMING
3505 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3506 #endif
3507 
3508 } AVCodecContext;
3509 
3512 
3515 
3516 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3517 
3518 int av_codec_get_lowres(const AVCodecContext *avctx);
3519 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3520 
3521 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3522 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3523 
3524 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3525 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3526 
3527 /**
3528  * AVProfile.
3529  */
3530 typedef struct AVProfile {
3531  int profile;
3532  const char *name; ///< short name for the profile
3533 } AVProfile;
3534 
3535 typedef struct AVCodecDefault AVCodecDefault;
3536 
3537 struct AVSubtitle;
3538 
3539 /**
3540  * AVCodec.
3541  */
3542 typedef struct AVCodec {
3543  /**
3544  * Name of the codec implementation.
3545  * The name is globally unique among encoders and among decoders (but an
3546  * encoder and a decoder can share the same name).
3547  * This is the primary way to find a codec from the user perspective.
3548  */
3549  const char *name;
3550  /**
3551  * Descriptive name for the codec, meant to be more human readable than name.
3552  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3553  */
3554  const char *long_name;
3557  /**
3558  * Codec capabilities.
3559  * see AV_CODEC_CAP_*
3560  */
3562  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3563  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3564  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3565  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3566  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3567  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder, no direct access, use av_codec_get_max_lowres()
3568  const AVClass *priv_class; ///< AVClass for the private context
3569  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3570 
3571  /*****************************************************************
3572  * No fields below this line are part of the public API. They
3573  * may not be used outside of libavcodec and can be changed and
3574  * removed at will.
3575  * New public fields should be added right above.
3576  *****************************************************************
3577  */
3579  struct AVCodec *next;
3580  /**
3581  * @name Frame-level threading support functions
3582  * @{
3583  */
3584  /**
3585  * If defined, called on thread contexts when they are created.
3586  * If the codec allocates writable tables in init(), re-allocate them here.
3587  * priv_data will be set to a copy of the original.
3588  */
3590  /**
3591  * Copy necessary context variables from a previous thread context to the current one.
3592  * If not defined, the next thread will start automatically; otherwise, the codec
3593  * must call ff_thread_finish_setup().
3594  *
3595  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3596  */
3598  /** @} */
3599 
3600  /**
3601  * Private codec-specific defaults.
3602  */
3604 
3605  /**
3606  * Initialize codec static data, called from avcodec_register().
3607  */
3608  void (*init_static_data)(struct AVCodec *codec);
3609 
3611  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3612  const struct AVSubtitle *sub);
3613  /**
3614  * Encode data to an AVPacket.
3615  *
3616  * @param avctx codec context
3617  * @param avpkt output AVPacket (may contain a user-provided buffer)
3618  * @param[in] frame AVFrame containing the raw data to be encoded
3619  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3620  * non-empty packet was returned in avpkt.
3621  * @return 0 on success, negative error code on failure
3622  */
3623  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3624  int *got_packet_ptr);
3625  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3627  /**
3628  * Decode/encode API with decoupled packet/frame dataflow. The API is the
3629  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3630  * that:
3631  * - never called if the codec is closed or the wrong type,
3632  * - AVPacket parameter change side data is applied right before calling
3633  * AVCodec->send_packet,
3634  * - if AV_CODEC_CAP_DELAY is not set, drain packets or frames are never sent,
3635  * - only one drain packet is ever passed down (until the next flush()),
3636  * - a drain AVPacket is always NULL (no need to check for avpkt->size).
3637  */
3638  int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3639  int (*send_packet)(AVCodecContext *avctx, const AVPacket *avpkt);
3641  int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3642  /**
3643  * Flush buffers.
3644  * Will be called when seeking
3645  */
3647  /**
3648  * Internal codec capabilities.
3649  * See FF_CODEC_CAP_* in internal.h
3650  */
3652 } AVCodec;
3653 
3654 int av_codec_get_max_lowres(const AVCodec *codec);
3655 
3656 struct MpegEncContext;
3657 
3658 /**
3659  * @defgroup lavc_hwaccel AVHWAccel
3660  * @{
3661  */
3662 typedef struct AVHWAccel {
3663  /**
3664  * Name of the hardware accelerated codec.
3665  * The name is globally unique among encoders and among decoders (but an
3666  * encoder and a decoder can share the same name).
3667  */
3668  const char *name;
3669 
3670  /**
3671  * Type of codec implemented by the hardware accelerator.
3672  *
3673  * See AVMEDIA_TYPE_xxx
3674  */
3676 
3677  /**
3678  * Codec implemented by the hardware accelerator.
3679  *
3680  * See AV_CODEC_ID_xxx
3681  */
3683 
3684  /**
3685  * Supported pixel format.
3686  *
3687  * Only hardware accelerated formats are supported here.
3688  */
3690 
3691  /**
3692  * Hardware accelerated codec capabilities.
3693  * see HWACCEL_CODEC_CAP_*
3694  */
3696 
3697  /*****************************************************************
3698  * No fields below this line are part of the public API. They
3699  * may not be used outside of libavcodec and can be changed and
3700  * removed at will.
3701  * New public fields should be added right above.
3702  *****************************************************************
3703  */
3704  struct AVHWAccel *next;
3705 
3706  /**
3707  * Allocate a custom buffer
3708  */
3710 
3711  /**
3712  * Called at the beginning of each frame or field picture.
3713  *
3714  * Meaningful frame information (codec specific) is guaranteed to
3715  * be parsed at this point. This function is mandatory.
3716  *
3717  * Note that buf can be NULL along with buf_size set to 0.
3718  * Otherwise, this means the whole frame is available at this point.
3719  *
3720  * @param avctx the codec context
3721  * @param buf the frame data buffer base
3722  * @param buf_size the size of the frame in bytes
3723  * @return zero if successful, a negative value otherwise
3724  */
3725  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3726 
3727  /**
3728  * Callback for each slice.
3729  *
3730  * Meaningful slice information (codec specific) is guaranteed to
3731  * be parsed at this point. This function is mandatory.
3732  * The only exception is XvMC, that works on MB level.
3733  *
3734  * @param avctx the codec context
3735  * @param buf the slice data buffer base
3736  * @param buf_size the size of the slice in bytes
3737  * @return zero if successful, a negative value otherwise
3738  */
3739  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3740 
3741  /**
3742  * Called at the end of each frame or field picture.
3743  *
3744  * The whole picture is parsed at this point and can now be sent
3745  * to the hardware accelerator. This function is mandatory.
3746  *
3747  * @param avctx the codec context
3748  * @return zero if successful, a negative value otherwise
3749  */
3750  int (*end_frame)(AVCodecContext *avctx);
3751 
3752  /**
3753  * Size of per-frame hardware accelerator private data.
3754  *
3755  * Private data is allocated with av_mallocz() before
3756  * AVCodecContext.get_buffer() and deallocated after
3757  * AVCodecContext.release_buffer().
3758  */
3760 
3761  /**
3762  * Called for every Macroblock in a slice.
3763  *
3764  * XvMC uses it to replace the ff_mpv_decode_mb().
3765  * Instead of decoding to raw picture, MB parameters are
3766  * stored in an array provided by the video driver.
3767  *
3768  * @param s the mpeg context
3769  */
3771 
3772  /**
3773  * Initialize the hwaccel private data.
3774  *
3775  * This will be called from ff_get_format(), after hwaccel and
3776  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3777  * is allocated.
3778  */
3780 
3781  /**
3782  * Uninitialize the hwaccel private data.
3783  *
3784  * This will be called from get_format() or avcodec_close(), after hwaccel
3785  * and hwaccel_context are already uninitialized.
3786  */
3788 
3789  /**
3790  * Size of the private data to allocate in
3791  * AVCodecInternal.hwaccel_priv_data.
3792  */
3794 } AVHWAccel;
3795 
3796 /**
3797  * Hardware acceleration should be used for decoding even if the codec level
3798  * used is unknown or higher than the maximum supported level reported by the
3799  * hardware driver.
3800  *
3801  * It's generally a good idea to pass this flag unless you have a specific
3802  * reason not to, as hardware tends to under-report supported levels.
3803  */
3804 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3805 
3806 /**
3807  * Hardware acceleration can output YUV pixel formats with a different chroma
3808  * sampling than 4:2:0 and/or other than 8 bits per component.
3809  */
3810 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3811 
3812 /**
3813  * @}
3814  */
3815 
3816 #if FF_API_AVPICTURE
3817 /**
3818  * @defgroup lavc_picture AVPicture
3819  *
3820  * Functions for working with AVPicture
3821  * @{
3822  */
3823 
3824 /**
3825  * Picture data structure.
3826  *
3827  * Up to four components can be stored into it, the last component is
3828  * alpha.
3829  * @deprecated use AVFrame or imgutils functions instead
3830  */
3831 typedef struct AVPicture {
3833  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3835  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3836 } AVPicture;
3837 
3838 /**
3839  * @}
3840  */
3841 #endif
3842 
3845 
3846  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3847 
3848  /**
3849  * Plain text, the text field must be set by the decoder and is
3850  * authoritative. ass and pict fields may contain approximations.
3851  */
3853 
3854  /**
3855  * Formatted text, the ass field must be set by the decoder and is
3856  * authoritative. pict and text fields may contain approximations.
3857  */
3859 };
3860 
3861 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3862 
3863 typedef struct AVSubtitleRect {
3864  int x; ///< top left corner of pict, undefined when pict is not set
3865  int y; ///< top left corner of pict, undefined when pict is not set
3866  int w; ///< width of pict, undefined when pict is not set
3867  int h; ///< height of pict, undefined when pict is not set
3868  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3869 
3870 #if FF_API_AVPICTURE
3871  /**
3872  * @deprecated unused
3873  */
3876 #endif
3877  /**
3878  * data+linesize for the bitmap of this subtitle.
3879  * Can be set for text/ass as well once they are rendered.
3880  */
3882  int linesize[4];
3883 
3885 
3886  char *text; ///< 0 terminated plain UTF-8 text
3887 
3888  /**
3889  * 0 terminated ASS/SSA compatible event line.
3890  * The presentation of this is unaffected by the other values in this
3891  * struct.
3892  */
3893  char *ass;
3894 
3895  int flags;
3896 } AVSubtitleRect;
3897 
3898 typedef struct AVSubtitle {
3899  uint16_t format; /* 0 = graphics */
3900  uint32_t start_display_time; /* relative to packet pts, in ms */
3901  uint32_t end_display_time; /* relative to packet pts, in ms */
3902  unsigned num_rects;
3904  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3905 } AVSubtitle;
3906 
3907 /**
3908  * This struct describes the properties of an encoded stream.
3909  *
3910  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3911  * be allocated with avcodec_parameters_alloc() and freed with
3912  * avcodec_parameters_free().
3913  */
3914 typedef struct AVCodecParameters {
3915  /**
3916  * General type of the encoded data.
3917  */
3919  /**
3920  * Specific type of the encoded data (the codec used).
3921  */
3923  /**
3924  * Additional information about the codec (corresponds to the AVI FOURCC).
3925  */
3926  uint32_t codec_tag;
3927 
3928  /**
3929  * Extra binary data needed for initializing the decoder, codec-dependent.
3930  *
3931  * Must be allocated with av_malloc() and will be freed by
3932  * avcodec_parameters_free(). The allocated size of extradata must be at
3933  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3934  * bytes zeroed.
3935  */
3937  /**
3938  * Size of the extradata content in bytes.
3939  */
3941 
3942  /**
3943  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3944  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3945  */
3946  int format;
3947 
3948  /**
3949  * The average bitrate of the encoded data (in bits per second).
3950  */
3951  int64_t bit_rate;
3952 
3953  /**
3954  * The number of bits per sample in the codedwords.
3955  *
3956  * This is basically the bitrate per sample. It is mandatory for a bunch of
3957  * formats to actually decode them. It's the number of bits for one sample in
3958  * the actual coded bitstream.
3959  *
3960  * This could be for example 4 for ADPCM
3961  * For PCM formats this matches bits_per_raw_sample
3962  * Can be 0
3963  */
3965 
3966  /**
3967  * This is the number of valid bits in each output sample. If the
3968  * sample format has more bits, the least significant bits are additional
3969  * padding bits, which are always 0. Use right shifts to reduce the sample
3970  * to its actual size. For example, audio formats with 24 bit samples will
3971  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
3972  * To get the original sample use "(int32_t)sample >> 8"."
3973  *
3974  * For ADPCM this might be 12 or 16 or similar
3975  * Can be 0
3976  */
3978 
3979  /**
3980  * Codec-specific bitstream restrictions that the stream conforms to.
3981  */
3982  int profile;
3983  int level;
3984 
3985  /**
3986  * Video only. The dimensions of the video frame in pixels.
3987  */
3988  int width;
3989  int height;
3990 
3991  /**
3992  * Video only. The aspect ratio (width / height) which a single pixel
3993  * should have when displayed.
3994  *
3995  * When the aspect ratio is unknown / undefined, the numerator should be
3996  * set to 0 (the denominator may have any value).
3997  */
3999 
4000  /**
4001  * Video only. The order of the fields in interlaced video.
4002  */
4004 
4005  /**
4006  * Video only. Additional colorspace characteristics.
4007  */
4013 
4014  /**
4015  * Video only. Number of delayed frames.
4016  */
4018 
4019  /**
4020  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4021  * unknown or unspecified, otherwise the number of bits set must be equal to
4022  * the channels field.
4023  */
4024  uint64_t channel_layout;
4025  /**
4026  * Audio only. The number of audio channels.
4027  */
4029  /**
4030  * Audio only. The number of audio samples per second.
4031  */
4033  /**
4034  * Audio only. The number of bytes per coded audio frame, required by some
4035  * formats.
4036  *
4037  * Corresponds to nBlockAlign in WAVEFORMATEX.
4038  */
4040  /**
4041  * Audio only. Audio frame size, if known. Required by some formats to be static.
4042  */
4044 
4045  /**
4046  * Audio only. The amount of padding (in samples) inserted by the encoder at
4047  * the beginning of the audio. I.e. this number of leading decoded samples
4048  * must be discarded by the caller to get the original audio without leading
4049  * padding.
4050  */
4052  /**
4053  * Audio only. The amount of padding (in samples) appended by the encoder to
4054  * the end of the audio. I.e. this number of decoded samples must be
4055  * discarded by the caller from the end of the stream to get the original
4056  * audio without any trailing padding.
4057  */
4059  /**
4060  * Audio only. Number of samples to skip after a discontinuity.
4061  */
4064 
4065 /**
4066  * If c is NULL, returns the first registered codec,
4067  * if c is non-NULL, returns the next registered codec after c,
4068  * or NULL if c is the last one.
4069  */
4070 AVCodec *av_codec_next(const AVCodec *c);
4071 
4072 /**
4073  * Return the LIBAVCODEC_VERSION_INT constant.
4074  */
4075 unsigned avcodec_version(void);
4076 
4077 /**
4078  * Return the libavcodec build-time configuration.
4079  */
4080 const char *avcodec_configuration(void);
4081 
4082 /**
4083  * Return the libavcodec license.
4084  */
4085 const char *avcodec_license(void);
4086 
4087 /**
4088  * Register the codec codec and initialize libavcodec.
4089  *
4090  * @warning either this function or avcodec_register_all() must be called
4091  * before any other libavcodec functions.
4092  *
4093  * @see avcodec_register_all()
4094  */
4095 void avcodec_register(AVCodec *codec);
4096 
4097 /**
4098  * Register all the codecs, parsers and bitstream filters which were enabled at
4099  * configuration time. If you do not call this function you can select exactly
4100  * which formats you want to support, by using the individual registration
4101  * functions.
4102  *
4103  * @see avcodec_register
4104  * @see av_register_codec_parser
4105  * @see av_register_bitstream_filter
4106  */
4107 void avcodec_register_all(void);
4108 
4109 /**
4110  * Allocate an AVCodecContext and set its fields to default values. The
4111  * resulting struct should be freed with avcodec_free_context().
4112  *
4113  * @param codec if non-NULL, allocate private data and initialize defaults
4114  * for the given codec. It is illegal to then call avcodec_open2()
4115  * with a different codec.
4116  * If NULL, then the codec-specific defaults won't be initialized,
4117  * which may result in suboptimal default settings (this is
4118  * important mainly for encoders, e.g. libx264).
4119  *
4120  * @return An AVCodecContext filled with default values or NULL on failure.
4121  */
4123 
4124 /**
4125  * Free the codec context and everything associated with it and write NULL to
4126  * the provided pointer.
4127  */
4128 void avcodec_free_context(AVCodecContext **avctx);
4129 
4130 #if FF_API_GET_CONTEXT_DEFAULTS
4131 /**
4132  * @deprecated This function should not be used, as closing and opening a codec
4133  * context multiple time is not supported. A new codec context should be
4134  * allocated for each new use.
4135  */
4137 #endif
4138 
4139 /**
4140  * Get the AVClass for AVCodecContext. It can be used in combination with
4141  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4142  *
4143  * @see av_opt_find().
4144  */
4145 const AVClass *avcodec_get_class(void);
4146 
4147 #if FF_API_COPY_CONTEXT
4148 /**
4149  * Get the AVClass for AVFrame. It can be used in combination with
4150  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4151  *
4152  * @see av_opt_find().
4153  */
4154 const AVClass *avcodec_get_frame_class(void);
4155 
4156 /**
4157  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4158  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4159  *
4160  * @see av_opt_find().
4161  */
4163 
4164 /**
4165  * Copy the settings of the source AVCodecContext into the destination
4166  * AVCodecContext. The resulting destination codec context will be
4167  * unopened, i.e. you are required to call avcodec_open2() before you
4168  * can use this AVCodecContext to decode/encode video/audio data.
4169  *
4170  * @param dest target codec context, should be initialized with
4171  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4172  * @param src source codec context
4173  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4174  *
4175  * @deprecated The semantics of this function are ill-defined and it should not
4176  * be used. If you need to transfer the stream parameters from one codec context
4177  * to another, use an intermediate AVCodecParameters instance and the
4178  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4179  * functions.
4180  */
4183 #endif
4184 
4185 /**
4186  * Allocate a new AVCodecParameters and set its fields to default values
4187  * (unknown/invalid/0). The returned struct must be freed with
4188  * avcodec_parameters_free().
4189  */
4191 
4192 /**
4193  * Free an AVCodecParameters instance and everything associated with it and
4194  * write NULL to the supplied pointer.
4195  */
4197 
4198 /**
4199  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4200  * replaced with newly allocated duplicates of the corresponding fields in src.
4201  *
4202  * @return >= 0 on success, a negative AVERROR code on failure.
4203  */
4205 
4206 /**
4207  * Fill the parameters struct based on the values from the supplied codec
4208  * context. Any allocated fields in par are freed and replaced with duplicates
4209  * of the corresponding fields in codec.
4210  *
4211  * @return >= 0 on success, a negative AVERROR code on failure
4212  */
4214  const AVCodecContext *codec);
4215 
4216 /**
4217  * Fill the codec context based on the values from the supplied codec
4218  * parameters. Any allocated fields in codec that have a corresponding field in
4219  * par are freed and replaced with duplicates of the corresponding field in par.
4220  * Fields in codec that do not have a counterpart in par are not touched.
4221  *
4222  * @return >= 0 on success, a negative AVERROR code on failure.
4223  */
4225  const AVCodecParameters *par);
4226 
4227 /**
4228  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4229  * function the context has to be allocated with avcodec_alloc_context3().
4230  *
4231  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4232  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4233  * retrieving a codec.
4234  *
4235  * @warning This function is not thread safe!
4236  *
4237  * @note Always call this function before using decoding routines (such as
4238  * @ref avcodec_receive_frame()).
4239  *
4240  * @code
4241  * avcodec_register_all();
4242  * av_dict_set(&opts, "b", "2.5M", 0);
4243  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4244  * if (!codec)
4245  * exit(1);
4246  *
4247  * context = avcodec_alloc_context3(codec);
4248  *
4249  * if (avcodec_open2(context, codec, opts) < 0)
4250  * exit(1);
4251  * @endcode
4252  *
4253  * @param avctx The context to initialize.
4254  * @param codec The codec to open this context for. If a non-NULL codec has been
4255  * previously passed to avcodec_alloc_context3() or
4256  * for this context, then this parameter MUST be either NULL or
4257  * equal to the previously passed codec.
4258  * @param options A dictionary filled with AVCodecContext and codec-private options.
4259  * On return this object will be filled with options that were not found.
4260  *
4261  * @return zero on success, a negative value on error
4262  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4263  * av_dict_set(), av_opt_find().
4264  */
4265 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4266 
4267 /**
4268  * Close a given AVCodecContext and free all the data associated with it
4269  * (but not the AVCodecContext itself).
4270  *
4271  * Calling this function on an AVCodecContext that hasn't been opened will free
4272  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4273  * codec. Subsequent calls will do nothing.
4274  *
4275  * @note Do not use this function. Use avcodec_free_context() to destroy a
4276  * codec context (either open or closed). Opening and closing a codec context
4277  * multiple times is not supported anymore -- use multiple codec contexts
4278  * instead.
4279  */
4280 int avcodec_close(AVCodecContext *avctx);
4281 
4282 /**
4283  * Free all allocated data in the given subtitle struct.
4284  *
4285  * @param sub AVSubtitle to free.
4286  */
4287 void avsubtitle_free(AVSubtitle *sub);
4288 
4289 /**
4290  * @}
4291  */
4292 
4293 /**
4294  * @addtogroup lavc_packet
4295  * @{
4296  */
4297 
4298 /**
4299  * Allocate an AVPacket and set its fields to default values. The resulting
4300  * struct must be freed using av_packet_free().
4301  *
4302  * @return An AVPacket filled with default values or NULL on failure.
4303  *
4304  * @note this only allocates the AVPacket itself, not the data buffers. Those
4305  * must be allocated through other means such as av_new_packet.
4306  *
4307  * @see av_new_packet
4308  */
4309 AVPacket *av_packet_alloc(void);
4310 
4311 /**
4312  * Create a new packet that references the same data as src.
4313  *
4314  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4315  *
4316  * @return newly created AVPacket on success, NULL on error.
4317  *
4318  * @see av_packet_alloc
4319  * @see av_packet_ref
4320  */
4322 
4323 /**
4324  * Free the packet, if the packet is reference counted, it will be
4325  * unreferenced first.
4326  *
4327  * @param packet packet to be freed. The pointer will be set to NULL.
4328  * @note passing NULL is a no-op.
4329  */
4330 void av_packet_free(AVPacket **pkt);
4331 
4332 /**
4333  * Initialize optional fields of a packet with default values.
4334  *
4335  * Note, this does not touch the data and size members, which have to be
4336  * initialized separately.
4337  *
4338  * @param pkt packet
4339  */
4340 void av_init_packet(AVPacket *pkt);
4341 
4342 /**
4343  * Allocate the payload of a packet and initialize its fields with
4344  * default values.
4345  *
4346  * @param pkt packet
4347  * @param size wanted payload size
4348  * @return 0 if OK, AVERROR_xxx otherwise
4349  */
4350 int av_new_packet(AVPacket *pkt, int size);
4351 
4352 /**
4353  * Reduce packet size, correctly zeroing padding
4354  *
4355  * @param pkt packet
4356  * @param size new size
4357  */
4358 void av_shrink_packet(AVPacket *pkt, int size);
4359 
4360 /**
4361  * Increase packet size, correctly zeroing padding
4362  *
4363  * @param pkt packet
4364  * @param grow_by number of bytes by which to increase the size of the packet
4365  */
4366 int av_grow_packet(AVPacket *pkt, int grow_by);
4367 
4368 /**
4369  * Initialize a reference-counted packet from av_malloc()ed data.
4370  *
4371  * @param pkt packet to be initialized. This function will set the data, size,
4372  * buf and destruct fields, all others are left untouched.
4373  * @param data Data allocated by av_malloc() to be used as packet data. If this
4374  * function returns successfully, the data is owned by the underlying AVBuffer.
4375  * The caller may not access the data through other means.
4376  * @param size size of data in bytes, without the padding. I.e. the full buffer
4377  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4378  *
4379  * @return 0 on success, a negative AVERROR on error
4380  */
4382 
4383 #if FF_API_AVPACKET_OLD_API
4384 /**
4385  * @warning This is a hack - the packet memory allocation stuff is broken. The
4386  * packet is allocated if it was not really allocated.
4387  *
4388  * @deprecated Use av_packet_ref
4389  */
4391 int av_dup_packet(AVPacket *pkt);
4392 /**
4393  * Copy packet, including contents
4394  *
4395  * @return 0 on success, negative AVERROR on fail
4396  */
4397 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4398 
4399 /**
4400  * Copy packet side data
4401  *
4402  * @return 0 on success, negative AVERROR on fail
4403  */
4404 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4405 
4406 /**
4407  * Free a packet.
4408  *
4409  * @deprecated Use av_packet_unref
4410  *
4411  * @param pkt packet to free
4412  */
4414 void av_free_packet(AVPacket *pkt);
4415 #endif
4416 /**
4417  * Allocate new information of a packet.
4418  *
4419  * @param pkt packet
4420  * @param type side information type
4421  * @param size side information size
4422  * @return pointer to fresh allocated data or NULL otherwise
4423  */
4425  int size);
4426 
4427 /**
4428  * Wrap an existing array as a packet side data.
4429  *
4430  * @param pkt packet
4431  * @param type side information type
4432  * @param data the side data array. It must be allocated with the av_malloc()
4433  * family of functions. The ownership of the data is transferred to
4434  * pkt.
4435  * @param size side information size
4436  * @return a non-negative number on success, a negative AVERROR code on
4437  * failure. On failure, the packet is unchanged and the data remains
4438  * owned by the caller.
4439  */
4441  uint8_t *data, size_t size);
4442 
4443 /**
4444  * Shrink the already allocated side data buffer
4445  *
4446  * @param pkt packet
4447  * @param type side information type
4448  * @param size new side information size
4449  * @return 0 on success, < 0 on failure
4450  */
4452  int size);
4453 
4454 /**
4455  * Get side information from packet.
4456  *
4457  * @param pkt packet
4458  * @param type desired side information type
4459  * @param size pointer for side information size to store (optional)
4460  * @return pointer to data if present or NULL otherwise
4461  */
4463  int *size);
4464 
4466 
4468 
4470 
4471 /**
4472  * Pack a dictionary for use in side_data.
4473  *
4474  * @param dict The dictionary to pack.
4475  * @param size pointer to store the size of the returned data
4476  * @return pointer to data if successful, NULL otherwise
4477  */
4479 /**
4480  * Unpack a dictionary from side_data.
4481  *
4482  * @param data data from side_data
4483  * @param size size of the data
4484  * @param dict the metadata storage dictionary
4485  * @return 0 on success, < 0 on failure
4486  */
4487 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4488 
4489 
4490 /**
4491  * Convenience function to free all the side data stored.
4492  * All the other fields stay untouched.
4493  *
4494  * @param pkt packet
4495  */
4497 
4498 /**
4499  * Setup a new reference to the data described by a given packet
4500  *
4501  * If src is reference-counted, setup dst as a new reference to the
4502  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4503  * data from src into it.
4504  *
4505  * All the other fields are copied from src.
4506  *
4507  * @see av_packet_unref
4508  *
4509  * @param dst Destination packet
4510  * @param src Source packet
4511  *
4512  * @return 0 on success, a negative AVERROR on error.
4513  */
4514 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4515 
4516 /**
4517  * Wipe the packet.
4518  *
4519  * Unreference the buffer referenced by the packet and reset the
4520  * remaining packet fields to their default values.
4521  *
4522  * @param pkt The packet to be unreferenced.
4523  */
4525 
4526 /**
4527  * Move every field in src to dst and reset src.
4528  *
4529  * @see av_packet_unref
4530  *
4531  * @param src Source packet, will be reset
4532  * @param dst Destination packet
4533  */
4535 
4536 /**
4537  * Copy only "properties" fields from src to dst.
4538  *
4539  * Properties for the purpose of this function are all the fields
4540  * beside those related to the packet data (buf, data, size)
4541  *
4542  * @param dst Destination packet
4543  * @param src Source packet
4544  *
4545  * @return 0 on success AVERROR on failure.
4546  */
4547 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4548 
4549 /**
4550  * Convert valid timing fields (timestamps / durations) in a packet from one
4551  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4552  * ignored.
4553  *
4554  * @param pkt packet on which the conversion will be performed
4555  * @param tb_src source timebase, in which the timing fields in pkt are
4556  * expressed
4557  * @param tb_dst destination timebase, to which the timing fields will be
4558  * converted
4559  */
4560 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4561 
4562 /**
4563  * @}
4564  */
4565 
4566 /**
4567  * @addtogroup lavc_decoding
4568  * @{
4569  */
4570 
4571 /**
4572  * Find a registered decoder with a matching codec ID.
4573  *
4574  * @param id AVCodecID of the requested decoder
4575  * @return A decoder if one was found, NULL otherwise.
4576  */
4578 
4579 /**
4580  * Find a registered decoder with the specified name.
4581  *
4582  * @param name name of the requested decoder
4583  * @return A decoder if one was found, NULL otherwise.
4584  */
4586 
4587 /**
4588  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4589  * it can be called by custom get_buffer2() implementations for decoders without
4590  * AV_CODEC_CAP_DR1 set.
4591  */
4593 
4594 #if FF_API_EMU_EDGE
4595 /**
4596  * Return the amount of padding in pixels which the get_buffer callback must
4597  * provide around the edge of the image for codecs which do not have the
4598  * CODEC_FLAG_EMU_EDGE flag.
4599  *
4600  * @return Required padding in pixels.
4601  *
4602  * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
4603  * needed
4604  */
4606 unsigned avcodec_get_edge_width(void);
4607 #endif
4608 
4609 /**
4610  * Modify width and height values so that they will result in a memory
4611  * buffer that is acceptable for the codec if you do not use any horizontal
4612  * padding.
4613  *
4614  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4615  */
4617 
4618 /**
4619  * Modify width and height values so that they will result in a memory
4620  * buffer that is acceptable for the codec if you also ensure that all
4621  * line sizes are a multiple of the respective linesize_align[i].
4622  *
4623  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4624  */
4626  int linesize_align[AV_NUM_DATA_POINTERS]);
4627 
4628 /**
4629  * Converts AVChromaLocation to swscale x/y chroma position.
4630  *
4631  * The positions represent the chroma (0,0) position in a coordinates system
4632  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4633  *
4634  * @param xpos horizontal chroma sample position
4635  * @param ypos vertical chroma sample position
4636  */
4637 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4638 
4639 /**
4640  * Converts swscale x/y chroma position to AVChromaLocation.
4641  *
4642  * The positions represent the chroma (0,0) position in a coordinates system
4643  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4644  *
4645  * @param xpos horizontal chroma sample position
4646  * @param ypos vertical chroma sample position
4647  */
4648 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4649 
4650 /**
4651  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4652  *
4653  * Some decoders may support multiple frames in a single AVPacket. Such
4654  * decoders would then just decode the first frame and the return value would be
4655  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4656  * called again with an AVPacket containing the remaining data in order to
4657  * decode the second frame, etc... Even if no frames are returned, the packet
4658  * needs to be fed to the decoder with remaining data until it is completely
4659  * consumed or an error occurs.
4660  *
4661  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4662  * and output. This means that for some packets they will not immediately
4663  * produce decoded output and need to be flushed at the end of decoding to get
4664  * all the decoded data. Flushing is done by calling this function with packets
4665  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4666  * returning samples. It is safe to flush even those decoders that are not
4667  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4668  *
4669  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4670  * larger than the actual read bytes because some optimized bitstream
4671  * readers read 32 or 64 bits at once and could read over the end.
4672  *
4673  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4674  * before packets may be fed to the decoder.
4675  *
4676  * @param avctx the codec context
4677  * @param[out] frame The AVFrame in which to store decoded audio samples.
4678  * The decoder will allocate a buffer for the decoded frame by
4679  * calling the AVCodecContext.get_buffer2() callback.
4680  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4681  * reference counted and the returned reference belongs to the
4682  * caller. The caller must release the frame using av_frame_unref()
4683  * when the frame is no longer needed. The caller may safely write
4684  * to the frame if av_frame_is_writable() returns 1.
4685  * When AVCodecContext.refcounted_frames is set to 0, the returned
4686  * reference belongs to the decoder and is valid only until the
4687  * next call to this function or until closing or flushing the
4688  * decoder. The caller may not write to it.
4689  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4690  * non-zero. Note that this field being set to zero
4691  * does not mean that an error has occurred. For
4692  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4693  * call is guaranteed to produce a frame.
4694  * @param[in] avpkt The input AVPacket containing the input buffer.
4695  * At least avpkt->data and avpkt->size should be set. Some
4696  * decoders might also require additional fields to be set.
4697  * @return A negative error code is returned if an error occurred during
4698  * decoding, otherwise the number of bytes consumed from the input
4699  * AVPacket is returned.
4700  *
4701 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4702  */
4705  int *got_frame_ptr, const AVPacket *avpkt);
4706 
4707 /**
4708  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4709  * Some decoders may support multiple frames in a single AVPacket, such
4710  * decoders would then just decode the first frame.
4711  *
4712  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4713  * the actual read bytes because some optimized bitstream readers read 32 or 64
4714  * bits at once and could read over the end.
4715  *
4716  * @warning The end of the input buffer buf should be set to 0 to ensure that
4717  * no overreading happens for damaged MPEG streams.
4718  *
4719  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4720  * between input and output, these need to be fed with avpkt->data=NULL,
4721  * avpkt->size=0 at the end to return the remaining frames.
4722  *
4723  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4724  * before packets may be fed to the decoder.
4725  *
4726  * @param avctx the codec context
4727  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4728  * Use av_frame_alloc() to get an AVFrame. The codec will
4729  * allocate memory for the actual bitmap by calling the
4730  * AVCodecContext.get_buffer2() callback.
4731  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4732  * reference counted and the returned reference belongs to the
4733  * caller. The caller must release the frame using av_frame_unref()
4734  * when the frame is no longer needed. The caller may safely write
4735  * to the frame if av_frame_is_writable() returns 1.
4736  * When AVCodecContext.refcounted_frames is set to 0, the returned
4737  * reference belongs to the decoder and is valid only until the
4738  * next call to this function or until closing or flushing the
4739  * decoder. The caller may not write to it.
4740  *
4741  * @param[in] avpkt The input AVPacket containing the input buffer.
4742  * You can create such packet with av_init_packet() and by then setting
4743  * data and size, some decoders might in addition need other fields like
4744  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4745  * fields possible.
4746  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4747  * @return On error a negative value is returned, otherwise the number of bytes
4748  * used or zero if no frame could be decompressed.
4749  *
4750  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4751  */
4753 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4754  int *got_picture_ptr,
4755  const AVPacket *avpkt);
4756 
4757 /**
4758  * Decode a subtitle message.
4759  * Return a negative value on error, otherwise return the number of bytes used.
4760  * If no subtitle could be decompressed, got_sub_ptr is zero.
4761  * Otherwise, the subtitle is stored in *sub.
4762  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4763  * simplicity, because the performance difference is expect to be negligible
4764  * and reusing a get_buffer written for video codecs would probably perform badly
4765  * due to a potentially very different allocation pattern.
4766  *
4767  * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
4768  * and output. This means that for some packets they will not immediately
4769  * produce decoded output and need to be flushed at the end of decoding to get
4770  * all the decoded data. Flushing is done by calling this function with packets
4771  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4772  * returning subtitles. It is safe to flush even those decoders that are not
4773  * marked with CODEC_CAP_DELAY, then no subtitles will be returned.
4774  *
4775  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4776  * before packets may be fed to the decoder.
4777  *
4778  * @param avctx the codec context
4779  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4780  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4781  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4782  * @param[in] avpkt The input AVPacket containing the input buffer.
4783  */
4785  int *got_sub_ptr,
4786  AVPacket *avpkt);
4787 
4788 /**
4789  * Supply raw packet data as input to a decoder.
4790  *
4791  * Internally, this call will copy relevant AVCodecContext fields, which can
4792  * influence decoding per-packet, and apply them when the packet is actually
4793  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4794  * decoder to drop the frame contained by the packet sent with this function.)
4795  *
4796  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4797  * larger than the actual read bytes because some optimized bitstream
4798  * readers read 32 or 64 bits at once and could read over the end.
4799  *
4800  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4801  * on the same AVCodecContext. It will return unexpected results now
4802  * or in future libavcodec versions.
4803  *
4804  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4805  * before packets may be fed to the decoder.
4806  *
4807  * @param avctx codec context
4808  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4809  * frame, or several complete audio frames.
4810  * Ownership of the packet remains with the caller, and the
4811  * decoder will not write to the packet. The decoder may create
4812  * a reference to the packet data (or copy it if the packet is
4813  * not reference-counted).
4814  * Unlike with older APIs, the packet is always fully consumed,
4815  * and if it contains multiple frames (e.g. some audio codecs),
4816  * will require you to call avcodec_receive_frame() multiple
4817  * times afterwards before you can send a new packet.
4818  * It can be NULL (or an AVPacket with data set to NULL and
4819  * size set to 0); in this case, it is considered a flush
4820  * packet, which signals the end of the stream. Sending the
4821  * first flush packet will return success. Subsequent ones are
4822  * unnecessary and will return AVERROR_EOF. If the decoder
4823  * still has frames buffered, it will return them after sending
4824  * a flush packet.
4825  *
4826  * @return 0 on success, otherwise negative error code:
4827  * AVERROR(EAGAIN): input is not accepted right now - the packet must be
4828  * resent after trying to read output
4829  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4830  * be sent to it (also returned if more than 1 flush
4831  * packet is sent)
4832  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4833  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4834  * other errors: legitimate decoding errors
4835  */
4836 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4837 
4838 /**
4839  * Return decoded output data from a decoder.
4840  *
4841  * @param avctx codec context
4842  * @param frame This will be set to a reference-counted video or audio
4843  * frame (depending on the decoder type) allocated by the
4844  * decoder. Note that the function will always call
4845  * av_frame_unref(frame) before doing anything else.
4846  *
4847  * @return
4848  * 0: success, a frame was returned
4849  * AVERROR(EAGAIN): output is not available right now - user must try
4850  * to send new input
4851  * AVERROR_EOF: the decoder has been fully flushed, and there will be
4852  * no more output frames
4853  * AVERROR(EINVAL): codec not opened, or it is an encoder
4854  * other negative values: legitimate decoding errors
4855  */
4857 
4858 /**
4859  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4860  * to retrieve buffered output packets.
4861  *
4862  * @param avctx codec context
4863  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4864  * Ownership of the frame remains with the caller, and the
4865  * encoder will not write to the frame. The encoder may create
4866  * a reference to the frame data (or copy it if the frame is
4867  * not reference-counted).
4868  * It can be NULL, in which case it is considered a flush
4869  * packet. This signals the end of the stream. If the encoder
4870  * still has packets buffered, it will return them after this
4871  * call. Once flushing mode has been entered, additional flush
4872  * packets are ignored, and sending frames will return
4873  * AVERROR_EOF.
4874  *
4875  * For audio:
4876  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4877  * can have any number of samples.
4878  * If it is not set, frame->nb_samples must be equal to
4879  * avctx->frame_size for all frames except the last.
4880  * The final frame may be smaller than avctx->frame_size.
4881  * @return 0 on success, otherwise negative error code:
4882  * AVERROR(EAGAIN): input is not accepted right now - the frame must be
4883  * resent after trying to read output packets
4884  * AVERROR_EOF: the encoder has been flushed, and no new frames can
4885  * be sent to it
4886  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4887  * decoder, or requires flush
4888  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4889  * other errors: legitimate decoding errors
4890  */
4891 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4892 
4893 /**
4894  * Read encoded data from the encoder.
4895  *
4896  * @param avctx codec context
4897  * @param avpkt This will be set to a reference-counted packet allocated by the
4898  * encoder. Note that the function will always call
4899  * av_frame_unref(frame) before doing anything else.
4900  * @return 0 on success, otherwise negative error code:
4901  * AVERROR(EAGAIN): output is not available right now - user must try
4902  * to send input
4903  * AVERROR_EOF: the encoder has been fully flushed, and there will be
4904  * no more output packets
4905  * AVERROR(EINVAL): codec not opened, or it is an encoder
4906  * other errors: legitimate decoding errors
4907  */
4908 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4909 
4910 
4911 /**
4912  * @defgroup lavc_parsing Frame parsing
4913  * @{
4914  */
4915 
4918  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4919  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4920  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4921 };
4922 
4923 typedef struct AVCodecParserContext {
4924  void *priv_data;
4926  int64_t frame_offset; /* offset of the current frame */
4927  int64_t cur_offset; /* current offset
4928  (incremented by each av_parser_parse()) */
4929  int64_t next_frame_offset; /* offset of the next frame */
4930  /* video info */
4931  int pict_type; /* XXX: Put it back in AVCodecContext. */
4932  /**
4933  * This field is used for proper frame duration computation in lavf.
4934  * It signals, how much longer the frame duration of the current frame
4935  * is compared to normal frame duration.
4936  *
4937  * frame_duration = (1 + repeat_pict) * time_base
4938  *
4939  * It is used by codecs like H.264 to display telecined material.
4940  */
4941  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4942  int64_t pts; /* pts of the current frame */
4943  int64_t dts; /* dts of the current frame */
4944 
4945  /* private data */
4946  int64_t last_pts;
4947  int64_t last_dts;
4949 
4950 #define AV_PARSER_PTS_NB 4
4955 
4956  int flags;
4957 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4958 #define PARSER_FLAG_ONCE 0x0002
4959 /// Set if the parser has a valid file offset
4960 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4961 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4962 
4963  int64_t offset; ///< byte offset from starting packet start
4965 
4966  /**
4967  * Set by parser to 1 for key frames and 0 for non-key frames.
4968  * It is initialized to -1, so if the parser doesn't set this flag,
4969  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4970  * will be used.
4971  */
4973 
4974 #if FF_API_CONVERGENCE_DURATION
4975  /**
4976  * @deprecated unused
4977  */
4980 #endif
4981 
4982  // Timestamp generation support:
4983  /**
4984  * Synchronization point for start of timestamp generation.
4985  *
4986  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4987  * (default).
4988  *
4989  * For example, this corresponds to presence of H.264 buffering period
4990  * SEI message.
4991  */
4993 
4994  /**
4995  * Offset of the current timestamp against last timestamp sync point in
4996  * units of AVCodecContext.time_base.
4997  *
4998  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4999  * contain a valid timestamp offset.
5000  *
5001  * Note that the timestamp of sync point has usually a nonzero
5002  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5003  * the next frame after timestamp sync point will be usually 1.
5004  *
5005  * For example, this corresponds to H.264 cpb_removal_delay.
5006  */
5008 
5009  /**
5010  * Presentation delay of current frame in units of AVCodecContext.time_base.
5011  *
5012  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5013  * contain valid non-negative timestamp delta (presentation time of a frame
5014  * must not lie in the past).
5015  *
5016  * This delay represents the difference between decoding and presentation
5017  * time of the frame.
5018  *
5019  * For example, this corresponds to H.264 dpb_output_delay.
5020  */
5022 
5023  /**
5024  * Position of the packet in file.
5025  *
5026  * Analogous to cur_frame_pts/dts
5027  */
5029 
5030  /**
5031  * Byte position of currently parsed frame in stream.
5032  */
5033  int64_t pos;
5034 
5035  /**
5036  * Previous frame byte position.
5037  */
5038  int64_t last_pos;
5039 
5040  /**
5041  * Duration of the current frame.
5042  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5043  * For all other types, this is in units of AVCodecContext.time_base.
5044  */
5046 
5048 
5049  /**
5050  * Indicate whether a picture is coded as a frame, top field or bottom field.
5051  *
5052  * For example, H.264 field_pic_flag equal to 0 corresponds to
5053  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5054  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5055  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5056  */
5058 
5059  /**
5060  * Picture number incremented in presentation or output order.
5061  * This field may be reinitialized at the first picture of a new sequence.
5062  *
5063  * For example, this corresponds to H.264 PicOrderCnt.
5064  */
5066 
5067  /**
5068  * Dimensions of the decoded video intended for presentation.
5069  */
5070  int width;
5071  int height;
5072 
5073  /**
5074  * Dimensions of the coded video.
5075  */
5078 
5079  /**
5080  * The format of the coded data, corresponds to enum AVPixelFormat for video
5081  * and for enum AVSampleFormat for audio.
5082  *
5083  * Note that a decoder can have considerable freedom in how exactly it
5084  * decodes the data, so the format reported here might be different from the
5085  * one returned by a decoder.
5086  */
5087  int format;
5089 
5090 typedef struct AVCodecParser {
5091  int codec_ids[5]; /* several codec IDs are permitted */
5094  /* This callback never returns an error, a negative value means that
5095  * the frame start was in a previous packet. */
5097  AVCodecContext *avctx,
5098  const uint8_t **poutbuf, int *poutbuf_size,
5099  const uint8_t *buf, int buf_size);
5101  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5103 } AVCodecParser;
5104 
5106 
5109 
5110 /**
5111  * Parse a packet.
5112  *
5113  * @param s parser context.
5114  * @param avctx codec context.
5115  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5116  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5117  * @param buf input buffer.
5118  * @param buf_size input length, to signal EOF, this should be 0 (so that the last frame can be output).
5119  * @param pts input presentation timestamp.
5120  * @param dts input decoding timestamp.
5121  * @param pos input byte position in stream.
5122  * @return the number of bytes of the input bitstream used.
5123  *
5124  * Example:
5125  * @code
5126  * while(in_len){
5127  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5128  * in_data, in_len,
5129  * pts, dts, pos);
5130  * in_data += len;
5131  * in_len -= len;
5132  *
5133  * if(size)
5134  * decode_frame(data, size);
5135  * }
5136  * @endcode
5137  */
5139  AVCodecContext *avctx,
5140  uint8_t **poutbuf, int *poutbuf_size,
5141  const uint8_t *buf, int buf_size,
5142  int64_t pts, int64_t dts,
5143  int64_t pos);
5144 
5145 /**
5146  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5147  * @deprecated use AVBitStreamFilter
5148  */
5150  AVCodecContext *avctx,
5151  uint8_t **poutbuf, int *poutbuf_size,
5152  const uint8_t *buf, int buf_size, int keyframe);
5154 
5155 /**
5156  * @}
5157  * @}
5158  */
5159 
5160 /**
5161  * @addtogroup lavc_encoding
5162  * @{
5163  */
5164 
5165 /**
5166  * Find a registered encoder with a matching codec ID.
5167  *
5168  * @param id AVCodecID of the requested encoder
5169  * @return An encoder if one was found, NULL otherwise.
5170  */
5172 
5173 /**
5174  * Find a registered encoder with the specified name.
5175  *
5176  * @param name name of the requested encoder
5177  * @return An encoder if one was found, NULL otherwise.
5178  */
5180 
5181 /**
5182  * Encode a frame of audio.
5183  *
5184  * Takes input samples from frame and writes the next output packet, if
5185  * available, to avpkt. The output packet does not necessarily contain data for
5186  * the most recent frame, as encoders can delay, split, and combine input frames
5187  * internally as needed.
5188  *
5189  * @param avctx codec context
5190  * @param avpkt output AVPacket.
5191  * The user can supply an output buffer by setting
5192  * avpkt->data and avpkt->size prior to calling the
5193  * function, but if the size of the user-provided data is not
5194  * large enough, encoding will fail. If avpkt->data and
5195  * avpkt->size are set, avpkt->destruct must also be set. All
5196  * other AVPacket fields will be reset by the encoder using
5197  * av_init_packet(). If avpkt->data is NULL, the encoder will
5198  * allocate it. The encoder will set avpkt->size to the size
5199  * of the output packet.
5200  *
5201  * If this function fails or produces no output, avpkt will be
5202  * freed using av_packet_unref().
5203  * @param[in] frame AVFrame containing the raw audio data to be encoded.
5204  * May be NULL when flushing an encoder that has the
5205  * AV_CODEC_CAP_DELAY capability set.
5206  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5207  * can have any number of samples.
5208  * If it is not set, frame->nb_samples must be equal to
5209  * avctx->frame_size for all frames except the last.
5210  * The final frame may be smaller than avctx->frame_size.
5211  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5212  * output packet is non-empty, and to 0 if it is
5213  * empty. If the function returns an error, the
5214  * packet can be assumed to be invalid, and the
5215  * value of got_packet_ptr is undefined and should
5216  * not be used.
5217  * @return 0 on success, negative error code on failure
5218  *
5219  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5220  */
5222 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5223  const AVFrame *frame, int *got_packet_ptr);
5224 
5225 /**
5226  * Encode a frame of video.
5227  *
5228  * Takes input raw video data from frame and writes the next output packet, if
5229  * available, to avpkt. The output packet does not necessarily contain data for
5230  * the most recent frame, as encoders can delay and reorder input frames
5231  * internally as needed.
5232  *
5233  * @param avctx codec context
5234  * @param avpkt output AVPacket.
5235  * The user can supply an output buffer by setting
5236  * avpkt->data and avpkt->size prior to calling the
5237  * function, but if the size of the user-provided data is not
5238  * large enough, encoding will fail. All other AVPacket fields
5239  * will be reset by the encoder using av_init_packet(). If
5240  * avpkt->data is NULL, the encoder will allocate it.
5241  * The encoder will set avpkt->size to the size of the
5242  * output packet. The returned data (if any) belongs to the
5243  * caller, he is responsible for freeing it.
5244  *
5245  * If this function fails or produces no output, avpkt will be
5246  * freed using av_packet_unref().
5247  * @param[in] frame AVFrame containing the raw video data to be encoded.
5248  * May be NULL when flushing an encoder that has the
5249  * AV_CODEC_CAP_DELAY capability set.
5250  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5251  * output packet is non-empty, and to 0 if it is
5252  * empty. If the function returns an error, the
5253  * packet can be assumed to be invalid, and the
5254  * value of got_packet_ptr is undefined and should
5255  * not be used.
5256  * @return 0 on success, negative error code on failure
5257  *
5258  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5259  */
5261 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
5262  const AVFrame *frame, int *got_packet_ptr);
5263 
5264 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
5265  const AVSubtitle *sub);
5266 
5267 
5268 /**
5269  * @}
5270  */
5271 
5272 #if FF_API_AVCODEC_RESAMPLE
5273 /**
5274  * @defgroup lavc_resample Audio resampling
5275  * @ingroup libavc
5276  * @deprecated use libswresample instead
5277  *
5278  * @{
5279  */
5280 struct ReSampleContext;
5281 struct AVResampleContext;
5282 
5283 typedef struct ReSampleContext ReSampleContext;
5284 
5285 /**
5286  * Initialize audio resampling context.
5287  *
5288  * @param output_channels number of output channels
5289  * @param input_channels number of input channels
5290  * @param output_rate output sample rate
5291  * @param input_rate input sample rate
5292  * @param sample_fmt_out requested output sample format
5293  * @param sample_fmt_in input sample format
5294  * @param filter_length length of each FIR filter in the filterbank relative to the cutoff frequency
5295  * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
5296  * @param linear if 1 then the used FIR filter will be linearly interpolated
5297  between the 2 closest, if 0 the closest will be used
5298  * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
5299  * @return allocated ReSampleContext, NULL if error occurred
5300  */
5303  int output_rate, int input_rate,
5304  enum AVSampleFormat sample_fmt_out,
5305  enum AVSampleFormat sample_fmt_in,
5306  int filter_length, int log2_phase_count,
5307  int linear, double cutoff);
5308 
5310 int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
5311 
5312 /**
5313  * Free resample context.
5314  *
5315  * @param s a non-NULL pointer to a resample context previously
5316  * created with av_audio_resample_init()
5317  */
5320 
5321 
5322 /**
5323  * Initialize an audio resampler.
5324  * Note, if either rate is not an integer then simply scale both rates up so they are.
5325  * @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
5326  * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
5327  * @param linear If 1 then the used FIR filter will be linearly interpolated
5328  between the 2 closest, if 0 the closest will be used
5329  * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate