FFmpeg
avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include "libavutil/samplefmt.h"
31 #include "libavutil/attributes.h"
32 #include "libavutil/avutil.h"
33 #include "libavutil/buffer.h"
35 #include "libavutil/dict.h"
36 #include "libavutil/frame.h"
37 #include "libavutil/log.h"
38 #include "libavutil/pixfmt.h"
39 #include "libavutil/rational.h"
40 
41 #include "codec.h"
42 #include "codec_id.h"
43 #include "defs.h"
44 #include "packet.h"
45 #include "version_major.h"
46 #ifndef HAVE_AV_CONFIG_H
47 /* When included as part of the ffmpeg build, only include the major version
48  * to avoid unnecessary rebuilds. When included externally, keep including
49  * the full version information. */
50 #include "version.h"
51 
52 #include "codec_desc.h"
53 #include "codec_par.h"
54 #endif
55 
56 struct AVCodecParameters;
57 
58 /**
59  * @defgroup libavc libavcodec
60  * Encoding/Decoding Library
61  *
62  * @{
63  *
64  * @defgroup lavc_decoding Decoding
65  * @{
66  * @}
67  *
68  * @defgroup lavc_encoding Encoding
69  * @{
70  * @}
71  *
72  * @defgroup lavc_codec Codecs
73  * @{
74  * @defgroup lavc_codec_native Native Codecs
75  * @{
76  * @}
77  * @defgroup lavc_codec_wrappers External library wrappers
78  * @{
79  * @}
80  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
81  * @{
82  * @}
83  * @}
84  * @defgroup lavc_internal Internal
85  * @{
86  * @}
87  * @}
88  */
89 
90 /**
91  * @ingroup libavc
92  * @defgroup lavc_encdec send/receive encoding and decoding API overview
93  * @{
94  *
95  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
96  * avcodec_receive_packet() functions provide an encode/decode API, which
97  * decouples input and output.
98  *
99  * The API is very similar for encoding/decoding and audio/video, and works as
100  * follows:
101  * - Set up and open the AVCodecContext as usual.
102  * - Send valid input:
103  * - For decoding, call avcodec_send_packet() to give the decoder raw
104  * compressed data in an AVPacket.
105  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
106  * containing uncompressed audio or video.
107  *
108  * In both cases, it is recommended that AVPackets and AVFrames are
109  * refcounted, or libavcodec might have to copy the input data. (libavformat
110  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
111  * refcounted AVFrames.)
112  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
113  * functions and process their output:
114  * - For decoding, call avcodec_receive_frame(). On success, it will return
115  * an AVFrame containing uncompressed audio or video data.
116  * - For encoding, call avcodec_receive_packet(). On success, it will return
117  * an AVPacket with a compressed frame.
118  *
119  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
120  * AVERROR(EAGAIN) return value means that new input data is required to
121  * return new output. In this case, continue with sending input. For each
122  * input frame/packet, the codec will typically return 1 output frame/packet,
123  * but it can also be 0 or more than 1.
124  *
125  * At the beginning of decoding or encoding, the codec might accept multiple
126  * input frames/packets without returning a frame, until its internal buffers
127  * are filled. This situation is handled transparently if you follow the steps
128  * outlined above.
129  *
130  * In theory, sending input can result in EAGAIN - this should happen only if
131  * not all output was received. You can use this to structure alternative decode
132  * or encode loops other than the one suggested above. For example, you could
133  * try sending new input on each iteration, and try to receive output if that
134  * returns EAGAIN.
135  *
136  * End of stream situations. These require "flushing" (aka draining) the codec,
137  * as the codec might buffer multiple frames or packets internally for
138  * performance or out of necessity (consider B-frames).
139  * This is handled as follows:
140  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
141  * or avcodec_send_frame() (encoding) functions. This will enter draining
142  * mode.
143  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
144  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
145  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
146  * - Before decoding can be resumed again, the codec has to be reset with
147  * avcodec_flush_buffers().
148  *
149  * Using the API as outlined above is highly recommended. But it is also
150  * possible to call functions outside of this rigid schema. For example, you can
151  * call avcodec_send_packet() repeatedly without calling
152  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
153  * until the codec's internal buffer has been filled up (which is typically of
154  * size 1 per output frame, after initial input), and then reject input with
155  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
156  * read at least some output.
157  *
158  * Not all codecs will follow a rigid and predictable dataflow; the only
159  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
160  * one end implies that a receive/send call on the other end will succeed, or
161  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
162  * permit unlimited buffering of input or output.
163  *
164  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
165  * would be an invalid state, which could put the codec user into an endless
166  * loop. The API has no concept of time either: it cannot happen that trying to
167  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
168  * later accepts the packet (with no other receive/flush API calls involved).
169  * The API is a strict state machine, and the passage of time is not supposed
170  * to influence it. Some timing-dependent behavior might still be deemed
171  * acceptable in certain cases. But it must never result in both send/receive
172  * returning EAGAIN at the same time at any point. It must also absolutely be
173  * avoided that the current state is "unstable" and can "flip-flop" between
174  * the send/receive APIs allowing progress. For example, it's not allowed that
175  * the codec randomly decides that it actually wants to consume a packet now
176  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
177  * avcodec_send_packet() call.
178  * @}
179  */
180 
181 /**
182  * @defgroup lavc_core Core functions/structures.
183  * @ingroup libavc
184  *
185  * Basic definitions, functions for querying libavcodec capabilities,
186  * allocating core structures, etc.
187  * @{
188  */
189 
190 #if FF_API_BUFFER_MIN_SIZE
191 /**
192  * @ingroup lavc_encoding
193  * minimum encoding buffer size
194  * Used to avoid some checks during header writing.
195  * @deprecated Unused: avcodec_receive_packet() does not work
196  * with preallocated packet buffers.
197  */
198 #define AV_INPUT_BUFFER_MIN_SIZE 16384
199 #endif
200 
201 /**
202  * @ingroup lavc_encoding
203  */
204 typedef struct RcOverride{
207  int qscale; // If this is 0 then quality_factor will be used instead.
209 } RcOverride;
210 
211 /* encoding support
212  These flags can be passed in AVCodecContext.flags before initialization.
213  Note: Not everything is supported yet.
214 */
215 
216 /**
217  * Allow decoders to produce frames with data planes that are not aligned
218  * to CPU requirements (e.g. due to cropping).
219  */
220 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
221 /**
222  * Use fixed qscale.
223  */
224 #define AV_CODEC_FLAG_QSCALE (1 << 1)
225 /**
226  * 4 MV per MB allowed / advanced prediction for H.263.
227  */
228 #define AV_CODEC_FLAG_4MV (1 << 2)
229 /**
230  * Output even those frames that might be corrupted.
231  */
232 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
233 /**
234  * Use qpel MC.
235  */
236 #define AV_CODEC_FLAG_QPEL (1 << 4)
237 #if FF_API_DROPCHANGED
238 /**
239  * Don't output frames whose parameters differ from first
240  * decoded frame in stream.
241  *
242  * @deprecated callers should implement this functionality in their own code
243  */
244 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
245 #endif
246 /**
247  * Request the encoder to output reconstructed frames, i.e.\ frames that would
248  * be produced by decoding the encoded bistream. These frames may be retrieved
249  * by calling avcodec_receive_frame() immediately after a successful call to
250  * avcodec_receive_packet().
251  *
252  * Should only be used with encoders flagged with the
253  * @ref AV_CODEC_CAP_ENCODER_RECON_FRAME capability.
254  *
255  * @note
256  * Each reconstructed frame returned by the encoder corresponds to the last
257  * encoded packet, i.e. the frames are returned in coded order rather than
258  * presentation order.
259  *
260  * @note
261  * Frame parameters (like pixel format or dimensions) do not have to match the
262  * AVCodecContext values. Make sure to use the values from the returned frame.
263  */
264 #define AV_CODEC_FLAG_RECON_FRAME (1 << 6)
265 /**
266  * @par decoding
267  * Request the decoder to propagate each packet's AVPacket.opaque and
268  * AVPacket.opaque_ref to its corresponding output AVFrame.
269  *
270  * @par encoding:
271  * Request the encoder to propagate each frame's AVFrame.opaque and
272  * AVFrame.opaque_ref values to its corresponding output AVPacket.
273  *
274  * @par
275  * May only be set on encoders that have the
276  * @ref AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability flag.
277  *
278  * @note
279  * While in typical cases one input frame produces exactly one output packet
280  * (perhaps after a delay), in general the mapping of frames to packets is
281  * M-to-N, so
282  * - Any number of input frames may be associated with any given output packet.
283  * This includes zero - e.g. some encoders may output packets that carry only
284  * metadata about the whole stream.
285  * - A given input frame may be associated with any number of output packets.
286  * Again this includes zero - e.g. some encoders may drop frames under certain
287  * conditions.
288  * .
289  * This implies that when using this flag, the caller must NOT assume that
290  * - a given input frame's opaques will necessarily appear on some output packet;
291  * - every output packet will have some non-NULL opaque value.
292  * .
293  * When an output packet contains multiple frames, the opaque values will be
294  * taken from the first of those.
295  *
296  * @note
297  * The converse holds for decoders, with frames and packets switched.
298  */
299 #define AV_CODEC_FLAG_COPY_OPAQUE (1 << 7)
300 /**
301  * Signal to the encoder that the values of AVFrame.duration are valid and
302  * should be used (typically for transferring them to output packets).
303  *
304  * If this flag is not set, frame durations are ignored.
305  */
306 #define AV_CODEC_FLAG_FRAME_DURATION (1 << 8)
307 /**
308  * Use internal 2pass ratecontrol in first pass mode.
309  */
310 #define AV_CODEC_FLAG_PASS1 (1 << 9)
311 /**
312  * Use internal 2pass ratecontrol in second pass mode.
313  */
314 #define AV_CODEC_FLAG_PASS2 (1 << 10)
315 /**
316  * loop filter.
317  */
318 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
319 /**
320  * Only decode/encode grayscale.
321  */
322 #define AV_CODEC_FLAG_GRAY (1 << 13)
323 /**
324  * error[?] variables will be set during encoding.
325  */
326 #define AV_CODEC_FLAG_PSNR (1 << 15)
327 /**
328  * Use interlaced DCT.
329  */
330 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
331 /**
332  * Force low delay.
333  */
334 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
335 /**
336  * Place global headers in extradata instead of every keyframe.
337  */
338 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
339 /**
340  * Use only bitexact stuff (except (I)DCT).
341  */
342 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
343 /* Fx : Flag for H.263+ extra options */
344 /**
345  * H.263 advanced intra coding / MPEG-4 AC prediction
346  */
347 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
348 /**
349  * interlaced motion estimation
350  */
351 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
352 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
353 
354 /**
355  * Allow non spec compliant speedup tricks.
356  */
357 #define AV_CODEC_FLAG2_FAST (1 << 0)
358 /**
359  * Skip bitstream encoding.
360  */
361 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
362 /**
363  * Place global headers at every keyframe instead of in extradata.
364  */
365 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
366 
367 /**
368  * Input bitstream might be truncated at a packet boundaries
369  * instead of only at frame boundaries.
370  */
371 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
372 /**
373  * Discard cropping information from SPS.
374  */
375 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
376 
377 /**
378  * Show all frames before the first keyframe
379  */
380 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
381 /**
382  * Export motion vectors through frame side data
383  */
384 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
385 /**
386  * Do not skip samples and export skip information as frame side data
387  */
388 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
389 /**
390  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
391  */
392 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
393 /**
394  * Generate/parse ICC profiles on encode/decode, as appropriate for the type of
395  * file. No effect on codecs which cannot contain embedded ICC profiles, or
396  * when compiled without support for lcms2.
397  */
398 #define AV_CODEC_FLAG2_ICC_PROFILES (1U << 31)
399 
400 /* Exported side data.
401  These flags can be passed in AVCodecContext.export_side_data before initialization.
402 */
403 /**
404  * Export motion vectors through frame side data
405  */
406 #define AV_CODEC_EXPORT_DATA_MVS (1 << 0)
407 /**
408  * Export encoder Producer Reference Time through packet side data
409  */
410 #define AV_CODEC_EXPORT_DATA_PRFT (1 << 1)
411 /**
412  * Decoding only.
413  * Export the AVVideoEncParams structure through frame side data.
414  */
415 #define AV_CODEC_EXPORT_DATA_VIDEO_ENC_PARAMS (1 << 2)
416 /**
417  * Decoding only.
418  * Do not apply film grain, export it instead.
419  */
420 #define AV_CODEC_EXPORT_DATA_FILM_GRAIN (1 << 3)
421 
422 /**
423  * The decoder will keep a reference to the frame and may reuse it later.
424  */
425 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
426 
427 /**
428  * The encoder will keep a reference to the packet and may reuse it later.
429  */
430 #define AV_GET_ENCODE_BUFFER_FLAG_REF (1 << 0)
431 
432 /**
433  * main external API structure.
434  * New fields can be added to the end with minor version bumps.
435  * Removal, reordering and changes to existing fields require a major
436  * version bump.
437  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
438  * applications.
439  * The name string for AVOptions options matches the associated command line
440  * parameter name and can be found in libavcodec/options_table.h
441  * The AVOption/command line parameter names differ in some cases from the C
442  * structure field names for historic reasons or brevity.
443  * sizeof(AVCodecContext) must not be used outside libav*.
444  */
445 typedef struct AVCodecContext {
446  /**
447  * information on struct for av_log
448  * - set by avcodec_alloc_context3
449  */
452 
453  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
454  const struct AVCodec *codec;
455  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
456 
457  /**
458  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
459  * This is used to work around some encoder bugs.
460  * A demuxer should set this to what is stored in the field used to identify the codec.
461  * If there are multiple such fields in a container then the demuxer should choose the one
462  * which maximizes the information about the used codec.
463  * If the codec tag field in a container is larger than 32 bits then the demuxer should
464  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
465  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
466  * first.
467  * - encoding: Set by user, if not then the default based on codec_id will be used.
468  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
469  */
470  unsigned int codec_tag;
471 
472  void *priv_data;
473 
474  /**
475  * Private context used for internal data.
476  *
477  * Unlike priv_data, this is not codec-specific. It is used in general
478  * libavcodec functions.
479  */
480  struct AVCodecInternal *internal;
481 
482  /**
483  * Private data of the user, can be used to carry app specific stuff.
484  * - encoding: Set by user.
485  * - decoding: Set by user.
486  */
487  void *opaque;
488 
489  /**
490  * the average bitrate
491  * - encoding: Set by user; unused for constant quantizer encoding.
492  * - decoding: Set by user, may be overwritten by libavcodec
493  * if this info is available in the stream
494  */
495  int64_t bit_rate;
496 
497  /**
498  * AV_CODEC_FLAG_*.
499  * - encoding: Set by user.
500  * - decoding: Set by user.
501  */
502  int flags;
503 
504  /**
505  * AV_CODEC_FLAG2_*
506  * - encoding: Set by user.
507  * - decoding: Set by user.
508  */
509  int flags2;
510 
511  /**
512  * some codecs need / can use extradata like Huffman tables.
513  * MJPEG: Huffman tables
514  * rv10: additional flags
515  * MPEG-4: global headers (they can be in the bitstream or here)
516  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
517  * than extradata_size to avoid problems if it is read with the bitstream reader.
518  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
519  * Must be allocated with the av_malloc() family of functions.
520  * - encoding: Set/allocated/freed by libavcodec.
521  * - decoding: Set/allocated/freed by user.
522  */
523  uint8_t *extradata;
525 
526  /**
527  * This is the fundamental unit of time (in seconds) in terms
528  * of which frame timestamps are represented. For fixed-fps content,
529  * timebase should be 1/framerate and timestamp increments should be
530  * identically 1.
531  * This often, but not always is the inverse of the frame rate or field rate
532  * for video. 1/time_base is not the average frame rate if the frame rate is not
533  * constant.
534  *
535  * Like containers, elementary streams also can store timestamps, 1/time_base
536  * is the unit in which these timestamps are specified.
537  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
538  * vop_time_increment_resolution and fixed_vop_rate
539  * (fixed_vop_rate == 0 implies that it is different from the framerate)
540  *
541  * - encoding: MUST be set by user.
542  * - decoding: unused.
543  */
545 
546  /**
547  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
548  * - encoding: unused.
549  * - decoding: set by user.
550  */
552 
553  /**
554  * - decoding: For codecs that store a framerate value in the compressed
555  * bitstream, the decoder may export it here. { 0, 1} when
556  * unknown.
557  * - encoding: May be used to signal the framerate of CFR content to an
558  * encoder.
559  */
561 
562 #if FF_API_TICKS_PER_FRAME
563  /**
564  * For some codecs, the time base is closer to the field rate than the frame rate.
565  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
566  * if no telecine is used ...
567  *
568  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
569  *
570  * @deprecated
571  * - decoding: Use AVCodecDescriptor.props & AV_CODEC_PROP_FIELDS
572  * - encoding: Set AVCodecContext.framerate instead
573  *
574  */
577 #endif
578 
579  /**
580  * Codec delay.
581  *
582  * Encoding: Number of frames delay there will be from the encoder input to
583  * the decoder output. (we assume the decoder matches the spec)
584  * Decoding: Number of frames delay in addition to what a standard decoder
585  * as specified in the spec would produce.
586  *
587  * Video:
588  * Number of frames the decoded output will be delayed relative to the
589  * encoded input.
590  *
591  * Audio:
592  * For encoding, this field is unused (see initial_padding).
593  *
594  * For decoding, this is the number of samples the decoder needs to
595  * output before the decoder's output is valid. When seeking, you should
596  * start decoding this many samples prior to your desired seek point.
597  *
598  * - encoding: Set by libavcodec.
599  * - decoding: Set by libavcodec.
600  */
601  int delay;
602 
603 
604  /* video only */
605  /**
606  * picture width / height.
607  *
608  * @note Those fields may not match the values of the last
609  * AVFrame output by avcodec_receive_frame() due frame
610  * reordering.
611  *
612  * - encoding: MUST be set by user.
613  * - decoding: May be set by the user before opening the decoder if known e.g.
614  * from the container. Some decoders will require the dimensions
615  * to be set by the caller. During decoding, the decoder may
616  * overwrite those values as required while parsing the data.
617  */
618  int width, height;
619 
620  /**
621  * Bitstream width / height, may be different from width/height e.g. when
622  * the decoded frame is cropped before being output or lowres is enabled.
623  *
624  * @note Those field may not match the value of the last
625  * AVFrame output by avcodec_receive_frame() due frame
626  * reordering.
627  *
628  * - encoding: unused
629  * - decoding: May be set by the user before opening the decoder if known
630  * e.g. from the container. During decoding, the decoder may
631  * overwrite those values as required while parsing the data.
632  */
634 
635  /**
636  * sample aspect ratio (0 if unknown)
637  * That is the width of a pixel divided by the height of the pixel.
638  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
639  * - encoding: Set by user.
640  * - decoding: Set by libavcodec.
641  */
643 
644  /**
645  * Pixel format, see AV_PIX_FMT_xxx.
646  * May be set by the demuxer if known from headers.
647  * May be overridden by the decoder if it knows better.
648  *
649  * @note This field may not match the value of the last
650  * AVFrame output by avcodec_receive_frame() due frame
651  * reordering.
652  *
653  * - encoding: Set by user.
654  * - decoding: Set by user if known, overridden by libavcodec while
655  * parsing the data.
656  */
658 
659  /**
660  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
661  * - encoding: unused.
662  * - decoding: Set by libavcodec before calling get_format()
663  */
665 
666  /**
667  * Chromaticity coordinates of the source primaries.
668  * - encoding: Set by user
669  * - decoding: Set by libavcodec
670  */
672 
673  /**
674  * Color Transfer Characteristic.
675  * - encoding: Set by user
676  * - decoding: Set by libavcodec
677  */
679 
680  /**
681  * YUV colorspace type.
682  * - encoding: Set by user
683  * - decoding: Set by libavcodec
684  */
686 
687  /**
688  * MPEG vs JPEG YUV range.
689  * - encoding: Set by user to override the default output color range value,
690  * If not specified, libavcodec sets the color range depending on the
691  * output format.
692  * - decoding: Set by libavcodec, can be set by the user to propagate the
693  * color range to components reading from the decoder context.
694  */
696 
697  /**
698  * This defines the location of chroma samples.
699  * - encoding: Set by user
700  * - decoding: Set by libavcodec
701  */
703 
704  /** Field order
705  * - encoding: set by libavcodec
706  * - decoding: Set by user.
707  */
709 
710  /**
711  * number of reference frames
712  * - encoding: Set by user.
713  * - decoding: Set by lavc.
714  */
715  int refs;
716 
717  /**
718  * Size of the frame reordering buffer in the decoder.
719  * For MPEG-2 it is 1 IPB or 0 low delay IP.
720  * - encoding: Set by libavcodec.
721  * - decoding: Set by libavcodec.
722  */
724 
725  /**
726  * slice flags
727  * - encoding: unused
728  * - decoding: Set by user.
729  */
731 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
732 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
733 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
734 
735  /**
736  * If non NULL, 'draw_horiz_band' is called by the libavcodec
737  * decoder to draw a horizontal band. It improves cache usage. Not
738  * all codecs can do that. You must check the codec capabilities
739  * beforehand.
740  * When multithreading is used, it may be called from multiple threads
741  * at the same time; threads might draw different parts of the same AVFrame,
742  * or multiple AVFrames, and there is no guarantee that slices will be drawn
743  * in order.
744  * The function is also used by hardware acceleration APIs.
745  * It is called at least once during frame decoding to pass
746  * the data needed for hardware render.
747  * In that mode instead of pixel data, AVFrame points to
748  * a structure specific to the acceleration API. The application
749  * reads the structure and can change some fields to indicate progress
750  * or mark state.
751  * - encoding: unused
752  * - decoding: Set by user.
753  * @param height the height of the slice
754  * @param y the y position of the slice
755  * @param type 1->top field, 2->bottom field, 3->frame
756  * @param offset offset into the AVFrame.data from which the slice should be read
757  */
759  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
760  int y, int type, int height);
761 
762  /**
763  * Callback to negotiate the pixel format. Decoding only, may be set by the
764  * caller before avcodec_open2().
765  *
766  * Called by some decoders to select the pixel format that will be used for
767  * the output frames. This is mainly used to set up hardware acceleration,
768  * then the provided format list contains the corresponding hwaccel pixel
769  * formats alongside the "software" one. The software pixel format may also
770  * be retrieved from \ref sw_pix_fmt.
771  *
772  * This callback will be called when the coded frame properties (such as
773  * resolution, pixel format, etc.) change and more than one output format is
774  * supported for those new properties. If a hardware pixel format is chosen
775  * and initialization for it fails, the callback may be called again
776  * immediately.
777  *
778  * This callback may be called from different threads if the decoder is
779  * multi-threaded, but not from more than one thread simultaneously.
780  *
781  * @param fmt list of formats which may be used in the current
782  * configuration, terminated by AV_PIX_FMT_NONE.
783  * @warning Behavior is undefined if the callback returns a value other
784  * than one of the formats in fmt or AV_PIX_FMT_NONE.
785  * @return the chosen format or AV_PIX_FMT_NONE
786  */
787  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
788 
789  /**
790  * maximum number of B-frames between non-B-frames
791  * Note: The output will be delayed by max_b_frames+1 relative to the input.
792  * - encoding: Set by user.
793  * - decoding: unused
794  */
796 
797  /**
798  * qscale factor between IP and B-frames
799  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
800  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
801  * - encoding: Set by user.
802  * - decoding: unused
803  */
805 
806  /**
807  * qscale offset between IP and B-frames
808  * - encoding: Set by user.
809  * - decoding: unused
810  */
812 
813  /**
814  * qscale factor between P- and I-frames
815  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
816  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
817  * - encoding: Set by user.
818  * - decoding: unused
819  */
821 
822  /**
823  * qscale offset between P and I-frames
824  * - encoding: Set by user.
825  * - decoding: unused
826  */
828 
829  /**
830  * luminance masking (0-> disabled)
831  * - encoding: Set by user.
832  * - decoding: unused
833  */
835 
836  /**
837  * temporary complexity masking (0-> disabled)
838  * - encoding: Set by user.
839  * - decoding: unused
840  */
842 
843  /**
844  * spatial complexity masking (0-> disabled)
845  * - encoding: Set by user.
846  * - decoding: unused
847  */
849 
850  /**
851  * p block masking (0-> disabled)
852  * - encoding: Set by user.
853  * - decoding: unused
854  */
855  float p_masking;
856 
857  /**
858  * darkness masking (0-> disabled)
859  * - encoding: Set by user.
860  * - decoding: unused
861  */
863 
864  /**
865  * noise vs. sse weight for the nsse comparison function
866  * - encoding: Set by user.
867  * - decoding: unused
868  */
870 
871  /**
872  * motion estimation comparison function
873  * - encoding: Set by user.
874  * - decoding: unused
875  */
876  int me_cmp;
877  /**
878  * subpixel motion estimation comparison function
879  * - encoding: Set by user.
880  * - decoding: unused
881  */
883  /**
884  * macroblock comparison function (not supported yet)
885  * - encoding: Set by user.
886  * - decoding: unused
887  */
888  int mb_cmp;
889  /**
890  * interlaced DCT comparison function
891  * - encoding: Set by user.
892  * - decoding: unused
893  */
895 #define FF_CMP_SAD 0
896 #define FF_CMP_SSE 1
897 #define FF_CMP_SATD 2
898 #define FF_CMP_DCT 3
899 #define FF_CMP_PSNR 4
900 #define FF_CMP_BIT 5
901 #define FF_CMP_RD 6
902 #define FF_CMP_ZERO 7
903 #define FF_CMP_VSAD 8
904 #define FF_CMP_VSSE 9
905 #define FF_CMP_NSSE 10
906 #define FF_CMP_W53 11
907 #define FF_CMP_W97 12
908 #define FF_CMP_DCTMAX 13
909 #define FF_CMP_DCT264 14
910 #define FF_CMP_MEDIAN_SAD 15
911 #define FF_CMP_CHROMA 256
912 
913  /**
914  * ME diamond size & shape
915  * - encoding: Set by user.
916  * - decoding: unused
917  */
918  int dia_size;
919 
920  /**
921  * amount of previous MV predictors (2a+1 x 2a+1 square)
922  * - encoding: Set by user.
923  * - decoding: unused
924  */
926 
927  /**
928  * motion estimation prepass comparison function
929  * - encoding: Set by user.
930  * - decoding: unused
931  */
933 
934  /**
935  * ME prepass diamond size & shape
936  * - encoding: Set by user.
937  * - decoding: unused
938  */
940 
941  /**
942  * subpel ME quality
943  * - encoding: Set by user.
944  * - decoding: unused
945  */
947 
948  /**
949  * maximum motion estimation search range in subpel units
950  * If 0 then no limit.
951  *
952  * - encoding: Set by user.
953  * - decoding: unused
954  */
955  int me_range;
956 
957  /**
958  * macroblock decision mode
959  * - encoding: Set by user.
960  * - decoding: unused
961  */
963 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
964 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
965 #define FF_MB_DECISION_RD 2 ///< rate distortion
966 
967  /**
968  * custom intra quantization matrix
969  * Must be allocated with the av_malloc() family of functions, and will be freed in
970  * avcodec_free_context().
971  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
972  * - decoding: Set/allocated/freed by libavcodec.
973  */
974  uint16_t *intra_matrix;
975 
976  /**
977  * custom inter quantization matrix
978  * Must be allocated with the av_malloc() family of functions, and will be freed in
979  * avcodec_free_context().
980  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
981  * - decoding: Set/allocated/freed by libavcodec.
982  */
983  uint16_t *inter_matrix;
984 
985  /**
986  * custom intra quantization matrix
987  * - encoding: Set by user, can be NULL.
988  * - decoding: unused.
989  */
991 
992  /**
993  * precision of the intra DC coefficient - 8
994  * - encoding: Set by user.
995  * - decoding: Set by libavcodec
996  */
998 
999  /**
1000  * minimum MB Lagrange multiplier
1001  * - encoding: Set by user.
1002  * - decoding: unused
1003  */
1004  int mb_lmin;
1005 
1006  /**
1007  * maximum MB Lagrange multiplier
1008  * - encoding: Set by user.
1009  * - decoding: unused
1010  */
1011  int mb_lmax;
1012 
1013  /**
1014  * - encoding: Set by user.
1015  * - decoding: unused
1016  */
1018 
1019  /**
1020  * minimum GOP size
1021  * - encoding: Set by user.
1022  * - decoding: unused
1023  */
1025 
1026  /**
1027  * the number of pictures in a group of pictures, or 0 for intra_only
1028  * - encoding: Set by user.
1029  * - decoding: unused
1030  */
1032 
1033  /**
1034  * Note: Value depends upon the compare function used for fullpel ME.
1035  * - encoding: Set by user.
1036  * - decoding: unused
1037  */
1039 
1040  /**
1041  * Number of slices.
1042  * Indicates number of picture subdivisions. Used for parallelized
1043  * decoding.
1044  * - encoding: Set by user
1045  * - decoding: unused
1046  */
1047  int slices;
1048 
1049  /* audio only */
1050  int sample_rate; ///< samples per second
1051 
1052  /**
1053  * audio sample format
1054  * - encoding: Set by user.
1055  * - decoding: Set by libavcodec.
1056  */
1057  enum AVSampleFormat sample_fmt; ///< sample format
1058 
1059  /**
1060  * Audio channel layout.
1061  * - encoding: must be set by the caller, to one of AVCodec.ch_layouts.
1062  * - decoding: may be set by the caller if known e.g. from the container.
1063  * The decoder can then override during decoding as needed.
1064  */
1066 
1067  /* The following data should not be initialized. */
1068  /**
1069  * Number of samples per channel in an audio frame.
1070  *
1071  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1072  * except the last must contain exactly frame_size samples per channel.
1073  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1074  * frame size is not restricted.
1075  * - decoding: may be set by some decoders to indicate constant frame size
1076  */
1078 
1079  /**
1080  * number of bytes per packet if constant and known or 0
1081  * Used by some WAV based audio codecs.
1082  */
1084 
1085  /**
1086  * Audio cutoff bandwidth (0 means "automatic")
1087  * - encoding: Set by user.
1088  * - decoding: unused
1089  */
1090  int cutoff;
1091 
1092  /**
1093  * Type of service that the audio stream conveys.
1094  * - encoding: Set by user.
1095  * - decoding: Set by libavcodec.
1096  */
1098 
1099  /**
1100  * desired sample format
1101  * - encoding: Not used.
1102  * - decoding: Set by user.
1103  * Decoder will decode to this format if it can.
1104  */
1106 
1107  /**
1108  * Audio only. The number of "priming" samples (padding) inserted by the
1109  * encoder at the beginning of the audio. I.e. this number of leading
1110  * decoded samples must be discarded by the caller to get the original audio
1111  * without leading padding.
1112  *
1113  * - decoding: unused
1114  * - encoding: Set by libavcodec. The timestamps on the output packets are
1115  * adjusted by the encoder so that they always refer to the
1116  * first sample of the data actually contained in the packet,
1117  * including any added padding. E.g. if the timebase is
1118  * 1/samplerate and the timestamp of the first input sample is
1119  * 0, the timestamp of the first output packet will be
1120  * -initial_padding.
1121  */
1123 
1124  /**
1125  * Audio only. The amount of padding (in samples) appended by the encoder to
1126  * the end of the audio. I.e. this number of decoded samples must be
1127  * discarded by the caller from the end of the stream to get the original
1128  * audio without any trailing padding.
1129  *
1130  * - decoding: unused
1131  * - encoding: unused
1132  */
1134 
1135  /**
1136  * Number of samples to skip after a discontinuity
1137  * - decoding: unused
1138  * - encoding: set by libavcodec
1139  */
1141 
1142  /**
1143  * This callback is called at the beginning of each frame to get data
1144  * buffer(s) for it. There may be one contiguous buffer for all the data or
1145  * there may be a buffer per each data plane or anything in between. What
1146  * this means is, you may set however many entries in buf[] you feel necessary.
1147  * Each buffer must be reference-counted using the AVBuffer API (see description
1148  * of buf[] below).
1149  *
1150  * The following fields will be set in the frame before this callback is
1151  * called:
1152  * - format
1153  * - width, height (video only)
1154  * - sample_rate, channel_layout, nb_samples (audio only)
1155  * Their values may differ from the corresponding values in
1156  * AVCodecContext. This callback must use the frame values, not the codec
1157  * context values, to calculate the required buffer size.
1158  *
1159  * This callback must fill the following fields in the frame:
1160  * - data[]
1161  * - linesize[]
1162  * - extended_data:
1163  * * if the data is planar audio with more than 8 channels, then this
1164  * callback must allocate and fill extended_data to contain all pointers
1165  * to all data planes. data[] must hold as many pointers as it can.
1166  * extended_data must be allocated with av_malloc() and will be freed in
1167  * av_frame_unref().
1168  * * otherwise extended_data must point to data
1169  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1170  * the frame's data and extended_data pointers must be contained in these. That
1171  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1172  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1173  * and av_buffer_ref().
1174  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1175  * this callback and filled with the extra buffers if there are more
1176  * buffers than buf[] can hold. extended_buf will be freed in
1177  * av_frame_unref().
1178  *
1179  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
1180  * avcodec_default_get_buffer2() instead of providing buffers allocated by
1181  * some other means.
1182  *
1183  * Each data plane must be aligned to the maximum required by the target
1184  * CPU.
1185  *
1186  * @see avcodec_default_get_buffer2()
1187  *
1188  * Video:
1189  *
1190  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
1191  * (read and/or written to if it is writable) later by libavcodec.
1192  *
1193  * avcodec_align_dimensions2() should be used to find the required width and
1194  * height, as they normally need to be rounded up to the next multiple of 16.
1195  *
1196  * Some decoders do not support linesizes changing between frames.
1197  *
1198  * If frame multithreading is used, this callback may be called from a
1199  * different thread, but not from more than one at once. Does not need to be
1200  * reentrant.
1201  *
1202  * @see avcodec_align_dimensions2()
1203  *
1204  * Audio:
1205  *
1206  * Decoders request a buffer of a particular size by setting
1207  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
1208  * however, utilize only part of the buffer by setting AVFrame.nb_samples
1209  * to a smaller value in the output frame.
1210  *
1211  * As a convenience, av_samples_get_buffer_size() and
1212  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
1213  * functions to find the required data size and to fill data pointers and
1214  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1215  * since all planes must be the same size.
1216  *
1217  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1218  *
1219  * - encoding: unused
1220  * - decoding: Set by libavcodec, user can override.
1221  */
1223 
1224  /* - encoding parameters */
1225  /**
1226  * number of bits the bitstream is allowed to diverge from the reference.
1227  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1228  * - encoding: Set by user; unused for constant quantizer encoding.
1229  * - decoding: unused
1230  */
1232 
1233  /**
1234  * Global quality for codecs which cannot change it per frame.
1235  * This should be proportional to MPEG-1/2/4 qscale.
1236  * - encoding: Set by user.
1237  * - decoding: unused
1238  */
1240 
1241  /**
1242  * - encoding: Set by user.
1243  * - decoding: unused
1244  */
1246 #define FF_COMPRESSION_DEFAULT -1
1247 
1248  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
1249  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
1250 
1251  /**
1252  * minimum quantizer
1253  * - encoding: Set by user.
1254  * - decoding: unused
1255  */
1256  int qmin;
1257 
1258  /**
1259  * maximum quantizer
1260  * - encoding: Set by user.
1261  * - decoding: unused
1262  */
1263  int qmax;
1264 
1265  /**
1266  * maximum quantizer difference between frames
1267  * - encoding: Set by user.
1268  * - decoding: unused
1269  */
1271 
1272  /**
1273  * decoder bitstream buffer size
1274  * - encoding: Set by user.
1275  * - decoding: May be set by libavcodec.
1276  */
1278 
1279  /**
1280  * ratecontrol override, see RcOverride
1281  * - encoding: Allocated/set/freed by user.
1282  * - decoding: unused
1283  */
1286 
1287  /**
1288  * maximum bitrate
1289  * - encoding: Set by user.
1290  * - decoding: Set by user, may be overwritten by libavcodec.
1291  */
1292  int64_t rc_max_rate;
1293 
1294  /**
1295  * minimum bitrate
1296  * - encoding: Set by user.
1297  * - decoding: unused
1298  */
1299  int64_t rc_min_rate;
1300 
1301  /**
1302  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
1303  * - encoding: Set by user.
1304  * - decoding: unused.
1305  */
1307 
1308  /**
1309  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
1310  * - encoding: Set by user.
1311  * - decoding: unused.
1312  */
1314 
1315  /**
1316  * Number of bits which should be loaded into the rc buffer before decoding starts.
1317  * - encoding: Set by user.
1318  * - decoding: unused
1319  */
1321 
1322  /**
1323  * trellis RD quantization
1324  * - encoding: Set by user.
1325  * - decoding: unused
1326  */
1327  int trellis;
1328 
1329  /**
1330  * pass1 encoding statistics output buffer
1331  * - encoding: Set by libavcodec.
1332  * - decoding: unused
1333  */
1334  char *stats_out;
1335 
1336  /**
1337  * pass2 encoding statistics input buffer
1338  * Concatenated stuff from stats_out of pass1 should be placed here.
1339  * - encoding: Allocated/set/freed by user.
1340  * - decoding: unused
1341  */
1342  char *stats_in;
1343 
1344  /**
1345  * Work around bugs in encoders which sometimes cannot be detected automatically.
1346  * - encoding: Set by user
1347  * - decoding: Set by user
1348  */
1350 #define FF_BUG_AUTODETECT 1 ///< autodetection
1351 #define FF_BUG_XVID_ILACE 4
1352 #define FF_BUG_UMP4 8
1353 #define FF_BUG_NO_PADDING 16
1354 #define FF_BUG_AMV 32
1355 #define FF_BUG_QPEL_CHROMA 64
1356 #define FF_BUG_STD_QPEL 128
1357 #define FF_BUG_QPEL_CHROMA2 256
1358 #define FF_BUG_DIRECT_BLOCKSIZE 512
1359 #define FF_BUG_EDGE 1024
1360 #define FF_BUG_HPEL_CHROMA 2048
1361 #define FF_BUG_DC_CLIP 4096
1362 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
1363 #define FF_BUG_TRUNCATED 16384
1364 #define FF_BUG_IEDGE 32768
1365 
1366  /**
1367  * strictly follow the standard (MPEG-4, ...).
1368  * - encoding: Set by user.
1369  * - decoding: Set by user.
1370  * Setting this to STRICT or higher means the encoder and decoder will
1371  * generally do stupid things, whereas setting it to unofficial or lower
1372  * will mean the encoder might produce output that is not supported by all
1373  * spec-compliant decoders. Decoders don't differentiate between normal,
1374  * unofficial and experimental (that is, they always try to decode things
1375  * when they can) unless they are explicitly asked to behave stupidly
1376  * (=strictly conform to the specs)
1377  * This may only be set to one of the FF_COMPLIANCE_* values in defs.h.
1378  */
1380 
1381  /**
1382  * error concealment flags
1383  * - encoding: unused
1384  * - decoding: Set by user.
1385  */
1387 #define FF_EC_GUESS_MVS 1
1388 #define FF_EC_DEBLOCK 2
1389 #define FF_EC_FAVOR_INTER 256
1390 
1391  /**
1392  * debug
1393  * - encoding: Set by user.
1394  * - decoding: Set by user.
1395  */
1396  int debug;
1397 #define FF_DEBUG_PICT_INFO 1
1398 #define FF_DEBUG_RC 2
1399 #define FF_DEBUG_BITSTREAM 4
1400 #define FF_DEBUG_MB_TYPE 8
1401 #define FF_DEBUG_QP 16
1402 #define FF_DEBUG_DCT_COEFF 0x00000040
1403 #define FF_DEBUG_SKIP 0x00000080
1404 #define FF_DEBUG_STARTCODE 0x00000100
1405 #define FF_DEBUG_ER 0x00000400
1406 #define FF_DEBUG_MMCO 0x00000800
1407 #define FF_DEBUG_BUGS 0x00001000
1408 #define FF_DEBUG_BUFFERS 0x00008000
1409 #define FF_DEBUG_THREADS 0x00010000
1410 #define FF_DEBUG_GREEN_MD 0x00800000
1411 #define FF_DEBUG_NOMC 0x01000000
1412 
1413  /**
1414  * Error recognition; may misdetect some more or less valid parts as errors.
1415  * This is a bitfield of the AV_EF_* values defined in defs.h.
1416  *
1417  * - encoding: Set by user.
1418  * - decoding: Set by user.
1419  */
1421 
1422  /**
1423  * Hardware accelerator in use
1424  * - encoding: unused.
1425  * - decoding: Set by libavcodec
1426  */
1427  const struct AVHWAccel *hwaccel;
1428 
1429  /**
1430  * Legacy hardware accelerator context.
1431  *
1432  * For some hardware acceleration methods, the caller may use this field to
1433  * signal hwaccel-specific data to the codec. The struct pointed to by this
1434  * pointer is hwaccel-dependent and defined in the respective header. Please
1435  * refer to the FFmpeg HW accelerator documentation to know how to fill
1436  * this.
1437  *
1438  * In most cases this field is optional - the necessary information may also
1439  * be provided to libavcodec through @ref hw_frames_ctx or @ref
1440  * hw_device_ctx (see avcodec_get_hw_config()). However, in some cases it
1441  * may be the only method of signalling some (optional) information.
1442  *
1443  * The struct and its contents are owned by the caller.
1444  *
1445  * - encoding: May be set by the caller before avcodec_open2(). Must remain
1446  * valid until avcodec_free_context().
1447  * - decoding: May be set by the caller in the get_format() callback.
1448  * Must remain valid until the next get_format() call,
1449  * or avcodec_free_context() (whichever comes first).
1450  */
1452 
1453  /**
1454  * A reference to the AVHWFramesContext describing the input (for encoding)
1455  * or output (decoding) frames. The reference is set by the caller and
1456  * afterwards owned (and freed) by libavcodec - it should never be read by
1457  * the caller after being set.
1458  *
1459  * - decoding: This field should be set by the caller from the get_format()
1460  * callback. The previous reference (if any) will always be
1461  * unreffed by libavcodec before the get_format() call.
1462  *
1463  * If the default get_buffer2() is used with a hwaccel pixel
1464  * format, then this AVHWFramesContext will be used for
1465  * allocating the frame buffers.
1466  *
1467  * - encoding: For hardware encoders configured to use a hwaccel pixel
1468  * format, this field should be set by the caller to a reference
1469  * to the AVHWFramesContext describing input frames.
1470  * AVHWFramesContext.format must be equal to
1471  * AVCodecContext.pix_fmt.
1472  *
1473  * This field should be set before avcodec_open2() is called.
1474  */
1476 
1477  /**
1478  * A reference to the AVHWDeviceContext describing the device which will
1479  * be used by a hardware encoder/decoder. The reference is set by the
1480  * caller and afterwards owned (and freed) by libavcodec.
1481  *
1482  * This should be used if either the codec device does not require
1483  * hardware frames or any that are used are to be allocated internally by
1484  * libavcodec. If the user wishes to supply any of the frames used as
1485  * encoder input or decoder output then hw_frames_ctx should be used
1486  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
1487  * field will be ignored while decoding the associated stream segment, but
1488  * may again be used on a following one after another get_format() call.
1489  *
1490  * For both encoders and decoders this field should be set before
1491  * avcodec_open2() is called and must not be written to thereafter.
1492  *
1493  * Note that some decoders may require this field to be set initially in
1494  * order to support hw_frames_ctx at all - in that case, all frames
1495  * contexts used must be created on the same device.
1496  */
1498 
1499  /**
1500  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
1501  * decoding (if active).
1502  * - encoding: unused
1503  * - decoding: Set by user (either before avcodec_open2(), or in the
1504  * AVCodecContext.get_format callback)
1505  */
1507 
1508  /**
1509  * Video decoding only. Sets the number of extra hardware frames which
1510  * the decoder will allocate for use by the caller. This must be set
1511  * before avcodec_open2() is called.
1512  *
1513  * Some hardware decoders require all frames that they will use for
1514  * output to be defined in advance before decoding starts. For such
1515  * decoders, the hardware frame pool must therefore be of a fixed size.
1516  * The extra frames set here are on top of any number that the decoder
1517  * needs internally in order to operate normally (for example, frames
1518  * used as reference pictures).
1519  */
1521 
1522  /**
1523  * error
1524  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
1525  * - decoding: unused
1526  */
1528 
1529  /**
1530  * DCT algorithm, see FF_DCT_* below
1531  * - encoding: Set by user.
1532  * - decoding: unused
1533  */
1535 #define FF_DCT_AUTO 0
1536 #define FF_DCT_FASTINT 1
1537 #define FF_DCT_INT 2
1538 #define FF_DCT_MMX 3
1539 #define FF_DCT_ALTIVEC 5
1540 #define FF_DCT_FAAN 6
1541 
1542  /**
1543  * IDCT algorithm, see FF_IDCT_* below.
1544  * - encoding: Set by user.
1545  * - decoding: Set by user.
1546  */
1548 #define FF_IDCT_AUTO 0
1549 #define FF_IDCT_INT 1
1550 #define FF_IDCT_SIMPLE 2
1551 #define FF_IDCT_SIMPLEMMX 3
1552 #define FF_IDCT_ARM 7
1553 #define FF_IDCT_ALTIVEC 8
1554 #define FF_IDCT_SIMPLEARM 10
1555 #define FF_IDCT_XVID 14
1556 #define FF_IDCT_SIMPLEARMV5TE 16
1557 #define FF_IDCT_SIMPLEARMV6 17
1558 #define FF_IDCT_FAAN 20
1559 #define FF_IDCT_SIMPLENEON 22
1560 #define FF_IDCT_SIMPLEAUTO 128
1561 
1562  /**
1563  * bits per sample/pixel from the demuxer (needed for huffyuv).
1564  * - encoding: Set by libavcodec.
1565  * - decoding: Set by user.
1566  */
1568 
1569  /**
1570  * Bits per sample/pixel of internal libavcodec pixel/sample format.
1571  * - encoding: set by user.
1572  * - decoding: set by libavcodec.
1573  */
1575 
1576  /**
1577  * thread count
1578  * is used to decide how many independent tasks should be passed to execute()
1579  * - encoding: Set by user.
1580  * - decoding: Set by user.
1581  */
1583 
1584  /**
1585  * Which multithreading methods to use.
1586  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
1587  * so clients which cannot provide future frames should not use it.
1588  *
1589  * - encoding: Set by user, otherwise the default is used.
1590  * - decoding: Set by user, otherwise the default is used.
1591  */
1593 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
1594 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
1595 
1596  /**
1597  * Which multithreading methods are in use by the codec.
1598  * - encoding: Set by libavcodec.
1599  * - decoding: Set by libavcodec.
1600  */
1602 
1603  /**
1604  * The codec may call this to execute several independent things.
1605  * It will return only after finishing all tasks.
1606  * The user may replace this with some multithreaded implementation,
1607  * the default implementation will execute the parts serially.
1608  * @param count the number of things to execute
1609  * - encoding: Set by libavcodec, user can override.
1610  * - decoding: Set by libavcodec, user can override.
1611  */
1612  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
1613 
1614  /**
1615  * The codec may call this to execute several independent things.
1616  * It will return only after finishing all tasks.
1617  * The user may replace this with some multithreaded implementation,
1618  * the default implementation will execute the parts serially.
1619  * @param c context passed also to func
1620  * @param count the number of things to execute
1621  * @param arg2 argument passed unchanged to func
1622  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
1623  * @param func function that will be called count times, with jobnr from 0 to count-1.
1624  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
1625  * two instances of func executing at the same time will have the same threadnr.
1626  * @return always 0 currently, but code should handle a future improvement where when any call to func
1627  * returns < 0 no further calls to func may be done and < 0 is returned.
1628  * - encoding: Set by libavcodec, user can override.
1629  * - decoding: Set by libavcodec, user can override.
1630  */
1631  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
1632 
1633  /**
1634  * profile
1635  * - encoding: Set by user.
1636  * - decoding: Set by libavcodec.
1637  * See the AV_PROFILE_* defines in defs.h.
1638  */
1639  int profile;
1640 #if FF_API_FF_PROFILE_LEVEL
1641  /** @deprecated The following defines are deprecated; use AV_PROFILE_*
1642  * in defs.h instead. */
1643 #define FF_PROFILE_UNKNOWN -99
1644 #define FF_PROFILE_RESERVED -100
1645 
1646 #define FF_PROFILE_AAC_MAIN 0
1647 #define FF_PROFILE_AAC_LOW 1
1648 #define FF_PROFILE_AAC_SSR 2
1649 #define FF_PROFILE_AAC_LTP 3
1650 #define FF_PROFILE_AAC_HE 4
1651 #define FF_PROFILE_AAC_HE_V2 28
1652 #define FF_PROFILE_AAC_LD 22
1653 #define FF_PROFILE_AAC_ELD 38
1654 #define FF_PROFILE_MPEG2_AAC_LOW 128
1655 #define FF_PROFILE_MPEG2_AAC_HE 131
1656 
1657 #define FF_PROFILE_DNXHD 0
1658 #define FF_PROFILE_DNXHR_LB 1
1659 #define FF_PROFILE_DNXHR_SQ 2
1660 #define FF_PROFILE_DNXHR_HQ 3
1661 #define FF_PROFILE_DNXHR_HQX 4
1662 #define FF_PROFILE_DNXHR_444 5
1663 
1664 #define FF_PROFILE_DTS 20
1665 #define FF_PROFILE_DTS_ES 30
1666 #define FF_PROFILE_DTS_96_24 40
1667 #define FF_PROFILE_DTS_HD_HRA 50
1668 #define FF_PROFILE_DTS_HD_MA 60
1669 #define FF_PROFILE_DTS_EXPRESS 70
1670 #define FF_PROFILE_DTS_HD_MA_X 61
1671 #define FF_PROFILE_DTS_HD_MA_X_IMAX 62
1672 
1673 
1674 #define FF_PROFILE_EAC3_DDP_ATMOS 30
1675 
1676 #define FF_PROFILE_TRUEHD_ATMOS 30
1677 
1678 #define FF_PROFILE_MPEG2_422 0
1679 #define FF_PROFILE_MPEG2_HIGH 1
1680 #define FF_PROFILE_MPEG2_SS 2
1681 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
1682 #define FF_PROFILE_MPEG2_MAIN 4
1683 #define FF_PROFILE_MPEG2_SIMPLE 5
1684 
1685 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
1686 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
1687 
1688 #define FF_PROFILE_H264_BASELINE 66
1689 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
1690 #define FF_PROFILE_H264_MAIN 77
1691 #define FF_PROFILE_H264_EXTENDED 88
1692 #define FF_PROFILE_H264_HIGH 100
1693 #define FF_PROFILE_H264_HIGH_10 110
1694 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
1695 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
1696 #define FF_PROFILE_H264_HIGH_422 122
1697 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
1698 #define FF_PROFILE_H264_STEREO_HIGH 128
1699 #define FF_PROFILE_H264_HIGH_444 144
1700 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
1701 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
1702 #define FF_PROFILE_H264_CAVLC_444 44
1703 
1704 #define FF_PROFILE_VC1_SIMPLE 0
1705 #define FF_PROFILE_VC1_MAIN 1
1706 #define FF_PROFILE_VC1_COMPLEX 2
1707 #define FF_PROFILE_VC1_ADVANCED 3
1708 
1709 #define FF_PROFILE_MPEG4_SIMPLE 0
1710 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
1711 #define FF_PROFILE_MPEG4_CORE 2
1712 #define FF_PROFILE_MPEG4_MAIN 3
1713 #define FF_PROFILE_MPEG4_N_BIT 4
1714 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
1715 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
1716 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
1717 #define FF_PROFILE_MPEG4_HYBRID 8
1718 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
1719 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
1720 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
1721 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
1722 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
1723 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
1724 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
1725 
1726 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
1727 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
1728 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
1729 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
1730 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
1731 
1732 #define FF_PROFILE_VP9_0 0
1733 #define FF_PROFILE_VP9_1 1
1734 #define FF_PROFILE_VP9_2 2
1735 #define FF_PROFILE_VP9_3 3
1736 
1737 #define FF_PROFILE_HEVC_MAIN 1
1738 #define FF_PROFILE_HEVC_MAIN_10 2
1739 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
1740 #define FF_PROFILE_HEVC_REXT 4
1741 #define FF_PROFILE_HEVC_SCC 9
1742 
1743 #define FF_PROFILE_VVC_MAIN_10 1
1744 #define FF_PROFILE_VVC_MAIN_10_444 33
1745 
1746 #define FF_PROFILE_AV1_MAIN 0
1747 #define FF_PROFILE_AV1_HIGH 1
1748 #define FF_PROFILE_AV1_PROFESSIONAL 2
1749 
1750 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
1751 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
1752 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
1753 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
1754 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
1755 
1756 #define FF_PROFILE_SBC_MSBC 1
1757 
1758 #define FF_PROFILE_PRORES_PROXY 0
1759 #define FF_PROFILE_PRORES_LT 1
1760 #define FF_PROFILE_PRORES_STANDARD 2
1761 #define FF_PROFILE_PRORES_HQ 3
1762 #define FF_PROFILE_PRORES_4444 4
1763 #define FF_PROFILE_PRORES_XQ 5
1764 
1765 #define FF_PROFILE_ARIB_PROFILE_A 0
1766 #define FF_PROFILE_ARIB_PROFILE_C 1
1767 
1768 #define FF_PROFILE_KLVA_SYNC 0
1769 #define FF_PROFILE_KLVA_ASYNC 1
1770 
1771 #define FF_PROFILE_EVC_BASELINE 0
1772 #define FF_PROFILE_EVC_MAIN 1
1773 #endif
1774 
1775  /**
1776  * Encoding level descriptor.
1777  * - encoding: Set by user, corresponds to a specific level defined by the
1778  * codec, usually corresponding to the profile level, if not specified it
1779  * is set to FF_LEVEL_UNKNOWN.
1780  * - decoding: Set by libavcodec.
1781  * See AV_LEVEL_* in defs.h.
1782  */
1783  int level;
1784 #if FF_API_FF_PROFILE_LEVEL
1785  /** @deprecated The following define is deprecated; use AV_LEVEL_UNKOWN
1786  * in defs.h instead. */
1787 #define FF_LEVEL_UNKNOWN -99
1788 #endif
1789 
1790  /**
1791  * Properties of the stream that gets decoded
1792  * - encoding: unused
1793  * - decoding: set by libavcodec
1794  */
1795  unsigned properties;
1796 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
1797 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
1798 #define FF_CODEC_PROPERTY_FILM_GRAIN 0x00000004
1799 
1800  /**
1801  * Skip loop filtering for selected frames.
1802  * - encoding: unused
1803  * - decoding: Set by user.
1804  */
1806 
1807  /**
1808  * Skip IDCT/dequantization for selected frames.
1809  * - encoding: unused
1810  * - decoding: Set by user.
1811  */
1813 
1814  /**
1815  * Skip decoding for selected frames.
1816  * - encoding: unused
1817  * - decoding: Set by user.
1818  */
1820 
1821  /**
1822  * Skip processing alpha if supported by codec.
1823  * Note that if the format uses pre-multiplied alpha (common with VP6,
1824  * and recommended due to better video quality/compression)
1825  * the image will look as if alpha-blended onto a black background.
1826  * However for formats that do not use pre-multiplied alpha
1827  * there might be serious artefacts (though e.g. libswscale currently
1828  * assumes pre-multiplied alpha anyway).
1829  *
1830  * - decoding: set by user
1831  * - encoding: unused
1832  */
1834 
1835  /**
1836  * Number of macroblock rows at the top which are skipped.
1837  * - encoding: unused
1838  * - decoding: Set by user.
1839  */
1841 
1842  /**
1843  * Number of macroblock rows at the bottom which are skipped.
1844  * - encoding: unused
1845  * - decoding: Set by user.
1846  */
1848 
1849  /**
1850  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
1851  * - encoding: unused
1852  * - decoding: Set by user.
1853  */
1854  int lowres;
1855 
1856  /**
1857  * AVCodecDescriptor
1858  * - encoding: unused.
1859  * - decoding: set by libavcodec.
1860  */
1862 
1863  /**
1864  * Character encoding of the input subtitles file.
1865  * - decoding: set by user
1866  * - encoding: unused
1867  */
1869 
1870  /**
1871  * Subtitles character encoding mode. Formats or codecs might be adjusting
1872  * this setting (if they are doing the conversion themselves for instance).
1873  * - decoding: set by libavcodec
1874  * - encoding: unused
1875  */
1877 #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)
1878 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
1879 #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
1880 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
1881 
1882  /**
1883  * Header containing style information for text subtitles.
1884  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
1885  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
1886  * the Format line following. It shouldn't include any Dialogue line.
1887  * - encoding: Set/allocated/freed by user (before avcodec_open2())
1888  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
1889  */
1892 
1893  /**
1894  * dump format separator.
1895  * can be ", " or "\n " or anything else
1896  * - encoding: Set by user.
1897  * - decoding: Set by user.
1898  */
1899  uint8_t *dump_separator;
1900 
1901  /**
1902  * ',' separated list of allowed decoders.
1903  * If NULL then all are allowed
1904  * - encoding: unused
1905  * - decoding: set by user
1906  */
1908 
1909  /**
1910  * Additional data associated with the entire coded stream.
1911  *
1912  * - decoding: may be set by user before calling avcodec_open2().
1913  * - encoding: may be set by libavcodec after avcodec_open2().
1914  */
1917 
1918  /**
1919  * Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of
1920  * metadata exported in frame, packet, or coded stream side data by
1921  * decoders and encoders.
1922  *
1923  * - decoding: set by user
1924  * - encoding: set by user
1925  */
1927 
1928  /**
1929  * The number of pixels per image to maximally accept.
1930  *
1931  * - decoding: set by user
1932  * - encoding: set by user
1933  */
1934  int64_t max_pixels;
1935 
1936  /**
1937  * Video decoding only. Certain video codecs support cropping, meaning that
1938  * only a sub-rectangle of the decoded frame is intended for display. This
1939  * option controls how cropping is handled by libavcodec.
1940  *
1941  * When set to 1 (the default), libavcodec will apply cropping internally.
1942  * I.e. it will modify the output frame width/height fields and offset the
1943  * data pointers (only by as much as possible while preserving alignment, or
1944  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
1945  * the frames output by the decoder refer only to the cropped area. The
1946  * crop_* fields of the output frames will be zero.
1947  *
1948  * When set to 0, the width/height fields of the output frames will be set
1949  * to the coded dimensions and the crop_* fields will describe the cropping
1950  * rectangle. Applying the cropping is left to the caller.
1951  *
1952  * @warning When hardware acceleration with opaque output frames is used,
1953  * libavcodec is unable to apply cropping from the top/left border.
1954  *
1955  * @note when this option is set to zero, the width/height fields of the
1956  * AVCodecContext and output AVFrames have different meanings. The codec
1957  * context fields store display dimensions (with the coded dimensions in
1958  * coded_width/height), while the frame fields store the coded dimensions
1959  * (with the display dimensions being determined by the crop_* fields).
1960  */
1962 
1963  /**
1964  * The percentage of damaged samples to discard a frame.
1965  *
1966  * - decoding: set by user
1967  * - encoding: unused
1968  */
1970 
1971  /**
1972  * The number of samples per frame to maximally accept.
1973  *
1974  * - decoding: set by user
1975  * - encoding: set by user
1976  */
1977  int64_t max_samples;
1978 
1979  /**
1980  * This callback is called at the beginning of each packet to get a data
1981  * buffer for it.
1982  *
1983  * The following field will be set in the packet before this callback is
1984  * called:
1985  * - size
1986  * This callback must use the above value to calculate the required buffer size,
1987  * which must padded by at least AV_INPUT_BUFFER_PADDING_SIZE bytes.
1988  *
1989  * In some specific cases, the encoder may not use the entire buffer allocated by this
1990  * callback. This will be reflected in the size value in the packet once returned by
1991  * avcodec_receive_packet().
1992  *
1993  * This callback must fill the following fields in the packet:
1994  * - data: alignment requirements for AVPacket apply, if any. Some architectures and
1995  * encoders may benefit from having aligned data.
1996  * - buf: must contain a pointer to an AVBufferRef structure. The packet's
1997  * data pointer must be contained in it. See: av_buffer_create(), av_buffer_alloc(),
1998  * and av_buffer_ref().
1999  *
2000  * If AV_CODEC_CAP_DR1 is not set then get_encode_buffer() must call
2001  * avcodec_default_get_encode_buffer() instead of providing a buffer allocated by
2002  * some other means.
2003  *
2004  * The flags field may contain a combination of AV_GET_ENCODE_BUFFER_FLAG_ flags.
2005  * They may be used for example to hint what use the buffer may get after being
2006  * created.
2007  * Implementations of this callback may ignore flags they don't understand.
2008  * If AV_GET_ENCODE_BUFFER_FLAG_REF is set in flags then the packet may be reused
2009  * (read and/or written to if it is writable) later by libavcodec.
2010  *
2011  * This callback must be thread-safe, as when frame threading is used, it may
2012  * be called from multiple threads simultaneously.
2013  *
2014  * @see avcodec_default_get_encode_buffer()
2015  *
2016  * - encoding: Set by libavcodec, user can override.
2017  * - decoding: unused
2018  */
2020 
2021  /**
2022  * Frame counter, set by libavcodec.
2023  *
2024  * - decoding: total number of frames returned from the decoder so far.
2025  * - encoding: total number of frames passed to the encoder so far.
2026  *
2027  * @note the counter is not incremented if encoding/decoding resulted in
2028  * an error.
2029  */
2030  int64_t frame_num;
2031 
2032  /**
2033  * Decoding only. May be set by the caller before avcodec_open2() to an
2034  * av_malloc()'ed array (or via AVOptions). Owned and freed by the decoder
2035  * afterwards.
2036  *
2037  * Side data attached to decoded frames may come from several sources:
2038  * 1. coded_side_data, which the decoder will for certain types translate
2039  * from packet-type to frame-type and attach to frames;
2040  * 2. side data attached to an AVPacket sent for decoding (same
2041  * considerations as above);
2042  * 3. extracted from the coded bytestream.
2043  * The first two cases are supplied by the caller and typically come from a
2044  * container.
2045  *
2046  * This array configures decoder behaviour in cases when side data of the
2047  * same type is present both in the coded bytestream and in the
2048  * user-supplied side data (items 1. and 2. above). In all cases, at most
2049  * one instance of each side data type will be attached to output frames. By
2050  * default it will be the bytestream side data. Adding an
2051  * AVPacketSideDataType value to this array will flip the preference for
2052  * this type, thus making the decoder prefer user-supplied side data over
2053  * bytestream. In case side data of the same type is present both in
2054  * coded_data and attacked to a packet, the packet instance always has
2055  * priority.
2056  *
2057  * The array may also contain a single -1, in which case the preference is
2058  * switched for all side data types.
2059  */
2061  /**
2062  * Number of entries in side_data_prefer_packet.
2063  */
2065 } AVCodecContext;
2066 
2067 /**
2068  * @defgroup lavc_hwaccel AVHWAccel
2069  *
2070  * @note Nothing in this structure should be accessed by the user. At some
2071  * point in future it will not be externally visible at all.
2072  *
2073  * @{
2074  */
2075 typedef struct AVHWAccel {
2076  /**
2077  * Name of the hardware accelerated codec.
2078  * The name is globally unique among encoders and among decoders (but an
2079  * encoder and a decoder can share the same name).
2080  */
2081  const char *name;
2082 
2083  /**
2084  * Type of codec implemented by the hardware accelerator.
2085  *
2086  * See AVMEDIA_TYPE_xxx
2087  */
2089 
2090  /**
2091  * Codec implemented by the hardware accelerator.
2092  *
2093  * See AV_CODEC_ID_xxx
2094  */
2096 
2097  /**
2098  * Supported pixel format.
2099  *
2100  * Only hardware accelerated formats are supported here.
2101  */
2103 
2104  /**
2105  * Hardware accelerated codec capabilities.
2106  * see AV_HWACCEL_CODEC_CAP_*
2107  */
2109 } AVHWAccel;
2110 
2111 /**
2112  * HWAccel is experimental and is thus avoided in favor of non experimental
2113  * codecs
2114  */
2115 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
2116 
2117 /**
2118  * Hardware acceleration should be used for decoding even if the codec level
2119  * used is unknown or higher than the maximum supported level reported by the
2120  * hardware driver.
2121  *
2122  * It's generally a good idea to pass this flag unless you have a specific
2123  * reason not to, as hardware tends to under-report supported levels.
2124  */
2125 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
2126 
2127 /**
2128  * Hardware acceleration can output YUV pixel formats with a different chroma
2129  * sampling than 4:2:0 and/or other than 8 bits per component.
2130  */
2131 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
2132 
2133 /**
2134  * Hardware acceleration should still be attempted for decoding when the
2135  * codec profile does not match the reported capabilities of the hardware.
2136  *
2137  * For example, this can be used to try to decode baseline profile H.264
2138  * streams in hardware - it will often succeed, because many streams marked
2139  * as baseline profile actually conform to constrained baseline profile.
2140  *
2141  * @warning If the stream is actually not supported then the behaviour is
2142  * undefined, and may include returning entirely incorrect output
2143  * while indicating success.
2144  */
2145 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
2146 
2147 /**
2148  * Some hardware decoders (namely nvdec) can either output direct decoder
2149  * surfaces, or make an on-device copy and return said copy.
2150  * There is a hard limit on how many decoder surfaces there can be, and it
2151  * cannot be accurately guessed ahead of time.
2152  * For some processing chains, this can be okay, but others will run into the
2153  * limit and in turn produce very confusing errors that require fine tuning of
2154  * more or less obscure options by the user, or in extreme cases cannot be
2155  * resolved at all without inserting an avfilter that forces a copy.
2156  *
2157  * Thus, the hwaccel will by default make a copy for safety and resilience.
2158  * If a users really wants to minimize the amount of copies, they can set this
2159  * flag and ensure their processing chain does not exhaust the surface pool.
2160  */
2161 #define AV_HWACCEL_FLAG_UNSAFE_OUTPUT (1 << 3)
2162 
2163 /**
2164  * @}
2165  */
2166 
2169 
2170  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
2171 
2172  /**
2173  * Plain text, the text field must be set by the decoder and is
2174  * authoritative. ass and pict fields may contain approximations.
2175  */
2177 
2178  /**
2179  * Formatted text, the ass field must be set by the decoder and is
2180  * authoritative. pict and text fields may contain approximations.
2181  */
2183 };
2184 
2185 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
2186 
2187 typedef struct AVSubtitleRect {
2188  int x; ///< top left corner of pict, undefined when pict is not set
2189  int y; ///< top left corner of pict, undefined when pict is not set
2190  int w; ///< width of pict, undefined when pict is not set
2191  int h; ///< height of pict, undefined when pict is not set
2192  int nb_colors; ///< number of colors in pict, undefined when pict is not set
2193 
2194  /**
2195  * data+linesize for the bitmap of this subtitle.
2196  * Can be set for text/ass as well once they are rendered.
2197  */
2198  uint8_t *data[4];
2199  int linesize[4];
2200 
2201  int flags;
2203 
2204  char *text; ///< 0 terminated plain UTF-8 text
2205 
2206  /**
2207  * 0 terminated ASS/SSA compatible event line.
2208  * The presentation of this is unaffected by the other values in this
2209  * struct.
2210  */
2211  char *ass;
2212 } AVSubtitleRect;
2213 
2214 typedef struct AVSubtitle {
2215  uint16_t format; /* 0 = graphics */
2216  uint32_t start_display_time; /* relative to packet pts, in ms */
2217  uint32_t end_display_time; /* relative to packet pts, in ms */
2218  unsigned num_rects;
2220  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
2221 } AVSubtitle;
2222 
2223 /**
2224  * Return the LIBAVCODEC_VERSION_INT constant.
2225  */
2226 unsigned avcodec_version(void);
2227 
2228 /**
2229  * Return the libavcodec build-time configuration.
2230  */
2231 const char *avcodec_configuration(void);
2232 
2233 /**
2234  * Return the libavcodec license.
2235  */
2236 const char *avcodec_license(void);
2237 
2238 /**
2239  * Allocate an AVCodecContext and set its fields to default values. The
2240  * resulting struct should be freed with avcodec_free_context().
2241  *
2242  * @param codec if non-NULL, allocate private data and initialize defaults
2243  * for the given codec. It is illegal to then call avcodec_open2()
2244  * with a different codec.
2245  * If NULL, then the codec-specific defaults won't be initialized,
2246  * which may result in suboptimal default settings (this is
2247  * important mainly for encoders, e.g. libx264).
2248  *
2249  * @return An AVCodecContext filled with default values or NULL on failure.
2250  */
2252 
2253 /**
2254  * Free the codec context and everything associated with it and write NULL to
2255  * the provided pointer.
2256  */
2257 void avcodec_free_context(AVCodecContext **avctx);
2258 
2259 /**
2260  * Get the AVClass for AVCodecContext. It can be used in combination with
2261  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2262  *
2263  * @see av_opt_find().
2264  */
2265 const AVClass *avcodec_get_class(void);
2266 
2267 /**
2268  * Get the AVClass for AVSubtitleRect. It can be used in combination with
2269  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
2270  *
2271  * @see av_opt_find().
2272  */
2274 
2275 /**
2276  * Fill the parameters struct based on the values from the supplied codec
2277  * context. Any allocated fields in par are freed and replaced with duplicates
2278  * of the corresponding fields in codec.
2279  *
2280  * @return >= 0 on success, a negative AVERROR code on failure
2281  */
2283  const AVCodecContext *codec);
2284 
2285 /**
2286  * Fill the codec context based on the values from the supplied codec
2287  * parameters. Any allocated fields in codec that have a corresponding field in
2288  * par are freed and replaced with duplicates of the corresponding field in par.
2289  * Fields in codec that do not have a counterpart in par are not touched.
2290  *
2291  * @return >= 0 on success, a negative AVERROR code on failure.
2292  */
2294  const struct AVCodecParameters *par);
2295 
2296 /**
2297  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
2298  * function the context has to be allocated with avcodec_alloc_context3().
2299  *
2300  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
2301  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
2302  * retrieving a codec.
2303  *
2304  * Depending on the codec, you might need to set options in the codec context
2305  * also for decoding (e.g. width, height, or the pixel or audio sample format in
2306  * the case the information is not available in the bitstream, as when decoding
2307  * raw audio or video).
2308  *
2309  * Options in the codec context can be set either by setting them in the options
2310  * AVDictionary, or by setting the values in the context itself, directly or by
2311  * using the av_opt_set() API before calling this function.
2312  *
2313  * Example:
2314  * @code
2315  * av_dict_set(&opts, "b", "2.5M", 0);
2316  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
2317  * if (!codec)
2318  * exit(1);
2319  *
2320  * context = avcodec_alloc_context3(codec);
2321  *
2322  * if (avcodec_open2(context, codec, opts) < 0)
2323  * exit(1);
2324  * @endcode
2325  *
2326  * In the case AVCodecParameters are available (e.g. when demuxing a stream
2327  * using libavformat, and accessing the AVStream contained in the demuxer), the
2328  * codec parameters can be copied to the codec context using
2329  * avcodec_parameters_to_context(), as in the following example:
2330  *
2331  * @code
2332  * AVStream *stream = ...;
2333  * context = avcodec_alloc_context3(codec);
2334  * if (avcodec_parameters_to_context(context, stream->codecpar) < 0)
2335  * exit(1);
2336  * if (avcodec_open2(context, codec, NULL) < 0)
2337  * exit(1);
2338  * @endcode
2339  *
2340  * @note Always call this function before using decoding routines (such as
2341  * @ref avcodec_receive_frame()).
2342  *
2343  * @param avctx The context to initialize.
2344  * @param codec The codec to open this context for. If a non-NULL codec has been
2345  * previously passed to avcodec_alloc_context3() or
2346  * for this context, then this parameter MUST be either NULL or
2347  * equal to the previously passed codec.
2348  * @param options A dictionary filled with AVCodecContext and codec-private
2349  * options, which are set on top of the options already set in
2350  * avctx, can be NULL. On return this object will be filled with
2351  * options that were not found in the avctx codec context.
2352  *
2353  * @return zero on success, a negative value on error
2354  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
2355  * av_dict_set(), av_opt_set(), av_opt_find(), avcodec_parameters_to_context()
2356  */
2357 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
2358 
2359 #if FF_API_AVCODEC_CLOSE
2360 /**
2361  * Close a given AVCodecContext and free all the data associated with it
2362  * (but not the AVCodecContext itself).
2363  *
2364  * Calling this function on an AVCodecContext that hasn't been opened will free
2365  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
2366  * codec. Subsequent calls will do nothing.
2367  *
2368  * @deprecated Do not use this function. Use avcodec_free_context() to destroy a
2369  * codec context (either open or closed). Opening and closing a codec context
2370  * multiple times is not supported anymore -- use multiple codec contexts
2371  * instead.
2372  */
2374 int avcodec_close(AVCodecContext *avctx);
2375 #endif
2376 
2377 /**
2378  * Free all allocated data in the given subtitle struct.
2379  *
2380  * @param sub AVSubtitle to free.
2381  */
2382 void avsubtitle_free(AVSubtitle *sub);
2383 
2384 /**
2385  * @}
2386  */
2387 
2388 /**
2389  * @addtogroup lavc_decoding
2390  * @{
2391  */
2392 
2393 /**
2394  * The default callback for AVCodecContext.get_buffer2(). It is made public so
2395  * it can be called by custom get_buffer2() implementations for decoders without
2396  * AV_CODEC_CAP_DR1 set.
2397  */
2399 
2400 /**
2401  * The default callback for AVCodecContext.get_encode_buffer(). It is made public so
2402  * it can be called by custom get_encode_buffer() implementations for encoders without
2403  * AV_CODEC_CAP_DR1 set.
2404  */
2406 
2407 /**
2408  * Modify width and height values so that they will result in a memory
2409  * buffer that is acceptable for the codec if you do not use any horizontal
2410  * padding.
2411  *
2412  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2413  */
2415 
2416 /**
2417  * Modify width and height values so that they will result in a memory
2418  * buffer that is acceptable for the codec if you also ensure that all
2419  * line sizes are a multiple of the respective linesize_align[i].
2420  *
2421  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
2422  */
2424  int linesize_align[AV_NUM_DATA_POINTERS]);
2425 
2426 /**
2427  * Decode a subtitle message.
2428  * Return a negative value on error, otherwise return the number of bytes used.
2429  * If no subtitle could be decompressed, got_sub_ptr is zero.
2430  * Otherwise, the subtitle is stored in *sub.
2431  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
2432  * simplicity, because the performance difference is expected to be negligible
2433  * and reusing a get_buffer written for video codecs would probably perform badly
2434  * due to a potentially very different allocation pattern.
2435  *
2436  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
2437  * and output. This means that for some packets they will not immediately
2438  * produce decoded output and need to be flushed at the end of decoding to get
2439  * all the decoded data. Flushing is done by calling this function with packets
2440  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
2441  * returning subtitles. It is safe to flush even those decoders that are not
2442  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
2443  *
2444  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2445  * before packets may be fed to the decoder.
2446  *
2447  * @param avctx the codec context
2448  * @param[out] sub The preallocated AVSubtitle in which the decoded subtitle will be stored,
2449  * must be freed with avsubtitle_free if *got_sub_ptr is set.
2450  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
2451  * @param[in] avpkt The input AVPacket containing the input buffer.
2452  */
2454  int *got_sub_ptr, const AVPacket *avpkt);
2455 
2456 /**
2457  * Supply raw packet data as input to a decoder.
2458  *
2459  * Internally, this call will copy relevant AVCodecContext fields, which can
2460  * influence decoding per-packet, and apply them when the packet is actually
2461  * decoded. (For example AVCodecContext.skip_frame, which might direct the
2462  * decoder to drop the frame contained by the packet sent with this function.)
2463  *
2464  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
2465  * larger than the actual read bytes because some optimized bitstream
2466  * readers read 32 or 64 bits at once and could read over the end.
2467  *
2468  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
2469  * before packets may be fed to the decoder.
2470  *
2471  * @param avctx codec context
2472  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
2473  * frame, or several complete audio frames.
2474  * Ownership of the packet remains with the caller, and the
2475  * decoder will not write to the packet. The decoder may create
2476  * a reference to the packet data (or copy it if the packet is
2477  * not reference-counted).
2478  * Unlike with older APIs, the packet is always fully consumed,
2479  * and if it contains multiple frames (e.g. some audio codecs),
2480  * will require you to call avcodec_receive_frame() multiple
2481  * times afterwards before you can send a new packet.
2482  * It can be NULL (or an AVPacket with data set to NULL and
2483  * size set to 0); in this case, it is considered a flush
2484  * packet, which signals the end of the stream. Sending the
2485  * first flush packet will return success. Subsequent ones are
2486  * unnecessary and will return AVERROR_EOF. If the decoder
2487  * still has frames buffered, it will return them after sending
2488  * a flush packet.
2489  *
2490  * @retval 0 success
2491  * @retval AVERROR(EAGAIN) input is not accepted in the current state - user
2492  * must read output with avcodec_receive_frame() (once
2493  * all output is read, the packet should be resent,
2494  * and the call will not fail with EAGAIN).
2495  * @retval AVERROR_EOF the decoder has been flushed, and no new packets can be
2496  * sent to it (also returned if more than 1 flush
2497  * packet is sent)
2498  * @retval AVERROR(EINVAL) codec not opened, it is an encoder, or requires flush
2499  * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2500  * @retval "another negative error code" legitimate decoding errors
2501  */
2502 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
2503 
2504 /**
2505  * Return decoded output data from a decoder or encoder (when the
2506  * @ref AV_CODEC_FLAG_RECON_FRAME flag is used).
2507  *
2508  * @param avctx codec context
2509  * @param frame This will be set to a reference-counted video or audio
2510  * frame (depending on the decoder type) allocated by the
2511  * codec. Note that the function will always call
2512  * av_frame_unref(frame) before doing anything else.
2513  *
2514  * @retval 0 success, a frame was returned
2515  * @retval AVERROR(EAGAIN) output is not available in this state - user must
2516  * try to send new input
2517  * @retval AVERROR_EOF the codec has been fully flushed, and there will be
2518  * no more output frames
2519  * @retval AVERROR(EINVAL) codec not opened, or it is an encoder without the
2520  * @ref AV_CODEC_FLAG_RECON_FRAME flag enabled
2521  * @retval "other negative error code" legitimate decoding errors
2522  */
2524 
2525 /**
2526  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
2527  * to retrieve buffered output packets.
2528  *
2529  * @param avctx codec context
2530  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
2531  * Ownership of the frame remains with the caller, and the
2532  * encoder will not write to the frame. The encoder may create
2533  * a reference to the frame data (or copy it if the frame is
2534  * not reference-counted).
2535  * It can be NULL, in which case it is considered a flush
2536  * packet. This signals the end of the stream. If the encoder
2537  * still has packets buffered, it will return them after this
2538  * call. Once flushing mode has been entered, additional flush
2539  * packets are ignored, and sending frames will return
2540  * AVERROR_EOF.
2541  *
2542  * For audio:
2543  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
2544  * can have any number of samples.
2545  * If it is not set, frame->nb_samples must be equal to
2546  * avctx->frame_size for all frames except the last.
2547  * The final frame may be smaller than avctx->frame_size.
2548  * @retval 0 success
2549  * @retval AVERROR(EAGAIN) input is not accepted in the current state - user must
2550  * read output with avcodec_receive_packet() (once all
2551  * output is read, the packet should be resent, and the
2552  * call will not fail with EAGAIN).
2553  * @retval AVERROR_EOF the encoder has been flushed, and no new frames can
2554  * be sent to it
2555  * @retval AVERROR(EINVAL) codec not opened, it is a decoder, or requires flush
2556  * @retval AVERROR(ENOMEM) failed to add packet to internal queue, or similar
2557  * @retval "another negative error code" legitimate encoding errors
2558  */
2559 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
2560 
2561 /**
2562  * Read encoded data from the encoder.
2563  *
2564  * @param avctx codec context
2565  * @param avpkt This will be set to a reference-counted packet allocated by the
2566  * encoder. Note that the function will always call
2567  * av_packet_unref(avpkt) before doing anything else.
2568  * @retval 0 success
2569  * @retval AVERROR(EAGAIN) output is not available in the current state - user must
2570  * try to send input
2571  * @retval AVERROR_EOF the encoder has been fully flushed, and there will be no
2572  * more output packets
2573  * @retval AVERROR(EINVAL) codec not opened, or it is a decoder
2574  * @retval "another negative error code" legitimate encoding errors
2575  */
2576 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
2577 
2578 /**
2579  * Create and return a AVHWFramesContext with values adequate for hardware
2580  * decoding. This is meant to get called from the get_format callback, and is
2581  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
2582  * This API is for decoding with certain hardware acceleration modes/APIs only.
2583  *
2584  * The returned AVHWFramesContext is not initialized. The caller must do this
2585  * with av_hwframe_ctx_init().
2586  *
2587  * Calling this function is not a requirement, but makes it simpler to avoid
2588  * codec or hardware API specific details when manually allocating frames.
2589  *
2590  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
2591  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
2592  * it unnecessary to call this function or having to care about
2593  * AVHWFramesContext initialization at all.
2594  *
2595  * There are a number of requirements for calling this function:
2596  *
2597  * - It must be called from get_format with the same avctx parameter that was
2598  * passed to get_format. Calling it outside of get_format is not allowed, and
2599  * can trigger undefined behavior.
2600  * - The function is not always supported (see description of return values).
2601  * Even if this function returns successfully, hwaccel initialization could
2602  * fail later. (The degree to which implementations check whether the stream
2603  * is actually supported varies. Some do this check only after the user's
2604  * get_format callback returns.)
2605  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
2606  * user decides to use a AVHWFramesContext prepared with this API function,
2607  * the user must return the same hw_pix_fmt from get_format.
2608  * - The device_ref passed to this function must support the given hw_pix_fmt.
2609  * - After calling this API function, it is the user's responsibility to
2610  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
2611  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
2612  * before returning from get_format (this is implied by the normal
2613  * AVCodecContext.hw_frames_ctx API rules).
2614  * - The AVHWFramesContext parameters may change every time time get_format is
2615  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
2616  * you are inherently required to go through this process again on every
2617  * get_format call.
2618  * - It is perfectly possible to call this function without actually using
2619  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
2620  * previously initialized AVHWFramesContext, and calling this API function
2621  * only to test whether the required frame parameters have changed.
2622  * - Fields that use dynamically allocated values of any kind must not be set
2623  * by the user unless setting them is explicitly allowed by the documentation.
2624  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
2625  * the new free callback must call the potentially set previous free callback.
2626  * This API call may set any dynamically allocated fields, including the free
2627  * callback.
2628  *
2629  * The function will set at least the following fields on AVHWFramesContext
2630  * (potentially more, depending on hwaccel API):
2631  *
2632  * - All fields set by av_hwframe_ctx_alloc().
2633  * - Set the format field to hw_pix_fmt.
2634  * - Set the sw_format field to the most suited and most versatile format. (An
2635  * implication is that this will prefer generic formats over opaque formats
2636  * with arbitrary restrictions, if possible.)
2637  * - Set the width/height fields to the coded frame size, rounded up to the
2638  * API-specific minimum alignment.
2639  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
2640  * field to the number of maximum reference surfaces possible with the codec,
2641  * plus 1 surface for the user to work (meaning the user can safely reference
2642  * at most 1 decoded surface at a time), plus additional buffering introduced
2643  * by frame threading. If the hwaccel does not require pre-allocation, the
2644  * field is left to 0, and the decoder will allocate new surfaces on demand
2645  * during decoding.
2646  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
2647  * hardware API.
2648  *
2649  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
2650  * with basic frame parameters set.
2651  *
2652  * The function is stateless, and does not change the AVCodecContext or the
2653  * device_ref AVHWDeviceContext.
2654  *
2655  * @param avctx The context which is currently calling get_format, and which
2656  * implicitly contains all state needed for filling the returned
2657  * AVHWFramesContext properly.
2658  * @param device_ref A reference to the AVHWDeviceContext describing the device
2659  * which will be used by the hardware decoder.
2660  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
2661  * @param out_frames_ref On success, set to a reference to an _uninitialized_
2662  * AVHWFramesContext, created from the given device_ref.
2663  * Fields will be set to values required for decoding.
2664  * Not changed if an error is returned.
2665  * @return zero on success, a negative value on error. The following error codes
2666  * have special semantics:
2667  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
2668  * is always manual, or it is a decoder which does not
2669  * support setting AVCodecContext.hw_frames_ctx at all,
2670  * or it is a software format.
2671  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
2672  * this configuration, or the device_ref is not supported
2673  * for the hwaccel referenced by hw_pix_fmt.
2674  */
2676  AVBufferRef *device_ref,
2678  AVBufferRef **out_frames_ref);
2679 
2680 
2681 
2682 /**
2683  * @defgroup lavc_parsing Frame parsing
2684  * @{
2685  */
2686 
2689  AV_PICTURE_STRUCTURE_TOP_FIELD, ///< coded as top field
2690  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, ///< coded as bottom field
2691  AV_PICTURE_STRUCTURE_FRAME, ///< coded as frame
2692 };
2693 
2694 typedef struct AVCodecParserContext {
2695  void *priv_data;
2696  const struct AVCodecParser *parser;
2697  int64_t frame_offset; /* offset of the current frame */
2698  int64_t cur_offset; /* current offset
2699  (incremented by each av_parser_parse()) */
2700  int64_t next_frame_offset; /* offset of the next frame */
2701  /* video info */
2702  int pict_type; /* XXX: Put it back in AVCodecContext. */
2703  /**
2704  * This field is used for proper frame duration computation in lavf.
2705  * It signals, how much longer the frame duration of the current frame
2706  * is compared to normal frame duration.
2707  *
2708  * frame_duration = (1 + repeat_pict) * time_base
2709  *
2710  * It is used by codecs like H.264 to display telecined material.
2711  */
2712  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
2713  int64_t pts; /* pts of the current frame */
2714  int64_t dts; /* dts of the current frame */
2715 
2716  /* private data */
2717  int64_t last_pts;
2718  int64_t last_dts;
2720 
2721 #define AV_PARSER_PTS_NB 4
2726 
2727  int flags;
2728 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
2729 #define PARSER_FLAG_ONCE 0x0002
2730 /// Set if the parser has a valid file offset
2731 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
2732 #define PARSER_FLAG_USE_CODEC_TS 0x1000
2733 
2734  int64_t offset; ///< byte offset from starting packet start
2736 
2737  /**
2738  * Set by parser to 1 for key frames and 0 for non-key frames.
2739  * It is initialized to -1, so if the parser doesn't set this flag,
2740  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
2741  * will be used.
2742  */
2744 
2745  // Timestamp generation support:
2746  /**
2747  * Synchronization point for start of timestamp generation.
2748  *
2749  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
2750  * (default).
2751  *
2752  * For example, this corresponds to presence of H.264 buffering period
2753  * SEI message.
2754  */
2756 
2757  /**
2758  * Offset of the current timestamp against last timestamp sync point in
2759  * units of AVCodecContext.time_base.
2760  *
2761  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2762  * contain a valid timestamp offset.
2763  *
2764  * Note that the timestamp of sync point has usually a nonzero
2765  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
2766  * the next frame after timestamp sync point will be usually 1.
2767  *
2768  * For example, this corresponds to H.264 cpb_removal_delay.
2769  */
2771 
2772  /**
2773  * Presentation delay of current frame in units of AVCodecContext.time_base.
2774  *
2775  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
2776  * contain valid non-negative timestamp delta (presentation time of a frame
2777  * must not lie in the past).
2778  *
2779  * This delay represents the difference between decoding and presentation
2780  * time of the frame.
2781  *
2782  * For example, this corresponds to H.264 dpb_output_delay.
2783  */
2785 
2786  /**
2787  * Position of the packet in file.
2788  *
2789  * Analogous to cur_frame_pts/dts
2790  */
2792 
2793  /**
2794  * Byte position of currently parsed frame in stream.
2795  */
2796  int64_t pos;
2797 
2798  /**
2799  * Previous frame byte position.
2800  */
2801  int64_t last_pos;
2802 
2803  /**
2804  * Duration of the current frame.
2805  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
2806  * For all other types, this is in units of AVCodecContext.time_base.
2807  */
2809 
2811 
2812  /**
2813  * Indicate whether a picture is coded as a frame, top field or bottom field.
2814  *
2815  * For example, H.264 field_pic_flag equal to 0 corresponds to
2816  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
2817  * equal to 1 and bottom_field_flag equal to 0 corresponds to
2818  * AV_PICTURE_STRUCTURE_TOP_FIELD.
2819  */
2821 
2822  /**
2823  * Picture number incremented in presentation or output order.
2824  * This field may be reinitialized at the first picture of a new sequence.
2825  *
2826  * For example, this corresponds to H.264 PicOrderCnt.
2827  */
2829 
2830  /**
2831  * Dimensions of the decoded video intended for presentation.
2832  */
2833  int width;
2834  int height;
2835 
2836  /**
2837  * Dimensions of the coded video.
2838  */
2841 
2842  /**
2843  * The format of the coded data, corresponds to enum AVPixelFormat for video
2844  * and for enum AVSampleFormat for audio.
2845  *
2846  * Note that a decoder can have considerable freedom in how exactly it
2847  * decodes the data, so the format reported here might be different from the
2848  * one returned by a decoder.
2849  */
2850  int format;
2852 
2853 typedef struct AVCodecParser {
2854  int codec_ids[7]; /* several codec IDs are permitted */
2857  /* This callback never returns an error, a negative value means that
2858  * the frame start was in a previous packet. */
2860  AVCodecContext *avctx,
2861  const uint8_t **poutbuf, int *poutbuf_size,
2862  const uint8_t *buf, int buf_size);
2864  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
2865 } AVCodecParser;
2866 
2867 /**
2868  * Iterate over all registered codec parsers.
2869  *
2870  * @param opaque a pointer where libavcodec will store the iteration state. Must
2871  * point to NULL to start the iteration.
2872  *
2873  * @return the next registered codec parser or NULL when the iteration is
2874  * finished
2875  */
2876 const AVCodecParser *av_parser_iterate(void **opaque);
2877 
2879 
2880 /**
2881  * Parse a packet.
2882  *
2883  * @param s parser context.
2884  * @param avctx codec context.
2885  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
2886  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
2887  * @param buf input buffer.
2888  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
2889  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
2890  To signal EOF, this should be 0 (so that the last frame
2891  can be output).
2892  * @param pts input presentation timestamp.
2893  * @param dts input decoding timestamp.
2894  * @param pos input byte position in stream.
2895  * @return the number of bytes of the input bitstream used.
2896  *
2897  * Example:
2898  * @code
2899  * while(in_len){
2900  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
2901  * in_data, in_len,
2902  * pts, dts, pos);
2903  * in_data += len;
2904  * in_len -= len;
2905  *
2906  * if(size)
2907  * decode_frame(data, size);
2908  * }
2909  * @endcode
2910  */
2912  AVCodecContext *avctx,
2913  uint8_t **poutbuf, int *poutbuf_size,
2914  const uint8_t *buf, int buf_size,
2915  int64_t pts, int64_t dts,
2916  int64_t pos);
2917 
2919 
2920 /**
2921  * @}
2922  * @}
2923  */
2924 
2925 /**
2926  * @addtogroup lavc_encoding
2927  * @{
2928  */
2929 
2930 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
2931  const AVSubtitle *sub);
2932 
2933 
2934 /**
2935  * @}
2936  */
2937 
2938 /**
2939  * @defgroup lavc_misc Utility functions
2940  * @ingroup libavc
2941  *
2942  * Miscellaneous utility functions related to both encoding and decoding
2943  * (or neither).
2944  * @{
2945  */
2946 
2947 /**
2948  * @defgroup lavc_misc_pixfmt Pixel formats
2949  *
2950  * Functions for working with pixel formats.
2951  * @{
2952  */
2953 
2954 /**
2955  * Return a value representing the fourCC code associated to the
2956  * pixel format pix_fmt, or 0 if no associated fourCC code can be
2957  * found.
2958  */
2960 
2961 /**
2962  * Find the best pixel format to convert to given a certain source pixel
2963  * format. When converting from one pixel format to another, information loss
2964  * may occur. For example, when converting from RGB24 to GRAY, the color
2965  * information will be lost. Similarly, other losses occur when converting from
2966  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
2967  * the given pixel formats should be used to suffer the least amount of loss.
2968  * The pixel formats from which it chooses one, are determined by the
2969  * pix_fmt_list parameter.
2970  *
2971  *
2972  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
2973  * @param[in] src_pix_fmt source pixel format
2974  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
2975  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
2976  * @return The best pixel format to convert to or -1 if none was found.
2977  */
2978 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
2979  enum AVPixelFormat src_pix_fmt,
2980  int has_alpha, int *loss_ptr);
2981 
2983 
2984 /**
2985  * @}
2986  */
2987 
2988 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
2989 
2990 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
2991 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
2992 //FIXME func typedef
2993 
2994 /**
2995  * Fill AVFrame audio data and linesize pointers.
2996  *
2997  * The buffer buf must be a preallocated buffer with a size big enough
2998  * to contain the specified samples amount. The filled AVFrame data
2999  * pointers will point to this buffer.
3000  *
3001  * AVFrame extended_data channel pointers are allocated if necessary for
3002  * planar audio.
3003  *
3004  * @param frame the AVFrame
3005  * frame->nb_samples must be set prior to calling the
3006  * function. This function fills in frame->data,
3007  * frame->extended_data, frame->linesize[0].
3008  * @param nb_channels channel count
3009  * @param sample_fmt sample format
3010  * @param buf buffer to use for frame data
3011  * @param buf_size size of buffer
3012  * @param align plane size sample alignment (0 = default)
3013  * @return >=0 on success, negative error code on failure
3014  * @todo return the size in bytes required to store the samples in
3015  * case of success, at the next libavutil bump
3016  */
3017 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
3018  enum AVSampleFormat sample_fmt, const uint8_t *buf,
3019  int buf_size, int align);
3020 
3021 /**
3022  * Reset the internal codec state / flush internal buffers. Should be called
3023  * e.g. when seeking or when switching to a different stream.
3024  *
3025  * @note for decoders, this function just releases any references the decoder
3026  * might keep internally, but the caller's references remain valid.
3027  *
3028  * @note for encoders, this function will only do something if the encoder
3029  * declares support for AV_CODEC_CAP_ENCODER_FLUSH. When called, the encoder
3030  * will drain any remaining packets, and can then be re-used for a different
3031  * stream (as opposed to sending a null frame which will leave the encoder
3032  * in a permanent EOF state after draining). This can be desirable if the
3033  * cost of tearing down and replacing the encoder instance is high.
3034  */
3036 
3037 /**
3038  * Return audio frame duration.
3039  *
3040  * @param avctx codec context
3041  * @param frame_bytes size of the frame, or 0 if unknown
3042  * @return frame duration, in samples, if known. 0 if not able to
3043  * determine.
3044  */
3045 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
3046 
3047 /* memory */
3048 
3049 /**
3050  * Same behaviour av_fast_malloc but the buffer has additional
3051  * AV_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
3052  *
3053  * In addition the whole buffer will initially and after resizes
3054  * be 0-initialized so that no uninitialized data will ever appear.
3055  */
3056 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
3057 
3058 /**
3059  * Same behaviour av_fast_padded_malloc except that buffer will always
3060  * be 0-initialized after call.
3061  */
3062 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
3063 
3064 /**
3065  * @return a positive value if s is open (i.e. avcodec_open2() was called on it
3066  * with no corresponding avcodec_close()), 0 otherwise.
3067  */
3069 
3070 /**
3071  * @}
3072  */
3073 
3074 #endif /* AVCODEC_AVCODEC_H */
AVSubtitle
Definition: avcodec.h:2214
func
int(* func)(AVBPrint *dst, const char *in, const char *arg)
Definition: jacosubdec.c:68
avcodec_encode_subtitle
int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size, const AVSubtitle *sub)
Definition: encode.c:190
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1077
AVCodecContext::hwaccel
const struct AVHWAccel * hwaccel
Hardware accelerator in use.
Definition: avcodec.h:1427
AVCodec
AVCodec.
Definition: codec.h:187
AVCodecContext::hwaccel_context
void * hwaccel_context
Legacy hardware accelerator context.
Definition: avcodec.h:1451
hw_pix_fmt
static enum AVPixelFormat hw_pix_fmt
Definition: hw_decode.c:45
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
AVCodecParserContext::pts
int64_t pts
Definition: avcodec.h:2713
AVCodecContext::log_level_offset
int log_level_offset
Definition: avcodec.h:451
AVCodecContext::keyint_min
int keyint_min
minimum GOP size
Definition: avcodec.h:1024
avcodec_receive_packet
int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt)
Read encoded data from the encoder.
Definition: encode.c:540
AVCodecContext::workaround_bugs
int workaround_bugs
Work around bugs in encoders which sometimes cannot be detected automatically.
Definition: avcodec.h:1349
AVSubtitle::rects
AVSubtitleRect ** rects
Definition: avcodec.h:2219
AVCodecContext::get_format
enum AVPixelFormat(* get_format)(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Callback to negotiate the pixel format.
Definition: avcodec.h:787
AVCodecParserContext::dts_sync_point
int dts_sync_point
Synchronization point for start of timestamp generation.
Definition: avcodec.h:2755
AVCodecContext::audio_service_type
enum AVAudioServiceType audio_service_type
Type of service that the audio stream conveys.
Definition: avcodec.h:1097
AVCodecContext::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: avcodec.h:685
AVColorTransferCharacteristic
AVColorTransferCharacteristic
Color Transfer Characteristic.
Definition: pixfmt.h:580
AVCodecContext::av_class
const AVClass * av_class
information on struct for av_log
Definition: avcodec.h:450
AVCodecParserContext::pict_type
int pict_type
Definition: avcodec.h:2702
AVFieldOrder
AVFieldOrder
Definition: defs.h:198
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1050
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1299
AVCodecParserContext::output_picture_number
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:2828
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:47
AVHWAccel::type
enum AVMediaType type
Type of codec implemented by the hardware accelerator.
Definition: avcodec.h:2088
AV_PICTURE_STRUCTURE_UNKNOWN
@ AV_PICTURE_STRUCTURE_UNKNOWN
unknown
Definition: avcodec.h:2688
AVCodecParserContext::duration
int duration
Duration of the current frame.
Definition: avcodec.h:2808
AVCodecContext::err_recognition
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1420
avcodec_string
void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode)
Definition: avcodec.c:481
AVCodecContext::codec_descriptor
const struct AVCodecDescriptor * codec_descriptor
AVCodecDescriptor.
Definition: avcodec.h:1861
rational.h
AVCodecContext::coded_side_data
AVPacketSideData * coded_side_data
Additional data associated with the entire coded stream.
Definition: avcodec.h:1915
AVSubtitleRect
Definition: avcodec.h:2187
AVSubtitle::num_rects
unsigned num_rects
Definition: avcodec.h:2218
av_parser_iterate
const AVCodecParser * av_parser_iterate(void **opaque)
Iterate over all registered codec parsers.
Definition: parsers.c:86
AVCodecContext::intra_matrix
uint16_t * intra_matrix
custom intra quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:974
AVCodecContext::mv0_threshold
int mv0_threshold
Note: Value depends upon the compare function used for fullpel ME.
Definition: avcodec.h:1038
AVCodecContext::lumi_masking
float lumi_masking
luminance masking (0-> disabled)
Definition: avcodec.h:834
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVCodecContext::color_trc
enum AVColorTransferCharacteristic color_trc
Color Transfer Characteristic.
Definition: avcodec.h:678
AVPacketSideData
This structure stores auxiliary information for decoding, presenting, or otherwise processing the cod...
Definition: packet.h:373
AVCodecParserContext::pts_dts_delta
int pts_dts_delta
Presentation delay of current frame in units of AVCodecContext.time_base.
Definition: avcodec.h:2784
AVCodecContext::field_order
enum AVFieldOrder field_order
Field order.
Definition: avcodec.h:708
AVHWAccel::capabilities
int capabilities
Hardware accelerated codec capabilities.
Definition: avcodec.h:2108
version_major.h
AVCodecContext::b_quant_offset
float b_quant_offset
qscale offset between IP and B-frames
Definition: avcodec.h:811
AVCodecParserContext::height
int height
Definition: avcodec.h:2834
avcodec_align_dimensions
void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height)
Modify width and height values so that they will result in a memory buffer that is acceptable for the...
Definition: utils.c:351
RcOverride::qscale
int qscale
Definition: avcodec.h:207
AVCodecContext::subtitle_header
uint8_t * subtitle_header
Definition: avcodec.h:1891
AVSubtitleRect::linesize
int linesize[4]
Definition: avcodec.h:2199
AVCodecParserContext::cur_frame_start_index
int cur_frame_start_index
Definition: avcodec.h:2722
AVCodecContext::me_pre_cmp
int me_pre_cmp
motion estimation prepass comparison function
Definition: avcodec.h:932
AVDictionary
Definition: dict.c:34
AVColorPrimaries
AVColorPrimaries
Chromaticity coordinates of the source primaries.
Definition: pixfmt.h:555
avcodec_default_get_format
enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat *fmt)
Definition: decode.c:1000
avcodec_find_best_pix_fmt_of_list
enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list, enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr)
Find the best pixel format to convert to given a certain source pixel format.
Definition: imgconvert.c:31
AVCodecContext::mb_decision
int mb_decision
macroblock decision mode
Definition: avcodec.h:962
avcodec_is_open
int avcodec_is_open(AVCodecContext *s)
Definition: avcodec.c:676
AVCodecContext::qmax
int qmax
maximum quantizer
Definition: avcodec.h:1263
AVCodecParserContext::coded_width
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:2839
AVCodecContext::delay
int delay
Codec delay.
Definition: avcodec.h:601
AVCodecContext::me_subpel_quality
int me_subpel_quality
subpel ME quality
Definition: avcodec.h:946
AVCodecContext::mb_cmp
int mb_cmp
macroblock comparison function (not supported yet)
Definition: avcodec.h:888
AVPictureStructure
AVPictureStructure
Definition: avcodec.h:2687
avcodec_pix_fmt_to_codec_tag
unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt)
Return a value representing the fourCC code associated to the pixel format pix_fmt,...
Definition: raw.c:308
SUBTITLE_ASS
@ SUBTITLE_ASS
Formatted text, the ass field must be set by the decoder and is authoritative.
Definition: avcodec.h:2182
AVCodecParserContext::parser
const struct AVCodecParser * parser
Definition: avcodec.h:2696
AVCodecContext::framerate
AVRational framerate
Definition: avcodec.h:560
AVCodecContext::skip_top
int skip_top
Number of macroblock rows at the top which are skipped.
Definition: avcodec.h:1840
AVCodecParserContext::offset
int64_t offset
byte offset from starting packet start
Definition: avcodec.h:2734
AVHWAccel
Definition: avcodec.h:2075
AVCodecParserContext::key_frame
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:2743
AVCodecContext::skip_idct
enum AVDiscard skip_idct
Skip IDCT/dequantization for selected frames.
Definition: avcodec.h:1812
AVCodecContext::i_quant_factor
float i_quant_factor
qscale factor between P- and I-frames If > 0 then the last P-frame quantizer will be used (q = lastp_...
Definition: avcodec.h:820
AVCodecContext::nsse_weight
int nsse_weight
noise vs.
Definition: avcodec.h:869
AVCodecContext::codec
const struct AVCodec * codec
Definition: avcodec.h:454
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:1065
AVCodecContext::skip_frame
enum AVDiscard skip_frame
Skip decoding for selected frames.
Definition: avcodec.h:1819
AVCodecContext::thread_count
int thread_count
thread count is used to decide how many independent tasks should be passed to execute()
Definition: avcodec.h:1582
samplefmt.h
AVSubtitleRect::x
int x
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2188
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1122
AVCodecContext::refs
int refs
number of reference frames
Definition: avcodec.h:715
avcodec_default_execute2
int avcodec_default_execute2(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2, int, int), void *arg, int *ret, int count)
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:502
AVCodecContext::bit_rate_tolerance
int bit_rate_tolerance
number of bits the bitstream is allowed to diverge from the reference.
Definition: avcodec.h:1231
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
AVCodecContext::dct_algo
int dct_algo
DCT algorithm, see FF_DCT_* below.
Definition: avcodec.h:1534
av_parser_init
AVCodecParserContext * av_parser_init(int codec_id)
Definition: parser.c:32
pts
static int64_t pts
Definition: transcode_aac.c:643
AVCodecContext::coded_height
int coded_height
Definition: avcodec.h:633
AVCodecContext::max_samples
int64_t max_samples
The number of samples per frame to maximally accept.
Definition: avcodec.h:1977
codec.h
AVCodecParserContext::dts
int64_t dts
Definition: avcodec.h:2714
AVSubtitleRect::ass
char * ass
0 terminated ASS/SSA compatible event line.
Definition: avcodec.h:2211
avsubtitle_free
void avsubtitle_free(AVSubtitle *sub)
Free all allocated data in the given subtitle struct.
Definition: avcodec.c:379
AVCodecContext::get_buffer2
int(* get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags)
This callback is called at the beginning of each frame to get data buffer(s) for it.
Definition: avcodec.h:1222
avcodec_decode_subtitle2
int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub, int *got_sub_ptr, const AVPacket *avpkt)
Decode a subtitle message.
Definition: decode.c:929
AV_PICTURE_STRUCTURE_FRAME
@ AV_PICTURE_STRUCTURE_FRAME
coded as frame
Definition: avcodec.h:2691
RcOverride::quality_factor
float quality_factor
Definition: avcodec.h:208
AVCodecContext::color_primaries
enum AVColorPrimaries color_primaries
Chromaticity coordinates of the source primaries.
Definition: avcodec.h:671
AVCodecParserContext::cur_frame_end
int64_t cur_frame_end[AV_PARSER_PTS_NB]
Definition: avcodec.h:2735
pkt
AVPacket * pkt
Definition: movenc.c:59
AVCodecContext::rc_initial_buffer_occupancy
int rc_initial_buffer_occupancy
Number of bits which should be loaded into the rc buffer before decoding starts.
Definition: avcodec.h:1320
codec_id.h
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:524
AVCodecContext::has_b_frames
int has_b_frames
Size of the frame reordering buffer in the decoder.
Definition: avcodec.h:723
AVCodecContext::side_data_prefer_packet
int * side_data_prefer_packet
Decoding only.
Definition: avcodec.h:2060
avcodec_alloc_context3
AVCodecContext * avcodec_alloc_context3(const AVCodec *codec)
Allocate an AVCodecContext and set its fields to default values.
Definition: options.c:149
width
#define width
AVCodecDescriptor
This struct describes the properties of a single codec described by an AVCodecID.
Definition: codec_desc.h:38
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVCodecContext::stats_in
char * stats_in
pass2 encoding statistics input buffer Concatenated stuff from stats_out of pass1 should be placed he...
Definition: avcodec.h:1342
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:1239
AVCodecParserContext::fetch_timestamp
int fetch_timestamp
Definition: avcodec.h:2719
RcOverride
Definition: avcodec.h:204
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demux_decode.c:41
AVCodecParserContext::last_pts
int64_t last_pts
Definition: avcodec.h:2717
AVSubtitleRect::y
int y
top left corner of pict, undefined when pict is not set
Definition: avcodec.h:2189
AVCodecContext::error_concealment
int error_concealment
error concealment flags
Definition: avcodec.h:1386
avcodec_receive_frame
int avcodec_receive_frame(AVCodecContext *avctx, AVFrame *frame)
Return decoded output data from a decoder or encoder (when the AV_CODEC_FLAG_RECON_FRAME flag is used...
Definition: avcodec.c:681
AVSubtitleType
AVSubtitleType
Definition: avcodec.h:2167
avcodec_close
attribute_deprecated int avcodec_close(AVCodecContext *avctx)
Close a given AVCodecContext and free all the data associated with it (but not the AVCodecContext its...
Definition: avcodec.c:469
AVCodecContext::thread_type
int thread_type
Which multithreading methods to use.
Definition: avcodec.h:1592
AVCodecContext::bits_per_raw_sample
int bits_per_raw_sample
Bits per sample/pixel of internal libavcodec pixel/sample format.
Definition: avcodec.h:1574
avcodec_fill_audio_frame
int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels, enum AVSampleFormat sample_fmt, const uint8_t *buf, int buf_size, int align)
Fill AVFrame audio data and linesize pointers.
Definition: utils.c:366
RcOverride::start_frame
int start_frame
Definition: avcodec.h:205
AVCodecParserContext::format
int format
The format of the coded data, corresponds to enum AVPixelFormat for video and for enum AVSampleFormat...
Definition: avcodec.h:2850
AVSubtitle::pts
int64_t pts
Same as packet pts, in AV_TIME_BASE.
Definition: avcodec.h:2220
avcodec_align_dimensions2
void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height, int linesize_align[AV_NUM_DATA_POINTERS])
Modify width and height values so that they will result in a memory buffer that is acceptable for the...
Definition: utils.c:144
AVCodecContext::max_pixels
int64_t max_pixels
The number of pixels per image to maximally accept.
Definition: avcodec.h:1934
codec_id
enum AVCodecID codec_id
Definition: vaapi_decode.c:386
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1292
AVCodecContext::error
uint64_t error[AV_NUM_DATA_POINTERS]
error
Definition: avcodec.h:1527
AVSubtitleRect::text
char * text
0 terminated plain UTF-8 text
Definition: avcodec.h:2204
frame
static AVFrame * frame
Definition: demux_decode.c:54
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:455
AVCodecContext::p_masking
float p_masking
p block masking (0-> disabled)
Definition: avcodec.h:855
arg
const char * arg
Definition: jacosubdec.c:67
AVCodecParserContext::dts_ref_dts_delta
int dts_ref_dts_delta
Offset of the current timestamp against last timestamp sync point in units of AVCodecContext....
Definition: avcodec.h:2770
AVCodecParserContext::repeat_pict
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:2712
AV_PICTURE_STRUCTURE_BOTTOM_FIELD
@ AV_PICTURE_STRUCTURE_BOTTOM_FIELD
coded as bottom field
Definition: avcodec.h:2690
AVCodecContext::rc_buffer_size
int rc_buffer_size
decoder bitstream buffer size
Definition: avcodec.h:1277
AVCodecContext::sub_charenc
char * sub_charenc
Character encoding of the input subtitles file.
Definition: avcodec.h:1868
avcodec_parameters_to_context
int avcodec_parameters_to_context(AVCodecContext *codec, const struct AVCodecParameters *par)
Fill the codec context based on the values from the supplied codec parameters.
AVSubtitleRect::w
int w
width of pict, undefined when pict is not set
Definition: avcodec.h:2190
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
avcodec_get_class
const AVClass * avcodec_get_class(void)
Get the AVClass for AVCodecContext.
Definition: options.c:183
AVCodecContext::apply_cropping
int apply_cropping
Video decoding only.
Definition: avcodec.h:1961
AVCodecContext::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:695
AVCodecContext::slice_flags
int slice_flags
slice flags
Definition: avcodec.h:730
AVCodecParser::parser_close
void(* parser_close)(AVCodecParserContext *s)
Definition: avcodec.h:2863
avcodec_free_context
void avcodec_free_context(AVCodecContext **avctx)
Free the codec context and everything associated with it and write NULL to the provided pointer.
Definition: options.c:164
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVCodecContext::nb_coded_side_data
int nb_coded_side_data
Definition: avcodec.h:1916
AVCodecContext::qblur
float qblur
amount of qscale smoothing over time (0.0-1.0)
Definition: avcodec.h:1249
AV_PICTURE_STRUCTURE_TOP_FIELD
@ AV_PICTURE_STRUCTURE_TOP_FIELD
coded as top field
Definition: avcodec.h:2689
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:495
AVCodecParser::split
int(* split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2864
AVCodecContext::subtitle_header_size
int subtitle_header_size
Header containing style information for text subtitles.
Definition: avcodec.h:1890
AVSubtitleRect::data
uint8_t * data[4]
data+linesize for the bitmap of this subtitle.
Definition: avcodec.h:2198
AVCodecContext::trailing_padding
int trailing_padding
Audio only.
Definition: avcodec.h:1133
AVCodecContext::ildct_cmp
int ildct_cmp
interlaced DCT comparison function
Definition: avcodec.h:894
avcodec_license
const char * avcodec_license(void)
Return the libavcodec license.
Definition: version.c:46
AVCodecContext::rc_min_vbv_overflow_use
float rc_min_vbv_overflow_use
Ratecontrol attempt to use, at least, times the amount needed to prevent a vbv overflow.
Definition: avcodec.h:1313
avcodec_open2
int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Initialize the AVCodecContext to use the given AVCodec.
Definition: avcodec.c:128
AVCodecParserContext::flags
int flags
Definition: avcodec.h:2727
avcodec_version
unsigned avcodec_version(void)
Return the LIBAVCODEC_VERSION_INT constant.
Definition: version.c:31
AVCodecContext::me_cmp
int me_cmp
motion estimation comparison function
Definition: avcodec.h:876
AVCodecParserContext::picture_structure
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:2820
AVCodecContext::trellis
int trellis
trellis RD quantization
Definition: avcodec.h:1327
AVCodecContext::level
int level
Encoding level descriptor.
Definition: avcodec.h:1783
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVAudioServiceType
AVAudioServiceType
Definition: defs.h:222
avcodec_get_subtitle_rect_class
const AVClass * avcodec_get_subtitle_rect_class(void)
Get the AVClass for AVSubtitleRect.
Definition: options.c:208
AVCodecID
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: codec_id.h:49
AVCodecContext::temporal_cplx_masking
float temporal_cplx_masking
temporary complexity masking (0-> disabled)
Definition: avcodec.h:841
AVCodecContext::qcompress
float qcompress
amount of qscale change between easy & hard scenes (0.0-1.0)
Definition: avcodec.h:1248
AVCodecContext::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avcodec.h:544
AVCodecContext::lowres
int lowres
low resolution decoding, 1-> 1/2 size, 2->1/4 size
Definition: avcodec.h:1854
options
const OptionDef options[]
AVCodecContext::stats_out
char * stats_out
pass1 encoding statistics output buffer
Definition: avcodec.h:1334
AVCodecContext::rc_override
RcOverride * rc_override
Definition: avcodec.h:1285
AVCodecContext::flags2
int flags2
AV_CODEC_FLAG2_*.
Definition: avcodec.h:509
AVMediaType
AVMediaType
Definition: avutil.h:199
AVCodecParserContext::frame_offset
int64_t frame_offset
Definition: avcodec.h:2697
AVCodecContext::gop_size
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:1031
AVCodecParser::codec_ids
int codec_ids[7]
Definition: avcodec.h:2854
AVCodecContext::extra_hw_frames
int extra_hw_frames
Video decoding only.
Definition: avcodec.h:1520
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:303
AVCodecParserContext::next_frame_offset
int64_t next_frame_offset
Definition: avcodec.h:2700
AVCodecParserContext::cur_frame_offset
int64_t cur_frame_offset[AV_PARSER_PTS_NB]
Definition: avcodec.h:2723
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1057
AVCodecContext::pkt_timebase
AVRational pkt_timebase
Timebase in which pkt_dts/pts and AVPacket.dts/pts are expressed.
Definition: avcodec.h:551
size
int size
Definition: twinvq_data.h:10344
AVCodecParserContext::width
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:2833
AV_NUM_DATA_POINTERS
#define AV_NUM_DATA_POINTERS
Definition: frame.h:341
AVCodecContext::me_range
int me_range
maximum motion estimation search range in subpel units If 0 then no limit.
Definition: avcodec.h:955
AVCodecParser::parser_parse
int(* parser_parse)(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: avcodec.h:2859
AVCodecContext::skip_alpha
int skip_alpha
Skip processing alpha if supported by codec.
Definition: avcodec.h:1833
AVCodecContext::chroma_intra_matrix
uint16_t * chroma_intra_matrix
custom intra quantization matrix
Definition: avcodec.h:990
AVCodecContext::skip_bottom
int skip_bottom
Number of macroblock rows at the bottom which are skipped.
Definition: avcodec.h:1847
AVCodecContext::last_predictor_count
int last_predictor_count
amount of previous MV predictors (2a+1 x 2a+1 square)
Definition: avcodec.h:925
AVSubtitle::end_display_time
uint32_t end_display_time
Definition: avcodec.h:2217
frame.h
AVSubtitleRect::type
enum AVSubtitleType type
Definition: avcodec.h:2202
SUBTITLE_TEXT
@ SUBTITLE_TEXT
Plain text, the text field must be set by the decoder and is authoritative.
Definition: avcodec.h:2176
buffer.h
align
static const uint8_t *BS_FUNC() align(BSCTX *bc)
Skip bits to a byte boundary.
Definition: bitstream_template.h:411
attribute_deprecated
#define attribute_deprecated
Definition: attributes.h:104
SUBTITLE_NONE
@ SUBTITLE_NONE
Definition: avcodec.h:2168
encode
static void encode(AVCodecContext *ctx, AVFrame *frame, AVPacket *pkt, FILE *output)
Definition: encode_audio.c:94
AVCodecContext::me_sub_cmp
int me_sub_cmp
subpixel motion estimation comparison function
Definition: avcodec.h:882
height
#define height
avcodec_default_execute
int avcodec_default_execute(AVCodecContext *c, int(*func)(AVCodecContext *c2, void *arg2), void *arg, int *ret, int count, int size)
Definition: avcodec.c:57
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
AVCodecContext::request_sample_fmt
enum AVSampleFormat request_sample_fmt
desired sample format
Definition: avcodec.h:1105
attributes.h
AVCodecInternal
Definition: internal.h:49
AVCodecContext::skip_loop_filter
enum AVDiscard skip_loop_filter
Skip loop filtering for selected frames.
Definition: avcodec.h:1805
AVCodecContext::nb_side_data_prefer_packet
unsigned nb_side_data_prefer_packet
Number of entries in side_data_prefer_packet.
Definition: avcodec.h:2064
SUBTITLE_BITMAP
@ SUBTITLE_BITMAP
A bitmap, pict will be set.
Definition: avcodec.h:2170
AVCodecContext::b_quant_factor
float b_quant_factor
qscale factor between IP and B-frames If > 0 then the last P-frame quantizer will be used (q= lastp_q...
Definition: avcodec.h:804
AVCodecParserContext::cur_frame_pts
int64_t cur_frame_pts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2724
AVChromaLocation
AVChromaLocation
Location of chroma samples.
Definition: pixfmt.h:702
AVCodecParserContext::cur_frame_pos
int64_t cur_frame_pos[AV_PARSER_PTS_NB]
Position of the packet in file.
Definition: avcodec.h:2791
AVHWAccel::name
const char * name
Name of the hardware accelerated codec.
Definition: avcodec.h:2081
AVSubtitleRect::flags
int flags
Definition: avcodec.h:2201
AVCodecContext::bits_per_coded_sample
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:1567
avcodec_default_get_buffer2
int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags)
The default callback for AVCodecContext.get_buffer2().
Definition: get_buffer.c:254
avcodec_send_packet
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
Supply raw packet data as input to a decoder.
Definition: decode.c:674
AVCodecParserContext::pos
int64_t pos
Byte position of currently parsed frame in stream.
Definition: avcodec.h:2796
AVSubtitle::format
uint16_t format
Definition: avcodec.h:2215
log.h
RcOverride::end_frame
int end_frame
Definition: avcodec.h:206
AVCodecContext::properties
unsigned properties
Properties of the stream that gets decoded.
Definition: avcodec.h:1795
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:523
AVSubtitleRect::nb_colors
int nb_colors
number of colors in pict, undefined when pict is not set
Definition: avcodec.h:2192
packet.h
AVCodecContext::intra_dc_precision
int intra_dc_precision
precision of the intra DC coefficient - 8
Definition: avcodec.h:997
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:609
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1090
AVCodecContext::hwaccel_flags
int hwaccel_flags
Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated decoding (if active).
Definition: avcodec.h:1506
AVCodecParserContext::cur_offset
int64_t cur_offset
Definition: avcodec.h:2698
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
av_fast_padded_malloc
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:52
AVCodecParser::parser_init
int(* parser_init)(AVCodecParserContext *s)
Definition: avcodec.h:2856
AVCodecContext::dia_size
int dia_size
ME diamond size & shape.
Definition: avcodec.h:918
AVCodecContext::dump_separator
uint8_t * dump_separator
dump format separator.
Definition: avcodec.h:1899
AVCodecContext::mb_lmin
int mb_lmin
minimum MB Lagrange multiplier
Definition: avcodec.h:1004
av_get_audio_frame_duration
int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
Return audio frame duration.
Definition: utils.c:783
AVCodecContext::idct_algo
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:1547
AVCodecContext::hw_device_ctx
AVBufferRef * hw_device_ctx
A reference to the AVHWDeviceContext describing the device which will be used by a hardware encoder/d...
Definition: avcodec.h:1497
AVCodecContext::chroma_sample_location
enum AVChromaLocation chroma_sample_location
This defines the location of chroma samples.
Definition: avcodec.h:702
AVCodecContext::height
int height
Definition: avcodec.h:618
avcodec_send_frame
int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame)
Supply a raw video or audio frame to the encoder.
Definition: encode.c:507
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:657
AVCodecContext::hw_frames_ctx
AVBufferRef * hw_frames_ctx
A reference to the AVHWFramesContext describing the input (for encoding) or output (decoding) frames.
Definition: avcodec.h:1475
AVCodecParserContext
Definition: avcodec.h:2694
AVCodecContext::sub_charenc_mode
int sub_charenc_mode
Subtitles character encoding mode.
Definition: avcodec.h:1876
AVCodecContext::frame_num
int64_t frame_num
Frame counter, set by libavcodec.
Definition: avcodec.h:2030
avcodec_get_hw_frames_parameters
int avcodec_get_hw_frames_parameters(AVCodecContext *avctx, AVBufferRef *device_ref, enum AVPixelFormat hw_pix_fmt, AVBufferRef **out_frames_ref)
Create and return a AVHWFramesContext with values adequate for hardware decoding.
Definition: decode.c:1114
ret
ret
Definition: filter_design.txt:187
AVSubtitleRect::h
int h
height of pict, undefined when pict is not set
Definition: avcodec.h:2191
AVCodecContext::block_align
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs.
Definition: avcodec.h:1083
pixfmt.h
avcodec_flush_buffers
void avcodec_flush_buffers(AVCodecContext *avctx)
Reset the internal codec state / flush internal buffers.
Definition: avcodec.c:350
AVCodecParserContext::coded_height
int coded_height
Definition: avcodec.h:2840
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1379
AVCodecContext::opaque
void * opaque
Private data of the user, can be used to carry app specific stuff.
Definition: avcodec.h:487
pos
unsigned int pos
Definition: spdifenc.c:413
AVCodecParser::priv_data_size
int priv_data_size
Definition: avcodec.h:2855
dict.h
AVCodecContext::draw_horiz_band
void(* draw_horiz_band)(struct AVCodecContext *s, const AVFrame *src, int offset[AV_NUM_DATA_POINTERS], int y, int type, int height)
If non NULL, 'draw_horiz_band' is called by the libavcodec decoder to draw a horizontal band.
Definition: avcodec.h:758
AVCodecContext::max_qdiff
int max_qdiff
maximum quantizer difference between frames
Definition: avcodec.h:1270
AVCodecContext::dark_masking
float dark_masking
darkness masking (0-> disabled)
Definition: avcodec.h:862
AVCodecContext
main external API structure.
Definition: avcodec.h:445
AVCodecContext::active_thread_type
int active_thread_type
Which multithreading methods are in use by the codec.
Definition: avcodec.h:1601
c2
static const uint64_t c2
Definition: murmur3.c:53
AVCodecParserContext::field_order
enum AVFieldOrder field_order
Definition: avcodec.h:2810
AVCodecContext::execute
int(* execute)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size)
The codec may call this to execute several independent things.
Definition: avcodec.h:1612
channel_layout.h
AVCodecContext::qmin
int qmin
minimum quantizer
Definition: avcodec.h:1256
AVCodecContext::bidir_refine
int bidir_refine
Definition: avcodec.h:1017
AVCodecContext::profile
int profile
profile
Definition: avcodec.h:1639
defs.h
av_fast_padded_mallocz
void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_padded_malloc except that buffer will always be 0-initialized after call.
Definition: utils.c:65
AVCodecContext::get_encode_buffer
int(* get_encode_buffer)(struct AVCodecContext *s, AVPacket *pkt, int flags)
This callback is called at the beginning of each packet to get a data buffer for it.
Definition: avcodec.h:2019
AVCodecContext::spatial_cplx_masking
float spatial_cplx_masking
spatial complexity masking (0-> disabled)
Definition: avcodec.h:848
AVCodecContext::i_quant_offset
float i_quant_offset
qscale offset between P and I-frames
Definition: avcodec.h:827
AVCodecContext::discard_damaged_percentage
int discard_damaged_percentage
The percentage of damaged samples to discard a frame.
Definition: avcodec.h:1969
AVCodecContext::ticks_per_frame
attribute_deprecated int ticks_per_frame
For some codecs, the time base is closer to the field rate than the frame rate.
Definition: avcodec.h:576
AVCodecContext::mb_lmax
int mb_lmax
maximum MB Lagrange multiplier
Definition: avcodec.h:1011
AVCodecContext::export_side_data
int export_side_data
Bit set of AV_CODEC_EXPORT_DATA_* flags, which affects the kind of metadata exported in frame,...
Definition: avcodec.h:1926
AVCodecContext::pre_dia_size
int pre_dia_size
ME prepass diamond size & shape.
Definition: avcodec.h:939
AVCodecContext::debug
int debug
debug
Definition: avcodec.h:1396
AVCodecContext::coded_width
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:633
AVCodecContext::codec_type
enum AVMediaType codec_type
Definition: avcodec.h:453
AVCodecContext::seek_preroll
int seek_preroll
Number of samples to skip after a discontinuity.
Definition: avcodec.h:1140
av_parser_parse2
int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int64_t pts, int64_t dts, int64_t pos)
Parse a packet.
Definition: parser.c:115
avutil.h
AVCodecContext::max_b_frames
int max_b_frames
maximum number of B-frames between non-B-frames Note: The output will be delayed by max_b_frames+1 re...
Definition: avcodec.h:795
AVBufferRef
A reference to a data buffer.
Definition: buffer.h:82
AVCodecContext::rc_max_available_vbv_use
float rc_max_available_vbv_use
Ratecontrol attempt to use, at maximum, of what can be used without an underflow.
Definition: avcodec.h:1306
avcodec_parameters_from_context
int avcodec_parameters_from_context(struct AVCodecParameters *par, const AVCodecContext *codec)
Fill the parameters struct based on the values from the supplied codec context.
Definition: codec_par.c:137
AVCodecContext::codec_tag
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:470
codec_par.h
AV_PARSER_PTS_NB
#define AV_PARSER_PTS_NB
Definition: avcodec.h:2721
AVCodecContext::slices
int slices
Number of slices.
Definition: avcodec.h:1047
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
avcodec_default_get_encode_buffer
int avcodec_default_get_encode_buffer(AVCodecContext *s, AVPacket *pkt, int flags)
The default callback for AVCodecContext.get_encode_buffer().
Definition: encode.c:83
AVCodecParserContext::last_pos
int64_t last_pos
Previous frame byte position.
Definition: avcodec.h:2801
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
AVCodecContext::inter_matrix
uint16_t * inter_matrix
custom inter quantization matrix Must be allocated with the av_malloc() family of functions,...
Definition: avcodec.h:983
AVCodecParser
Definition: avcodec.h:2853
AVCodecContext::rc_override_count
int rc_override_count
ratecontrol override, see RcOverride
Definition: avcodec.h:1284
avcodec_configuration
const char * avcodec_configuration(void)
Return the libavcodec build-time configuration.
Definition: version.c:41
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:618
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
AVCodecParserContext::priv_data
void * priv_data
Definition: avcodec.h:2695
AVCodecContext::sw_pix_fmt
enum AVPixelFormat sw_pix_fmt
Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:664
AVCodecParserContext::cur_frame_dts
int64_t cur_frame_dts[AV_PARSER_PTS_NB]
Definition: avcodec.h:2725
AVCodecContext::codec_whitelist
char * codec_whitelist
',' separated list of allowed decoders.
Definition: avcodec.h:1907
AVDiscard
AVDiscard
Definition: defs.h:210
AVColorRange
AVColorRange
Visual content value range.
Definition: pixfmt.h:648
AVCodecParserContext::last_dts
int64_t last_dts
Definition: avcodec.h:2718
codec_desc.h
int
int
Definition: ffmpeg_filter.c:425
AVCodecContext::execute2
int(* execute2)(struct AVCodecContext *c, int(*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count)
The codec may call this to execute several independent things.
Definition: avcodec.h:1631
AVHWAccel::pix_fmt
enum AVPixelFormat pix_fmt
Supported pixel format.
Definition: avcodec.h:2102
AVCodecContext::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel.
Definition: avcodec.h:642
AVSubtitle::start_display_time
uint32_t start_display_time
Definition: avcodec.h:2216
AVCodecContext::compression_level
int compression_level
Definition: avcodec.h:1245
av_parser_close
void av_parser_close(AVCodecParserContext *s)
Definition: parser.c:193
AVHWAccel::id
enum AVCodecID id
Codec implemented by the hardware accelerator.
Definition: avcodec.h:2095