7385dd36a5654d9004070ffd16aea2b3fe6c6a78
[libav.git] / libavcodec / avcodec.h
1 /*
2 * copyright (c) 2001 Fabrice Bellard
3 *
4 * This file is part of Libav.
5 *
6 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23
24 /**
25 * @file
26 * @ingroup libavc
27 * Libavcodec external API header
28 */
29
30 #include <errno.h>
31 #include "libavutil/samplefmt.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avutil.h"
34 #include "libavutil/buffer.h"
35 #include "libavutil/cpu.h"
36 #include "libavutil/dict.h"
37 #include "libavutil/frame.h"
38 #include "libavutil/log.h"
39 #include "libavutil/pixfmt.h"
40 #include "libavutil/rational.h"
41
42 #include "version.h"
43
44 #if FF_API_FAST_MALLOC
45 // to provide fast_*alloc
46 #include "libavutil/mem.h"
47 #endif
48
49 /**
50 * @defgroup libavc Encoding/Decoding Library
51 * @{
52 *
53 * @defgroup lavc_decoding Decoding
54 * @{
55 * @}
56 *
57 * @defgroup lavc_encoding Encoding
58 * @{
59 * @}
60 *
61 * @defgroup lavc_codec Codecs
62 * @{
63 * @defgroup lavc_codec_native Native Codecs
64 * @{
65 * @}
66 * @defgroup lavc_codec_wrappers External library wrappers
67 * @{
68 * @}
69 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
70 * @{
71 * @}
72 * @}
73 * @defgroup lavc_internal Internal
74 * @{
75 * @}
76 * @}
77 *
78 */
79
80 /**
81 * @defgroup lavc_core Core functions/structures.
82 * @ingroup libavc
83 *
84 * Basic definitions, functions for querying libavcodec capabilities,
85 * allocating core structures, etc.
86 * @{
87 */
88
89
90 /**
91 * Identify the syntax and semantics of the bitstream.
92 * The principle is roughly:
93 * Two decoders with the same ID can decode the same streams.
94 * Two encoders with the same ID can encode compatible streams.
95 * There may be slight deviations from the principle due to implementation
96 * details.
97 *
98 * If you add a codec ID to this list, add it so that
99 * 1. no value of a existing codec ID changes (that would break ABI),
100 * 2. it is as close as possible to similar codecs.
101 *
102 * After adding new codec IDs, do not forget to add an entry to the codec
103 * descriptor list and bump libavcodec minor version.
104 */
105 enum AVCodecID {
106 AV_CODEC_ID_NONE,
107
108 /* video codecs */
109 AV_CODEC_ID_MPEG1VIDEO,
110 AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
111 #if FF_API_XVMC
112 AV_CODEC_ID_MPEG2VIDEO_XVMC,
113 #endif /* FF_API_XVMC */
114 AV_CODEC_ID_H261,
115 AV_CODEC_ID_H263,
116 AV_CODEC_ID_RV10,
117 AV_CODEC_ID_RV20,
118 AV_CODEC_ID_MJPEG,
119 AV_CODEC_ID_MJPEGB,
120 AV_CODEC_ID_LJPEG,
121 AV_CODEC_ID_SP5X,
122 AV_CODEC_ID_JPEGLS,
123 AV_CODEC_ID_MPEG4,
124 AV_CODEC_ID_RAWVIDEO,
125 AV_CODEC_ID_MSMPEG4V1,
126 AV_CODEC_ID_MSMPEG4V2,
127 AV_CODEC_ID_MSMPEG4V3,
128 AV_CODEC_ID_WMV1,
129 AV_CODEC_ID_WMV2,
130 AV_CODEC_ID_H263P,
131 AV_CODEC_ID_H263I,
132 AV_CODEC_ID_FLV1,
133 AV_CODEC_ID_SVQ1,
134 AV_CODEC_ID_SVQ3,
135 AV_CODEC_ID_DVVIDEO,
136 AV_CODEC_ID_HUFFYUV,
137 AV_CODEC_ID_CYUV,
138 AV_CODEC_ID_H264,
139 AV_CODEC_ID_INDEO3,
140 AV_CODEC_ID_VP3,
141 AV_CODEC_ID_THEORA,
142 AV_CODEC_ID_ASV1,
143 AV_CODEC_ID_ASV2,
144 AV_CODEC_ID_FFV1,
145 AV_CODEC_ID_4XM,
146 AV_CODEC_ID_VCR1,
147 AV_CODEC_ID_CLJR,
148 AV_CODEC_ID_MDEC,
149 AV_CODEC_ID_ROQ,
150 AV_CODEC_ID_INTERPLAY_VIDEO,
151 AV_CODEC_ID_XAN_WC3,
152 AV_CODEC_ID_XAN_WC4,
153 AV_CODEC_ID_RPZA,
154 AV_CODEC_ID_CINEPAK,
155 AV_CODEC_ID_WS_VQA,
156 AV_CODEC_ID_MSRLE,
157 AV_CODEC_ID_MSVIDEO1,
158 AV_CODEC_ID_IDCIN,
159 AV_CODEC_ID_8BPS,
160 AV_CODEC_ID_SMC,
161 AV_CODEC_ID_FLIC,
162 AV_CODEC_ID_TRUEMOTION1,
163 AV_CODEC_ID_VMDVIDEO,
164 AV_CODEC_ID_MSZH,
165 AV_CODEC_ID_ZLIB,
166 AV_CODEC_ID_QTRLE,
167 AV_CODEC_ID_TSCC,
168 AV_CODEC_ID_ULTI,
169 AV_CODEC_ID_QDRAW,
170 AV_CODEC_ID_VIXL,
171 AV_CODEC_ID_QPEG,
172 AV_CODEC_ID_PNG,
173 AV_CODEC_ID_PPM,
174 AV_CODEC_ID_PBM,
175 AV_CODEC_ID_PGM,
176 AV_CODEC_ID_PGMYUV,
177 AV_CODEC_ID_PAM,
178 AV_CODEC_ID_FFVHUFF,
179 AV_CODEC_ID_RV30,
180 AV_CODEC_ID_RV40,
181 AV_CODEC_ID_VC1,
182 AV_CODEC_ID_WMV3,
183 AV_CODEC_ID_LOCO,
184 AV_CODEC_ID_WNV1,
185 AV_CODEC_ID_AASC,
186 AV_CODEC_ID_INDEO2,
187 AV_CODEC_ID_FRAPS,
188 AV_CODEC_ID_TRUEMOTION2,
189 AV_CODEC_ID_BMP,
190 AV_CODEC_ID_CSCD,
191 AV_CODEC_ID_MMVIDEO,
192 AV_CODEC_ID_ZMBV,
193 AV_CODEC_ID_AVS,
194 AV_CODEC_ID_SMACKVIDEO,
195 AV_CODEC_ID_NUV,
196 AV_CODEC_ID_KMVC,
197 AV_CODEC_ID_FLASHSV,
198 AV_CODEC_ID_CAVS,
199 AV_CODEC_ID_JPEG2000,
200 AV_CODEC_ID_VMNC,
201 AV_CODEC_ID_VP5,
202 AV_CODEC_ID_VP6,
203 AV_CODEC_ID_VP6F,
204 AV_CODEC_ID_TARGA,
205 AV_CODEC_ID_DSICINVIDEO,
206 AV_CODEC_ID_TIERTEXSEQVIDEO,
207 AV_CODEC_ID_TIFF,
208 AV_CODEC_ID_GIF,
209 AV_CODEC_ID_DXA,
210 AV_CODEC_ID_DNXHD,
211 AV_CODEC_ID_THP,
212 AV_CODEC_ID_SGI,
213 AV_CODEC_ID_C93,
214 AV_CODEC_ID_BETHSOFTVID,
215 AV_CODEC_ID_PTX,
216 AV_CODEC_ID_TXD,
217 AV_CODEC_ID_VP6A,
218 AV_CODEC_ID_AMV,
219 AV_CODEC_ID_VB,
220 AV_CODEC_ID_PCX,
221 AV_CODEC_ID_SUNRAST,
222 AV_CODEC_ID_INDEO4,
223 AV_CODEC_ID_INDEO5,
224 AV_CODEC_ID_MIMIC,
225 AV_CODEC_ID_RL2,
226 AV_CODEC_ID_ESCAPE124,
227 AV_CODEC_ID_DIRAC,
228 AV_CODEC_ID_BFI,
229 AV_CODEC_ID_CMV,
230 AV_CODEC_ID_MOTIONPIXELS,
231 AV_CODEC_ID_TGV,
232 AV_CODEC_ID_TGQ,
233 AV_CODEC_ID_TQI,
234 AV_CODEC_ID_AURA,
235 AV_CODEC_ID_AURA2,
236 AV_CODEC_ID_V210X,
237 AV_CODEC_ID_TMV,
238 AV_CODEC_ID_V210,
239 AV_CODEC_ID_DPX,
240 AV_CODEC_ID_MAD,
241 AV_CODEC_ID_FRWU,
242 AV_CODEC_ID_FLASHSV2,
243 AV_CODEC_ID_CDGRAPHICS,
244 AV_CODEC_ID_R210,
245 AV_CODEC_ID_ANM,
246 AV_CODEC_ID_BINKVIDEO,
247 AV_CODEC_ID_IFF_ILBM,
248 AV_CODEC_ID_IFF_BYTERUN1,
249 AV_CODEC_ID_KGV1,
250 AV_CODEC_ID_YOP,
251 AV_CODEC_ID_VP8,
252 AV_CODEC_ID_PICTOR,
253 AV_CODEC_ID_ANSI,
254 AV_CODEC_ID_A64_MULTI,
255 AV_CODEC_ID_A64_MULTI5,
256 AV_CODEC_ID_R10K,
257 AV_CODEC_ID_MXPEG,
258 AV_CODEC_ID_LAGARITH,
259 AV_CODEC_ID_PRORES,
260 AV_CODEC_ID_JV,
261 AV_CODEC_ID_DFA,
262 AV_CODEC_ID_WMV3IMAGE,
263 AV_CODEC_ID_VC1IMAGE,
264 AV_CODEC_ID_UTVIDEO,
265 AV_CODEC_ID_BMV_VIDEO,
266 AV_CODEC_ID_VBLE,
267 AV_CODEC_ID_DXTORY,
268 AV_CODEC_ID_V410,
269 AV_CODEC_ID_XWD,
270 AV_CODEC_ID_CDXL,
271 AV_CODEC_ID_XBM,
272 AV_CODEC_ID_ZEROCODEC,
273 AV_CODEC_ID_MSS1,
274 AV_CODEC_ID_MSA1,
275 AV_CODEC_ID_TSCC2,
276 AV_CODEC_ID_MTS2,
277 AV_CODEC_ID_CLLC,
278 AV_CODEC_ID_MSS2,
279 AV_CODEC_ID_VP9,
280 AV_CODEC_ID_AIC,
281 AV_CODEC_ID_ESCAPE130,
282 AV_CODEC_ID_G2M,
283 AV_CODEC_ID_WEBP,
284 AV_CODEC_ID_HNM4_VIDEO,
285 AV_CODEC_ID_HEVC,
286 AV_CODEC_ID_FIC,
287 AV_CODEC_ID_ALIAS_PIX,
288 AV_CODEC_ID_BRENDER_PIX,
289 AV_CODEC_ID_PAF_VIDEO,
290 AV_CODEC_ID_EXR,
291 AV_CODEC_ID_VP7,
292 AV_CODEC_ID_SANM,
293 AV_CODEC_ID_SGIRLE,
294 AV_CODEC_ID_MVC1,
295 AV_CODEC_ID_MVC2,
296
297 /* various PCM "codecs" */
298 AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
299 AV_CODEC_ID_PCM_S16LE = 0x10000,
300 AV_CODEC_ID_PCM_S16BE,
301 AV_CODEC_ID_PCM_U16LE,
302 AV_CODEC_ID_PCM_U16BE,
303 AV_CODEC_ID_PCM_S8,
304 AV_CODEC_ID_PCM_U8,
305 AV_CODEC_ID_PCM_MULAW,
306 AV_CODEC_ID_PCM_ALAW,
307 AV_CODEC_ID_PCM_S32LE,
308 AV_CODEC_ID_PCM_S32BE,
309 AV_CODEC_ID_PCM_U32LE,
310 AV_CODEC_ID_PCM_U32BE,
311 AV_CODEC_ID_PCM_S24LE,
312 AV_CODEC_ID_PCM_S24BE,
313 AV_CODEC_ID_PCM_U24LE,
314 AV_CODEC_ID_PCM_U24BE,
315 AV_CODEC_ID_PCM_S24DAUD,
316 AV_CODEC_ID_PCM_ZORK,
317 AV_CODEC_ID_PCM_S16LE_PLANAR,
318 AV_CODEC_ID_PCM_DVD,
319 AV_CODEC_ID_PCM_F32BE,
320 AV_CODEC_ID_PCM_F32LE,
321 AV_CODEC_ID_PCM_F64BE,
322 AV_CODEC_ID_PCM_F64LE,
323 AV_CODEC_ID_PCM_BLURAY,
324 AV_CODEC_ID_PCM_LXF,
325 AV_CODEC_ID_S302M,
326 AV_CODEC_ID_PCM_S8_PLANAR,
327 AV_CODEC_ID_PCM_S24LE_PLANAR,
328 AV_CODEC_ID_PCM_S32LE_PLANAR,
329
330 /* various ADPCM codecs */
331 AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
332 AV_CODEC_ID_ADPCM_IMA_WAV,
333 AV_CODEC_ID_ADPCM_IMA_DK3,
334 AV_CODEC_ID_ADPCM_IMA_DK4,
335 AV_CODEC_ID_ADPCM_IMA_WS,
336 AV_CODEC_ID_ADPCM_IMA_SMJPEG,
337 AV_CODEC_ID_ADPCM_MS,
338 AV_CODEC_ID_ADPCM_4XM,
339 AV_CODEC_ID_ADPCM_XA,
340 AV_CODEC_ID_ADPCM_ADX,
341 AV_CODEC_ID_ADPCM_EA,
342 AV_CODEC_ID_ADPCM_G726,
343 AV_CODEC_ID_ADPCM_CT,
344 AV_CODEC_ID_ADPCM_SWF,
345 AV_CODEC_ID_ADPCM_YAMAHA,
346 AV_CODEC_ID_ADPCM_SBPRO_4,
347 AV_CODEC_ID_ADPCM_SBPRO_3,
348 AV_CODEC_ID_ADPCM_SBPRO_2,
349 AV_CODEC_ID_ADPCM_THP,
350 AV_CODEC_ID_ADPCM_IMA_AMV,
351 AV_CODEC_ID_ADPCM_EA_R1,
352 AV_CODEC_ID_ADPCM_EA_R3,
353 AV_CODEC_ID_ADPCM_EA_R2,
354 AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
355 AV_CODEC_ID_ADPCM_IMA_EA_EACS,
356 AV_CODEC_ID_ADPCM_EA_XAS,
357 AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
358 AV_CODEC_ID_ADPCM_IMA_ISS,
359 AV_CODEC_ID_ADPCM_G722,
360 AV_CODEC_ID_ADPCM_IMA_APC,
361 AV_CODEC_ID_ADPCM_VIMA,
362
363 /* AMR */
364 AV_CODEC_ID_AMR_NB = 0x12000,
365 AV_CODEC_ID_AMR_WB,
366
367 /* RealAudio codecs*/
368 AV_CODEC_ID_RA_144 = 0x13000,
369 AV_CODEC_ID_RA_288,
370
371 /* various DPCM codecs */
372 AV_CODEC_ID_ROQ_DPCM = 0x14000,
373 AV_CODEC_ID_INTERPLAY_DPCM,
374 AV_CODEC_ID_XAN_DPCM,
375 AV_CODEC_ID_SOL_DPCM,
376
377 /* audio codecs */
378 AV_CODEC_ID_MP2 = 0x15000,
379 AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
380 AV_CODEC_ID_AAC,
381 AV_CODEC_ID_AC3,
382 AV_CODEC_ID_DTS,
383 AV_CODEC_ID_VORBIS,
384 AV_CODEC_ID_DVAUDIO,
385 AV_CODEC_ID_WMAV1,
386 AV_CODEC_ID_WMAV2,
387 AV_CODEC_ID_MACE3,
388 AV_CODEC_ID_MACE6,
389 AV_CODEC_ID_VMDAUDIO,
390 AV_CODEC_ID_FLAC,
391 AV_CODEC_ID_MP3ADU,
392 AV_CODEC_ID_MP3ON4,
393 AV_CODEC_ID_SHORTEN,
394 AV_CODEC_ID_ALAC,
395 AV_CODEC_ID_WESTWOOD_SND1,
396 AV_CODEC_ID_GSM, ///< as in Berlin toast format
397 AV_CODEC_ID_QDM2,
398 AV_CODEC_ID_COOK,
399 AV_CODEC_ID_TRUESPEECH,
400 AV_CODEC_ID_TTA,
401 AV_CODEC_ID_SMACKAUDIO,
402 AV_CODEC_ID_QCELP,
403 AV_CODEC_ID_WAVPACK,
404 AV_CODEC_ID_DSICINAUDIO,
405 AV_CODEC_ID_IMC,
406 AV_CODEC_ID_MUSEPACK7,
407 AV_CODEC_ID_MLP,
408 AV_CODEC_ID_GSM_MS, /* as found in WAV */
409 AV_CODEC_ID_ATRAC3,
410 #if FF_API_VOXWARE
411 AV_CODEC_ID_VOXWARE,
412 #endif
413 AV_CODEC_ID_APE,
414 AV_CODEC_ID_NELLYMOSER,
415 AV_CODEC_ID_MUSEPACK8,
416 AV_CODEC_ID_SPEEX,
417 AV_CODEC_ID_WMAVOICE,
418 AV_CODEC_ID_WMAPRO,
419 AV_CODEC_ID_WMALOSSLESS,
420 AV_CODEC_ID_ATRAC3P,
421 AV_CODEC_ID_EAC3,
422 AV_CODEC_ID_SIPR,
423 AV_CODEC_ID_MP1,
424 AV_CODEC_ID_TWINVQ,
425 AV_CODEC_ID_TRUEHD,
426 AV_CODEC_ID_MP4ALS,
427 AV_CODEC_ID_ATRAC1,
428 AV_CODEC_ID_BINKAUDIO_RDFT,
429 AV_CODEC_ID_BINKAUDIO_DCT,
430 AV_CODEC_ID_AAC_LATM,
431 AV_CODEC_ID_QDMC,
432 AV_CODEC_ID_CELT,
433 AV_CODEC_ID_G723_1,
434 AV_CODEC_ID_G729,
435 AV_CODEC_ID_8SVX_EXP,
436 AV_CODEC_ID_8SVX_FIB,
437 AV_CODEC_ID_BMV_AUDIO,
438 AV_CODEC_ID_RALF,
439 AV_CODEC_ID_IAC,
440 AV_CODEC_ID_ILBC,
441 AV_CODEC_ID_OPUS,
442 AV_CODEC_ID_COMFORT_NOISE,
443 AV_CODEC_ID_TAK,
444 AV_CODEC_ID_METASOUND,
445 AV_CODEC_ID_PAF_AUDIO,
446 AV_CODEC_ID_ON2AVC,
447
448 /* subtitle codecs */
449 AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
450 AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
451 AV_CODEC_ID_DVB_SUBTITLE,
452 AV_CODEC_ID_TEXT, ///< raw UTF-8 text
453 AV_CODEC_ID_XSUB,
454 AV_CODEC_ID_SSA,
455 AV_CODEC_ID_MOV_TEXT,
456 AV_CODEC_ID_HDMV_PGS_SUBTITLE,
457 AV_CODEC_ID_DVB_TELETEXT,
458 AV_CODEC_ID_SRT,
459
460 /* other specific kind of codecs (generally used for attachments) */
461 AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
462 AV_CODEC_ID_TTF = 0x18000,
463
464 AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
465
466 AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
467 * stream (only used by libavformat) */
468 AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
469 * stream (only used by libavformat) */
470 AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
471 };
472
473 /**
474 * This struct describes the properties of a single codec described by an
475 * AVCodecID.
476 * @see avcodec_get_descriptor()
477 */
478 typedef struct AVCodecDescriptor {
479 enum AVCodecID id;
480 enum AVMediaType type;
481 /**
482 * Name of the codec described by this descriptor. It is non-empty and
483 * unique for each codec descriptor. It should contain alphanumeric
484 * characters and '_' only.
485 */
486 const char *name;
487 /**
488 * A more descriptive name for this codec. May be NULL.
489 */
490 const char *long_name;
491 /**
492 * Codec properties, a combination of AV_CODEC_PROP_* flags.
493 */
494 int props;
495 } AVCodecDescriptor;
496
497 /**
498 * Codec uses only intra compression.
499 * Video codecs only.
500 */
501 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
502 /**
503 * Codec supports lossy compression. Audio and video codecs only.
504 * @note a codec may support both lossy and lossless
505 * compression modes
506 */
507 #define AV_CODEC_PROP_LOSSY (1 << 1)
508 /**
509 * Codec supports lossless compression. Audio and video codecs only.
510 */
511 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
512 /**
513 * Codec supports frame reordering. That is, the coded order (the order in which
514 * the encoded packets are output by the encoders / stored / input to the
515 * decoders) may be different from the presentation order of the corresponding
516 * frames.
517 *
518 * For codecs that do not have this property set, PTS and DTS should always be
519 * equal.
520 */
521 #define AV_CODEC_PROP_REORDER (1 << 3)
522
523 /**
524 * @ingroup lavc_decoding
525 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
526 * This is mainly needed because some optimized bitstream readers read
527 * 32 or 64 bit at once and could read over the end.<br>
528 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
529 * MPEG bitstreams could cause overread and segfault.
530 */
531 #define FF_INPUT_BUFFER_PADDING_SIZE 8
532
533 /**
534 * @ingroup lavc_encoding
535 * minimum encoding buffer size
536 * Used to avoid some checks during header writing.
537 */
538 #define FF_MIN_BUFFER_SIZE 16384
539
540
541 /**
542 * @ingroup lavc_encoding
543 * motion estimation type.
544 */
545 enum Motion_Est_ID {
546 ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
547 ME_FULL,
548 ME_LOG,
549 ME_PHODS,
550 ME_EPZS, ///< enhanced predictive zonal search
551 ME_X1, ///< reserved for experiments
552 ME_HEX, ///< hexagon based search
553 ME_UMH, ///< uneven multi-hexagon search
554 ME_TESA, ///< transformed exhaustive search algorithm
555 };
556
557 /**
558 * @ingroup lavc_decoding
559 */
560 enum AVDiscard{
561 /* We leave some space between them for extensions (drop some
562 * keyframes for intra-only or drop just some bidir frames). */
563 AVDISCARD_NONE =-16, ///< discard nothing
564 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
565 AVDISCARD_NONREF = 8, ///< discard all non reference
566 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
567 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
568 AVDISCARD_ALL = 48, ///< discard all
569 };
570
571 enum AVAudioServiceType {
572 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
573 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
574 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
575 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
576 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
577 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
578 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
579 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
580 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
581 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
582 };
583
584 /**
585 * @ingroup lavc_encoding
586 */
587 typedef struct RcOverride{
588 int start_frame;
589 int end_frame;
590 int qscale; // If this is 0 then quality_factor will be used instead.
591 float quality_factor;
592 } RcOverride;
593
594 #if FF_API_MAX_BFRAMES
595 /**
596 * @deprecated there is no libavcodec-wide limit on the number of B-frames
597 */
598 #define FF_MAX_B_FRAMES 16
599 #endif
600
601 /* encoding support
602 These flags can be passed in AVCodecContext.flags before initialization.
603 Note: Not everything is supported yet.
604 */
605
606 /**
607 * Allow decoders to produce frames with data planes that are not aligned
608 * to CPU requirements (e.g. due to cropping).
609 */
610 #define CODEC_FLAG_UNALIGNED 0x0001
611 #define CODEC_FLAG_QSCALE 0x0002 ///< Use fixed qscale.
612 #define CODEC_FLAG_4MV 0x0004 ///< 4 MV per MB allowed / advanced prediction for H.263.
613 #define CODEC_FLAG_OUTPUT_CORRUPT 0x0008 ///< Output even those frames that might be corrupted
614 #define CODEC_FLAG_QPEL 0x0010 ///< Use qpel MC.
615 #if FF_API_GMC
616 /**
617 * @deprecated use the "gmc" private option of the libxvid encoder
618 */
619 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
620 #endif
621 #if FF_API_MV0
622 /**
623 * @deprecated use the flag "mv0" in the "mpv_flags" private option of the
624 * mpegvideo encoders
625 */
626 #define CODEC_FLAG_MV0 0x0040
627 #endif
628 #if FF_API_INPUT_PRESERVED
629 /**
630 * @deprecated passing reference-counted frames to the encoders replaces this
631 * flag
632 */
633 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
634 #endif
635 #define CODEC_FLAG_PASS1 0x0200 ///< Use internal 2pass ratecontrol in first pass mode.
636 #define CODEC_FLAG_PASS2 0x0400 ///< Use internal 2pass ratecontrol in second pass mode.
637 #define CODEC_FLAG_GRAY 0x2000 ///< Only decode/encode grayscale.
638 #if FF_API_EMU_EDGE
639 /**
640 * @deprecated edges are not used/required anymore. I.e. this flag is now always
641 * set.
642 */
643 #define CODEC_FLAG_EMU_EDGE 0x4000
644 #endif
645 #define CODEC_FLAG_PSNR 0x8000 ///< error[?] variables will be set during encoding.
646 #define CODEC_FLAG_TRUNCATED 0x00010000 /** Input bitstream might be truncated at a random
647 location instead of only at frame boundaries. */
648 #if FF_API_NORMALIZE_AQP
649 /**
650 * @deprecated use the flag "naq" in the "mpv_flags" private option of the
651 * mpegvideo encoders
652 */
653 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000
654 #endif
655 #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
656 #define CODEC_FLAG_LOW_DELAY 0x00080000 ///< Force low delay.
657 #define CODEC_FLAG_GLOBAL_HEADER 0x00400000 ///< Place global headers in extradata instead of every keyframe.
658 #define CODEC_FLAG_BITEXACT 0x00800000 ///< Use only bitexact stuff (except (I)DCT).
659 /* Fx : Flag for h263+ extra options */
660 #define CODEC_FLAG_AC_PRED 0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
661 #define CODEC_FLAG_LOOP_FILTER 0x00000800 ///< loop filter
662 #define CODEC_FLAG_INTERLACED_ME 0x20000000 ///< interlaced motion estimation
663 #define CODEC_FLAG_CLOSED_GOP 0x80000000
664 #define CODEC_FLAG2_FAST 0x00000001 ///< Allow non spec compliant speedup tricks.
665 #define CODEC_FLAG2_NO_OUTPUT 0x00000004 ///< Skip bitstream encoding.
666 #define CODEC_FLAG2_LOCAL_HEADER 0x00000008 ///< Place global headers at every keyframe instead of in extradata.
667 #define CODEC_FLAG2_IGNORE_CROP 0x00010000 ///< Discard cropping information from SPS.
668
669 #define CODEC_FLAG2_CHUNKS 0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
670
671 /* Unsupported options :
672 * Syntax Arithmetic coding (SAC)
673 * Reference Picture Selection
674 * Independent Segment Decoding */
675 /* /Fx */
676 /* codec capabilities */
677
678 #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
679 /**
680 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
681 * If not set, it might not use get_buffer() at all or use operations that
682 * assume the buffer was allocated by avcodec_default_get_buffer.
683 */
684 #define CODEC_CAP_DR1 0x0002
685 #define CODEC_CAP_TRUNCATED 0x0008
686 #if FF_API_XVMC
687 /* Codec can export data for HW decoding (XvMC). */
688 #define CODEC_CAP_HWACCEL 0x0010
689 #endif /* FF_API_XVMC */
690 /**
691 * Encoder or decoder requires flushing with NULL input at the end in order to
692 * give the complete and correct output.
693 *
694 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
695 * with NULL data. The user can still send NULL data to the public encode
696 * or decode function, but libavcodec will not pass it along to the codec
697 * unless this flag is set.
698 *
699 * Decoders:
700 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
701 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
702 * returns frames.
703 *
704 * Encoders:
705 * The encoder needs to be fed with NULL data at the end of encoding until the
706 * encoder no longer returns data.
707 *
708 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
709 * flag also means that the encoder must set the pts and duration for
710 * each output packet. If this flag is not set, the pts and duration will
711 * be determined by libavcodec from the input frame.
712 */
713 #define CODEC_CAP_DELAY 0x0020
714 /**
715 * Codec can be fed a final frame with a smaller size.
716 * This can be used to prevent truncation of the last audio samples.
717 */
718 #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
719 #if FF_API_CAP_VDPAU
720 /**
721 * Codec can export data for HW decoding (VDPAU).
722 */
723 #define CODEC_CAP_HWACCEL_VDPAU 0x0080
724 #endif
725 /**
726 * Codec can output multiple frames per AVPacket
727 * Normally demuxers return one frame at a time, demuxers which do not do
728 * are connected to a parser to split what they return into proper frames.
729 * This flag is reserved to the very rare category of codecs which have a
730 * bitstream that cannot be split into frames without timeconsuming
731 * operations like full decoding. Demuxers carring such bitstreams thus
732 * may return multiple frames in a packet. This has many disadvantages like
733 * prohibiting stream copy in many cases thus it should only be considered
734 * as a last resort.
735 */
736 #define CODEC_CAP_SUBFRAMES 0x0100
737 /**
738 * Codec is experimental and is thus avoided in favor of non experimental
739 * encoders
740 */
741 #define CODEC_CAP_EXPERIMENTAL 0x0200
742 /**
743 * Codec should fill in channel configuration and samplerate instead of container
744 */
745 #define CODEC_CAP_CHANNEL_CONF 0x0400
746 #if FF_API_NEG_LINESIZES
747 /**
748 * @deprecated no codecs use this capability
749 */
750 #define CODEC_CAP_NEG_LINESIZES 0x0800
751 #endif
752 /**
753 * Codec supports frame-level multithreading.
754 */
755 #define CODEC_CAP_FRAME_THREADS 0x1000
756 /**
757 * Codec supports slice-based (or partition-based) multithreading.
758 */
759 #define CODEC_CAP_SLICE_THREADS 0x2000
760 /**
761 * Codec supports changed parameters at any point.
762 */
763 #define CODEC_CAP_PARAM_CHANGE 0x4000
764 /**
765 * Codec supports avctx->thread_count == 0 (auto).
766 */
767 #define CODEC_CAP_AUTO_THREADS 0x8000
768 /**
769 * Audio encoder supports receiving a different number of samples in each call.
770 */
771 #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
772
773 #if FF_API_MB_TYPE
774 //The following defines may change, don't expect compatibility if you use them.
775 #define MB_TYPE_INTRA4x4 0x0001
776 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
777 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
778 #define MB_TYPE_16x16 0x0008
779 #define MB_TYPE_16x8 0x0010
780 #define MB_TYPE_8x16 0x0020
781 #define MB_TYPE_8x8 0x0040
782 #define MB_TYPE_INTERLACED 0x0080
783 #define MB_TYPE_DIRECT2 0x0100 //FIXME
784 #define MB_TYPE_ACPRED 0x0200
785 #define MB_TYPE_GMC 0x0400
786 #define MB_TYPE_SKIP 0x0800
787 #define MB_TYPE_P0L0 0x1000
788 #define MB_TYPE_P1L0 0x2000
789 #define MB_TYPE_P0L1 0x4000
790 #define MB_TYPE_P1L1 0x8000
791 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
792 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
793 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
794 #define MB_TYPE_QUANT 0x00010000
795 #define MB_TYPE_CBP 0x00020000
796 //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
797 #endif
798
799 /**
800 * Pan Scan area.
801 * This specifies the area which should be displayed.
802 * Note there may be multiple such areas for one frame.
803 */
804 typedef struct AVPanScan{
805 /**
806 * id
807 * - encoding: Set by user.
808 * - decoding: Set by libavcodec.
809 */
810 int id;
811
812 /**
813 * width and height in 1/16 pel
814 * - encoding: Set by user.
815 * - decoding: Set by libavcodec.
816 */
817 int width;
818 int height;
819
820 /**
821 * position of the top left corner in 1/16 pel for up to 3 fields/frames
822 * - encoding: Set by user.
823 * - decoding: Set by libavcodec.
824 */
825 int16_t position[3][2];
826 }AVPanScan;
827
828 #if FF_API_QSCALE_TYPE
829 #define FF_QSCALE_TYPE_MPEG1 0
830 #define FF_QSCALE_TYPE_MPEG2 1
831 #define FF_QSCALE_TYPE_H264 2
832 #define FF_QSCALE_TYPE_VP56 3
833 #endif
834
835 #if FF_API_GET_BUFFER
836 #define FF_BUFFER_TYPE_INTERNAL 1
837 #define FF_BUFFER_TYPE_USER 2 ///< direct rendering buffers (image is (de)allocated by user)
838 #define FF_BUFFER_TYPE_SHARED 4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
839 #define FF_BUFFER_TYPE_COPY 8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
840
841 #define FF_BUFFER_HINTS_VALID 0x01 // Buffer hints value is meaningful (if 0 ignore).
842 #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
843 #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
844 #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
845 #endif
846
847 /**
848 * The decoder will keep a reference to the frame and may reuse it later.
849 */
850 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
851
852 /**
853 * @defgroup lavc_packet AVPacket
854 *
855 * Types and functions for working with AVPacket.
856 * @{
857 */
858 enum AVPacketSideDataType {
859 AV_PKT_DATA_PALETTE,
860 AV_PKT_DATA_NEW_EXTRADATA,
861
862 /**
863 * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
864 * @code
865 * u32le param_flags
866 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
867 * s32le channel_count
868 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
869 * u64le channel_layout
870 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
871 * s32le sample_rate
872 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
873 * s32le width
874 * s32le height
875 * @endcode
876 */
877 AV_PKT_DATA_PARAM_CHANGE,
878
879 /**
880 * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
881 * structures with info about macroblocks relevant to splitting the
882 * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
883 * That is, it does not necessarily contain info about all macroblocks,
884 * as long as the distance between macroblocks in the info is smaller
885 * than the target payload size.
886 * Each MB info structure is 12 bytes, and is laid out as follows:
887 * @code
888 * u32le bit offset from the start of the packet
889 * u8 current quantizer at the start of the macroblock
890 * u8 GOB number
891 * u16le macroblock address within the GOB
892 * u8 horizontal MV predictor
893 * u8 vertical MV predictor
894 * u8 horizontal MV predictor for block number 3
895 * u8 vertical MV predictor for block number 3
896 * @endcode
897 */
898 AV_PKT_DATA_H263_MB_INFO,
899
900 /**
901 * This side data should be associated with an audio stream and contains
902 * ReplayGain information in form of the AVReplayGain struct.
903 */
904 AV_PKT_DATA_REPLAYGAIN,
905
906 /**
907 * This side data contains a 3x3 transformation matrix describing an affine
908 * transformation that needs to be applied to the decoded video frames for
909 * correct presentation.
910 *
911 * See libavutil/display.h for a detailed description of the data.
912 */
913 AV_PKT_DATA_DISPLAYMATRIX,
914 };
915
916 typedef struct AVPacketSideData {
917 uint8_t *data;
918 int size;
919 enum AVPacketSideDataType type;
920 } AVPacketSideData;
921
922 /**
923 * This structure stores compressed data. It is typically exported by demuxers
924 * and then passed as input to decoders, or received as output from encoders and
925 * then passed to muxers.
926 *
927 * For video, it should typically contain one compressed frame. For audio it may
928 * contain several compressed frames.
929 *
930 * AVPacket is one of the few structs in Libav, whose size is a part of public
931 * ABI. Thus it may be allocated on stack and no new fields can be added to it
932 * without libavcodec and libavformat major bump.
933 *
934 * The semantics of data ownership depends on the buf or destruct (deprecated)
935 * fields. If either is set, the packet data is dynamically allocated and is
936 * valid indefinitely until av_free_packet() is called (which in turn calls
937 * av_buffer_unref()/the destruct callback to free the data). If neither is set,
938 * the packet data is typically backed by some static buffer somewhere and is
939 * only valid for a limited time (e.g. until the next read call when demuxing).
940 *
941 * The side data is always allocated with av_malloc() and is freed in
942 * av_free_packet().
943 */
944 typedef struct AVPacket {
945 /**
946 * A reference to the reference-counted buffer where the packet data is
947 * stored.
948 * May be NULL, then the packet data is not reference-counted.
949 */
950 AVBufferRef *buf;
951 /**
952 * Presentation timestamp in AVStream->time_base units; the time at which
953 * the decompressed packet will be presented to the user.
954 * Can be AV_NOPTS_VALUE if it is not stored in the file.
955 * pts MUST be larger or equal to dts as presentation cannot happen before
956 * decompression, unless one wants to view hex dumps. Some formats misuse
957 * the terms dts and pts/cts to mean something different. Such timestamps
958 * must be converted to true pts/dts before they are stored in AVPacket.
959 */
960 int64_t pts;
961 /**
962 * Decompression timestamp in AVStream->time_base units; the time at which
963 * the packet is decompressed.
964 * Can be AV_NOPTS_VALUE if it is not stored in the file.
965 */
966 int64_t dts;
967 uint8_t *data;
968 int size;
969 int stream_index;
970 /**
971 * A combination of AV_PKT_FLAG values
972 */
973 int flags;
974 /**
975 * Additional packet data that can be provided by the container.
976 * Packet can contain several types of side information.
977 */
978 AVPacketSideData *side_data;
979 int side_data_elems;
980
981 /**
982 * Duration of this packet in AVStream->time_base units, 0 if unknown.
983 * Equals next_pts - this_pts in presentation order.
984 */
985 int duration;
986 #if FF_API_DESTRUCT_PACKET
987 attribute_deprecated
988 void (*destruct)(struct AVPacket *);
989 attribute_deprecated
990 void *priv;
991 #endif
992 int64_t pos; ///< byte position in stream, -1 if unknown
993
994 /**
995 * Time difference in AVStream->time_base units from the pts of this
996 * packet to the point at which the output from the decoder has converged
997 * independent from the availability of previous frames. That is, the
998 * frames are virtually identical no matter if decoding started from
999 * the very first frame or from this keyframe.
1000 * Is AV_NOPTS_VALUE if unknown.
1001 * This field is not the display duration of the current packet.
1002 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
1003 * set.
1004 *
1005 * The purpose of this field is to allow seeking in streams that have no
1006 * keyframes in the conventional sense. It corresponds to the
1007 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
1008 * essential for some types of subtitle streams to ensure that all
1009 * subtitles are correctly displayed after seeking.
1010 */
1011 int64_t convergence_duration;
1012 } AVPacket;
1013 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1014 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1015
1016 enum AVSideDataParamChangeFlags {
1017 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1018 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1019 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1020 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1021 };
1022 /**
1023 * @}
1024 */
1025
1026 struct AVCodecInternal;
1027
1028 enum AVFieldOrder {
1029 AV_FIELD_UNKNOWN,
1030 AV_FIELD_PROGRESSIVE,
1031 AV_FIELD_TT, //< Top coded_first, top displayed first
1032 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1033 AV_FIELD_TB, //< Top coded first, bottom displayed first
1034 AV_FIELD_BT, //< Bottom coded first, top displayed first
1035 };
1036
1037 /**
1038 * main external API structure.
1039 * New fields can be added to the end with minor version bumps.
1040 * Removal, reordering and changes to existing fields require a major
1041 * version bump.
1042 * sizeof(AVCodecContext) must not be used outside libav*.
1043 */
1044 typedef struct AVCodecContext {
1045 /**
1046 * information on struct for av_log
1047 * - set by avcodec_alloc_context3
1048 */
1049 const AVClass *av_class;
1050 int log_level_offset;
1051
1052 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1053 const struct AVCodec *codec;
1054 #if FF_API_CODEC_NAME
1055 /**
1056 * @deprecated this field is not used for anything in libavcodec
1057 */
1058 attribute_deprecated
1059 char codec_name[32];
1060 #endif
1061 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1062
1063 /**
1064 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1065 * This is used to work around some encoder bugs.
1066 * A demuxer should set this to what is stored in the field used to identify the codec.
1067 * If there are multiple such fields in a container then the demuxer should choose the one
1068 * which maximizes the information about the used codec.
1069 * If the codec tag field in a container is larger than 32 bits then the demuxer should
1070 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1071 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1072 * first.
1073 * - encoding: Set by user, if not then the default based on codec_id will be used.
1074 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1075 */
1076 unsigned int codec_tag;
1077
1078 /**
1079 * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1080 * This is used to work around some encoder bugs.
1081 * - encoding: unused
1082 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1083 */
1084 unsigned int stream_codec_tag;
1085
1086 void *priv_data;
1087
1088 /**
1089 * Private context used for internal data.
1090 *
1091 * Unlike priv_data, this is not codec-specific. It is used in general
1092 * libavcodec functions.
1093 */
1094 struct AVCodecInternal *internal;
1095
1096 /**
1097 * Private data of the user, can be used to carry app specific stuff.
1098 * - encoding: Set by user.
1099 * - decoding: Set by user.
1100 */
1101 void *opaque;
1102
1103 /**
1104 * the average bitrate
1105 * - encoding: Set by user; unused for constant quantizer encoding.
1106 * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
1107 */
1108 int bit_rate;
1109
1110 /**
1111 * number of bits the bitstream is allowed to diverge from the reference.
1112 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1113 * - encoding: Set by user; unused for constant quantizer encoding.
1114 * - decoding: unused
1115 */
1116 int bit_rate_tolerance;
1117
1118 /**
1119 * Global quality for codecs which cannot change it per frame.
1120 * This should be proportional to MPEG-1/2/4 qscale.
1121 * - encoding: Set by user.
1122 * - decoding: unused
1123 */
1124 int global_quality;
1125
1126 /**
1127 * - encoding: Set by user.
1128 * - decoding: unused
1129 */
1130 int compression_level;
1131 #define FF_COMPRESSION_DEFAULT -1
1132
1133 /**
1134 * CODEC_FLAG_*.
1135 * - encoding: Set by user.
1136 * - decoding: Set by user.
1137 */
1138 int flags;
1139
1140 /**
1141 * CODEC_FLAG2_*
1142 * - encoding: Set by user.
1143 * - decoding: Set by user.
1144 */
1145 int flags2;
1146
1147 /**
1148 * some codecs need / can use extradata like Huffman tables.
1149 * mjpeg: Huffman tables
1150 * rv10: additional flags
1151 * mpeg4: global headers (they can be in the bitstream or here)
1152 * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
1153 * than extradata_size to avoid prolems if it is read with the bitstream reader.
1154 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1155 * - encoding: Set/allocated/freed by libavcodec.
1156 * - decoding: Set/allocated/freed by user.
1157 */
1158 uint8_t *extradata;
1159 int extradata_size;
1160
1161 /**
1162 * This is the fundamental unit of time (in seconds) in terms
1163 * of which frame timestamps are represented. For fixed-fps content,
1164 * timebase should be 1/framerate and timestamp increments should be
1165 * identically 1.
1166 * - encoding: MUST be set by user.
1167 * - decoding: Set by libavcodec.
1168 */
1169 AVRational time_base;
1170
1171 /**
1172 * For some codecs, the time base is closer to the field rate than the frame rate.
1173 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1174 * if no telecine is used ...
1175 *
1176 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1177 */
1178 int ticks_per_frame;
1179
1180 /**
1181 * Codec delay.
1182 *
1183 * Video:
1184 * Number of frames the decoded output will be delayed relative to the
1185 * encoded input.
1186 *
1187 * Audio:
1188 * For encoding, this is the number of "priming" samples added by the
1189 * encoder to the beginning of the stream. The decoded output will be
1190 * delayed by this many samples relative to the input to the encoder (or
1191 * more, if the decoder adds its own padding).
1192 * The timestamps on the output packets are adjusted by the encoder so
1193 * that they always refer to the first sample of the data actually
1194 * contained in the packet, including any added padding.
1195 * E.g. if the timebase is 1/samplerate and the timestamp of the first
1196 * input sample is 0, the timestamp of the first output packet will be
1197 * -delay.
1198 *
1199 * For decoding, this is the number of samples the decoder needs to
1200 * output before the decoder's output is valid. When seeking, you should
1201 * start decoding this many samples prior to your desired seek point.
1202 *
1203 * - encoding: Set by libavcodec.
1204 * - decoding: Set by libavcodec.
1205 */
1206 int delay;
1207
1208
1209 /* video only */
1210 /**
1211 * picture width / height.
1212 * - encoding: MUST be set by user.
1213 * - decoding: May be set by the user before opening the decoder if known e.g.
1214 * from the container. Some decoders will require the dimensions
1215 * to be set by the caller. During decoding, the decoder may
1216 * overwrite those values as required.
1217 */
1218 int width, height;
1219
1220 /**
1221 * Bitstream width / height, may be different from width/height e.g. when
1222 * the decoded frame is cropped before being output.
1223 * - encoding: unused
1224 * - decoding: May be set by the user before opening the decoder if known
1225 * e.g. from the container. During decoding, the decoder may
1226 * overwrite those values as required.
1227 */
1228 int coded_width, coded_height;
1229
1230 #if FF_API_ASPECT_EXTENDED
1231 #define FF_ASPECT_EXTENDED 15
1232 #endif
1233
1234 /**
1235 * the number of pictures in a group of pictures, or 0 for intra_only
1236 * - encoding: Set by user.
1237 * - decoding: unused
1238 */
1239 int gop_size;
1240
1241 /**
1242 * Pixel format, see AV_PIX_FMT_xxx.
1243 * May be set by the demuxer if known from headers.
1244 * May be overriden by the decoder if it knows better.
1245 * - encoding: Set by user.
1246 * - decoding: Set by user if known, overridden by libavcodec if known
1247 */
1248 enum AVPixelFormat pix_fmt;
1249
1250 /**
1251 * Motion estimation algorithm used for video coding.
1252 * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
1253 * 8 (umh), 10 (tesa) [7, 8, 10 are x264 specific]
1254 * - encoding: MUST be set by user.
1255 * - decoding: unused
1256 */
1257 int me_method;
1258
1259 /**
1260 * If non NULL, 'draw_horiz_band' is called by the libavcodec
1261 * decoder to draw a horizontal band. It improves cache usage. Not
1262 * all codecs can do that. You must check the codec capabilities
1263 * beforehand.
1264 * When multithreading is used, it may be called from multiple threads
1265 * at the same time; threads might draw different parts of the same AVFrame,
1266 * or multiple AVFrames, and there is no guarantee that slices will be drawn
1267 * in order.
1268 * The function is also used by hardware acceleration APIs.
1269 * It is called at least once during frame decoding to pass
1270 * the data needed for hardware render.
1271 * In that mode instead of pixel data, AVFrame points to
1272 * a structure specific to the acceleration API. The application
1273 * reads the structure and can change some fields to indicate progress
1274 * or mark state.
1275 * - encoding: unused
1276 * - decoding: Set by user.
1277 * @param height the height of the slice
1278 * @param y the y position of the slice
1279 * @param type 1->top field, 2->bottom field, 3->frame
1280 * @param offset offset into the AVFrame.data from which the slice should be read
1281 */
1282 void (*draw_horiz_band)(struct AVCodecContext *s,
1283 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1284 int y, int type, int height);
1285
1286 /**
1287 * callback to negotiate the pixelFormat
1288 * @param fmt is the list of formats which are supported by the codec,
1289 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1290 * The first is always the native one.
1291 * @return the chosen format
1292 * - encoding: unused
1293 * - decoding: Set by user, if not set the native format will be chosen.
1294 */
1295 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1296
1297 /**
1298 * maximum number of B-frames between non-B-frames
1299 * Note: The output will be delayed by max_b_frames+1 relative to the input.
1300 * - encoding: Set by user.
1301 * - decoding: unused
1302 */
1303 int max_b_frames;
1304
1305 /**
1306 * qscale factor between IP and B-frames
1307 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1308 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1309 * - encoding: Set by user.
1310 * - decoding: unused
1311 */
1312 float b_quant_factor;
1313
1314 /** obsolete FIXME remove */
1315 int rc_strategy;
1316 #define FF_RC_STRATEGY_XVID 1
1317
1318 int b_frame_strategy;
1319
1320 /**
1321 * qscale offset between IP and B-frames
1322 * - encoding: Set by user.
1323 * - decoding: unused
1324 */
1325 float b_quant_offset;
1326
1327 /**
1328 * Size of the frame reordering buffer in the decoder.
1329 * For MPEG-2 it is 1 IPB or 0 low delay IP.
1330 * - encoding: Set by libavcodec.
1331 * - decoding: Set by libavcodec.
1332 */
1333 int has_b_frames;
1334
1335 /**
1336 * 0-> h263 quant 1-> mpeg quant
1337 * - encoding: Set by user.
1338 * - decoding: unused
1339 */
1340 int mpeg_quant;
1341
1342 /**
1343 * qscale factor between P and I-frames
1344 * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
1345 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1346 * - encoding: Set by user.
1347 * - decoding: unused
1348 */
1349 float i_quant_factor;
1350
1351 /**
1352 * qscale offset between P and I-frames
1353 * - encoding: Set by user.
1354 * - decoding: unused
1355 */
1356 float i_quant_offset;
1357
1358 /**
1359 * luminance masking (0-> disabled)
1360 * - encoding: Set by user.
1361 * - decoding: unused
1362 */
1363 float lumi_masking;
1364
1365 /**
1366 * temporary complexity masking (0-> disabled)
1367 * - encoding: Set by user.
1368 * - decoding: unused
1369 */
1370 float temporal_cplx_masking;
1371
1372 /**
1373 * spatial complexity masking (0-> disabled)
1374 * - encoding: Set by user.
1375 * - decoding: unused
1376 */
1377 float spatial_cplx_masking;
1378
1379 /**
1380 * p block masking (0-> disabled)
1381 * - encoding: Set by user.
1382 * - decoding: unused
1383 */
1384 float p_masking;
1385
1386 /**
1387 * darkness masking (0-> disabled)
1388 * - encoding: Set by user.
1389 * - decoding: unused
1390 */
1391 float dark_masking;
1392
1393 /**
1394 * slice count
1395 * - encoding: Set by libavcodec.
1396 * - decoding: Set by user (or 0).
1397 */
1398 int slice_count;
1399 /**
1400 * prediction method (needed for huffyuv)
1401 * - encoding: Set by user.
1402 * - decoding: unused
1403 */
1404 int prediction_method;
1405 #define FF_PRED_LEFT 0
1406 #define FF_PRED_PLANE 1
1407 #define FF_PRED_MEDIAN 2
1408
1409 /**
1410 * slice offsets in the frame in bytes
1411 * - encoding: Set/allocated by libavcodec.
1412 * - decoding: Set/allocated by user (or NULL).
1413 */
1414 int *slice_offset;
1415
1416 /**
1417 * sample aspect ratio (0 if unknown)
1418 * That is the width of a pixel divided by the height of the pixel.
1419 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1420 * - encoding: Set by user.
1421 * - decoding: Set by libavcodec.
1422 */
1423 AVRational sample_aspect_ratio;
1424
1425 /**
1426 * motion estimation comparison function
1427 * - encoding: Set by user.
1428 * - decoding: unused
1429 */
1430 int me_cmp;
1431 /**
1432 * subpixel motion estimation comparison function
1433 * - encoding: Set by user.
1434 * - decoding: unused
1435 */
1436 int me_sub_cmp;
1437 /**
1438 * macroblock comparison function (not supported yet)
1439 * - encoding: Set by user.
1440 * - decoding: unused
1441 */
1442 int mb_cmp;
1443 /**
1444 * interlaced DCT comparison function
1445 * - encoding: Set by user.
1446 * - decoding: unused
1447 */
1448 int ildct_cmp;
1449 #define FF_CMP_SAD 0
1450 #define FF_CMP_SSE 1
1451 #define FF_CMP_SATD 2
1452 #define FF_CMP_DCT 3
1453 #define FF_CMP_PSNR 4
1454 #define FF_CMP_BIT 5
1455 #define FF_CMP_RD 6
1456 #define FF_CMP_ZERO 7
1457 #define FF_CMP_VSAD 8
1458 #define FF_CMP_VSSE 9
1459 #define FF_CMP_NSSE 10
1460 #define FF_CMP_DCTMAX 13
1461 #define FF_CMP_DCT264 14
1462 #define FF_CMP_CHROMA 256
1463
1464 /**
1465 * ME diamond size & shape
1466 * - encoding: Set by user.
1467 * - decoding: unused
1468 */
1469 int dia_size;
1470
1471 /**
1472 * amount of previous MV predictors (2a+1 x 2a+1 square)
1473 * - encoding: Set by user.
1474 * - decoding: unused
1475 */
1476 int last_predictor_count;
1477
1478 /**
1479 * prepass for motion estimation
1480 * - encoding: Set by user.
1481 * - decoding: unused
1482 */
1483 int pre_me;
1484
1485 /**
1486 * motion estimation prepass comparison function
1487 * - encoding: Set by user.
1488 * - decoding: unused
1489 */
1490 int me_pre_cmp;
1491
1492 /**
1493 * ME prepass diamond size & shape
1494 * - encoding: Set by user.
1495 * - decoding: unused
1496 */
1497 int pre_dia_size;
1498
1499 /**
1500 * subpel ME quality
1501 * - encoding: Set by user.
1502 * - decoding: unused
1503 */
1504 int me_subpel_quality;
1505
1506 /**
1507 * DTG active format information (additional aspect ratio
1508 * information only used in DVB MPEG-2 transport streams)
1509 * 0 if not set.
1510 *
1511 * - encoding: unused
1512 * - decoding: Set by decoder.
1513 */
1514 int dtg_active_format;
1515 #define FF_DTG_AFD_SAME 8
1516 #define FF_DTG_AFD_4_3 9
1517 #define FF_DTG_AFD_16_9 10
1518 #define FF_DTG_AFD_14_9 11
1519 #define FF_DTG_AFD_4_3_SP_14_9 13
1520 #define FF_DTG_AFD_16_9_SP_14_9 14
1521 #define FF_DTG_AFD_SP_4_3 15
1522
1523 /**
1524 * maximum motion estimation search range in subpel units
1525 * If 0 then no limit.
1526 *
1527 * - encoding: Set by user.
1528 * - decoding: unused
1529 */
1530 int me_range;
1531
1532 /**
1533 * intra quantizer bias
1534 * - encoding: Set by user.
1535 * - decoding: unused
1536 */
1537 int intra_quant_bias;
1538 #define FF_DEFAULT_QUANT_BIAS 999999
1539
1540 /**
1541 * inter quantizer bias
1542 * - encoding: Set by user.
1543 * - decoding: unused
1544 */
1545 int inter_quant_bias;
1546
1547 /**
1548 * slice flags
1549 * - encoding: unused
1550 * - decoding: Set by user.
1551 */
1552 int slice_flags;
1553 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1554 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
1555 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1556
1557 #if FF_API_XVMC
1558 /**
1559 * XVideo Motion Acceleration
1560 * - encoding: forbidden
1561 * - decoding: set by decoder
1562 * @deprecated XvMC support is slated for removal.
1563 */
1564 attribute_deprecated int xvmc_acceleration;
1565 #endif /* FF_API_XVMC */
1566
1567 /**
1568 * macroblock decision mode
1569 * - encoding: Set by user.
1570 * - decoding: unused
1571 */
1572 int mb_decision;
1573 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1574 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1575 #define FF_MB_DECISION_RD 2 ///< rate distortion
1576
1577 /**
1578 * custom intra quantization matrix
1579 * - encoding: Set by user, can be NULL.
1580 * - decoding: Set by libavcodec.
1581 */
1582 uint16_t *intra_matrix;
1583
1584 /**
1585 * custom inter quantization matrix
1586 * - encoding: Set by user, can be NULL.
1587 * - decoding: Set by libavcodec.
1588 */
1589 uint16_t *inter_matrix;
1590
1591 /**
1592 * scene change detection threshold
1593 * 0 is default, larger means fewer detected scene changes.
1594 * - encoding: Set by user.
1595 * - decoding: unused
1596 */
1597 int scenechange_threshold;
1598
1599 /**
1600 * noise reduction strength
1601 * - encoding: Set by user.
1602 * - decoding: unused
1603 */
1604 int noise_reduction;
1605
1606 /**
1607 * Motion estimation threshold below which no motion estimation is
1608 * performed, but instead the user specified motion vectors are used.
1609 *
1610 * - encoding: Set by user.
1611 * - decoding: unused
1612 */
1613 int me_threshold;
1614
1615 /**
1616 * Macroblock threshold below which the user specified macroblock types will be used.
1617 * - encoding: Set by user.
1618 * - decoding: unused
1619 */
1620 int mb_threshold;
1621
1622 /**
1623 * precision of the intra DC coefficient - 8
1624 * - encoding: Set by user.
1625 * - decoding: unused
1626 */
1627 int intra_dc_precision;
1628
1629 /**
1630 * Number of macroblock rows at the top which are skipped.
1631 * - encoding: unused
1632 * - decoding: Set by user.
1633 */
1634 int skip_top;
1635
1636 /**
1637 * Number of macroblock rows at the bottom which are skipped.
1638 * - encoding: unused
1639 * - decoding: Set by user.
1640 */
1641 int skip_bottom;
1642
1643 /**
1644 * Border processing masking, raises the quantizer for mbs on the borders
1645 * of the picture.
1646 * - encoding: Set by user.
1647 * - decoding: unused
1648 */
1649 float border_masking;
1650
1651 /**
1652 * minimum MB lagrange multipler
1653 * - encoding: Set by user.
1654 * - decoding: unused
1655 */
1656 int mb_lmin;
1657
1658 /**
1659 * maximum MB lagrange multipler
1660 * - encoding: Set by user.
1661 * - decoding: unused
1662 */
1663 int mb_lmax;
1664
1665 /**
1666 *
1667 * - encoding: Set by user.
1668 * - decoding: unused
1669 */
1670 int me_penalty_compensation;
1671
1672 /**
1673 *
1674 * - encoding: Set by user.
1675 * - decoding: unused
1676 */
1677 int bidir_refine;
1678
1679 /**
1680 *
1681 * - encoding: Set by user.
1682 * - decoding: unused
1683 */
1684 int brd_scale;
1685
1686 /**
1687 * minimum GOP size
1688 * - encoding: Set by user.
1689 * - decoding: unused
1690 */
1691 int keyint_min;
1692
1693 /**
1694 * number of reference frames
1695 * - encoding: Set by user.
1696 * - decoding: Set by lavc.
1697 */
1698 int refs;
1699
1700 /**
1701 * chroma qp offset from luma
1702 * - encoding: Set by user.
1703 * - decoding: unused
1704 */
1705 int chromaoffset;
1706
1707 /**
1708 * Multiplied by qscale for each frame and added to scene_change_score.
1709 * - encoding: Set by user.
1710 * - decoding: unused
1711 */
1712 int scenechange_factor;
1713
1714 /**
1715 *
1716 * Note: Value depends upon the compare function used for fullpel ME.
1717 * - encoding: Set by user.
1718 * - decoding: unused
1719 */
1720 int mv0_threshold;
1721
1722 /**
1723 * Adjust sensitivity of b_frame_strategy 1.
1724 * - encoding: Set by user.
1725 * - decoding: unused
1726 */
1727 int b_sensitivity;
1728
1729 /**
1730 * Chromaticity coordinates of the source primaries.
1731 * - encoding: Set by user
1732 * - decoding: Set by libavcodec
1733 */
1734 enum AVColorPrimaries color_primaries;
1735
1736 /**
1737 * Color Transfer Characteristic.
1738 * - encoding: Set by user
1739 * - decoding: Set by libavcodec
1740 */
1741 enum AVColorTransferCharacteristic color_trc;
1742
1743 /**
1744 * YUV colorspace type.
1745 * - encoding: Set by user
1746 * - decoding: Set by libavcodec
1747 */
1748 enum AVColorSpace colorspace;
1749
1750 /**
1751 * MPEG vs JPEG YUV range.
1752 * - encoding: Set by user
1753 * - decoding: Set by libavcodec
1754 */
1755 enum AVColorRange color_range;
1756
1757 /**
1758 * This defines the location of chroma samples.
1759 * - encoding: Set by user
1760 * - decoding: Set by libavcodec
1761 */
1762 enum AVChromaLocation chroma_sample_location;
1763
1764 /**
1765 * Number of slices.
1766 * Indicates number of picture subdivisions. Used for parallelized
1767 * decoding.
1768 * - encoding: Set by user
1769 * - decoding: unused
1770 */
1771 int slices;
1772
1773 /** Field order
1774 * - encoding: set by libavcodec
1775 * - decoding: Set by libavcodec
1776 */
1777 enum AVFieldOrder field_order;
1778
1779 /* audio only */
1780 int sample_rate; ///< samples per second
1781 int channels; ///< number of audio channels
1782
1783 /**
1784 * audio sample format
1785 * - encoding: Set by user.
1786 * - decoding: Set by libavcodec.
1787 */
1788 enum AVSampleFormat sample_fmt; ///< sample format
1789
1790 /* The following data should not be initialized. */
1791 /**
1792 * Number of samples per channel in an audio frame.
1793 *
1794 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1795 * except the last must contain exactly frame_size samples per channel.
1796 * May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1797 * frame size is not restricted.
1798 * - decoding: may be set by some decoders to indicate constant frame size
1799 */
1800 int frame_size;
1801
1802 /**
1803 * Frame counter, set by libavcodec.
1804 *
1805 * - decoding: total number of frames returned from the decoder so far.
1806 * - encoding: total number of frames passed to the encoder so far.
1807 *
1808 * @note the counter is not incremented if encoding/decoding resulted in
1809 * an error.
1810 */
1811 int frame_number;
1812
1813 /**
1814 * number of bytes per packet if constant and known or 0
1815 * Used by some WAV based audio codecs.
1816 */
1817 int block_align;
1818
1819 /**
1820 * Audio cutoff bandwidth (0 means "automatic")
1821 * - encoding: Set by user.
1822 * - decoding: unused
1823 */
1824 int cutoff;
1825
1826 #if FF_API_REQUEST_CHANNELS
1827 /**
1828 * Decoder should decode to this many channels if it can (0 for default)
1829 * - encoding: unused
1830 * - decoding: Set by user.
1831 * @deprecated Deprecated in favor of request_channel_layout.
1832 */
1833 attribute_deprecated int request_channels;
1834 #endif
1835
1836 /**
1837 * Audio channel layout.
1838 * - encoding: set by user.
1839 * - decoding: set by libavcodec.
1840 */
1841 uint64_t channel_layout;
1842
1843 /**
1844 * Request decoder to use this channel layout if it can (0 for default)
1845 * - encoding: unused
1846 * - decoding: Set by user.
1847 */
1848 uint64_t request_channel_layout;
1849
1850 /**
1851 * Type of service that the audio stream conveys.
1852 * - encoding: Set by user.
1853 * - decoding: Set by libavcodec.
1854 */
1855 enum AVAudioServiceType audio_service_type;
1856
1857 /**
1858 * Used to request a sample format from the decoder.
1859 * - encoding: unused.
1860 * - decoding: Set by user.
1861 */
1862 enum AVSampleFormat request_sample_fmt;
1863
1864 #if FF_API_GET_BUFFER
1865 /**
1866 * Called at the beginning of each frame to get a buffer for it.
1867 *
1868 * The function will set AVFrame.data[], AVFrame.linesize[].
1869 * AVFrame.extended_data[] must also be set, but it should be the same as
1870 * AVFrame.data[] except for planar audio with more channels than can fit
1871 * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
1872 * many data pointers as it can hold.
1873 *
1874 * if CODEC_CAP_DR1 is not set then get_buffer() must call
1875 * avcodec_default_get_buffer() instead of providing buffers allocated by
1876 * some other means.
1877 *
1878 * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
1879 * need it. avcodec_default_get_buffer() aligns the output buffer properly,
1880 * but if get_buffer() is overridden then alignment considerations should
1881 * be taken into account.
1882 *
1883 * @see avcodec_default_get_buffer()
1884 *
1885 * Video:
1886 *
1887 * If pic.reference is set then the frame will be read later by libavcodec.
1888 * avcodec_align_dimensions2() should be used to find the required width and
1889 * height, as they normally need to be rounded up to the next multiple of 16.
1890 *
1891 * If frame multithreading is used and thread_safe_callbacks is set,
1892 * it may be called from a different thread, but not from more than one at
1893 * once. Does not need to be reentrant.
1894 *
1895 * @see release_buffer(), reget_buffer()
1896 * @see avcodec_align_dimensions2()
1897 *
1898 * Audio:
1899 *
1900 * Decoders request a buffer of a particular size by setting
1901 * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
1902 * however, utilize only part of the buffer by setting AVFrame.nb_samples
1903 * to a smaller value in the output frame.
1904 *
1905 * Decoders cannot use the buffer after returning from
1906 * avcodec_decode_audio4(), so they will not call release_buffer(), as it
1907 * is assumed to be released immediately upon return. In some rare cases,
1908 * a decoder may need to call get_buffer() more than once in a single
1909 * call to avcodec_decode_audio4(). In that case, when get_buffer() is
1910 * called again after it has already been called once, the previously
1911 * acquired buffer is assumed to be released at that time and may not be
1912 * reused by the decoder.
1913 *
1914 * As a convenience, av_samples_get_buffer_size() and
1915 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
1916 * functions to find the required data size and to fill data pointers and
1917 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
1918 * since all planes must be the same size.
1919 *
1920 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
1921 *
1922 * - encoding: unused
1923 * - decoding: Set by libavcodec, user can override.
1924 *
1925 * @deprecated use get_buffer2()
1926 */
1927 attribute_deprecated
1928 int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
1929
1930 /**
1931 * Called to release buffers which were allocated with get_buffer.
1932 * A released buffer can be reused in get_buffer().
1933 * pic.data[*] must be set to NULL.
1934 * May be called from a different thread if frame multithreading is used,
1935 * but not by more than one thread at once, so does not need to be reentrant.
1936 * - encoding: unused
1937 * - decoding: Set by libavcodec, user can override.
1938 *
1939 * @deprecated custom freeing callbacks should be set from get_buffer2()
1940 */
1941 attribute_deprecated
1942 void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
1943
1944 /**
1945 * Called at the beginning of a frame to get cr buffer for it.
1946 * Buffer type (size, hints) must be the same. libavcodec won't check it.
1947 * libavcodec will pass previous buffer in pic, function should return
1948 * same buffer or new buffer with old frame "painted" into it.
1949 * If pic.data[0] == NULL must behave like get_buffer().
1950 * if CODEC_CAP_DR1 is not set then reget_buffer() must call
1951 * avcodec_default_reget_buffer() instead of providing buffers allocated by
1952 * some other means.
1953 * - encoding: unused
1954 * - decoding: Set by libavcodec, user can override.
1955 */
1956 attribute_deprecated
1957 int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
1958 #endif
1959
1960 /**
1961 * This callback is called at the beginning of each frame to get data
1962 * buffer(s) for it. There may be one contiguous buffer for all the data or
1963 * there may be a buffer per each data plane or anything in between. What
1964 * this means is, you may set however many entries in buf[] you feel necessary.
1965 * Each buffer must be reference-counted using the AVBuffer API (see description
1966 * of buf[] below).
1967 *
1968 * The following fields will be set in the frame before this callback is
1969 * called:
1970 * - format
1971 * - width, height (video only)
1972 * - sample_rate, channel_layout, nb_samples (audio only)
1973 * Their values may differ from the corresponding values in
1974 * AVCodecContext. This callback must use the frame values, not the codec
1975 * context values, to calculate the required buffer size.
1976 *
1977 * This callback must fill the following fields in the frame:
1978 * - data[]
1979 * - linesize[]
1980 * - extended_data:
1981 * * if the data is planar audio with more than 8 channels, then this
1982 * callback must allocate and fill extended_data to contain all pointers
1983 * to all data planes. data[] must hold as many pointers as it can.
1984 * extended_data must be allocated with av_malloc() and will be freed in
1985 * av_frame_unref().
1986 * * otherwise exended_data must point to data
1987 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
1988 * the frame's data and extended_data pointers must be contained in these. That
1989 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
1990 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
1991 * and av_buffer_ref().
1992 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
1993 * this callback and filled with the extra buffers if there are more
1994 * buffers than buf[] can hold. extended_buf will be freed in
1995 * av_frame_unref().
1996 *
1997 * If CODEC_CAP_DR1 is not set then get_buffer2() must call
1998 * avcodec_default_get_buffer2() instead of providing buffers allocated by
1999 * some other means.
2000 *
2001 * Each data plane must be aligned to the maximum required by the target
2002 * CPU.
2003 *
2004 * @see avcodec_default_get_buffer2()
2005 *
2006 * Video:
2007 *
2008 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2009 * (read and/or written to if it is writable) later by libavcodec.
2010 *
2011 * avcodec_align_dimensions2() should be used to find the required width and
2012 * height, as they normally need to be rounded up to the next multiple of 16.
2013 *
2014 * If frame multithreading is used and thread_safe_callbacks is set,
2015 * this callback may be called from a different thread, but not from more
2016 * than one at once. Does not need to be reentrant.
2017 *
2018 * @see avcodec_align_dimensions2()
2019 *
2020 * Audio:
2021 *
2022 * Decoders request a buffer of a particular size by setting
2023 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2024 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2025 * to a smaller value in the output frame.
2026 *
2027 * As a convenience, av_samples_get_buffer_size() and
2028 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2029 * functions to find the required data size and to fill data pointers and
2030 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2031 * since all planes must be the same size.
2032 *
2033 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2034 *
2035 * - encoding: unused
2036 * - decoding: Set by libavcodec, user can override.
2037 */
2038 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2039
2040 /**
2041 * If non-zero, the decoded audio and video frames returned from
2042 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2043 * and are valid indefinitely. The caller must free them with
2044 * av_frame_unref() when they are not needed anymore.
2045 * Otherwise, the decoded frames must not be freed by the caller and are
2046 * only valid until the next decode call.
2047 *
2048 * - encoding: unused
2049 * - decoding: set by the caller before avcodec_open2().
2050 */
2051 int refcounted_frames;
2052
2053 /* - encoding parameters */
2054 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2055 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2056
2057 /**
2058 * minimum quantizer
2059 * - encoding: Set by user.
2060 * - decoding: unused
2061 */
2062 int qmin;
2063
2064 /**
2065 * maximum quantizer
2066 * - encoding: Set by user.
2067 * - decoding: unused
2068 */
2069 int qmax;
2070
2071 /**
2072 * maximum quantizer difference between frames
2073 * - encoding: Set by user.
2074 * - decoding: unused
2075 */
2076 int max_qdiff;
2077
2078 /**
2079 * ratecontrol qmin qmax limiting method
2080 * 0-> clipping, 1-> use a nice continuous function to limit qscale wthin qmin/qmax.
2081 * - encoding: Set by user.
2082 * - decoding: unused
2083 */
2084 float rc_qsquish;
2085
2086 float rc_qmod_amp;
2087 int rc_qmod_freq;
2088
2089 /**
2090 * decoder bitstream buffer size
2091 * - encoding: Set by user.
2092 * - decoding: unused
2093 */
2094 int rc_buffer_size;
2095
2096 /**
2097 * ratecontrol override, see RcOverride
2098 * - encoding: Allocated/set/freed by user.
2099 * - decoding: unused
2100 */
2101 int rc_override_count;
2102 RcOverride *rc_override;
2103
2104 /**
2105 * rate control equation
2106 * - encoding: Set by user
2107 * - decoding: unused
2108 */
2109 const char *rc_eq;
2110
2111 /**
2112 * maximum bitrate
2113 * - encoding: Set by user.
2114 * - decoding: unused
2115 */
2116 int rc_max_rate;
2117
2118 /**
2119 * minimum bitrate
2120 * - encoding: Set by user.
2121 * - decoding: unused
2122 */
2123 int rc_min_rate;
2124
2125 float rc_buffer_aggressivity;
2126
2127 /**
2128 * initial complexity for pass1 ratecontrol
2129 * - encoding: Set by user.
2130 * - decoding: unused
2131 */
2132 float rc_initial_cplx;
2133
2134 /**
2135 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2136 * - encoding: Set by user.
2137 * - decoding: unused.
2138 */
2139 float rc_max_available_vbv_use;
2140
2141 /**
2142 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2143 * - encoding: Set by user.
2144 * - decoding: unused.
2145 */
2146 float rc_min_vbv_overflow_use;
2147
2148 /**
2149 * Number of bits which should be loaded into the rc buffer before decoding starts.
2150 * - encoding: Set by user.
2151 * - decoding: unused
2152 */
2153 int rc_initial_buffer_occupancy;
2154
2155 #define FF_CODER_TYPE_VLC 0
2156 #define FF_CODER_TYPE_AC 1
2157 #define FF_CODER_TYPE_RAW 2
2158 #define FF_CODER_TYPE_RLE 3
2159 #define FF_CODER_TYPE_DEFLATE 4
2160 /**
2161 * coder type
2162 * - encoding: Set by user.
2163 * - decoding: unused
2164 */
2165 int coder_type;
2166
2167 /**
2168 * context model
2169 * - encoding: Set by user.
2170 * - decoding: unused
2171 */
2172 int context_model;
2173
2174 /**
2175 * minimum Lagrange multipler
2176 * - encoding: Set by user.
2177 * - decoding: unused
2178 */
2179 int lmin;
2180
2181 /**
2182 * maximum Lagrange multipler
2183 * - encoding: Set by user.
2184 * - decoding: unused
2185 */
2186 int lmax;
2187
2188 /**
2189 * frame skip threshold
2190 * - encoding: Set by user.
2191 * - decoding: unused
2192 */
2193 int frame_skip_threshold;
2194
2195 /**
2196 * frame skip factor
2197 * - encoding: Set by user.
2198 * - decoding: unused
2199 */
2200 int frame_skip_factor;
2201
2202 /**
2203 * frame skip exponent
2204 * - encoding: Set by user.
2205 * - decoding: unused
2206 */
2207 int frame_skip_exp;
2208
2209 /**
2210 * frame skip comparison function
2211 * - encoding: Set by user.
2212 * - decoding: unused
2213 */
2214 int frame_skip_cmp;
2215
2216 /**
2217 * trellis RD quantization
2218 * - encoding: Set by user.
2219 * - decoding: unused
2220 */
2221 int trellis;
2222
2223 /**
2224 * - encoding: Set by user.
2225 * - decoding: unused
2226 */
2227 int min_prediction_order;
2228
2229 /**
2230 * - encoding: Set by user.
2231 * - decoding: unused
2232 */
2233 int max_prediction_order;
2234
2235 /**
2236 * GOP timecode frame start number, in non drop frame format
2237 * - encoding: Set by user.
2238 * - decoding: unused
2239 */
2240 int64_t timecode_frame_start;
2241
2242 /* The RTP callback: This function is called */
2243 /* every time the encoder has a packet to send. */
2244 /* It depends on the encoder if the data starts */
2245 /* with a Start Code (it should). H.263 does. */
2246 /* mb_nb contains the number of macroblocks */
2247 /* encoded in the RTP payload. */
2248 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2249
2250 int rtp_payload_size; /* The size of the RTP payload: the coder will */
2251 /* do its best to deliver a chunk with size */
2252 /* below rtp_payload_size, the chunk will start */
2253 /* with a start code on some codecs like H.263. */
2254 /* This doesn't take account of any particular */
2255 /* headers inside the transmitted RTP payload. */
2256
2257 /* statistics, used for 2-pass encoding */
2258 int mv_bits;
2259 int header_bits;
2260 int i_tex_bits;
2261 int p_tex_bits;
2262 int i_count;
2263 int p_count;
2264 int skip_count;
2265 int misc_bits;
2266
2267 /**
2268 * number of bits used for the previously encoded frame
2269 * - encoding: Set by libavcodec.
2270 * - decoding: unused
2271 */
2272 int frame_bits;
2273
2274 /**
2275 * pass1 encoding statistics output buffer
2276 * - encoding: Set by libavcodec.
2277 * - decoding: unused
2278 */
2279 char *stats_out;
2280
2281 /**
2282 * pass2 encoding statistics input buffer
2283 * Concatenated stuff from stats_out of pass1 should be placed here.
2284 * - encoding: Allocated/set/freed by user.
2285 * - decoding: unused
2286 */
2287 char *stats_in;
2288
2289 /**
2290 * Work around bugs in encoders which sometimes cannot be detected automatically.
2291 * - encoding: Set by user
2292 * - decoding: Set by user
2293 */
2294 int workaround_bugs;
2295 #define FF_BUG_AUTODETECT 1 ///< autodetection
2296 #if FF_API_OLD_MSMPEG4
2297 #define FF_BUG_OLD_MSMPEG4 2
2298 #endif
2299 #define FF_BUG_XVID_ILACE 4
2300 #define FF_BUG_UMP4 8
2301 #define FF_BUG_NO_PADDING 16
2302 #define FF_BUG_AMV 32
2303 #if FF_API_AC_VLC
2304 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2305 #endif
2306 #define FF_BUG_QPEL_CHROMA 64
2307 #define FF_BUG_STD_QPEL 128
2308 #define FF_BUG_QPEL_CHROMA2 256
2309 #define FF_BUG_DIRECT_BLOCKSIZE 512
2310 #define FF_BUG_EDGE 1024
2311 #define FF_BUG_HPEL_CHROMA 2048
2312 #define FF_BUG_DC_CLIP 4096
2313 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2314 #define FF_BUG_TRUNCATED 16384
2315
2316 /**
2317 * strictly follow the standard (MPEG4, ...).
2318 * - encoding: Set by user.
2319 * - decoding: Set by user.
2320 * Setting this to STRICT or higher means the encoder and decoder will
2321 * generally do stupid things, whereas setting it to unofficial or lower
2322 * will mean the encoder might produce output that is not supported by all
2323 * spec-compliant decoders. Decoders don't differentiate between normal,
2324 * unofficial and experimental (that is, they always try to decode things
2325 * when they can) unless they are explicitly asked to behave stupidly
2326 * (=strictly conform to the specs)
2327 */
2328 int strict_std_compliance;
2329 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2330 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2331 #define FF_COMPLIANCE_NORMAL 0
2332 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2333 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2334
2335 /**
2336 * error concealment flags
2337 * - encoding: unused
2338 * - decoding: Set by user.
2339 */
2340 int error_concealment;
2341 #define FF_EC_GUESS_MVS 1
2342 #define FF_EC_DEBLOCK 2
2343
2344 /**
2345 * debug
2346 * - encoding: Set by user.
2347 * - decoding: Set by user.
2348 */
2349 int debug;
2350 #define FF_DEBUG_PICT_INFO 1
2351 #define FF_DEBUG_RC 2
2352 #define FF_DEBUG_BITSTREAM 4
2353 #define FF_DEBUG_MB_TYPE 8
2354 #define FF_DEBUG_QP 16
2355 #if FF_API_DEBUG_MV
2356 /**
2357 * @deprecated this option does nothing
2358 */
2359 #define FF_DEBUG_MV 32
2360 #endif
2361 #define FF_DEBUG_DCT_COEFF 0x00000040
2362 #define FF_DEBUG_SKIP 0x00000080
2363 #define FF_DEBUG_STARTCODE 0x00000100
2364 #define FF_DEBUG_PTS 0x00000200
2365 #define FF_DEBUG_ER 0x00000400
2366 #define FF_DEBUG_MMCO 0x00000800
2367 #define FF_DEBUG_BUGS 0x00001000
2368 #if FF_API_DEBUG_MV
2369 #define FF_DEBUG_VIS_QP 0x00002000
2370 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2371 #endif
2372 #define FF_DEBUG_BUFFERS 0x00008000
2373 #define FF_DEBUG_THREADS 0x00010000
2374
2375 #if FF_API_DEBUG_MV
2376 /**
2377 * @deprecated this option does not have any effect
2378 */
2379 attribute_deprecated
2380 int debug_mv;
2381 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2382 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2383 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2384 #endif
2385
2386 /**
2387 * Error recognition; may misdetect some more or less valid parts as errors.
2388 * - encoding: unused
2389 * - decoding: Set by user.
2390 */
2391 int err_recognition;
2392
2393 /**
2394 * Verify checksums embedded in the bitstream (could be of either encoded or
2395 * decoded data, depending on the codec) and print an error message on mismatch.
2396 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2397 * decoder returning an error.
2398 */
2399 #define AV_EF_CRCCHECK (1<<0)
2400 #define AV_EF_BITSTREAM (1<<1)
2401 #define AV_EF_BUFFER (1<<2)
2402 #define AV_EF_EXPLODE (1<<3)
2403
2404 /**
2405 * opaque 64bit number (generally a PTS) that will be reordered and
2406 * output in AVFrame.reordered_opaque
2407 * @deprecated in favor of pkt_pts
2408 * - encoding: unused
2409 * - decoding: Set by user.
2410 */
2411 int64_t reordered_opaque;
2412
2413 /**
2414 * Hardware accelerator in use
2415 * - encoding: unused.
2416 * - decoding: Set by libavcodec
2417 */
2418 struct AVHWAccel *hwaccel;
2419
2420 /**
2421 * Hardware accelerator context.
2422 * For some hardware accelerators, a global context needs to be
2423 * provided by the user. In that case, this holds display-dependent
2424 * data Libav cannot instantiate itself. Please refer to the
2425 * Libav HW accelerator documentation to know how to fill this
2426 * is. e.g. for VA API, this is a struct vaapi_context.
2427 * - encoding: unused
2428 * - decoding: Set by user
2429 */
2430 void *hwaccel_context;
2431
2432 /**
2433 * error
2434 * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
2435 * - decoding: unused
2436 */
2437 uint64_t error[AV_NUM_DATA_POINTERS];
2438
2439 /**
2440 * DCT algorithm, see FF_DCT_* below
2441 * - encoding: Set by user.
2442 * - decoding: unused
2443 */
2444 int dct_algo;
2445 #define FF_DCT_AUTO 0
2446 #define FF_DCT_FASTINT 1
2447 #define FF_DCT_INT 2
2448 #define FF_DCT_MMX 3
2449 #define FF_DCT_ALTIVEC 5
2450 #define FF_DCT_FAAN 6
2451
2452 /**
2453 * IDCT algorithm, see FF_IDCT_* below.
2454 * - encoding: Set by user.
2455 * - decoding: Set by user.
2456 */
2457 int idct_algo;
2458 #define FF_IDCT_AUTO 0
2459 #define FF_IDCT_INT 1
2460 #define FF_IDCT_SIMPLE 2
2461 #define FF_IDCT_SIMPLEMMX 3
2462 #define FF_IDCT_ARM 7
2463 #define FF_IDCT_ALTIVEC 8
2464 #if FF_API_ARCH_SH4
2465 #define FF_IDCT_SH4 9
2466 #endif
2467 #define FF_IDCT_SIMPLEARM 10
2468 #define FF_IDCT_IPP 13
2469 #define FF_IDCT_XVIDMMX 14
2470 #define FF_IDCT_SIMPLEARMV5TE 16
2471 #define FF_IDCT_SIMPLEARMV6 17
2472 #if FF_API_ARCH_SPARC
2473 #define FF_IDCT_SIMPLEVIS 18
2474 #endif
2475 #define FF_IDCT_FAAN 20
2476 #define FF_IDCT_SIMPLENEON 22
2477 #if FF_API_ARCH_ALPHA
2478 #define FF_IDCT_SIMPLEALPHA 23
2479 #endif
2480
2481 /**
2482 * bits per sample/pixel from the demuxer (needed for huffyuv).
2483 * - encoding: Set by libavcodec.
2484 * - decoding: Set by user.
2485 */
2486 int bits_per_coded_sample;
2487
2488 /**
2489 * Bits per sample/pixel of internal libavcodec pixel/sample format.
2490 * - encoding: set by user.
2491 * - decoding: set by libavcodec.
2492 */
2493 int bits_per_raw_sample;
2494
2495 #if FF_API_LOWRES
2496 /**
2497 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2498 * - encoding: unused
2499 * - decoding: Set by user.
2500 *
2501 * @deprecated use decoder private options instead
2502 */
2503 attribute_deprecated int lowres;
2504 #endif
2505
2506 /**
2507 * the picture in the bitstream
2508 * - encoding: Set by libavcodec.
2509 * - decoding: unused
2510 */
2511 AVFrame *coded_frame;
2512
2513 /**
2514 * thread count
2515 * is used to decide how many independent tasks should be passed to execute()
2516 * - encoding: Set by user.
2517 * - decoding: Set by user.
2518 */
2519 int thread_count;
2520
2521 /**
2522 * Which multithreading methods to use.
2523 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2524 * so clients which cannot provide future frames should not use it.
2525 *
2526 * - encoding: Set by user, otherwise the default is used.
2527 * - decoding: Set by user, otherwise the default is used.
2528 */
2529 int thread_type;
2530 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2531 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2532
2533 /**
2534 * Which multithreading methods are in use by the codec.
2535 * - encoding: Set by libavcodec.
2536 * - decoding: Set by libavcodec.
2537 */
2538 int active_thread_type;
2539
2540 /**
2541 * Set by the client if its custom get_buffer() callback can be called
2542 * synchronously from another thread, which allows faster multithreaded decoding.
2543 * draw_horiz_band() will be called from other threads regardless of this setting.
2544 * Ignored if the default get_buffer() is used.
2545 * - encoding: Set by user.
2546 * - decoding: Set by user.
2547 */
2548 int thread_safe_callbacks;
2549
2550 /**
2551 * The codec may call this to execute several independent things.
2552 * It will return only after finishing all tasks.
2553 * The user may replace this with some multithreaded implementation,
2554 * the default implementation will execute the parts serially.
2555 * @param count the number of things to execute
2556 * - encoding: Set by libavcodec, user can override.
2557 * - decoding: Set by libavcodec, user can override.
2558 */
2559 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2560
2561 /**
2562 * The codec may call this to execute several independent things.
2563 * It will return only after finishing all tasks.
2564 * The user may replace this with some multithreaded implementation,
2565 * the default implementation will execute the parts serially.
2566 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2567 * @param c context passed also to func
2568 * @param count the number of things to execute
2569 * @param arg2 argument passed unchanged to func
2570 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2571 * @param func function that will be called count times, with jobnr from 0 to count-1.
2572 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2573 * two instances of func executing at the same time will have the same threadnr.
2574 * @return always 0 currently, but code should handle a future improvement where when any call to func
2575 * returns < 0 no further calls to func may be done and < 0 is returned.
2576 * - encoding: Set by libavcodec, user can override.
2577 * - decoding: Set by libavcodec, user can override.
2578 */
2579 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2580
2581 #if FF_API_THREAD_OPAQUE
2582 /**
2583 * @deprecated this field should not be used from outside of lavc
2584 */
2585 attribute_deprecated
2586 void *thread_opaque;
2587 #endif
2588
2589 /**
2590 * noise vs. sse weight for the nsse comparsion function
2591 * - encoding: Set by user.
2592 * - decoding: unused
2593 */
2594 int nsse_weight;
2595
2596 /**
2597 * profile
2598 * - encoding: Set by user.
2599 * - decoding: Set by libavcodec.
2600 */
2601 int profile;
2602 #define FF_PROFILE_UNKNOWN -99
2603 #define FF_PROFILE_RESERVED -100
2604
2605 #define FF_PROFILE_AAC_MAIN 0
2606 #define FF_PROFILE_AAC_LOW 1
2607 #define FF_PROFILE_AAC_SSR 2
2608 #define FF_PROFILE_AAC_LTP 3
2609 #define FF_PROFILE_AAC_HE 4
2610 #define FF_PROFILE_AAC_HE_V2 28
2611 #define FF_PROFILE_AAC_LD 22
2612 #define FF_PROFILE_AAC_ELD 38
2613 #define FF_PROFILE_MPEG2_AAC_LOW 128
2614 #define FF_PROFILE_MPEG2_AAC_HE 131
2615
2616 #define FF_PROFILE_DTS 20
2617 #define FF_PROFILE_DTS_ES 30
2618 #define FF_PROFILE_DTS_96_24 40
2619 #define FF_PROFILE_DTS_HD_HRA 50
2620 #define FF_PROFILE_DTS_HD_MA 60
2621
2622 #define FF_PROFILE_MPEG2_422 0
2623 #define FF_PROFILE_MPEG2_HIGH 1
2624 #define FF_PROFILE_MPEG2_SS 2
2625 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2626 #define FF_PROFILE_MPEG2_MAIN 4
2627 #define FF_PROFILE_MPEG2_SIMPLE 5
2628
2629 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2630 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2631
2632 #define FF_PROFILE_H264_BASELINE 66
2633 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2634 #define FF_PROFILE_H264_MAIN 77
2635 #define FF_PROFILE_H264_EXTENDED 88
2636 #define FF_PROFILE_H264_HIGH 100
2637 #define FF_PROFILE_H264_HIGH_10 110
2638 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2639 #define FF_PROFILE_H264_HIGH_422 122
2640 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2641 #define FF_PROFILE_H264_HIGH_444 144
2642 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2643 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2644 #define FF_PROFILE_H264_CAVLC_444 44
2645
2646 #define FF_PROFILE_VC1_SIMPLE 0
2647 #define FF_PROFILE_VC1_MAIN 1
2648 #define FF_PROFILE_VC1_COMPLEX 2
2649 #define FF_PROFILE_VC1_ADVANCED 3
2650
2651 #define FF_PROFILE_MPEG4_SIMPLE 0
2652 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2653 #define FF_PROFILE_MPEG4_CORE 2
2654 #define FF_PROFILE_MPEG4_MAIN 3
2655 #define FF_PROFILE_MPEG4_N_BIT 4
2656 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2657 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2658 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2659 #define FF_PROFILE_MPEG4_HYBRID 8
2660 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2661 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2662 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2663 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2664 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2665 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2666 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2667
2668 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 0
2669 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 1
2670 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 2
2671 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2672 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2673
2674
2675 #define FF_PROFILE_HEVC_MAIN 1
2676 #define FF_PROFILE_HEVC_MAIN_10 2
2677 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2678
2679 /**
2680 * level
2681 * - encoding: Set by user.
2682 * - decoding: Set by libavcodec.
2683 */
2684 int level;
2685 #define FF_LEVEL_UNKNOWN -99
2686
2687 /**
2688 *
2689 * - encoding: unused
2690 * - decoding: Set by user.
2691 */
2692 enum AVDiscard skip_loop_filter;
2693
2694 /**
2695 *
2696 * - encoding: unused
2697 * - decoding: Set by user.
2698 */
2699 enum AVDiscard skip_idct;
2700
2701 /**
2702 *
2703 * - encoding: unused
2704 * - decoding: Set by user.
2705 */
2706 enum AVDiscard skip_frame;
2707
2708 /**
2709 * Header containing style information for text subtitles.
2710 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2711 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2712 * the Format line following. It shouldn't include any Dialogue line.
2713 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2714 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2715 */
2716 uint8_t *subtitle_header;
2717 int subtitle_header_size;
2718
2719 #if FF_API_ERROR_RATE
2720 /**
2721 * @deprecated use the 'error_rate' private AVOption of the mpegvideo
2722 * encoders
2723 */
2724 attribute_deprecated
2725 int error_rate;
2726 #endif
2727
2728 #if FF_API_CODEC_PKT
2729 /**
2730 * @deprecated this field is not supposed to be accessed from outside lavc
2731 */
2732 attribute_deprecated
2733 AVPacket *pkt;
2734 #endif
2735
2736 /**
2737 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2738 * Used for compliant TS muxing.
2739 * - encoding: Set by libavcodec.
2740 * - decoding: unused.
2741 */
2742 uint64_t vbv_delay;
2743
2744 /**
2745 * Encoding only. Allow encoders to output packets that do not contain any
2746 * encoded data, only side data.
2747 *
2748 * Some encoders need to output such packets, e.g. to update some stream
2749 * parameters at the end of encoding.
2750 *
2751 * All callers are strongly recommended to set this option to 1 and update
2752 * their code to deal with such packets, since this behaviour may become
2753 * always enabled in the future (then this option will be deprecated and
2754 * later removed). To avoid ABI issues when this happens, the callers should
2755 * use AVOptions to set this field.
2756 */
2757 int side_data_only_packets;
2758 } AVCodecContext;
2759
2760 /**
2761 * AVProfile.
2762 */
2763 typedef struct AVProfile {
2764 int profile;
2765 const char *name; ///< short name for the profile
2766 } AVProfile;
2767
2768 typedef struct AVCodecDefault AVCodecDefault;
2769
2770 struct AVSubtitle;
2771
2772 /**
2773 * AVCodec.
2774 */
2775 typedef struct AVCodec {
2776 /**
2777 * Name of the codec implementation.
2778 * The name is globally unique among encoders and among decoders (but an
2779 * encoder and a decoder can share the same name).
2780 * This is the primary way to find a codec from the user perspective.
2781 */
2782 const char *name;
2783 /**
2784 * Descriptive name for the codec, meant to be more human readable than name.
2785 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
2786 */
2787 const char *long_name;
2788 enum AVMediaType type;
2789 enum AVCodecID id;
2790 /**
2791 * Codec capabilities.
2792 * see CODEC_CAP_*
2793 */
2794 int capabilities;
2795 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
2796 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
2797 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
2798 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
2799 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
2800 #if FF_API_LOWRES
2801 attribute_deprecated uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
2802 #endif
2803 const AVClass *priv_class; ///< AVClass for the private context
2804 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
2805
2806 /*****************************************************************
2807 * No fields below this line are part of the public API. They
2808 * may not be used outside of libavcodec and can be changed and
2809 * removed at will.
2810 * New public fields should be added right above.
2811 *****************************************************************
2812 */
2813 int priv_data_size;
2814 struct AVCodec *next;
2815 /**
2816 * @name Frame-level threading support functions
2817 * @{
2818 */
2819 /**
2820 * If defined, called on thread contexts when they are created.
2821 * If the codec allocates writable tables in init(), re-allocate them here.
2822 * priv_data will be set to a copy of the original.
2823 */
2824 int (*init_thread_copy)(AVCodecContext *);
2825 /**
2826 * Copy necessary context variables from a previous thread context to the current one.
2827 * If not defined, the next thread will start automatically; otherwise, the codec
2828 * must call ff_thread_finish_setup().
2829 *
2830 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
2831 */
2832 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
2833 /** @} */
2834
2835 /**
2836 * Private codec-specific defaults.
2837 */
2838 const AVCodecDefault *defaults;
2839
2840 /**
2841 * Initialize codec static data, called from avcodec_register().
2842 */
2843 void (*init_static_data)(struct AVCodec *codec);
2844
2845 int (*init)(AVCodecContext *);
2846 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
2847 const struct AVSubtitle *sub);
2848 /**
2849 * Encode data to an AVPacket.
2850 *
2851 * @param avctx codec context
2852 * @param avpkt output AVPacket (may contain a user-provided buffer)
2853 * @param[in] frame AVFrame containing the raw data to be encoded
2854 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
2855 * non-empty packet was returned in avpkt.
2856 * @return 0 on success, negative error code on failure
2857 */
2858 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
2859 int *got_packet_ptr);
2860 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
2861 int (*close)(AVCodecContext *);
2862 /**
2863 * Flush buffers.
2864 * Will be called when seeking
2865 */
2866 void (*flush)(AVCodecContext *);
2867 } AVCodec;
2868
2869 /**
2870 * AVHWAccel.
2871 */
2872 typedef struct AVHWAccel {
2873 /**
2874 * Name of the hardware accelerated codec.
2875 * The name is globally unique among encoders and among decoders (but an
2876 * encoder and a decoder can share the same name).
2877 */
2878 const char *name;
2879
2880 /**
2881 * Type of codec implemented by the hardware accelerator.
2882 *
2883 * See AVMEDIA_TYPE_xxx
2884 */
2885 enum AVMediaType type;
2886
2887 /**
2888 * Codec implemented by the hardware accelerator.
2889 *
2890 * See AV_CODEC_ID_xxx
2891 */
2892 enum AVCodecID id;
2893
2894 /**
2895 * Supported pixel format.
2896 *
2897 * Only hardware accelerated formats are supported here.
2898 */
2899 enum AVPixelFormat pix_fmt;
2900
2901 /**
2902 * Hardware accelerated codec capabilities.
2903 * see FF_HWACCEL_CODEC_CAP_*
2904 */
2905 int capabilities;
2906
2907 /*****************************************************************
2908 * No fields below this line are part of the public API. They
2909 * may not be used outside of libavcodec and can be changed and
2910 * removed at will.
2911 * New public fields should be added right above.
2912 *****************************************************************
2913 */
2914 struct AVHWAccel *next;
2915
2916 /**
2917 * Allocate a custom buffer
2918 */
2919 int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
2920
2921 /**
2922 * Called at the beginning of each frame or field picture.
2923 *
2924 * Meaningful frame information (codec specific) is guaranteed to
2925 * be parsed at this point. This function is mandatory.
2926 *
2927 * Note that buf can be NULL along with buf_size set to 0.
2928 * Otherwise, this means the whole frame is available at this point.
2929 *
2930 * @param avctx the codec context
2931 * @param buf the frame data buffer base
2932 * @param buf_size the size of the frame in bytes
2933 * @return zero if successful, a negative value otherwise
2934 */
2935 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2936
2937 /**
2938 * Callback for each slice.
2939 *
2940 * Meaningful slice information (codec specific) is guaranteed to
2941 * be parsed at this point. This function is mandatory.
2942 *
2943 * @param avctx the codec context
2944 * @param buf the slice data buffer base
2945 * @param buf_size the size of the slice in bytes
2946 * @return zero if successful, a negative value otherwise
2947 */
2948 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
2949
2950 /**
2951 * Called at the end of each frame or field picture.
2952 *
2953 * The whole picture is parsed at this point and can now be sent
2954 * to the hardware accelerator. This function is mandatory.
2955 *
2956 * @param avctx the codec context
2957 * @return zero if successful, a negative value otherwise
2958 */
2959 int (*end_frame)(AVCodecContext *avctx);
2960
2961 /**
2962 * Size of per-frame hardware accelerator private data.
2963 *
2964 * Private data is allocated with av_mallocz() before
2965 * AVCodecContext.get_buffer() and deallocated after
2966 * AVCodecContext.release_buffer().
2967 */
2968 int frame_priv_data_size;
2969
2970 /**
2971 * Initialize the hwaccel private data.
2972 *
2973 * This will be called from ff_get_format(), after hwaccel and
2974 * hwaccel_context are set and the hwaccel private data in AVCodecInternal
2975 * is allocated.
2976 */
2977 int (*init)(AVCodecContext *avctx);
2978
2979 /**
2980 * Uninitialize the hwaccel private data.
2981 *
2982 * This will be called from get_format() or avcodec_close(), after hwaccel
2983 * and hwaccel_context are already uninitialized.
2984 */
2985 int (*uninit)(AVCodecContext *avctx);
2986
2987 /**
2988 * Size of the private data to allocate in
2989 * AVCodecInternal.hwaccel_priv_data.
2990 */
2991 int priv_data_size;
2992 } AVHWAccel;
2993
2994 /**
2995 * @defgroup lavc_picture AVPicture
2996 *
2997 * Functions for working with AVPicture
2998 * @{
2999 */
3000
3001 /**
3002 * four components are given, that's all.
3003 * the last component is alpha
3004 */
3005 typedef struct AVPicture {
3006 uint8_t *data[AV_NUM_DATA_POINTERS];
3007 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3008 } AVPicture;
3009
3010 /**
3011 * @}
3012 */
3013
3014 #define AVPALETTE_SIZE 1024
3015 #define AVPALETTE_COUNT 256
3016
3017 enum AVSubtitleType {
3018 SUBTITLE_NONE,
3019
3020 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3021
3022 /**
3023 * Plain text, the text field must be set by the decoder and is
3024 * authoritative. ass and pict fields may contain approximations.
3025 */
3026 SUBTITLE_TEXT,
3027
3028 /**
3029 * Formatted text, the ass field must be set by the decoder and is
3030 * authoritative. pict and text fields may contain approximations.
3031 */
3032 SUBTITLE_ASS,
3033 };
3034
3035 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3036
3037 typedef struct AVSubtitleRect {
3038 int x; ///< top left corner of pict, undefined when pict is not set
3039 int y; ///< top left corner of pict, undefined when pict is not set
3040 int w; ///< width of pict, undefined when pict is not set
3041 int h; ///< height of pict, undefined when pict is not set
3042 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3043
3044 /**
3045 * data+linesize for the bitmap of this subtitle.
3046 * can be set for text/ass as well once they where rendered
3047 */
3048 AVPicture pict;
3049 enum AVSubtitleType type;
3050
3051 char *text; ///< 0 terminated plain UTF-8 text
3052
3053 /**
3054 * 0 terminated ASS/SSA compatible event line.
3055 * The pressentation of this is unaffected by the other values in this
3056 * struct.
3057 */
3058 char *ass;
3059 int flags;
3060 } AVSubtitleRect;
3061
3062 typedef struct AVSubtitle {
3063 uint16_t format; /* 0 = graphics */
3064 uint32_t start_display_time; /* relative to packet pts, in ms */
3065 uint32_t end_display_time; /* relative to packet pts, in ms */
3066 unsigned num_rects;
3067 AVSubtitleRect **rects;
3068 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3069 } AVSubtitle;
3070
3071 /**
3072 * If c is NULL, returns the first registered codec,
3073 * if c is non-NULL, returns the next registered codec after c,
3074 * or NULL if c is the last one.
3075 */
3076 AVCodec *av_codec_next(const AVCodec *c);
3077
3078 /**
3079 * Return the LIBAVCODEC_VERSION_INT constant.
3080 */
3081 unsigned avcodec_version(void);
3082
3083 /**
3084 * Return the libavcodec build-time configuration.
3085 */
3086 const char *avcodec_configuration(void);
3087
3088 /**
3089 * Return the libavcodec license.
3090 */
3091 const char *avcodec_license(void);
3092
3093 /**
3094 * Register the codec codec and initialize libavcodec.
3095 *
3096 * @warning either this function or avcodec_register_all() must be called
3097 * before any other libavcodec functions.
3098 *
3099 * @see avcodec_register_all()
3100 */
3101 void avcodec_register(AVCodec *codec);
3102
3103 /**
3104 * Register all the codecs, parsers and bitstream filters which were enabled at
3105 * configuration time. If you do not call this function you can select exactly
3106 * which formats you want to support, by using the individual registration
3107 * functions.
3108 *
3109 * @see avcodec_register
3110 * @see av_register_codec_parser
3111 * @see av_register_bitstream_filter
3112 */
3113 void avcodec_register_all(void);
3114
3115 /**
3116 * Allocate an AVCodecContext and set its fields to default values. The
3117 * resulting struct should be freed with avcodec_free_context().
3118 *
3119 * @param codec if non-NULL, allocate private data and initialize defaults
3120 * for the given codec. It is illegal to then call avcodec_open2()
3121 * with a different codec.
3122 * If NULL, then the codec-specific defaults won't be initialized,
3123 * which may result in suboptimal default settings (this is
3124 * important mainly for encoders, e.g. libx264).
3125 *
3126 * @return An AVCodecContext filled with default values or NULL on failure.
3127 * @see avcodec_get_context_defaults
3128 */
3129 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3130
3131 /**
3132 * Free the codec context and everything associated with it and write NULL to
3133 * the provided pointer.
3134 */
3135 void avcodec_free_context(AVCodecContext **avctx);
3136
3137 /**
3138 * Set the fields of the given AVCodecContext to default values corresponding
3139 * to the given codec (defaults may be codec-dependent).
3140 *
3141 * Do not call this function if a non-NULL codec has been passed
3142 * to avcodec_alloc_context3() that allocated this AVCodecContext.
3143 * If codec is non-NULL, it is illegal to call avcodec_open2() with a
3144 * different codec on this AVCodecContext.
3145 */
3146 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3147
3148 /**
3149 * Get the AVClass for AVCodecContext. It can be used in combination with
3150 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3151 *
3152 * @see av_opt_find().
3153 */
3154 const AVClass *avcodec_get_class(void);
3155
3156 /**
3157 * Copy the settings of the source AVCodecContext into the destination
3158 * AVCodecContext. The resulting destination codec context will be
3159 * unopened, i.e. you are required to call avcodec_open2() before you
3160 * can use this AVCodecContext to decode/encode video/audio data.
3161 *
3162 * @param dest target codec context, should be initialized with
3163 * avcodec_alloc_context3(), but otherwise uninitialized
3164 * @param src source codec context
3165 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3166 */
3167 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3168
3169 #if FF_API_AVFRAME_LAVC
3170 /**
3171 * @deprecated use av_frame_alloc()
3172 */
3173 attribute_deprecated
3174 AVFrame *avcodec_alloc_frame(void);
3175
3176 /**
3177 * Set the fields of the given AVFrame to default values.
3178 *
3179 * @param frame The AVFrame of which the fields should be set to default values.
3180 *
3181 * @deprecated use av_frame_unref()
3182 */
3183 attribute_deprecated
3184 void avcodec_get_frame_defaults(AVFrame *frame);
3185
3186 /**
3187 * Free the frame and any dynamically allocated objects in it,
3188 * e.g. extended_data.
3189 *
3190 * @param frame frame to be freed. The pointer will be set to NULL.
3191 *
3192 * @warning this function does NOT free the data buffers themselves
3193 * (it does not know how, since they might have been allocated with
3194 * a custom get_buffer()).
3195 *
3196 * @deprecated use av_frame_free()
3197 */
3198 attribute_deprecated
3199 void avcodec_free_frame(AVFrame **frame);
3200 #endif
3201
3202 /**
3203 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3204 * function the context has to be allocated with avcodec_alloc_context3().
3205 *
3206 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3207 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3208 * retrieving a codec.
3209 *
3210 * @warning This function is not thread safe!
3211 *
3212 * @code
3213 * avcodec_register_all();
3214 * av_dict_set(&opts, "b", "2.5M", 0);
3215 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3216 * if (!codec)
3217 * exit(1);
3218 *
3219 * context = avcodec_alloc_context3(codec);
3220 *
3221 * if (avcodec_open2(context, codec, opts) < 0)
3222 * exit(1);
3223 * @endcode
3224 *
3225 * @param avctx The context to initialize.
3226 * @param codec The codec to open this context for. If a non-NULL codec has been
3227 * previously passed to avcodec_alloc_context3() or
3228 * avcodec_get_context_defaults3() for this context, then this
3229 * parameter MUST be either NULL or equal to the previously passed
3230 * codec.
3231 * @param options A dictionary filled with AVCodecContext and codec-private options.
3232 * On return this object will be filled with options that were not found.
3233 *
3234 * @return zero on success, a negative value on error
3235 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3236 * av_dict_set(), av_opt_find().
3237 */
3238 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3239
3240 /**
3241 * Close a given AVCodecContext and free all the data associated with it
3242 * (but not the AVCodecContext itself).
3243 *
3244 * Calling this function on an AVCodecContext that hasn't been opened will free
3245 * the codec-specific data allocated in avcodec_alloc_context3() /
3246 * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
3247 * do nothing.
3248 */
3249 int avcodec_close(AVCodecContext *avctx);
3250
3251 /**
3252 * Free all allocated data in the given subtitle struct.
3253 *
3254 * @param sub AVSubtitle to free.
3255 */
3256 void avsubtitle_free(AVSubtitle *sub);
3257
3258 /**
3259 * @}
3260 */
3261
3262 /**
3263 * @addtogroup lavc_packet
3264 * @{
3265 */
3266
3267 #if FF_API_DESTRUCT_PACKET
3268 /**
3269 * Default packet destructor.
3270 * @deprecated use the AVBuffer API instead
3271 */
3272 attribute_deprecated
3273 void av_destruct_packet(AVPacket *pkt);
3274 #endif
3275
3276 /**
3277 * Initialize optional fields of a packet with default values.
3278 *
3279 * Note, this does not touch the data and size members, which have to be
3280 * initialized separately.
3281 *
3282 * @param pkt packet
3283 */
3284 void av_init_packet(AVPacket *pkt);
3285
3286 /**
3287 * Allocate the payload of a packet and initialize its fields with
3288 * default values.
3289 *
3290 * @param pkt packet
3291 * @param size wanted payload size
3292 * @return 0 if OK, AVERROR_xxx otherwise
3293 */
3294 int av_new_packet(AVPacket *pkt, int size);
3295
3296 /**
3297 * Reduce packet size, correctly zeroing padding
3298 *
3299 * @param pkt packet
3300 * @param size new size
3301 */
3302 void av_shrink_packet(AVPacket *pkt, int size);
3303
3304 /**
3305 * Increase packet size, correctly zeroing padding
3306 *
3307 * @param pkt packet
3308 * @param grow_by number of bytes by which to increase the size of the packet
3309 */
3310 int av_grow_packet(AVPacket *pkt, int grow_by);
3311
3312 /**
3313 * Initialize a reference-counted packet from av_malloc()ed data.
3314 *
3315 * @param pkt packet to be initialized. This function will set the data, size,
3316 * buf and destruct fields, all others are left untouched.
3317 * @param data Data allocated by av_malloc() to be used as packet data. If this
3318 * function returns successfully, the data is owned by the underlying AVBuffer.
3319 * The caller may not access the data through other means.
3320 * @param size size of data in bytes, without the padding. I.e. the full buffer
3321 * size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
3322 *
3323 * @return 0 on success, a negative AVERROR on error
3324 */
3325 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
3326
3327 /**
3328 * @warning This is a hack - the packet memory allocation stuff is broken. The
3329 * packet is allocated if it was not really allocated.
3330 */
3331 int av_dup_packet(AVPacket *pkt);
3332
3333 /**
3334 * Free a packet.
3335 *
3336 * @param pkt packet to free
3337 */
3338 void av_free_packet(AVPacket *pkt);
3339
3340 /**
3341 * Allocate new information of a packet.
3342 *
3343 * @param pkt packet
3344 * @param type side information type
3345 * @param size side information size
3346 * @return pointer to fresh allocated data or NULL otherwise
3347 */
3348 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3349 int size);
3350
3351 /**
3352 * Shrink the already allocated side data buffer
3353 *
3354 * @param pkt packet
3355 * @param type side information type
3356 * @param size new side information size
3357 * @return 0 on success, < 0 on failure
3358 */
3359 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3360 int size);
3361
3362 /**
3363 * Get side information from packet.
3364 *
3365 * @param pkt packet
3366 * @param type desired side information type
3367 * @param size pointer for side information size to store (optional)
3368 * @return pointer to data if present or NULL otherwise
3369 */
3370 uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3371 int *size);
3372
3373 /**
3374 * Convenience function to free all the side data stored.
3375 * All the other fields stay untouched.
3376 *
3377 * @param pkt packet
3378 */
3379 void av_packet_free_side_data(AVPacket *pkt);
3380
3381 /**
3382 * Setup a new reference to the data described by a given packet
3383 *
3384 * If src is reference-counted, setup dst as a new reference to the
3385 * buffer in src. Otherwise allocate a new buffer in dst and copy the
3386 * data from src into it.
3387 *
3388 * All the other fields are copied from src.
3389 *
3390 * @see av_packet_unref
3391 *
3392 * @param dst Destination packet
3393 * @param src Source packet
3394 *
3395 * @return 0 on success, a negative AVERROR on error.
3396 */
3397 int av_packet_ref(AVPacket *dst, AVPacket *src);
3398
3399 /**
3400 * Wipe the packet.
3401 *
3402 * Unreference the buffer referenced by the packet and reset the
3403 * remaining packet fields to their default values.
3404 *
3405 * @param pkt The packet to be unreferenced.
3406 */
3407 void av_packet_unref(AVPacket *pkt);
3408
3409 /**
3410 * Move every field in src to dst and reset src.
3411 *
3412 * @see av_packet_unref
3413 *
3414 * @param src Source packet, will be reset
3415 * @param dst Destination packet
3416 */
3417 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
3418
3419 /**
3420 * Copy only "properties" fields from src to dst.
3421 *
3422 * Properties for the purpose of this function are all the fields
3423 * beside those related to the packet data (buf, data, size)
3424 *
3425 * @param dst Destination packet
3426 * @param src Source packet
3427 *
3428 * @return 0 on success AVERROR on failure.
3429 *
3430 */
3431 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
3432
3433 /**
3434 * Convert valid timing fields (timestamps / durations) in a packet from one
3435 * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
3436 * ignored.
3437 *
3438 * @param pkt packet on which the conversion will be performed
3439 * @param tb_src source timebase, in which the timing fields in pkt are
3440 * expressed
3441 * @param tb_dst destination timebase, to which the timing fields will be
3442 * converted
3443 */
3444 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
3445
3446 /**
3447 * @}
3448 */
3449
3450 /**
3451 * @addtogroup lavc_decoding
3452 * @{
3453 */
3454
3455 /**
3456 * Find a registered decoder with a matching codec ID.
3457 *
3458 * @param id AVCodecID of the requested decoder
3459 * @return A decoder if one was found, NULL otherwise.
3460 */
3461 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3462
3463 /**
3464 * Find a registered decoder with the specified name.
3465 *
3466 * @param name name of the requested decoder
3467 * @return A decoder if one was found, NULL otherwise.
3468 */
3469 AVCodec *avcodec_find_decoder_by_name(const char *name);
3470
3471 #if FF_API_GET_BUFFER
3472 attribute_deprecated int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
3473 attribute_deprecated void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
3474 attribute_deprecated int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
3475 #endif
3476
3477 /**
3478 * The default callback for AVCodecContext.get_buffer2(). It is made public so
3479 * it can be called by custom get_buffer2() implementations for decoders without
3480 * CODEC_CAP_DR1 set.
3481 */
3482 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
3483
3484 #if FF_API_EMU_EDGE
3485 /**
3486 * Return the amount of padding in pixels which the get_buffer callback must
3487 * provide around the edge of the image for codecs which do not have the
3488 * CODEC_FLAG_EMU_EDGE flag.
3489 *
3490 * @return Required padding in pixels.
3491 *
3492 * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
3493 * needed
3494 */
3495 attribute_deprecated
3496 unsigned avcodec_get_edge_width(void);
3497 #endif
3498
3499 /**
3500 * Modify width and height values so that they will result in a memory
3501 * buffer that is acceptable for the codec if you do not use any horizontal
3502 * padding.
3503 *
3504 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3505 */
3506 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3507
3508 /**
3509 * Modify width and height values so that they will result in a memory
3510 * buffer that is acceptable for the codec if you also ensure that all
3511 * line sizes are a multiple of the respective linesize_align[i].
3512 *
3513 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3514 */
3515 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3516 int linesize_align[AV_NUM_DATA_POINTERS]);
3517
3518 /**
3519 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3520 *
3521 * Some decoders may support multiple frames in a single AVPacket. Such
3522 * decoders would then just decode the first frame and the return value would be
3523 * less than the packet size. In this case, avcodec_decode_audio4 has to be
3524 * called again with an AVPacket containing the remaining data in order to
3525 * decode the second frame, etc... Even if no frames are returned, the packet
3526 * needs to be fed to the decoder with remaining data until it is completely
3527 * consumed or an error occurs.
3528 *
3529 * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
3530 * and output. This means that for some packets they will not immediately
3531 * produce decoded output and need to be flushed at the end of decoding to get
3532 * all the decoded data. Flushing is done by calling this function with packets
3533 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3534 * returning samples. It is safe to flush even those decoders that are not
3535 * marked with CODEC_CAP_DELAY, then no samples will be returned.
3536 *
3537 * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
3538 * larger than the actual read bytes because some optimized bitstream
3539 * readers read 32 or 64 bits at once and could read over the end.
3540 *
3541 * @param avctx the codec context
3542 * @param[out] frame The AVFrame in which to store decoded audio samples.
3543 * The decoder will allocate a buffer for the decoded frame by
3544 * calling the AVCodecContext.get_buffer2() callback.
3545 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3546 * reference counted and the returned reference belongs to the
3547 * caller. The caller must release the frame using av_frame_unref()
3548 * when the frame is no longer needed. The caller may safely write
3549 * to the frame if av_frame_is_writable() returns 1.
3550 * When AVCodecContext.refcounted_frames is set to 0, the returned
3551 * reference belongs to the decoder and is valid only until the
3552 * next call to this function or until closing or flushing the
3553 * decoder. The caller may not write to it.
3554 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3555 * non-zero. Note that this field being set to zero
3556 * does not mean that an error has occurred. For
3557 * decoders with CODEC_CAP_DELAY set, no given decode
3558 * call is guaranteed to produce a frame.
3559 * @param[in] avpkt The input AVPacket containing the input buffer.
3560 * At least avpkt->data and avpkt->size should be set. Some
3561 * decoders might also require additional fields to be set.
3562 * @return A negative error code is returned if an error occurred during
3563 * decoding, otherwise the number of bytes consumed from the input
3564 * AVPacket is returned.
3565 */
3566 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3567 int *got_frame_ptr, AVPacket *avpkt);
3568
3569 /**
3570 * Decode the video frame of size avpkt->size from avpkt->data into picture.
3571 * Some decoders may support multiple frames in a single AVPacket, such
3572 * decoders would then just decode the first frame.
3573 *
3574 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3575 * the actual read bytes because some optimized bitstream readers read 32 or 64
3576 * bits at once and could read over the end.
3577 *
3578 * @warning The end of the input buffer buf should be set to 0 to ensure that
3579 * no overreading happens for damaged MPEG streams.
3580 *
3581 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3582 * between input and output, these need to be fed with avpkt->data=NULL,
3583 * avpkt->size=0 at the end to return the remaining frames.
3584 *
3585 * @param avctx the codec context
3586 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3587 * Use av_frame_alloc() to get an AVFrame. The codec will
3588 * allocate memory for the actual bitmap by calling the
3589 * AVCodecContext.get_buffer2() callback.
3590 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3591 * reference counted and the returned reference belongs to the
3592 * caller. The caller must release the frame using av_frame_unref()
3593 * when the frame is no longer needed. The caller may safely write
3594 * to the frame if av_frame_is_writable() returns 1.
3595 * When AVCodecContext.refcounted_frames is set to 0, the returned
3596 * reference belongs to the decoder and is valid only until the
3597 * next call to this function or until closing or flushing the
3598 * decoder. The caller may not write to it.
3599 *
3600 * @param[in] avpkt The input AVpacket containing the input buffer.
3601 * You can create such packet with av_init_packet() and by then setting
3602 * data and size, some decoders might in addition need other fields like
3603 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3604 * fields possible.
3605 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3606 * @return On error a negative value is returned, otherwise the number of bytes
3607 * used or zero if no frame could be decompressed.
3608 */
3609 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3610 int *got_picture_ptr,
3611 AVPacket *avpkt);
3612
3613 /**
3614 * Decode a subtitle message.
3615 * Return a negative value on error, otherwise return the number of bytes used.
3616 * If no subtitle could be decompressed, got_sub_ptr is zero.
3617 * Otherwise, the subtitle is stored in *sub.
3618 * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3619 * simplicity, because the performance difference is expect to be negligible
3620 * and reusing a get_buffer written for video codecs would probably perform badly
3621 * due to a potentially very different allocation pattern.
3622 *
3623 * @param avctx the codec context
3624 * @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
3625 freed with avsubtitle_free if *got_sub_ptr is set.
3626 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3627 * @param[in] avpkt The input AVPacket containing the input buffer.
3628 */
3629 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3630 int *got_sub_ptr,
3631 AVPacket *avpkt);
3632
3633 /**
3634 * @defgroup lavc_parsing Frame parsing
3635 * @{
3636 */
3637
3638 enum AVPictureStructure {
3639 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
3640 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
3641 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
3642 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
3643 };
3644
3645 typedef struct AVCodecParserContext {
3646 void *priv_data;
3647 struct AVCodecParser *parser;
3648 int64_t frame_offset; /* offset of the current frame */
3649 int64_t cur_offset; /* current offset
3650 (incremented by each av_parser_parse()) */
3651 int64_t next_frame_offset; /* offset of the next frame */
3652 /* video info */
3653 int pict_type; /* XXX: Put it back in AVCodecContext. */
3654 /**
3655 * This field is used for proper frame duration computation in lavf.
3656 * It signals, how much longer the frame duration of the current frame
3657 * is compared to normal frame duration.
3658 *
3659 * frame_duration = (1 + repeat_pict) * time_base
3660 *
3661 * It is used by codecs like H.264 to display telecined material.
3662 */
3663 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3664 int64_t pts; /* pts of the current frame */
3665 int64_t dts; /* dts of the current frame */
3666
3667 /* private data */
3668 int64_t last_pts;
3669 int64_t last_dts;
3670 int fetch_timestamp;
3671
3672 #define AV_PARSER_PTS_NB 4
3673 int cur_frame_start_index;
3674 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3675 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3676 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
3677
3678 int flags;
3679 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
3680 #define PARSER_FLAG_ONCE 0x0002
3681 /// Set if the parser has a valid file offset
3682 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
3683
3684 int64_t offset; ///< byte offset from starting packet start
3685 int64_t cur_frame_end[AV_PARSER_PTS_NB];
3686
3687 /**
3688 * Set by parser to 1 for key frames and 0 for non-key frames.
3689 * It is initialized to -1, so if the parser doesn't set this flag,
3690 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
3691 * will be used.
3692 */
3693 int key_frame;
3694
3695 /**
3696 * Time difference in stream time base units from the pts of this
3697 * packet to the point at which the output from the decoder has converged
3698 * independent from the availability of previous frames. That is, the
3699 * frames are virtually identical no matter if decoding started from
3700 * the very first frame or from this keyframe.
3701 * Is AV_NOPTS_VALUE if unknown.
3702 * This field is not the display duration of the current frame.
3703 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
3704 * set.
3705 *
3706 * The purpose of this field is to allow seeking in streams that have no
3707 * keyframes in the conventional sense. It corresponds to the
3708 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
3709 * essential for some types of subtitle streams to ensure that all
3710 * subtitles are correctly displayed after seeking.
3711 */
3712 int64_t convergence_duration;
3713
3714 // Timestamp generation support:
3715 /**
3716 * Synchronization point for start of timestamp generation.
3717 *
3718 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
3719 * (default).
3720 *
3721 * For example, this corresponds to presence of H.264 buffering period
3722 * SEI message.
3723 */
3724 int dts_sync_point;
3725
3726 /**
3727 * Offset of the current timestamp against last timestamp sync point in
3728 * units of AVCodecContext.time_base.
3729 *
3730 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3731 * contain a valid timestamp offset.
3732 *
3733 * Note that the timestamp of sync point has usually a nonzero
3734 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
3735 * the next frame after timestamp sync point will be usually 1.
3736 *
3737 * For example, this corresponds to H.264 cpb_removal_delay.
3738 */
3739 int dts_ref_dts_delta;
3740
3741 /**
3742 * Presentation delay of current frame in units of AVCodecContext.time_base.
3743 *
3744 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
3745 * contain valid non-negative timestamp delta (presentation time of a frame
3746 * must not lie in the past).
3747 *
3748 * This delay represents the difference between decoding and presentation
3749 * time of the frame.
3750 *
3751 * For example, this corresponds to H.264 dpb_output_delay.
3752 */
3753 int pts_dts_delta;
3754
3755 /**
3756 * Position of the packet in file.
3757 *
3758 * Analogous to cur_frame_pts/dts
3759 */
3760 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
3761
3762 /**
3763 * Byte position of currently parsed frame in stream.
3764 */
3765 int64_t pos;
3766
3767 /**
3768 * Previous frame byte position.
3769 */
3770 int64_t last_pos;
3771
3772 /**
3773 * Duration of the current frame.
3774 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
3775 * For all other types, this is in units of AVCodecContext.time_base.
3776 */
3777 int duration;
3778
3779 enum AVFieldOrder field_order;
3780
3781 /**
3782 * Indicate whether a picture is coded as a frame, top field or bottom field.
3783 *
3784 * For example, H.264 field_pic_flag equal to 0 corresponds to
3785 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
3786 * equal to 1 and bottom_field_flag equal to 0 corresponds to
3787 * AV_PICTURE_STRUCTURE_TOP_FIELD.
3788 */
3789 enum AVPictureStructure picture_structure;
3790
3791 /**
3792 * Picture number incremented in presentation or output order.
3793 * This field may be reinitialized at the first picture of a new sequence.
3794 *
3795 * For example, this corresponds to H.264 PicOrderCnt.
3796 */
3797 int output_picture_number;
3798 } AVCodecParserContext;
3799
3800 typedef struct AVCodecParser {
3801 int codec_ids[5]; /* several codec IDs are permitted */
3802 int priv_data_size;
3803 int (*parser_init)(AVCodecParserContext *s);
3804 int (*parser_parse)(AVCodecParserContext *s,
3805 AVCodecContext *avctx,
3806 const uint8_t **poutbuf, int *poutbuf_size,
3807 const uint8_t *buf, int buf_size);
3808 void (*parser_close)(AVCodecParserContext *s);
3809 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
3810 struct AVCodecParser *next;
3811 } AVCodecParser;
3812
3813 AVCodecParser *av_parser_next(const AVCodecParser *c);
3814
3815 void av_register_codec_parser(AVCodecParser *parser);
3816 AVCodecParserContext *av_parser_init(int codec_id);
3817
3818 /**
3819 * Parse a packet.
3820 *
3821 * @param s parser context.
3822 * @param avctx codec context.
3823 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
3824 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
3825 * @param buf input buffer.
3826 * @param buf_size input length, to signal EOF, this should be 0 (so that the last frame can be output).
3827 * @param pts input presentation timestamp.
3828 * @param dts input decoding timestamp.
3829 * @param pos input byte position in stream.
3830 * @return the number of bytes of the input bitstream used.
3831 *
3832 * Example:
3833 * @code
3834 * while(in_len){
3835 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
3836 * in_data, in_len,
3837 * pts, dts, pos);
3838 * in_data += len;
3839 * in_len -= len;
3840 *
3841 * if(size)
3842 * decode_frame(data, size);
3843 * }
3844 * @endcode
3845 */
3846 int av_parser_parse2(AVCodecParserContext *s,
3847 AVCodecContext *avctx,
3848 uint8_t **poutbuf, int *poutbuf_size,
3849 const uint8_t *buf, int buf_size,
3850 int64_t pts, int64_t dts,
3851 int64_t pos);
3852
3853 /**
3854 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
3855 * @deprecated use AVBitstreamFilter
3856 */
3857 int av_parser_change(AVCodecParserContext *s,
3858 AVCodecContext *avctx,
3859 uint8_t **poutbuf, int *poutbuf_size,
3860 const uint8_t *buf, int buf_size, int keyframe);
3861 void av_parser_close(AVCodecParserContext *s);
3862
3863 /**
3864 * @}
3865 * @}
3866 */
3867
3868 /**
3869 * @addtogroup lavc_encoding
3870 * @{
3871 */
3872
3873 /**
3874 * Find a registered encoder with a matching codec ID.
3875 *
3876 * @param id AVCodecID of the requested encoder
3877 * @return An encoder if one was found, NULL otherwise.
3878 */
3879 AVCodec *avcodec_find_encoder(enum AVCodecID id);
3880
3881 /**
3882 * Find a registered encoder with the specified name.
3883 *
3884 * @param name name of the requested encoder
3885 * @return An encoder if one was found, NULL otherwise.
3886 */
3887 AVCodec *avcodec_find_encoder_by_name(const char *name);
3888
3889 /**
3890 * Encode a frame of audio.
3891 *
3892 * Takes input samples from frame and writes the next output packet, if
3893 * available, to avpkt. The output packet does not necessarily contain data for
3894 * the most recent frame, as encoders can delay, split, and combine input frames
3895 * internally as needed.
3896 *
3897 * @param avctx codec context
3898 * @param avpkt output AVPacket.
3899 * The user can supply an output buffer by setting
3900 * avpkt->data and avpkt->size prior to calling the
3901 * function, but if the size of the user-provided data is not
3902 * large enough, encoding will fail. All other AVPacket fields
3903 * will be reset by the encoder using av_init_packet(). If
3904 * avpkt->data is NULL, the encoder will allocate it.
3905 * The encoder will set avpkt->size to the size of the
3906 * output packet.
3907 *
3908 * If this function fails or produces no output, avpkt will be
3909 * freed using av_free_packet() (i.e. avpkt->destruct will be
3910 * called to free the user supplied buffer).
3911 * @param[in] frame AVFrame containing the raw audio data to be encoded.
3912 * May be NULL when flushing an encoder that has the
3913 * CODEC_CAP_DELAY capability set.
3914 * If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
3915 * can have any number of samples.
3916 * If it is not set, frame->nb_samples must be equal to
3917 * avctx->frame_size for all frames except the last.
3918 * The final frame may be smaller than avctx->frame_size.
3919 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3920 * output packet is non-empty, and to 0 if it is
3921 * empty. If the function returns an error, the
3922 * packet can be assumed to be invalid, and the
3923 * value of got_packet_ptr is undefined and should
3924 * not be used.
3925 * @return 0 on success, negative error code on failure
3926 */
3927 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
3928 const AVFrame *frame, int *got_packet_ptr);
3929
3930 /**
3931 * Encode a frame of video.
3932 *
3933 * Takes input raw video data from frame and writes the next output packet, if
3934 * available, to avpkt. The output packet does not necessarily contain data for
3935 * the most recent frame, as encoders can delay and reorder input frames
3936 * internally as needed.
3937 *
3938 * @param avctx codec context
3939 * @param avpkt output AVPacket.
3940 * The user can supply an output buffer by setting
3941 * avpkt->data and avpkt->size prior to calling the
3942 * function, but if the size of the user-provided data is not
3943 * large enough, encoding will fail. All other AVPacket fields
3944 * will be reset by the encoder using av_init_packet(). If
3945 * avpkt->data is NULL, the encoder will allocate it.
3946 * The encoder will set avpkt->size to the size of the
3947 * output packet. The returned data (if any) belongs to the
3948 * caller, he is responsible for freeing it.
3949 *
3950 * If this function fails or produces no output, avpkt will be
3951 * freed using av_free_packet() (i.e. avpkt->destruct will be
3952 * called to free the user supplied buffer).
3953 * @param[in] frame AVFrame containing the raw video data to be encoded.
3954 * May be NULL when flushing an encoder that has the
3955 * CODEC_CAP_DELAY capability set.
3956 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
3957 * output packet is non-empty, and to 0 if it is
3958 * empty. If the function returns an error, the
3959 * packet can be assumed to be invalid, and the
3960 * value of got_packet_ptr is undefined and should
3961 * not be used.
3962 * @return 0 on success, negative error code on failure
3963 */
3964 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
3965 const AVFrame *frame, int *got_packet_ptr);
3966
3967 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
3968 const AVSubtitle *sub);
3969
3970
3971 /**
3972 * @}
3973 */
3974
3975 /**
3976 * @addtogroup lavc_picture
3977 * @{
3978 */
3979
3980 /**
3981 * Allocate memory for a picture. Call avpicture_free() to free it.
3982 *
3983 * @see avpicture_fill()
3984 *
3985 * @param picture the picture to be filled in
3986 * @param pix_fmt the format of the picture
3987 * @param width the width of the picture
3988 * @param height the height of the picture
3989 * @return zero if successful, a negative value if not
3990 */
3991 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
3992
3993 /**
3994 * Free a picture previously allocated by avpicture_alloc().
3995 * The data buffer used by the AVPicture is freed, but the AVPicture structure
3996 * itself is not.
3997 *
3998 * @param picture the AVPicture to be freed
3999 */
4000 void avpicture_free(AVPicture *picture);
4001
4002 /**
4003 * Fill in the AVPicture fields.
4004 * The fields of the given AVPicture are filled in by using the 'ptr' address
4005 * which points to the image data buffer. Depending on the specified picture
4006 * format, one or multiple image data pointers and line sizes will be set.
4007 * If a planar format is specified, several pointers will be set pointing to
4008 * the different picture planes and the line sizes of the different planes
4009 * will be stored in the lines_sizes array.
4010 * Call with ptr == NULL to get the required size for the ptr buffer.
4011 *
4012 * To allocate the buffer and fill in the AVPicture fields in one call,
4013 * use avpicture_alloc().
4014 *
4015 * @param picture AVPicture whose fields are to be filled in
4016 * @param ptr Buffer which will contain or contains the actual image data
4017 * @param pix_fmt The format in which the picture data is stored.
4018 * @param width the width of the image in pixels
4019 * @param height the height of the image in pixels
4020 * @return size of the image data in bytes
4021 */
4022 int avpicture_fill(AVPicture *picture, uint8_t *ptr,
4023 enum AVPixelFormat pix_fmt, int width, int height);
4024
4025 /**
4026 * Copy pixel data from an AVPicture into a buffer.
4027 * The data is stored compactly, without any gaps for alignment or padding
4028 * which may be applied by avpicture_fill().
4029 *
4030 * @see avpicture_get_size()
4031 *
4032 * @param[in] src AVPicture containing image data
4033 * @param[in] pix_fmt The format in which the picture data is stored.
4034 * @param[in] width the width of the image in pixels.
4035 * @param[in] height the height of the image in pixels.
4036 * @param[out] dest A buffer into which picture data will be copied.
4037 * @param[in] dest_size The size of 'dest'.
4038 * @return The number of bytes written to dest, or a negative value (error code) on error.
4039 */
4040 int avpicture_layout(const AVPicture* src, enum AVPixelFormat pix_fmt,
4041 int width, int height,
4042 unsigned char *dest, int dest_size);
4043
4044 /**
4045 * Calculate the size in bytes that a picture of the given width and height
4046 * would occupy if stored in the given picture format.
4047 * Note that this returns the size of a compact representation as generated
4048 * by avpicture_layout(), which can be smaller than the size required for e.g.
4049 * avpicture_fill().
4050 *
4051 * @param pix_fmt the given picture format
4052 * @param width the width of the image
4053 * @param height the height of the image
4054 * @return Image data size in bytes or -1 on error (e.g. too large dimensions).
4055 */
4056 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
4057
4058 #if FF_API_DEINTERLACE
4059 /**
4060 * deinterlace - if not supported return -1
4061 *
4062 * @deprecated - use yadif (in libavfilter) instead
4063 */
4064 attribute_deprecated
4065 int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
4066 enum AVPixelFormat pix_fmt, int width, int height);
4067 #endif
4068 /**
4069 * Copy image src to dst. Wraps av_picture_data_copy() above.
4070 */
4071 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4072 enum AVPixelFormat pix_fmt, int width, int height);
4073
4074 /**
4075 * Crop image top and left side.
4076 */
4077 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4078 enum AVPixelFormat pix_fmt, int top_band, int left_band);
4079
4080 /**
4081 * Pad image.
4082 */
4083 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
4084 int padtop, int padbottom, int padleft, int padright, int *color);
4085
4086 /**
4087 * @}
4088 */
4089
4090 /**
4091 * @defgroup lavc_misc Utility functions
4092 * @ingroup libavc
4093 *
4094 * Miscellaneous utility functions related to both encoding and decoding
4095 * (or neither).
4096 * @{
4097 */
4098
4099 /**
4100 * @defgroup lavc_misc_pixfmt Pixel formats
4101 *
4102 * Functions for working with pixel formats.
4103 * @{
4104 */
4105
4106 /**
4107 * @deprecated Use av_pix_fmt_get_chroma_sub_sample
4108 */
4109
4110 void attribute_deprecated avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
4111
4112 /**
4113 * Return a value representing the fourCC code associated to the
4114 * pixel format pix_fmt, or 0 if no associated fourCC code can be
4115 * found.
4116 */
4117 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
4118
4119 #define FF_LOSS_RESOLUTION 0x0001 /**< loss due to resolution change */
4120 #define FF_LOSS_DEPTH 0x0002 /**< loss due to color depth change */
4121 #define FF_LOSS_COLORSPACE 0x0004 /**< loss due to color space conversion */
4122 #define FF_LOSS_ALPHA 0x0008 /**< loss of alpha bits */
4123 #define FF_LOSS_COLORQUANT 0x0010 /**< loss due to color quantization */
4124 #define FF_LOSS_CHROMA 0x0020 /**< loss of chroma (e.g. RGB to gray conversion) */
4125
4126 /**
4127 * Compute what kind of losses will occur when converting from one specific
4128 * pixel format to another.
4129 * When converting from one pixel format to another, information loss may occur.
4130 * For example, when converting from RGB24 to GRAY, the color information will
4131 * be lost. Similarly, other losses occur when converting from some formats to
4132 * other formats. These losses can involve loss of chroma, but also loss of
4133 * resolution, loss of color depth, loss due to the color space conversion, loss
4134 * of the alpha bits or loss due to color quantization.
4135 * avcodec_get_fix_fmt_loss() informs you about the various types of losses
4136 * which will occur when converting from one pixel format to another.
4137 *
4138 * @param[in] dst_pix_fmt destination pixel format
4139 * @param[in] src_pix_fmt source pixel format
4140 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4141 * @return Combination of flags informing you what kind of losses will occur.
4142 */
4143 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
4144 int has_alpha);
4145
4146 /**
4147 * Find the best pixel format to convert to given a certain source pixel
4148 * format. When converting from one pixel format to another, information loss
4149 * may occur. For example, when converting from RGB24 to GRAY, the color
4150 * information will be lost. Similarly, other losses occur when converting from
4151 * some formats to other formats. avcodec_find_best_pix_fmt2() searches which of
4152 * the given pixel formats should be used to suffer the least amount of loss.
4153 * The pixel formats from which it chooses one, are determined by the
4154 * pix_fmt_list parameter.
4155 *
4156 *
4157 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
4158 * @param[in] src_pix_fmt source pixel format
4159 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4160 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4161 * @return The best pixel format to convert to or -1 if none was found.
4162 */
4163 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat *pix_fmt_list,
4164 enum AVPixelFormat src_pix_fmt,
4165 int has_alpha, int *loss_ptr);
4166
4167 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
4168
4169 /**
4170 * @}
4171 */
4172
4173 #if FF_API_SET_DIMENSIONS
4174 /**
4175 * @deprecated this function is not supposed to be used from outside of lavc
4176 */
4177 attribute_deprecated
4178 void avcodec_set_dimensions(AVCodecContext *s, int width, int height);
4179 #endif
4180
4181 /**
4182 * Put a string representing the codec tag codec_tag in buf.
4183 *
4184 * @param buf buffer to place codec tag in
4185 * @param buf_size size in bytes of buf
4186 * @param codec_tag codec tag to assign
4187 * @return the length of the string that would have been generated if
4188 * enough space had been available, excluding the trailing null
4189 */
4190 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
4191
4192 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
4193
4194 /**
4195 * Return a name for the specified profile, if available.
4196 *
4197 * @param codec the codec that is searched for the given profile
4198 * @param profile the profile value for which a name is requested
4199 * @return A name for the profile if found, NULL otherwise.
4200 */
4201 const char *av_get_profile_name(const AVCodec *codec, int profile);
4202
4203 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
4204 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
4205 //FIXME func typedef
4206
4207 /**
4208 * Fill audio frame data and linesize.
4209 * AVFrame extended_data channel pointers are allocated if necessary for
4210 * planar audio.
4211 *
4212 * @param frame the AVFrame
4213 * frame->nb_samples must be set prior to calling the
4214 * function. This function fills in frame->data,
4215 * frame->extended_data, frame->linesize[0].
4216 * @param nb_channels channel count
4217 * @param sample_fmt sample format
4218 * @param buf buffer to use for frame data
4219 * @param buf_size size of buffer
4220 * @param align plane size sample alignment (0 = default)
4221 * @return 0 on success, negative error code on failure
4222 */
4223 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
4224 enum AVSampleFormat sample_fmt, const uint8_t *buf,
4225 int buf_size, int align);
4226
4227 /**
4228 * Reset the internal decoder state / flush internal buffers. Should be called
4229 * e.g. when seeking or when switching to a different stream.
4230 *
4231 * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
4232 * this invalidates the frames previously returned from the decoder. When
4233 * refcounted frames are used, the decoder just releases any references it might
4234 * keep internally, but the caller's reference remains valid.
4235 */
4236 void avcodec_flush_buffers(AVCodecContext *avctx);
4237
4238 /**
4239 * Return codec bits per sample.
4240 *
4241 * @param[in] codec_id the codec
4242 * @return Number of bits per sample or zero if unknown for the given codec.
4243 */
4244 int av_get_bits_per_sample(enum AVCodecID codec_id);
4245
4246 /**
4247 * Return codec bits per sample.
4248 * Only return non-zero if the bits per sample is exactly correct, not an
4249 * approximation.
4250 *
4251 * @param[in] codec_id the codec
4252 * @return Number of bits per sample or zero if unknown for the given codec.
4253 */
4254 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
4255
4256 /**
4257 * Return audio frame duration.
4258 *
4259 * @param avctx codec context
4260 * @param frame_bytes size of the frame, or 0 if unknown
4261 * @return frame duration, in samples, if known. 0 if not able to
4262 * determine.
4263 */
4264 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4265
4266
4267 typedef struct AVBitStreamFilterContext {
4268 void *priv_data;
4269 struct AVBitStreamFilter *filter;
4270 AVCodecParserContext *parser;
4271 struct AVBitStreamFilterContext *next;
4272 } AVBitStreamFilterContext;
4273
4274
4275 typedef struct AVBitStreamFilter {
4276 const char *name;
4277 int priv_data_size;
4278 int (*filter)(AVBitStreamFilterContext *bsfc,
4279 AVCodecContext *avctx, const char *args,
4280 uint8_t **poutbuf, int *poutbuf_size,
4281 const uint8_t *buf, int buf_size, int keyframe);
4282 void (*close)(AVBitStreamFilterContext *bsfc);
4283 struct AVBitStreamFilter *next;
4284 } AVBitStreamFilter;
4285
4286 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4287 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4288 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4289 AVCodecContext *avctx, const char *args,
4290 uint8_t **poutbuf, int *poutbuf_size,
4291 const uint8_t *buf, int buf_size, int keyframe);
4292 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4293
4294 AVBitStreamFilter *av_bitstream_filter_next(const AVBitStreamFilter *f);
4295
4296 /* memory */
4297
4298 /**
4299 * Allocate a buffer with padding, reusing the given one if large enough.
4300 *
4301 * Same behaviour av_fast_malloc but the buffer has additional
4302 * FF_INPUT_PADDING_SIZE at the end which will always memset to 0.
4303 *
4304 */
4305 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4306
4307 /**
4308 * Encode extradata length to a buffer. Used by xiph codecs.
4309 *
4310 * @param s buffer to write to; must be at least (v/255+1) bytes long
4311 * @param v size of extradata in bytes
4312 * @return number of bytes written to the buffer.
4313 */
4314 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
4315
4316 #if FF_API_MISSING_SAMPLE
4317 /**
4318 * Log a generic warning message about a missing feature. This function is
4319 * intended to be used internally by Libav (libavcodec, libavformat, etc.)
4320 * only, and would normally not be used by applications.
4321 * @param[in] avc a pointer to an arbitrary struct of which the first field is
4322 * a pointer to an AVClass struct
4323 * @param[in] feature string containing the name of the missing feature
4324 * @param[in] want_sample indicates if samples are wanted which exhibit this feature.
4325 * If want_sample is non-zero, additional verbage will be added to the log
4326 * message which tells the user how to report samples to the development
4327 * mailing list.
4328 * @deprecated Use avpriv_report_missing_feature() instead.
4329 */
4330 attribute_deprecated
4331 void av_log_missing_feature(void *avc, const char *feature, int want_sample);
4332
4333 /**
4334 * Log a generic warning message asking for a sample. This function is
4335 * intended to be used internally by Libav (libavcodec, libavformat, etc.)
4336 * only, and would normally not be used by applications.
4337 * @param[in] avc a pointer to an arbitrary struct of which the first field is
4338 * a pointer to an AVClass struct
4339 * @param[in] msg string containing an optional message, or NULL if no message
4340 * @deprecated Use avpriv_request_sample() instead.
4341 */
4342 attribute_deprecated
4343 void av_log_ask_for_sample(void *avc, const char *msg, ...) av_printf_format(2, 3);
4344 #endif /* FF_API_MISSING_SAMPLE */
4345
4346 /**
4347 * Register the hardware accelerator hwaccel.
4348 */
4349 void av_register_hwaccel(AVHWAccel *hwaccel);
4350
4351 /**
4352 * If hwaccel is NULL, returns the first registered hardware accelerator,
4353 * if hwaccel is non-NULL, returns the next registered hardware accelerator
4354 * after hwaccel, or NULL if hwaccel is the last one.
4355 */
4356 AVHWAccel *av_hwaccel_next(const AVHWAccel *hwaccel);
4357
4358
4359 /**
4360 * Lock operation used by lockmgr
4361 */
4362 enum AVLockOp {
4363 AV_LOCK_CREATE, ///< Create a mutex
4364 AV_LOCK_OBTAIN, ///< Lock the mutex
4365 AV_LOCK_RELEASE, ///< Unlock the mutex
4366 AV_LOCK_DESTROY, ///< Free mutex resources
4367 };
4368
4369 /**
4370 * Register a user provided lock manager supporting the operations
4371 * specified by AVLockOp. mutex points to a (void *) where the
4372 * lockmgr should store/get a pointer to a user allocated mutex. It's
4373 * NULL upon AV_LOCK_CREATE and != NULL for all other ops.
4374 *
4375 * @param cb User defined callback. Note: Libav may invoke calls to this
4376 * callback during the call to av_lockmgr_register().
4377 * Thus, the application must be prepared to handle that.
4378 * If cb is set to NULL the lockmgr will be unregistered.
4379 * Also note that during unregistration the previously registered
4380 * lockmgr callback may also be invoked.
4381 */
4382 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
4383
4384 /**
4385 * Get the type of the given codec.
4386 */
4387 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
4388
4389 /**
4390 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
4391 * with no corresponding avcodec_close()), 0 otherwise.
4392 */
4393 int avcodec_is_open(AVCodecContext *s);
4394
4395 /**
4396 * @return a non-zero number if codec is an encoder, zero otherwise
4397 */
4398 int av_codec_is_encoder(const AVCodec *codec);
4399
4400 /**
4401 * @return a non-zero number if codec is a decoder, zero otherwise
4402 */
4403 int av_codec_is_decoder(const AVCodec *codec);
4404
4405 /**
4406 * @return descriptor for given codec ID or NULL if no descriptor exists.
4407 */
4408 const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
4409
4410 /**
4411 * Iterate over all codec descriptors known to libavcodec.
4412 *
4413 * @param prev previous descriptor. NULL to get the first descriptor.
4414 *
4415 * @return next descriptor or NULL after the last descriptor
4416 */
4417 const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
4418
4419 /**
4420 * @return codec descriptor with the given name or NULL if no such descriptor
4421 * exists.
4422 */
4423 const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
4424
4425 /**
4426 * @}
4427 */
4428
4429 #endif /* AVCODEC_AVCODEC_H */