2 * copyright (c) 2001 Fabrice Bellard
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
27 * Libavcodec external API header
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/channel_layout.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/frame.h"
39 #include "libavutil/log.h"
40 #include "libavutil/pixfmt.h"
41 #include "libavutil/rational.h"
45 #if FF_API_FAST_MALLOC
46 // to provide fast_*alloc
47 #include "libavutil/mem.h"
51 * @defgroup libavc Encoding/Decoding Library
54 * @defgroup lavc_decoding Decoding
58 * @defgroup lavc_encoding Encoding
62 * @defgroup lavc_codec Codecs
64 * @defgroup lavc_codec_native Native Codecs
67 * @defgroup lavc_codec_wrappers External library wrappers
70 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
74 * @defgroup lavc_internal Internal
82 * @defgroup lavc_core Core functions/structures.
85 * Basic definitions, functions for querying libavcodec capabilities,
86 * allocating core structures, etc.
92 * Identify the syntax and semantics of the bitstream.
93 * The principle is roughly:
94 * Two decoders with the same ID can decode the same streams.
95 * Two encoders with the same ID can encode compatible streams.
96 * There may be slight deviations from the principle due to implementation
99 * If you add a codec ID to this list, add it so that
100 * 1. no value of a existing codec ID changes (that would break ABI),
101 * 2. Give it a value which when taken as ASCII is recognized uniquely by a human as this specific codec.
102 * This ensures that 2 forks can independently add AVCodecIDs without producing conflicts.
104 * After adding new codec IDs, do not forget to add an entry to the codec
105 * descriptor list and bump libavcodec minor version.
111 AV_CODEC_ID_MPEG1VIDEO,
112 AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
114 AV_CODEC_ID_MPEG2VIDEO_XVMC,
115 #endif /* FF_API_XVMC */
126 AV_CODEC_ID_RAWVIDEO,
127 AV_CODEC_ID_MSMPEG4V1,
128 AV_CODEC_ID_MSMPEG4V2,
129 AV_CODEC_ID_MSMPEG4V3,
152 AV_CODEC_ID_INTERPLAY_VIDEO,
159 AV_CODEC_ID_MSVIDEO1,
164 AV_CODEC_ID_TRUEMOTION1,
165 AV_CODEC_ID_VMDVIDEO,
190 AV_CODEC_ID_TRUEMOTION2,
196 AV_CODEC_ID_SMACKVIDEO,
201 AV_CODEC_ID_JPEG2000,
207 AV_CODEC_ID_DSICINVIDEO,
208 AV_CODEC_ID_TIERTEXSEQVIDEO,
216 AV_CODEC_ID_BETHSOFTVID,
228 AV_CODEC_ID_ESCAPE124,
232 AV_CODEC_ID_MOTIONPIXELS,
244 AV_CODEC_ID_FLASHSV2,
245 AV_CODEC_ID_CDGRAPHICS,
248 AV_CODEC_ID_BINKVIDEO,
249 AV_CODEC_ID_IFF_ILBM,
250 AV_CODEC_ID_IFF_BYTERUN1,
256 AV_CODEC_ID_A64_MULTI,
257 AV_CODEC_ID_A64_MULTI5,
260 AV_CODEC_ID_LAGARITH,
264 AV_CODEC_ID_WMV3IMAGE,
265 AV_CODEC_ID_VC1IMAGE,
267 AV_CODEC_ID_BMV_VIDEO,
274 AV_CODEC_ID_ZEROCODEC,
283 AV_CODEC_ID_ESCAPE130_DEPRECATED,
284 AV_CODEC_ID_G2M_DEPRECATED,
285 AV_CODEC_ID_WEBP_DEPRECATED,
286 AV_CODEC_ID_HNM4_VIDEO,
287 AV_CODEC_ID_HEVC_DEPRECATED,
289 AV_CODEC_ID_ALIAS_PIX,
290 AV_CODEC_ID_BRENDER_PIX_DEPRECATED,
291 AV_CODEC_ID_PAF_VIDEO_DEPRECATED,
292 AV_CODEC_ID_EXR_DEPRECATED,
293 AV_CODEC_ID_VP7_DEPRECATED,
294 AV_CODEC_ID_SANM_DEPRECATED,
295 AV_CODEC_ID_SGIRLE_DEPRECATED,
296 AV_CODEC_ID_MVC1_DEPRECATED,
297 AV_CODEC_ID_MVC2_DEPRECATED,
299 AV_CODEC_ID_BRENDER_PIX= MKBETAG('B','P','I','X'),
300 AV_CODEC_ID_Y41P = MKBETAG('Y','4','1','P'),
301 AV_CODEC_ID_ESCAPE130 = MKBETAG('E','1','3','0'),
302 AV_CODEC_ID_EXR = MKBETAG('0','E','X','R'),
303 AV_CODEC_ID_AVRP = MKBETAG('A','V','R','P'),
305 AV_CODEC_ID_012V = MKBETAG('0','1','2','V'),
306 AV_CODEC_ID_G2M = MKBETAG( 0 ,'G','2','M'),
307 AV_CODEC_ID_AVUI = MKBETAG('A','V','U','I'),
308 AV_CODEC_ID_AYUV = MKBETAG('A','Y','U','V'),
309 AV_CODEC_ID_TARGA_Y216 = MKBETAG('T','2','1','6'),
310 AV_CODEC_ID_V308 = MKBETAG('V','3','0','8'),
311 AV_CODEC_ID_V408 = MKBETAG('V','4','0','8'),
312 AV_CODEC_ID_YUV4 = MKBETAG('Y','U','V','4'),
313 AV_CODEC_ID_SANM = MKBETAG('S','A','N','M'),
314 AV_CODEC_ID_PAF_VIDEO = MKBETAG('P','A','F','V'),
315 AV_CODEC_ID_AVRN = MKBETAG('A','V','R','n'),
316 AV_CODEC_ID_CPIA = MKBETAG('C','P','I','A'),
317 AV_CODEC_ID_XFACE = MKBETAG('X','F','A','C'),
318 AV_CODEC_ID_SGIRLE = MKBETAG('S','G','I','R'),
319 AV_CODEC_ID_MVC1 = MKBETAG('M','V','C','1'),
320 AV_CODEC_ID_MVC2 = MKBETAG('M','V','C','2'),
321 AV_CODEC_ID_SNOW = MKBETAG('S','N','O','W'),
322 AV_CODEC_ID_WEBP = MKBETAG('W','E','B','P'),
323 AV_CODEC_ID_SMVJPEG = MKBETAG('S','M','V','J'),
324 AV_CODEC_ID_HEVC = MKBETAG('H','2','6','5'),
325 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
326 AV_CODEC_ID_VP7 = MKBETAG('V','P','7','0'),
328 /* various PCM "codecs" */
329 AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
330 AV_CODEC_ID_PCM_S16LE = 0x10000,
331 AV_CODEC_ID_PCM_S16BE,
332 AV_CODEC_ID_PCM_U16LE,
333 AV_CODEC_ID_PCM_U16BE,
336 AV_CODEC_ID_PCM_MULAW,
337 AV_CODEC_ID_PCM_ALAW,
338 AV_CODEC_ID_PCM_S32LE,
339 AV_CODEC_ID_PCM_S32BE,
340 AV_CODEC_ID_PCM_U32LE,
341 AV_CODEC_ID_PCM_U32BE,
342 AV_CODEC_ID_PCM_S24LE,
343 AV_CODEC_ID_PCM_S24BE,
344 AV_CODEC_ID_PCM_U24LE,
345 AV_CODEC_ID_PCM_U24BE,
346 AV_CODEC_ID_PCM_S24DAUD,
347 AV_CODEC_ID_PCM_ZORK,
348 AV_CODEC_ID_PCM_S16LE_PLANAR,
350 AV_CODEC_ID_PCM_F32BE,
351 AV_CODEC_ID_PCM_F32LE,
352 AV_CODEC_ID_PCM_F64BE,
353 AV_CODEC_ID_PCM_F64LE,
354 AV_CODEC_ID_PCM_BLURAY,
357 AV_CODEC_ID_PCM_S8_PLANAR,
358 AV_CODEC_ID_PCM_S24LE_PLANAR_DEPRECATED,
359 AV_CODEC_ID_PCM_S32LE_PLANAR_DEPRECATED,
360 AV_CODEC_ID_PCM_S24LE_PLANAR = MKBETAG(24,'P','S','P'),
361 AV_CODEC_ID_PCM_S32LE_PLANAR = MKBETAG(32,'P','S','P'),
362 AV_CODEC_ID_PCM_S16BE_PLANAR = MKBETAG('P','S','P',16),
364 /* various ADPCM codecs */
365 AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
366 AV_CODEC_ID_ADPCM_IMA_WAV,
367 AV_CODEC_ID_ADPCM_IMA_DK3,
368 AV_CODEC_ID_ADPCM_IMA_DK4,
369 AV_CODEC_ID_ADPCM_IMA_WS,
370 AV_CODEC_ID_ADPCM_IMA_SMJPEG,
371 AV_CODEC_ID_ADPCM_MS,
372 AV_CODEC_ID_ADPCM_4XM,
373 AV_CODEC_ID_ADPCM_XA,
374 AV_CODEC_ID_ADPCM_ADX,
375 AV_CODEC_ID_ADPCM_EA,
376 AV_CODEC_ID_ADPCM_G726,
377 AV_CODEC_ID_ADPCM_CT,
378 AV_CODEC_ID_ADPCM_SWF,
379 AV_CODEC_ID_ADPCM_YAMAHA,
380 AV_CODEC_ID_ADPCM_SBPRO_4,
381 AV_CODEC_ID_ADPCM_SBPRO_3,
382 AV_CODEC_ID_ADPCM_SBPRO_2,
383 AV_CODEC_ID_ADPCM_THP,
384 AV_CODEC_ID_ADPCM_IMA_AMV,
385 AV_CODEC_ID_ADPCM_EA_R1,
386 AV_CODEC_ID_ADPCM_EA_R3,
387 AV_CODEC_ID_ADPCM_EA_R2,
388 AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
389 AV_CODEC_ID_ADPCM_IMA_EA_EACS,
390 AV_CODEC_ID_ADPCM_EA_XAS,
391 AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
392 AV_CODEC_ID_ADPCM_IMA_ISS,
393 AV_CODEC_ID_ADPCM_G722,
394 AV_CODEC_ID_ADPCM_IMA_APC,
395 AV_CODEC_ID_ADPCM_VIMA_DEPRECATED,
396 AV_CODEC_ID_ADPCM_VIMA = MKBETAG('V','I','M','A'),
397 AV_CODEC_ID_VIMA = MKBETAG('V','I','M','A'),
398 AV_CODEC_ID_ADPCM_AFC = MKBETAG('A','F','C',' '),
399 AV_CODEC_ID_ADPCM_IMA_OKI = MKBETAG('O','K','I',' '),
400 AV_CODEC_ID_ADPCM_DTK = MKBETAG('D','T','K',' '),
401 AV_CODEC_ID_ADPCM_IMA_RAD = MKBETAG('R','A','D',' '),
402 AV_CODEC_ID_ADPCM_G726LE = MKBETAG('6','2','7','G'),
405 AV_CODEC_ID_AMR_NB = 0x12000,
408 /* RealAudio codecs*/
409 AV_CODEC_ID_RA_144 = 0x13000,
412 /* various DPCM codecs */
413 AV_CODEC_ID_ROQ_DPCM = 0x14000,
414 AV_CODEC_ID_INTERPLAY_DPCM,
415 AV_CODEC_ID_XAN_DPCM,
416 AV_CODEC_ID_SOL_DPCM,
419 AV_CODEC_ID_MP2 = 0x15000,
420 AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
430 AV_CODEC_ID_VMDAUDIO,
436 AV_CODEC_ID_WESTWOOD_SND1,
437 AV_CODEC_ID_GSM, ///< as in Berlin toast format
440 AV_CODEC_ID_TRUESPEECH,
442 AV_CODEC_ID_SMACKAUDIO,
445 AV_CODEC_ID_DSICINAUDIO,
447 AV_CODEC_ID_MUSEPACK7,
449 AV_CODEC_ID_GSM_MS, /* as found in WAV */
455 AV_CODEC_ID_NELLYMOSER,
456 AV_CODEC_ID_MUSEPACK8,
458 AV_CODEC_ID_WMAVOICE,
460 AV_CODEC_ID_WMALOSSLESS,
469 AV_CODEC_ID_BINKAUDIO_RDFT,
470 AV_CODEC_ID_BINKAUDIO_DCT,
471 AV_CODEC_ID_AAC_LATM,
476 AV_CODEC_ID_8SVX_EXP,
477 AV_CODEC_ID_8SVX_FIB,
478 AV_CODEC_ID_BMV_AUDIO,
482 AV_CODEC_ID_OPUS_DEPRECATED,
483 AV_CODEC_ID_COMFORT_NOISE,
484 AV_CODEC_ID_TAK_DEPRECATED,
485 AV_CODEC_ID_METASOUND,
486 AV_CODEC_ID_PAF_AUDIO_DEPRECATED,
487 AV_CODEC_ID_FFWAVESYNTH = MKBETAG('F','F','W','S'),
488 AV_CODEC_ID_SONIC = MKBETAG('S','O','N','C'),
489 AV_CODEC_ID_SONIC_LS = MKBETAG('S','O','N','L'),
490 AV_CODEC_ID_PAF_AUDIO = MKBETAG('P','A','F','A'),
491 AV_CODEC_ID_OPUS = MKBETAG('O','P','U','S'),
492 AV_CODEC_ID_TAK = MKBETAG('t','B','a','K'),
493 AV_CODEC_ID_EVRC = MKBETAG('s','e','v','c'),
494 AV_CODEC_ID_SMV = MKBETAG('s','s','m','v'),
495 AV_CODEC_ID_DSD_LSBF = MKBETAG('D','S','D','L'),
496 AV_CODEC_ID_DSD_MSBF = MKBETAG('D','S','D','M'),
497 AV_CODEC_ID_DSD_LSBF_PLANAR = MKBETAG('D','S','D','1'),
498 AV_CODEC_ID_DSD_MSBF_PLANAR = MKBETAG('D','S','D','8'),
500 /* subtitle codecs */
501 AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
502 AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
503 AV_CODEC_ID_DVB_SUBTITLE,
504 AV_CODEC_ID_TEXT, ///< raw UTF-8 text
507 AV_CODEC_ID_MOV_TEXT,
508 AV_CODEC_ID_HDMV_PGS_SUBTITLE,
509 AV_CODEC_ID_DVB_TELETEXT,
511 AV_CODEC_ID_MICRODVD = MKBETAG('m','D','V','D'),
512 AV_CODEC_ID_EIA_608 = MKBETAG('c','6','0','8'),
513 AV_CODEC_ID_JACOSUB = MKBETAG('J','S','U','B'),
514 AV_CODEC_ID_SAMI = MKBETAG('S','A','M','I'),
515 AV_CODEC_ID_REALTEXT = MKBETAG('R','T','X','T'),
516 AV_CODEC_ID_SUBVIEWER1 = MKBETAG('S','b','V','1'),
517 AV_CODEC_ID_SUBVIEWER = MKBETAG('S','u','b','V'),
518 AV_CODEC_ID_SUBRIP = MKBETAG('S','R','i','p'),
519 AV_CODEC_ID_WEBVTT = MKBETAG('W','V','T','T'),
520 AV_CODEC_ID_MPL2 = MKBETAG('M','P','L','2'),
521 AV_CODEC_ID_VPLAYER = MKBETAG('V','P','l','r'),
522 AV_CODEC_ID_PJS = MKBETAG('P','h','J','S'),
523 AV_CODEC_ID_ASS = MKBETAG('A','S','S',' '), ///< ASS as defined in Matroska
525 /* other specific kind of codecs (generally used for attachments) */
526 AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
527 AV_CODEC_ID_TTF = 0x18000,
528 AV_CODEC_ID_BINTEXT = MKBETAG('B','T','X','T'),
529 AV_CODEC_ID_XBIN = MKBETAG('X','B','I','N'),
530 AV_CODEC_ID_IDF = MKBETAG( 0 ,'I','D','F'),
531 AV_CODEC_ID_OTF = MKBETAG( 0 ,'O','T','F'),
532 AV_CODEC_ID_SMPTE_KLV = MKBETAG('K','L','V','A'),
533 AV_CODEC_ID_DVD_NAV = MKBETAG('D','N','A','V'),
534 AV_CODEC_ID_TIMED_ID3 = MKBETAG('T','I','D','3'),
537 AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
539 AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
540 * stream (only used by libavformat) */
541 AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
542 * stream (only used by libavformat) */
543 AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
546 #include "old_codec_ids.h"
551 * This struct describes the properties of a single codec described by an
553 * @see avcodec_get_descriptor()
555 typedef struct AVCodecDescriptor {
557 enum AVMediaType type;
559 * Name of the codec described by this descriptor. It is non-empty and
560 * unique for each codec descriptor. It should contain alphanumeric
561 * characters and '_' only.
565 * A more descriptive name for this codec. May be NULL.
567 const char *long_name;
569 * Codec properties, a combination of AV_CODEC_PROP_* flags.
575 * Codec uses only intra compression.
578 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
580 * Codec supports lossy compression. Audio and video codecs only.
581 * @note a codec may support both lossy and lossless
584 #define AV_CODEC_PROP_LOSSY (1 << 1)
586 * Codec supports lossless compression. Audio and video codecs only.
588 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
590 * Subtitle codec is bitmap based
591 * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
593 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
595 * Subtitle codec is text based.
596 * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
598 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
601 * @ingroup lavc_decoding
602 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
603 * This is mainly needed because some optimized bitstream readers read
604 * 32 or 64 bit at once and could read over the end.<br>
605 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
606 * MPEG bitstreams could cause overread and segfault.
608 #define FF_INPUT_BUFFER_PADDING_SIZE 16
611 * @ingroup lavc_encoding
612 * minimum encoding buffer size
613 * Used to avoid some checks during header writing.
615 #define FF_MIN_BUFFER_SIZE 16384
619 * @ingroup lavc_encoding
620 * motion estimation type.
623 ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
627 ME_EPZS, ///< enhanced predictive zonal search
628 ME_X1, ///< reserved for experiments
629 ME_HEX, ///< hexagon based search
630 ME_UMH, ///< uneven multi-hexagon search
631 ME_TESA, ///< transformed exhaustive search algorithm
632 ME_ITER=50, ///< iterative search
636 * @ingroup lavc_decoding
639 /* We leave some space between them for extensions (drop some
640 * keyframes for intra-only or drop just some bidir frames). */
641 AVDISCARD_NONE =-16, ///< discard nothing
642 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
643 AVDISCARD_NONREF = 8, ///< discard all non reference
644 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
645 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
646 AVDISCARD_ALL = 48, ///< discard all
649 enum AVColorPrimaries{
650 AVCOL_PRI_BT709 = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 / SMPTE RP177 Annex B
651 AVCOL_PRI_UNSPECIFIED = 2,
652 AVCOL_PRI_BT470M = 4,
653 AVCOL_PRI_BT470BG = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
654 AVCOL_PRI_SMPTE170M = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
655 AVCOL_PRI_SMPTE240M = 7, ///< functionally identical to above
657 AVCOL_PRI_BT2020 = 9, ///< ITU-R BT2020
658 AVCOL_PRI_NB , ///< Not part of ABI
661 enum AVColorTransferCharacteristic{
662 AVCOL_TRC_BT709 = 1, ///< also ITU-R BT1361
663 AVCOL_TRC_UNSPECIFIED = 2,
664 AVCOL_TRC_GAMMA22 = 4, ///< also ITU-R BT470M / ITU-R BT1700 625 PAL & SECAM
665 AVCOL_TRC_GAMMA28 = 5, ///< also ITU-R BT470BG
666 AVCOL_TRC_SMPTE170M = 6, ///< also ITU-R BT601-6 525 or 625 / ITU-R BT1358 525 or 625 / ITU-R BT1700 NTSC
667 AVCOL_TRC_SMPTE240M = 7,
668 AVCOL_TRC_LINEAR = 8, ///< "Linear transfer characteristics"
669 AVCOL_TRC_LOG = 9, ///< "Logarithmic transfer characteristic (100:1 range)"
670 AVCOL_TRC_LOG_SQRT = 10, ///< "Logarithmic transfer characteristic (100 * Sqrt( 10 ) : 1 range)"
671 AVCOL_TRC_IEC61966_2_4 = 11, ///< IEC 61966-2-4
672 AVCOL_TRC_BT1361_ECG = 12, ///< ITU-R BT1361 Extended Colour Gamut
673 AVCOL_TRC_IEC61966_2_1 = 13, ///< IEC 61966-2-1 (sRGB or sYCC)
674 AVCOL_TRC_BT2020_10 = 14, ///< ITU-R BT2020 for 10 bit system
675 AVCOL_TRC_BT2020_12 = 15, ///< ITU-R BT2020 for 12 bit system
676 AVCOL_TRC_NB , ///< Not part of ABI
680 * X X 3 4 X X are luma samples,
681 * 1 2 1-6 are possible chroma positions
682 * X X 5 6 X 0 is undefined/unknown position
684 enum AVChromaLocation{
685 AVCHROMA_LOC_UNSPECIFIED = 0,
686 AVCHROMA_LOC_LEFT = 1, ///< mpeg2/4, h264 default
687 AVCHROMA_LOC_CENTER = 2, ///< mpeg1, jpeg, h263
688 AVCHROMA_LOC_TOPLEFT = 3, ///< DV
689 AVCHROMA_LOC_TOP = 4,
690 AVCHROMA_LOC_BOTTOMLEFT = 5,
691 AVCHROMA_LOC_BOTTOM = 6,
692 AVCHROMA_LOC_NB , ///< Not part of ABI
695 enum AVAudioServiceType {
696 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
697 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
698 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
699 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
700 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
701 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
702 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
703 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
704 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
705 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
709 * @ingroup lavc_encoding
711 typedef struct RcOverride{
714 int qscale; // If this is 0 then quality_factor will be used instead.
715 float quality_factor;
718 #if FF_API_MAX_BFRAMES
720 * @deprecated there is no libavcodec-wide limit on the number of B-frames
722 #define FF_MAX_B_FRAMES 16
726 These flags can be passed in AVCodecContext.flags before initialization.
727 Note: Not everything is supported yet.
731 * Allow decoders to produce frames with data planes that are not aligned
732 * to CPU requirements (e.g. due to cropping).
734 #define CODEC_FLAG_UNALIGNED 0x0001
735 #define CODEC_FLAG_QSCALE 0x0002 ///< Use fixed qscale.
736 #define CODEC_FLAG_4MV 0x0004 ///< 4 MV per MB allowed / advanced prediction for H.263.
737 #define CODEC_FLAG_OUTPUT_CORRUPT 0x0008 ///< Output even those frames that might be corrupted
738 #define CODEC_FLAG_QPEL 0x0010 ///< Use qpel MC.
739 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
740 #define CODEC_FLAG_MV0 0x0040 ///< Always try a MB with MV=<0,0>.
742 * The parent program guarantees that the input for B-frames containing
743 * streams is not written to for at least s->max_b_frames+1 frames, if
744 * this is not set the input will be copied.
746 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
747 #define CODEC_FLAG_PASS1 0x0200 ///< Use internal 2pass ratecontrol in first pass mode.
748 #define CODEC_FLAG_PASS2 0x0400 ///< Use internal 2pass ratecontrol in second pass mode.
749 #define CODEC_FLAG_GRAY 0x2000 ///< Only decode/encode grayscale.
752 * @deprecated edges are not used/required anymore. I.e. this flag is now always
755 #define CODEC_FLAG_EMU_EDGE 0x4000
757 #define CODEC_FLAG_PSNR 0x8000 ///< error[?] variables will be set during encoding.
758 #define CODEC_FLAG_TRUNCATED 0x00010000 /** Input bitstream might be truncated at a random
759 location instead of only at frame boundaries. */
760 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000 ///< Normalize adaptive quantization.
761 #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
762 #define CODEC_FLAG_LOW_DELAY 0x00080000 ///< Force low delay.
763 #define CODEC_FLAG_GLOBAL_HEADER 0x00400000 ///< Place global headers in extradata instead of every keyframe.
764 #define CODEC_FLAG_BITEXACT 0x00800000 ///< Use only bitexact stuff (except (I)DCT).
765 /* Fx : Flag for h263+ extra options */
766 #define CODEC_FLAG_AC_PRED 0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
767 #define CODEC_FLAG_LOOP_FILTER 0x00000800 ///< loop filter
768 #define CODEC_FLAG_INTERLACED_ME 0x20000000 ///< interlaced motion estimation
769 #define CODEC_FLAG_CLOSED_GOP 0x80000000
770 #define CODEC_FLAG2_FAST 0x00000001 ///< Allow non spec compliant speedup tricks.
771 #define CODEC_FLAG2_NO_OUTPUT 0x00000004 ///< Skip bitstream encoding.
772 #define CODEC_FLAG2_LOCAL_HEADER 0x00000008 ///< Place global headers at every keyframe instead of in extradata.
773 #define CODEC_FLAG2_DROP_FRAME_TIMECODE 0x00002000 ///< timecode is in drop frame format. DEPRECATED!!!!
774 #define CODEC_FLAG2_IGNORE_CROP 0x00010000 ///< Discard cropping information from SPS.
776 #define CODEC_FLAG2_CHUNKS 0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
777 #define CODEC_FLAG2_SHOW_ALL 0x00400000 ///< Show all frames before the first keyframe
779 /* Unsupported options :
780 * Syntax Arithmetic coding (SAC)
781 * Reference Picture Selection
782 * Independent Segment Decoding */
784 /* codec capabilities */
786 #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
788 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
789 * If not set, it might not use get_buffer() at all or use operations that
790 * assume the buffer was allocated by avcodec_default_get_buffer.
792 #define CODEC_CAP_DR1 0x0002
793 #define CODEC_CAP_TRUNCATED 0x0008
795 /* Codec can export data for HW decoding. This flag indicates that
796 * the codec would call get_format() with list that might contain HW accelerated
797 * pixel formats (XvMC, VDPAU, VAAPI, etc). The application can pick any of them
798 * including raw image format.
799 * The application can use the passed context to determine bitstream version,
800 * chroma format, resolution etc.
802 #define CODEC_CAP_HWACCEL 0x0010
803 #endif /* FF_API_XVMC */
805 * Encoder or decoder requires flushing with NULL input at the end in order to
806 * give the complete and correct output.
808 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
809 * with NULL data. The user can still send NULL data to the public encode
810 * or decode function, but libavcodec will not pass it along to the codec
811 * unless this flag is set.
814 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
815 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
819 * The encoder needs to be fed with NULL data at the end of encoding until the
820 * encoder no longer returns data.
822 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
823 * flag also means that the encoder must set the pts and duration for
824 * each output packet. If this flag is not set, the pts and duration will
825 * be determined by libavcodec from the input frame.
827 #define CODEC_CAP_DELAY 0x0020
829 * Codec can be fed a final frame with a smaller size.
830 * This can be used to prevent truncation of the last audio samples.
832 #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
835 * Codec can export data for HW decoding (VDPAU).
837 #define CODEC_CAP_HWACCEL_VDPAU 0x0080
840 * Codec can output multiple frames per AVPacket
841 * Normally demuxers return one frame at a time, demuxers which do not do
842 * are connected to a parser to split what they return into proper frames.
843 * This flag is reserved to the very rare category of codecs which have a
844 * bitstream that cannot be split into frames without timeconsuming
845 * operations like full decoding. Demuxers carring such bitstreams thus
846 * may return multiple frames in a packet. This has many disadvantages like
847 * prohibiting stream copy in many cases thus it should only be considered
850 #define CODEC_CAP_SUBFRAMES 0x0100
852 * Codec is experimental and is thus avoided in favor of non experimental
855 #define CODEC_CAP_EXPERIMENTAL 0x0200
857 * Codec should fill in channel configuration and samplerate instead of container
859 #define CODEC_CAP_CHANNEL_CONF 0x0400
860 #if FF_API_NEG_LINESIZES
862 * @deprecated no codecs use this capability
864 #define CODEC_CAP_NEG_LINESIZES 0x0800
867 * Codec supports frame-level multithreading.
869 #define CODEC_CAP_FRAME_THREADS 0x1000
871 * Codec supports slice-based (or partition-based) multithreading.
873 #define CODEC_CAP_SLICE_THREADS 0x2000
875 * Codec supports changed parameters at any point.
877 #define CODEC_CAP_PARAM_CHANGE 0x4000
879 * Codec supports avctx->thread_count == 0 (auto).
881 #define CODEC_CAP_AUTO_THREADS 0x8000
883 * Audio encoder supports receiving a different number of samples in each call.
885 #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
887 * Codec is intra only.
889 #define CODEC_CAP_INTRA_ONLY 0x40000000
893 #define CODEC_CAP_LOSSLESS 0x80000000
896 //The following defines may change, don't expect compatibility if you use them.
897 #define MB_TYPE_INTRA4x4 0x0001
898 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
899 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
900 #define MB_TYPE_16x16 0x0008
901 #define MB_TYPE_16x8 0x0010
902 #define MB_TYPE_8x16 0x0020
903 #define MB_TYPE_8x8 0x0040
904 #define MB_TYPE_INTERLACED 0x0080
905 #define MB_TYPE_DIRECT2 0x0100 //FIXME
906 #define MB_TYPE_ACPRED 0x0200
907 #define MB_TYPE_GMC 0x0400
908 #define MB_TYPE_SKIP 0x0800
909 #define MB_TYPE_P0L0 0x1000
910 #define MB_TYPE_P1L0 0x2000
911 #define MB_TYPE_P0L1 0x4000
912 #define MB_TYPE_P1L1 0x8000
913 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
914 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
915 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
916 #define MB_TYPE_QUANT 0x00010000
917 #define MB_TYPE_CBP 0x00020000
918 //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
923 * This specifies the area which should be displayed.
924 * Note there may be multiple such areas for one frame.
926 typedef struct AVPanScan{
929 * - encoding: Set by user.
930 * - decoding: Set by libavcodec.
935 * width and height in 1/16 pel
936 * - encoding: Set by user.
937 * - decoding: Set by libavcodec.
943 * position of the top left corner in 1/16 pel for up to 3 fields/frames
944 * - encoding: Set by user.
945 * - decoding: Set by libavcodec.
947 int16_t position[3][2];
950 #if FF_API_QSCALE_TYPE
951 #define FF_QSCALE_TYPE_MPEG1 0
952 #define FF_QSCALE_TYPE_MPEG2 1
953 #define FF_QSCALE_TYPE_H264 2
954 #define FF_QSCALE_TYPE_VP56 3
957 #if FF_API_GET_BUFFER
958 #define FF_BUFFER_TYPE_INTERNAL 1
959 #define FF_BUFFER_TYPE_USER 2 ///< direct rendering buffers (image is (de)allocated by user)
960 #define FF_BUFFER_TYPE_SHARED 4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
961 #define FF_BUFFER_TYPE_COPY 8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
963 #define FF_BUFFER_HINTS_VALID 0x01 // Buffer hints value is meaningful (if 0 ignore).
964 #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
965 #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
966 #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
970 * The decoder will keep a reference to the frame and may reuse it later.
972 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
975 * @defgroup lavc_packet AVPacket
977 * Types and functions for working with AVPacket.
980 enum AVPacketSideDataType {
982 AV_PKT_DATA_NEW_EXTRADATA,
985 * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
988 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
989 * s32le channel_count
990 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
991 * u64le channel_layout
992 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
994 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
999 AV_PKT_DATA_PARAM_CHANGE,
1002 * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1003 * structures with info about macroblocks relevant to splitting the
1004 * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1005 * That is, it does not necessarily contain info about all macroblocks,
1006 * as long as the distance between macroblocks in the info is smaller
1007 * than the target payload size.
1008 * Each MB info structure is 12 bytes, and is laid out as follows:
1010 * u32le bit offset from the start of the packet
1011 * u8 current quantizer at the start of the macroblock
1013 * u16le macroblock address within the GOB
1014 * u8 horizontal MV predictor
1015 * u8 vertical MV predictor
1016 * u8 horizontal MV predictor for block number 3
1017 * u8 vertical MV predictor for block number 3
1020 AV_PKT_DATA_H263_MB_INFO,
1023 * This side data should be associated with an audio stream and contains
1024 * ReplayGain information in form of the AVReplayGain struct.
1026 AV_PKT_DATA_REPLAYGAIN,
1029 * Recommmends skipping the specified number of samples
1031 * u32le number of samples to skip from start of this packet
1032 * u32le number of samples to skip from end of this packet
1033 * u8 reason for start skip
1034 * u8 reason for end skip (0=padding silence, 1=convergence)
1037 AV_PKT_DATA_SKIP_SAMPLES=70,
1040 * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1041 * the packet may contain "dual mono" audio specific to Japanese DTV
1042 * and if it is true, recommends only the selected channel to be used.
1044 * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1047 AV_PKT_DATA_JP_DUALMONO,
1050 * A list of zero terminated key/value strings. There is no end marker for
1051 * the list, so it is required to rely on the side data size to stop.
1053 AV_PKT_DATA_STRINGS_METADATA,
1056 * Subtitle event position
1064 AV_PKT_DATA_SUBTITLE_POSITION,
1067 * Data found in BlockAdditional element of matroska container. There is
1068 * no end marker for the data, so it is required to rely on the side data
1069 * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1072 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
1075 * The optional first identifier line of a WebVTT cue.
1077 AV_PKT_DATA_WEBVTT_IDENTIFIER,
1080 * The optional settings (rendering instructions) that immediately
1081 * follow the timestamp specifier of a WebVTT cue.
1083 AV_PKT_DATA_WEBVTT_SETTINGS,
1086 * A list of zero terminated key/value strings. There is no end marker for
1087 * the list, so it is required to rely on the side data size to stop. This
1088 * side data includes updated metadata which appeared in the stream.
1090 AV_PKT_DATA_METADATA_UPDATE,
1093 typedef struct AVPacketSideData {
1096 enum AVPacketSideDataType type;
1100 * This structure stores compressed data. It is typically exported by demuxers
1101 * and then passed as input to decoders, or received as output from encoders and
1102 * then passed to muxers.
1104 * For video, it should typically contain one compressed frame. For audio it may
1105 * contain several compressed frames.
1107 * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1108 * ABI. Thus it may be allocated on stack and no new fields can be added to it
1109 * without libavcodec and libavformat major bump.
1111 * The semantics of data ownership depends on the buf or destruct (deprecated)
1112 * fields. If either is set, the packet data is dynamically allocated and is
1113 * valid indefinitely until av_free_packet() is called (which in turn calls
1114 * av_buffer_unref()/the destruct callback to free the data). If neither is set,
1115 * the packet data is typically backed by some static buffer somewhere and is
1116 * only valid for a limited time (e.g. until the next read call when demuxing).
1118 * The side data is always allocated with av_malloc() and is freed in
1121 typedef struct AVPacket {
1123 * A reference to the reference-counted buffer where the packet data is
1125 * May be NULL, then the packet data is not reference-counted.
1129 * Presentation timestamp in AVStream->time_base units; the time at which
1130 * the decompressed packet will be presented to the user.
1131 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1132 * pts MUST be larger or equal to dts as presentation cannot happen before
1133 * decompression, unless one wants to view hex dumps. Some formats misuse
1134 * the terms dts and pts/cts to mean something different. Such timestamps
1135 * must be converted to true pts/dts before they are stored in AVPacket.
1139 * Decompression timestamp in AVStream->time_base units; the time at which
1140 * the packet is decompressed.
1141 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1148 * A combination of AV_PKT_FLAG values
1152 * Additional packet data that can be provided by the container.
1153 * Packet can contain several types of side information.
1155 AVPacketSideData *side_data;
1156 int side_data_elems;
1159 * Duration of this packet in AVStream->time_base units, 0 if unknown.
1160 * Equals next_pts - this_pts in presentation order.
1163 #if FF_API_DESTRUCT_PACKET
1164 attribute_deprecated
1165 void (*destruct)(struct AVPacket *);
1166 attribute_deprecated
1169 int64_t pos; ///< byte position in stream, -1 if unknown
1172 * Time difference in AVStream->time_base units from the pts of this
1173 * packet to the point at which the output from the decoder has converged
1174 * independent from the availability of previous frames. That is, the
1175 * frames are virtually identical no matter if decoding started from
1176 * the very first frame or from this keyframe.
1177 * Is AV_NOPTS_VALUE if unknown.
1178 * This field is not the display duration of the current packet.
1179 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
1182 * The purpose of this field is to allow seeking in streams that have no
1183 * keyframes in the conventional sense. It corresponds to the
1184 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
1185 * essential for some types of subtitle streams to ensure that all
1186 * subtitles are correctly displayed after seeking.
1188 int64_t convergence_duration;
1190 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1191 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1193 enum AVSideDataParamChangeFlags {
1194 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1195 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1196 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1197 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1203 struct AVCodecInternal;
1207 AV_FIELD_PROGRESSIVE,
1208 AV_FIELD_TT, //< Top coded_first, top displayed first
1209 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1210 AV_FIELD_TB, //< Top coded first, bottom displayed first
1211 AV_FIELD_BT, //< Bottom coded first, top displayed first
1215 * main external API structure.
1216 * New fields can be added to the end with minor version bumps.
1217 * Removal, reordering and changes to existing fields require a major
1219 * Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1221 * sizeof(AVCodecContext) must not be used outside libav*.
1223 typedef struct AVCodecContext {
1225 * information on struct for av_log
1226 * - set by avcodec_alloc_context3
1228 const AVClass *av_class;
1229 int log_level_offset;
1231 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1232 const struct AVCodec *codec;
1233 char codec_name[32];
1234 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1237 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1238 * This is used to work around some encoder bugs.
1239 * A demuxer should set this to what is stored in the field used to identify the codec.
1240 * If there are multiple such fields in a container then the demuxer should choose the one
1241 * which maximizes the information about the used codec.
1242 * If the codec tag field in a container is larger than 32 bits then the demuxer should
1243 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1244 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1246 * - encoding: Set by user, if not then the default based on codec_id will be used.
1247 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1249 unsigned int codec_tag;
1252 * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1253 * This is used to work around some encoder bugs.
1254 * - encoding: unused
1255 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1257 unsigned int stream_codec_tag;
1262 * Private context used for internal data.
1264 * Unlike priv_data, this is not codec-specific. It is used in general
1265 * libavcodec functions.
1267 struct AVCodecInternal *internal;
1270 * Private data of the user, can be used to carry app specific stuff.
1271 * - encoding: Set by user.
1272 * - decoding: Set by user.
1277 * the average bitrate
1278 * - encoding: Set by user; unused for constant quantizer encoding.
1279 * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
1284 * number of bits the bitstream is allowed to diverge from the reference.
1285 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1286 * - encoding: Set by user; unused for constant quantizer encoding.
1287 * - decoding: unused
1289 int bit_rate_tolerance;
1292 * Global quality for codecs which cannot change it per frame.
1293 * This should be proportional to MPEG-1/2/4 qscale.
1294 * - encoding: Set by user.
1295 * - decoding: unused
1300 * - encoding: Set by user.
1301 * - decoding: unused
1303 int compression_level;
1304 #define FF_COMPRESSION_DEFAULT -1
1308 * - encoding: Set by user.
1309 * - decoding: Set by user.
1315 * - encoding: Set by user.
1316 * - decoding: Set by user.
1321 * some codecs need / can use extradata like Huffman tables.
1322 * mjpeg: Huffman tables
1323 * rv10: additional flags
1324 * mpeg4: global headers (they can be in the bitstream or here)
1325 * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
1326 * than extradata_size to avoid problems if it is read with the bitstream reader.
1327 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1328 * - encoding: Set/allocated/freed by libavcodec.
1329 * - decoding: Set/allocated/freed by user.
1335 * This is the fundamental unit of time (in seconds) in terms
1336 * of which frame timestamps are represented. For fixed-fps content,
1337 * timebase should be 1/framerate and timestamp increments should be
1339 * - encoding: MUST be set by user.
1340 * - decoding: Set by libavcodec.
1342 AVRational time_base;
1345 * For some codecs, the time base is closer to the field rate than the frame rate.
1346 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1347 * if no telecine is used ...
1349 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1351 int ticks_per_frame;
1356 * Encoding: Number of frames delay there will be from the encoder input to
1357 * the decoder output. (we assume the decoder matches the spec)
1358 * Decoding: Number of frames delay in addition to what a standard decoder
1359 * as specified in the spec would produce.
1362 * Number of frames the decoded output will be delayed relative to the
1366 * For encoding, this is the number of "priming" samples added by the
1367 * encoder to the beginning of the stream. The decoded output will be
1368 * delayed by this many samples relative to the input to the encoder (or
1369 * more, if the decoder adds its own padding).
1370 * The timestamps on the output packets are adjusted by the encoder so
1371 * that they always refer to the first sample of the data actually
1372 * contained in the packet, including any added padding.
1373 * E.g. if the timebase is 1/samplerate and the timestamp of the first
1374 * input sample is 0, the timestamp of the first output packet will be
1377 * For decoding, this is the number of samples the decoder needs to
1378 * output before the decoder's output is valid. When seeking, you should
1379 * start decoding this many samples prior to your desired seek point.
1381 * - encoding: Set by libavcodec.
1382 * - decoding: Set by libavcodec.
1389 * picture width / height.
1390 * - encoding: MUST be set by user.
1391 * - decoding: May be set by the user before opening the decoder if known e.g.
1392 * from the container. Some decoders will require the dimensions
1393 * to be set by the caller. During decoding, the decoder may
1394 * overwrite those values as required.
1399 * Bitstream width / height, may be different from width/height e.g. when
1400 * the decoded frame is cropped before being output or lowres is enabled.
1401 * - encoding: unused
1402 * - decoding: May be set by the user before opening the decoder if known
1403 * e.g. from the container. During decoding, the decoder may
1404 * overwrite those values as required.
1406 int coded_width, coded_height;
1408 #if FF_API_ASPECT_EXTENDED
1409 #define FF_ASPECT_EXTENDED 15
1413 * the number of pictures in a group of pictures, or 0 for intra_only
1414 * - encoding: Set by user.
1415 * - decoding: unused
1420 * Pixel format, see AV_PIX_FMT_xxx.
1421 * May be set by the demuxer if known from headers.
1422 * May be overridden by the decoder if it knows better.
1423 * - encoding: Set by user.
1424 * - decoding: Set by user if known, overridden by libavcodec if known
1426 enum AVPixelFormat pix_fmt;
1429 * Motion estimation algorithm used for video coding.
1430 * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
1431 * 8 (umh), 9 (iter), 10 (tesa) [7, 8, 10 are x264 specific, 9 is snow specific]
1432 * - encoding: MUST be set by user.
1433 * - decoding: unused
1438 * If non NULL, 'draw_horiz_band' is called by the libavcodec
1439 * decoder to draw a horizontal band. It improves cache usage. Not
1440 * all codecs can do that. You must check the codec capabilities
1442 * When multithreading is used, it may be called from multiple threads
1443 * at the same time; threads might draw different parts of the same AVFrame,
1444 * or multiple AVFrames, and there is no guarantee that slices will be drawn
1446 * The function is also used by hardware acceleration APIs.
1447 * It is called at least once during frame decoding to pass
1448 * the data needed for hardware render.
1449 * In that mode instead of pixel data, AVFrame points to
1450 * a structure specific to the acceleration API. The application
1451 * reads the structure and can change some fields to indicate progress
1453 * - encoding: unused
1454 * - decoding: Set by user.
1455 * @param height the height of the slice
1456 * @param y the y position of the slice
1457 * @param type 1->top field, 2->bottom field, 3->frame
1458 * @param offset offset into the AVFrame.data from which the slice should be read
1460 void (*draw_horiz_band)(struct AVCodecContext *s,
1461 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1462 int y, int type, int height);
1465 * callback to negotiate the pixelFormat
1466 * @param fmt is the list of formats which are supported by the codec,
1467 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1468 * The first is always the native one.
1469 * @return the chosen format
1470 * - encoding: unused
1471 * - decoding: Set by user, if not set the native format will be chosen.
1473 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1476 * maximum number of B-frames between non-B-frames
1477 * Note: The output will be delayed by max_b_frames+1 relative to the input.
1478 * - encoding: Set by user.
1479 * - decoding: unused
1484 * qscale factor between IP and B-frames
1485 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1486 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1487 * - encoding: Set by user.
1488 * - decoding: unused
1490 float b_quant_factor;
1492 /** obsolete FIXME remove */
1494 #define FF_RC_STRATEGY_XVID 1
1496 int b_frame_strategy;
1499 * qscale offset between IP and B-frames
1500 * - encoding: Set by user.
1501 * - decoding: unused
1503 float b_quant_offset;
1506 * Size of the frame reordering buffer in the decoder.
1507 * For MPEG-2 it is 1 IPB or 0 low delay IP.
1508 * - encoding: Set by libavcodec.
1509 * - decoding: Set by libavcodec.
1514 * 0-> h263 quant 1-> mpeg quant
1515 * - encoding: Set by user.
1516 * - decoding: unused
1521 * qscale factor between P and I-frames
1522 * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
1523 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1524 * - encoding: Set by user.
1525 * - decoding: unused
1527 float i_quant_factor;
1530 * qscale offset between P and I-frames
1531 * - encoding: Set by user.
1532 * - decoding: unused
1534 float i_quant_offset;
1537 * luminance masking (0-> disabled)
1538 * - encoding: Set by user.
1539 * - decoding: unused
1544 * temporary complexity masking (0-> disabled)
1545 * - encoding: Set by user.
1546 * - decoding: unused
1548 float temporal_cplx_masking;
1551 * spatial complexity masking (0-> disabled)
1552 * - encoding: Set by user.
1553 * - decoding: unused
1555 float spatial_cplx_masking;
1558 * p block masking (0-> disabled)
1559 * - encoding: Set by user.
1560 * - decoding: unused
1565 * darkness masking (0-> disabled)
1566 * - encoding: Set by user.
1567 * - decoding: unused
1573 * - encoding: Set by libavcodec.
1574 * - decoding: Set by user (or 0).
1578 * prediction method (needed for huffyuv)
1579 * - encoding: Set by user.
1580 * - decoding: unused
1582 int prediction_method;
1583 #define FF_PRED_LEFT 0
1584 #define FF_PRED_PLANE 1
1585 #define FF_PRED_MEDIAN 2
1588 * slice offsets in the frame in bytes
1589 * - encoding: Set/allocated by libavcodec.
1590 * - decoding: Set/allocated by user (or NULL).
1595 * sample aspect ratio (0 if unknown)
1596 * That is the width of a pixel divided by the height of the pixel.
1597 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1598 * - encoding: Set by user.
1599 * - decoding: Set by libavcodec.
1601 AVRational sample_aspect_ratio;
1604 * motion estimation comparison function
1605 * - encoding: Set by user.
1606 * - decoding: unused
1610 * subpixel motion estimation comparison function
1611 * - encoding: Set by user.
1612 * - decoding: unused
1616 * macroblock comparison function (not supported yet)
1617 * - encoding: Set by user.
1618 * - decoding: unused
1622 * interlaced DCT comparison function
1623 * - encoding: Set by user.
1624 * - decoding: unused
1627 #define FF_CMP_SAD 0
1628 #define FF_CMP_SSE 1
1629 #define FF_CMP_SATD 2
1630 #define FF_CMP_DCT 3
1631 #define FF_CMP_PSNR 4
1632 #define FF_CMP_BIT 5
1634 #define FF_CMP_ZERO 7
1635 #define FF_CMP_VSAD 8
1636 #define FF_CMP_VSSE 9
1637 #define FF_CMP_NSSE 10
1638 #define FF_CMP_W53 11
1639 #define FF_CMP_W97 12
1640 #define FF_CMP_DCTMAX 13
1641 #define FF_CMP_DCT264 14
1642 #define FF_CMP_CHROMA 256
1645 * ME diamond size & shape
1646 * - encoding: Set by user.
1647 * - decoding: unused
1652 * amount of previous MV predictors (2a+1 x 2a+1 square)
1653 * - encoding: Set by user.
1654 * - decoding: unused
1656 int last_predictor_count;
1659 * prepass for motion estimation
1660 * - encoding: Set by user.
1661 * - decoding: unused
1666 * motion estimation prepass comparison function
1667 * - encoding: Set by user.
1668 * - decoding: unused
1673 * ME prepass diamond size & shape
1674 * - encoding: Set by user.
1675 * - decoding: unused
1681 * - encoding: Set by user.
1682 * - decoding: unused
1684 int me_subpel_quality;
1687 * DTG active format information (additional aspect ratio
1688 * information only used in DVB MPEG-2 transport streams)
1691 * - encoding: unused
1692 * - decoding: Set by decoder.
1694 int dtg_active_format;
1695 #define FF_DTG_AFD_SAME 8
1696 #define FF_DTG_AFD_4_3 9
1697 #define FF_DTG_AFD_16_9 10
1698 #define FF_DTG_AFD_14_9 11
1699 #define FF_DTG_AFD_4_3_SP_14_9 13
1700 #define FF_DTG_AFD_16_9_SP_14_9 14
1701 #define FF_DTG_AFD_SP_4_3 15
1704 * maximum motion estimation search range in subpel units
1705 * If 0 then no limit.
1707 * - encoding: Set by user.
1708 * - decoding: unused
1713 * intra quantizer bias
1714 * - encoding: Set by user.
1715 * - decoding: unused
1717 int intra_quant_bias;
1718 #define FF_DEFAULT_QUANT_BIAS 999999
1721 * inter quantizer bias
1722 * - encoding: Set by user.
1723 * - decoding: unused
1725 int inter_quant_bias;
1729 * - encoding: unused
1730 * - decoding: Set by user.
1733 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1734 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
1735 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1739 * XVideo Motion Acceleration
1740 * - encoding: forbidden
1741 * - decoding: set by decoder
1742 * @deprecated XvMC doesn't need it anymore.
1744 attribute_deprecated int xvmc_acceleration;
1745 #endif /* FF_API_XVMC */
1748 * macroblock decision mode
1749 * - encoding: Set by user.
1750 * - decoding: unused
1753 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1754 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1755 #define FF_MB_DECISION_RD 2 ///< rate distortion
1758 * custom intra quantization matrix
1759 * - encoding: Set by user, can be NULL.
1760 * - decoding: Set by libavcodec.
1762 uint16_t *intra_matrix;
1765 * custom inter quantization matrix
1766 * - encoding: Set by user, can be NULL.
1767 * - decoding: Set by libavcodec.
1769 uint16_t *inter_matrix;
1772 * scene change detection threshold
1773 * 0 is default, larger means fewer detected scene changes.
1774 * - encoding: Set by user.
1775 * - decoding: unused
1777 int scenechange_threshold;
1780 * noise reduction strength
1781 * - encoding: Set by user.
1782 * - decoding: unused
1784 int noise_reduction;
1787 * Motion estimation threshold below which no motion estimation is
1788 * performed, but instead the user specified motion vectors are used.
1790 * - encoding: Set by user.
1791 * - decoding: unused
1796 * Macroblock threshold below which the user specified macroblock types will be used.
1797 * - encoding: Set by user.
1798 * - decoding: unused
1803 * precision of the intra DC coefficient - 8
1804 * - encoding: Set by user.
1805 * - decoding: unused
1807 int intra_dc_precision;
1810 * Number of macroblock rows at the top which are skipped.
1811 * - encoding: unused
1812 * - decoding: Set by user.
1817 * Number of macroblock rows at the bottom which are skipped.
1818 * - encoding: unused
1819 * - decoding: Set by user.
1824 * Border processing masking, raises the quantizer for mbs on the borders
1826 * - encoding: Set by user.
1827 * - decoding: unused
1829 float border_masking;
1832 * minimum MB lagrange multipler
1833 * - encoding: Set by user.
1834 * - decoding: unused
1839 * maximum MB lagrange multipler
1840 * - encoding: Set by user.
1841 * - decoding: unused
1847 * - encoding: Set by user.
1848 * - decoding: unused
1850 int me_penalty_compensation;
1854 * - encoding: Set by user.
1855 * - decoding: unused
1861 * - encoding: Set by user.
1862 * - decoding: unused
1868 * - encoding: Set by user.
1869 * - decoding: unused
1874 * number of reference frames
1875 * - encoding: Set by user.
1876 * - decoding: Set by lavc.
1881 * chroma qp offset from luma
1882 * - encoding: Set by user.
1883 * - decoding: unused
1888 * Multiplied by qscale for each frame and added to scene_change_score.
1889 * - encoding: Set by user.
1890 * - decoding: unused
1892 int scenechange_factor;
1896 * Note: Value depends upon the compare function used for fullpel ME.
1897 * - encoding: Set by user.
1898 * - decoding: unused
1903 * Adjust sensitivity of b_frame_strategy 1.
1904 * - encoding: Set by user.
1905 * - decoding: unused
1910 * Chromaticity coordinates of the source primaries.
1911 * - encoding: Set by user
1912 * - decoding: Set by libavcodec
1914 enum AVColorPrimaries color_primaries;
1917 * Color Transfer Characteristic.
1918 * - encoding: Set by user
1919 * - decoding: Set by libavcodec
1921 enum AVColorTransferCharacteristic color_trc;
1924 * YUV colorspace type.
1925 * - encoding: Set by user
1926 * - decoding: Set by libavcodec
1928 enum AVColorSpace colorspace;
1931 * MPEG vs JPEG YUV range.
1932 * - encoding: Set by user
1933 * - decoding: Set by libavcodec
1935 enum AVColorRange color_range;
1938 * This defines the location of chroma samples.
1939 * - encoding: Set by user
1940 * - decoding: Set by libavcodec
1942 enum AVChromaLocation chroma_sample_location;
1946 * Indicates number of picture subdivisions. Used for parallelized
1948 * - encoding: Set by user
1949 * - decoding: unused
1954 * - encoding: set by libavcodec
1955 * - decoding: Set by user.
1957 enum AVFieldOrder field_order;
1960 int sample_rate; ///< samples per second
1961 int channels; ///< number of audio channels
1964 * audio sample format
1965 * - encoding: Set by user.
1966 * - decoding: Set by libavcodec.
1968 enum AVSampleFormat sample_fmt; ///< sample format
1970 /* The following data should not be initialized. */
1972 * Number of samples per channel in an audio frame.
1974 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1975 * except the last must contain exactly frame_size samples per channel.
1976 * May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1977 * frame size is not restricted.
1978 * - decoding: may be set by some decoders to indicate constant frame size
1983 * Frame counter, set by libavcodec.
1985 * - decoding: total number of frames returned from the decoder so far.
1986 * - encoding: total number of frames passed to the encoder so far.
1988 * @note the counter is not incremented if encoding/decoding resulted in
1994 * number of bytes per packet if constant and known or 0
1995 * Used by some WAV based audio codecs.
2000 * Audio cutoff bandwidth (0 means "automatic")
2001 * - encoding: Set by user.
2002 * - decoding: unused
2006 #if FF_API_REQUEST_CHANNELS
2008 * Decoder should decode to this many channels if it can (0 for default)
2009 * - encoding: unused
2010 * - decoding: Set by user.
2011 * @deprecated Deprecated in favor of request_channel_layout.
2013 attribute_deprecated int request_channels;
2017 * Audio channel layout.
2018 * - encoding: set by user.
2019 * - decoding: set by user, may be overwritten by libavcodec.
2021 uint64_t channel_layout;
2024 * Request decoder to use this channel layout if it can (0 for default)
2025 * - encoding: unused
2026 * - decoding: Set by user.
2028 uint64_t request_channel_layout;
2031 * Type of service that the audio stream conveys.
2032 * - encoding: Set by user.
2033 * - decoding: Set by libavcodec.
2035 enum AVAudioServiceType audio_service_type;
2038 * desired sample format
2039 * - encoding: Not used.
2040 * - decoding: Set by user.
2041 * Decoder will decode to this format if it can.
2043 enum AVSampleFormat request_sample_fmt;
2045 #if FF_API_GET_BUFFER
2047 * Called at the beginning of each frame to get a buffer for it.
2049 * The function will set AVFrame.data[], AVFrame.linesize[].
2050 * AVFrame.extended_data[] must also be set, but it should be the same as
2051 * AVFrame.data[] except for planar audio with more channels than can fit
2052 * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
2053 * many data pointers as it can hold.
2055 * if CODEC_CAP_DR1 is not set then get_buffer() must call
2056 * avcodec_default_get_buffer() instead of providing buffers allocated by
2059 * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
2060 * need it. avcodec_default_get_buffer() aligns the output buffer properly,
2061 * but if get_buffer() is overridden then alignment considerations should
2062 * be taken into account.
2064 * @see avcodec_default_get_buffer()
2068 * If pic.reference is set then the frame will be read later by libavcodec.
2069 * avcodec_align_dimensions2() should be used to find the required width and
2070 * height, as they normally need to be rounded up to the next multiple of 16.
2072 * If frame multithreading is used and thread_safe_callbacks is set,
2073 * it may be called from a different thread, but not from more than one at
2074 * once. Does not need to be reentrant.
2076 * @see release_buffer(), reget_buffer()
2077 * @see avcodec_align_dimensions2()
2081 * Decoders request a buffer of a particular size by setting
2082 * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
2083 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2084 * to a smaller value in the output frame.
2086 * Decoders cannot use the buffer after returning from
2087 * avcodec_decode_audio4(), so they will not call release_buffer(), as it
2088 * is assumed to be released immediately upon return. In some rare cases,
2089 * a decoder may need to call get_buffer() more than once in a single
2090 * call to avcodec_decode_audio4(). In that case, when get_buffer() is
2091 * called again after it has already been called once, the previously
2092 * acquired buffer is assumed to be released at that time and may not be
2093 * reused by the decoder.
2095 * As a convenience, av_samples_get_buffer_size() and
2096 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
2097 * functions to find the required data size and to fill data pointers and
2098 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2099 * since all planes must be the same size.
2101 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2103 * - encoding: unused
2104 * - decoding: Set by libavcodec, user can override.
2106 * @deprecated use get_buffer2()
2108 attribute_deprecated
2109 int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
2112 * Called to release buffers which were allocated with get_buffer.
2113 * A released buffer can be reused in get_buffer().
2114 * pic.data[*] must be set to NULL.
2115 * May be called from a different thread if frame multithreading is used,
2116 * but not by more than one thread at once, so does not need to be reentrant.
2117 * - encoding: unused
2118 * - decoding: Set by libavcodec, user can override.
2120 * @deprecated custom freeing callbacks should be set from get_buffer2()
2122 attribute_deprecated
2123 void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
2126 * Called at the beginning of a frame to get cr buffer for it.
2127 * Buffer type (size, hints) must be the same. libavcodec won't check it.
2128 * libavcodec will pass previous buffer in pic, function should return
2129 * same buffer or new buffer with old frame "painted" into it.
2130 * If pic.data[0] == NULL must behave like get_buffer().
2131 * if CODEC_CAP_DR1 is not set then reget_buffer() must call
2132 * avcodec_default_reget_buffer() instead of providing buffers allocated by
2134 * - encoding: unused
2135 * - decoding: Set by libavcodec, user can override.
2137 attribute_deprecated
2138 int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
2142 * This callback is called at the beginning of each frame to get data
2143 * buffer(s) for it. There may be one contiguous buffer for all the data or
2144 * there may be a buffer per each data plane or anything in between. What
2145 * this means is, you may set however many entries in buf[] you feel necessary.
2146 * Each buffer must be reference-counted using the AVBuffer API (see description
2149 * The following fields will be set in the frame before this callback is
2152 * - width, height (video only)
2153 * - sample_rate, channel_layout, nb_samples (audio only)
2154 * Their values may differ from the corresponding values in
2155 * AVCodecContext. This callback must use the frame values, not the codec
2156 * context values, to calculate the required buffer size.
2158 * This callback must fill the following fields in the frame:
2162 * * if the data is planar audio with more than 8 channels, then this
2163 * callback must allocate and fill extended_data to contain all pointers
2164 * to all data planes. data[] must hold as many pointers as it can.
2165 * extended_data must be allocated with av_malloc() and will be freed in
2167 * * otherwise exended_data must point to data
2168 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2169 * the frame's data and extended_data pointers must be contained in these. That
2170 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2171 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2172 * and av_buffer_ref().
2173 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2174 * this callback and filled with the extra buffers if there are more
2175 * buffers than buf[] can hold. extended_buf will be freed in
2178 * If CODEC_CAP_DR1 is not set then get_buffer2() must call
2179 * avcodec_default_get_buffer2() instead of providing buffers allocated by
2182 * Each data plane must be aligned to the maximum required by the target
2185 * @see avcodec_default_get_buffer2()
2189 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2190 * (read and/or written to if it is writable) later by libavcodec.
2192 * avcodec_align_dimensions2() should be used to find the required width and
2193 * height, as they normally need to be rounded up to the next multiple of 16.
2195 * Some decoders do not support linesizes changing between frames.
2197 * If frame multithreading is used and thread_safe_callbacks is set,
2198 * this callback may be called from a different thread, but not from more
2199 * than one at once. Does not need to be reentrant.
2201 * @see avcodec_align_dimensions2()
2205 * Decoders request a buffer of a particular size by setting
2206 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2207 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2208 * to a smaller value in the output frame.
2210 * As a convenience, av_samples_get_buffer_size() and
2211 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2212 * functions to find the required data size and to fill data pointers and
2213 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2214 * since all planes must be the same size.
2216 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2218 * - encoding: unused
2219 * - decoding: Set by libavcodec, user can override.
2221 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2224 * If non-zero, the decoded audio and video frames returned from
2225 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2226 * and are valid indefinitely. The caller must free them with
2227 * av_frame_unref() when they are not needed anymore.
2228 * Otherwise, the decoded frames must not be freed by the caller and are
2229 * only valid until the next decode call.
2231 * - encoding: unused
2232 * - decoding: set by the caller before avcodec_open2().
2234 int refcounted_frames;
2236 /* - encoding parameters */
2237 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2238 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2242 * - encoding: Set by user.
2243 * - decoding: unused
2249 * - encoding: Set by user.
2250 * - decoding: unused
2255 * maximum quantizer difference between frames
2256 * - encoding: Set by user.
2257 * - decoding: unused
2262 * ratecontrol qmin qmax limiting method
2263 * 0-> clipping, 1-> use a nice continuous function to limit qscale within qmin/qmax.
2264 * - encoding: Set by user.
2265 * - decoding: unused
2273 * decoder bitstream buffer size
2274 * - encoding: Set by user.
2275 * - decoding: unused
2280 * ratecontrol override, see RcOverride
2281 * - encoding: Allocated/set/freed by user.
2282 * - decoding: unused
2284 int rc_override_count;
2285 RcOverride *rc_override;
2288 * rate control equation
2289 * - encoding: Set by user
2290 * - decoding: unused
2296 * - encoding: Set by user.
2297 * - decoding: unused
2303 * - encoding: Set by user.
2304 * - decoding: unused
2308 float rc_buffer_aggressivity;
2311 * initial complexity for pass1 ratecontrol
2312 * - encoding: Set by user.
2313 * - decoding: unused
2315 float rc_initial_cplx;
2318 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2319 * - encoding: Set by user.
2320 * - decoding: unused.
2322 float rc_max_available_vbv_use;
2325 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2326 * - encoding: Set by user.
2327 * - decoding: unused.
2329 float rc_min_vbv_overflow_use;
2332 * Number of bits which should be loaded into the rc buffer before decoding starts.
2333 * - encoding: Set by user.
2334 * - decoding: unused
2336 int rc_initial_buffer_occupancy;
2338 #define FF_CODER_TYPE_VLC 0
2339 #define FF_CODER_TYPE_AC 1
2340 #define FF_CODER_TYPE_RAW 2
2341 #define FF_CODER_TYPE_RLE 3
2342 #define FF_CODER_TYPE_DEFLATE 4
2345 * - encoding: Set by user.
2346 * - decoding: unused
2352 * - encoding: Set by user.
2353 * - decoding: unused
2358 * minimum Lagrange multiplier
2359 * - encoding: Set by user.
2360 * - decoding: unused
2365 * maximum Lagrange multiplier
2366 * - encoding: Set by user.
2367 * - decoding: unused
2372 * frame skip threshold
2373 * - encoding: Set by user.
2374 * - decoding: unused
2376 int frame_skip_threshold;
2380 * - encoding: Set by user.
2381 * - decoding: unused
2383 int frame_skip_factor;
2386 * frame skip exponent
2387 * - encoding: Set by user.
2388 * - decoding: unused
2393 * frame skip comparison function
2394 * - encoding: Set by user.
2395 * - decoding: unused
2400 * trellis RD quantization
2401 * - encoding: Set by user.
2402 * - decoding: unused
2407 * - encoding: Set by user.
2408 * - decoding: unused
2410 int min_prediction_order;
2413 * - encoding: Set by user.
2414 * - decoding: unused
2416 int max_prediction_order;
2419 * GOP timecode frame start number
2420 * - encoding: Set by user, in non drop frame format
2421 * - decoding: Set by libavcodec (timecode in the 25 bits format, -1 if unset)
2423 int64_t timecode_frame_start;
2425 /* The RTP callback: This function is called */
2426 /* every time the encoder has a packet to send. */
2427 /* It depends on the encoder if the data starts */
2428 /* with a Start Code (it should). H.263 does. */
2429 /* mb_nb contains the number of macroblocks */
2430 /* encoded in the RTP payload. */
2431 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2433 int rtp_payload_size; /* The size of the RTP payload: the coder will */
2434 /* do its best to deliver a chunk with size */
2435 /* below rtp_payload_size, the chunk will start */
2436 /* with a start code on some codecs like H.263. */
2437 /* This doesn't take account of any particular */
2438 /* headers inside the transmitted RTP payload. */
2440 /* statistics, used for 2-pass encoding */
2451 * number of bits used for the previously encoded frame
2452 * - encoding: Set by libavcodec.
2453 * - decoding: unused
2458 * pass1 encoding statistics output buffer
2459 * - encoding: Set by libavcodec.
2460 * - decoding: unused
2465 * pass2 encoding statistics input buffer
2466 * Concatenated stuff from stats_out of pass1 should be placed here.
2467 * - encoding: Allocated/set/freed by user.
2468 * - decoding: unused
2473 * Work around bugs in encoders which sometimes cannot be detected automatically.
2474 * - encoding: Set by user
2475 * - decoding: Set by user
2477 int workaround_bugs;
2478 #define FF_BUG_AUTODETECT 1 ///< autodetection
2479 #if FF_API_OLD_MSMPEG4
2480 #define FF_BUG_OLD_MSMPEG4 2
2482 #define FF_BUG_XVID_ILACE 4
2483 #define FF_BUG_UMP4 8
2484 #define FF_BUG_NO_PADDING 16
2485 #define FF_BUG_AMV 32
2487 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2489 #define FF_BUG_QPEL_CHROMA 64
2490 #define FF_BUG_STD_QPEL 128
2491 #define FF_BUG_QPEL_CHROMA2 256
2492 #define FF_BUG_DIRECT_BLOCKSIZE 512
2493 #define FF_BUG_EDGE 1024
2494 #define FF_BUG_HPEL_CHROMA 2048
2495 #define FF_BUG_DC_CLIP 4096
2496 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2497 #define FF_BUG_TRUNCATED 16384
2500 * strictly follow the standard (MPEG4, ...).
2501 * - encoding: Set by user.
2502 * - decoding: Set by user.
2503 * Setting this to STRICT or higher means the encoder and decoder will
2504 * generally do stupid things, whereas setting it to unofficial or lower
2505 * will mean the encoder might produce output that is not supported by all
2506 * spec-compliant decoders. Decoders don't differentiate between normal,
2507 * unofficial and experimental (that is, they always try to decode things
2508 * when they can) unless they are explicitly asked to behave stupidly
2509 * (=strictly conform to the specs)
2511 int strict_std_compliance;
2512 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2513 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2514 #define FF_COMPLIANCE_NORMAL 0
2515 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2516 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2519 * error concealment flags
2520 * - encoding: unused
2521 * - decoding: Set by user.
2523 int error_concealment;
2524 #define FF_EC_GUESS_MVS 1
2525 #define FF_EC_DEBLOCK 2
2529 * - encoding: Set by user.
2530 * - decoding: Set by user.
2533 #define FF_DEBUG_PICT_INFO 1
2534 #define FF_DEBUG_RC 2
2535 #define FF_DEBUG_BITSTREAM 4
2536 #define FF_DEBUG_MB_TYPE 8
2537 #define FF_DEBUG_QP 16
2540 * @deprecated this option does nothing
2542 #define FF_DEBUG_MV 32
2544 #define FF_DEBUG_DCT_COEFF 0x00000040
2545 #define FF_DEBUG_SKIP 0x00000080
2546 #define FF_DEBUG_STARTCODE 0x00000100
2547 #define FF_DEBUG_PTS 0x00000200
2548 #define FF_DEBUG_ER 0x00000400
2549 #define FF_DEBUG_MMCO 0x00000800
2550 #define FF_DEBUG_BUGS 0x00001000
2552 #define FF_DEBUG_VIS_QP 0x00002000 ///< only access through AVOptions from outside libavcodec
2553 #define FF_DEBUG_VIS_MB_TYPE 0x00004000 ///< only access through AVOptions from outside libavcodec
2555 #define FF_DEBUG_BUFFERS 0x00008000
2556 #define FF_DEBUG_THREADS 0x00010000
2561 * Code outside libavcodec should access this field using AVOptions
2562 * - encoding: Set by user.
2563 * - decoding: Set by user.
2566 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2567 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2568 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2572 * Error recognition; may misdetect some more or less valid parts as errors.
2573 * - encoding: unused
2574 * - decoding: Set by user.
2576 int err_recognition;
2579 * Verify checksums embedded in the bitstream (could be of either encoded or
2580 * decoded data, depending on the codec) and print an error message on mismatch.
2581 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2582 * decoder returning an error.
2584 #define AV_EF_CRCCHECK (1<<0)
2585 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2586 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2587 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2589 #define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
2590 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2591 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2595 * opaque 64bit number (generally a PTS) that will be reordered and
2596 * output in AVFrame.reordered_opaque
2597 * @deprecated in favor of pkt_pts
2598 * - encoding: unused
2599 * - decoding: Set by user.
2601 int64_t reordered_opaque;
2604 * Hardware accelerator in use
2605 * - encoding: unused.
2606 * - decoding: Set by libavcodec
2608 struct AVHWAccel *hwaccel;
2611 * Hardware accelerator context.
2612 * For some hardware accelerators, a global context needs to be
2613 * provided by the user. In that case, this holds display-dependent
2614 * data FFmpeg cannot instantiate itself. Please refer to the
2615 * FFmpeg HW accelerator documentation to know how to fill this
2616 * is. e.g. for VA API, this is a struct vaapi_context.
2617 * - encoding: unused
2618 * - decoding: Set by user
2620 void *hwaccel_context;
2624 * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
2625 * - decoding: unused
2627 uint64_t error[AV_NUM_DATA_POINTERS];
2630 * DCT algorithm, see FF_DCT_* below
2631 * - encoding: Set by user.
2632 * - decoding: unused
2635 #define FF_DCT_AUTO 0
2636 #define FF_DCT_FASTINT 1
2637 #define FF_DCT_INT 2
2638 #define FF_DCT_MMX 3
2639 #define FF_DCT_ALTIVEC 5
2640 #define FF_DCT_FAAN 6
2643 * IDCT algorithm, see FF_IDCT_* below.
2644 * - encoding: Set by user.
2645 * - decoding: Set by user.
2648 #define FF_IDCT_AUTO 0
2649 #define FF_IDCT_INT 1
2650 #define FF_IDCT_SIMPLE 2
2651 #define FF_IDCT_SIMPLEMMX 3
2652 #define FF_IDCT_ARM 7
2653 #define FF_IDCT_ALTIVEC 8
2655 #define FF_IDCT_SH4 9
2657 #define FF_IDCT_SIMPLEARM 10
2658 #define FF_IDCT_IPP 13
2659 #define FF_IDCT_XVIDMMX 14
2660 #define FF_IDCT_SIMPLEARMV5TE 16
2661 #define FF_IDCT_SIMPLEARMV6 17
2662 #if FF_API_ARCH_SPARC
2663 #define FF_IDCT_SIMPLEVIS 18
2665 #define FF_IDCT_FAAN 20
2666 #define FF_IDCT_SIMPLENEON 22
2667 #if FF_API_ARCH_ALPHA
2668 #define FF_IDCT_SIMPLEALPHA 23
2672 * bits per sample/pixel from the demuxer (needed for huffyuv).
2673 * - encoding: Set by libavcodec.
2674 * - decoding: Set by user.
2676 int bits_per_coded_sample;
2679 * Bits per sample/pixel of internal libavcodec pixel/sample format.
2680 * - encoding: set by user.
2681 * - decoding: set by libavcodec.
2683 int bits_per_raw_sample;
2687 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2688 * - encoding: unused
2689 * - decoding: Set by user.
2690 * Code outside libavcodec should access this field using:
2691 * av_codec_{get,set}_lowres(avctx)
2697 * the picture in the bitstream
2698 * - encoding: Set by libavcodec.
2699 * - decoding: unused
2701 AVFrame *coded_frame;
2705 * is used to decide how many independent tasks should be passed to execute()
2706 * - encoding: Set by user.
2707 * - decoding: Set by user.
2712 * Which multithreading methods to use.
2713 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2714 * so clients which cannot provide future frames should not use it.
2716 * - encoding: Set by user, otherwise the default is used.
2717 * - decoding: Set by user, otherwise the default is used.
2720 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2721 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2724 * Which multithreading methods are in use by the codec.
2725 * - encoding: Set by libavcodec.
2726 * - decoding: Set by libavcodec.
2728 int active_thread_type;
2731 * Set by the client if its custom get_buffer() callback can be called
2732 * synchronously from another thread, which allows faster multithreaded decoding.
2733 * draw_horiz_band() will be called from other threads regardless of this setting.
2734 * Ignored if the default get_buffer() is used.
2735 * - encoding: Set by user.
2736 * - decoding: Set by user.
2738 int thread_safe_callbacks;
2741 * The codec may call this to execute several independent things.
2742 * It will return only after finishing all tasks.
2743 * The user may replace this with some multithreaded implementation,
2744 * the default implementation will execute the parts serially.
2745 * @param count the number of things to execute
2746 * - encoding: Set by libavcodec, user can override.
2747 * - decoding: Set by libavcodec, user can override.
2749 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2752 * The codec may call this to execute several independent things.
2753 * It will return only after finishing all tasks.
2754 * The user may replace this with some multithreaded implementation,
2755 * the default implementation will execute the parts serially.
2756 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2757 * @param c context passed also to func
2758 * @param count the number of things to execute
2759 * @param arg2 argument passed unchanged to func
2760 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2761 * @param func function that will be called count times, with jobnr from 0 to count-1.
2762 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2763 * two instances of func executing at the same time will have the same threadnr.
2764 * @return always 0 currently, but code should handle a future improvement where when any call to func
2765 * returns < 0 no further calls to func may be done and < 0 is returned.
2766 * - encoding: Set by libavcodec, user can override.
2767 * - decoding: Set by libavcodec, user can override.
2769 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2771 #if FF_API_THREAD_OPAQUE
2773 * @deprecated this field should not be used from outside of lavc
2775 attribute_deprecated
2776 void *thread_opaque;
2780 * noise vs. sse weight for the nsse comparison function
2781 * - encoding: Set by user.
2782 * - decoding: unused
2788 * - encoding: Set by user.
2789 * - decoding: Set by libavcodec.
2792 #define FF_PROFILE_UNKNOWN -99
2793 #define FF_PROFILE_RESERVED -100
2795 #define FF_PROFILE_AAC_MAIN 0
2796 #define FF_PROFILE_AAC_LOW 1
2797 #define FF_PROFILE_AAC_SSR 2
2798 #define FF_PROFILE_AAC_LTP 3
2799 #define FF_PROFILE_AAC_HE 4
2800 #define FF_PROFILE_AAC_HE_V2 28
2801 #define FF_PROFILE_AAC_LD 22
2802 #define FF_PROFILE_AAC_ELD 38
2803 #define FF_PROFILE_MPEG2_AAC_LOW 128
2804 #define FF_PROFILE_MPEG2_AAC_HE 131
2806 #define FF_PROFILE_DTS 20
2807 #define FF_PROFILE_DTS_ES 30
2808 #define FF_PROFILE_DTS_96_24 40
2809 #define FF_PROFILE_DTS_HD_HRA 50
2810 #define FF_PROFILE_DTS_HD_MA 60
2812 #define FF_PROFILE_MPEG2_422 0
2813 #define FF_PROFILE_MPEG2_HIGH 1
2814 #define FF_PROFILE_MPEG2_SS 2
2815 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2816 #define FF_PROFILE_MPEG2_MAIN 4
2817 #define FF_PROFILE_MPEG2_SIMPLE 5
2819 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2820 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2822 #define FF_PROFILE_H264_BASELINE 66
2823 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2824 #define FF_PROFILE_H264_MAIN 77
2825 #define FF_PROFILE_H264_EXTENDED 88
2826 #define FF_PROFILE_H264_HIGH 100
2827 #define FF_PROFILE_H264_HIGH_10 110
2828 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2829 #define FF_PROFILE_H264_HIGH_422 122
2830 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2831 #define FF_PROFILE_H264_HIGH_444 144
2832 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2833 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2834 #define FF_PROFILE_H264_CAVLC_444 44
2836 #define FF_PROFILE_VC1_SIMPLE 0
2837 #define FF_PROFILE_VC1_MAIN 1
2838 #define FF_PROFILE_VC1_COMPLEX 2
2839 #define FF_PROFILE_VC1_ADVANCED 3
2841 #define FF_PROFILE_MPEG4_SIMPLE 0
2842 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2843 #define FF_PROFILE_MPEG4_CORE 2
2844 #define FF_PROFILE_MPEG4_MAIN 3
2845 #define FF_PROFILE_MPEG4_N_BIT 4
2846 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2847 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2848 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2849 #define FF_PROFILE_MPEG4_HYBRID 8
2850 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2851 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2852 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2853 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2854 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2855 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2856 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2858 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 0
2859 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 1
2860 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 2
2861 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2862 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2865 #define FF_PROFILE_HEVC_MAIN 1
2866 #define FF_PROFILE_HEVC_MAIN_10 2
2867 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2871 * - encoding: Set by user.
2872 * - decoding: Set by libavcodec.
2875 #define FF_LEVEL_UNKNOWN -99
2878 * Skip loop filtering for selected frames.
2879 * - encoding: unused
2880 * - decoding: Set by user.
2882 enum AVDiscard skip_loop_filter;
2885 * Skip IDCT/dequantization for selected frames.
2886 * - encoding: unused
2887 * - decoding: Set by user.
2889 enum AVDiscard skip_idct;
2892 * Skip decoding for selected frames.
2893 * - encoding: unused
2894 * - decoding: Set by user.
2896 enum AVDiscard skip_frame;
2899 * Header containing style information for text subtitles.
2900 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2901 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2902 * the Format line following. It shouldn't include any Dialogue line.
2903 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2904 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2906 uint8_t *subtitle_header;
2907 int subtitle_header_size;
2909 #if FF_API_ERROR_RATE
2911 * @deprecated use the 'error_rate' private AVOption of the mpegvideo
2914 attribute_deprecated
2918 #if FF_API_CODEC_PKT
2920 * @deprecated this field is not supposed to be accessed from outside lavc
2922 attribute_deprecated
2927 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2928 * Used for compliant TS muxing.
2929 * - encoding: Set by libavcodec.
2930 * - decoding: unused.
2935 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2936 * Code outside libavcodec should access this field using:
2937 * av_codec_{get,set}_pkt_timebase(avctx)
2938 * - encoding unused.
2939 * - decoding set by user.
2941 AVRational pkt_timebase;
2945 * Code outside libavcodec should access this field using:
2946 * av_codec_{get,set}_codec_descriptor(avctx)
2947 * - encoding: unused.
2948 * - decoding: set by libavcodec.
2950 const AVCodecDescriptor *codec_descriptor;
2954 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2955 * - encoding: unused
2956 * - decoding: Set by user.
2957 * Code outside libavcodec should access this field using:
2958 * av_codec_{get,set}_lowres(avctx)
2964 * Current statistics for PTS correction.
2965 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
2966 * - encoding: unused
2968 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
2969 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
2970 int64_t pts_correction_last_pts; /// PTS of the last frame
2971 int64_t pts_correction_last_dts; /// DTS of the last frame
2974 * Character encoding of the input subtitles file.
2975 * - decoding: set by user
2976 * - encoding: unused
2981 * Subtitles character encoding mode. Formats or codecs might be adjusting
2982 * this setting (if they are doing the conversion themselves for instance).
2983 * - decoding: set by libavcodec
2984 * - encoding: unused
2986 int sub_charenc_mode;
2987 #define FF_SUB_CHARENC_MODE_DO_NOTHING -1 ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
2988 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
2989 #define FF_SUB_CHARENC_MODE_PRE_DECODER 1 ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
2992 * Skip processing alpha if supported by codec.
2993 * Note that if the format uses pre-multiplied alpha (common with VP6,
2994 * and recommended due to better video quality/compression)
2995 * the image will look as if alpha-blended onto a black background.
2996 * However for formats that do not use pre-multiplied alpha
2997 * there might be serious artefacts (though e.g. libswscale currently
2998 * assumes pre-multiplied alpha anyway).
2999 * Code outside libavcodec should access this field using AVOptions
3001 * - decoding: set by user
3002 * - encoding: unused
3007 * Number of samples to skip after a discontinuity
3008 * - decoding: unused
3009 * - encoding: set by libavcodec
3013 #if !FF_API_DEBUG_MV
3015 * debug motion vectors
3016 * Code outside libavcodec should access this field using AVOptions
3017 * - encoding: Set by user.
3018 * - decoding: Set by user.
3021 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3022 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3023 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3027 * custom intra quantization matrix
3028 * Code outside libavcodec should access this field using av_codec_g/set_chroma_intra_matrix()
3029 * - encoding: Set by user, can be NULL.
3030 * - decoding: unused.
3032 uint16_t *chroma_intra_matrix;
3035 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
3036 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
3038 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
3039 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
3041 int av_codec_get_lowres(const AVCodecContext *avctx);
3042 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3044 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3045 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3047 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3048 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3053 typedef struct AVProfile {
3055 const char *name; ///< short name for the profile
3058 typedef struct AVCodecDefault AVCodecDefault;
3065 typedef struct AVCodec {
3067 * Name of the codec implementation.
3068 * The name is globally unique among encoders and among decoders (but an
3069 * encoder and a decoder can share the same name).
3070 * This is the primary way to find a codec from the user perspective.
3074 * Descriptive name for the codec, meant to be more human readable than name.
3075 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3077 const char *long_name;
3078 enum AVMediaType type;
3081 * Codec capabilities.
3085 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3086 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3087 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3088 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3089 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3091 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder, no direct access, use av_codec_get_max_lowres()
3093 const AVClass *priv_class; ///< AVClass for the private context
3094 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3096 /*****************************************************************
3097 * No fields below this line are part of the public API. They
3098 * may not be used outside of libavcodec and can be changed and
3100 * New public fields should be added right above.
3101 *****************************************************************
3104 struct AVCodec *next;
3106 * @name Frame-level threading support functions
3110 * If defined, called on thread contexts when they are created.
3111 * If the codec allocates writable tables in init(), re-allocate them here.
3112 * priv_data will be set to a copy of the original.
3114 int (*init_thread_copy)(AVCodecContext *);
3116 * Copy necessary context variables from a previous thread context to the current one.
3117 * If not defined, the next thread will start automatically; otherwise, the codec
3118 * must call ff_thread_finish_setup().
3120 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3122 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
3126 * Private codec-specific defaults.
3128 const AVCodecDefault *defaults;
3131 * Initialize codec static data, called from avcodec_register().
3133 void (*init_static_data)(struct AVCodec *codec);
3135 int (*init)(AVCodecContext *);
3136 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3137 const struct AVSubtitle *sub);
3139 * Encode data to an AVPacket.
3141 * @param avctx codec context
3142 * @param avpkt output AVPacket (may contain a user-provided buffer)
3143 * @param[in] frame AVFrame containing the raw data to be encoded
3144 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3145 * non-empty packet was returned in avpkt.
3146 * @return 0 on success, negative error code on failure
3148 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3149 int *got_packet_ptr);
3150 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3151 int (*close)(AVCodecContext *);
3154 * Will be called when seeking
3156 void (*flush)(AVCodecContext *);
3159 int av_codec_get_max_lowres(const AVCodec *codec);
3161 struct MpegEncContext;
3166 typedef struct AVHWAccel {
3168 * Name of the hardware accelerated codec.
3169 * The name is globally unique among encoders and among decoders (but an
3170 * encoder and a decoder can share the same name).
3175 * Type of codec implemented by the hardware accelerator.
3177 * See AVMEDIA_TYPE_xxx
3179 enum AVMediaType type;
3182 * Codec implemented by the hardware accelerator.
3184 * See AV_CODEC_ID_xxx
3189 * Supported pixel format.
3191 * Only hardware accelerated formats are supported here.
3193 enum AVPixelFormat pix_fmt;
3196 * Hardware accelerated codec capabilities.
3197 * see FF_HWACCEL_CODEC_CAP_*
3201 struct AVHWAccel *next;
3204 * Called at the beginning of each frame or field picture.
3206 * Meaningful frame information (codec specific) is guaranteed to
3207 * be parsed at this point. This function is mandatory.
3209 * Note that buf can be NULL along with buf_size set to 0.
3210 * Otherwise, this means the whole frame is available at this point.
3212 * @param avctx the codec context
3213 * @param buf the frame data buffer base
3214 * @param buf_size the size of the frame in bytes
3215 * @return zero if successful, a negative value otherwise
3217 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3220 * Callback for each slice.
3222 * Meaningful slice information (codec specific) is guaranteed to
3223 * be parsed at this point. This function is mandatory.
3224 * The only exception is XvMC, that works on MB level.
3226 * @param avctx the codec context
3227 * @param buf the slice data buffer base
3228 * @param buf_size the size of the slice in bytes
3229 * @return zero if successful, a negative value otherwise
3231 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3234 * Called at the end of each frame or field picture.
3236 * The whole picture is parsed at this point and can now be sent
3237 * to the hardware accelerator. This function is mandatory.
3239 * @param avctx the codec context
3240 * @return zero if successful, a negative value otherwise
3242 int (*end_frame)(AVCodecContext *avctx);
3245 * Size of HW accelerator private data.
3247 * Private data is allocated with av_mallocz() before
3248 * AVCodecContext.get_buffer() and deallocated after
3249 * AVCodecContext.release_buffer().
3254 * Called for every Macroblock in a slice.
3256 * XvMC uses it to replace the ff_MPV_decode_mb().
3257 * Instead of decoding to raw picture, MB parameters are
3258 * stored in an array provided by the video driver.
3260 * @param s the mpeg context
3262 void (*decode_mb)(struct MpegEncContext *s);
3266 * @defgroup lavc_picture AVPicture
3268 * Functions for working with AVPicture
3273 * Picture data structure.
3275 * Up to four components can be stored into it, the last component is
3278 typedef struct AVPicture {
3279 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3280 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3287 enum AVSubtitleType {
3290 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3293 * Plain text, the text field must be set by the decoder and is
3294 * authoritative. ass and pict fields may contain approximations.
3299 * Formatted text, the ass field must be set by the decoder and is
3300 * authoritative. pict and text fields may contain approximations.
3305 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3307 typedef struct AVSubtitleRect {
3308 int x; ///< top left corner of pict, undefined when pict is not set
3309 int y; ///< top left corner of pict, undefined when pict is not set
3310 int w; ///< width of pict, undefined when pict is not set
3311 int h; ///< height of pict, undefined when pict is not set
3312 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3315 * data+linesize for the bitmap of this subtitle.
3316 * can be set for text/ass as well once they where rendered
3319 enum AVSubtitleType type;
3321 char *text; ///< 0 terminated plain UTF-8 text
3324 * 0 terminated ASS/SSA compatible event line.
3325 * The presentation of this is unaffected by the other values in this
3333 typedef struct AVSubtitle {
3334 uint16_t format; /* 0 = graphics */
3335 uint32_t start_display_time; /* relative to packet pts, in ms */
3336 uint32_t end_display_time; /* relative to packet pts, in ms */
3338 AVSubtitleRect **rects;
3339 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3343 * If c is NULL, returns the first registered codec,
3344 * if c is non-NULL, returns the next registered codec after c,
3345 * or NULL if c is the last one.
3347 AVCodec *av_codec_next(const AVCodec *c);
3350 * Return the LIBAVCODEC_VERSION_INT constant.
3352 unsigned avcodec_version(void);
3355 * Return the libavcodec build-time configuration.
3357 const char *avcodec_configuration(void);
3360 * Return the libavcodec license.
3362 const char *avcodec_license(void);
3365 * Register the codec codec and initialize libavcodec.
3367 * @warning either this function or avcodec_register_all() must be called
3368 * before any other libavcodec functions.
3370 * @see avcodec_register_all()
3372 void avcodec_register(AVCodec *codec);
3375 * Register all the codecs, parsers and bitstream filters which were enabled at
3376 * configuration time. If you do not call this function you can select exactly
3377 * which formats you want to support, by using the individual registration
3380 * @see avcodec_register
3381 * @see av_register_codec_parser
3382 * @see av_register_bitstream_filter
3384 void avcodec_register_all(void);
3387 * Allocate an AVCodecContext and set its fields to default values. The
3388 * resulting struct can be deallocated by calling avcodec_close() on it followed
3391 * @param codec if non-NULL, allocate private data and initialize defaults
3392 * for the given codec. It is illegal to then call avcodec_open2()
3393 * with a different codec.
3394 * If NULL, then the codec-specific defaults won't be initialized,
3395 * which may result in suboptimal default settings (this is
3396 * important mainly for encoders, e.g. libx264).
3398 * @return An AVCodecContext filled with default values or NULL on failure.
3399 * @see avcodec_get_context_defaults
3401 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3404 * Set the fields of the given AVCodecContext to default values corresponding
3405 * to the given codec (defaults may be codec-dependent).
3407 * Do not call this function if a non-NULL codec has been passed
3408 * to avcodec_alloc_context3() that allocated this AVCodecContext.
3409 * If codec is non-NULL, it is illegal to call avcodec_open2() with a
3410 * different codec on this AVCodecContext.
3412 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3415 * Get the AVClass for AVCodecContext. It can be used in combination with
3416 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3418 * @see av_opt_find().
3420 const AVClass *avcodec_get_class(void);
3423 * Get the AVClass for AVFrame. It can be used in combination with
3424 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3426 * @see av_opt_find().
3428 const AVClass *avcodec_get_frame_class(void);
3431 * Get the AVClass for AVSubtitleRect. It can be used in combination with
3432 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3434 * @see av_opt_find().
3436 const AVClass *avcodec_get_subtitle_rect_class(void);
3439 * Copy the settings of the source AVCodecContext into the destination
3440 * AVCodecContext. The resulting destination codec context will be
3441 * unopened, i.e. you are required to call avcodec_open2() before you
3442 * can use this AVCodecContext to decode/encode video/audio data.
3444 * @param dest target codec context, should be initialized with
3445 * avcodec_alloc_context3(NULL), but otherwise uninitialized
3446 * @param src source codec context
3447 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3449 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3451 #if FF_API_AVFRAME_LAVC
3453 * @deprecated use av_frame_alloc()
3455 attribute_deprecated
3456 AVFrame *avcodec_alloc_frame(void);
3459 * Set the fields of the given AVFrame to default values.
3461 * @param frame The AVFrame of which the fields should be set to default values.
3463 * @deprecated use av_frame_unref()
3465 attribute_deprecated
3466 void avcodec_get_frame_defaults(AVFrame *frame);
3469 * Free the frame and any dynamically allocated objects in it,
3470 * e.g. extended_data.
3472 * @param frame frame to be freed. The pointer will be set to NULL.
3474 * @warning this function does NOT free the data buffers themselves
3475 * (it does not know how, since they might have been allocated with
3476 * a custom get_buffer()).
3478 * @deprecated use av_frame_free()
3480 attribute_deprecated
3481 void avcodec_free_frame(AVFrame **frame);
3485 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3486 * function the context has to be allocated with avcodec_alloc_context3().
3488 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3489 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3490 * retrieving a codec.
3492 * @warning This function is not thread safe!
3495 * avcodec_register_all();
3496 * av_dict_set(&opts, "b", "2.5M", 0);
3497 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3501 * context = avcodec_alloc_context3(codec);
3503 * if (avcodec_open2(context, codec, opts) < 0)
3507 * @param avctx The context to initialize.
3508 * @param codec The codec to open this context for. If a non-NULL codec has been
3509 * previously passed to avcodec_alloc_context3() or
3510 * avcodec_get_context_defaults3() for this context, then this
3511 * parameter MUST be either NULL or equal to the previously passed
3513 * @param options A dictionary filled with AVCodecContext and codec-private options.
3514 * On return this object will be filled with options that were not found.
3516 * @return zero on success, a negative value on error
3517 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3518 * av_dict_set(), av_opt_find().
3520 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3523 * Close a given AVCodecContext and free all the data associated with it
3524 * (but not the AVCodecContext itself).
3526 * Calling this function on an AVCodecContext that hasn't been opened will free
3527 * the codec-specific data allocated in avcodec_alloc_context3() /
3528 * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
3531 int avcodec_close(AVCodecContext *avctx);
3534 * Free all allocated data in the given subtitle struct.
3536 * @param sub AVSubtitle to free.
3538 void avsubtitle_free(AVSubtitle *sub);
3545 * @addtogroup lavc_packet
3549 #if FF_API_DESTRUCT_PACKET
3551 * Default packet destructor.
3552 * @deprecated use the AVBuffer API instead
3554 attribute_deprecated
3555 void av_destruct_packet(AVPacket *pkt);
3559 * Initialize optional fields of a packet with default values.
3561 * Note, this does not touch the data and size members, which have to be
3562 * initialized separately.
3566 void av_init_packet(AVPacket *pkt);
3569 * Allocate the payload of a packet and initialize its fields with
3573 * @param size wanted payload size
3574 * @return 0 if OK, AVERROR_xxx otherwise
3576 int av_new_packet(AVPacket *pkt, int size);
3579 * Reduce packet size, correctly zeroing padding
3582 * @param size new size
3584 void av_shrink_packet(AVPacket *pkt, int size);
3587 * Increase packet size, correctly zeroing padding
3590 * @param grow_by number of bytes by which to increase the size of the packet
3592 int av_grow_packet(AVPacket *pkt, int grow_by);
3595 * Initialize a reference-counted packet from av_malloc()ed data.
3597 * @param pkt packet to be initialized. This function will set the data, size,
3598 * buf and destruct fields, all others are left untouched.
3599 * @param data Data allocated by av_malloc() to be used as packet data. If this
3600 * function returns successfully, the data is owned by the underlying AVBuffer.
3601 * The caller may not access the data through other means.
3602 * @param size size of data in bytes, without the padding. I.e. the full buffer
3603 * size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
3605 * @return 0 on success, a negative AVERROR on error
3607 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
3610 * @warning This is a hack - the packet memory allocation stuff is broken. The
3611 * packet is allocated if it was not really allocated.
3613 int av_dup_packet(AVPacket *pkt);
3616 * Copy packet, including contents
3618 * @return 0 on success, negative AVERROR on fail
3620 int av_copy_packet(AVPacket *dst, const AVPacket *src);
3623 * Copy packet side data
3625 * @return 0 on success, negative AVERROR on fail
3627 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
3632 * @param pkt packet to free
3634 void av_free_packet(AVPacket *pkt);
3637 * Allocate new information of a packet.
3640 * @param type side information type
3641 * @param size side information size
3642 * @return pointer to fresh allocated data or NULL otherwise
3644 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3648 * Shrink the already allocated side data buffer
3651 * @param type side information type
3652 * @param size new side information size
3653 * @return 0 on success, < 0 on failure
3655 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3659 * Get side information from packet.
3662 * @param type desired side information type
3663 * @param size pointer for side information size to store (optional)
3664 * @return pointer to data if present or NULL otherwise
3666 uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3669 int av_packet_merge_side_data(AVPacket *pkt);
3671 int av_packet_split_side_data(AVPacket *pkt);
3674 * Pack a dictionary for use in side_data.
3676 * @param dict The dictionary to pack.
3677 * @param size pointer to store the size of the returned data
3678 * @return pointer to data if successful, NULL otherwise
3680 uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size);
3682 * Unpack a dictionary from side_data.
3684 * @param data data from side_data
3685 * @param size size of the data
3686 * @param dict the metadata storage dictionary
3687 * @return 0 on success, < 0 on failure
3689 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
3693 * Convenience function to free all the side data stored.
3694 * All the other fields stay untouched.
3698 void av_packet_free_side_data(AVPacket *pkt);
3701 * Setup a new reference to the data described by a given packet
3703 * If src is reference-counted, setup dst as a new reference to the
3704 * buffer in src. Otherwise allocate a new buffer in dst and copy the
3705 * data from src into it.
3707 * All the other fields are copied from src.
3709 * @see av_packet_unref
3711 * @param dst Destination packet
3712 * @param src Source packet
3714 * @return 0 on success, a negative AVERROR on error.
3716 int av_packet_ref(AVPacket *dst, const AVPacket *src);
3721 * Unreference the buffer referenced by the packet and reset the
3722 * remaining packet fields to their default values.
3724 * @param pkt The packet to be unreferenced.
3726 void av_packet_unref(AVPacket *pkt);
3729 * Move every field in src to dst and reset src.
3731 * @see av_packet_unref
3733 * @param src Source packet, will be reset
3734 * @param dst Destination packet
3736 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
3739 * Copy only "properties" fields from src to dst.
3741 * Properties for the purpose of this function are all the fields
3742 * beside those related to the packet data (buf, data, size)
3744 * @param dst Destination packet
3745 * @param src Source packet
3747 * @return 0 on success AVERROR on failure.
3750 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
3757 * @addtogroup lavc_decoding
3762 * Find a registered decoder with a matching codec ID.
3764 * @param id AVCodecID of the requested decoder
3765 * @return A decoder if one was found, NULL otherwise.
3767 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3770 * Find a registered decoder with the specified name.
3772 * @param name name of the requested decoder
3773 * @return A decoder if one was found, NULL otherwise.
3775 AVCodec *avcodec_find_decoder_by_name(const char *name);
3777 #if FF_API_GET_BUFFER
3778 attribute_deprecated int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
3779 attribute_deprecated void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
3780 attribute_deprecated int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
3784 * The default callback for AVCodecContext.get_buffer2(). It is made public so
3785 * it can be called by custom get_buffer2() implementations for decoders without
3786 * CODEC_CAP_DR1 set.
3788 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
3792 * Return the amount of padding in pixels which the get_buffer callback must
3793 * provide around the edge of the image for codecs which do not have the
3794 * CODEC_FLAG_EMU_EDGE flag.
3796 * @return Required padding in pixels.
3798 * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
3801 attribute_deprecated
3802 unsigned avcodec_get_edge_width(void);
3806 * Modify width and height values so that they will result in a memory
3807 * buffer that is acceptable for the codec if you do not use any horizontal
3810 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3812 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3815 * Modify width and height values so that they will result in a memory
3816 * buffer that is acceptable for the codec if you also ensure that all
3817 * line sizes are a multiple of the respective linesize_align[i].
3819 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3821 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3822 int linesize_align[AV_NUM_DATA_POINTERS]);
3825 * Converts AVChromaLocation to swscale x/y chroma position.
3827 * The positions represent the chroma (0,0) position in a coordinates system
3828 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3830 * @param xpos horizontal chroma sample position
3831 * @param ypos vertical chroma sample position
3833 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
3836 * Converts swscale x/y chroma position to AVChromaLocation.
3838 * The positions represent the chroma (0,0) position in a coordinates system
3839 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3841 * @param xpos horizontal chroma sample position
3842 * @param ypos vertical chroma sample position
3844 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
3846 #if FF_API_OLD_DECODE_AUDIO
3848 * Wrapper function which calls avcodec_decode_audio4.
3850 * @deprecated Use avcodec_decode_audio4 instead.
3852 * Decode the audio frame of size avpkt->size from avpkt->data into samples.
3853 * Some decoders may support multiple frames in a single AVPacket, such
3854 * decoders would then just decode the first frame. In this case,
3855 * avcodec_decode_audio3 has to be called again with an AVPacket that contains
3856 * the remaining data in order to decode the second frame etc.
3858 * could be outputted, frame_size_ptr is zero. Otherwise, it is the
3859 * decompressed frame size in bytes.
3861 * @warning You must set frame_size_ptr to the allocated size of the
3862 * output buffer before calling avcodec_decode_audio3().
3864 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3865 * the actual read bytes because some optimized bitstream readers read 32 or 64
3866 * bits at once and could read over the end.
3868 * @warning The end of the input buffer avpkt->data should be set to 0 to ensure that
3869 * no overreading happens for damaged MPEG streams.
3871 * @warning You must not provide a custom get_buffer() when using
3872 * avcodec_decode_audio3(). Doing so will override it with
3873 * avcodec_default_get_buffer. Use avcodec_decode_audio4() instead,
3874 * which does allow the application to provide a custom get_buffer().
3876 * @note You might have to align the input buffer avpkt->data and output buffer
3877 * samples. The alignment requirements depend on the CPU: On some CPUs it isn't
3878 * necessary at all, on others it won't work at all if not aligned and on others
3879 * it will work but it will have an impact on performance.
3881 * In practice, avpkt->data should have 4 byte alignment at minimum and
3882 * samples should be 16 byte aligned unless the CPU doesn't need it
3883 * (AltiVec and SSE do).
3885 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3886 * between input and output, these need to be fed with avpkt->data=NULL,
3887 * avpkt->size=0 at the end to return the remaining frames.
3889 * @param avctx the codec context
3890 * @param[out] samples the output buffer, sample type in avctx->sample_fmt
3891 * If the sample format is planar, each channel plane will
3892 * be the same size, with no padding between channels.
3893 * @param[in,out] frame_size_ptr the output buffer size in bytes
3894 * @param[in] avpkt The input AVPacket containing the input buffer.
3895 * You can create such packet with av_init_packet() and by then setting
3896 * data and size, some decoders might in addition need other fields.
3897 * All decoders are designed to use the least fields possible though.
3898 * @return On error a negative value is returned, otherwise the number of bytes
3899 * used or zero if no frame data was decompressed (used) from the input AVPacket.
3901 attribute_deprecated int avcodec_decode_audio3(AVCodecContext *avctx, int16_t *samples,
3902 int *frame_size_ptr,
3907 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3909 * Some decoders may support multiple frames in a single AVPacket. Such
3910 * decoders would then just decode the first frame and the return value would be
3911 * less than the packet size. In this case, avcodec_decode_audio4 has to be
3912 * called again with an AVPacket containing the remaining data in order to
3913 * decode the second frame, etc... Even if no frames are returned, the packet
3914 * needs to be fed to the decoder with remaining data until it is completely
3915 * consumed or an error occurs.
3917 * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
3918 * and output. This means that for some packets they will not immediately
3919 * produce decoded output and need to be flushed at the end of decoding to get
3920 * all the decoded data. Flushing is done by calling this function with packets
3921 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3922 * returning samples. It is safe to flush even those decoders that are not
3923 * marked with CODEC_CAP_DELAY, then no samples will be returned.
3925 * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
3926 * larger than the actual read bytes because some optimized bitstream
3927 * readers read 32 or 64 bits at once and could read over the end.
3929 * @param avctx the codec context
3930 * @param[out] frame The AVFrame in which to store decoded audio samples.
3931 * The decoder will allocate a buffer for the decoded frame by
3932 * calling the AVCodecContext.get_buffer2() callback.
3933 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3934 * reference counted and the returned reference belongs to the
3935 * caller. The caller must release the frame using av_frame_unref()
3936 * when the frame is no longer needed. The caller may safely write
3937 * to the frame if av_frame_is_writable() returns 1.
3938 * When AVCodecContext.refcounted_frames is set to 0, the returned
3939 * reference belongs to the decoder and is valid only until the
3940 * next call to this function or until closing or flushing the
3941 * decoder. The caller may not write to it.
3942 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3943 * non-zero. Note that this field being set to zero
3944 * does not mean that an error has occurred. For
3945 * decoders with CODEC_CAP_DELAY set, no given decode
3946 * call is guaranteed to produce a frame.
3947 * @param[in] avpkt The input AVPacket containing the input buffer.
3948 * At least avpkt->data and avpkt->size should be set. Some
3949 * decoders might also require additional fields to be set.
3950 * @return A negative error code is returned if an error occurred during
3951 * decoding, otherwise the number of bytes consumed from the input
3952 * AVPacket is returned.
3954 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3955 int *got_frame_ptr, const AVPacket *avpkt);
3958 * Decode the video frame of size avpkt->size from avpkt->data into picture.
3959 * Some decoders may support multiple frames in a single AVPacket, such
3960 * decoders would then just decode the first frame.
3962 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3963 * the actual read bytes because some optimized bitstream readers read 32 or 64
3964 * bits at once and could read over the end.
3966 * @warning The end of the input buffer buf should be set to 0 to ensure that
3967 * no overreading happens for damaged MPEG streams.
3969 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3970 * between input and output, these need to be fed with avpkt->data=NULL,
3971 * avpkt->size=0 at the end to return the remaining frames.
3973 * @param avctx the codec context
3974 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3975 * Use av_frame_alloc() to get an AVFrame. The codec will
3976 * allocate memory for the actual bitmap by calling the
3977 * AVCodecContext.get_buffer2() callback.
3978 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3979 * reference counted and the returned reference belongs to the
3980 * caller. The caller must release the frame using av_frame_unref()
3981 * when the frame is no longer needed. The caller may safely write
3982 * to the frame if av_frame_is_writable() returns 1.
3983 * When AVCodecContext.refcounted_frames is set to 0, the returned
3984 * reference belongs to the decoder and is valid only until the
3985 * next call to this function or until closing or flushing the
3986 * decoder. The caller may not write to it.
3988 * @param[in] avpkt The input AVPacket containing the input buffer.
3989 * You can create such packet with av_init_packet() and by then setting
3990 * data and size, some decoders might in addition need other fields like
3991 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3993 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3994 * @return On error a negative value is returned, otherwise the number of bytes
3995 * used or zero if no frame could be decompressed.
3997 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3998 int *got_picture_ptr,
3999 const AVPacket *avpkt);
4002 * Decode a subtitle message.
4003 * Return a negative value on error, otherwise return the number of bytes used.
4004 * If no subtitle could be decompressed, got_sub_ptr is zero.
4005 * Otherwise, the subtitle is stored in *sub.
4006 * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4007 * simplicity, because the performance difference is expect to be negligible
4008 * and reusing a get_buffer written for video codecs would probably perform badly
4009 * due to a potentially very different allocation pattern.
4011 * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
4012 * and output. This means that for some packets they will not immediately
4013 * produce decoded output and need to be flushed at the end of decoding to get
4014 * all the decoded data. Flushing is done by calling this function with packets
4015 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4016 * returning subtitles. It is safe to flush even those decoders that are not
4017 * marked with CODEC_CAP_DELAY, then no subtitles will be returned.
4019 * @param avctx the codec context
4020 * @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
4021 freed with avsubtitle_free if *got_sub_ptr is set.
4022 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4023 * @param[in] avpkt The input AVPacket containing the input buffer.
4025 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
4030 * @defgroup lavc_parsing Frame parsing
4034 enum AVPictureStructure {
4035 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
4036 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4037 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4038 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4041 typedef struct AVCodecParserContext {
4043 struct AVCodecParser *parser;
4044 int64_t frame_offset; /* offset of the current frame */
4045 int64_t cur_offset; /* current offset
4046 (incremented by each av_parser_parse()) */
4047 int64_t next_frame_offset; /* offset of the next frame */
4049 int pict_type; /* XXX: Put it back in AVCodecContext. */
4051 * This field is used for proper frame duration computation in lavf.
4052 * It signals, how much longer the frame duration of the current frame
4053 * is compared to normal frame duration.
4055 * frame_duration = (1 + repeat_pict) * time_base
4057 * It is used by codecs like H.264 to display telecined material.
4059 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4060 int64_t pts; /* pts of the current frame */
4061 int64_t dts; /* dts of the current frame */
4066 int fetch_timestamp;
4068 #define AV_PARSER_PTS_NB 4
4069 int cur_frame_start_index;
4070 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
4071 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
4072 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
4075 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4076 #define PARSER_FLAG_ONCE 0x0002
4077 /// Set if the parser has a valid file offset
4078 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4079 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4081 int64_t offset; ///< byte offset from starting packet start
4082 int64_t cur_frame_end[AV_PARSER_PTS_NB];
4085 * Set by parser to 1 for key frames and 0 for non-key frames.
4086 * It is initialized to -1, so if the parser doesn't set this flag,
4087 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4093 * Time difference in stream time base units from the pts of this
4094 * packet to the point at which the output from the decoder has converged
4095 * independent from the availability of previous frames. That is, the
4096 * frames are virtually identical no matter if decoding started from
4097 * the very first frame or from this keyframe.
4098 * Is AV_NOPTS_VALUE if unknown.
4099 * This field is not the display duration of the current frame.
4100 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
4103 * The purpose of this field is to allow seeking in streams that have no
4104 * keyframes in the conventional sense. It corresponds to the
4105 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
4106 * essential for some types of subtitle streams to ensure that all
4107 * subtitles are correctly displayed after seeking.
4109 int64_t convergence_duration;
4111 // Timestamp generation support:
4113 * Synchronization point for start of timestamp generation.
4115 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4118 * For example, this corresponds to presence of H.264 buffering period
4124 * Offset of the current timestamp against last timestamp sync point in
4125 * units of AVCodecContext.time_base.
4127 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4128 * contain a valid timestamp offset.
4130 * Note that the timestamp of sync point has usually a nonzero
4131 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
4132 * the next frame after timestamp sync point will be usually 1.
4134 * For example, this corresponds to H.264 cpb_removal_delay.
4136 int dts_ref_dts_delta;
4139 * Presentation delay of current frame in units of AVCodecContext.time_base.
4141 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4142 * contain valid non-negative timestamp delta (presentation time of a frame
4143 * must not lie in the past).
4145 * This delay represents the difference between decoding and presentation
4146 * time of the frame.
4148 * For example, this corresponds to H.264 dpb_output_delay.
4153 * Position of the packet in file.
4155 * Analogous to cur_frame_pts/dts
4157 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
4160 * Byte position of currently parsed frame in stream.
4165 * Previous frame byte position.
4170 * Duration of the current frame.
4171 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4172 * For all other types, this is in units of AVCodecContext.time_base.
4176 enum AVFieldOrder field_order;
4179 * Indicate whether a picture is coded as a frame, top field or bottom field.
4181 * For example, H.264 field_pic_flag equal to 0 corresponds to
4182 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
4183 * equal to 1 and bottom_field_flag equal to 0 corresponds to
4184 * AV_PICTURE_STRUCTURE_TOP_FIELD.
4186 enum AVPictureStructure picture_structure;
4189 * Picture number incremented in presentation or output order.
4190 * This field may be reinitialized at the first picture of a new sequence.
4192 * For example, this corresponds to H.264 PicOrderCnt.
4194 int output_picture_number;
4195 } AVCodecParserContext;
4197 typedef struct AVCodecParser {
4198 int codec_ids[5]; /* several codec IDs are permitted */
4200 int (*parser_init)(AVCodecParserContext *s);
4201 int (*parser_parse)(AVCodecParserContext *s,
4202 AVCodecContext *avctx,
4203 const uint8_t **poutbuf, int *poutbuf_size,
4204 const uint8_t *buf, int buf_size);
4205 void (*parser_close)(AVCodecParserContext *s);
4206 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
4207 struct AVCodecParser *next;
4210 AVCodecParser *av_parser_next(AVCodecParser *c);
4212 void av_register_codec_parser(AVCodecParser *parser);
4213 AVCodecParserContext *av_parser_init(int codec_id);
4218 * @param s parser context.
4219 * @param avctx codec context.
4220 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
4221 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
4222 * @param buf input buffer.
4223 * @param buf_size input length, to signal EOF, this should be 0 (so that the last frame can be output).
4224 * @param pts input presentation timestamp.
4225 * @param dts input decoding timestamp.
4226 * @param pos input byte position in stream.
4227 * @return the number of bytes of the input bitstream used.
4232 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
4239 * decode_frame(data, size);
4243 int av_parser_parse2(AVCodecParserContext *s,
4244 AVCodecContext *avctx,
4245 uint8_t **poutbuf, int *poutbuf_size,
4246 const uint8_t *buf, int buf_size,
4247 int64_t pts, int64_t dts,
4251 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
4252 * @deprecated use AVBitStreamFilter
4254 int av_parser_change(AVCodecParserContext *s,
4255 AVCodecContext *avctx,
4256 uint8_t **poutbuf, int *poutbuf_size,
4257 const uint8_t *buf, int buf_size, int keyframe);
4258 void av_parser_close(AVCodecParserContext *s);
4266 * @addtogroup lavc_encoding
4271 * Find a registered encoder with a matching codec ID.
4273 * @param id AVCodecID of the requested encoder
4274 * @return An encoder if one was found, NULL otherwise.
4276 AVCodec *avcodec_find_encoder(enum AVCodecID id);
4279 * Find a registered encoder with the specified name.
4281 * @param name name of the requested encoder
4282 * @return An encoder if one was found, NULL otherwise.
4284 AVCodec *avcodec_find_encoder_by_name(const char *name);
4286 #if FF_API_OLD_ENCODE_AUDIO
4288 * Encode an audio frame from samples into buf.
4290 * @deprecated Use avcodec_encode_audio2 instead.
4292 * @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
4293 * However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
4294 * will know how much space is needed because it depends on the value passed
4295 * in buf_size as described below. In that case a lower value can be used.
4297 * @param avctx the codec context
4298 * @param[out] buf the output buffer
4299 * @param[in] buf_size the output buffer size
4300 * @param[in] samples the input buffer containing the samples
4301 * The number of samples read from this buffer is frame_size*channels,
4302 * both of which are defined in avctx.
4303 * For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
4304 * samples read from samples is equal to:
4305 * buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
4306 * This also implies that av_get_bits_per_sample() must not return 0 for these
4308 * @return On error a negative value is returned, on success zero or the number
4309 * of bytes used to encode the data read from the input buffer.
4311 int attribute_deprecated avcodec_encode_audio(AVCodecContext *avctx,
4312 uint8_t *buf, int buf_size,
4313 const short *samples);
4317 * Encode a frame of audio.
4319 * Takes input samples from frame and writes the next output packet, if
4320 * available, to avpkt. The output packet does not necessarily contain data for
4321 * the most recent frame, as encoders can delay, split, and combine input frames
4322 * internally as needed.
4324 * @param avctx codec context
4325 * @param avpkt output AVPacket.
4326 * The user can supply an output buffer by setting
4327 * avpkt->data and avpkt->size prior to calling the
4328 * function, but if the size of the user-provided data is not
4329 * large enough, encoding will fail. If avpkt->data and
4330 * avpkt->size are set, avpkt->destruct must also be set. All
4331 * other AVPacket fields will be reset by the encoder using
4332 * av_init_packet(). If avpkt->data is NULL, the encoder will
4333 * allocate it. The encoder will set avpkt->size to the size
4334 * of the output packet.
4336 * If this function fails or produces no output, avpkt will be
4337 * freed using av_free_packet() (i.e. avpkt->destruct will be
4338 * called to free the user supplied buffer).
4339 * @param[in] frame AVFrame containing the raw audio data to be encoded.
4340 * May be NULL when flushing an encoder that has the
4341 * CODEC_CAP_DELAY capability set.
4342 * If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4343 * can have any number of samples.
4344 * If it is not set, frame->nb_samples must be equal to
4345 * avctx->frame_size for all frames except the last.
4346 * The final frame may be smaller than avctx->frame_size.
4347 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4348 * output packet is non-empty, and to 0 if it is
4349 * empty. If the function returns an error, the
4350 * packet can be assumed to be invalid, and the
4351 * value of got_packet_ptr is undefined and should
4353 * @return 0 on success, negative error code on failure
4355 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
4356 const AVFrame *frame, int *got_packet_ptr);
4358 #if FF_API_OLD_ENCODE_VIDEO
4360 * @deprecated use avcodec_encode_video2() instead.
4362 * Encode a video frame from pict into buf.
4363 * The input picture should be
4364 * stored using a specific format, namely avctx.pix_fmt.
4366 * @param avctx the codec context
4367 * @param[out] buf the output buffer for the bitstream of encoded frame
4368 * @param[in] buf_size the size of the output buffer in bytes
4369 * @param[in] pict the input picture to encode
4370 * @return On error a negative value is returned, on success zero or the number
4371 * of bytes used from the output buffer.
4373 attribute_deprecated
4374 int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4375 const AVFrame *pict);
4379 * Encode a frame of video.
4381 * Takes input raw video data from frame and writes the next output packet, if
4382 * available, to avpkt. The output packet does not necessarily contain data for
4383 * the most recent frame, as encoders can delay and reorder input frames
4384 * internally as needed.
4386 * @param avctx codec context
4387 * @param avpkt output AVPacket.
4388 * The user can supply an output buffer by setting
4389 * avpkt->data and avpkt->size prior to calling the
4390 * function, but if the size of the user-provided data is not
4391 * large enough, encoding will fail. All other AVPacket fields
4392 * will be reset by the encoder using av_init_packet(). If
4393 * avpkt->data is NULL, the encoder will allocate it.
4394 * The encoder will set avpkt->size to the size of the
4395 * output packet. The returned data (if any) belongs to the
4396 * caller, he is responsible for freeing it.
4398 * If this function fails or produces no output, avpkt will be
4399 * freed using av_free_packet() (i.e. avpkt->destruct will be
4400 * called to free the user supplied buffer).
4401 * @param[in] frame AVFrame containing the raw video data to be encoded.
4402 * May be NULL when flushing an encoder that has the
4403 * CODEC_CAP_DELAY capability set.
4404 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4405 * output packet is non-empty, and to 0 if it is
4406 * empty. If the function returns an error, the
4407 * packet can be assumed to be invalid, and the
4408 * value of got_packet_ptr is undefined and should
4410 * @return 0 on success, negative error code on failure
4412 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
4413 const AVFrame *frame, int *got_packet_ptr);
4415 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4416 const AVSubtitle *sub);
4423 #if FF_API_AVCODEC_RESAMPLE
4425 * @defgroup lavc_resample Audio resampling
4427 * @deprecated use libswresample instead
4431 struct ReSampleContext;
4432 struct AVResampleContext;
4434 typedef struct ReSampleContext ReSampleContext;
4437 * Initialize audio resampling context.
4439 * @param output_channels number of output channels
4440 * @param input_channels number of input channels
4441 * @param output_rate output sample rate
4442 * @param input_rate input sample rate
4443 * @param sample_fmt_out requested output sample format
4444 * @param sample_fmt_in input sample format
4445 * @param filter_length length of each FIR filter in the filterbank relative to the cutoff frequency
4446 * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4447 * @param linear if 1 then the used FIR filter will be linearly interpolated
4448 between the 2 closest, if 0 the closest will be used
4449 * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4450 * @return allocated ReSampleContext, NULL if error occurred
4452 attribute_deprecated
4453 ReSampleContext *av_audio_resample_init(int output_channels, int input_channels,
4454 int output_rate, int input_rate,
4455 enum AVSampleFormat sample_fmt_out,
4456 enum AVSampleFormat sample_fmt_in,
4457 int filter_length, int log2_phase_count,
4458 int linear, double cutoff);
4460 attribute_deprecated
4461 int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
4464 * Free resample context.
4466 * @param s a non-NULL pointer to a resample context previously
4467 * created with av_audio_resample_init()
4469 attribute_deprecated
4470 void audio_resample_close(ReSampleContext *s);
4474 * Initialize an audio resampler.
4475 * Note, if either rate is not an integer then simply scale both rates up so they are.
4476 * @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
4477 * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4478 * @param linear If 1 then the used FIR filter will be linearly interpolated
4479 between the 2 closest, if 0 the closest will be used
4480 * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4482 attribute_deprecated
4483 struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff);
4486 * Resample an array of samples using a previously configured context.
4487 * @param src an array of unconsumed samples
4488 * @param consumed the number of samples of src which have been consumed are returned here
4489 * @param src_size the number of unconsumed samples available
4490 * @param dst_size the amount of space in samples available in dst
4491 * @param update_ctx If this is 0 then the context will not be modified, that way several channels can be resampled with the same context.
4492 * @return the number of samples written in dst or -1 if an error occurred
4494 attribute_deprecated
4495 int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx);
4499 * Compensate samplerate/timestamp drift. The compensation is done by changing
4500 * the resampler parameters, so no audible clicks or similar distortions occur
4501 * @param compensation_distance distance in output samples over which the compensation should be performed
4502 * @param sample_delta number of output samples which should be output less
4504 * example: av_resample_compensate(c, 10, 500)
4505 * here instead of 510 samples only 500 samples would be output
4507 * note, due to rounding the actual compensation might be slightly different,
4508 * especially if the compensation_distance is large and the in_rate used during init is small
4510 attribute_deprecated
4511 void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance);
4512 attribute_deprecated
4513 void av_resample_close(struct AVResampleContext *c);
4521 * @addtogroup lavc_picture
4526 * Allocate memory for the pixels of a picture and setup the AVPicture
4529 * Call avpicture_free() to free it.
4531 * @param picture the picture structure to be filled in
4532 * @param pix_fmt the pixel format of the picture
4533 * @param width the width of the picture
4534 * @param height the height of the picture
4535 * @return zero if successful, a negative error code otherwise
4537 * @see av_image_alloc(), avpicture_fill()
4539 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
4542 * Free a picture previously allocated by avpicture_alloc().
4543 * The data buffer used by the AVPicture is freed, but the AVPicture structure
4546 * @param picture the AVPicture to be freed
4548 void avpicture_free(AVPicture *picture);
4551 * Setup the picture fields based on the specified image parameters
4552 * and the provided image data buffer.
4554 * The picture fields are filled in by using the image data buffer
4555 * pointed to by ptr.
4557 * If ptr is NULL, the function will fill only the picture linesize
4558 * array and return the required size for the image buffer.
4560 * To allocate an image buffer and fill the picture data in one call,
4561 * use avpicture_alloc().
4563 * @param picture the picture to be filled in
4564 * @param ptr buffer where the image data is stored, or NULL
4565 * @param pix_fmt the pixel format of the image
4566 * @param width the width of the image in pixels
4567 * @param height the height of the image in pixels
4568 * @return the size in bytes required for src, a negative error code
4569 * in case of failure
4571 * @see av_image_fill_arrays()
4573 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
4574 enum AVPixelFormat pix_fmt, int width, int height);
4577 * Copy pixel data from an AVPicture into a buffer.
4579 * avpicture_get_size() can be used to compute the required size for
4580 * the buffer to fill.
4582 * @param src source picture with filled data
4583 * @param pix_fmt picture pixel format
4584 * @param width picture width
4585 * @param height picture height
4586 * @param dest destination buffer
4587 * @param dest_size destination buffer size in bytes
4588 * @return the number of bytes written to dest, or a negative value
4589 * (error code) on error, for example if the destination buffer is not
4592 * @see av_image_copy_to_buffer()
4594 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
4595 int width, int height,
4596 unsigned char *dest, int dest_size);
4599 * Calculate the size in bytes that a picture of the given width and height
4600 * would occupy if stored in the given picture format.
4602 * @param pix_fmt picture pixel format
4603 * @param width picture width
4604 * @param height picture height
4605 * @return the computed picture buffer size or a negative error code
4608 * @see av_image_get_buffer_size().
4610 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
4612 #if FF_API_DEINTERLACE
4614 * deinterlace - if not supported return -1
4616 * @deprecated - use yadif (in libavfilter) instead
4618 attribute_deprecated
4619 int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
4620 enum AVPixelFormat pix_fmt, int width, int height);
4623 * Copy image src to dst. Wraps av_image_copy().
4625 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4626 enum AVPixelFormat pix_fmt, int width, int height);
4629 * Crop image top and left side.
4631 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4632 enum AVPixelFormat pix_fmt, int top_band, int left_band);
4637 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
4638 int padtop, int padbottom, int padleft, int padright, int *color);
4645 * @defgroup lavc_misc Utility functions
4648 * Miscellaneous utility functions related to both encoding and decoding
4654 * @defgroup lavc_misc_pixfmt Pixel formats
4656 * Functions for working with pixel formats.
4661 * Utility function to access log2_chroma_w log2_chroma_h from
4662 * the pixel format AVPixFmtDescriptor.
4664 * This function asserts that pix_fmt is valid. See av_pix_fmt_get_chroma_sub_sample
4665 * for one that returns a failure code and continues in case of invalid
4668 * @param[in] pix_fmt the pixel format
4669 * @param[out] h_shift store log2_chroma_w
4670 * @param[out] v_shift store log2_chroma_h
4672 * @see av_pix_fmt_get_chroma_sub_sample
4675 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
4678 * Return a value representing the fourCC code associated to the
4679 * pixel format pix_fmt, or 0 if no associated fourCC code can be
4682 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
4684 #define FF_LOSS_RESOLUTION 0x0001 /**< loss due to resolution change */
4685 #define FF_LOSS_DEPTH 0x0002 /**< loss due to color depth change */
4686 #define FF_LOSS_COLORSPACE 0x0004 /**< loss due to color space conversion */
4687 #define FF_LOSS_ALPHA 0x0008 /**< loss of alpha bits */
4688 #define FF_LOSS_COLORQUANT 0x0010 /**< loss due to color quantization */
4689 #define FF_LOSS_CHROMA 0x0020 /**< loss of chroma (e.g. RGB to gray conversion) */
4692 * Compute what kind of losses will occur when converting from one specific
4693 * pixel format to another.
4694 * When converting from one pixel format to another, information loss may occur.
4695 * For example, when converting from RGB24 to GRAY, the color information will
4696 * be lost. Similarly, other losses occur when converting from some formats to
4697 * other formats. These losses can involve loss of chroma, but also loss of
4698 * resolution, loss of color depth, loss due to the color space conversion, loss
4699 * of the alpha bits or loss due to color quantization.
4700 * avcodec_get_fix_fmt_loss() informs you about the various types of losses
4701 * which will occur when converting from one pixel format to another.
4703 * @param[in] dst_pix_fmt destination pixel format
4704 * @param[in] src_pix_fmt source pixel format
4705 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4706 * @return Combination of flags informing you what kind of losses will occur
4707 * (maximum loss for an invalid dst_pix_fmt).
4709 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
4713 * Find the best pixel format to convert to given a certain source pixel
4714 * format. When converting from one pixel format to another, information loss
4715 * may occur. For example, when converting from RGB24 to GRAY, the color
4716 * information will be lost. Similarly, other losses occur when converting from
4717 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
4718 * the given pixel formats should be used to suffer the least amount of loss.
4719 * The pixel formats from which it chooses one, are determined by the
4720 * pix_fmt_list parameter.
4723 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
4724 * @param[in] src_pix_fmt source pixel format
4725 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4726 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4727 * @return The best pixel format to convert to or -1 if none was found.
4729 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
4730 enum AVPixelFormat src_pix_fmt,
4731 int has_alpha, int *loss_ptr);
4734 * Find the best pixel format to convert to given a certain source pixel
4735 * format and a selection of two destination pixel formats. When converting from
4736 * one pixel format to another, information loss may occur. For example, when converting
4737 * from RGB24 to GRAY, the color information will be lost. Similarly, other losses occur when
4738 * converting from some formats to other formats. avcodec_find_best_pix_fmt_of_2() selects which of
4739 * the given pixel formats should be used to suffer the least amount of loss.
4741 * If one of the destination formats is AV_PIX_FMT_NONE the other pixel format (if valid) will be
4745 * src_pix_fmt = AV_PIX_FMT_YUV420P;
4746 * dst_pix_fmt1= AV_PIX_FMT_RGB24;
4747 * dst_pix_fmt2= AV_PIX_FMT_GRAY8;
4748 * dst_pix_fmt3= AV_PIX_FMT_RGB8;
4749 * loss= FF_LOSS_CHROMA; // don't care about chroma loss, so chroma loss will be ignored.
4750 * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt1, dst_pix_fmt2, src_pix_fmt, alpha, &loss);
4751 * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt, dst_pix_fmt3, src_pix_fmt, alpha, &loss);
4754 * @param[in] dst_pix_fmt1 One of the two destination pixel formats to choose from
4755 * @param[in] dst_pix_fmt2 The other of the two destination pixel formats to choose from
4756 * @param[in] src_pix_fmt Source pixel format
4757 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4758 * @param[in, out] loss_ptr Combination of loss flags. In: selects which of the losses to ignore, i.e.
4759 * NULL or value of zero means we care about all losses. Out: the loss
4760 * that occurs when converting from src to selected dst pixel format.
4761 * @return The best pixel format to convert to or -1 if none was found.
4763 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4764 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4766 attribute_deprecated
4767 #if AV_HAVE_INCOMPATIBLE_LIBAV_ABI
4768 enum AVPixelFormat avcodec_find_best_pix_fmt2(const enum AVPixelFormat *pix_fmt_list,
4769 enum AVPixelFormat src_pix_fmt,
4770 int has_alpha, int *loss_ptr);
4772 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4773 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4777 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
4783 #if FF_API_SET_DIMENSIONS
4785 * @deprecated this function is not supposed to be used from outside of lavc
4787 attribute_deprecated
4788 void avcodec_set_dimensions(AVCodecContext *s, int width, int height);
4792 * Put a string representing the codec tag codec_tag in buf.
4794 * @param buf buffer to place codec tag in
4795 * @param buf_size size in bytes of buf
4796 * @param codec_tag codec tag to assign
4797 * @return the length of the string that would have been generated if
4798 * enough space had been available, excluding the trailing null
4800 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
4802 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
4805 * Return a name for the specified profile, if available.
4807 * @param codec the codec that is searched for the given profile
4808 * @param profile the profile value for which a name is requested
4809 * @return A name for the profile if found, NULL otherwise.
4811 const char *av_get_profile_name(const AVCodec *codec, int profile);
4813 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
4814 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
4815 //FIXME func typedef
4818 * Fill AVFrame audio data and linesize pointers.
4820 * The buffer buf must be a preallocated buffer with a size big enough
4821 * to contain the specified samples amount. The filled AVFrame data
4822 * pointers will point to this buffer.
4824 * AVFrame extended_data channel pointers are allocated if necessary for
4827 * @param frame the AVFrame
4828 * frame->nb_samples must be set prior to calling the
4829 * function. This function fills in frame->data,
4830 * frame->extended_data, frame->linesize[0].
4831 * @param nb_channels channel count
4832 * @param sample_fmt sample format
4833 * @param buf buffer to use for frame data
4834 * @param buf_size size of buffer
4835 * @param align plane size sample alignment (0 = default)
4836 * @return >=0 on success, negative error code on failure
4837 * @todo return the size in bytes required to store the samples in
4838 * case of success, at the next libavutil bump
4840 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
4841 enum AVSampleFormat sample_fmt, const uint8_t *buf,
4842 int buf_size, int align);
4845 * Reset the internal decoder state / flush internal buffers. Should be called
4846 * e.g. when seeking or when switching to a different stream.
4848 * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
4849 * this invalidates the frames previously returned from the decoder. When
4850 * refcounted frames are used, the decoder just releases any references it might
4851 * keep internally, but the caller's reference remains valid.
4853 void avcodec_flush_buffers(AVCodecContext *avctx);
4856 * Return codec bits per sample.
4858 * @param[in] codec_id the codec
4859 * @return Number of bits per sample or zero if unknown for the given codec.
4861 int av_get_bits_per_sample(enum AVCodecID codec_id);
4864 * Return the PCM codec associated with a sample format.
4865 * @param be endianness, 0 for little, 1 for big,
4866 * -1 (or anything else) for native
4867 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
4869 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
4872 * Return codec bits per sample.
4873 * Only return non-zero if the bits per sample is exactly correct, not an
4876 * @param[in] codec_id the codec
4877 * @return Number of bits per sample or zero if unknown for the given codec.
4879 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
4882 * Return audio frame duration.
4884 * @param avctx codec context
4885 * @param frame_bytes size of the frame, or 0 if unknown
4886 * @return frame duration, in samples, if known. 0 if not able to
4889 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4892 typedef struct AVBitStreamFilterContext {
4894 struct AVBitStreamFilter *filter;
4895 AVCodecParserContext *parser;
4896 struct AVBitStreamFilterContext *next;
4897 } AVBitStreamFilterContext;
4900 typedef struct AVBitStreamFilter {
4903 int (*filter)(AVBitStreamFilterContext *bsfc,
4904 AVCodecContext *avctx, const char *args,
4905 uint8_t **poutbuf, int *poutbuf_size,
4906 const uint8_t *buf, int buf_size, int keyframe);
4907 void (*close)(AVBitStreamFilterContext *bsfc);
4908 struct AVBitStreamFilter *next;
4909 } AVBitStreamFilter;
4912 * Register a bitstream filter.
4914 * The filter will be accessible to the application code through
4915 * av_bitstream_filter_next() or can be directly initialized with
4916 * av_bitstream_filter_init().
4918 * @see avcodec_register_all()
4920 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4923 * Create and initialize a bitstream filter context given a bitstream
4926 * The returned context must be freed with av_bitstream_filter_close().
4928 * @param name the name of the bitstream filter
4929 * @return a bitstream filter context if a matching filter was found
4930 * and successfully initialized, NULL otherwise
4932 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4937 * This function filters the buffer buf with size buf_size, and places the
4938 * filtered buffer in the buffer pointed to by poutbuf.
4940 * The output buffer must be freed by the caller.
4942 * @param bsfc bitstream filter context created by av_bitstream_filter_init()
4943 * @param avctx AVCodecContext accessed by the filter, may be NULL.
4944 * If specified, this must point to the encoder context of the
4945 * output stream the packet is sent to.
4946 * @param args arguments which specify the filter configuration, may be NULL
4947 * @param poutbuf pointer which is updated to point to the filtered buffer
4948 * @param poutbuf_size pointer which is updated to the filtered buffer size in bytes
4949 * @param buf buffer containing the data to filter
4950 * @param buf_size size in bytes of buf
4951 * @param keyframe set to non-zero if the buffer to filter corresponds to a key-frame packet data
4952 * @return >= 0 in case of success, or a negative error code in case of failure
4954 * If the return value is positive, an output buffer is allocated and
4955 * is availble in *poutbuf, and is distinct from the input buffer.
4957 * If the return value is 0, the output buffer is not allocated and
4958 * should be considered identical to the input buffer, or in case
4959 * *poutbuf was set it points to the input buffer (not necessarily to
4960 * its starting address).
4962 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4963 AVCodecContext *avctx, const char *args,
4964 uint8_t **poutbuf, int *poutbuf_size,
4965 const uint8_t *buf, int buf_size, int keyframe);
4968 * Release bitstream filter context.
4970 * @param bsf the bitstream filter context created with
4971 * av_bitstream_filter_init(), can be NULL
4973 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4976 * If f is NULL, return the first registered bitstream filter,
4977 * if f is non-NULL, return the next registered bitstream filter
4978 * after f, or NULL if f is the last one.
4980 * This function can be used to iterate over all registered bitstream
4983 AVBitStreamFilter *av_bitstream_filter_next(AVBitStreamFilter *f);
4988 * Same behaviour av_fast_malloc but the buffer has additional
4989 * FF_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
4991 * In addition the whole buffer will initially and after resizes
4992 * be 0-initialized so that no uninitialized data will ever appear.
4994 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4997 * Same behaviour av_fast_padded_malloc except that buffer will always
4998 * be 0-initialized after call.
5000 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
5003 * Encode extradata length to a buffer. Used by xiph codecs.
5005 * @param s buffer to write to; must be at least (v/255+1) bytes long
5006 * @param v size of extradata in bytes
5007 * @return number of bytes written to the buffer.
5009 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
5011 #if FF_API_MISSING_SAMPLE
5013 * Log a generic warning message about a missing feature. This function is
5014 * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
5015 * only, and would normally not be used by applications.
5016 * @param[in] avc a pointer to an arbitrary struct of which the first field is
5017 * a pointer to an AVClass struct
5018 * @param[in] feature string containing the name of the missing feature
5019 * @param[in] want_sample indicates if samples are wanted which exhibit this feature.
5020 * If want_sample is non-zero, additional verbage will be added to the log
5021 * message which tells the user how to report samples to the development
5023 * @deprecated Use avpriv_report_missing_feature() instead.
5025 attribute_deprecated
5026 void av_log_missing_feature(void *avc, const char *feature, int want_sample);
5029 * Log a generic warning message asking for a sample. This function is
5030 * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
5031 * only, and would normally not be used by applications.
5032 * @param[in] avc a pointer to an arbitrary struct of which the first field is
5033 * a pointer to an AVClass struct
5034 * @param[in] msg string containing an optional message, or NULL if no message
5035 * @deprecated Use avpriv_request_sample() instead.
5037 attribute_deprecated
5038 void av_log_ask_for_sample(void *avc, const char *msg, ...) av_printf_format(2, 3);
5039 #endif /* FF_API_MISSING_SAMPLE */
5042 * Register the hardware accelerator hwaccel.
5044 void av_register_hwaccel(AVHWAccel *hwaccel);
5047 * If hwaccel is NULL, returns the first registered hardware accelerator,
5048 * if hwaccel is non-NULL, returns the next registered hardware accelerator
5049 * after hwaccel, or NULL if hwaccel is the last one.
5051 AVHWAccel *av_hwaccel_next(AVHWAccel *hwaccel);
5055 * Lock operation used by lockmgr
5058 AV_LOCK_CREATE, ///< Create a mutex
5059 AV_LOCK_OBTAIN, ///< Lock the mutex
5060 AV_LOCK_RELEASE, ///< Unlock the mutex
5061 AV_LOCK_DESTROY, ///< Free mutex resources
5065 * Register a user provided lock manager supporting the operations
5066 * specified by AVLockOp. mutex points to a (void *) where the
5067 * lockmgr should store/get a pointer to a user allocated mutex. It's
5068 * NULL upon AV_LOCK_CREATE and != NULL for all other ops.
5070 * @param cb User defined callback. Note: FFmpeg may invoke calls to this
5071 * callback during the call to av_lockmgr_register().
5072 * Thus, the application must be prepared to handle that.
5073 * If cb is set to NULL the lockmgr will be unregistered.
5074 * Also note that during unregistration the previously registered
5075 * lockmgr callback may also be invoked.
5077 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
5080 * Get the type of the given codec.
5082 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
5085 * Get the name of a codec.
5086 * @return a static string identifying the codec; never NULL
5088 const char *avcodec_get_name(enum AVCodecID id);
5091 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
5092 * with no corresponding avcodec_close()), 0 otherwise.
5094 int avcodec_is_open(AVCodecContext *s);
5097 * @return a non-zero number if codec is an encoder, zero otherwise
5099 int av_codec_is_encoder(const AVCodec *codec);
5102 * @return a non-zero number if codec is a decoder, zero otherwise
5104 int av_codec_is_decoder(const AVCodec *codec);
5107 * @return descriptor for given codec ID or NULL if no descriptor exists.
5109 const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
5112 * Iterate over all codec descriptors known to libavcodec.
5114 * @param prev previous descriptor. NULL to get the first descriptor.
5116 * @return next descriptor or NULL after the last descriptor
5118 const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
5121 * @return codec descriptor with the given name or NULL if no such descriptor
5124 const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
5130 #endif /* AVCODEC_AVCODEC_H */