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,
488 AV_CODEC_ID_FFWAVESYNTH = MKBETAG('F','F','W','S'),
489 AV_CODEC_ID_SONIC = MKBETAG('S','O','N','C'),
490 AV_CODEC_ID_SONIC_LS = MKBETAG('S','O','N','L'),
491 AV_CODEC_ID_PAF_AUDIO = MKBETAG('P','A','F','A'),
492 AV_CODEC_ID_OPUS = MKBETAG('O','P','U','S'),
493 AV_CODEC_ID_TAK = MKBETAG('t','B','a','K'),
494 AV_CODEC_ID_EVRC = MKBETAG('s','e','v','c'),
495 AV_CODEC_ID_SMV = MKBETAG('s','s','m','v'),
496 AV_CODEC_ID_DSD_LSBF = MKBETAG('D','S','D','L'),
497 AV_CODEC_ID_DSD_MSBF = MKBETAG('D','S','D','M'),
498 AV_CODEC_ID_DSD_LSBF_PLANAR = MKBETAG('D','S','D','1'),
499 AV_CODEC_ID_DSD_MSBF_PLANAR = MKBETAG('D','S','D','8'),
501 /* subtitle codecs */
502 AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
503 AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
504 AV_CODEC_ID_DVB_SUBTITLE,
505 AV_CODEC_ID_TEXT, ///< raw UTF-8 text
508 AV_CODEC_ID_MOV_TEXT,
509 AV_CODEC_ID_HDMV_PGS_SUBTITLE,
510 AV_CODEC_ID_DVB_TELETEXT,
512 AV_CODEC_ID_MICRODVD = MKBETAG('m','D','V','D'),
513 AV_CODEC_ID_EIA_608 = MKBETAG('c','6','0','8'),
514 AV_CODEC_ID_JACOSUB = MKBETAG('J','S','U','B'),
515 AV_CODEC_ID_SAMI = MKBETAG('S','A','M','I'),
516 AV_CODEC_ID_REALTEXT = MKBETAG('R','T','X','T'),
517 AV_CODEC_ID_SUBVIEWER1 = MKBETAG('S','b','V','1'),
518 AV_CODEC_ID_SUBVIEWER = MKBETAG('S','u','b','V'),
519 AV_CODEC_ID_SUBRIP = MKBETAG('S','R','i','p'),
520 AV_CODEC_ID_WEBVTT = MKBETAG('W','V','T','T'),
521 AV_CODEC_ID_MPL2 = MKBETAG('M','P','L','2'),
522 AV_CODEC_ID_VPLAYER = MKBETAG('V','P','l','r'),
523 AV_CODEC_ID_PJS = MKBETAG('P','h','J','S'),
524 AV_CODEC_ID_ASS = MKBETAG('A','S','S',' '), ///< ASS as defined in Matroska
526 /* other specific kind of codecs (generally used for attachments) */
527 AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
528 AV_CODEC_ID_TTF = 0x18000,
529 AV_CODEC_ID_BINTEXT = MKBETAG('B','T','X','T'),
530 AV_CODEC_ID_XBIN = MKBETAG('X','B','I','N'),
531 AV_CODEC_ID_IDF = MKBETAG( 0 ,'I','D','F'),
532 AV_CODEC_ID_OTF = MKBETAG( 0 ,'O','T','F'),
533 AV_CODEC_ID_SMPTE_KLV = MKBETAG('K','L','V','A'),
534 AV_CODEC_ID_DVD_NAV = MKBETAG('D','N','A','V'),
535 AV_CODEC_ID_TIMED_ID3 = MKBETAG('T','I','D','3'),
538 AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
540 AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
541 * stream (only used by libavformat) */
542 AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
543 * stream (only used by libavformat) */
544 AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
547 #include "old_codec_ids.h"
552 * This struct describes the properties of a single codec described by an
554 * @see avcodec_get_descriptor()
556 typedef struct AVCodecDescriptor {
558 enum AVMediaType type;
560 * Name of the codec described by this descriptor. It is non-empty and
561 * unique for each codec descriptor. It should contain alphanumeric
562 * characters and '_' only.
566 * A more descriptive name for this codec. May be NULL.
568 const char *long_name;
570 * Codec properties, a combination of AV_CODEC_PROP_* flags.
576 * Codec uses only intra compression.
579 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
581 * Codec supports lossy compression. Audio and video codecs only.
582 * @note a codec may support both lossy and lossless
585 #define AV_CODEC_PROP_LOSSY (1 << 1)
587 * Codec supports lossless compression. Audio and video codecs only.
589 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
591 * Subtitle codec is bitmap based
592 * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
594 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
596 * Subtitle codec is text based.
597 * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
599 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
602 * @ingroup lavc_decoding
603 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
604 * This is mainly needed because some optimized bitstream readers read
605 * 32 or 64 bit at once and could read over the end.<br>
606 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
607 * MPEG bitstreams could cause overread and segfault.
609 #define FF_INPUT_BUFFER_PADDING_SIZE 16
612 * @ingroup lavc_encoding
613 * minimum encoding buffer size
614 * Used to avoid some checks during header writing.
616 #define FF_MIN_BUFFER_SIZE 16384
620 * @ingroup lavc_encoding
621 * motion estimation type.
624 ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
628 ME_EPZS, ///< enhanced predictive zonal search
629 ME_X1, ///< reserved for experiments
630 ME_HEX, ///< hexagon based search
631 ME_UMH, ///< uneven multi-hexagon search
632 ME_TESA, ///< transformed exhaustive search algorithm
633 ME_ITER=50, ///< iterative search
637 * @ingroup lavc_decoding
640 /* We leave some space between them for extensions (drop some
641 * keyframes for intra-only or drop just some bidir frames). */
642 AVDISCARD_NONE =-16, ///< discard nothing
643 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
644 AVDISCARD_NONREF = 8, ///< discard all non reference
645 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
646 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
647 AVDISCARD_ALL = 48, ///< discard all
650 enum AVColorPrimaries{
651 AVCOL_PRI_BT709 = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 / SMPTE RP177 Annex B
652 AVCOL_PRI_UNSPECIFIED = 2,
653 AVCOL_PRI_BT470M = 4,
654 AVCOL_PRI_BT470BG = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
655 AVCOL_PRI_SMPTE170M = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
656 AVCOL_PRI_SMPTE240M = 7, ///< functionally identical to above
658 AVCOL_PRI_BT2020 = 9, ///< ITU-R BT2020
659 AVCOL_PRI_NB , ///< Not part of ABI
662 enum AVColorTransferCharacteristic{
663 AVCOL_TRC_BT709 = 1, ///< also ITU-R BT1361
664 AVCOL_TRC_UNSPECIFIED = 2,
665 AVCOL_TRC_GAMMA22 = 4, ///< also ITU-R BT470M / ITU-R BT1700 625 PAL & SECAM
666 AVCOL_TRC_GAMMA28 = 5, ///< also ITU-R BT470BG
667 AVCOL_TRC_SMPTE170M = 6, ///< also ITU-R BT601-6 525 or 625 / ITU-R BT1358 525 or 625 / ITU-R BT1700 NTSC
668 AVCOL_TRC_SMPTE240M = 7,
669 AVCOL_TRC_LINEAR = 8, ///< "Linear transfer characteristics"
670 AVCOL_TRC_LOG = 9, ///< "Logarithmic transfer characteristic (100:1 range)"
671 AVCOL_TRC_LOG_SQRT = 10, ///< "Logarithmic transfer characteristic (100 * Sqrt( 10 ) : 1 range)"
672 AVCOL_TRC_IEC61966_2_4 = 11, ///< IEC 61966-2-4
673 AVCOL_TRC_BT1361_ECG = 12, ///< ITU-R BT1361 Extended Colour Gamut
674 AVCOL_TRC_IEC61966_2_1 = 13, ///< IEC 61966-2-1 (sRGB or sYCC)
675 AVCOL_TRC_BT2020_10 = 14, ///< ITU-R BT2020 for 10 bit system
676 AVCOL_TRC_BT2020_12 = 15, ///< ITU-R BT2020 for 12 bit system
677 AVCOL_TRC_NB , ///< Not part of ABI
681 * X X 3 4 X X are luma samples,
682 * 1 2 1-6 are possible chroma positions
683 * X X 5 6 X 0 is undefined/unknown position
685 enum AVChromaLocation{
686 AVCHROMA_LOC_UNSPECIFIED = 0,
687 AVCHROMA_LOC_LEFT = 1, ///< mpeg2/4, h264 default
688 AVCHROMA_LOC_CENTER = 2, ///< mpeg1, jpeg, h263
689 AVCHROMA_LOC_TOPLEFT = 3, ///< DV
690 AVCHROMA_LOC_TOP = 4,
691 AVCHROMA_LOC_BOTTOMLEFT = 5,
692 AVCHROMA_LOC_BOTTOM = 6,
693 AVCHROMA_LOC_NB , ///< Not part of ABI
696 enum AVAudioServiceType {
697 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
698 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
699 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
700 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
701 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
702 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
703 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
704 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
705 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
706 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
710 * @ingroup lavc_encoding
712 typedef struct RcOverride{
715 int qscale; // If this is 0 then quality_factor will be used instead.
716 float quality_factor;
719 #if FF_API_MAX_BFRAMES
721 * @deprecated there is no libavcodec-wide limit on the number of B-frames
723 #define FF_MAX_B_FRAMES 16
727 These flags can be passed in AVCodecContext.flags before initialization.
728 Note: Not everything is supported yet.
732 * Allow decoders to produce frames with data planes that are not aligned
733 * to CPU requirements (e.g. due to cropping).
735 #define CODEC_FLAG_UNALIGNED 0x0001
736 #define CODEC_FLAG_QSCALE 0x0002 ///< Use fixed qscale.
737 #define CODEC_FLAG_4MV 0x0004 ///< 4 MV per MB allowed / advanced prediction for H.263.
738 #define CODEC_FLAG_OUTPUT_CORRUPT 0x0008 ///< Output even those frames that might be corrupted
739 #define CODEC_FLAG_QPEL 0x0010 ///< Use qpel MC.
740 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
741 #define CODEC_FLAG_MV0 0x0040 ///< Always try a MB with MV=<0,0>.
743 * The parent program guarantees that the input for B-frames containing
744 * streams is not written to for at least s->max_b_frames+1 frames, if
745 * this is not set the input will be copied.
747 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
748 #define CODEC_FLAG_PASS1 0x0200 ///< Use internal 2pass ratecontrol in first pass mode.
749 #define CODEC_FLAG_PASS2 0x0400 ///< Use internal 2pass ratecontrol in second pass mode.
750 #define CODEC_FLAG_GRAY 0x2000 ///< Only decode/encode grayscale.
753 * @deprecated edges are not used/required anymore. I.e. this flag is now always
756 #define CODEC_FLAG_EMU_EDGE 0x4000
758 #define CODEC_FLAG_PSNR 0x8000 ///< error[?] variables will be set during encoding.
759 #define CODEC_FLAG_TRUNCATED 0x00010000 /** Input bitstream might be truncated at a random
760 location instead of only at frame boundaries. */
761 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000 ///< Normalize adaptive quantization.
762 #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
763 #define CODEC_FLAG_LOW_DELAY 0x00080000 ///< Force low delay.
764 #define CODEC_FLAG_GLOBAL_HEADER 0x00400000 ///< Place global headers in extradata instead of every keyframe.
765 #define CODEC_FLAG_BITEXACT 0x00800000 ///< Use only bitexact stuff (except (I)DCT).
766 /* Fx : Flag for h263+ extra options */
767 #define CODEC_FLAG_AC_PRED 0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
768 #define CODEC_FLAG_LOOP_FILTER 0x00000800 ///< loop filter
769 #define CODEC_FLAG_INTERLACED_ME 0x20000000 ///< interlaced motion estimation
770 #define CODEC_FLAG_CLOSED_GOP 0x80000000
771 #define CODEC_FLAG2_FAST 0x00000001 ///< Allow non spec compliant speedup tricks.
772 #define CODEC_FLAG2_NO_OUTPUT 0x00000004 ///< Skip bitstream encoding.
773 #define CODEC_FLAG2_LOCAL_HEADER 0x00000008 ///< Place global headers at every keyframe instead of in extradata.
774 #define CODEC_FLAG2_DROP_FRAME_TIMECODE 0x00002000 ///< timecode is in drop frame format. DEPRECATED!!!!
775 #define CODEC_FLAG2_IGNORE_CROP 0x00010000 ///< Discard cropping information from SPS.
777 #define CODEC_FLAG2_CHUNKS 0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
778 #define CODEC_FLAG2_SHOW_ALL 0x00400000 ///< Show all frames before the first keyframe
780 /* Unsupported options :
781 * Syntax Arithmetic coding (SAC)
782 * Reference Picture Selection
783 * Independent Segment Decoding */
785 /* codec capabilities */
787 #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
789 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
790 * If not set, it might not use get_buffer() at all or use operations that
791 * assume the buffer was allocated by avcodec_default_get_buffer.
793 #define CODEC_CAP_DR1 0x0002
794 #define CODEC_CAP_TRUNCATED 0x0008
796 /* Codec can export data for HW decoding. This flag indicates that
797 * the codec would call get_format() with list that might contain HW accelerated
798 * pixel formats (XvMC, VDPAU, VAAPI, etc). The application can pick any of them
799 * including raw image format.
800 * The application can use the passed context to determine bitstream version,
801 * chroma format, resolution etc.
803 #define CODEC_CAP_HWACCEL 0x0010
804 #endif /* FF_API_XVMC */
806 * Encoder or decoder requires flushing with NULL input at the end in order to
807 * give the complete and correct output.
809 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
810 * with NULL data. The user can still send NULL data to the public encode
811 * or decode function, but libavcodec will not pass it along to the codec
812 * unless this flag is set.
815 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
816 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
820 * The encoder needs to be fed with NULL data at the end of encoding until the
821 * encoder no longer returns data.
823 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
824 * flag also means that the encoder must set the pts and duration for
825 * each output packet. If this flag is not set, the pts and duration will
826 * be determined by libavcodec from the input frame.
828 #define CODEC_CAP_DELAY 0x0020
830 * Codec can be fed a final frame with a smaller size.
831 * This can be used to prevent truncation of the last audio samples.
833 #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
836 * Codec can export data for HW decoding (VDPAU).
838 #define CODEC_CAP_HWACCEL_VDPAU 0x0080
841 * Codec can output multiple frames per AVPacket
842 * Normally demuxers return one frame at a time, demuxers which do not do
843 * are connected to a parser to split what they return into proper frames.
844 * This flag is reserved to the very rare category of codecs which have a
845 * bitstream that cannot be split into frames without timeconsuming
846 * operations like full decoding. Demuxers carring such bitstreams thus
847 * may return multiple frames in a packet. This has many disadvantages like
848 * prohibiting stream copy in many cases thus it should only be considered
851 #define CODEC_CAP_SUBFRAMES 0x0100
853 * Codec is experimental and is thus avoided in favor of non experimental
856 #define CODEC_CAP_EXPERIMENTAL 0x0200
858 * Codec should fill in channel configuration and samplerate instead of container
860 #define CODEC_CAP_CHANNEL_CONF 0x0400
861 #if FF_API_NEG_LINESIZES
863 * @deprecated no codecs use this capability
865 #define CODEC_CAP_NEG_LINESIZES 0x0800
868 * Codec supports frame-level multithreading.
870 #define CODEC_CAP_FRAME_THREADS 0x1000
872 * Codec supports slice-based (or partition-based) multithreading.
874 #define CODEC_CAP_SLICE_THREADS 0x2000
876 * Codec supports changed parameters at any point.
878 #define CODEC_CAP_PARAM_CHANGE 0x4000
880 * Codec supports avctx->thread_count == 0 (auto).
882 #define CODEC_CAP_AUTO_THREADS 0x8000
884 * Audio encoder supports receiving a different number of samples in each call.
886 #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
888 * Codec is intra only.
890 #define CODEC_CAP_INTRA_ONLY 0x40000000
894 #define CODEC_CAP_LOSSLESS 0x80000000
897 //The following defines may change, don't expect compatibility if you use them.
898 #define MB_TYPE_INTRA4x4 0x0001
899 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
900 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
901 #define MB_TYPE_16x16 0x0008
902 #define MB_TYPE_16x8 0x0010
903 #define MB_TYPE_8x16 0x0020
904 #define MB_TYPE_8x8 0x0040
905 #define MB_TYPE_INTERLACED 0x0080
906 #define MB_TYPE_DIRECT2 0x0100 //FIXME
907 #define MB_TYPE_ACPRED 0x0200
908 #define MB_TYPE_GMC 0x0400
909 #define MB_TYPE_SKIP 0x0800
910 #define MB_TYPE_P0L0 0x1000
911 #define MB_TYPE_P1L0 0x2000
912 #define MB_TYPE_P0L1 0x4000
913 #define MB_TYPE_P1L1 0x8000
914 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
915 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
916 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
917 #define MB_TYPE_QUANT 0x00010000
918 #define MB_TYPE_CBP 0x00020000
919 //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
924 * This specifies the area which should be displayed.
925 * Note there may be multiple such areas for one frame.
927 typedef struct AVPanScan{
930 * - encoding: Set by user.
931 * - decoding: Set by libavcodec.
936 * width and height in 1/16 pel
937 * - encoding: Set by user.
938 * - decoding: Set by libavcodec.
944 * position of the top left corner in 1/16 pel for up to 3 fields/frames
945 * - encoding: Set by user.
946 * - decoding: Set by libavcodec.
948 int16_t position[3][2];
951 #if FF_API_QSCALE_TYPE
952 #define FF_QSCALE_TYPE_MPEG1 0
953 #define FF_QSCALE_TYPE_MPEG2 1
954 #define FF_QSCALE_TYPE_H264 2
955 #define FF_QSCALE_TYPE_VP56 3
958 #if FF_API_GET_BUFFER
959 #define FF_BUFFER_TYPE_INTERNAL 1
960 #define FF_BUFFER_TYPE_USER 2 ///< direct rendering buffers (image is (de)allocated by user)
961 #define FF_BUFFER_TYPE_SHARED 4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
962 #define FF_BUFFER_TYPE_COPY 8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
964 #define FF_BUFFER_HINTS_VALID 0x01 // Buffer hints value is meaningful (if 0 ignore).
965 #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
966 #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
967 #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
971 * The decoder will keep a reference to the frame and may reuse it later.
973 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
976 * @defgroup lavc_packet AVPacket
978 * Types and functions for working with AVPacket.
981 enum AVPacketSideDataType {
983 AV_PKT_DATA_NEW_EXTRADATA,
986 * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
989 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
990 * s32le channel_count
991 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
992 * u64le channel_layout
993 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
995 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1000 AV_PKT_DATA_PARAM_CHANGE,
1003 * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1004 * structures with info about macroblocks relevant to splitting the
1005 * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1006 * That is, it does not necessarily contain info about all macroblocks,
1007 * as long as the distance between macroblocks in the info is smaller
1008 * than the target payload size.
1009 * Each MB info structure is 12 bytes, and is laid out as follows:
1011 * u32le bit offset from the start of the packet
1012 * u8 current quantizer at the start of the macroblock
1014 * u16le macroblock address within the GOB
1015 * u8 horizontal MV predictor
1016 * u8 vertical MV predictor
1017 * u8 horizontal MV predictor for block number 3
1018 * u8 vertical MV predictor for block number 3
1021 AV_PKT_DATA_H263_MB_INFO,
1024 * This side data should be associated with an audio stream and contains
1025 * ReplayGain information in form of the AVReplayGain struct.
1027 AV_PKT_DATA_REPLAYGAIN,
1030 * Recommmends skipping the specified number of samples
1032 * u32le number of samples to skip from start of this packet
1033 * u32le number of samples to skip from end of this packet
1034 * u8 reason for start skip
1035 * u8 reason for end skip (0=padding silence, 1=convergence)
1038 AV_PKT_DATA_SKIP_SAMPLES=70,
1041 * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1042 * the packet may contain "dual mono" audio specific to Japanese DTV
1043 * and if it is true, recommends only the selected channel to be used.
1045 * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1048 AV_PKT_DATA_JP_DUALMONO,
1051 * A list of zero terminated key/value strings. There is no end marker for
1052 * the list, so it is required to rely on the side data size to stop.
1054 AV_PKT_DATA_STRINGS_METADATA,
1057 * Subtitle event position
1065 AV_PKT_DATA_SUBTITLE_POSITION,
1068 * Data found in BlockAdditional element of matroska container. There is
1069 * no end marker for the data, so it is required to rely on the side data
1070 * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1073 AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL,
1076 * The optional first identifier line of a WebVTT cue.
1078 AV_PKT_DATA_WEBVTT_IDENTIFIER,
1081 * The optional settings (rendering instructions) that immediately
1082 * follow the timestamp specifier of a WebVTT cue.
1084 AV_PKT_DATA_WEBVTT_SETTINGS,
1087 * A list of zero terminated key/value strings. There is no end marker for
1088 * the list, so it is required to rely on the side data size to stop. This
1089 * side data includes updated metadata which appeared in the stream.
1091 AV_PKT_DATA_METADATA_UPDATE,
1094 typedef struct AVPacketSideData {
1097 enum AVPacketSideDataType type;
1101 * This structure stores compressed data. It is typically exported by demuxers
1102 * and then passed as input to decoders, or received as output from encoders and
1103 * then passed to muxers.
1105 * For video, it should typically contain one compressed frame. For audio it may
1106 * contain several compressed frames.
1108 * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1109 * ABI. Thus it may be allocated on stack and no new fields can be added to it
1110 * without libavcodec and libavformat major bump.
1112 * The semantics of data ownership depends on the buf or destruct (deprecated)
1113 * fields. If either is set, the packet data is dynamically allocated and is
1114 * valid indefinitely until av_free_packet() is called (which in turn calls
1115 * av_buffer_unref()/the destruct callback to free the data). If neither is set,
1116 * the packet data is typically backed by some static buffer somewhere and is
1117 * only valid for a limited time (e.g. until the next read call when demuxing).
1119 * The side data is always allocated with av_malloc() and is freed in
1122 typedef struct AVPacket {
1124 * A reference to the reference-counted buffer where the packet data is
1126 * May be NULL, then the packet data is not reference-counted.
1130 * Presentation timestamp in AVStream->time_base units; the time at which
1131 * the decompressed packet will be presented to the user.
1132 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1133 * pts MUST be larger or equal to dts as presentation cannot happen before
1134 * decompression, unless one wants to view hex dumps. Some formats misuse
1135 * the terms dts and pts/cts to mean something different. Such timestamps
1136 * must be converted to true pts/dts before they are stored in AVPacket.
1140 * Decompression timestamp in AVStream->time_base units; the time at which
1141 * the packet is decompressed.
1142 * Can be AV_NOPTS_VALUE if it is not stored in the file.
1149 * A combination of AV_PKT_FLAG values
1153 * Additional packet data that can be provided by the container.
1154 * Packet can contain several types of side information.
1156 AVPacketSideData *side_data;
1157 int side_data_elems;
1160 * Duration of this packet in AVStream->time_base units, 0 if unknown.
1161 * Equals next_pts - this_pts in presentation order.
1164 #if FF_API_DESTRUCT_PACKET
1165 attribute_deprecated
1166 void (*destruct)(struct AVPacket *);
1167 attribute_deprecated
1170 int64_t pos; ///< byte position in stream, -1 if unknown
1173 * Time difference in AVStream->time_base units from the pts of this
1174 * packet to the point at which the output from the decoder has converged
1175 * independent from the availability of previous frames. That is, the
1176 * frames are virtually identical no matter if decoding started from
1177 * the very first frame or from this keyframe.
1178 * Is AV_NOPTS_VALUE if unknown.
1179 * This field is not the display duration of the current packet.
1180 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
1183 * The purpose of this field is to allow seeking in streams that have no
1184 * keyframes in the conventional sense. It corresponds to the
1185 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
1186 * essential for some types of subtitle streams to ensure that all
1187 * subtitles are correctly displayed after seeking.
1189 int64_t convergence_duration;
1191 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1192 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1194 enum AVSideDataParamChangeFlags {
1195 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1196 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1197 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1198 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1204 struct AVCodecInternal;
1208 AV_FIELD_PROGRESSIVE,
1209 AV_FIELD_TT, //< Top coded_first, top displayed first
1210 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1211 AV_FIELD_TB, //< Top coded first, bottom displayed first
1212 AV_FIELD_BT, //< Bottom coded first, top displayed first
1216 * main external API structure.
1217 * New fields can be added to the end with minor version bumps.
1218 * Removal, reordering and changes to existing fields require a major
1220 * Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1222 * sizeof(AVCodecContext) must not be used outside libav*.
1224 typedef struct AVCodecContext {
1226 * information on struct for av_log
1227 * - set by avcodec_alloc_context3
1229 const AVClass *av_class;
1230 int log_level_offset;
1232 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1233 const struct AVCodec *codec;
1234 char codec_name[32];
1235 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1238 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1239 * This is used to work around some encoder bugs.
1240 * A demuxer should set this to what is stored in the field used to identify the codec.
1241 * If there are multiple such fields in a container then the demuxer should choose the one
1242 * which maximizes the information about the used codec.
1243 * If the codec tag field in a container is larger than 32 bits then the demuxer should
1244 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1245 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1247 * - encoding: Set by user, if not then the default based on codec_id will be used.
1248 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1250 unsigned int codec_tag;
1253 * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1254 * This is used to work around some encoder bugs.
1255 * - encoding: unused
1256 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1258 unsigned int stream_codec_tag;
1263 * Private context used for internal data.
1265 * Unlike priv_data, this is not codec-specific. It is used in general
1266 * libavcodec functions.
1268 struct AVCodecInternal *internal;
1271 * Private data of the user, can be used to carry app specific stuff.
1272 * - encoding: Set by user.
1273 * - decoding: Set by user.
1278 * the average bitrate
1279 * - encoding: Set by user; unused for constant quantizer encoding.
1280 * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
1285 * number of bits the bitstream is allowed to diverge from the reference.
1286 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1287 * - encoding: Set by user; unused for constant quantizer encoding.
1288 * - decoding: unused
1290 int bit_rate_tolerance;
1293 * Global quality for codecs which cannot change it per frame.
1294 * This should be proportional to MPEG-1/2/4 qscale.
1295 * - encoding: Set by user.
1296 * - decoding: unused
1301 * - encoding: Set by user.
1302 * - decoding: unused
1304 int compression_level;
1305 #define FF_COMPRESSION_DEFAULT -1
1309 * - encoding: Set by user.
1310 * - decoding: Set by user.
1316 * - encoding: Set by user.
1317 * - decoding: Set by user.
1322 * some codecs need / can use extradata like Huffman tables.
1323 * mjpeg: Huffman tables
1324 * rv10: additional flags
1325 * mpeg4: global headers (they can be in the bitstream or here)
1326 * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
1327 * than extradata_size to avoid problems if it is read with the bitstream reader.
1328 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1329 * - encoding: Set/allocated/freed by libavcodec.
1330 * - decoding: Set/allocated/freed by user.
1336 * This is the fundamental unit of time (in seconds) in terms
1337 * of which frame timestamps are represented. For fixed-fps content,
1338 * timebase should be 1/framerate and timestamp increments should be
1340 * - encoding: MUST be set by user.
1341 * - decoding: Set by libavcodec.
1343 AVRational time_base;
1346 * For some codecs, the time base is closer to the field rate than the frame rate.
1347 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1348 * if no telecine is used ...
1350 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1352 int ticks_per_frame;
1357 * Encoding: Number of frames delay there will be from the encoder input to
1358 * the decoder output. (we assume the decoder matches the spec)
1359 * Decoding: Number of frames delay in addition to what a standard decoder
1360 * as specified in the spec would produce.
1363 * Number of frames the decoded output will be delayed relative to the
1367 * For encoding, this is the number of "priming" samples added by the
1368 * encoder to the beginning of the stream. The decoded output will be
1369 * delayed by this many samples relative to the input to the encoder (or
1370 * more, if the decoder adds its own padding).
1371 * The timestamps on the output packets are adjusted by the encoder so
1372 * that they always refer to the first sample of the data actually
1373 * contained in the packet, including any added padding.
1374 * E.g. if the timebase is 1/samplerate and the timestamp of the first
1375 * input sample is 0, the timestamp of the first output packet will be
1378 * For decoding, this is the number of samples the decoder needs to
1379 * output before the decoder's output is valid. When seeking, you should
1380 * start decoding this many samples prior to your desired seek point.
1382 * - encoding: Set by libavcodec.
1383 * - decoding: Set by libavcodec.
1390 * picture width / height.
1391 * - encoding: MUST be set by user.
1392 * - decoding: May be set by the user before opening the decoder if known e.g.
1393 * from the container. Some decoders will require the dimensions
1394 * to be set by the caller. During decoding, the decoder may
1395 * overwrite those values as required.
1400 * Bitstream width / height, may be different from width/height e.g. when
1401 * the decoded frame is cropped before being output or lowres is enabled.
1402 * - encoding: unused
1403 * - decoding: May be set by the user before opening the decoder if known
1404 * e.g. from the container. During decoding, the decoder may
1405 * overwrite those values as required.
1407 int coded_width, coded_height;
1409 #if FF_API_ASPECT_EXTENDED
1410 #define FF_ASPECT_EXTENDED 15
1414 * the number of pictures in a group of pictures, or 0 for intra_only
1415 * - encoding: Set by user.
1416 * - decoding: unused
1421 * Pixel format, see AV_PIX_FMT_xxx.
1422 * May be set by the demuxer if known from headers.
1423 * May be overridden by the decoder if it knows better.
1424 * - encoding: Set by user.
1425 * - decoding: Set by user if known, overridden by libavcodec if known
1427 enum AVPixelFormat pix_fmt;
1430 * Motion estimation algorithm used for video coding.
1431 * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
1432 * 8 (umh), 9 (iter), 10 (tesa) [7, 8, 10 are x264 specific, 9 is snow specific]
1433 * - encoding: MUST be set by user.
1434 * - decoding: unused
1439 * If non NULL, 'draw_horiz_band' is called by the libavcodec
1440 * decoder to draw a horizontal band. It improves cache usage. Not
1441 * all codecs can do that. You must check the codec capabilities
1443 * When multithreading is used, it may be called from multiple threads
1444 * at the same time; threads might draw different parts of the same AVFrame,
1445 * or multiple AVFrames, and there is no guarantee that slices will be drawn
1447 * The function is also used by hardware acceleration APIs.
1448 * It is called at least once during frame decoding to pass
1449 * the data needed for hardware render.
1450 * In that mode instead of pixel data, AVFrame points to
1451 * a structure specific to the acceleration API. The application
1452 * reads the structure and can change some fields to indicate progress
1454 * - encoding: unused
1455 * - decoding: Set by user.
1456 * @param height the height of the slice
1457 * @param y the y position of the slice
1458 * @param type 1->top field, 2->bottom field, 3->frame
1459 * @param offset offset into the AVFrame.data from which the slice should be read
1461 void (*draw_horiz_band)(struct AVCodecContext *s,
1462 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1463 int y, int type, int height);
1466 * callback to negotiate the pixelFormat
1467 * @param fmt is the list of formats which are supported by the codec,
1468 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1469 * The first is always the native one.
1470 * @return the chosen format
1471 * - encoding: unused
1472 * - decoding: Set by user, if not set the native format will be chosen.
1474 enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1477 * maximum number of B-frames between non-B-frames
1478 * Note: The output will be delayed by max_b_frames+1 relative to the input.
1479 * - encoding: Set by user.
1480 * - decoding: unused
1485 * qscale factor between IP and B-frames
1486 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1487 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1488 * - encoding: Set by user.
1489 * - decoding: unused
1491 float b_quant_factor;
1493 /** obsolete FIXME remove */
1495 #define FF_RC_STRATEGY_XVID 1
1497 int b_frame_strategy;
1500 * qscale offset between IP and B-frames
1501 * - encoding: Set by user.
1502 * - decoding: unused
1504 float b_quant_offset;
1507 * Size of the frame reordering buffer in the decoder.
1508 * For MPEG-2 it is 1 IPB or 0 low delay IP.
1509 * - encoding: Set by libavcodec.
1510 * - decoding: Set by libavcodec.
1515 * 0-> h263 quant 1-> mpeg quant
1516 * - encoding: Set by user.
1517 * - decoding: unused
1522 * qscale factor between P and I-frames
1523 * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
1524 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1525 * - encoding: Set by user.
1526 * - decoding: unused
1528 float i_quant_factor;
1531 * qscale offset between P and I-frames
1532 * - encoding: Set by user.
1533 * - decoding: unused
1535 float i_quant_offset;
1538 * luminance masking (0-> disabled)
1539 * - encoding: Set by user.
1540 * - decoding: unused
1545 * temporary complexity masking (0-> disabled)
1546 * - encoding: Set by user.
1547 * - decoding: unused
1549 float temporal_cplx_masking;
1552 * spatial complexity masking (0-> disabled)
1553 * - encoding: Set by user.
1554 * - decoding: unused
1556 float spatial_cplx_masking;
1559 * p block masking (0-> disabled)
1560 * - encoding: Set by user.
1561 * - decoding: unused
1566 * darkness masking (0-> disabled)
1567 * - encoding: Set by user.
1568 * - decoding: unused
1574 * - encoding: Set by libavcodec.
1575 * - decoding: Set by user (or 0).
1579 * prediction method (needed for huffyuv)
1580 * - encoding: Set by user.
1581 * - decoding: unused
1583 int prediction_method;
1584 #define FF_PRED_LEFT 0
1585 #define FF_PRED_PLANE 1
1586 #define FF_PRED_MEDIAN 2
1589 * slice offsets in the frame in bytes
1590 * - encoding: Set/allocated by libavcodec.
1591 * - decoding: Set/allocated by user (or NULL).
1596 * sample aspect ratio (0 if unknown)
1597 * That is the width of a pixel divided by the height of the pixel.
1598 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1599 * - encoding: Set by user.
1600 * - decoding: Set by libavcodec.
1602 AVRational sample_aspect_ratio;
1605 * motion estimation comparison function
1606 * - encoding: Set by user.
1607 * - decoding: unused
1611 * subpixel motion estimation comparison function
1612 * - encoding: Set by user.
1613 * - decoding: unused
1617 * macroblock comparison function (not supported yet)
1618 * - encoding: Set by user.
1619 * - decoding: unused
1623 * interlaced DCT comparison function
1624 * - encoding: Set by user.
1625 * - decoding: unused
1628 #define FF_CMP_SAD 0
1629 #define FF_CMP_SSE 1
1630 #define FF_CMP_SATD 2
1631 #define FF_CMP_DCT 3
1632 #define FF_CMP_PSNR 4
1633 #define FF_CMP_BIT 5
1635 #define FF_CMP_ZERO 7
1636 #define FF_CMP_VSAD 8
1637 #define FF_CMP_VSSE 9
1638 #define FF_CMP_NSSE 10
1639 #define FF_CMP_W53 11
1640 #define FF_CMP_W97 12
1641 #define FF_CMP_DCTMAX 13
1642 #define FF_CMP_DCT264 14
1643 #define FF_CMP_CHROMA 256
1646 * ME diamond size & shape
1647 * - encoding: Set by user.
1648 * - decoding: unused
1653 * amount of previous MV predictors (2a+1 x 2a+1 square)
1654 * - encoding: Set by user.
1655 * - decoding: unused
1657 int last_predictor_count;
1660 * prepass for motion estimation
1661 * - encoding: Set by user.
1662 * - decoding: unused
1667 * motion estimation prepass comparison function
1668 * - encoding: Set by user.
1669 * - decoding: unused
1674 * ME prepass diamond size & shape
1675 * - encoding: Set by user.
1676 * - decoding: unused
1682 * - encoding: Set by user.
1683 * - decoding: unused
1685 int me_subpel_quality;
1688 * DTG active format information (additional aspect ratio
1689 * information only used in DVB MPEG-2 transport streams)
1692 * - encoding: unused
1693 * - decoding: Set by decoder.
1695 int dtg_active_format;
1696 #define FF_DTG_AFD_SAME 8
1697 #define FF_DTG_AFD_4_3 9
1698 #define FF_DTG_AFD_16_9 10
1699 #define FF_DTG_AFD_14_9 11
1700 #define FF_DTG_AFD_4_3_SP_14_9 13
1701 #define FF_DTG_AFD_16_9_SP_14_9 14
1702 #define FF_DTG_AFD_SP_4_3 15
1705 * maximum motion estimation search range in subpel units
1706 * If 0 then no limit.
1708 * - encoding: Set by user.
1709 * - decoding: unused
1714 * intra quantizer bias
1715 * - encoding: Set by user.
1716 * - decoding: unused
1718 int intra_quant_bias;
1719 #define FF_DEFAULT_QUANT_BIAS 999999
1722 * inter quantizer bias
1723 * - encoding: Set by user.
1724 * - decoding: unused
1726 int inter_quant_bias;
1730 * - encoding: unused
1731 * - decoding: Set by user.
1734 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1735 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
1736 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1740 * XVideo Motion Acceleration
1741 * - encoding: forbidden
1742 * - decoding: set by decoder
1743 * @deprecated XvMC doesn't need it anymore.
1745 attribute_deprecated int xvmc_acceleration;
1746 #endif /* FF_API_XVMC */
1749 * macroblock decision mode
1750 * - encoding: Set by user.
1751 * - decoding: unused
1754 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1755 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1756 #define FF_MB_DECISION_RD 2 ///< rate distortion
1759 * custom intra quantization matrix
1760 * - encoding: Set by user, can be NULL.
1761 * - decoding: Set by libavcodec.
1763 uint16_t *intra_matrix;
1766 * custom inter quantization matrix
1767 * - encoding: Set by user, can be NULL.
1768 * - decoding: Set by libavcodec.
1770 uint16_t *inter_matrix;
1773 * scene change detection threshold
1774 * 0 is default, larger means fewer detected scene changes.
1775 * - encoding: Set by user.
1776 * - decoding: unused
1778 int scenechange_threshold;
1781 * noise reduction strength
1782 * - encoding: Set by user.
1783 * - decoding: unused
1785 int noise_reduction;
1788 * Motion estimation threshold below which no motion estimation is
1789 * performed, but instead the user specified motion vectors are used.
1791 * - encoding: Set by user.
1792 * - decoding: unused
1797 * Macroblock threshold below which the user specified macroblock types will be used.
1798 * - encoding: Set by user.
1799 * - decoding: unused
1804 * precision of the intra DC coefficient - 8
1805 * - encoding: Set by user.
1806 * - decoding: unused
1808 int intra_dc_precision;
1811 * Number of macroblock rows at the top which are skipped.
1812 * - encoding: unused
1813 * - decoding: Set by user.
1818 * Number of macroblock rows at the bottom which are skipped.
1819 * - encoding: unused
1820 * - decoding: Set by user.
1825 * Border processing masking, raises the quantizer for mbs on the borders
1827 * - encoding: Set by user.
1828 * - decoding: unused
1830 float border_masking;
1833 * minimum MB lagrange multipler
1834 * - encoding: Set by user.
1835 * - decoding: unused
1840 * maximum MB lagrange multipler
1841 * - encoding: Set by user.
1842 * - decoding: unused
1848 * - encoding: Set by user.
1849 * - decoding: unused
1851 int me_penalty_compensation;
1855 * - encoding: Set by user.
1856 * - decoding: unused
1862 * - encoding: Set by user.
1863 * - decoding: unused
1869 * - encoding: Set by user.
1870 * - decoding: unused
1875 * number of reference frames
1876 * - encoding: Set by user.
1877 * - decoding: Set by lavc.
1882 * chroma qp offset from luma
1883 * - encoding: Set by user.
1884 * - decoding: unused
1889 * Multiplied by qscale for each frame and added to scene_change_score.
1890 * - encoding: Set by user.
1891 * - decoding: unused
1893 int scenechange_factor;
1897 * Note: Value depends upon the compare function used for fullpel ME.
1898 * - encoding: Set by user.
1899 * - decoding: unused
1904 * Adjust sensitivity of b_frame_strategy 1.
1905 * - encoding: Set by user.
1906 * - decoding: unused
1911 * Chromaticity coordinates of the source primaries.
1912 * - encoding: Set by user
1913 * - decoding: Set by libavcodec
1915 enum AVColorPrimaries color_primaries;
1918 * Color Transfer Characteristic.
1919 * - encoding: Set by user
1920 * - decoding: Set by libavcodec
1922 enum AVColorTransferCharacteristic color_trc;
1925 * YUV colorspace type.
1926 * - encoding: Set by user
1927 * - decoding: Set by libavcodec
1929 enum AVColorSpace colorspace;
1932 * MPEG vs JPEG YUV range.
1933 * - encoding: Set by user
1934 * - decoding: Set by libavcodec
1936 enum AVColorRange color_range;
1939 * This defines the location of chroma samples.
1940 * - encoding: Set by user
1941 * - decoding: Set by libavcodec
1943 enum AVChromaLocation chroma_sample_location;
1947 * Indicates number of picture subdivisions. Used for parallelized
1949 * - encoding: Set by user
1950 * - decoding: unused
1955 * - encoding: set by libavcodec
1956 * - decoding: Set by user.
1958 enum AVFieldOrder field_order;
1961 int sample_rate; ///< samples per second
1962 int channels; ///< number of audio channels
1965 * audio sample format
1966 * - encoding: Set by user.
1967 * - decoding: Set by libavcodec.
1969 enum AVSampleFormat sample_fmt; ///< sample format
1971 /* The following data should not be initialized. */
1973 * Number of samples per channel in an audio frame.
1975 * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1976 * except the last must contain exactly frame_size samples per channel.
1977 * May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1978 * frame size is not restricted.
1979 * - decoding: may be set by some decoders to indicate constant frame size
1984 * Frame counter, set by libavcodec.
1986 * - decoding: total number of frames returned from the decoder so far.
1987 * - encoding: total number of frames passed to the encoder so far.
1989 * @note the counter is not incremented if encoding/decoding resulted in
1995 * number of bytes per packet if constant and known or 0
1996 * Used by some WAV based audio codecs.
2001 * Audio cutoff bandwidth (0 means "automatic")
2002 * - encoding: Set by user.
2003 * - decoding: unused
2007 #if FF_API_REQUEST_CHANNELS
2009 * Decoder should decode to this many channels if it can (0 for default)
2010 * - encoding: unused
2011 * - decoding: Set by user.
2012 * @deprecated Deprecated in favor of request_channel_layout.
2014 attribute_deprecated int request_channels;
2018 * Audio channel layout.
2019 * - encoding: set by user.
2020 * - decoding: set by user, may be overwritten by libavcodec.
2022 uint64_t channel_layout;
2025 * Request decoder to use this channel layout if it can (0 for default)
2026 * - encoding: unused
2027 * - decoding: Set by user.
2029 uint64_t request_channel_layout;
2032 * Type of service that the audio stream conveys.
2033 * - encoding: Set by user.
2034 * - decoding: Set by libavcodec.
2036 enum AVAudioServiceType audio_service_type;
2039 * desired sample format
2040 * - encoding: Not used.
2041 * - decoding: Set by user.
2042 * Decoder will decode to this format if it can.
2044 enum AVSampleFormat request_sample_fmt;
2046 #if FF_API_GET_BUFFER
2048 * Called at the beginning of each frame to get a buffer for it.
2050 * The function will set AVFrame.data[], AVFrame.linesize[].
2051 * AVFrame.extended_data[] must also be set, but it should be the same as
2052 * AVFrame.data[] except for planar audio with more channels than can fit
2053 * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
2054 * many data pointers as it can hold.
2056 * if CODEC_CAP_DR1 is not set then get_buffer() must call
2057 * avcodec_default_get_buffer() instead of providing buffers allocated by
2060 * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
2061 * need it. avcodec_default_get_buffer() aligns the output buffer properly,
2062 * but if get_buffer() is overridden then alignment considerations should
2063 * be taken into account.
2065 * @see avcodec_default_get_buffer()
2069 * If pic.reference is set then the frame will be read later by libavcodec.
2070 * avcodec_align_dimensions2() should be used to find the required width and
2071 * height, as they normally need to be rounded up to the next multiple of 16.
2073 * If frame multithreading is used and thread_safe_callbacks is set,
2074 * it may be called from a different thread, but not from more than one at
2075 * once. Does not need to be reentrant.
2077 * @see release_buffer(), reget_buffer()
2078 * @see avcodec_align_dimensions2()
2082 * Decoders request a buffer of a particular size by setting
2083 * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
2084 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2085 * to a smaller value in the output frame.
2087 * Decoders cannot use the buffer after returning from
2088 * avcodec_decode_audio4(), so they will not call release_buffer(), as it
2089 * is assumed to be released immediately upon return. In some rare cases,
2090 * a decoder may need to call get_buffer() more than once in a single
2091 * call to avcodec_decode_audio4(). In that case, when get_buffer() is
2092 * called again after it has already been called once, the previously
2093 * acquired buffer is assumed to be released at that time and may not be
2094 * reused by the decoder.
2096 * As a convenience, av_samples_get_buffer_size() and
2097 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
2098 * functions to find the required data size and to fill data pointers and
2099 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2100 * since all planes must be the same size.
2102 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2104 * - encoding: unused
2105 * - decoding: Set by libavcodec, user can override.
2107 * @deprecated use get_buffer2()
2109 attribute_deprecated
2110 int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
2113 * Called to release buffers which were allocated with get_buffer.
2114 * A released buffer can be reused in get_buffer().
2115 * pic.data[*] must be set to NULL.
2116 * May be called from a different thread if frame multithreading is used,
2117 * but not by more than one thread at once, so does not need to be reentrant.
2118 * - encoding: unused
2119 * - decoding: Set by libavcodec, user can override.
2121 * @deprecated custom freeing callbacks should be set from get_buffer2()
2123 attribute_deprecated
2124 void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
2127 * Called at the beginning of a frame to get cr buffer for it.
2128 * Buffer type (size, hints) must be the same. libavcodec won't check it.
2129 * libavcodec will pass previous buffer in pic, function should return
2130 * same buffer or new buffer with old frame "painted" into it.
2131 * If pic.data[0] == NULL must behave like get_buffer().
2132 * if CODEC_CAP_DR1 is not set then reget_buffer() must call
2133 * avcodec_default_reget_buffer() instead of providing buffers allocated by
2135 * - encoding: unused
2136 * - decoding: Set by libavcodec, user can override.
2138 attribute_deprecated
2139 int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
2143 * This callback is called at the beginning of each frame to get data
2144 * buffer(s) for it. There may be one contiguous buffer for all the data or
2145 * there may be a buffer per each data plane or anything in between. What
2146 * this means is, you may set however many entries in buf[] you feel necessary.
2147 * Each buffer must be reference-counted using the AVBuffer API (see description
2150 * The following fields will be set in the frame before this callback is
2153 * - width, height (video only)
2154 * - sample_rate, channel_layout, nb_samples (audio only)
2155 * Their values may differ from the corresponding values in
2156 * AVCodecContext. This callback must use the frame values, not the codec
2157 * context values, to calculate the required buffer size.
2159 * This callback must fill the following fields in the frame:
2163 * * if the data is planar audio with more than 8 channels, then this
2164 * callback must allocate and fill extended_data to contain all pointers
2165 * to all data planes. data[] must hold as many pointers as it can.
2166 * extended_data must be allocated with av_malloc() and will be freed in
2168 * * otherwise exended_data must point to data
2169 * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2170 * the frame's data and extended_data pointers must be contained in these. That
2171 * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2172 * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2173 * and av_buffer_ref().
2174 * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2175 * this callback and filled with the extra buffers if there are more
2176 * buffers than buf[] can hold. extended_buf will be freed in
2179 * If CODEC_CAP_DR1 is not set then get_buffer2() must call
2180 * avcodec_default_get_buffer2() instead of providing buffers allocated by
2183 * Each data plane must be aligned to the maximum required by the target
2186 * @see avcodec_default_get_buffer2()
2190 * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2191 * (read and/or written to if it is writable) later by libavcodec.
2193 * avcodec_align_dimensions2() should be used to find the required width and
2194 * height, as they normally need to be rounded up to the next multiple of 16.
2196 * Some decoders do not support linesizes changing between frames.
2198 * If frame multithreading is used and thread_safe_callbacks is set,
2199 * this callback may be called from a different thread, but not from more
2200 * than one at once. Does not need to be reentrant.
2202 * @see avcodec_align_dimensions2()
2206 * Decoders request a buffer of a particular size by setting
2207 * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2208 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2209 * to a smaller value in the output frame.
2211 * As a convenience, av_samples_get_buffer_size() and
2212 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2213 * functions to find the required data size and to fill data pointers and
2214 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2215 * since all planes must be the same size.
2217 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2219 * - encoding: unused
2220 * - decoding: Set by libavcodec, user can override.
2222 int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2225 * If non-zero, the decoded audio and video frames returned from
2226 * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2227 * and are valid indefinitely. The caller must free them with
2228 * av_frame_unref() when they are not needed anymore.
2229 * Otherwise, the decoded frames must not be freed by the caller and are
2230 * only valid until the next decode call.
2232 * - encoding: unused
2233 * - decoding: set by the caller before avcodec_open2().
2235 int refcounted_frames;
2237 /* - encoding parameters */
2238 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2239 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2243 * - encoding: Set by user.
2244 * - decoding: unused
2250 * - encoding: Set by user.
2251 * - decoding: unused
2256 * maximum quantizer difference between frames
2257 * - encoding: Set by user.
2258 * - decoding: unused
2263 * ratecontrol qmin qmax limiting method
2264 * 0-> clipping, 1-> use a nice continuous function to limit qscale within qmin/qmax.
2265 * - encoding: Set by user.
2266 * - decoding: unused
2274 * decoder bitstream buffer size
2275 * - encoding: Set by user.
2276 * - decoding: unused
2281 * ratecontrol override, see RcOverride
2282 * - encoding: Allocated/set/freed by user.
2283 * - decoding: unused
2285 int rc_override_count;
2286 RcOverride *rc_override;
2289 * rate control equation
2290 * - encoding: Set by user
2291 * - decoding: unused
2297 * - encoding: Set by user.
2298 * - decoding: unused
2304 * - encoding: Set by user.
2305 * - decoding: unused
2309 float rc_buffer_aggressivity;
2312 * initial complexity for pass1 ratecontrol
2313 * - encoding: Set by user.
2314 * - decoding: unused
2316 float rc_initial_cplx;
2319 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2320 * - encoding: Set by user.
2321 * - decoding: unused.
2323 float rc_max_available_vbv_use;
2326 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2327 * - encoding: Set by user.
2328 * - decoding: unused.
2330 float rc_min_vbv_overflow_use;
2333 * Number of bits which should be loaded into the rc buffer before decoding starts.
2334 * - encoding: Set by user.
2335 * - decoding: unused
2337 int rc_initial_buffer_occupancy;
2339 #define FF_CODER_TYPE_VLC 0
2340 #define FF_CODER_TYPE_AC 1
2341 #define FF_CODER_TYPE_RAW 2
2342 #define FF_CODER_TYPE_RLE 3
2343 #define FF_CODER_TYPE_DEFLATE 4
2346 * - encoding: Set by user.
2347 * - decoding: unused
2353 * - encoding: Set by user.
2354 * - decoding: unused
2359 * minimum Lagrange multiplier
2360 * - encoding: Set by user.
2361 * - decoding: unused
2366 * maximum Lagrange multiplier
2367 * - encoding: Set by user.
2368 * - decoding: unused
2373 * frame skip threshold
2374 * - encoding: Set by user.
2375 * - decoding: unused
2377 int frame_skip_threshold;
2381 * - encoding: Set by user.
2382 * - decoding: unused
2384 int frame_skip_factor;
2387 * frame skip exponent
2388 * - encoding: Set by user.
2389 * - decoding: unused
2394 * frame skip comparison function
2395 * - encoding: Set by user.
2396 * - decoding: unused
2401 * trellis RD quantization
2402 * - encoding: Set by user.
2403 * - decoding: unused
2408 * - encoding: Set by user.
2409 * - decoding: unused
2411 int min_prediction_order;
2414 * - encoding: Set by user.
2415 * - decoding: unused
2417 int max_prediction_order;
2420 * GOP timecode frame start number
2421 * - encoding: Set by user, in non drop frame format
2422 * - decoding: Set by libavcodec (timecode in the 25 bits format, -1 if unset)
2424 int64_t timecode_frame_start;
2426 /* The RTP callback: This function is called */
2427 /* every time the encoder has a packet to send. */
2428 /* It depends on the encoder if the data starts */
2429 /* with a Start Code (it should). H.263 does. */
2430 /* mb_nb contains the number of macroblocks */
2431 /* encoded in the RTP payload. */
2432 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2434 int rtp_payload_size; /* The size of the RTP payload: the coder will */
2435 /* do its best to deliver a chunk with size */
2436 /* below rtp_payload_size, the chunk will start */
2437 /* with a start code on some codecs like H.263. */
2438 /* This doesn't take account of any particular */
2439 /* headers inside the transmitted RTP payload. */
2441 /* statistics, used for 2-pass encoding */
2452 * number of bits used for the previously encoded frame
2453 * - encoding: Set by libavcodec.
2454 * - decoding: unused
2459 * pass1 encoding statistics output buffer
2460 * - encoding: Set by libavcodec.
2461 * - decoding: unused
2466 * pass2 encoding statistics input buffer
2467 * Concatenated stuff from stats_out of pass1 should be placed here.
2468 * - encoding: Allocated/set/freed by user.
2469 * - decoding: unused
2474 * Work around bugs in encoders which sometimes cannot be detected automatically.
2475 * - encoding: Set by user
2476 * - decoding: Set by user
2478 int workaround_bugs;
2479 #define FF_BUG_AUTODETECT 1 ///< autodetection
2480 #if FF_API_OLD_MSMPEG4
2481 #define FF_BUG_OLD_MSMPEG4 2
2483 #define FF_BUG_XVID_ILACE 4
2484 #define FF_BUG_UMP4 8
2485 #define FF_BUG_NO_PADDING 16
2486 #define FF_BUG_AMV 32
2488 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2490 #define FF_BUG_QPEL_CHROMA 64
2491 #define FF_BUG_STD_QPEL 128
2492 #define FF_BUG_QPEL_CHROMA2 256
2493 #define FF_BUG_DIRECT_BLOCKSIZE 512
2494 #define FF_BUG_EDGE 1024
2495 #define FF_BUG_HPEL_CHROMA 2048
2496 #define FF_BUG_DC_CLIP 4096
2497 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2498 #define FF_BUG_TRUNCATED 16384
2501 * strictly follow the standard (MPEG4, ...).
2502 * - encoding: Set by user.
2503 * - decoding: Set by user.
2504 * Setting this to STRICT or higher means the encoder and decoder will
2505 * generally do stupid things, whereas setting it to unofficial or lower
2506 * will mean the encoder might produce output that is not supported by all
2507 * spec-compliant decoders. Decoders don't differentiate between normal,
2508 * unofficial and experimental (that is, they always try to decode things
2509 * when they can) unless they are explicitly asked to behave stupidly
2510 * (=strictly conform to the specs)
2512 int strict_std_compliance;
2513 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2514 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2515 #define FF_COMPLIANCE_NORMAL 0
2516 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2517 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2520 * error concealment flags
2521 * - encoding: unused
2522 * - decoding: Set by user.
2524 int error_concealment;
2525 #define FF_EC_GUESS_MVS 1
2526 #define FF_EC_DEBLOCK 2
2530 * - encoding: Set by user.
2531 * - decoding: Set by user.
2534 #define FF_DEBUG_PICT_INFO 1
2535 #define FF_DEBUG_RC 2
2536 #define FF_DEBUG_BITSTREAM 4
2537 #define FF_DEBUG_MB_TYPE 8
2538 #define FF_DEBUG_QP 16
2541 * @deprecated this option does nothing
2543 #define FF_DEBUG_MV 32
2545 #define FF_DEBUG_DCT_COEFF 0x00000040
2546 #define FF_DEBUG_SKIP 0x00000080
2547 #define FF_DEBUG_STARTCODE 0x00000100
2548 #define FF_DEBUG_PTS 0x00000200
2549 #define FF_DEBUG_ER 0x00000400
2550 #define FF_DEBUG_MMCO 0x00000800
2551 #define FF_DEBUG_BUGS 0x00001000
2553 #define FF_DEBUG_VIS_QP 0x00002000 ///< only access through AVOptions from outside libavcodec
2554 #define FF_DEBUG_VIS_MB_TYPE 0x00004000 ///< only access through AVOptions from outside libavcodec
2556 #define FF_DEBUG_BUFFERS 0x00008000
2557 #define FF_DEBUG_THREADS 0x00010000
2562 * Code outside libavcodec should access this field using AVOptions
2563 * - encoding: Set by user.
2564 * - decoding: Set by user.
2567 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2568 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2569 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2573 * Error recognition; may misdetect some more or less valid parts as errors.
2574 * - encoding: unused
2575 * - decoding: Set by user.
2577 int err_recognition;
2580 * Verify checksums embedded in the bitstream (could be of either encoded or
2581 * decoded data, depending on the codec) and print an error message on mismatch.
2582 * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2583 * decoder returning an error.
2585 #define AV_EF_CRCCHECK (1<<0)
2586 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2587 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2588 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2590 #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
2591 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2592 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2596 * opaque 64bit number (generally a PTS) that will be reordered and
2597 * output in AVFrame.reordered_opaque
2598 * @deprecated in favor of pkt_pts
2599 * - encoding: unused
2600 * - decoding: Set by user.
2602 int64_t reordered_opaque;
2605 * Hardware accelerator in use
2606 * - encoding: unused.
2607 * - decoding: Set by libavcodec
2609 struct AVHWAccel *hwaccel;
2612 * Hardware accelerator context.
2613 * For some hardware accelerators, a global context needs to be
2614 * provided by the user. In that case, this holds display-dependent
2615 * data FFmpeg cannot instantiate itself. Please refer to the
2616 * FFmpeg HW accelerator documentation to know how to fill this
2617 * is. e.g. for VA API, this is a struct vaapi_context.
2618 * - encoding: unused
2619 * - decoding: Set by user
2621 void *hwaccel_context;
2625 * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
2626 * - decoding: unused
2628 uint64_t error[AV_NUM_DATA_POINTERS];
2631 * DCT algorithm, see FF_DCT_* below
2632 * - encoding: Set by user.
2633 * - decoding: unused
2636 #define FF_DCT_AUTO 0
2637 #define FF_DCT_FASTINT 1
2638 #define FF_DCT_INT 2
2639 #define FF_DCT_MMX 3
2640 #define FF_DCT_ALTIVEC 5
2641 #define FF_DCT_FAAN 6
2644 * IDCT algorithm, see FF_IDCT_* below.
2645 * - encoding: Set by user.
2646 * - decoding: Set by user.
2649 #define FF_IDCT_AUTO 0
2650 #define FF_IDCT_INT 1
2651 #define FF_IDCT_SIMPLE 2
2652 #define FF_IDCT_SIMPLEMMX 3
2653 #define FF_IDCT_ARM 7
2654 #define FF_IDCT_ALTIVEC 8
2656 #define FF_IDCT_SH4 9
2658 #define FF_IDCT_SIMPLEARM 10
2659 #define FF_IDCT_IPP 13
2660 #define FF_IDCT_XVIDMMX 14
2661 #define FF_IDCT_SIMPLEARMV5TE 16
2662 #define FF_IDCT_SIMPLEARMV6 17
2663 #if FF_API_ARCH_SPARC
2664 #define FF_IDCT_SIMPLEVIS 18
2666 #define FF_IDCT_FAAN 20
2667 #define FF_IDCT_SIMPLENEON 22
2668 #if FF_API_ARCH_ALPHA
2669 #define FF_IDCT_SIMPLEALPHA 23
2673 * bits per sample/pixel from the demuxer (needed for huffyuv).
2674 * - encoding: Set by libavcodec.
2675 * - decoding: Set by user.
2677 int bits_per_coded_sample;
2680 * Bits per sample/pixel of internal libavcodec pixel/sample format.
2681 * - encoding: set by user.
2682 * - decoding: set by libavcodec.
2684 int bits_per_raw_sample;
2688 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2689 * - encoding: unused
2690 * - decoding: Set by user.
2691 * Code outside libavcodec should access this field using:
2692 * av_codec_{get,set}_lowres(avctx)
2698 * the picture in the bitstream
2699 * - encoding: Set by libavcodec.
2700 * - decoding: unused
2702 AVFrame *coded_frame;
2706 * is used to decide how many independent tasks should be passed to execute()
2707 * - encoding: Set by user.
2708 * - decoding: Set by user.
2713 * Which multithreading methods to use.
2714 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2715 * so clients which cannot provide future frames should not use it.
2717 * - encoding: Set by user, otherwise the default is used.
2718 * - decoding: Set by user, otherwise the default is used.
2721 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2722 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2725 * Which multithreading methods are in use by the codec.
2726 * - encoding: Set by libavcodec.
2727 * - decoding: Set by libavcodec.
2729 int active_thread_type;
2732 * Set by the client if its custom get_buffer() callback can be called
2733 * synchronously from another thread, which allows faster multithreaded decoding.
2734 * draw_horiz_band() will be called from other threads regardless of this setting.
2735 * Ignored if the default get_buffer() is used.
2736 * - encoding: Set by user.
2737 * - decoding: Set by user.
2739 int thread_safe_callbacks;
2742 * The codec may call this to execute several independent things.
2743 * It will return only after finishing all tasks.
2744 * The user may replace this with some multithreaded implementation,
2745 * the default implementation will execute the parts serially.
2746 * @param count the number of things to execute
2747 * - encoding: Set by libavcodec, user can override.
2748 * - decoding: Set by libavcodec, user can override.
2750 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2753 * The codec may call this to execute several independent things.
2754 * It will return only after finishing all tasks.
2755 * The user may replace this with some multithreaded implementation,
2756 * the default implementation will execute the parts serially.
2757 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2758 * @param c context passed also to func
2759 * @param count the number of things to execute
2760 * @param arg2 argument passed unchanged to func
2761 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2762 * @param func function that will be called count times, with jobnr from 0 to count-1.
2763 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2764 * two instances of func executing at the same time will have the same threadnr.
2765 * @return always 0 currently, but code should handle a future improvement where when any call to func
2766 * returns < 0 no further calls to func may be done and < 0 is returned.
2767 * - encoding: Set by libavcodec, user can override.
2768 * - decoding: Set by libavcodec, user can override.
2770 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2772 #if FF_API_THREAD_OPAQUE
2774 * @deprecated this field should not be used from outside of lavc
2776 attribute_deprecated
2777 void *thread_opaque;
2781 * noise vs. sse weight for the nsse comparison function
2782 * - encoding: Set by user.
2783 * - decoding: unused
2789 * - encoding: Set by user.
2790 * - decoding: Set by libavcodec.
2793 #define FF_PROFILE_UNKNOWN -99
2794 #define FF_PROFILE_RESERVED -100
2796 #define FF_PROFILE_AAC_MAIN 0
2797 #define FF_PROFILE_AAC_LOW 1
2798 #define FF_PROFILE_AAC_SSR 2
2799 #define FF_PROFILE_AAC_LTP 3
2800 #define FF_PROFILE_AAC_HE 4
2801 #define FF_PROFILE_AAC_HE_V2 28
2802 #define FF_PROFILE_AAC_LD 22
2803 #define FF_PROFILE_AAC_ELD 38
2804 #define FF_PROFILE_MPEG2_AAC_LOW 128
2805 #define FF_PROFILE_MPEG2_AAC_HE 131
2807 #define FF_PROFILE_DTS 20
2808 #define FF_PROFILE_DTS_ES 30
2809 #define FF_PROFILE_DTS_96_24 40
2810 #define FF_PROFILE_DTS_HD_HRA 50
2811 #define FF_PROFILE_DTS_HD_MA 60
2813 #define FF_PROFILE_MPEG2_422 0
2814 #define FF_PROFILE_MPEG2_HIGH 1
2815 #define FF_PROFILE_MPEG2_SS 2
2816 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2817 #define FF_PROFILE_MPEG2_MAIN 4
2818 #define FF_PROFILE_MPEG2_SIMPLE 5
2820 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2821 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2823 #define FF_PROFILE_H264_BASELINE 66
2824 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2825 #define FF_PROFILE_H264_MAIN 77
2826 #define FF_PROFILE_H264_EXTENDED 88
2827 #define FF_PROFILE_H264_HIGH 100
2828 #define FF_PROFILE_H264_HIGH_10 110
2829 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2830 #define FF_PROFILE_H264_HIGH_422 122
2831 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2832 #define FF_PROFILE_H264_HIGH_444 144
2833 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2834 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2835 #define FF_PROFILE_H264_CAVLC_444 44
2837 #define FF_PROFILE_VC1_SIMPLE 0
2838 #define FF_PROFILE_VC1_MAIN 1
2839 #define FF_PROFILE_VC1_COMPLEX 2
2840 #define FF_PROFILE_VC1_ADVANCED 3
2842 #define FF_PROFILE_MPEG4_SIMPLE 0
2843 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2844 #define FF_PROFILE_MPEG4_CORE 2
2845 #define FF_PROFILE_MPEG4_MAIN 3
2846 #define FF_PROFILE_MPEG4_N_BIT 4
2847 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2848 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2849 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2850 #define FF_PROFILE_MPEG4_HYBRID 8
2851 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2852 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2853 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2854 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2855 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2856 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2857 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2859 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 0
2860 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 1
2861 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 2
2862 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2863 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2866 #define FF_PROFILE_HEVC_MAIN 1
2867 #define FF_PROFILE_HEVC_MAIN_10 2
2868 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2872 * - encoding: Set by user.
2873 * - decoding: Set by libavcodec.
2876 #define FF_LEVEL_UNKNOWN -99
2879 * Skip loop filtering for selected frames.
2880 * - encoding: unused
2881 * - decoding: Set by user.
2883 enum AVDiscard skip_loop_filter;
2886 * Skip IDCT/dequantization for selected frames.
2887 * - encoding: unused
2888 * - decoding: Set by user.
2890 enum AVDiscard skip_idct;
2893 * Skip decoding for selected frames.
2894 * - encoding: unused
2895 * - decoding: Set by user.
2897 enum AVDiscard skip_frame;
2900 * Header containing style information for text subtitles.
2901 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2902 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2903 * the Format line following. It shouldn't include any Dialogue line.
2904 * - encoding: Set/allocated/freed by user (before avcodec_open2())
2905 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2907 uint8_t *subtitle_header;
2908 int subtitle_header_size;
2910 #if FF_API_ERROR_RATE
2912 * @deprecated use the 'error_rate' private AVOption of the mpegvideo
2915 attribute_deprecated
2919 #if FF_API_CODEC_PKT
2921 * @deprecated this field is not supposed to be accessed from outside lavc
2923 attribute_deprecated
2928 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2929 * Used for compliant TS muxing.
2930 * - encoding: Set by libavcodec.
2931 * - decoding: unused.
2936 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2937 * Code outside libavcodec should access this field using:
2938 * av_codec_{get,set}_pkt_timebase(avctx)
2939 * - encoding unused.
2940 * - decoding set by user.
2942 AVRational pkt_timebase;
2946 * Code outside libavcodec should access this field using:
2947 * av_codec_{get,set}_codec_descriptor(avctx)
2948 * - encoding: unused.
2949 * - decoding: set by libavcodec.
2951 const AVCodecDescriptor *codec_descriptor;
2955 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2956 * - encoding: unused
2957 * - decoding: Set by user.
2958 * Code outside libavcodec should access this field using:
2959 * av_codec_{get,set}_lowres(avctx)
2965 * Current statistics for PTS correction.
2966 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
2967 * - encoding: unused
2969 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
2970 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
2971 int64_t pts_correction_last_pts; /// PTS of the last frame
2972 int64_t pts_correction_last_dts; /// DTS of the last frame
2975 * Character encoding of the input subtitles file.
2976 * - decoding: set by user
2977 * - encoding: unused
2982 * Subtitles character encoding mode. Formats or codecs might be adjusting
2983 * this setting (if they are doing the conversion themselves for instance).
2984 * - decoding: set by libavcodec
2985 * - encoding: unused
2987 int sub_charenc_mode;
2988 #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)
2989 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
2990 #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
2993 * Skip processing alpha if supported by codec.
2994 * Note that if the format uses pre-multiplied alpha (common with VP6,
2995 * and recommended due to better video quality/compression)
2996 * the image will look as if alpha-blended onto a black background.
2997 * However for formats that do not use pre-multiplied alpha
2998 * there might be serious artefacts (though e.g. libswscale currently
2999 * assumes pre-multiplied alpha anyway).
3000 * Code outside libavcodec should access this field using AVOptions
3002 * - decoding: set by user
3003 * - encoding: unused
3008 * Number of samples to skip after a discontinuity
3009 * - decoding: unused
3010 * - encoding: set by libavcodec
3014 #if !FF_API_DEBUG_MV
3016 * debug motion vectors
3017 * Code outside libavcodec should access this field using AVOptions
3018 * - encoding: Set by user.
3019 * - decoding: Set by user.
3022 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3023 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3024 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3028 * custom intra quantization matrix
3029 * Code outside libavcodec should access this field using av_codec_g/set_chroma_intra_matrix()
3030 * - encoding: Set by user, can be NULL.
3031 * - decoding: unused.
3033 uint16_t *chroma_intra_matrix;
3036 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
3037 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
3039 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
3040 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
3042 int av_codec_get_lowres(const AVCodecContext *avctx);
3043 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3045 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3046 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3048 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3049 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3054 typedef struct AVProfile {
3056 const char *name; ///< short name for the profile
3059 typedef struct AVCodecDefault AVCodecDefault;
3066 typedef struct AVCodec {
3068 * Name of the codec implementation.
3069 * The name is globally unique among encoders and among decoders (but an
3070 * encoder and a decoder can share the same name).
3071 * This is the primary way to find a codec from the user perspective.
3075 * Descriptive name for the codec, meant to be more human readable than name.
3076 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3078 const char *long_name;
3079 enum AVMediaType type;
3082 * Codec capabilities.
3086 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3087 const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3088 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3089 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3090 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3092 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder, no direct access, use av_codec_get_max_lowres()
3094 const AVClass *priv_class; ///< AVClass for the private context
3095 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3097 /*****************************************************************
3098 * No fields below this line are part of the public API. They
3099 * may not be used outside of libavcodec and can be changed and
3101 * New public fields should be added right above.
3102 *****************************************************************
3105 struct AVCodec *next;
3107 * @name Frame-level threading support functions
3111 * If defined, called on thread contexts when they are created.
3112 * If the codec allocates writable tables in init(), re-allocate them here.
3113 * priv_data will be set to a copy of the original.
3115 int (*init_thread_copy)(AVCodecContext *);
3117 * Copy necessary context variables from a previous thread context to the current one.
3118 * If not defined, the next thread will start automatically; otherwise, the codec
3119 * must call ff_thread_finish_setup().
3121 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3123 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
3127 * Private codec-specific defaults.
3129 const AVCodecDefault *defaults;
3132 * Initialize codec static data, called from avcodec_register().
3134 void (*init_static_data)(struct AVCodec *codec);
3136 int (*init)(AVCodecContext *);
3137 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3138 const struct AVSubtitle *sub);
3140 * Encode data to an AVPacket.
3142 * @param avctx codec context
3143 * @param avpkt output AVPacket (may contain a user-provided buffer)
3144 * @param[in] frame AVFrame containing the raw data to be encoded
3145 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3146 * non-empty packet was returned in avpkt.
3147 * @return 0 on success, negative error code on failure
3149 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3150 int *got_packet_ptr);
3151 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3152 int (*close)(AVCodecContext *);
3155 * Will be called when seeking
3157 void (*flush)(AVCodecContext *);
3160 int av_codec_get_max_lowres(const AVCodec *codec);
3162 struct MpegEncContext;
3167 typedef struct AVHWAccel {
3169 * Name of the hardware accelerated codec.
3170 * The name is globally unique among encoders and among decoders (but an
3171 * encoder and a decoder can share the same name).
3176 * Type of codec implemented by the hardware accelerator.
3178 * See AVMEDIA_TYPE_xxx
3180 enum AVMediaType type;
3183 * Codec implemented by the hardware accelerator.
3185 * See AV_CODEC_ID_xxx
3190 * Supported pixel format.
3192 * Only hardware accelerated formats are supported here.
3194 enum AVPixelFormat pix_fmt;
3197 * Hardware accelerated codec capabilities.
3198 * see FF_HWACCEL_CODEC_CAP_*
3202 struct AVHWAccel *next;
3205 * Called at the beginning of each frame or field picture.
3207 * Meaningful frame information (codec specific) is guaranteed to
3208 * be parsed at this point. This function is mandatory.
3210 * Note that buf can be NULL along with buf_size set to 0.
3211 * Otherwise, this means the whole frame is available at this point.
3213 * @param avctx the codec context
3214 * @param buf the frame data buffer base
3215 * @param buf_size the size of the frame in bytes
3216 * @return zero if successful, a negative value otherwise
3218 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3221 * Callback for each slice.
3223 * Meaningful slice information (codec specific) is guaranteed to
3224 * be parsed at this point. This function is mandatory.
3225 * The only exception is XvMC, that works on MB level.
3227 * @param avctx the codec context
3228 * @param buf the slice data buffer base
3229 * @param buf_size the size of the slice in bytes
3230 * @return zero if successful, a negative value otherwise
3232 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3235 * Called at the end of each frame or field picture.
3237 * The whole picture is parsed at this point and can now be sent
3238 * to the hardware accelerator. This function is mandatory.
3240 * @param avctx the codec context
3241 * @return zero if successful, a negative value otherwise
3243 int (*end_frame)(AVCodecContext *avctx);
3246 * Size of HW accelerator private data.
3248 * Private data is allocated with av_mallocz() before
3249 * AVCodecContext.get_buffer() and deallocated after
3250 * AVCodecContext.release_buffer().
3255 * Called for every Macroblock in a slice.
3257 * XvMC uses it to replace the ff_MPV_decode_mb().
3258 * Instead of decoding to raw picture, MB parameters are
3259 * stored in an array provided by the video driver.
3261 * @param s the mpeg context
3263 void (*decode_mb)(struct MpegEncContext *s);
3267 * @defgroup lavc_picture AVPicture
3269 * Functions for working with AVPicture
3274 * Picture data structure.
3276 * Up to four components can be stored into it, the last component is
3279 typedef struct AVPicture {
3280 uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3281 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3288 enum AVSubtitleType {
3291 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3294 * Plain text, the text field must be set by the decoder and is
3295 * authoritative. ass and pict fields may contain approximations.
3300 * Formatted text, the ass field must be set by the decoder and is
3301 * authoritative. pict and text fields may contain approximations.
3306 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3308 typedef struct AVSubtitleRect {
3309 int x; ///< top left corner of pict, undefined when pict is not set
3310 int y; ///< top left corner of pict, undefined when pict is not set
3311 int w; ///< width of pict, undefined when pict is not set
3312 int h; ///< height of pict, undefined when pict is not set
3313 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3316 * data+linesize for the bitmap of this subtitle.
3317 * can be set for text/ass as well once they where rendered
3320 enum AVSubtitleType type;
3322 char *text; ///< 0 terminated plain UTF-8 text
3325 * 0 terminated ASS/SSA compatible event line.
3326 * The presentation of this is unaffected by the other values in this
3334 typedef struct AVSubtitle {
3335 uint16_t format; /* 0 = graphics */
3336 uint32_t start_display_time; /* relative to packet pts, in ms */
3337 uint32_t end_display_time; /* relative to packet pts, in ms */
3339 AVSubtitleRect **rects;
3340 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3344 * If c is NULL, returns the first registered codec,
3345 * if c is non-NULL, returns the next registered codec after c,
3346 * or NULL if c is the last one.
3348 AVCodec *av_codec_next(const AVCodec *c);
3351 * Return the LIBAVCODEC_VERSION_INT constant.
3353 unsigned avcodec_version(void);
3356 * Return the libavcodec build-time configuration.
3358 const char *avcodec_configuration(void);
3361 * Return the libavcodec license.
3363 const char *avcodec_license(void);
3366 * Register the codec codec and initialize libavcodec.
3368 * @warning either this function or avcodec_register_all() must be called
3369 * before any other libavcodec functions.
3371 * @see avcodec_register_all()
3373 void avcodec_register(AVCodec *codec);
3376 * Register all the codecs, parsers and bitstream filters which were enabled at
3377 * configuration time. If you do not call this function you can select exactly
3378 * which formats you want to support, by using the individual registration
3381 * @see avcodec_register
3382 * @see av_register_codec_parser
3383 * @see av_register_bitstream_filter
3385 void avcodec_register_all(void);
3388 * Allocate an AVCodecContext and set its fields to default values. The
3389 * resulting struct can be deallocated by calling avcodec_close() on it followed
3392 * @param codec if non-NULL, allocate private data and initialize defaults
3393 * for the given codec. It is illegal to then call avcodec_open2()
3394 * with a different codec.
3395 * If NULL, then the codec-specific defaults won't be initialized,
3396 * which may result in suboptimal default settings (this is
3397 * important mainly for encoders, e.g. libx264).
3399 * @return An AVCodecContext filled with default values or NULL on failure.
3400 * @see avcodec_get_context_defaults
3402 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3405 * Set the fields of the given AVCodecContext to default values corresponding
3406 * to the given codec (defaults may be codec-dependent).
3408 * Do not call this function if a non-NULL codec has been passed
3409 * to avcodec_alloc_context3() that allocated this AVCodecContext.
3410 * If codec is non-NULL, it is illegal to call avcodec_open2() with a
3411 * different codec on this AVCodecContext.
3413 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3416 * Get the AVClass for AVCodecContext. It can be used in combination with
3417 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3419 * @see av_opt_find().
3421 const AVClass *avcodec_get_class(void);
3424 * Get the AVClass for AVFrame. It can be used in combination with
3425 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3427 * @see av_opt_find().
3429 const AVClass *avcodec_get_frame_class(void);
3432 * Get the AVClass for AVSubtitleRect. It can be used in combination with
3433 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3435 * @see av_opt_find().
3437 const AVClass *avcodec_get_subtitle_rect_class(void);
3440 * Copy the settings of the source AVCodecContext into the destination
3441 * AVCodecContext. The resulting destination codec context will be
3442 * unopened, i.e. you are required to call avcodec_open2() before you
3443 * can use this AVCodecContext to decode/encode video/audio data.
3445 * @param dest target codec context, should be initialized with
3446 * avcodec_alloc_context3(NULL), but otherwise uninitialized
3447 * @param src source codec context
3448 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3450 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3452 #if FF_API_AVFRAME_LAVC
3454 * @deprecated use av_frame_alloc()
3456 attribute_deprecated
3457 AVFrame *avcodec_alloc_frame(void);
3460 * Set the fields of the given AVFrame to default values.
3462 * @param frame The AVFrame of which the fields should be set to default values.
3464 * @deprecated use av_frame_unref()
3466 attribute_deprecated
3467 void avcodec_get_frame_defaults(AVFrame *frame);
3470 * Free the frame and any dynamically allocated objects in it,
3471 * e.g. extended_data.
3473 * @param frame frame to be freed. The pointer will be set to NULL.
3475 * @warning this function does NOT free the data buffers themselves
3476 * (it does not know how, since they might have been allocated with
3477 * a custom get_buffer()).
3479 * @deprecated use av_frame_free()
3481 attribute_deprecated
3482 void avcodec_free_frame(AVFrame **frame);
3486 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3487 * function the context has to be allocated with avcodec_alloc_context3().
3489 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3490 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3491 * retrieving a codec.
3493 * @warning This function is not thread safe!
3496 * avcodec_register_all();
3497 * av_dict_set(&opts, "b", "2.5M", 0);
3498 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3502 * context = avcodec_alloc_context3(codec);
3504 * if (avcodec_open2(context, codec, opts) < 0)
3508 * @param avctx The context to initialize.
3509 * @param codec The codec to open this context for. If a non-NULL codec has been
3510 * previously passed to avcodec_alloc_context3() or
3511 * avcodec_get_context_defaults3() for this context, then this
3512 * parameter MUST be either NULL or equal to the previously passed
3514 * @param options A dictionary filled with AVCodecContext and codec-private options.
3515 * On return this object will be filled with options that were not found.
3517 * @return zero on success, a negative value on error
3518 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3519 * av_dict_set(), av_opt_find().
3521 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3524 * Close a given AVCodecContext and free all the data associated with it
3525 * (but not the AVCodecContext itself).
3527 * Calling this function on an AVCodecContext that hasn't been opened will free
3528 * the codec-specific data allocated in avcodec_alloc_context3() /
3529 * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
3532 int avcodec_close(AVCodecContext *avctx);
3535 * Free all allocated data in the given subtitle struct.
3537 * @param sub AVSubtitle to free.
3539 void avsubtitle_free(AVSubtitle *sub);
3546 * @addtogroup lavc_packet
3550 #if FF_API_DESTRUCT_PACKET
3552 * Default packet destructor.
3553 * @deprecated use the AVBuffer API instead
3555 attribute_deprecated
3556 void av_destruct_packet(AVPacket *pkt);
3560 * Initialize optional fields of a packet with default values.
3562 * Note, this does not touch the data and size members, which have to be
3563 * initialized separately.
3567 void av_init_packet(AVPacket *pkt);
3570 * Allocate the payload of a packet and initialize its fields with
3574 * @param size wanted payload size
3575 * @return 0 if OK, AVERROR_xxx otherwise
3577 int av_new_packet(AVPacket *pkt, int size);
3580 * Reduce packet size, correctly zeroing padding
3583 * @param size new size
3585 void av_shrink_packet(AVPacket *pkt, int size);
3588 * Increase packet size, correctly zeroing padding
3591 * @param grow_by number of bytes by which to increase the size of the packet
3593 int av_grow_packet(AVPacket *pkt, int grow_by);
3596 * Initialize a reference-counted packet from av_malloc()ed data.
3598 * @param pkt packet to be initialized. This function will set the data, size,
3599 * buf and destruct fields, all others are left untouched.
3600 * @param data Data allocated by av_malloc() to be used as packet data. If this
3601 * function returns successfully, the data is owned by the underlying AVBuffer.
3602 * The caller may not access the data through other means.
3603 * @param size size of data in bytes, without the padding. I.e. the full buffer
3604 * size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
3606 * @return 0 on success, a negative AVERROR on error
3608 int av_packet_from_data(AVPacket *pkt, uint8_t *data, int size);
3611 * @warning This is a hack - the packet memory allocation stuff is broken. The
3612 * packet is allocated if it was not really allocated.
3614 int av_dup_packet(AVPacket *pkt);
3617 * Copy packet, including contents
3619 * @return 0 on success, negative AVERROR on fail
3621 int av_copy_packet(AVPacket *dst, const AVPacket *src);
3624 * Copy packet side data
3626 * @return 0 on success, negative AVERROR on fail
3628 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
3633 * @param pkt packet to free
3635 void av_free_packet(AVPacket *pkt);
3638 * Allocate new information of a packet.
3641 * @param type side information type
3642 * @param size side information size
3643 * @return pointer to fresh allocated data or NULL otherwise
3645 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3649 * Shrink the already allocated side data buffer
3652 * @param type side information type
3653 * @param size new side information size
3654 * @return 0 on success, < 0 on failure
3656 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3660 * Get side information from packet.
3663 * @param type desired side information type
3664 * @param size pointer for side information size to store (optional)
3665 * @return pointer to data if present or NULL otherwise
3667 uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3670 int av_packet_merge_side_data(AVPacket *pkt);
3672 int av_packet_split_side_data(AVPacket *pkt);
3675 * Pack a dictionary for use in side_data.
3677 * @param dict The dictionary to pack.
3678 * @param size pointer to store the size of the returned data
3679 * @return pointer to data if successful, NULL otherwise
3681 uint8_t *av_packet_pack_dictionary(AVDictionary *dict, int *size);
3683 * Unpack a dictionary from side_data.
3685 * @param data data from side_data
3686 * @param size size of the data
3687 * @param dict the metadata storage dictionary
3688 * @return 0 on success, < 0 on failure
3690 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
3694 * Convenience function to free all the side data stored.
3695 * All the other fields stay untouched.
3699 void av_packet_free_side_data(AVPacket *pkt);
3702 * Setup a new reference to the data described by a given packet
3704 * If src is reference-counted, setup dst as a new reference to the
3705 * buffer in src. Otherwise allocate a new buffer in dst and copy the
3706 * data from src into it.
3708 * All the other fields are copied from src.
3710 * @see av_packet_unref
3712 * @param dst Destination packet
3713 * @param src Source packet
3715 * @return 0 on success, a negative AVERROR on error.
3717 int av_packet_ref(AVPacket *dst, const AVPacket *src);
3722 * Unreference the buffer referenced by the packet and reset the
3723 * remaining packet fields to their default values.
3725 * @param pkt The packet to be unreferenced.
3727 void av_packet_unref(AVPacket *pkt);
3730 * Move every field in src to dst and reset src.
3732 * @see av_packet_unref
3734 * @param src Source packet, will be reset
3735 * @param dst Destination packet
3737 void av_packet_move_ref(AVPacket *dst, AVPacket *src);
3740 * Copy only "properties" fields from src to dst.
3742 * Properties for the purpose of this function are all the fields
3743 * beside those related to the packet data (buf, data, size)
3745 * @param dst Destination packet
3746 * @param src Source packet
3748 * @return 0 on success AVERROR on failure.
3751 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
3758 * @addtogroup lavc_decoding
3763 * Find a registered decoder with a matching codec ID.
3765 * @param id AVCodecID of the requested decoder
3766 * @return A decoder if one was found, NULL otherwise.
3768 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3771 * Find a registered decoder with the specified name.
3773 * @param name name of the requested decoder
3774 * @return A decoder if one was found, NULL otherwise.
3776 AVCodec *avcodec_find_decoder_by_name(const char *name);
3778 #if FF_API_GET_BUFFER
3779 attribute_deprecated int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
3780 attribute_deprecated void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
3781 attribute_deprecated int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
3785 * The default callback for AVCodecContext.get_buffer2(). It is made public so
3786 * it can be called by custom get_buffer2() implementations for decoders without
3787 * CODEC_CAP_DR1 set.
3789 int avcodec_default_get_buffer2(AVCodecContext *s, AVFrame *frame, int flags);
3793 * Return the amount of padding in pixels which the get_buffer callback must
3794 * provide around the edge of the image for codecs which do not have the
3795 * CODEC_FLAG_EMU_EDGE flag.
3797 * @return Required padding in pixels.
3799 * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
3802 attribute_deprecated
3803 unsigned avcodec_get_edge_width(void);
3807 * Modify width and height values so that they will result in a memory
3808 * buffer that is acceptable for the codec if you do not use any horizontal
3811 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3813 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3816 * Modify width and height values so that they will result in a memory
3817 * buffer that is acceptable for the codec if you also ensure that all
3818 * line sizes are a multiple of the respective linesize_align[i].
3820 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3822 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3823 int linesize_align[AV_NUM_DATA_POINTERS]);
3826 * Converts AVChromaLocation to swscale x/y chroma position.
3828 * The positions represent the chroma (0,0) position in a coordinates system
3829 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3831 * @param xpos horizontal chroma sample position
3832 * @param ypos vertical chroma sample position
3834 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
3837 * Converts swscale x/y chroma position to AVChromaLocation.
3839 * The positions represent the chroma (0,0) position in a coordinates system
3840 * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3842 * @param xpos horizontal chroma sample position
3843 * @param ypos vertical chroma sample position
3845 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
3847 #if FF_API_OLD_DECODE_AUDIO
3849 * Wrapper function which calls avcodec_decode_audio4.
3851 * @deprecated Use avcodec_decode_audio4 instead.
3853 * Decode the audio frame of size avpkt->size from avpkt->data into samples.
3854 * Some decoders may support multiple frames in a single AVPacket, such
3855 * decoders would then just decode the first frame. In this case,
3856 * avcodec_decode_audio3 has to be called again with an AVPacket that contains
3857 * the remaining data in order to decode the second frame etc.
3859 * could be outputted, frame_size_ptr is zero. Otherwise, it is the
3860 * decompressed frame size in bytes.
3862 * @warning You must set frame_size_ptr to the allocated size of the
3863 * output buffer before calling avcodec_decode_audio3().
3865 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3866 * the actual read bytes because some optimized bitstream readers read 32 or 64
3867 * bits at once and could read over the end.
3869 * @warning The end of the input buffer avpkt->data should be set to 0 to ensure that
3870 * no overreading happens for damaged MPEG streams.
3872 * @warning You must not provide a custom get_buffer() when using
3873 * avcodec_decode_audio3(). Doing so will override it with
3874 * avcodec_default_get_buffer. Use avcodec_decode_audio4() instead,
3875 * which does allow the application to provide a custom get_buffer().
3877 * @note You might have to align the input buffer avpkt->data and output buffer
3878 * samples. The alignment requirements depend on the CPU: On some CPUs it isn't
3879 * necessary at all, on others it won't work at all if not aligned and on others
3880 * it will work but it will have an impact on performance.
3882 * In practice, avpkt->data should have 4 byte alignment at minimum and
3883 * samples should be 16 byte aligned unless the CPU doesn't need it
3884 * (AltiVec and SSE do).
3886 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3887 * between input and output, these need to be fed with avpkt->data=NULL,
3888 * avpkt->size=0 at the end to return the remaining frames.
3890 * @param avctx the codec context
3891 * @param[out] samples the output buffer, sample type in avctx->sample_fmt
3892 * If the sample format is planar, each channel plane will
3893 * be the same size, with no padding between channels.
3894 * @param[in,out] frame_size_ptr the output buffer size in bytes
3895 * @param[in] avpkt The input AVPacket containing the input buffer.
3896 * You can create such packet with av_init_packet() and by then setting
3897 * data and size, some decoders might in addition need other fields.
3898 * All decoders are designed to use the least fields possible though.
3899 * @return On error a negative value is returned, otherwise the number of bytes
3900 * used or zero if no frame data was decompressed (used) from the input AVPacket.
3902 attribute_deprecated int avcodec_decode_audio3(AVCodecContext *avctx, int16_t *samples,
3903 int *frame_size_ptr,
3908 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3910 * Some decoders may support multiple frames in a single AVPacket. Such
3911 * decoders would then just decode the first frame and the return value would be
3912 * less than the packet size. In this case, avcodec_decode_audio4 has to be
3913 * called again with an AVPacket containing the remaining data in order to
3914 * decode the second frame, etc... Even if no frames are returned, the packet
3915 * needs to be fed to the decoder with remaining data until it is completely
3916 * consumed or an error occurs.
3918 * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
3919 * and output. This means that for some packets they will not immediately
3920 * produce decoded output and need to be flushed at the end of decoding to get
3921 * all the decoded data. Flushing is done by calling this function with packets
3922 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
3923 * returning samples. It is safe to flush even those decoders that are not
3924 * marked with CODEC_CAP_DELAY, then no samples will be returned.
3926 * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
3927 * larger than the actual read bytes because some optimized bitstream
3928 * readers read 32 or 64 bits at once and could read over the end.
3930 * @param avctx the codec context
3931 * @param[out] frame The AVFrame in which to store decoded audio samples.
3932 * The decoder will allocate a buffer for the decoded frame by
3933 * calling the AVCodecContext.get_buffer2() callback.
3934 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3935 * reference counted and the returned reference belongs to the
3936 * caller. The caller must release the frame using av_frame_unref()
3937 * when the frame is no longer needed. The caller may safely write
3938 * to the frame if av_frame_is_writable() returns 1.
3939 * When AVCodecContext.refcounted_frames is set to 0, the returned
3940 * reference belongs to the decoder and is valid only until the
3941 * next call to this function or until closing or flushing the
3942 * decoder. The caller may not write to it.
3943 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3944 * non-zero. Note that this field being set to zero
3945 * does not mean that an error has occurred. For
3946 * decoders with CODEC_CAP_DELAY set, no given decode
3947 * call is guaranteed to produce a frame.
3948 * @param[in] avpkt The input AVPacket containing the input buffer.
3949 * At least avpkt->data and avpkt->size should be set. Some
3950 * decoders might also require additional fields to be set.
3951 * @return A negative error code is returned if an error occurred during
3952 * decoding, otherwise the number of bytes consumed from the input
3953 * AVPacket is returned.
3955 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3956 int *got_frame_ptr, const AVPacket *avpkt);
3959 * Decode the video frame of size avpkt->size from avpkt->data into picture.
3960 * Some decoders may support multiple frames in a single AVPacket, such
3961 * decoders would then just decode the first frame.
3963 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3964 * the actual read bytes because some optimized bitstream readers read 32 or 64
3965 * bits at once and could read over the end.
3967 * @warning The end of the input buffer buf should be set to 0 to ensure that
3968 * no overreading happens for damaged MPEG streams.
3970 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3971 * between input and output, these need to be fed with avpkt->data=NULL,
3972 * avpkt->size=0 at the end to return the remaining frames.
3974 * @param avctx the codec context
3975 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3976 * Use av_frame_alloc() to get an AVFrame. The codec will
3977 * allocate memory for the actual bitmap by calling the
3978 * AVCodecContext.get_buffer2() callback.
3979 * When AVCodecContext.refcounted_frames is set to 1, the frame is
3980 * reference counted and the returned reference belongs to the
3981 * caller. The caller must release the frame using av_frame_unref()
3982 * when the frame is no longer needed. The caller may safely write
3983 * to the frame if av_frame_is_writable() returns 1.
3984 * When AVCodecContext.refcounted_frames is set to 0, the returned
3985 * reference belongs to the decoder and is valid only until the
3986 * next call to this function or until closing or flushing the
3987 * decoder. The caller may not write to it.
3989 * @param[in] avpkt The input AVPacket containing the input buffer.
3990 * You can create such packet with av_init_packet() and by then setting
3991 * data and size, some decoders might in addition need other fields like
3992 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3994 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3995 * @return On error a negative value is returned, otherwise the number of bytes
3996 * used or zero if no frame could be decompressed.
3998 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3999 int *got_picture_ptr,
4000 const AVPacket *avpkt);
4003 * Decode a subtitle message.
4004 * Return a negative value on error, otherwise return the number of bytes used.
4005 * If no subtitle could be decompressed, got_sub_ptr is zero.
4006 * Otherwise, the subtitle is stored in *sub.
4007 * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4008 * simplicity, because the performance difference is expect to be negligible
4009 * and reusing a get_buffer written for video codecs would probably perform badly
4010 * due to a potentially very different allocation pattern.
4012 * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
4013 * and output. This means that for some packets they will not immediately
4014 * produce decoded output and need to be flushed at the end of decoding to get
4015 * all the decoded data. Flushing is done by calling this function with packets
4016 * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4017 * returning subtitles. It is safe to flush even those decoders that are not
4018 * marked with CODEC_CAP_DELAY, then no subtitles will be returned.
4020 * @param avctx the codec context
4021 * @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
4022 freed with avsubtitle_free if *got_sub_ptr is set.
4023 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4024 * @param[in] avpkt The input AVPacket containing the input buffer.
4026 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
4031 * @defgroup lavc_parsing Frame parsing
4035 enum AVPictureStructure {
4036 AV_PICTURE_STRUCTURE_UNKNOWN, //< unknown
4037 AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4038 AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4039 AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4042 typedef struct AVCodecParserContext {
4044 struct AVCodecParser *parser;
4045 int64_t frame_offset; /* offset of the current frame */
4046 int64_t cur_offset; /* current offset
4047 (incremented by each av_parser_parse()) */
4048 int64_t next_frame_offset; /* offset of the next frame */
4050 int pict_type; /* XXX: Put it back in AVCodecContext. */
4052 * This field is used for proper frame duration computation in lavf.
4053 * It signals, how much longer the frame duration of the current frame
4054 * is compared to normal frame duration.
4056 * frame_duration = (1 + repeat_pict) * time_base
4058 * It is used by codecs like H.264 to display telecined material.
4060 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4061 int64_t pts; /* pts of the current frame */
4062 int64_t dts; /* dts of the current frame */
4067 int fetch_timestamp;
4069 #define AV_PARSER_PTS_NB 4
4070 int cur_frame_start_index;
4071 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
4072 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
4073 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
4076 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4077 #define PARSER_FLAG_ONCE 0x0002
4078 /// Set if the parser has a valid file offset
4079 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4080 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4082 int64_t offset; ///< byte offset from starting packet start
4083 int64_t cur_frame_end[AV_PARSER_PTS_NB];
4086 * Set by parser to 1 for key frames and 0 for non-key frames.
4087 * It is initialized to -1, so if the parser doesn't set this flag,
4088 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4094 * Time difference in stream time base units from the pts of this
4095 * packet to the point at which the output from the decoder has converged
4096 * independent from the availability of previous frames. That is, the
4097 * frames are virtually identical no matter if decoding started from
4098 * the very first frame or from this keyframe.
4099 * Is AV_NOPTS_VALUE if unknown.
4100 * This field is not the display duration of the current frame.
4101 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
4104 * The purpose of this field is to allow seeking in streams that have no
4105 * keyframes in the conventional sense. It corresponds to the
4106 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
4107 * essential for some types of subtitle streams to ensure that all
4108 * subtitles are correctly displayed after seeking.
4110 int64_t convergence_duration;
4112 // Timestamp generation support:
4114 * Synchronization point for start of timestamp generation.
4116 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4119 * For example, this corresponds to presence of H.264 buffering period
4125 * Offset of the current timestamp against last timestamp sync point in
4126 * units of AVCodecContext.time_base.
4128 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4129 * contain a valid timestamp offset.
4131 * Note that the timestamp of sync point has usually a nonzero
4132 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
4133 * the next frame after timestamp sync point will be usually 1.
4135 * For example, this corresponds to H.264 cpb_removal_delay.
4137 int dts_ref_dts_delta;
4140 * Presentation delay of current frame in units of AVCodecContext.time_base.
4142 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4143 * contain valid non-negative timestamp delta (presentation time of a frame
4144 * must not lie in the past).
4146 * This delay represents the difference between decoding and presentation
4147 * time of the frame.
4149 * For example, this corresponds to H.264 dpb_output_delay.
4154 * Position of the packet in file.
4156 * Analogous to cur_frame_pts/dts
4158 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
4161 * Byte position of currently parsed frame in stream.
4166 * Previous frame byte position.
4171 * Duration of the current frame.
4172 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4173 * For all other types, this is in units of AVCodecContext.time_base.
4177 enum AVFieldOrder field_order;
4180 * Indicate whether a picture is coded as a frame, top field or bottom field.
4182 * For example, H.264 field_pic_flag equal to 0 corresponds to
4183 * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
4184 * equal to 1 and bottom_field_flag equal to 0 corresponds to
4185 * AV_PICTURE_STRUCTURE_TOP_FIELD.
4187 enum AVPictureStructure picture_structure;
4190 * Picture number incremented in presentation or output order.
4191 * This field may be reinitialized at the first picture of a new sequence.
4193 * For example, this corresponds to H.264 PicOrderCnt.
4195 int output_picture_number;
4196 } AVCodecParserContext;
4198 typedef struct AVCodecParser {
4199 int codec_ids[5]; /* several codec IDs are permitted */
4201 int (*parser_init)(AVCodecParserContext *s);
4202 int (*parser_parse)(AVCodecParserContext *s,
4203 AVCodecContext *avctx,
4204 const uint8_t **poutbuf, int *poutbuf_size,
4205 const uint8_t *buf, int buf_size);
4206 void (*parser_close)(AVCodecParserContext *s);
4207 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
4208 struct AVCodecParser *next;
4211 AVCodecParser *av_parser_next(AVCodecParser *c);
4213 void av_register_codec_parser(AVCodecParser *parser);
4214 AVCodecParserContext *av_parser_init(int codec_id);
4219 * @param s parser context.
4220 * @param avctx codec context.
4221 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
4222 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
4223 * @param buf input buffer.
4224 * @param buf_size input length, to signal EOF, this should be 0 (so that the last frame can be output).
4225 * @param pts input presentation timestamp.
4226 * @param dts input decoding timestamp.
4227 * @param pos input byte position in stream.
4228 * @return the number of bytes of the input bitstream used.
4233 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
4240 * decode_frame(data, size);
4244 int av_parser_parse2(AVCodecParserContext *s,
4245 AVCodecContext *avctx,
4246 uint8_t **poutbuf, int *poutbuf_size,
4247 const uint8_t *buf, int buf_size,
4248 int64_t pts, int64_t dts,
4252 * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
4253 * @deprecated use AVBitStreamFilter
4255 int av_parser_change(AVCodecParserContext *s,
4256 AVCodecContext *avctx,
4257 uint8_t **poutbuf, int *poutbuf_size,
4258 const uint8_t *buf, int buf_size, int keyframe);
4259 void av_parser_close(AVCodecParserContext *s);
4267 * @addtogroup lavc_encoding
4272 * Find a registered encoder with a matching codec ID.
4274 * @param id AVCodecID of the requested encoder
4275 * @return An encoder if one was found, NULL otherwise.
4277 AVCodec *avcodec_find_encoder(enum AVCodecID id);
4280 * Find a registered encoder with the specified name.
4282 * @param name name of the requested encoder
4283 * @return An encoder if one was found, NULL otherwise.
4285 AVCodec *avcodec_find_encoder_by_name(const char *name);
4287 #if FF_API_OLD_ENCODE_AUDIO
4289 * Encode an audio frame from samples into buf.
4291 * @deprecated Use avcodec_encode_audio2 instead.
4293 * @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
4294 * However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
4295 * will know how much space is needed because it depends on the value passed
4296 * in buf_size as described below. In that case a lower value can be used.
4298 * @param avctx the codec context
4299 * @param[out] buf the output buffer
4300 * @param[in] buf_size the output buffer size
4301 * @param[in] samples the input buffer containing the samples
4302 * The number of samples read from this buffer is frame_size*channels,
4303 * both of which are defined in avctx.
4304 * For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
4305 * samples read from samples is equal to:
4306 * buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
4307 * This also implies that av_get_bits_per_sample() must not return 0 for these
4309 * @return On error a negative value is returned, on success zero or the number
4310 * of bytes used to encode the data read from the input buffer.
4312 int attribute_deprecated avcodec_encode_audio(AVCodecContext *avctx,
4313 uint8_t *buf, int buf_size,
4314 const short *samples);
4318 * Encode a frame of audio.
4320 * Takes input samples from frame and writes the next output packet, if
4321 * available, to avpkt. The output packet does not necessarily contain data for
4322 * the most recent frame, as encoders can delay, split, and combine input frames
4323 * internally as needed.
4325 * @param avctx codec context
4326 * @param avpkt output AVPacket.
4327 * The user can supply an output buffer by setting
4328 * avpkt->data and avpkt->size prior to calling the
4329 * function, but if the size of the user-provided data is not
4330 * large enough, encoding will fail. If avpkt->data and
4331 * avpkt->size are set, avpkt->destruct must also be set. All
4332 * other AVPacket fields will be reset by the encoder using
4333 * av_init_packet(). If avpkt->data is NULL, the encoder will
4334 * allocate it. The encoder will set avpkt->size to the size
4335 * of the output packet.
4337 * If this function fails or produces no output, avpkt will be
4338 * freed using av_free_packet() (i.e. avpkt->destruct will be
4339 * called to free the user supplied buffer).
4340 * @param[in] frame AVFrame containing the raw audio data to be encoded.
4341 * May be NULL when flushing an encoder that has the
4342 * CODEC_CAP_DELAY capability set.
4343 * If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4344 * can have any number of samples.
4345 * If it is not set, frame->nb_samples must be equal to
4346 * avctx->frame_size for all frames except the last.
4347 * The final frame may be smaller than avctx->frame_size.
4348 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4349 * output packet is non-empty, and to 0 if it is
4350 * empty. If the function returns an error, the
4351 * packet can be assumed to be invalid, and the
4352 * value of got_packet_ptr is undefined and should
4354 * @return 0 on success, negative error code on failure
4356 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
4357 const AVFrame *frame, int *got_packet_ptr);
4359 #if FF_API_OLD_ENCODE_VIDEO
4361 * @deprecated use avcodec_encode_video2() instead.
4363 * Encode a video frame from pict into buf.
4364 * The input picture should be
4365 * stored using a specific format, namely avctx.pix_fmt.
4367 * @param avctx the codec context
4368 * @param[out] buf the output buffer for the bitstream of encoded frame
4369 * @param[in] buf_size the size of the output buffer in bytes
4370 * @param[in] pict the input picture to encode
4371 * @return On error a negative value is returned, on success zero or the number
4372 * of bytes used from the output buffer.
4374 attribute_deprecated
4375 int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4376 const AVFrame *pict);
4380 * Encode a frame of video.
4382 * Takes input raw video data from frame and writes the next output packet, if
4383 * available, to avpkt. The output packet does not necessarily contain data for
4384 * the most recent frame, as encoders can delay and reorder input frames
4385 * internally as needed.
4387 * @param avctx codec context
4388 * @param avpkt output AVPacket.
4389 * The user can supply an output buffer by setting
4390 * avpkt->data and avpkt->size prior to calling the
4391 * function, but if the size of the user-provided data is not
4392 * large enough, encoding will fail. All other AVPacket fields
4393 * will be reset by the encoder using av_init_packet(). If
4394 * avpkt->data is NULL, the encoder will allocate it.
4395 * The encoder will set avpkt->size to the size of the
4396 * output packet. The returned data (if any) belongs to the
4397 * caller, he is responsible for freeing it.
4399 * If this function fails or produces no output, avpkt will be
4400 * freed using av_free_packet() (i.e. avpkt->destruct will be
4401 * called to free the user supplied buffer).
4402 * @param[in] frame AVFrame containing the raw video data to be encoded.
4403 * May be NULL when flushing an encoder that has the
4404 * CODEC_CAP_DELAY capability set.
4405 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4406 * output packet is non-empty, and to 0 if it is
4407 * empty. If the function returns an error, the
4408 * packet can be assumed to be invalid, and the
4409 * value of got_packet_ptr is undefined and should
4411 * @return 0 on success, negative error code on failure
4413 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
4414 const AVFrame *frame, int *got_packet_ptr);
4416 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4417 const AVSubtitle *sub);
4424 #if FF_API_AVCODEC_RESAMPLE
4426 * @defgroup lavc_resample Audio resampling
4428 * @deprecated use libswresample instead
4432 struct ReSampleContext;
4433 struct AVResampleContext;
4435 typedef struct ReSampleContext ReSampleContext;
4438 * Initialize audio resampling context.
4440 * @param output_channels number of output channels
4441 * @param input_channels number of input channels
4442 * @param output_rate output sample rate
4443 * @param input_rate input sample rate
4444 * @param sample_fmt_out requested output sample format
4445 * @param sample_fmt_in input sample format
4446 * @param filter_length length of each FIR filter in the filterbank relative to the cutoff frequency
4447 * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4448 * @param linear if 1 then the used FIR filter will be linearly interpolated
4449 between the 2 closest, if 0 the closest will be used
4450 * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4451 * @return allocated ReSampleContext, NULL if error occurred
4453 attribute_deprecated
4454 ReSampleContext *av_audio_resample_init(int output_channels, int input_channels,
4455 int output_rate, int input_rate,
4456 enum AVSampleFormat sample_fmt_out,
4457 enum AVSampleFormat sample_fmt_in,
4458 int filter_length, int log2_phase_count,
4459 int linear, double cutoff);
4461 attribute_deprecated
4462 int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
4465 * Free resample context.
4467 * @param s a non-NULL pointer to a resample context previously
4468 * created with av_audio_resample_init()
4470 attribute_deprecated
4471 void audio_resample_close(ReSampleContext *s);
4475 * Initialize an audio resampler.
4476 * Note, if either rate is not an integer then simply scale both rates up so they are.
4477 * @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
4478 * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4479 * @param linear If 1 then the used FIR filter will be linearly interpolated
4480 between the 2 closest, if 0 the closest will be used
4481 * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4483 attribute_deprecated
4484 struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff);
4487 * Resample an array of samples using a previously configured context.
4488 * @param src an array of unconsumed samples
4489 * @param consumed the number of samples of src which have been consumed are returned here
4490 * @param src_size the number of unconsumed samples available
4491 * @param dst_size the amount of space in samples available in dst
4492 * @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.
4493 * @return the number of samples written in dst or -1 if an error occurred
4495 attribute_deprecated
4496 int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx);
4500 * Compensate samplerate/timestamp drift. The compensation is done by changing
4501 * the resampler parameters, so no audible clicks or similar distortions occur
4502 * @param compensation_distance distance in output samples over which the compensation should be performed
4503 * @param sample_delta number of output samples which should be output less
4505 * example: av_resample_compensate(c, 10, 500)
4506 * here instead of 510 samples only 500 samples would be output
4508 * note, due to rounding the actual compensation might be slightly different,
4509 * especially if the compensation_distance is large and the in_rate used during init is small
4511 attribute_deprecated
4512 void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance);
4513 attribute_deprecated
4514 void av_resample_close(struct AVResampleContext *c);
4522 * @addtogroup lavc_picture
4527 * Allocate memory for the pixels of a picture and setup the AVPicture
4530 * Call avpicture_free() to free it.
4532 * @param picture the picture structure to be filled in
4533 * @param pix_fmt the pixel format of the picture
4534 * @param width the width of the picture
4535 * @param height the height of the picture
4536 * @return zero if successful, a negative error code otherwise
4538 * @see av_image_alloc(), avpicture_fill()
4540 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
4543 * Free a picture previously allocated by avpicture_alloc().
4544 * The data buffer used by the AVPicture is freed, but the AVPicture structure
4547 * @param picture the AVPicture to be freed
4549 void avpicture_free(AVPicture *picture);
4552 * Setup the picture fields based on the specified image parameters
4553 * and the provided image data buffer.
4555 * The picture fields are filled in by using the image data buffer
4556 * pointed to by ptr.
4558 * If ptr is NULL, the function will fill only the picture linesize
4559 * array and return the required size for the image buffer.
4561 * To allocate an image buffer and fill the picture data in one call,
4562 * use avpicture_alloc().
4564 * @param picture the picture to be filled in
4565 * @param ptr buffer where the image data is stored, or NULL
4566 * @param pix_fmt the pixel format of the image
4567 * @param width the width of the image in pixels
4568 * @param height the height of the image in pixels
4569 * @return the size in bytes required for src, a negative error code
4570 * in case of failure
4572 * @see av_image_fill_arrays()
4574 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
4575 enum AVPixelFormat pix_fmt, int width, int height);
4578 * Copy pixel data from an AVPicture into a buffer.
4580 * avpicture_get_size() can be used to compute the required size for
4581 * the buffer to fill.
4583 * @param src source picture with filled data
4584 * @param pix_fmt picture pixel format
4585 * @param width picture width
4586 * @param height picture height
4587 * @param dest destination buffer
4588 * @param dest_size destination buffer size in bytes
4589 * @return the number of bytes written to dest, or a negative value
4590 * (error code) on error, for example if the destination buffer is not
4593 * @see av_image_copy_to_buffer()
4595 int avpicture_layout(const AVPicture *src, enum AVPixelFormat pix_fmt,
4596 int width, int height,
4597 unsigned char *dest, int dest_size);
4600 * Calculate the size in bytes that a picture of the given width and height
4601 * would occupy if stored in the given picture format.
4603 * @param pix_fmt picture pixel format
4604 * @param width picture width
4605 * @param height picture height
4606 * @return the computed picture buffer size or a negative error code
4609 * @see av_image_get_buffer_size().
4611 int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height);
4613 #if FF_API_DEINTERLACE
4615 * deinterlace - if not supported return -1
4617 * @deprecated - use yadif (in libavfilter) instead
4619 attribute_deprecated
4620 int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
4621 enum AVPixelFormat pix_fmt, int width, int height);
4624 * Copy image src to dst. Wraps av_image_copy().
4626 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4627 enum AVPixelFormat pix_fmt, int width, int height);
4630 * Crop image top and left side.
4632 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4633 enum AVPixelFormat pix_fmt, int top_band, int left_band);
4638 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
4639 int padtop, int padbottom, int padleft, int padright, int *color);
4646 * @defgroup lavc_misc Utility functions
4649 * Miscellaneous utility functions related to both encoding and decoding
4655 * @defgroup lavc_misc_pixfmt Pixel formats
4657 * Functions for working with pixel formats.
4662 * Utility function to access log2_chroma_w log2_chroma_h from
4663 * the pixel format AVPixFmtDescriptor.
4665 * This function asserts that pix_fmt is valid. See av_pix_fmt_get_chroma_sub_sample
4666 * for one that returns a failure code and continues in case of invalid
4669 * @param[in] pix_fmt the pixel format
4670 * @param[out] h_shift store log2_chroma_w
4671 * @param[out] v_shift store log2_chroma_h
4673 * @see av_pix_fmt_get_chroma_sub_sample
4676 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
4679 * Return a value representing the fourCC code associated to the
4680 * pixel format pix_fmt, or 0 if no associated fourCC code can be
4683 unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt);
4685 #define FF_LOSS_RESOLUTION 0x0001 /**< loss due to resolution change */
4686 #define FF_LOSS_DEPTH 0x0002 /**< loss due to color depth change */
4687 #define FF_LOSS_COLORSPACE 0x0004 /**< loss due to color space conversion */
4688 #define FF_LOSS_ALPHA 0x0008 /**< loss of alpha bits */
4689 #define FF_LOSS_COLORQUANT 0x0010 /**< loss due to color quantization */
4690 #define FF_LOSS_CHROMA 0x0020 /**< loss of chroma (e.g. RGB to gray conversion) */
4693 * Compute what kind of losses will occur when converting from one specific
4694 * pixel format to another.
4695 * When converting from one pixel format to another, information loss may occur.
4696 * For example, when converting from RGB24 to GRAY, the color information will
4697 * be lost. Similarly, other losses occur when converting from some formats to
4698 * other formats. These losses can involve loss of chroma, but also loss of
4699 * resolution, loss of color depth, loss due to the color space conversion, loss
4700 * of the alpha bits or loss due to color quantization.
4701 * avcodec_get_fix_fmt_loss() informs you about the various types of losses
4702 * which will occur when converting from one pixel format to another.
4704 * @param[in] dst_pix_fmt destination pixel format
4705 * @param[in] src_pix_fmt source pixel format
4706 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4707 * @return Combination of flags informing you what kind of losses will occur
4708 * (maximum loss for an invalid dst_pix_fmt).
4710 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
4714 * Find the best pixel format to convert to given a certain source pixel
4715 * format. When converting from one pixel format to another, information loss
4716 * may occur. For example, when converting from RGB24 to GRAY, the color
4717 * information will be lost. Similarly, other losses occur when converting from
4718 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
4719 * the given pixel formats should be used to suffer the least amount of loss.
4720 * The pixel formats from which it chooses one, are determined by the
4721 * pix_fmt_list parameter.
4724 * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
4725 * @param[in] src_pix_fmt source pixel format
4726 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4727 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4728 * @return The best pixel format to convert to or -1 if none was found.
4730 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
4731 enum AVPixelFormat src_pix_fmt,
4732 int has_alpha, int *loss_ptr);
4735 * Find the best pixel format to convert to given a certain source pixel
4736 * format and a selection of two destination pixel formats. When converting from
4737 * one pixel format to another, information loss may occur. For example, when converting
4738 * from RGB24 to GRAY, the color information will be lost. Similarly, other losses occur when
4739 * converting from some formats to other formats. avcodec_find_best_pix_fmt_of_2() selects which of
4740 * the given pixel formats should be used to suffer the least amount of loss.
4742 * If one of the destination formats is AV_PIX_FMT_NONE the other pixel format (if valid) will be
4746 * src_pix_fmt = AV_PIX_FMT_YUV420P;
4747 * dst_pix_fmt1= AV_PIX_FMT_RGB24;
4748 * dst_pix_fmt2= AV_PIX_FMT_GRAY8;
4749 * dst_pix_fmt3= AV_PIX_FMT_RGB8;
4750 * loss= FF_LOSS_CHROMA; // don't care about chroma loss, so chroma loss will be ignored.
4751 * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt1, dst_pix_fmt2, src_pix_fmt, alpha, &loss);
4752 * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt, dst_pix_fmt3, src_pix_fmt, alpha, &loss);
4755 * @param[in] dst_pix_fmt1 One of the two destination pixel formats to choose from
4756 * @param[in] dst_pix_fmt2 The other of the two destination pixel formats to choose from
4757 * @param[in] src_pix_fmt Source pixel format
4758 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4759 * @param[in, out] loss_ptr Combination of loss flags. In: selects which of the losses to ignore, i.e.
4760 * NULL or value of zero means we care about all losses. Out: the loss
4761 * that occurs when converting from src to selected dst pixel format.
4762 * @return The best pixel format to convert to or -1 if none was found.
4764 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4765 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4767 attribute_deprecated
4768 #if AV_HAVE_INCOMPATIBLE_LIBAV_ABI
4769 enum AVPixelFormat avcodec_find_best_pix_fmt2(const enum AVPixelFormat *pix_fmt_list,
4770 enum AVPixelFormat src_pix_fmt,
4771 int has_alpha, int *loss_ptr);
4773 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4774 enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4778 enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
4784 #if FF_API_SET_DIMENSIONS
4786 * @deprecated this function is not supposed to be used from outside of lavc
4788 attribute_deprecated
4789 void avcodec_set_dimensions(AVCodecContext *s, int width, int height);
4793 * Put a string representing the codec tag codec_tag in buf.
4795 * @param buf buffer to place codec tag in
4796 * @param buf_size size in bytes of buf
4797 * @param codec_tag codec tag to assign
4798 * @return the length of the string that would have been generated if
4799 * enough space had been available, excluding the trailing null
4801 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
4803 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
4806 * Return a name for the specified profile, if available.
4808 * @param codec the codec that is searched for the given profile
4809 * @param profile the profile value for which a name is requested
4810 * @return A name for the profile if found, NULL otherwise.
4812 const char *av_get_profile_name(const AVCodec *codec, int profile);
4814 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
4815 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
4816 //FIXME func typedef
4819 * Fill AVFrame audio data and linesize pointers.
4821 * The buffer buf must be a preallocated buffer with a size big enough
4822 * to contain the specified samples amount. The filled AVFrame data
4823 * pointers will point to this buffer.
4825 * AVFrame extended_data channel pointers are allocated if necessary for
4828 * @param frame the AVFrame
4829 * frame->nb_samples must be set prior to calling the
4830 * function. This function fills in frame->data,
4831 * frame->extended_data, frame->linesize[0].
4832 * @param nb_channels channel count
4833 * @param sample_fmt sample format
4834 * @param buf buffer to use for frame data
4835 * @param buf_size size of buffer
4836 * @param align plane size sample alignment (0 = default)
4837 * @return >=0 on success, negative error code on failure
4838 * @todo return the size in bytes required to store the samples in
4839 * case of success, at the next libavutil bump
4841 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
4842 enum AVSampleFormat sample_fmt, const uint8_t *buf,
4843 int buf_size, int align);
4846 * Reset the internal decoder state / flush internal buffers. Should be called
4847 * e.g. when seeking or when switching to a different stream.
4849 * @note when refcounted frames are not used (i.e. avctx->refcounted_frames is 0),
4850 * this invalidates the frames previously returned from the decoder. When
4851 * refcounted frames are used, the decoder just releases any references it might
4852 * keep internally, but the caller's reference remains valid.
4854 void avcodec_flush_buffers(AVCodecContext *avctx);
4857 * Return codec bits per sample.
4859 * @param[in] codec_id the codec
4860 * @return Number of bits per sample or zero if unknown for the given codec.
4862 int av_get_bits_per_sample(enum AVCodecID codec_id);
4865 * Return the PCM codec associated with a sample format.
4866 * @param be endianness, 0 for little, 1 for big,
4867 * -1 (or anything else) for native
4868 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
4870 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
4873 * Return codec bits per sample.
4874 * Only return non-zero if the bits per sample is exactly correct, not an
4877 * @param[in] codec_id the codec
4878 * @return Number of bits per sample or zero if unknown for the given codec.
4880 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
4883 * Return audio frame duration.
4885 * @param avctx codec context
4886 * @param frame_bytes size of the frame, or 0 if unknown
4887 * @return frame duration, in samples, if known. 0 if not able to
4890 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4893 typedef struct AVBitStreamFilterContext {
4895 struct AVBitStreamFilter *filter;
4896 AVCodecParserContext *parser;
4897 struct AVBitStreamFilterContext *next;
4898 } AVBitStreamFilterContext;
4901 typedef struct AVBitStreamFilter {
4904 int (*filter)(AVBitStreamFilterContext *bsfc,
4905 AVCodecContext *avctx, const char *args,
4906 uint8_t **poutbuf, int *poutbuf_size,
4907 const uint8_t *buf, int buf_size, int keyframe);
4908 void (*close)(AVBitStreamFilterContext *bsfc);
4909 struct AVBitStreamFilter *next;
4910 } AVBitStreamFilter;
4913 * Register a bitstream filter.
4915 * The filter will be accessible to the application code through
4916 * av_bitstream_filter_next() or can be directly initialized with
4917 * av_bitstream_filter_init().
4919 * @see avcodec_register_all()
4921 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4924 * Create and initialize a bitstream filter context given a bitstream
4927 * The returned context must be freed with av_bitstream_filter_close().
4929 * @param name the name of the bitstream filter
4930 * @return a bitstream filter context if a matching filter was found
4931 * and successfully initialized, NULL otherwise
4933 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4938 * This function filters the buffer buf with size buf_size, and places the
4939 * filtered buffer in the buffer pointed to by poutbuf.
4941 * The output buffer must be freed by the caller.
4943 * @param bsfc bitstream filter context created by av_bitstream_filter_init()
4944 * @param avctx AVCodecContext accessed by the filter, may be NULL.
4945 * If specified, this must point to the encoder context of the
4946 * output stream the packet is sent to.
4947 * @param args arguments which specify the filter configuration, may be NULL
4948 * @param poutbuf pointer which is updated to point to the filtered buffer
4949 * @param poutbuf_size pointer which is updated to the filtered buffer size in bytes
4950 * @param buf buffer containing the data to filter
4951 * @param buf_size size in bytes of buf
4952 * @param keyframe set to non-zero if the buffer to filter corresponds to a key-frame packet data
4953 * @return >= 0 in case of success, or a negative error code in case of failure
4955 * If the return value is positive, an output buffer is allocated and
4956 * is availble in *poutbuf, and is distinct from the input buffer.
4958 * If the return value is 0, the output buffer is not allocated and
4959 * should be considered identical to the input buffer, or in case
4960 * *poutbuf was set it points to the input buffer (not necessarily to
4961 * its starting address).
4963 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4964 AVCodecContext *avctx, const char *args,
4965 uint8_t **poutbuf, int *poutbuf_size,
4966 const uint8_t *buf, int buf_size, int keyframe);
4969 * Release bitstream filter context.
4971 * @param bsf the bitstream filter context created with
4972 * av_bitstream_filter_init(), can be NULL
4974 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4977 * If f is NULL, return the first registered bitstream filter,
4978 * if f is non-NULL, return the next registered bitstream filter
4979 * after f, or NULL if f is the last one.
4981 * This function can be used to iterate over all registered bitstream
4984 AVBitStreamFilter *av_bitstream_filter_next(AVBitStreamFilter *f);
4989 * Same behaviour av_fast_malloc but the buffer has additional
4990 * FF_INPUT_BUFFER_PADDING_SIZE at the end which will always be 0.
4992 * In addition the whole buffer will initially and after resizes
4993 * be 0-initialized so that no uninitialized data will ever appear.
4995 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4998 * Same behaviour av_fast_padded_malloc except that buffer will always
4999 * be 0-initialized after call.
5001 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
5004 * Encode extradata length to a buffer. Used by xiph codecs.
5006 * @param s buffer to write to; must be at least (v/255+1) bytes long
5007 * @param v size of extradata in bytes
5008 * @return number of bytes written to the buffer.
5010 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
5012 #if FF_API_MISSING_SAMPLE
5014 * Log a generic warning message about a missing feature. This function is
5015 * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
5016 * only, and would normally not be used by applications.
5017 * @param[in] avc a pointer to an arbitrary struct of which the first field is
5018 * a pointer to an AVClass struct
5019 * @param[in] feature string containing the name of the missing feature
5020 * @param[in] want_sample indicates if samples are wanted which exhibit this feature.
5021 * If want_sample is non-zero, additional verbage will be added to the log
5022 * message which tells the user how to report samples to the development
5024 * @deprecated Use avpriv_report_missing_feature() instead.
5026 attribute_deprecated
5027 void av_log_missing_feature(void *avc, const char *feature, int want_sample);
5030 * Log a generic warning message asking for a sample. This function is
5031 * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
5032 * only, and would normally not be used by applications.
5033 * @param[in] avc a pointer to an arbitrary struct of which the first field is
5034 * a pointer to an AVClass struct
5035 * @param[in] msg string containing an optional message, or NULL if no message
5036 * @deprecated Use avpriv_request_sample() instead.
5038 attribute_deprecated
5039 void av_log_ask_for_sample(void *avc, const char *msg, ...) av_printf_format(2, 3);
5040 #endif /* FF_API_MISSING_SAMPLE */
5043 * Register the hardware accelerator hwaccel.
5045 void av_register_hwaccel(AVHWAccel *hwaccel);
5048 * If hwaccel is NULL, returns the first registered hardware accelerator,
5049 * if hwaccel is non-NULL, returns the next registered hardware accelerator
5050 * after hwaccel, or NULL if hwaccel is the last one.
5052 AVHWAccel *av_hwaccel_next(AVHWAccel *hwaccel);
5056 * Lock operation used by lockmgr
5059 AV_LOCK_CREATE, ///< Create a mutex
5060 AV_LOCK_OBTAIN, ///< Lock the mutex
5061 AV_LOCK_RELEASE, ///< Unlock the mutex
5062 AV_LOCK_DESTROY, ///< Free mutex resources
5066 * Register a user provided lock manager supporting the operations
5067 * specified by AVLockOp. mutex points to a (void *) where the
5068 * lockmgr should store/get a pointer to a user allocated mutex. It's
5069 * NULL upon AV_LOCK_CREATE and != NULL for all other ops.
5071 * @param cb User defined callback. Note: FFmpeg may invoke calls to this
5072 * callback during the call to av_lockmgr_register().
5073 * Thus, the application must be prepared to handle that.
5074 * If cb is set to NULL the lockmgr will be unregistered.
5075 * Also note that during unregistration the previously registered
5076 * lockmgr callback may also be invoked.
5078 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
5081 * Get the type of the given codec.
5083 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
5086 * Get the name of a codec.
5087 * @return a static string identifying the codec; never NULL
5089 const char *avcodec_get_name(enum AVCodecID id);
5092 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
5093 * with no corresponding avcodec_close()), 0 otherwise.
5095 int avcodec_is_open(AVCodecContext *s);
5098 * @return a non-zero number if codec is an encoder, zero otherwise
5100 int av_codec_is_encoder(const AVCodec *codec);
5103 * @return a non-zero number if codec is a decoder, zero otherwise
5105 int av_codec_is_decoder(const AVCodec *codec);
5108 * @return descriptor for given codec ID or NULL if no descriptor exists.
5110 const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
5113 * Iterate over all codec descriptors known to libavcodec.
5115 * @param prev previous descriptor. NULL to get the first descriptor.
5117 * @return next descriptor or NULL after the last descriptor
5119 const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
5122 * @return codec descriptor with the given name or NULL if no such descriptor
5125 const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
5131 #endif /* AVCODEC_AVCODEC_H */