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
30 #include "libavutil/samplefmt.h"
31 #include "libavutil/avutil.h"
32 #include "libavutil/cpu.h"
33 #include "libavutil/dict.h"
34 #include "libavutil/log.h"
35 #include "libavutil/pixfmt.h"
36 #include "libavutil/rational.h"
37 #include "libavutil/audioconvert.h"
39 #include "libavcodec/version.h"
41 * @defgroup libavc Encoding/Decoding Library
44 * @defgroup lavc_decoding Decoding
48 * @defgroup lavc_encoding Encoding
52 * @defgroup lavc_codec Codecs
54 * @defgroup lavc_codec_native Native Codecs
57 * @defgroup lavc_codec_wrappers External library wrappers
60 * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
64 * @defgroup lavc_internal Internal
72 * @defgroup lavc_core Core functions/structures.
75 * Basic definitions, functions for querying libavcodec capabilities,
76 * allocating core structures, etc.
82 * Identify the syntax and semantics of the bitstream.
83 * The principle is roughly:
84 * Two decoders with the same ID can decode the same streams.
85 * Two encoders with the same ID can encode compatible streams.
86 * There may be slight deviations from the principle due to implementation
89 * If you add a codec ID to this list, add it so that
90 * 1. no value of a existing codec ID changes (that would break ABI),
91 * 2. Give it a value which when taken as ASCII is recognized uniquely by a human as this specific codec.
92 * This ensures that 2 forks can independently add AVCodecIDs without producing conflicts.
94 * After adding new codec IDs, do not forget to add an entry to the codec
95 * descriptor list and bump libavcodec minor version.
101 AV_CODEC_ID_MPEG1VIDEO,
102 AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
103 AV_CODEC_ID_MPEG2VIDEO_XVMC,
114 AV_CODEC_ID_RAWVIDEO,
115 AV_CODEC_ID_MSMPEG4V1,
116 AV_CODEC_ID_MSMPEG4V2,
117 AV_CODEC_ID_MSMPEG4V3,
140 AV_CODEC_ID_INTERPLAY_VIDEO,
147 AV_CODEC_ID_MSVIDEO1,
152 AV_CODEC_ID_TRUEMOTION1,
153 AV_CODEC_ID_VMDVIDEO,
179 AV_CODEC_ID_TRUEMOTION2,
185 AV_CODEC_ID_SMACKVIDEO,
190 AV_CODEC_ID_JPEG2000,
196 AV_CODEC_ID_DSICINVIDEO,
197 AV_CODEC_ID_TIERTEXSEQVIDEO,
205 AV_CODEC_ID_BETHSOFTVID,
217 AV_CODEC_ID_ESCAPE124,
221 AV_CODEC_ID_MOTIONPIXELS,
233 AV_CODEC_ID_FLASHSV2,
234 AV_CODEC_ID_CDGRAPHICS,
237 AV_CODEC_ID_BINKVIDEO,
238 AV_CODEC_ID_IFF_ILBM,
239 AV_CODEC_ID_IFF_BYTERUN1,
245 AV_CODEC_ID_A64_MULTI,
246 AV_CODEC_ID_A64_MULTI5,
249 AV_CODEC_ID_LAGARITH,
253 AV_CODEC_ID_WMV3IMAGE,
254 AV_CODEC_ID_VC1IMAGE,
256 AV_CODEC_ID_BMV_VIDEO,
263 AV_CODEC_ID_ZEROCODEC,
270 AV_CODEC_ID_Y41P = MKBETAG('Y','4','1','P'),
271 AV_CODEC_ID_ESCAPE130 = MKBETAG('E','1','3','0'),
272 AV_CODEC_ID_EXR = MKBETAG('0','E','X','R'),
273 AV_CODEC_ID_AVRP = MKBETAG('A','V','R','P'),
275 AV_CODEC_ID_G2M = MKBETAG( 0 ,'G','2','M'),
276 AV_CODEC_ID_AVUI = MKBETAG('A','V','U','I'),
277 AV_CODEC_ID_AYUV = MKBETAG('A','Y','U','V'),
278 AV_CODEC_ID_V308 = MKBETAG('V','3','0','8'),
279 AV_CODEC_ID_V408 = MKBETAG('V','4','0','8'),
280 AV_CODEC_ID_YUV4 = MKBETAG('Y','U','V','4'),
281 AV_CODEC_ID_SANM = MKBETAG('S','A','N','M'),
282 AV_CODEC_ID_PAF_VIDEO = MKBETAG('P','A','F','V'),
283 AV_CODEC_ID_AVRN = MKBETAG('A','V','R','n'),
284 AV_CODEC_ID_CPIA = MKBETAG('C','P','I','A'),
286 /* various PCM "codecs" */
287 AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
288 AV_CODEC_ID_PCM_S16LE = 0x10000,
289 AV_CODEC_ID_PCM_S16BE,
290 AV_CODEC_ID_PCM_U16LE,
291 AV_CODEC_ID_PCM_U16BE,
294 AV_CODEC_ID_PCM_MULAW,
295 AV_CODEC_ID_PCM_ALAW,
296 AV_CODEC_ID_PCM_S32LE,
297 AV_CODEC_ID_PCM_S32BE,
298 AV_CODEC_ID_PCM_U32LE,
299 AV_CODEC_ID_PCM_U32BE,
300 AV_CODEC_ID_PCM_S24LE,
301 AV_CODEC_ID_PCM_S24BE,
302 AV_CODEC_ID_PCM_U24LE,
303 AV_CODEC_ID_PCM_U24BE,
304 AV_CODEC_ID_PCM_S24DAUD,
305 AV_CODEC_ID_PCM_ZORK,
306 AV_CODEC_ID_PCM_S16LE_PLANAR,
308 AV_CODEC_ID_PCM_F32BE,
309 AV_CODEC_ID_PCM_F32LE,
310 AV_CODEC_ID_PCM_F64BE,
311 AV_CODEC_ID_PCM_F64LE,
312 AV_CODEC_ID_PCM_BLURAY,
315 AV_CODEC_ID_PCM_S8_PLANAR,
317 /* various ADPCM codecs */
318 AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
319 AV_CODEC_ID_ADPCM_IMA_WAV,
320 AV_CODEC_ID_ADPCM_IMA_DK3,
321 AV_CODEC_ID_ADPCM_IMA_DK4,
322 AV_CODEC_ID_ADPCM_IMA_WS,
323 AV_CODEC_ID_ADPCM_IMA_SMJPEG,
324 AV_CODEC_ID_ADPCM_MS,
325 AV_CODEC_ID_ADPCM_4XM,
326 AV_CODEC_ID_ADPCM_XA,
327 AV_CODEC_ID_ADPCM_ADX,
328 AV_CODEC_ID_ADPCM_EA,
329 AV_CODEC_ID_ADPCM_G726,
330 AV_CODEC_ID_ADPCM_CT,
331 AV_CODEC_ID_ADPCM_SWF,
332 AV_CODEC_ID_ADPCM_YAMAHA,
333 AV_CODEC_ID_ADPCM_SBPRO_4,
334 AV_CODEC_ID_ADPCM_SBPRO_3,
335 AV_CODEC_ID_ADPCM_SBPRO_2,
336 AV_CODEC_ID_ADPCM_THP,
337 AV_CODEC_ID_ADPCM_IMA_AMV,
338 AV_CODEC_ID_ADPCM_EA_R1,
339 AV_CODEC_ID_ADPCM_EA_R3,
340 AV_CODEC_ID_ADPCM_EA_R2,
341 AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
342 AV_CODEC_ID_ADPCM_IMA_EA_EACS,
343 AV_CODEC_ID_ADPCM_EA_XAS,
344 AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
345 AV_CODEC_ID_ADPCM_IMA_ISS,
346 AV_CODEC_ID_ADPCM_G722,
347 AV_CODEC_ID_ADPCM_IMA_APC,
348 AV_CODEC_ID_VIMA = MKBETAG('V','I','M','A'),
351 AV_CODEC_ID_AMR_NB = 0x12000,
354 /* RealAudio codecs*/
355 AV_CODEC_ID_RA_144 = 0x13000,
358 /* various DPCM codecs */
359 AV_CODEC_ID_ROQ_DPCM = 0x14000,
360 AV_CODEC_ID_INTERPLAY_DPCM,
361 AV_CODEC_ID_XAN_DPCM,
362 AV_CODEC_ID_SOL_DPCM,
365 AV_CODEC_ID_MP2 = 0x15000,
366 AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
376 AV_CODEC_ID_VMDAUDIO,
382 AV_CODEC_ID_WESTWOOD_SND1,
383 AV_CODEC_ID_GSM, ///< as in Berlin toast format
386 AV_CODEC_ID_TRUESPEECH,
388 AV_CODEC_ID_SMACKAUDIO,
391 AV_CODEC_ID_DSICINAUDIO,
393 AV_CODEC_ID_MUSEPACK7,
395 AV_CODEC_ID_GSM_MS, /* as found in WAV */
399 AV_CODEC_ID_NELLYMOSER,
400 AV_CODEC_ID_MUSEPACK8,
402 AV_CODEC_ID_WMAVOICE,
404 AV_CODEC_ID_WMALOSSLESS,
413 AV_CODEC_ID_BINKAUDIO_RDFT,
414 AV_CODEC_ID_BINKAUDIO_DCT,
415 AV_CODEC_ID_AAC_LATM,
420 AV_CODEC_ID_8SVX_EXP,
421 AV_CODEC_ID_8SVX_FIB,
422 AV_CODEC_ID_BMV_AUDIO,
426 AV_CODEC_ID_OPUS_DEPRECATED,
427 AV_CODEC_ID_FFWAVESYNTH = MKBETAG('F','F','W','S'),
428 AV_CODEC_ID_8SVX_RAW = MKBETAG('8','S','V','X'),
429 AV_CODEC_ID_SONIC = MKBETAG('S','O','N','C'),
430 AV_CODEC_ID_SONIC_LS = MKBETAG('S','O','N','L'),
431 AV_CODEC_ID_PAF_AUDIO = MKBETAG('P','A','F','A'),
432 AV_CODEC_ID_OPUS = MKBETAG('O','P','U','S'),
434 /* subtitle codecs */
435 AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
436 AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
437 AV_CODEC_ID_DVB_SUBTITLE,
438 AV_CODEC_ID_TEXT, ///< raw UTF-8 text
441 AV_CODEC_ID_MOV_TEXT,
442 AV_CODEC_ID_HDMV_PGS_SUBTITLE,
443 AV_CODEC_ID_DVB_TELETEXT,
445 AV_CODEC_ID_MICRODVD = MKBETAG('m','D','V','D'),
446 AV_CODEC_ID_EIA_608 = MKBETAG('c','6','0','8'),
447 AV_CODEC_ID_JACOSUB = MKBETAG('J','S','U','B'),
448 AV_CODEC_ID_SAMI = MKBETAG('S','A','M','I'),
449 AV_CODEC_ID_REALTEXT = MKBETAG('R','T','X','T'),
450 AV_CODEC_ID_SUBVIEWER = MKBETAG('S','u','b','V'),
451 AV_CODEC_ID_SUBRIP = MKBETAG('S','R','i','p'),
452 AV_CODEC_ID_WEBVTT = MKBETAG('W','V','T','T'),
454 /* other specific kind of codecs (generally used for attachments) */
455 AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
456 AV_CODEC_ID_TTF = 0x18000,
457 AV_CODEC_ID_BINTEXT = MKBETAG('B','T','X','T'),
458 AV_CODEC_ID_XBIN = MKBETAG('X','B','I','N'),
459 AV_CODEC_ID_IDF = MKBETAG( 0 ,'I','D','F'),
460 AV_CODEC_ID_OTF = MKBETAG( 0 ,'O','T','F'),
462 AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
464 AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
465 * stream (only used by libavformat) */
466 AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
467 * stream (only used by libavformat) */
468 AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
471 #include "old_codec_ids.h"
476 #define CodecID AVCodecID
480 * This struct describes the properties of a single codec described by an
482 * @see avcodec_get_descriptor()
484 typedef struct AVCodecDescriptor {
486 enum AVMediaType type;
488 * Name of the codec described by this descriptor. It is non-empty and
489 * unique for each codec descriptor. It should contain alphanumeric
490 * characters and '_' only.
494 * A more descriptive name for this codec. May be NULL.
496 const char *long_name;
498 * Codec properties, a combination of AV_CODEC_PROP_* flags.
504 * Codec uses only intra compression.
507 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
509 * Codec supports lossy compression. Audio and video codecs only.
510 * @note a codec may support both lossy and lossless
513 #define AV_CODEC_PROP_LOSSY (1 << 1)
515 * Codec supports lossless compression. Audio and video codecs only.
517 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
519 #if FF_API_OLD_DECODE_AUDIO
521 #define AVCODEC_MAX_AUDIO_FRAME_SIZE 192000 // 1 second of 48khz 32bit audio
525 * @ingroup lavc_decoding
526 * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
527 * This is mainly needed because some optimized bitstream readers read
528 * 32 or 64 bit at once and could read over the end.<br>
529 * Note: If the first 23 bits of the additional bytes are not 0, then damaged
530 * MPEG bitstreams could cause overread and segfault.
532 #define FF_INPUT_BUFFER_PADDING_SIZE 16
535 * @ingroup lavc_encoding
536 * minimum encoding buffer size
537 * Used to avoid some checks during header writing.
539 #define FF_MIN_BUFFER_SIZE 16384
543 * @ingroup lavc_encoding
544 * motion estimation type.
547 ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
551 ME_EPZS, ///< enhanced predictive zonal search
552 ME_X1, ///< reserved for experiments
553 ME_HEX, ///< hexagon based search
554 ME_UMH, ///< uneven multi-hexagon search
555 ME_ITER, ///< iterative search
556 ME_TESA, ///< transformed exhaustive search algorithm
560 * @ingroup lavc_decoding
563 /* We leave some space between them for extensions (drop some
564 * keyframes for intra-only or drop just some bidir frames). */
565 AVDISCARD_NONE =-16, ///< discard nothing
566 AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
567 AVDISCARD_NONREF = 8, ///< discard all non reference
568 AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
569 AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
570 AVDISCARD_ALL = 48, ///< discard all
573 enum AVColorPrimaries{
574 AVCOL_PRI_BT709 = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 / SMPTE RP177 Annex B
575 AVCOL_PRI_UNSPECIFIED = 2,
576 AVCOL_PRI_BT470M = 4,
577 AVCOL_PRI_BT470BG = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM
578 AVCOL_PRI_SMPTE170M = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC
579 AVCOL_PRI_SMPTE240M = 7, ///< functionally identical to above
581 AVCOL_PRI_NB , ///< Not part of ABI
584 enum AVColorTransferCharacteristic{
585 AVCOL_TRC_BT709 = 1, ///< also ITU-R BT1361
586 AVCOL_TRC_UNSPECIFIED = 2,
587 AVCOL_TRC_GAMMA22 = 4, ///< also ITU-R BT470M / ITU-R BT1700 625 PAL & SECAM
588 AVCOL_TRC_GAMMA28 = 5, ///< also ITU-R BT470BG
589 AVCOL_TRC_SMPTE240M = 7,
590 AVCOL_TRC_NB , ///< Not part of ABI
595 AVCOL_SPC_BT709 = 1, ///< also ITU-R BT1361 / IEC 61966-2-4 xvYCC709 / SMPTE RP177 Annex B
596 AVCOL_SPC_UNSPECIFIED = 2,
598 AVCOL_SPC_BT470BG = 5, ///< also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM / IEC 61966-2-4 xvYCC601
599 AVCOL_SPC_SMPTE170M = 6, ///< also ITU-R BT601-6 525 / ITU-R BT1358 525 / ITU-R BT1700 NTSC / functionally identical to above
600 AVCOL_SPC_SMPTE240M = 7,
601 AVCOL_SPC_YCOCG = 8, ///< Used by Dirac / VC-2 and H.264 FRext, see ITU-T SG16
602 AVCOL_SPC_NB , ///< Not part of ABI
604 #define AVCOL_SPC_YCGCO AVCOL_SPC_YCOCG
607 AVCOL_RANGE_UNSPECIFIED = 0,
608 AVCOL_RANGE_MPEG = 1, ///< the normal 219*2^(n-8) "MPEG" YUV ranges
609 AVCOL_RANGE_JPEG = 2, ///< the normal 2^n-1 "JPEG" YUV ranges
610 AVCOL_RANGE_NB , ///< Not part of ABI
614 * X X 3 4 X X are luma samples,
615 * 1 2 1-6 are possible chroma positions
616 * X X 5 6 X 0 is undefined/unknown position
618 enum AVChromaLocation{
619 AVCHROMA_LOC_UNSPECIFIED = 0,
620 AVCHROMA_LOC_LEFT = 1, ///< mpeg2/4, h264 default
621 AVCHROMA_LOC_CENTER = 2, ///< mpeg1, jpeg, h263
622 AVCHROMA_LOC_TOPLEFT = 3, ///< DV
623 AVCHROMA_LOC_TOP = 4,
624 AVCHROMA_LOC_BOTTOMLEFT = 5,
625 AVCHROMA_LOC_BOTTOM = 6,
626 AVCHROMA_LOC_NB , ///< Not part of ABI
629 enum AVAudioServiceType {
630 AV_AUDIO_SERVICE_TYPE_MAIN = 0,
631 AV_AUDIO_SERVICE_TYPE_EFFECTS = 1,
632 AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
633 AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED = 3,
634 AV_AUDIO_SERVICE_TYPE_DIALOGUE = 4,
635 AV_AUDIO_SERVICE_TYPE_COMMENTARY = 5,
636 AV_AUDIO_SERVICE_TYPE_EMERGENCY = 6,
637 AV_AUDIO_SERVICE_TYPE_VOICE_OVER = 7,
638 AV_AUDIO_SERVICE_TYPE_KARAOKE = 8,
639 AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
643 * @ingroup lavc_encoding
645 typedef struct RcOverride{
648 int qscale; // If this is 0 then quality_factor will be used instead.
649 float quality_factor;
652 #define FF_MAX_B_FRAMES 16
655 These flags can be passed in AVCodecContext.flags before initialization.
656 Note: Not everything is supported yet.
659 #define CODEC_FLAG_QSCALE 0x0002 ///< Use fixed qscale.
660 #define CODEC_FLAG_4MV 0x0004 ///< 4 MV per MB allowed / advanced prediction for H.263.
661 #define CODEC_FLAG_QPEL 0x0010 ///< Use qpel MC.
662 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
663 #define CODEC_FLAG_MV0 0x0040 ///< Always try a MB with MV=<0,0>.
665 * The parent program guarantees that the input for B-frames containing
666 * streams is not written to for at least s->max_b_frames+1 frames, if
667 * this is not set the input will be copied.
669 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
670 #define CODEC_FLAG_PASS1 0x0200 ///< Use internal 2pass ratecontrol in first pass mode.
671 #define CODEC_FLAG_PASS2 0x0400 ///< Use internal 2pass ratecontrol in second pass mode.
672 #define CODEC_FLAG_GRAY 0x2000 ///< Only decode/encode grayscale.
673 #define CODEC_FLAG_EMU_EDGE 0x4000 ///< Don't draw edges.
674 #define CODEC_FLAG_PSNR 0x8000 ///< error[?] variables will be set during encoding.
675 #define CODEC_FLAG_TRUNCATED 0x00010000 /** Input bitstream might be truncated at a random
676 location instead of only at frame boundaries. */
677 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000 ///< Normalize adaptive quantization.
678 #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
679 #define CODEC_FLAG_LOW_DELAY 0x00080000 ///< Force low delay.
680 #define CODEC_FLAG_GLOBAL_HEADER 0x00400000 ///< Place global headers in extradata instead of every keyframe.
681 #define CODEC_FLAG_BITEXACT 0x00800000 ///< Use only bitexact stuff (except (I)DCT).
682 /* Fx : Flag for h263+ extra options */
683 #define CODEC_FLAG_AC_PRED 0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
684 #define CODEC_FLAG_LOOP_FILTER 0x00000800 ///< loop filter
685 #define CODEC_FLAG_INTERLACED_ME 0x20000000 ///< interlaced motion estimation
686 #define CODEC_FLAG_CLOSED_GOP 0x80000000
687 #define CODEC_FLAG2_FAST 0x00000001 ///< Allow non spec compliant speedup tricks.
688 #define CODEC_FLAG2_NO_OUTPUT 0x00000004 ///< Skip bitstream encoding.
689 #define CODEC_FLAG2_LOCAL_HEADER 0x00000008 ///< Place global headers at every keyframe instead of in extradata.
690 #define CODEC_FLAG2_DROP_FRAME_TIMECODE 0x00002000 ///< timecode is in drop frame format. DEPRECATED!!!!
691 #if FF_API_MPV_GLOBAL_OPTS
692 #define CODEC_FLAG_CBP_RD 0x04000000 ///< Use rate distortion optimization for cbp.
693 #define CODEC_FLAG_QP_RD 0x08000000 ///< Use rate distortion optimization for qp selectioon.
694 #define CODEC_FLAG2_STRICT_GOP 0x00000002 ///< Strictly enforce GOP size.
695 #define CODEC_FLAG2_SKIP_RD 0x00004000 ///< RD optimal MB level residual skipping
697 #define CODEC_FLAG2_CHUNKS 0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
698 #define CODEC_FLAG2_SHOW_ALL 0x00400000 ///< Show all frames before the first keyframe
700 /* Unsupported options :
701 * Syntax Arithmetic coding (SAC)
702 * Reference Picture Selection
703 * Independent Segment Decoding */
705 /* codec capabilities */
707 #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
709 * Codec uses get_buffer() for allocating buffers and supports custom allocators.
710 * If not set, it might not use get_buffer() at all or use operations that
711 * assume the buffer was allocated by avcodec_default_get_buffer.
713 #define CODEC_CAP_DR1 0x0002
714 #define CODEC_CAP_TRUNCATED 0x0008
715 /* Codec can export data for HW decoding (XvMC). */
716 #define CODEC_CAP_HWACCEL 0x0010
718 * Encoder or decoder requires flushing with NULL input at the end in order to
719 * give the complete and correct output.
721 * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
722 * with NULL data. The user can still send NULL data to the public encode
723 * or decode function, but libavcodec will not pass it along to the codec
724 * unless this flag is set.
727 * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
728 * avpkt->size=0 at the end to get the delayed data until the decoder no longer
732 * The encoder needs to be fed with NULL data at the end of encoding until the
733 * encoder no longer returns data.
735 * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
736 * flag also means that the encoder must set the pts and duration for
737 * each output packet. If this flag is not set, the pts and duration will
738 * be determined by libavcodec from the input frame.
740 #define CODEC_CAP_DELAY 0x0020
742 * Codec can be fed a final frame with a smaller size.
743 * This can be used to prevent truncation of the last audio samples.
745 #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
747 * Codec can export data for HW decoding (VDPAU).
749 #define CODEC_CAP_HWACCEL_VDPAU 0x0080
751 * Codec can output multiple frames per AVPacket
752 * Normally demuxers return one frame at a time, demuxers which do not do
753 * are connected to a parser to split what they return into proper frames.
754 * This flag is reserved to the very rare category of codecs which have a
755 * bitstream that cannot be split into frames without timeconsuming
756 * operations like full decoding. Demuxers carring such bitstreams thus
757 * may return multiple frames in a packet. This has many disadvantages like
758 * prohibiting stream copy in many cases thus it should only be considered
761 #define CODEC_CAP_SUBFRAMES 0x0100
763 * Codec is experimental and is thus avoided in favor of non experimental
766 #define CODEC_CAP_EXPERIMENTAL 0x0200
768 * Codec should fill in channel configuration and samplerate instead of container
770 #define CODEC_CAP_CHANNEL_CONF 0x0400
773 * Codec is able to deal with negative linesizes
775 #define CODEC_CAP_NEG_LINESIZES 0x0800
778 * Codec supports frame-level multithreading.
780 #define CODEC_CAP_FRAME_THREADS 0x1000
782 * Codec supports slice-based (or partition-based) multithreading.
784 #define CODEC_CAP_SLICE_THREADS 0x2000
786 * Codec supports changed parameters at any point.
788 #define CODEC_CAP_PARAM_CHANGE 0x4000
790 * Codec supports avctx->thread_count == 0 (auto).
792 #define CODEC_CAP_AUTO_THREADS 0x8000
794 * Audio encoder supports receiving a different number of samples in each call.
796 #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
798 * Codec is intra only.
800 #define CODEC_CAP_INTRA_ONLY 0x40000000
804 #define CODEC_CAP_LOSSLESS 0x80000000
806 //The following defines may change, don't expect compatibility if you use them.
807 #define MB_TYPE_INTRA4x4 0x0001
808 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
809 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
810 #define MB_TYPE_16x16 0x0008
811 #define MB_TYPE_16x8 0x0010
812 #define MB_TYPE_8x16 0x0020
813 #define MB_TYPE_8x8 0x0040
814 #define MB_TYPE_INTERLACED 0x0080
815 #define MB_TYPE_DIRECT2 0x0100 //FIXME
816 #define MB_TYPE_ACPRED 0x0200
817 #define MB_TYPE_GMC 0x0400
818 #define MB_TYPE_SKIP 0x0800
819 #define MB_TYPE_P0L0 0x1000
820 #define MB_TYPE_P1L0 0x2000
821 #define MB_TYPE_P0L1 0x4000
822 #define MB_TYPE_P1L1 0x8000
823 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
824 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
825 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
826 #define MB_TYPE_QUANT 0x00010000
827 #define MB_TYPE_CBP 0x00020000
828 //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
832 * This specifies the area which should be displayed.
833 * Note there may be multiple such areas for one frame.
835 typedef struct AVPanScan{
838 * - encoding: Set by user.
839 * - decoding: Set by libavcodec.
844 * width and height in 1/16 pel
845 * - encoding: Set by user.
846 * - decoding: Set by libavcodec.
852 * position of the top left corner in 1/16 pel for up to 3 fields/frames
853 * - encoding: Set by user.
854 * - decoding: Set by libavcodec.
856 int16_t position[3][2];
859 #define FF_QSCALE_TYPE_MPEG1 0
860 #define FF_QSCALE_TYPE_MPEG2 1
861 #define FF_QSCALE_TYPE_H264 2
862 #define FF_QSCALE_TYPE_VP56 3
864 #define FF_BUFFER_TYPE_INTERNAL 1
865 #define FF_BUFFER_TYPE_USER 2 ///< direct rendering buffers (image is (de)allocated by user)
866 #define FF_BUFFER_TYPE_SHARED 4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
867 #define FF_BUFFER_TYPE_COPY 8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
869 #define FF_BUFFER_HINTS_VALID 0x01 // Buffer hints value is meaningful (if 0 ignore).
870 #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
871 #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
872 #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
875 * @defgroup lavc_packet AVPacket
877 * Types and functions for working with AVPacket.
880 enum AVPacketSideDataType {
882 AV_PKT_DATA_NEW_EXTRADATA,
885 * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
888 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
889 * s32le channel_count
890 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
891 * u64le channel_layout
892 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
894 * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
899 AV_PKT_DATA_PARAM_CHANGE,
902 * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
903 * structures with info about macroblocks relevant to splitting the
904 * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
905 * That is, it does not necessarily contain info about all macroblocks,
906 * as long as the distance between macroblocks in the info is smaller
907 * than the target payload size.
908 * Each MB info structure is 12 bytes, and is laid out as follows:
910 * u32le bit offset from the start of the packet
911 * u8 current quantizer at the start of the macroblock
913 * u16le macroblock address within the GOB
914 * u8 horizontal MV predictor
915 * u8 vertical MV predictor
916 * u8 horizontal MV predictor for block number 3
917 * u8 vertical MV predictor for block number 3
920 AV_PKT_DATA_H263_MB_INFO,
923 * Recommmends skipping the specified number of samples
925 * u32le number of samples to skip from start of this packet
926 * u32le number of samples to skip from end of this packet
927 * u8 reason for start skip
928 * u8 reason for end skip (0=padding silence, 1=convergence)
931 AV_PKT_DATA_SKIP_SAMPLES=70,
934 * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
935 * the packet may contain "dual mono" audio specific to Japanese DTV
936 * and if it is true, recommends only the selected channel to be used.
938 * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
941 AV_PKT_DATA_JP_DUALMONO,
944 typedef struct AVPacket {
946 * Presentation timestamp in AVStream->time_base units; the time at which
947 * the decompressed packet will be presented to the user.
948 * Can be AV_NOPTS_VALUE if it is not stored in the file.
949 * pts MUST be larger or equal to dts as presentation cannot happen before
950 * decompression, unless one wants to view hex dumps. Some formats misuse
951 * the terms dts and pts/cts to mean something different. Such timestamps
952 * must be converted to true pts/dts before they are stored in AVPacket.
956 * Decompression timestamp in AVStream->time_base units; the time at which
957 * the packet is decompressed.
958 * Can be AV_NOPTS_VALUE if it is not stored in the file.
965 * A combination of AV_PKT_FLAG values
969 * Additional packet data that can be provided by the container.
970 * Packet can contain several types of side information.
975 enum AVPacketSideDataType type;
980 * Duration of this packet in AVStream->time_base units, 0 if unknown.
981 * Equals next_pts - this_pts in presentation order.
984 void (*destruct)(struct AVPacket *);
986 int64_t pos; ///< byte position in stream, -1 if unknown
989 * Time difference in AVStream->time_base units from the pts of this
990 * packet to the point at which the output from the decoder has converged
991 * independent from the availability of previous frames. That is, the
992 * frames are virtually identical no matter if decoding started from
993 * the very first frame or from this keyframe.
994 * Is AV_NOPTS_VALUE if unknown.
995 * This field is not the display duration of the current packet.
996 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
999 * The purpose of this field is to allow seeking in streams that have no
1000 * keyframes in the conventional sense. It corresponds to the
1001 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
1002 * essential for some types of subtitle streams to ensure that all
1003 * subtitles are correctly displayed after seeking.
1005 int64_t convergence_duration;
1007 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1008 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1010 enum AVSideDataParamChangeFlags {
1011 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT = 0x0001,
1012 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT = 0x0002,
1013 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE = 0x0004,
1014 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS = 0x0008,
1021 * Audio Video Frame.
1022 * New fields can be added to the end of AVFRAME with minor version
1023 * bumps. Similarly fields that are marked as to be only accessed by
1024 * av_opt_ptr() can be reordered. This allows 2 forks to add fields
1025 * without breaking compatibility with each other.
1026 * Removal, reordering and changes in the remaining cases require
1027 * a major version bump.
1028 * sizeof(AVFrame) must not be used outside libavcodec.
1030 typedef struct AVFrame {
1031 #define AV_NUM_DATA_POINTERS 8
1033 * pointer to the picture/channel planes.
1034 * This might be different from the first allocated byte
1035 * - encoding: Set by user
1036 * - decoding: set by AVCodecContext.get_buffer()
1038 uint8_t *data[AV_NUM_DATA_POINTERS];
1041 * Size, in bytes, of the data for each picture/channel plane.
1043 * For audio, only linesize[0] may be set. For planar audio, each channel
1044 * plane must be the same size.
1046 * - encoding: Set by user
1047 * - decoding: set by AVCodecContext.get_buffer()
1049 int linesize[AV_NUM_DATA_POINTERS];
1052 * pointers to the data planes/channels.
1054 * For video, this should simply point to data[].
1056 * For planar audio, each channel has a separate data pointer, and
1057 * linesize[0] contains the size of each channel buffer.
1058 * For packed audio, there is just one data pointer, and linesize[0]
1059 * contains the total size of the buffer for all channels.
1061 * Note: Both data and extended_data will always be set by get_buffer(),
1062 * but for planar audio with more channels that can fit in data,
1063 * extended_data must be used by the decoder in order to access all
1067 * decoding: set by AVCodecContext.get_buffer()
1069 uint8_t **extended_data;
1072 * width and height of the video frame
1073 * - encoding: unused
1074 * - decoding: Read by user.
1079 * number of audio samples (per channel) described by this frame
1080 * - encoding: Set by user
1081 * - decoding: Set by libavcodec
1086 * format of the frame, -1 if unknown or unset
1087 * Values correspond to enum PixelFormat for video frames,
1088 * enum AVSampleFormat for audio)
1089 * - encoding: unused
1090 * - decoding: Read by user.
1095 * 1 -> keyframe, 0-> not
1096 * - encoding: Set by libavcodec.
1097 * - decoding: Set by libavcodec.
1102 * Picture type of the frame, see ?_TYPE below.
1103 * - encoding: Set by libavcodec. for coded_picture (and set by user for input).
1104 * - decoding: Set by libavcodec.
1106 enum AVPictureType pict_type;
1109 * pointer to the first allocated byte of the picture. Can be used in get_buffer/release_buffer.
1110 * This isn't used by libavcodec unless the default get/release_buffer() is used.
1114 uint8_t *base[AV_NUM_DATA_POINTERS];
1117 * sample aspect ratio for the video frame, 0/1 if unknown/unspecified
1118 * - encoding: unused
1119 * - decoding: Read by user.
1121 AVRational sample_aspect_ratio;
1124 * presentation timestamp in time_base units (time when frame should be shown to user)
1125 * If AV_NOPTS_VALUE then frame_rate = 1/time_base will be assumed.
1126 * - encoding: MUST be set by user.
1127 * - decoding: Set by libavcodec.
1132 * reordered pts from the last AVPacket that has been input into the decoder
1133 * - encoding: unused
1134 * - decoding: Read by user.
1139 * dts from the last AVPacket that has been input into the decoder
1140 * - encoding: unused
1141 * - decoding: Read by user.
1146 * picture number in bitstream order
1147 * - encoding: set by
1148 * - decoding: Set by libavcodec.
1150 int coded_picture_number;
1152 * picture number in display order
1153 * - encoding: set by
1154 * - decoding: Set by libavcodec.
1156 int display_picture_number;
1159 * quality (between 1 (good) and FF_LAMBDA_MAX (bad))
1160 * - encoding: Set by libavcodec. for coded_picture (and set by user for input).
1161 * - decoding: Set by libavcodec.
1166 * is this picture used as reference
1167 * The values for this are the same as the MpegEncContext.picture_structure
1168 * variable, that is 1->top field, 2->bottom field, 3->frame/both fields.
1169 * Set to 4 for delayed, non-reference frames.
1170 * - encoding: unused
1171 * - decoding: Set by libavcodec. (before get_buffer() call)).
1177 * - encoding: unused
1178 * - decoding: Set by libavcodec.
1180 int8_t *qscale_table;
1183 * - encoding: unused
1184 * - decoding: Set by libavcodec.
1194 * mbskip_table[mb]>=1 if MB didn't change
1195 * stride= mb_width = (width+15)>>4
1196 * - encoding: unused
1197 * - decoding: Set by libavcodec.
1199 uint8_t *mbskip_table;
1202 * motion vector table
1205 * int mv_sample_log2= 4 - motion_subsample_log2;
1206 * int mb_width= (width+15)>>4;
1207 * int mv_stride= (mb_width << mv_sample_log2) + 1;
1208 * motion_val[direction][x + y*mv_stride][0->mv_x, 1->mv_y];
1210 * - encoding: Set by user.
1211 * - decoding: Set by libavcodec.
1213 int16_t (*motion_val[2])[2];
1216 * macroblock type table
1217 * mb_type_base + mb_width + 2
1218 * - encoding: Set by user.
1219 * - decoding: Set by libavcodec.
1225 * - encoding: unused
1226 * - decoding: Set by libavcodec.
1231 * motion reference frame index
1232 * the order in which these are stored can depend on the codec.
1233 * - encoding: Set by user.
1234 * - decoding: Set by libavcodec.
1236 int8_t *ref_index[2];
1239 * for some private data of the user
1240 * - encoding: unused
1241 * - decoding: Set by user.
1247 * - encoding: Set by libavcodec. if flags&CODEC_FLAG_PSNR.
1248 * - decoding: unused
1250 uint64_t error[AV_NUM_DATA_POINTERS];
1253 * type of the buffer (to keep track of who has to deallocate data[*])
1254 * - encoding: Set by the one who allocates it.
1255 * - decoding: Set by the one who allocates it.
1256 * Note: User allocated (direct rendering) & internal buffers cannot coexist currently.
1261 * When decoding, this signals how much the picture must be delayed.
1262 * extra_delay = repeat_pict / (2*fps)
1263 * - encoding: unused
1264 * - decoding: Set by libavcodec.
1269 * The content of the picture is interlaced.
1270 * - encoding: Set by user.
1271 * - decoding: Set by libavcodec. (default 0)
1273 int interlaced_frame;
1276 * If the content is interlaced, is top field displayed first.
1277 * - encoding: Set by user.
1278 * - decoding: Set by libavcodec.
1280 int top_field_first;
1283 * Tell user application that palette has changed from previous frame.
1284 * - encoding: ??? (no palette-enabled encoder yet)
1285 * - decoding: Set by libavcodec. (default 0).
1287 int palette_has_changed;
1290 * codec suggestion on buffer type if != 0
1291 * - encoding: unused
1292 * - decoding: Set by libavcodec. (before get_buffer() call)).
1298 * - encoding: Set by user.
1299 * - decoding: Set by libavcodec.
1301 AVPanScan *pan_scan;
1304 * reordered opaque 64bit (generally an integer or a double precision float
1305 * PTS but can be anything).
1306 * The user sets AVCodecContext.reordered_opaque to represent the input at
1308 * the decoder reorders values as needed and sets AVFrame.reordered_opaque
1309 * to exactly one of the values provided by the user through AVCodecContext.reordered_opaque
1310 * @deprecated in favor of pkt_pts
1311 * - encoding: unused
1312 * - decoding: Read by user.
1314 int64_t reordered_opaque;
1317 * hardware accelerator private data (FFmpeg-allocated)
1318 * - encoding: unused
1319 * - decoding: Set by libavcodec
1321 void *hwaccel_picture_private;
1324 * the AVCodecContext which ff_thread_get_buffer() was last called on
1325 * - encoding: Set by libavcodec.
1326 * - decoding: Set by libavcodec.
1328 struct AVCodecContext *owner;
1331 * used by multithreading to store frame-specific info
1332 * - encoding: Set by libavcodec.
1333 * - decoding: Set by libavcodec.
1335 void *thread_opaque;
1338 * log2 of the size of the block which a single vector in motion_val represents:
1339 * (4->16x16, 3->8x8, 2-> 4x4, 1-> 2x2)
1340 * - encoding: unused
1341 * - decoding: Set by libavcodec.
1343 uint8_t motion_subsample_log2;
1346 * Sample rate of the audio data.
1348 * - encoding: unused
1349 * - decoding: read by user
1354 * Channel layout of the audio data.
1356 * - encoding: unused
1357 * - decoding: read by user.
1359 uint64_t channel_layout;
1362 * frame timestamp estimated using various heuristics, in stream time base
1363 * Code outside libavcodec should access this field using:
1364 * av_frame_get_best_effort_timestamp(frame)
1365 * - encoding: unused
1366 * - decoding: set by libavcodec, read by user.
1368 int64_t best_effort_timestamp;
1371 * reordered pos from the last AVPacket that has been input into the decoder
1372 * Code outside libavcodec should access this field using:
1373 * av_frame_get_pkt_pos(frame)
1374 * - encoding: unused
1375 * - decoding: Read by user.
1380 * duration of the corresponding packet, expressed in
1381 * AVStream->time_base units, 0 if unknown.
1382 * Code outside libavcodec should access this field using:
1383 * av_frame_get_pkt_duration(frame)
1384 * - encoding: unused
1385 * - decoding: Read by user.
1387 int64_t pkt_duration;
1391 * Code outside libavcodec should access this field using:
1392 * av_frame_get_metadata(frame)
1393 * - encoding: Set by user.
1394 * - decoding: Set by libavcodec.
1396 AVDictionary *metadata;
1399 * decode error flags of the frame, set to a combination of
1400 * FF_DECODE_ERROR_xxx flags if the decoder produced a frame, but there
1401 * were errors during the decoding.
1402 * Code outside libavcodec should access this field using:
1403 * av_frame_get_decode_error_flags(frame)
1404 * - encoding: unused
1405 * - decoding: set by libavcodec, read by user.
1407 int decode_error_flags;
1408 #define FF_DECODE_ERROR_INVALID_BITSTREAM 1
1409 #define FF_DECODE_ERROR_MISSING_REFERENCE 2
1412 * number of audio channels, only used for audio.
1413 * Code outside libavcodec should access this field using:
1414 * av_frame_get_channels(frame)
1415 * - encoding: unused
1416 * - decoding: Read by user.
1422 * Accessors for some AVFrame fields.
1423 * The position of these field in the structure is not part of the ABI,
1424 * they should not be accessed directly outside libavcodec.
1426 int64_t av_frame_get_best_effort_timestamp(const AVFrame *frame);
1427 void av_frame_set_best_effort_timestamp(AVFrame *frame, int64_t val);
1428 int64_t av_frame_get_pkt_duration (const AVFrame *frame);
1429 void av_frame_set_pkt_duration (AVFrame *frame, int64_t val);
1430 int64_t av_frame_get_pkt_pos (const AVFrame *frame);
1431 void av_frame_set_pkt_pos (AVFrame *frame, int64_t val);
1432 int64_t av_frame_get_channel_layout (const AVFrame *frame);
1433 void av_frame_set_channel_layout (AVFrame *frame, int64_t val);
1434 int av_frame_get_channels (const AVFrame *frame);
1435 void av_frame_set_channels (AVFrame *frame, int val);
1436 int av_frame_get_sample_rate (const AVFrame *frame);
1437 void av_frame_set_sample_rate (AVFrame *frame, int val);
1438 AVDictionary *av_frame_get_metadata (const AVFrame *frame);
1439 void av_frame_set_metadata (AVFrame *frame, AVDictionary *val);
1440 int av_frame_get_decode_error_flags (const AVFrame *frame);
1441 void av_frame_set_decode_error_flags (AVFrame *frame, int val);
1443 struct AVCodecInternal;
1447 AV_FIELD_PROGRESSIVE,
1448 AV_FIELD_TT, //< Top coded_first, top displayed first
1449 AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1450 AV_FIELD_TB, //< Top coded first, bottom displayed first
1451 AV_FIELD_BT, //< Bottom coded first, top displayed first
1455 * main external API structure.
1456 * New fields can be added to the end with minor version bumps.
1457 * Removal, reordering and changes to existing fields require a major
1459 * Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1461 * sizeof(AVCodecContext) must not be used outside libav*.
1463 typedef struct AVCodecContext {
1465 * information on struct for av_log
1466 * - set by avcodec_alloc_context3
1468 const AVClass *av_class;
1469 int log_level_offset;
1471 enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1472 const struct AVCodec *codec;
1473 char codec_name[32];
1474 enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1477 * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1478 * This is used to work around some encoder bugs.
1479 * A demuxer should set this to what is stored in the field used to identify the codec.
1480 * If there are multiple such fields in a container then the demuxer should choose the one
1481 * which maximizes the information about the used codec.
1482 * If the codec tag field in a container is larger than 32 bits then the demuxer should
1483 * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1484 * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1486 * - encoding: Set by user, if not then the default based on codec_id will be used.
1487 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1489 unsigned int codec_tag;
1492 * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1493 * This is used to work around some encoder bugs.
1494 * - encoding: unused
1495 * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1497 unsigned int stream_codec_tag;
1501 * @deprecated this field is unused
1503 attribute_deprecated int sub_id;
1509 * Private context used for internal data.
1511 * Unlike priv_data, this is not codec-specific. It is used in general
1512 * libavcodec functions.
1514 struct AVCodecInternal *internal;
1517 * Private data of the user, can be used to carry app specific stuff.
1518 * - encoding: Set by user.
1519 * - decoding: Set by user.
1524 * the average bitrate
1525 * - encoding: Set by user; unused for constant quantizer encoding.
1526 * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
1531 * number of bits the bitstream is allowed to diverge from the reference.
1532 * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1533 * - encoding: Set by user; unused for constant quantizer encoding.
1534 * - decoding: unused
1536 int bit_rate_tolerance;
1539 * Global quality for codecs which cannot change it per frame.
1540 * This should be proportional to MPEG-1/2/4 qscale.
1541 * - encoding: Set by user.
1542 * - decoding: unused
1547 * - encoding: Set by user.
1548 * - decoding: unused
1550 int compression_level;
1551 #define FF_COMPRESSION_DEFAULT -1
1555 * - encoding: Set by user.
1556 * - decoding: Set by user.
1562 * - encoding: Set by user.
1563 * - decoding: Set by user.
1568 * some codecs need / can use extradata like Huffman tables.
1569 * mjpeg: Huffman tables
1570 * rv10: additional flags
1571 * mpeg4: global headers (they can be in the bitstream or here)
1572 * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
1573 * than extradata_size to avoid prolems if it is read with the bitstream reader.
1574 * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1575 * - encoding: Set/allocated/freed by libavcodec.
1576 * - decoding: Set/allocated/freed by user.
1582 * This is the fundamental unit of time (in seconds) in terms
1583 * of which frame timestamps are represented. For fixed-fps content,
1584 * timebase should be 1/framerate and timestamp increments should be
1586 * - encoding: MUST be set by user.
1587 * - decoding: Set by libavcodec.
1589 AVRational time_base;
1592 * For some codecs, the time base is closer to the field rate than the frame rate.
1593 * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1594 * if no telecine is used ...
1596 * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1598 int ticks_per_frame;
1601 * Encoding: Number of frames delay there will be from the encoder input to
1602 * the decoder output. (we assume the decoder matches the spec)
1603 * Decoding: Number of frames delay in addition to what a standard decoder
1604 * as specified in the spec would produce.
1607 * Number of frames the decoded output will be delayed relative to the
1611 * For encoding, this is the number of "priming" samples added to the
1612 * beginning of the stream. The decoded output will be delayed by this
1613 * many samples relative to the input to the encoder. Note that this
1614 * field is purely informational and does not directly affect the pts
1615 * output by the encoder, which should always be based on the actual
1616 * presentation time, including any delay.
1617 * For decoding, this is the number of samples the decoder needs to
1618 * output before the decoder's output is valid. When seeking, you should
1619 * start decoding this many samples prior to your desired seek point.
1621 * - encoding: Set by libavcodec.
1622 * - decoding: Set by libavcodec.
1629 * picture width / height.
1630 * - encoding: MUST be set by user.
1631 * - decoding: Set by libavcodec.
1632 * Note: For compatibility it is possible to set this instead of
1633 * coded_width/height before decoding.
1638 * Bitstream width / height, may be different from width/height if lowres enabled.
1639 * - encoding: unused
1640 * - decoding: Set by user before init if known. Codec should override / dynamically change if needed.
1642 int coded_width, coded_height;
1644 #define FF_ASPECT_EXTENDED 15
1647 * the number of pictures in a group of pictures, or 0 for intra_only
1648 * - encoding: Set by user.
1649 * - decoding: unused
1654 * Pixel format, see PIX_FMT_xxx.
1655 * May be set by the demuxer if known from headers.
1656 * May be overridden by the decoder if it knows better.
1657 * - encoding: Set by user.
1658 * - decoding: Set by user if known, overridden by libavcodec if known
1660 enum PixelFormat pix_fmt;
1663 * Motion estimation algorithm used for video coding.
1664 * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
1665 * 8 (umh), 9 (iter), 10 (tesa) [7, 8, 10 are x264 specific, 9 is snow specific]
1666 * - encoding: MUST be set by user.
1667 * - decoding: unused
1672 * If non NULL, 'draw_horiz_band' is called by the libavcodec
1673 * decoder to draw a horizontal band. It improves cache usage. Not
1674 * all codecs can do that. You must check the codec capabilities
1676 * When multithreading is used, it may be called from multiple threads
1677 * at the same time; threads might draw different parts of the same AVFrame,
1678 * or multiple AVFrames, and there is no guarantee that slices will be drawn
1680 * The function is also used by hardware acceleration APIs.
1681 * It is called at least once during frame decoding to pass
1682 * the data needed for hardware render.
1683 * In that mode instead of pixel data, AVFrame points to
1684 * a structure specific to the acceleration API. The application
1685 * reads the structure and can change some fields to indicate progress
1687 * - encoding: unused
1688 * - decoding: Set by user.
1689 * @param height the height of the slice
1690 * @param y the y position of the slice
1691 * @param type 1->top field, 2->bottom field, 3->frame
1692 * @param offset offset into the AVFrame.data from which the slice should be read
1694 void (*draw_horiz_band)(struct AVCodecContext *s,
1695 const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1696 int y, int type, int height);
1699 * callback to negotiate the pixelFormat
1700 * @param fmt is the list of formats which are supported by the codec,
1701 * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1702 * The first is always the native one.
1703 * @return the chosen format
1704 * - encoding: unused
1705 * - decoding: Set by user, if not set the native format will be chosen.
1707 enum PixelFormat (*get_format)(struct AVCodecContext *s, const enum PixelFormat * fmt);
1710 * maximum number of B-frames between non-B-frames
1711 * Note: The output will be delayed by max_b_frames+1 relative to the input.
1712 * - encoding: Set by user.
1713 * - decoding: unused
1718 * qscale factor between IP and B-frames
1719 * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1720 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1721 * - encoding: Set by user.
1722 * - decoding: unused
1724 float b_quant_factor;
1726 /** obsolete FIXME remove */
1728 #define FF_RC_STRATEGY_XVID 1
1730 int b_frame_strategy;
1732 #if FF_API_MPV_GLOBAL_OPTS
1734 * luma single coefficient elimination threshold
1735 * - encoding: Set by user.
1736 * - decoding: unused
1738 attribute_deprecated int luma_elim_threshold;
1741 * chroma single coeff elimination threshold
1742 * - encoding: Set by user.
1743 * - decoding: unused
1745 attribute_deprecated int chroma_elim_threshold;
1749 * qscale offset between IP and B-frames
1750 * - encoding: Set by user.
1751 * - decoding: unused
1753 float b_quant_offset;
1756 * Size of the frame reordering buffer in the decoder.
1757 * For MPEG-2 it is 1 IPB or 0 low delay IP.
1758 * - encoding: Set by libavcodec.
1759 * - decoding: Set by libavcodec.
1764 * 0-> h263 quant 1-> mpeg quant
1765 * - encoding: Set by user.
1766 * - decoding: unused
1771 * qscale factor between P and I-frames
1772 * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
1773 * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1774 * - encoding: Set by user.
1775 * - decoding: unused
1777 float i_quant_factor;
1780 * qscale offset between P and I-frames
1781 * - encoding: Set by user.
1782 * - decoding: unused
1784 float i_quant_offset;
1787 * luminance masking (0-> disabled)
1788 * - encoding: Set by user.
1789 * - decoding: unused
1794 * temporary complexity masking (0-> disabled)
1795 * - encoding: Set by user.
1796 * - decoding: unused
1798 float temporal_cplx_masking;
1801 * spatial complexity masking (0-> disabled)
1802 * - encoding: Set by user.
1803 * - decoding: unused
1805 float spatial_cplx_masking;
1808 * p block masking (0-> disabled)
1809 * - encoding: Set by user.
1810 * - decoding: unused
1815 * darkness masking (0-> disabled)
1816 * - encoding: Set by user.
1817 * - decoding: unused
1823 * - encoding: Set by libavcodec.
1824 * - decoding: Set by user (or 0).
1828 * prediction method (needed for huffyuv)
1829 * - encoding: Set by user.
1830 * - decoding: unused
1832 int prediction_method;
1833 #define FF_PRED_LEFT 0
1834 #define FF_PRED_PLANE 1
1835 #define FF_PRED_MEDIAN 2
1838 * slice offsets in the frame in bytes
1839 * - encoding: Set/allocated by libavcodec.
1840 * - decoding: Set/allocated by user (or NULL).
1845 * sample aspect ratio (0 if unknown)
1846 * That is the width of a pixel divided by the height of the pixel.
1847 * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1848 * - encoding: Set by user.
1849 * - decoding: Set by libavcodec.
1851 AVRational sample_aspect_ratio;
1854 * motion estimation comparison function
1855 * - encoding: Set by user.
1856 * - decoding: unused
1860 * subpixel motion estimation comparison function
1861 * - encoding: Set by user.
1862 * - decoding: unused
1866 * macroblock comparison function (not supported yet)
1867 * - encoding: Set by user.
1868 * - decoding: unused
1872 * interlaced DCT comparison function
1873 * - encoding: Set by user.
1874 * - decoding: unused
1877 #define FF_CMP_SAD 0
1878 #define FF_CMP_SSE 1
1879 #define FF_CMP_SATD 2
1880 #define FF_CMP_DCT 3
1881 #define FF_CMP_PSNR 4
1882 #define FF_CMP_BIT 5
1884 #define FF_CMP_ZERO 7
1885 #define FF_CMP_VSAD 8
1886 #define FF_CMP_VSSE 9
1887 #define FF_CMP_NSSE 10
1888 #define FF_CMP_W53 11
1889 #define FF_CMP_W97 12
1890 #define FF_CMP_DCTMAX 13
1891 #define FF_CMP_DCT264 14
1892 #define FF_CMP_CHROMA 256
1895 * ME diamond size & shape
1896 * - encoding: Set by user.
1897 * - decoding: unused
1902 * amount of previous MV predictors (2a+1 x 2a+1 square)
1903 * - encoding: Set by user.
1904 * - decoding: unused
1906 int last_predictor_count;
1909 * prepass for motion estimation
1910 * - encoding: Set by user.
1911 * - decoding: unused
1916 * motion estimation prepass comparison function
1917 * - encoding: Set by user.
1918 * - decoding: unused
1923 * ME prepass diamond size & shape
1924 * - encoding: Set by user.
1925 * - decoding: unused
1931 * - encoding: Set by user.
1932 * - decoding: unused
1934 int me_subpel_quality;
1937 * DTG active format information (additional aspect ratio
1938 * information only used in DVB MPEG-2 transport streams)
1941 * - encoding: unused
1942 * - decoding: Set by decoder.
1944 int dtg_active_format;
1945 #define FF_DTG_AFD_SAME 8
1946 #define FF_DTG_AFD_4_3 9
1947 #define FF_DTG_AFD_16_9 10
1948 #define FF_DTG_AFD_14_9 11
1949 #define FF_DTG_AFD_4_3_SP_14_9 13
1950 #define FF_DTG_AFD_16_9_SP_14_9 14
1951 #define FF_DTG_AFD_SP_4_3 15
1954 * maximum motion estimation search range in subpel units
1955 * If 0 then no limit.
1957 * - encoding: Set by user.
1958 * - decoding: unused
1963 * intra quantizer bias
1964 * - encoding: Set by user.
1965 * - decoding: unused
1967 int intra_quant_bias;
1968 #define FF_DEFAULT_QUANT_BIAS 999999
1971 * inter quantizer bias
1972 * - encoding: Set by user.
1973 * - decoding: unused
1975 int inter_quant_bias;
1977 #if FF_API_COLOR_TABLE_ID
1980 * - encoding: unused
1981 * - decoding: Which clrtable should be used for 8bit RGB images.
1982 * Tables have to be stored somewhere. FIXME
1984 attribute_deprecated int color_table_id;
1989 * - encoding: unused
1990 * - decoding: Set by user.
1993 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1994 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
1995 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1998 * XVideo Motion Acceleration
1999 * - encoding: forbidden
2000 * - decoding: set by decoder
2002 int xvmc_acceleration;
2005 * macroblock decision mode
2006 * - encoding: Set by user.
2007 * - decoding: unused
2010 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2011 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2012 #define FF_MB_DECISION_RD 2 ///< rate distortion
2015 * custom intra quantization matrix
2016 * - encoding: Set by user, can be NULL.
2017 * - decoding: Set by libavcodec.
2019 uint16_t *intra_matrix;
2022 * custom inter quantization matrix
2023 * - encoding: Set by user, can be NULL.
2024 * - decoding: Set by libavcodec.
2026 uint16_t *inter_matrix;
2029 * scene change detection threshold
2030 * 0 is default, larger means fewer detected scene changes.
2031 * - encoding: Set by user.
2032 * - decoding: unused
2034 int scenechange_threshold;
2037 * noise reduction strength
2038 * - encoding: Set by user.
2039 * - decoding: unused
2041 int noise_reduction;
2043 #if FF_API_INTER_THRESHOLD
2045 * @deprecated this field is unused
2047 attribute_deprecated int inter_threshold;
2050 #if FF_API_MPV_GLOBAL_OPTS
2052 * @deprecated use mpegvideo private options instead
2054 attribute_deprecated int quantizer_noise_shaping;
2058 * Motion estimation threshold below which no motion estimation is
2059 * performed, but instead the user specified motion vectors are used.
2061 * - encoding: Set by user.
2062 * - decoding: unused
2067 * Macroblock threshold below which the user specified macroblock types will be used.
2068 * - encoding: Set by user.
2069 * - decoding: unused
2074 * precision of the intra DC coefficient - 8
2075 * - encoding: Set by user.
2076 * - decoding: unused
2078 int intra_dc_precision;
2081 * Number of macroblock rows at the top which are skipped.
2082 * - encoding: unused
2083 * - decoding: Set by user.
2088 * Number of macroblock rows at the bottom which are skipped.
2089 * - encoding: unused
2090 * - decoding: Set by user.
2095 * Border processing masking, raises the quantizer for mbs on the borders
2097 * - encoding: Set by user.
2098 * - decoding: unused
2100 float border_masking;
2103 * minimum MB lagrange multipler
2104 * - encoding: Set by user.
2105 * - decoding: unused
2110 * maximum MB lagrange multipler
2111 * - encoding: Set by user.
2112 * - decoding: unused
2118 * - encoding: Set by user.
2119 * - decoding: unused
2121 int me_penalty_compensation;
2125 * - encoding: Set by user.
2126 * - decoding: unused
2132 * - encoding: Set by user.
2133 * - decoding: unused
2139 * - encoding: Set by user.
2140 * - decoding: unused
2145 * number of reference frames
2146 * - encoding: Set by user.
2147 * - decoding: Set by lavc.
2152 * chroma qp offset from luma
2153 * - encoding: Set by user.
2154 * - decoding: unused
2159 * Multiplied by qscale for each frame and added to scene_change_score.
2160 * - encoding: Set by user.
2161 * - decoding: unused
2163 int scenechange_factor;
2167 * Note: Value depends upon the compare function used for fullpel ME.
2168 * - encoding: Set by user.
2169 * - decoding: unused
2174 * Adjust sensitivity of b_frame_strategy 1.
2175 * - encoding: Set by user.
2176 * - decoding: unused
2181 * Chromaticity coordinates of the source primaries.
2182 * - encoding: Set by user
2183 * - decoding: Set by libavcodec
2185 enum AVColorPrimaries color_primaries;
2188 * Color Transfer Characteristic.
2189 * - encoding: Set by user
2190 * - decoding: Set by libavcodec
2192 enum AVColorTransferCharacteristic color_trc;
2195 * YUV colorspace type.
2196 * - encoding: Set by user
2197 * - decoding: Set by libavcodec
2199 enum AVColorSpace colorspace;
2202 * MPEG vs JPEG YUV range.
2203 * - encoding: Set by user
2204 * - decoding: Set by libavcodec
2206 enum AVColorRange color_range;
2209 * This defines the location of chroma samples.
2210 * - encoding: Set by user
2211 * - decoding: Set by libavcodec
2213 enum AVChromaLocation chroma_sample_location;
2217 * Indicates number of picture subdivisions. Used for parallelized
2219 * - encoding: Set by user
2220 * - decoding: unused
2225 * - encoding: set by libavcodec
2226 * - decoding: Set by libavcodec
2228 enum AVFieldOrder field_order;
2231 int sample_rate; ///< samples per second
2232 int channels; ///< number of audio channels
2235 * audio sample format
2236 * - encoding: Set by user.
2237 * - decoding: Set by libavcodec.
2239 enum AVSampleFormat sample_fmt; ///< sample format
2241 /* The following data should not be initialized. */
2243 * Samples per packet, initialized when calling 'init'.
2248 * Frame counter, set by libavcodec.
2250 * - decoding: total number of frames returned from the decoder so far.
2251 * - encoding: total number of frames passed to the encoder so far.
2253 * @note the counter is not incremented if encoding/decoding resulted in
2259 * number of bytes per packet if constant and known or 0
2260 * Used by some WAV based audio codecs.
2265 * Audio cutoff bandwidth (0 means "automatic")
2266 * - encoding: Set by user.
2267 * - decoding: unused
2271 #if FF_API_REQUEST_CHANNELS
2273 * Decoder should decode to this many channels if it can (0 for default)
2274 * - encoding: unused
2275 * - decoding: Set by user.
2276 * @deprecated Deprecated in favor of request_channel_layout.
2278 int request_channels;
2282 * Audio channel layout.
2283 * - encoding: set by user.
2284 * - decoding: set by user, may be overwritten by libavcodec.
2286 uint64_t channel_layout;
2289 * Request decoder to use this channel layout if it can (0 for default)
2290 * - encoding: unused
2291 * - decoding: Set by user.
2293 uint64_t request_channel_layout;
2296 * Type of service that the audio stream conveys.
2297 * - encoding: Set by user.
2298 * - decoding: Set by libavcodec.
2300 enum AVAudioServiceType audio_service_type;
2303 * desired sample format
2304 * - encoding: Not used.
2305 * - decoding: Set by user.
2306 * Decoder will decode to this format if it can.
2308 enum AVSampleFormat request_sample_fmt;
2311 * Called at the beginning of each frame to get a buffer for it.
2313 * The function will set AVFrame.data[], AVFrame.linesize[].
2314 * AVFrame.extended_data[] must also be set, but it should be the same as
2315 * AVFrame.data[] except for planar audio with more channels than can fit
2316 * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
2317 * many data pointers as it can hold.
2319 * if CODEC_CAP_DR1 is not set then get_buffer() must call
2320 * avcodec_default_get_buffer() instead of providing buffers allocated by
2323 * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
2324 * need it. avcodec_default_get_buffer() aligns the output buffer properly,
2325 * but if get_buffer() is overridden then alignment considerations should
2326 * be taken into account.
2328 * @see avcodec_default_get_buffer()
2332 * If pic.reference is set then the frame will be read later by libavcodec.
2333 * avcodec_align_dimensions2() should be used to find the required width and
2334 * height, as they normally need to be rounded up to the next multiple of 16.
2336 * If frame multithreading is used and thread_safe_callbacks is set,
2337 * it may be called from a different thread, but not from more than one at
2338 * once. Does not need to be reentrant.
2340 * @see release_buffer(), reget_buffer()
2341 * @see avcodec_align_dimensions2()
2345 * Decoders request a buffer of a particular size by setting
2346 * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
2347 * however, utilize only part of the buffer by setting AVFrame.nb_samples
2348 * to a smaller value in the output frame.
2350 * Decoders cannot use the buffer after returning from
2351 * avcodec_decode_audio4(), so they will not call release_buffer(), as it
2352 * is assumed to be released immediately upon return.
2354 * As a convenience, av_samples_get_buffer_size() and
2355 * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
2356 * functions to find the required data size and to fill data pointers and
2357 * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2358 * since all planes must be the same size.
2360 * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2362 * - encoding: unused
2363 * - decoding: Set by libavcodec, user can override.
2365 int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
2368 * Called to release buffers which were allocated with get_buffer.
2369 * A released buffer can be reused in get_buffer().
2370 * pic.data[*] must be set to NULL.
2371 * May be called from a different thread if frame multithreading is used,
2372 * but not by more than one thread at once, so does not need to be reentrant.
2373 * - encoding: unused
2374 * - decoding: Set by libavcodec, user can override.
2376 void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
2379 * Called at the beginning of a frame to get cr buffer for it.
2380 * Buffer type (size, hints) must be the same. libavcodec won't check it.
2381 * libavcodec will pass previous buffer in pic, function should return
2382 * same buffer or new buffer with old frame "painted" into it.
2383 * If pic.data[0] == NULL must behave like get_buffer().
2384 * if CODEC_CAP_DR1 is not set then reget_buffer() must call
2385 * avcodec_default_reget_buffer() instead of providing buffers allocated by
2387 * - encoding: unused
2388 * - decoding: Set by libavcodec, user can override.
2390 int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
2393 /* - encoding parameters */
2394 float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2395 float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2399 * - encoding: Set by user.
2400 * - decoding: unused
2406 * - encoding: Set by user.
2407 * - decoding: unused
2412 * maximum quantizer difference between frames
2413 * - encoding: Set by user.
2414 * - decoding: unused
2419 * ratecontrol qmin qmax limiting method
2420 * 0-> clipping, 1-> use a nice continuous function to limit qscale wthin qmin/qmax.
2421 * - encoding: Set by user.
2422 * - decoding: unused
2430 * decoder bitstream buffer size
2431 * - encoding: Set by user.
2432 * - decoding: unused
2437 * ratecontrol override, see RcOverride
2438 * - encoding: Allocated/set/freed by user.
2439 * - decoding: unused
2441 int rc_override_count;
2442 RcOverride *rc_override;
2445 * rate control equation
2446 * - encoding: Set by user
2447 * - decoding: unused
2453 * - encoding: Set by user.
2454 * - decoding: unused
2460 * - encoding: Set by user.
2461 * - decoding: unused
2465 float rc_buffer_aggressivity;
2468 * initial complexity for pass1 ratecontrol
2469 * - encoding: Set by user.
2470 * - decoding: unused
2472 float rc_initial_cplx;
2475 * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2476 * - encoding: Set by user.
2477 * - decoding: unused.
2479 float rc_max_available_vbv_use;
2482 * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2483 * - encoding: Set by user.
2484 * - decoding: unused.
2486 float rc_min_vbv_overflow_use;
2489 * Number of bits which should be loaded into the rc buffer before decoding starts.
2490 * - encoding: Set by user.
2491 * - decoding: unused
2493 int rc_initial_buffer_occupancy;
2495 #define FF_CODER_TYPE_VLC 0
2496 #define FF_CODER_TYPE_AC 1
2497 #define FF_CODER_TYPE_RAW 2
2498 #define FF_CODER_TYPE_RLE 3
2499 #define FF_CODER_TYPE_DEFLATE 4
2502 * - encoding: Set by user.
2503 * - decoding: unused
2509 * - encoding: Set by user.
2510 * - decoding: unused
2515 * minimum Lagrange multipler
2516 * - encoding: Set by user.
2517 * - decoding: unused
2522 * maximum Lagrange multipler
2523 * - encoding: Set by user.
2524 * - decoding: unused
2529 * frame skip threshold
2530 * - encoding: Set by user.
2531 * - decoding: unused
2533 int frame_skip_threshold;
2537 * - encoding: Set by user.
2538 * - decoding: unused
2540 int frame_skip_factor;
2543 * frame skip exponent
2544 * - encoding: Set by user.
2545 * - decoding: unused
2550 * frame skip comparison function
2551 * - encoding: Set by user.
2552 * - decoding: unused
2557 * trellis RD quantization
2558 * - encoding: Set by user.
2559 * - decoding: unused
2564 * - encoding: Set by user.
2565 * - decoding: unused
2567 int min_prediction_order;
2570 * - encoding: Set by user.
2571 * - decoding: unused
2573 int max_prediction_order;
2576 * GOP timecode frame start number
2577 * - encoding: Set by user, in non drop frame format
2578 * - decoding: Set by libavcodec (timecode in the 25 bits format, -1 if unset)
2580 int64_t timecode_frame_start;
2582 /* The RTP callback: This function is called */
2583 /* every time the encoder has a packet to send. */
2584 /* It depends on the encoder if the data starts */
2585 /* with a Start Code (it should). H.263 does. */
2586 /* mb_nb contains the number of macroblocks */
2587 /* encoded in the RTP payload. */
2588 void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2590 int rtp_payload_size; /* The size of the RTP payload: the coder will */
2591 /* do its best to deliver a chunk with size */
2592 /* below rtp_payload_size, the chunk will start */
2593 /* with a start code on some codecs like H.263. */
2594 /* This doesn't take account of any particular */
2595 /* headers inside the transmitted RTP payload. */
2597 /* statistics, used for 2-pass encoding */
2608 * number of bits used for the previously encoded frame
2609 * - encoding: Set by libavcodec.
2610 * - decoding: unused
2615 * pass1 encoding statistics output buffer
2616 * - encoding: Set by libavcodec.
2617 * - decoding: unused
2622 * pass2 encoding statistics input buffer
2623 * Concatenated stuff from stats_out of pass1 should be placed here.
2624 * - encoding: Allocated/set/freed by user.
2625 * - decoding: unused
2630 * Work around bugs in encoders which sometimes cannot be detected automatically.
2631 * - encoding: Set by user
2632 * - decoding: Set by user
2634 int workaround_bugs;
2635 #define FF_BUG_AUTODETECT 1 ///< autodetection
2636 #define FF_BUG_OLD_MSMPEG4 2
2637 #define FF_BUG_XVID_ILACE 4
2638 #define FF_BUG_UMP4 8
2639 #define FF_BUG_NO_PADDING 16
2640 #define FF_BUG_AMV 32
2641 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2642 #define FF_BUG_QPEL_CHROMA 64
2643 #define FF_BUG_STD_QPEL 128
2644 #define FF_BUG_QPEL_CHROMA2 256
2645 #define FF_BUG_DIRECT_BLOCKSIZE 512
2646 #define FF_BUG_EDGE 1024
2647 #define FF_BUG_HPEL_CHROMA 2048
2648 #define FF_BUG_DC_CLIP 4096
2649 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2650 #define FF_BUG_TRUNCATED 16384
2653 * strictly follow the standard (MPEG4, ...).
2654 * - encoding: Set by user.
2655 * - decoding: Set by user.
2656 * Setting this to STRICT or higher means the encoder and decoder will
2657 * generally do stupid things, whereas setting it to unofficial or lower
2658 * will mean the encoder might produce output that is not supported by all
2659 * spec-compliant decoders. Decoders don't differentiate between normal,
2660 * unofficial and experimental (that is, they always try to decode things
2661 * when they can) unless they are explicitly asked to behave stupidly
2662 * (=strictly conform to the specs)
2664 int strict_std_compliance;
2665 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2666 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2667 #define FF_COMPLIANCE_NORMAL 0
2668 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2669 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2672 * error concealment flags
2673 * - encoding: unused
2674 * - decoding: Set by user.
2676 int error_concealment;
2677 #define FF_EC_GUESS_MVS 1
2678 #define FF_EC_DEBLOCK 2
2682 * - encoding: Set by user.
2683 * - decoding: Set by user.
2686 #define FF_DEBUG_PICT_INFO 1
2687 #define FF_DEBUG_RC 2
2688 #define FF_DEBUG_BITSTREAM 4
2689 #define FF_DEBUG_MB_TYPE 8
2690 #define FF_DEBUG_QP 16
2691 #define FF_DEBUG_MV 32
2692 #define FF_DEBUG_DCT_COEFF 0x00000040
2693 #define FF_DEBUG_SKIP 0x00000080
2694 #define FF_DEBUG_STARTCODE 0x00000100
2695 #define FF_DEBUG_PTS 0x00000200
2696 #define FF_DEBUG_ER 0x00000400
2697 #define FF_DEBUG_MMCO 0x00000800
2698 #define FF_DEBUG_BUGS 0x00001000
2699 #define FF_DEBUG_VIS_QP 0x00002000
2700 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2701 #define FF_DEBUG_BUFFERS 0x00008000
2702 #define FF_DEBUG_THREADS 0x00010000
2706 * - encoding: Set by user.
2707 * - decoding: Set by user.
2710 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2711 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2712 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2715 * Error recognition; may misdetect some more or less valid parts as errors.
2716 * - encoding: unused
2717 * - decoding: Set by user.
2719 int err_recognition;
2720 #define AV_EF_CRCCHECK (1<<0)
2721 #define AV_EF_BITSTREAM (1<<1)
2722 #define AV_EF_BUFFER (1<<2)
2723 #define AV_EF_EXPLODE (1<<3)
2725 #define AV_EF_CAREFUL (1<<16)
2726 #define AV_EF_COMPLIANT (1<<17)
2727 #define AV_EF_AGGRESSIVE (1<<18)
2731 * opaque 64bit number (generally a PTS) that will be reordered and
2732 * output in AVFrame.reordered_opaque
2733 * @deprecated in favor of pkt_pts
2734 * - encoding: unused
2735 * - decoding: Set by user.
2737 int64_t reordered_opaque;
2740 * Hardware accelerator in use
2741 * - encoding: unused.
2742 * - decoding: Set by libavcodec
2744 struct AVHWAccel *hwaccel;
2747 * Hardware accelerator context.
2748 * For some hardware accelerators, a global context needs to be
2749 * provided by the user. In that case, this holds display-dependent
2750 * data FFmpeg cannot instantiate itself. Please refer to the
2751 * FFmpeg HW accelerator documentation to know how to fill this
2752 * is. e.g. for VA API, this is a struct vaapi_context.
2753 * - encoding: unused
2754 * - decoding: Set by user
2756 void *hwaccel_context;
2760 * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
2761 * - decoding: unused
2763 uint64_t error[AV_NUM_DATA_POINTERS];
2766 * DCT algorithm, see FF_DCT_* below
2767 * - encoding: Set by user.
2768 * - decoding: unused
2771 #define FF_DCT_AUTO 0
2772 #define FF_DCT_FASTINT 1
2773 #define FF_DCT_INT 2
2774 #define FF_DCT_MMX 3
2775 #define FF_DCT_ALTIVEC 5
2776 #define FF_DCT_FAAN 6
2779 * IDCT algorithm, see FF_IDCT_* below.
2780 * - encoding: Set by user.
2781 * - decoding: Set by user.
2784 #define FF_IDCT_AUTO 0
2785 #define FF_IDCT_INT 1
2786 #define FF_IDCT_SIMPLE 2
2787 #define FF_IDCT_SIMPLEMMX 3
2788 #define FF_IDCT_LIBMPEG2MMX 4
2789 #define FF_IDCT_MMI 5
2790 #define FF_IDCT_ARM 7
2791 #define FF_IDCT_ALTIVEC 8
2792 #define FF_IDCT_SH4 9
2793 #define FF_IDCT_SIMPLEARM 10
2794 #define FF_IDCT_H264 11
2795 #define FF_IDCT_VP3 12
2796 #define FF_IDCT_IPP 13
2797 #define FF_IDCT_XVIDMMX 14
2798 #define FF_IDCT_CAVS 15
2799 #define FF_IDCT_SIMPLEARMV5TE 16
2800 #define FF_IDCT_SIMPLEARMV6 17
2801 #define FF_IDCT_SIMPLEVIS 18
2802 #define FF_IDCT_WMV2 19
2803 #define FF_IDCT_FAAN 20
2804 #define FF_IDCT_EA 21
2805 #define FF_IDCT_SIMPLENEON 22
2806 #define FF_IDCT_SIMPLEALPHA 23
2807 #define FF_IDCT_BINK 24
2812 * @deprecated use av_set_cpu_flags_mask() instead.
2814 attribute_deprecated unsigned dsp_mask;
2818 * bits per sample/pixel from the demuxer (needed for huffyuv).
2819 * - encoding: Set by libavcodec.
2820 * - decoding: Set by user.
2822 int bits_per_coded_sample;
2825 * Bits per sample/pixel of internal libavcodec pixel/sample format.
2826 * - encoding: set by user.
2827 * - decoding: set by libavcodec.
2829 int bits_per_raw_sample;
2832 * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2833 * - encoding: unused
2834 * - decoding: Set by user.
2839 * the picture in the bitstream
2840 * - encoding: Set by libavcodec.
2841 * - decoding: Set by libavcodec.
2843 AVFrame *coded_frame;
2847 * is used to decide how many independent tasks should be passed to execute()
2848 * - encoding: Set by user.
2849 * - decoding: Set by user.
2854 * Which multithreading methods to use.
2855 * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2856 * so clients which cannot provide future frames should not use it.
2858 * - encoding: Set by user, otherwise the default is used.
2859 * - decoding: Set by user, otherwise the default is used.
2862 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2863 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2866 * Which multithreading methods are in use by the codec.
2867 * - encoding: Set by libavcodec.
2868 * - decoding: Set by libavcodec.
2870 int active_thread_type;
2873 * Set by the client if its custom get_buffer() callback can be called
2874 * synchronously from another thread, which allows faster multithreaded decoding.
2875 * draw_horiz_band() will be called from other threads regardless of this setting.
2876 * Ignored if the default get_buffer() is used.
2877 * - encoding: Set by user.
2878 * - decoding: Set by user.
2880 int thread_safe_callbacks;
2883 * The codec may call this to execute several independent things.
2884 * It will return only after finishing all tasks.
2885 * The user may replace this with some multithreaded implementation,
2886 * the default implementation will execute the parts serially.
2887 * @param count the number of things to execute
2888 * - encoding: Set by libavcodec, user can override.
2889 * - decoding: Set by libavcodec, user can override.
2891 int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2894 * The codec may call this to execute several independent things.
2895 * It will return only after finishing all tasks.
2896 * The user may replace this with some multithreaded implementation,
2897 * the default implementation will execute the parts serially.
2898 * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2899 * @param c context passed also to func
2900 * @param count the number of things to execute
2901 * @param arg2 argument passed unchanged to func
2902 * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2903 * @param func function that will be called count times, with jobnr from 0 to count-1.
2904 * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2905 * two instances of func executing at the same time will have the same threadnr.
2906 * @return always 0 currently, but code should handle a future improvement where when any call to func
2907 * returns < 0 no further calls to func may be done and < 0 is returned.
2908 * - encoding: Set by libavcodec, user can override.
2909 * - decoding: Set by libavcodec, user can override.
2911 int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2915 * Can be used by execute() to store some per AVCodecContext stuff.
2916 * - encoding: set by execute()
2917 * - decoding: set by execute()
2919 void *thread_opaque;
2922 * noise vs. sse weight for the nsse comparsion function
2923 * - encoding: Set by user.
2924 * - decoding: unused
2930 * - encoding: Set by user.
2931 * - decoding: Set by libavcodec.
2934 #define FF_PROFILE_UNKNOWN -99
2935 #define FF_PROFILE_RESERVED -100
2937 #define FF_PROFILE_AAC_MAIN 0
2938 #define FF_PROFILE_AAC_LOW 1
2939 #define FF_PROFILE_AAC_SSR 2
2940 #define FF_PROFILE_AAC_LTP 3
2941 #define FF_PROFILE_AAC_HE 4
2942 #define FF_PROFILE_AAC_HE_V2 28
2943 #define FF_PROFILE_AAC_LD 22
2944 #define FF_PROFILE_AAC_ELD 38
2946 #define FF_PROFILE_DTS 20
2947 #define FF_PROFILE_DTS_ES 30
2948 #define FF_PROFILE_DTS_96_24 40
2949 #define FF_PROFILE_DTS_HD_HRA 50
2950 #define FF_PROFILE_DTS_HD_MA 60
2952 #define FF_PROFILE_MPEG2_422 0
2953 #define FF_PROFILE_MPEG2_HIGH 1
2954 #define FF_PROFILE_MPEG2_SS 2
2955 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2956 #define FF_PROFILE_MPEG2_MAIN 4
2957 #define FF_PROFILE_MPEG2_SIMPLE 5
2959 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2960 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2962 #define FF_PROFILE_H264_BASELINE 66
2963 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2964 #define FF_PROFILE_H264_MAIN 77
2965 #define FF_PROFILE_H264_EXTENDED 88
2966 #define FF_PROFILE_H264_HIGH 100
2967 #define FF_PROFILE_H264_HIGH_10 110
2968 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2969 #define FF_PROFILE_H264_HIGH_422 122
2970 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2971 #define FF_PROFILE_H264_HIGH_444 144
2972 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2973 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2974 #define FF_PROFILE_H264_CAVLC_444 44
2976 #define FF_PROFILE_VC1_SIMPLE 0
2977 #define FF_PROFILE_VC1_MAIN 1
2978 #define FF_PROFILE_VC1_COMPLEX 2
2979 #define FF_PROFILE_VC1_ADVANCED 3
2981 #define FF_PROFILE_MPEG4_SIMPLE 0
2982 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2983 #define FF_PROFILE_MPEG4_CORE 2
2984 #define FF_PROFILE_MPEG4_MAIN 3
2985 #define FF_PROFILE_MPEG4_N_BIT 4
2986 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2987 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2988 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2989 #define FF_PROFILE_MPEG4_HYBRID 8
2990 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2991 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2992 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2993 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2994 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2995 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2996 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
3000 * - encoding: Set by user.
3001 * - decoding: Set by libavcodec.
3004 #define FF_LEVEL_UNKNOWN -99
3008 * - encoding: unused
3009 * - decoding: Set by user.
3011 enum AVDiscard skip_loop_filter;
3015 * - encoding: unused
3016 * - decoding: Set by user.
3018 enum AVDiscard skip_idct;
3022 * - encoding: unused
3023 * - decoding: Set by user.
3025 enum AVDiscard skip_frame;
3028 * Header containing style information for text subtitles.
3029 * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3030 * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3031 * the Format line following. It shouldn't include any Dialogue line.
3032 * - encoding: Set/allocated/freed by user (before avcodec_open2())
3033 * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3035 uint8_t *subtitle_header;
3036 int subtitle_header_size;
3039 * Simulates errors in the bitstream to test error concealment.
3040 * - encoding: Set by user.
3041 * - decoding: unused
3046 * Current packet as passed into the decoder, to avoid having
3047 * to pass the packet into every function. Currently only valid
3048 * inside lavc and get/release_buffer callbacks.
3049 * - decoding: set by avcodec_decode_*, read by get_buffer() for setting pkt_pts
3050 * - encoding: unused
3055 * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3056 * Used for compliant TS muxing.
3057 * - encoding: Set by libavcodec.
3058 * - decoding: unused.
3063 * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3064 * Code outside libavcodec should access this field using:
3065 * avcodec_set_pkt_timebase(avctx)
3066 * - encoding unused.
3067 * - decodimg set by user
3069 AVRational pkt_timebase;
3073 * Code outside libavcodec should access this field using:
3074 * avcodec_get_codec_descriptior(avctx)
3075 * - encoding: unused.
3076 * - decoding: set by libavcodec.
3078 const AVCodecDescriptor *codec_descriptor;
3081 * Current statistics for PTS correction.
3082 * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3083 * - encoding: unused
3085 int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3086 int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3087 int64_t pts_correction_last_pts; /// PTS of the last frame
3088 int64_t pts_correction_last_dts; /// DTS of the last frame
3091 AVRational av_codec_get_pkt_timebase (const AVCodecContext *avctx);
3092 void av_codec_set_pkt_timebase (AVCodecContext *avctx, AVRational val);
3094 const AVCodecDescriptor *av_codec_get_codec_descriptor(const AVCodecContext *avctx);
3095 void av_codec_set_codec_descriptor(AVCodecContext *avctx, const AVCodecDescriptor *desc);
3100 typedef struct AVProfile {
3102 const char *name; ///< short name for the profile
3105 typedef struct AVCodecDefault AVCodecDefault;
3112 typedef struct AVCodec {
3114 * Name of the codec implementation.
3115 * The name is globally unique among encoders and among decoders (but an
3116 * encoder and a decoder can share the same name).
3117 * This is the primary way to find a codec from the user perspective.
3121 * Descriptive name for the codec, meant to be more human readable than name.
3122 * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3124 const char *long_name;
3125 enum AVMediaType type;
3128 * Codec capabilities.
3132 const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3133 const enum PixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3134 const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3135 const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3136 const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3137 uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3138 const AVClass *priv_class; ///< AVClass for the private context
3139 const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3141 /*****************************************************************
3142 * No fields below this line are part of the public API. They
3143 * may not be used outside of libavcodec and can be changed and
3145 * New public fields should be added right above.
3146 *****************************************************************
3149 struct AVCodec *next;
3151 * @name Frame-level threading support functions
3155 * If defined, called on thread contexts when they are created.
3156 * If the codec allocates writable tables in init(), re-allocate them here.
3157 * priv_data will be set to a copy of the original.
3159 int (*init_thread_copy)(AVCodecContext *);
3161 * Copy necessary context variables from a previous thread context to the current one.
3162 * If not defined, the next thread will start automatically; otherwise, the codec
3163 * must call ff_thread_finish_setup().
3165 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3167 int (*update_thread_context)(AVCodecContext *dst, const AVCodecContext *src);
3171 * Private codec-specific defaults.
3173 const AVCodecDefault *defaults;
3176 * Initialize codec static data, called from avcodec_register().
3178 void (*init_static_data)(struct AVCodec *codec);
3180 int (*init)(AVCodecContext *);
3181 int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3182 const struct AVSubtitle *sub);
3184 * Encode data to an AVPacket.
3186 * @param avctx codec context
3187 * @param avpkt output AVPacket (may contain a user-provided buffer)
3188 * @param[in] frame AVFrame containing the raw data to be encoded
3189 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3190 * non-empty packet was returned in avpkt.
3191 * @return 0 on success, negative error code on failure
3193 int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3194 int *got_packet_ptr);
3195 int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3196 int (*close)(AVCodecContext *);
3199 * Will be called when seeking
3201 void (*flush)(AVCodecContext *);
3207 typedef struct AVHWAccel {
3209 * Name of the hardware accelerated codec.
3210 * The name is globally unique among encoders and among decoders (but an
3211 * encoder and a decoder can share the same name).
3216 * Type of codec implemented by the hardware accelerator.
3218 * See AVMEDIA_TYPE_xxx
3220 enum AVMediaType type;
3223 * Codec implemented by the hardware accelerator.
3225 * See AV_CODEC_ID_xxx
3230 * Supported pixel format.
3232 * Only hardware accelerated formats are supported here.
3234 enum PixelFormat pix_fmt;
3237 * Hardware accelerated codec capabilities.
3238 * see FF_HWACCEL_CODEC_CAP_*
3242 struct AVHWAccel *next;
3245 * Called at the beginning of each frame or field picture.
3247 * Meaningful frame information (codec specific) is guaranteed to
3248 * be parsed at this point. This function is mandatory.
3250 * Note that buf can be NULL along with buf_size set to 0.
3251 * Otherwise, this means the whole frame is available at this point.
3253 * @param avctx the codec context
3254 * @param buf the frame data buffer base
3255 * @param buf_size the size of the frame in bytes
3256 * @return zero if successful, a negative value otherwise
3258 int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3261 * Callback for each slice.
3263 * Meaningful slice information (codec specific) is guaranteed to
3264 * be parsed at this point. This function is mandatory.
3266 * @param avctx the codec context
3267 * @param buf the slice data buffer base
3268 * @param buf_size the size of the slice in bytes
3269 * @return zero if successful, a negative value otherwise
3271 int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3274 * Called at the end of each frame or field picture.
3276 * The whole picture is parsed at this point and can now be sent
3277 * to the hardware accelerator. This function is mandatory.
3279 * @param avctx the codec context
3280 * @return zero if successful, a negative value otherwise
3282 int (*end_frame)(AVCodecContext *avctx);
3285 * Size of HW accelerator private data.
3287 * Private data is allocated with av_mallocz() before
3288 * AVCodecContext.get_buffer() and deallocated after
3289 * AVCodecContext.release_buffer().
3295 * @defgroup lavc_picture AVPicture
3297 * Functions for working with AVPicture
3302 * four components are given, that's all.
3303 * the last component is alpha
3305 typedef struct AVPicture {
3306 uint8_t *data[AV_NUM_DATA_POINTERS];
3307 int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3314 enum AVSubtitleType {
3317 SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3320 * Plain text, the text field must be set by the decoder and is
3321 * authoritative. ass and pict fields may contain approximations.
3326 * Formatted text, the ass field must be set by the decoder and is
3327 * authoritative. pict and text fields may contain approximations.
3332 typedef struct AVSubtitleRect {
3333 int x; ///< top left corner of pict, undefined when pict is not set
3334 int y; ///< top left corner of pict, undefined when pict is not set
3335 int w; ///< width of pict, undefined when pict is not set
3336 int h; ///< height of pict, undefined when pict is not set
3337 int nb_colors; ///< number of colors in pict, undefined when pict is not set
3340 * data+linesize for the bitmap of this subtitle.
3341 * can be set for text/ass as well once they where rendered
3344 enum AVSubtitleType type;
3346 char *text; ///< 0 terminated plain UTF-8 text
3349 * 0 terminated ASS/SSA compatible event line.
3350 * The presentation of this is unaffected by the other values in this
3356 * 1 indicates this subtitle is a forced subtitle.
3357 * A forced subtitle should be displayed even when subtitles are hidden.
3362 typedef struct AVSubtitle {
3363 uint16_t format; /* 0 = graphics */
3364 uint32_t start_display_time; /* relative to packet pts, in ms */
3365 uint32_t end_display_time; /* relative to packet pts, in ms */
3367 AVSubtitleRect **rects;
3368 int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3372 * If c is NULL, returns the first registered codec,
3373 * if c is non-NULL, returns the next registered codec after c,
3374 * or NULL if c is the last one.
3376 AVCodec *av_codec_next(const AVCodec *c);
3379 * Return the LIBAVCODEC_VERSION_INT constant.
3381 unsigned avcodec_version(void);
3384 * Return the libavcodec build-time configuration.
3386 const char *avcodec_configuration(void);
3389 * Return the libavcodec license.
3391 const char *avcodec_license(void);
3394 * Register the codec codec and initialize libavcodec.
3396 * @warning either this function or avcodec_register_all() must be called
3397 * before any other libavcodec functions.
3399 * @see avcodec_register_all()
3401 void avcodec_register(AVCodec *codec);
3404 * Register all the codecs, parsers and bitstream filters which were enabled at
3405 * configuration time. If you do not call this function you can select exactly
3406 * which formats you want to support, by using the individual registration
3409 * @see avcodec_register
3410 * @see av_register_codec_parser
3411 * @see av_register_bitstream_filter
3413 void avcodec_register_all(void);
3416 #if FF_API_ALLOC_CONTEXT
3418 * Allocate an AVCodecContext and set its fields to default values. The
3419 * resulting struct can be deallocated by simply calling av_free().
3421 * @return An AVCodecContext filled with default values or NULL on failure.
3422 * @see avcodec_get_context_defaults
3424 * @deprecated use avcodec_alloc_context3()
3426 attribute_deprecated
3427 AVCodecContext *avcodec_alloc_context(void);
3429 /** THIS FUNCTION IS NOT YET PART OF THE PUBLIC API!
3430 * we WILL change its arguments and name a few times! */
3431 attribute_deprecated
3432 AVCodecContext *avcodec_alloc_context2(enum AVMediaType);
3435 * Set the fields of the given AVCodecContext to default values.
3437 * @param s The AVCodecContext of which the fields should be set to default values.
3438 * @deprecated use avcodec_get_context_defaults3
3440 attribute_deprecated
3441 void avcodec_get_context_defaults(AVCodecContext *s);
3443 /** THIS FUNCTION IS NOT YET PART OF THE PUBLIC API!
3444 * we WILL change its arguments and name a few times! */
3445 attribute_deprecated
3446 void avcodec_get_context_defaults2(AVCodecContext *s, enum AVMediaType);
3450 * Allocate an AVCodecContext and set its fields to default values. The
3451 * resulting struct can be deallocated by calling avcodec_close() on it followed
3454 * @param codec if non-NULL, allocate private data and initialize defaults
3455 * for the given codec. It is illegal to then call avcodec_open2()
3456 * with a different codec.
3457 * If NULL, then the codec-specific defaults won't be initialized,
3458 * which may result in suboptimal default settings (this is
3459 * important mainly for encoders, e.g. libx264).
3461 * @return An AVCodecContext filled with default values or NULL on failure.
3462 * @see avcodec_get_context_defaults
3464 AVCodecContext *avcodec_alloc_context3(const AVCodec *codec);
3467 * Set the fields of the given AVCodecContext to default values corresponding
3468 * to the given codec (defaults may be codec-dependent).
3470 * Do not call this function if a non-NULL codec has been passed
3471 * to avcodec_alloc_context3() that allocated this AVCodecContext.
3472 * If codec is non-NULL, it is illegal to call avcodec_open2() with a
3473 * different codec on this AVCodecContext.
3475 int avcodec_get_context_defaults3(AVCodecContext *s, const AVCodec *codec);
3478 * Get the AVClass for AVCodecContext. It can be used in combination with
3479 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3481 * @see av_opt_find().
3483 const AVClass *avcodec_get_class(void);
3486 * Get the AVClass for AVFrame. It can be used in combination with
3487 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3489 * @see av_opt_find().
3491 const AVClass *avcodec_get_frame_class(void);
3494 * Get the AVClass for AVSubtitleRect. It can be used in combination with
3495 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3497 * @see av_opt_find().
3499 const AVClass *avcodec_get_subtitle_rect_class(void);
3502 * Copy the settings of the source AVCodecContext into the destination
3503 * AVCodecContext. The resulting destination codec context will be
3504 * unopened, i.e. you are required to call avcodec_open2() before you
3505 * can use this AVCodecContext to decode/encode video/audio data.
3507 * @param dest target codec context, should be initialized with
3508 * avcodec_alloc_context3(), but otherwise uninitialized
3509 * @param src source codec context
3510 * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3512 int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
3515 * Allocate an AVFrame and set its fields to default values. The resulting
3516 * struct must be freed using avcodec_free_frame().
3518 * @return An AVFrame filled with default values or NULL on failure.
3519 * @see avcodec_get_frame_defaults
3521 AVFrame *avcodec_alloc_frame(void);
3524 * Set the fields of the given AVFrame to default values.
3526 * @param frame The AVFrame of which the fields should be set to default values.
3528 void avcodec_get_frame_defaults(AVFrame *frame);
3531 * Free the frame and any dynamically allocated objects in it,
3532 * e.g. extended_data.
3534 * @param frame frame to be freed. The pointer will be set to NULL.
3536 * @warning this function does NOT free the data buffers themselves
3537 * (it does not know how, since they might have been allocated with
3538 * a custom get_buffer()).
3540 void avcodec_free_frame(AVFrame **frame);
3542 #if FF_API_AVCODEC_OPEN
3544 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3545 * function the context has to be allocated.
3547 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3548 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3549 * retrieving a codec.
3551 * @warning This function is not thread safe!
3554 * avcodec_register_all();
3555 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3559 * context = avcodec_alloc_context3(codec);
3561 * if (avcodec_open(context, codec) < 0)
3565 * @param avctx The context which will be set up to use the given codec.
3566 * @param codec The codec to use within the context.
3567 * @return zero on success, a negative value on error
3568 * @see avcodec_alloc_context3, avcodec_find_decoder, avcodec_find_encoder, avcodec_close
3570 * @deprecated use avcodec_open2
3572 attribute_deprecated
3573 int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
3577 * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3578 * function the context has to be allocated with avcodec_alloc_context3().
3580 * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3581 * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3582 * retrieving a codec.
3584 * @warning This function is not thread safe!
3587 * avcodec_register_all();
3588 * av_dict_set(&opts, "b", "2.5M", 0);
3589 * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3593 * context = avcodec_alloc_context3(codec);
3595 * if (avcodec_open2(context, codec, opts) < 0)
3599 * @param avctx The context to initialize.
3600 * @param codec The codec to open this context for. If a non-NULL codec has been
3601 * previously passed to avcodec_alloc_context3() or
3602 * avcodec_get_context_defaults3() for this context, then this
3603 * parameter MUST be either NULL or equal to the previously passed
3605 * @param options A dictionary filled with AVCodecContext and codec-private options.
3606 * On return this object will be filled with options that were not found.
3608 * @return zero on success, a negative value on error
3609 * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3610 * av_dict_set(), av_opt_find().
3612 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3615 * Close a given AVCodecContext and free all the data associated with it
3616 * (but not the AVCodecContext itself).
3618 * Calling this function on an AVCodecContext that hasn't been opened will free
3619 * the codec-specific data allocated in avcodec_alloc_context3() /
3620 * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
3623 int avcodec_close(AVCodecContext *avctx);
3626 * Free all allocated data in the given subtitle struct.
3628 * @param sub AVSubtitle to free.
3630 void avsubtitle_free(AVSubtitle *sub);
3637 * @addtogroup lavc_packet
3642 * Default packet destructor.
3644 void av_destruct_packet(AVPacket *pkt);
3647 * Initialize optional fields of a packet with default values.
3649 * Note, this does not touch the data and size members, which have to be
3650 * initialized separately.
3654 void av_init_packet(AVPacket *pkt);
3657 * Allocate the payload of a packet and initialize its fields with
3661 * @param size wanted payload size
3662 * @return 0 if OK, AVERROR_xxx otherwise
3664 int av_new_packet(AVPacket *pkt, int size);
3667 * Reduce packet size, correctly zeroing padding
3670 * @param size new size
3672 void av_shrink_packet(AVPacket *pkt, int size);
3675 * Increase packet size, correctly zeroing padding
3678 * @param grow_by number of bytes by which to increase the size of the packet
3680 int av_grow_packet(AVPacket *pkt, int grow_by);
3683 * @warning This is a hack - the packet memory allocation stuff is broken. The
3684 * packet is allocated if it was not really allocated.
3686 int av_dup_packet(AVPacket *pkt);
3689 * Copy packet, including contents
3691 * @return 0 on success, negative AVERROR on fail
3693 int av_copy_packet(AVPacket *dst, AVPacket *src);
3698 * @param pkt packet to free
3700 void av_free_packet(AVPacket *pkt);
3703 * Allocate new information of a packet.
3706 * @param type side information type
3707 * @param size side information size
3708 * @return pointer to fresh allocated data or NULL otherwise
3710 uint8_t* av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3714 * Shrink the already allocated side data buffer
3717 * @param type side information type
3718 * @param size new side information size
3719 * @return 0 on success, < 0 on failure
3721 int av_packet_shrink_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3725 * Get side information from packet.
3728 * @param type desired side information type
3729 * @param size pointer for side information size to store (optional)
3730 * @return pointer to data if present or NULL otherwise
3732 uint8_t* av_packet_get_side_data(AVPacket *pkt, enum AVPacketSideDataType type,
3735 int av_packet_merge_side_data(AVPacket *pkt);
3737 int av_packet_split_side_data(AVPacket *pkt);
3745 * @addtogroup lavc_decoding
3750 * Find a registered decoder with a matching codec ID.
3752 * @param id AVCodecID of the requested decoder
3753 * @return A decoder if one was found, NULL otherwise.
3755 AVCodec *avcodec_find_decoder(enum AVCodecID id);
3758 * Find a registered decoder with the specified name.
3760 * @param name name of the requested decoder
3761 * @return A decoder if one was found, NULL otherwise.
3763 AVCodec *avcodec_find_decoder_by_name(const char *name);
3765 int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
3766 void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
3767 int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
3770 * Return the amount of padding in pixels which the get_buffer callback must
3771 * provide around the edge of the image for codecs which do not have the
3772 * CODEC_FLAG_EMU_EDGE flag.
3774 * @return Required padding in pixels.
3776 unsigned avcodec_get_edge_width(void);
3779 * Modify width and height values so that they will result in a memory
3780 * buffer that is acceptable for the codec if you do not use any horizontal
3783 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3784 * If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased
3785 * according to avcodec_get_edge_width() before.
3787 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
3790 * Modify width and height values so that they will result in a memory
3791 * buffer that is acceptable for the codec if you also ensure that all
3792 * line sizes are a multiple of the respective linesize_align[i].
3794 * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3795 * If CODEC_FLAG_EMU_EDGE is not set, the dimensions must have been increased
3796 * according to avcodec_get_edge_width() before.
3798 void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
3799 int linesize_align[AV_NUM_DATA_POINTERS]);
3801 #if FF_API_OLD_DECODE_AUDIO
3803 * Wrapper function which calls avcodec_decode_audio4.
3805 * @deprecated Use avcodec_decode_audio4 instead.
3807 * Decode the audio frame of size avpkt->size from avpkt->data into samples.
3808 * Some decoders may support multiple frames in a single AVPacket, such
3809 * decoders would then just decode the first frame. In this case,
3810 * avcodec_decode_audio3 has to be called again with an AVPacket that contains
3811 * the remaining data in order to decode the second frame etc.
3813 * could be outputted, frame_size_ptr is zero. Otherwise, it is the
3814 * decompressed frame size in bytes.
3816 * @warning You must set frame_size_ptr to the allocated size of the
3817 * output buffer before calling avcodec_decode_audio3().
3819 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3820 * the actual read bytes because some optimized bitstream readers read 32 or 64
3821 * bits at once and could read over the end.
3823 * @warning The end of the input buffer avpkt->data should be set to 0 to ensure that
3824 * no overreading happens for damaged MPEG streams.
3826 * @warning You must not provide a custom get_buffer() when using
3827 * avcodec_decode_audio3(). Doing so will override it with
3828 * avcodec_default_get_buffer. Use avcodec_decode_audio4() instead,
3829 * which does allow the application to provide a custom get_buffer().
3831 * @note You might have to align the input buffer avpkt->data and output buffer
3832 * samples. The alignment requirements depend on the CPU: On some CPUs it isn't
3833 * necessary at all, on others it won't work at all if not aligned and on others
3834 * it will work but it will have an impact on performance.
3836 * In practice, avpkt->data should have 4 byte alignment at minimum and
3837 * samples should be 16 byte aligned unless the CPU doesn't need it
3838 * (AltiVec and SSE do).
3840 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3841 * between input and output, these need to be fed with avpkt->data=NULL,
3842 * avpkt->size=0 at the end to return the remaining frames.
3844 * @param avctx the codec context
3845 * @param[out] samples the output buffer, sample type in avctx->sample_fmt
3846 * If the sample format is planar, each channel plane will
3847 * be the same size, with no padding between channels.
3848 * @param[in,out] frame_size_ptr the output buffer size in bytes
3849 * @param[in] avpkt The input AVPacket containing the input buffer.
3850 * You can create such packet with av_init_packet() and by then setting
3851 * data and size, some decoders might in addition need other fields.
3852 * All decoders are designed to use the least fields possible though.
3853 * @return On error a negative value is returned, otherwise the number of bytes
3854 * used or zero if no frame data was decompressed (used) from the input AVPacket.
3856 attribute_deprecated int avcodec_decode_audio3(AVCodecContext *avctx, int16_t *samples,
3857 int *frame_size_ptr,
3862 * Decode the audio frame of size avpkt->size from avpkt->data into frame.
3864 * Some decoders may support multiple frames in a single AVPacket. Such
3865 * decoders would then just decode the first frame. In this case,
3866 * avcodec_decode_audio4 has to be called again with an AVPacket containing
3867 * the remaining data in order to decode the second frame, etc...
3868 * Even if no frames are returned, the packet needs to be fed to the decoder
3869 * with remaining data until it is completely consumed or an error occurs.
3871 * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
3872 * larger than the actual read bytes because some optimized bitstream
3873 * readers read 32 or 64 bits at once and could read over the end.
3875 * @note You might have to align the input buffer. The alignment requirements
3876 * depend on the CPU and the decoder.
3878 * @param avctx the codec context
3879 * @param[out] frame The AVFrame in which to store decoded audio samples.
3880 * Decoders request a buffer of a particular size by setting
3881 * AVFrame.nb_samples prior to calling get_buffer(). The
3882 * decoder may, however, only utilize part of the buffer by
3883 * setting AVFrame.nb_samples to a smaller value in the
3885 * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
3887 * @param[in] avpkt The input AVPacket containing the input buffer.
3888 * At least avpkt->data and avpkt->size should be set. Some
3889 * decoders might also require additional fields to be set.
3890 * @return A negative error code is returned if an error occurred during
3891 * decoding, otherwise the number of bytes consumed from the input
3892 * AVPacket is returned.
3894 int avcodec_decode_audio4(AVCodecContext *avctx, AVFrame *frame,
3895 int *got_frame_ptr, const AVPacket *avpkt);
3898 * Decode the video frame of size avpkt->size from avpkt->data into picture.
3899 * Some decoders may support multiple frames in a single AVPacket, such
3900 * decoders would then just decode the first frame.
3902 * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3903 * the actual read bytes because some optimized bitstream readers read 32 or 64
3904 * bits at once and could read over the end.
3906 * @warning The end of the input buffer buf should be set to 0 to ensure that
3907 * no overreading happens for damaged MPEG streams.
3909 * @note You might have to align the input buffer avpkt->data.
3910 * The alignment requirements depend on the CPU: on some CPUs it isn't
3911 * necessary at all, on others it won't work at all if not aligned and on others
3912 * it will work but it will have an impact on performance.
3914 * In practice, avpkt->data should have 4 byte alignment at minimum.
3916 * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3917 * between input and output, these need to be fed with avpkt->data=NULL,
3918 * avpkt->size=0 at the end to return the remaining frames.
3920 * @param avctx the codec context
3921 * @param[out] picture The AVFrame in which the decoded video frame will be stored.
3922 * Use avcodec_alloc_frame to get an AVFrame, the codec will
3923 * allocate memory for the actual bitmap.
3924 * with default get/release_buffer(), the decoder frees/reuses the bitmap as it sees fit.
3925 * with overridden get/release_buffer() (needs CODEC_CAP_DR1) the user decides into what buffer the decoder
3926 * decodes and the decoder tells the user once it does not need the data anymore,
3927 * the user app can at this point free/reuse/keep the memory as it sees fit.
3929 * @param[in] avpkt The input AVpacket containing the input buffer.
3930 * You can create such packet with av_init_packet() and by then setting
3931 * data and size, some decoders might in addition need other fields like
3932 * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
3934 * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
3935 * @return On error a negative value is returned, otherwise the number of bytes
3936 * used or zero if no frame could be decompressed.
3938 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
3939 int *got_picture_ptr,
3940 const AVPacket *avpkt);
3943 * Decode a subtitle message.
3944 * Return a negative value on error, otherwise return the number of bytes used.
3945 * If no subtitle could be decompressed, got_sub_ptr is zero.
3946 * Otherwise, the subtitle is stored in *sub.
3947 * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
3948 * simplicity, because the performance difference is expect to be negligible
3949 * and reusing a get_buffer written for video codecs would probably perform badly
3950 * due to a potentially very different allocation pattern.
3952 * @param avctx the codec context
3953 * @param[out] sub The AVSubtitle in which the decoded subtitle will be stored, must be
3954 freed with avsubtitle_free if *got_sub_ptr is set.
3955 * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
3956 * @param[in] avpkt The input AVPacket containing the input buffer.
3958 int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
3963 * @defgroup lavc_parsing Frame parsing
3967 typedef struct AVCodecParserContext {
3969 struct AVCodecParser *parser;
3970 int64_t frame_offset; /* offset of the current frame */
3971 int64_t cur_offset; /* current offset
3972 (incremented by each av_parser_parse()) */
3973 int64_t next_frame_offset; /* offset of the next frame */
3975 int pict_type; /* XXX: Put it back in AVCodecContext. */
3977 * This field is used for proper frame duration computation in lavf.
3978 * It signals, how much longer the frame duration of the current frame
3979 * is compared to normal frame duration.
3981 * frame_duration = (1 + repeat_pict) * time_base
3983 * It is used by codecs like H.264 to display telecined material.
3985 int repeat_pict; /* XXX: Put it back in AVCodecContext. */
3986 int64_t pts; /* pts of the current frame */
3987 int64_t dts; /* dts of the current frame */
3992 int fetch_timestamp;
3994 #define AV_PARSER_PTS_NB 4
3995 int cur_frame_start_index;
3996 int64_t cur_frame_offset[AV_PARSER_PTS_NB];
3997 int64_t cur_frame_pts[AV_PARSER_PTS_NB];
3998 int64_t cur_frame_dts[AV_PARSER_PTS_NB];
4001 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4002 #define PARSER_FLAG_ONCE 0x0002
4003 /// Set if the parser has a valid file offset
4004 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4005 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4007 int64_t offset; ///< byte offset from starting packet start
4008 int64_t cur_frame_end[AV_PARSER_PTS_NB];
4011 * Set by parser to 1 for key frames and 0 for non-key frames.
4012 * It is initialized to -1, so if the parser doesn't set this flag,
4013 * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4019 * Time difference in stream time base units from the pts of this
4020 * packet to the point at which the output from the decoder has converged
4021 * independent from the availability of previous frames. That is, the
4022 * frames are virtually identical no matter if decoding started from
4023 * the very first frame or from this keyframe.
4024 * Is AV_NOPTS_VALUE if unknown.
4025 * This field is not the display duration of the current frame.
4026 * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
4029 * The purpose of this field is to allow seeking in streams that have no
4030 * keyframes in the conventional sense. It corresponds to the
4031 * recovery point SEI in H.264 and match_time_delta in NUT. It is also
4032 * essential for some types of subtitle streams to ensure that all
4033 * subtitles are correctly displayed after seeking.
4035 int64_t convergence_duration;
4037 // Timestamp generation support:
4039 * Synchronization point for start of timestamp generation.
4041 * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4044 * For example, this corresponds to presence of H.264 buffering period
4050 * Offset of the current timestamp against last timestamp sync point in
4051 * units of AVCodecContext.time_base.
4053 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4054 * contain a valid timestamp offset.
4056 * Note that the timestamp of sync point has usually a nonzero
4057 * dts_ref_dts_delta, which refers to the previous sync point. Offset of
4058 * the next frame after timestamp sync point will be usually 1.
4060 * For example, this corresponds to H.264 cpb_removal_delay.
4062 int dts_ref_dts_delta;
4065 * Presentation delay of current frame in units of AVCodecContext.time_base.
4067 * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4068 * contain valid non-negative timestamp delta (presentation time of a frame
4069 * must not lie in the past).
4071 * This delay represents the difference between decoding and presentation
4072 * time of the frame.
4074 * For example, this corresponds to H.264 dpb_output_delay.
4079 * Position of the packet in file.
4081 * Analogous to cur_frame_pts/dts
4083 int64_t cur_frame_pos[AV_PARSER_PTS_NB];
4086 * Byte position of currently parsed frame in stream.
4091 * Previous frame byte position.
4096 * Duration of the current frame.
4097 * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4098 * For all other types, this is in units of AVCodecContext.time_base.
4101 } AVCodecParserContext;
4103 typedef struct AVCodecParser {
4104 int codec_ids[5]; /* several codec IDs are permitted */
4106 int (*parser_init)(AVCodecParserContext *s);
4107 int (*parser_parse)(AVCodecParserContext *s,
4108 AVCodecContext *avctx,
4109 const uint8_t **poutbuf, int *poutbuf_size,
4110 const uint8_t *buf, int buf_size);
4111 void (*parser_close)(AVCodecParserContext *s);
4112 int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
4113 struct AVCodecParser *next;
4116 AVCodecParser *av_parser_next(AVCodecParser *c);
4118 void av_register_codec_parser(AVCodecParser *parser);
4119 AVCodecParserContext *av_parser_init(int codec_id);
4124 * @param s parser context.
4125 * @param avctx codec context.
4126 * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
4127 * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
4128 * @param buf input buffer.
4129 * @param buf_size input length, to signal EOF, this should be 0 (so that the last frame can be output).
4130 * @param pts input presentation timestamp.
4131 * @param dts input decoding timestamp.
4132 * @param pos input byte position in stream.
4133 * @return the number of bytes of the input bitstream used.
4138 * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
4145 * decode_frame(data, size);
4149 int av_parser_parse2(AVCodecParserContext *s,
4150 AVCodecContext *avctx,
4151 uint8_t **poutbuf, int *poutbuf_size,
4152 const uint8_t *buf, int buf_size,
4153 int64_t pts, int64_t dts,
4156 int av_parser_change(AVCodecParserContext *s,
4157 AVCodecContext *avctx,
4158 uint8_t **poutbuf, int *poutbuf_size,
4159 const uint8_t *buf, int buf_size, int keyframe);
4160 void av_parser_close(AVCodecParserContext *s);
4168 * @addtogroup lavc_encoding
4173 * Find a registered encoder with a matching codec ID.
4175 * @param id AVCodecID of the requested encoder
4176 * @return An encoder if one was found, NULL otherwise.
4178 AVCodec *avcodec_find_encoder(enum AVCodecID id);
4181 * Find a registered encoder with the specified name.
4183 * @param name name of the requested encoder
4184 * @return An encoder if one was found, NULL otherwise.
4186 AVCodec *avcodec_find_encoder_by_name(const char *name);
4188 #if FF_API_OLD_ENCODE_AUDIO
4190 * Encode an audio frame from samples into buf.
4192 * @deprecated Use avcodec_encode_audio2 instead.
4194 * @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
4195 * However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
4196 * will know how much space is needed because it depends on the value passed
4197 * in buf_size as described below. In that case a lower value can be used.
4199 * @param avctx the codec context
4200 * @param[out] buf the output buffer
4201 * @param[in] buf_size the output buffer size
4202 * @param[in] samples the input buffer containing the samples
4203 * The number of samples read from this buffer is frame_size*channels,
4204 * both of which are defined in avctx.
4205 * For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
4206 * samples read from samples is equal to:
4207 * buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
4208 * This also implies that av_get_bits_per_sample() must not return 0 for these
4210 * @return On error a negative value is returned, on success zero or the number
4211 * of bytes used to encode the data read from the input buffer.
4213 int attribute_deprecated avcodec_encode_audio(AVCodecContext *avctx,
4214 uint8_t *buf, int buf_size,
4215 const short *samples);
4219 * Encode a frame of audio.
4221 * Takes input samples from frame and writes the next output packet, if
4222 * available, to avpkt. The output packet does not necessarily contain data for
4223 * the most recent frame, as encoders can delay, split, and combine input frames
4224 * internally as needed.
4226 * @param avctx codec context
4227 * @param avpkt output AVPacket.
4228 * The user can supply an output buffer by setting
4229 * avpkt->data and avpkt->size prior to calling the
4230 * function, but if the size of the user-provided data is not
4231 * large enough, encoding will fail. If avpkt->data and
4232 * avpkt->size are set, avpkt->destruct must also be set. All
4233 * other AVPacket fields will be reset by the encoder using
4234 * av_init_packet(). If avpkt->data is NULL, the encoder will
4235 * allocate it. The encoder will set avpkt->size to the size
4236 * of the output packet.
4238 * If this function fails or produces no output, avpkt will be
4239 * freed using av_free_packet() (i.e. avpkt->destruct will be
4240 * called to free the user supplied buffer).
4241 * @param[in] frame AVFrame containing the raw audio data to be encoded.
4242 * May be NULL when flushing an encoder that has the
4243 * CODEC_CAP_DELAY capability set.
4244 * If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4245 * can have any number of samples.
4246 * If it is not set, frame->nb_samples must be equal to
4247 * avctx->frame_size for all frames except the last.
4248 * The final frame may be smaller than avctx->frame_size.
4249 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4250 * output packet is non-empty, and to 0 if it is
4251 * empty. If the function returns an error, the
4252 * packet can be assumed to be invalid, and the
4253 * value of got_packet_ptr is undefined and should
4255 * @return 0 on success, negative error code on failure
4257 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
4258 const AVFrame *frame, int *got_packet_ptr);
4260 #if FF_API_OLD_ENCODE_VIDEO
4262 * @deprecated use avcodec_encode_video2() instead.
4264 * Encode a video frame from pict into buf.
4265 * The input picture should be
4266 * stored using a specific format, namely avctx.pix_fmt.
4268 * @param avctx the codec context
4269 * @param[out] buf the output buffer for the bitstream of encoded frame
4270 * @param[in] buf_size the size of the output buffer in bytes
4271 * @param[in] pict the input picture to encode
4272 * @return On error a negative value is returned, on success zero or the number
4273 * of bytes used from the output buffer.
4275 attribute_deprecated
4276 int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4277 const AVFrame *pict);
4281 * Encode a frame of video.
4283 * Takes input raw video data from frame and writes the next output packet, if
4284 * available, to avpkt. The output packet does not necessarily contain data for
4285 * the most recent frame, as encoders can delay and reorder input frames
4286 * internally as needed.
4288 * @param avctx codec context
4289 * @param avpkt output AVPacket.
4290 * The user can supply an output buffer by setting
4291 * avpkt->data and avpkt->size prior to calling the
4292 * function, but if the size of the user-provided data is not
4293 * large enough, encoding will fail. All other AVPacket fields
4294 * will be reset by the encoder using av_init_packet(). If
4295 * avpkt->data is NULL, the encoder will allocate it.
4296 * The encoder will set avpkt->size to the size of the
4297 * output packet. The returned data (if any) belongs to the
4298 * caller, he is responsible for freeing it.
4300 * If this function fails or produces no output, avpkt will be
4301 * freed using av_free_packet() (i.e. avpkt->destruct will be
4302 * called to free the user supplied buffer).
4303 * @param[in] frame AVFrame containing the raw video data to be encoded.
4304 * May be NULL when flushing an encoder that has the
4305 * CODEC_CAP_DELAY capability set.
4306 * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4307 * output packet is non-empty, and to 0 if it is
4308 * empty. If the function returns an error, the
4309 * packet can be assumed to be invalid, and the
4310 * value of got_packet_ptr is undefined and should
4312 * @return 0 on success, negative error code on failure
4314 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
4315 const AVFrame *frame, int *got_packet_ptr);
4317 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4318 const AVSubtitle *sub);
4326 * @defgroup lavc_resample Audio resampling
4331 struct ReSampleContext;
4332 struct AVResampleContext;
4334 typedef struct ReSampleContext ReSampleContext;
4337 * Initialize audio resampling context.
4339 * @param output_channels number of output channels
4340 * @param input_channels number of input channels
4341 * @param output_rate output sample rate
4342 * @param input_rate input sample rate
4343 * @param sample_fmt_out requested output sample format
4344 * @param sample_fmt_in input sample format
4345 * @param filter_length length of each FIR filter in the filterbank relative to the cutoff frequency
4346 * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4347 * @param linear if 1 then the used FIR filter will be linearly interpolated
4348 between the 2 closest, if 0 the closest will be used
4349 * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4350 * @return allocated ReSampleContext, NULL if error occurred
4352 ReSampleContext *av_audio_resample_init(int output_channels, int input_channels,
4353 int output_rate, int input_rate,
4354 enum AVSampleFormat sample_fmt_out,
4355 enum AVSampleFormat sample_fmt_in,
4356 int filter_length, int log2_phase_count,
4357 int linear, double cutoff);
4359 int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
4362 * Free resample context.
4364 * @param s a non-NULL pointer to a resample context previously
4365 * created with av_audio_resample_init()
4367 void audio_resample_close(ReSampleContext *s);
4371 * Initialize an audio resampler.
4372 * Note, if either rate is not an integer then simply scale both rates up so they are.
4373 * @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
4374 * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4375 * @param linear If 1 then the used FIR filter will be linearly interpolated
4376 between the 2 closest, if 0 the closest will be used
4377 * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4379 struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff);
4382 * Resample an array of samples using a previously configured context.
4383 * @param src an array of unconsumed samples
4384 * @param consumed the number of samples of src which have been consumed are returned here
4385 * @param src_size the number of unconsumed samples available
4386 * @param dst_size the amount of space in samples available in dst
4387 * @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.
4388 * @return the number of samples written in dst or -1 if an error occurred
4390 int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx);
4394 * Compensate samplerate/timestamp drift. The compensation is done by changing
4395 * the resampler parameters, so no audible clicks or similar distortions occur
4396 * @param compensation_distance distance in output samples over which the compensation should be performed
4397 * @param sample_delta number of output samples which should be output less
4399 * example: av_resample_compensate(c, 10, 500)
4400 * here instead of 510 samples only 500 samples would be output
4402 * note, due to rounding the actual compensation might be slightly different,
4403 * especially if the compensation_distance is large and the in_rate used during init is small
4405 void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance);
4406 void av_resample_close(struct AVResampleContext *c);
4413 * @addtogroup lavc_picture
4418 * Allocate memory for a picture. Call avpicture_free() to free it.
4420 * @see avpicture_fill()
4422 * @param picture the picture to be filled in
4423 * @param pix_fmt the format of the picture
4424 * @param width the width of the picture
4425 * @param height the height of the picture
4426 * @return zero if successful, a negative value if not
4428 int avpicture_alloc(AVPicture *picture, enum PixelFormat pix_fmt, int width, int height);
4431 * Free a picture previously allocated by avpicture_alloc().
4432 * The data buffer used by the AVPicture is freed, but the AVPicture structure
4435 * @param picture the AVPicture to be freed
4437 void avpicture_free(AVPicture *picture);
4440 * Fill in the AVPicture fields, always assume a linesize alignment of
4443 * @see av_image_fill_arrays()
4445 int avpicture_fill(AVPicture *picture, uint8_t *ptr,
4446 enum PixelFormat pix_fmt, int width, int height);
4449 * Copy pixel data from an AVPicture into a buffer, always assume a
4450 * linesize alignment of 1.
4452 * @see av_image_copy_to_buffer()
4454 int avpicture_layout(const AVPicture* src, enum PixelFormat pix_fmt, int width, int height,
4455 unsigned char *dest, int dest_size);
4458 * Calculate the size in bytes that a picture of the given width and height
4459 * would occupy if stored in the given picture format.
4460 * Always assume a linesize alignment of 1.
4462 * @see av_image_get_buffer_size().
4464 int avpicture_get_size(enum PixelFormat pix_fmt, int width, int height);
4467 * deinterlace - if not supported return -1
4469 int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
4470 enum PixelFormat pix_fmt, int width, int height);
4472 * Copy image src to dst. Wraps av_image_copy().
4474 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4475 enum PixelFormat pix_fmt, int width, int height);
4478 * Crop image top and left side.
4480 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4481 enum PixelFormat pix_fmt, int top_band, int left_band);
4486 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum PixelFormat pix_fmt,
4487 int padtop, int padbottom, int padleft, int padright, int *color);
4494 * @defgroup lavc_misc Utility functions
4497 * Miscellaneous utility functions related to both encoding and decoding
4503 * @defgroup lavc_misc_pixfmt Pixel formats
4505 * Functions for working with pixel formats.
4509 void avcodec_get_chroma_sub_sample(enum PixelFormat pix_fmt, int *h_shift, int *v_shift);
4512 * Return a value representing the fourCC code associated to the
4513 * pixel format pix_fmt, or 0 if no associated fourCC code can be
4516 unsigned int avcodec_pix_fmt_to_codec_tag(enum PixelFormat pix_fmt);
4518 #define FF_LOSS_RESOLUTION 0x0001 /**< loss due to resolution change */
4519 #define FF_LOSS_DEPTH 0x0002 /**< loss due to color depth change */
4520 #define FF_LOSS_COLORSPACE 0x0004 /**< loss due to color space conversion */
4521 #define FF_LOSS_ALPHA 0x0008 /**< loss of alpha bits */
4522 #define FF_LOSS_COLORQUANT 0x0010 /**< loss due to color quantization */
4523 #define FF_LOSS_CHROMA 0x0020 /**< loss of chroma (e.g. RGB to gray conversion) */
4526 * Compute what kind of losses will occur when converting from one specific
4527 * pixel format to another.
4528 * When converting from one pixel format to another, information loss may occur.
4529 * For example, when converting from RGB24 to GRAY, the color information will
4530 * be lost. Similarly, other losses occur when converting from some formats to
4531 * other formats. These losses can involve loss of chroma, but also loss of
4532 * resolution, loss of color depth, loss due to the color space conversion, loss
4533 * of the alpha bits or loss due to color quantization.
4534 * avcodec_get_fix_fmt_loss() informs you about the various types of losses
4535 * which will occur when converting from one pixel format to another.
4537 * @param[in] dst_pix_fmt destination pixel format
4538 * @param[in] src_pix_fmt source pixel format
4539 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4540 * @return Combination of flags informing you what kind of losses will occur
4541 * (maximum loss for an invalid dst_pix_fmt).
4543 int avcodec_get_pix_fmt_loss(enum PixelFormat dst_pix_fmt, enum PixelFormat src_pix_fmt,
4546 #if FF_API_FIND_BEST_PIX_FMT
4548 * @deprecated use avcodec_find_best_pix_fmt_of_2() instead.
4550 * Find the best pixel format to convert to given a certain source pixel
4551 * format. When converting from one pixel format to another, information loss
4552 * may occur. For example, when converting from RGB24 to GRAY, the color
4553 * information will be lost. Similarly, other losses occur when converting from
4554 * some formats to other formats. avcodec_find_best_pix_fmt() searches which of
4555 * the given pixel formats should be used to suffer the least amount of loss.
4556 * The pixel formats from which it chooses one, are determined by the
4557 * pix_fmt_mask parameter.
4559 * Note, only the first 64 pixel formats will fit in pix_fmt_mask.
4562 * src_pix_fmt = PIX_FMT_YUV420P;
4563 * pix_fmt_mask = (1 << PIX_FMT_YUV422P) | (1 << PIX_FMT_RGB24);
4564 * dst_pix_fmt = avcodec_find_best_pix_fmt(pix_fmt_mask, src_pix_fmt, alpha, &loss);
4567 * @param[in] pix_fmt_mask bitmask determining which pixel format to choose from
4568 * @param[in] src_pix_fmt source pixel format
4569 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4570 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4571 * @return The best pixel format to convert to or -1 if none was found.
4573 attribute_deprecated
4574 enum PixelFormat avcodec_find_best_pix_fmt(int64_t pix_fmt_mask, enum PixelFormat src_pix_fmt,
4575 int has_alpha, int *loss_ptr);
4576 #endif /* FF_API_FIND_BEST_PIX_FMT */
4579 * Find the best pixel format to convert to given a certain source pixel
4580 * format. When converting from one pixel format to another, information loss
4581 * may occur. For example, when converting from RGB24 to GRAY, the color
4582 * information will be lost. Similarly, other losses occur when converting from
4583 * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
4584 * the given pixel formats should be used to suffer the least amount of loss.
4585 * The pixel formats from which it chooses one, are determined by the
4586 * pix_fmt_list parameter.
4589 * @param[in] pix_fmt_list PIX_FMT_NONE terminated array of pixel formats to choose from
4590 * @param[in] src_pix_fmt source pixel format
4591 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4592 * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4593 * @return The best pixel format to convert to or -1 if none was found.
4595 enum PixelFormat avcodec_find_best_pix_fmt_of_list(enum PixelFormat *pix_fmt_list,
4596 enum PixelFormat src_pix_fmt,
4597 int has_alpha, int *loss_ptr);
4600 * Find the best pixel format to convert to given a certain source pixel
4601 * format and a selection of two destination pixel formats. When converting from
4602 * one pixel format to another, information loss may occur. For example, when converting
4603 * from RGB24 to GRAY, the color information will be lost. Similarly, other losses occur when
4604 * converting from some formats to other formats. avcodec_find_best_pix_fmt_of_2() selects which of
4605 * the given pixel formats should be used to suffer the least amount of loss.
4607 * If one of the destination formats is PIX_FMT_NONE the other pixel format (if valid) will be
4611 * src_pix_fmt = PIX_FMT_YUV420P;
4612 * dst_pix_fmt1= PIX_FMT_RGB24;
4613 * dst_pix_fmt2= PIX_FMT_GRAY8;
4614 * dst_pix_fmt3= PIX_FMT_RGB8;
4615 * loss= FF_LOSS_CHROMA; // don't care about chroma loss, so chroma loss will be ignored.
4616 * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt1, dst_pix_fmt2, src_pix_fmt, alpha, &loss);
4617 * dst_pix_fmt = avcodec_find_best_pix_fmt_of_2(dst_pix_fmt, dst_pix_fmt3, src_pix_fmt, alpha, &loss);
4620 * @param[in] dst_pix_fmt1 One of the two destination pixel formats to choose from
4621 * @param[in] dst_pix_fmt2 The other of the two destination pixel formats to choose from
4622 * @param[in] src_pix_fmt Source pixel format
4623 * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4624 * @param[in, out] loss_ptr Combination of loss flags. In: selects which of the losses to ignore, i.e.
4625 * NULL or value of zero means we care about all losses. Out: the loss
4626 * that occurs when converting from src to selected dst pixel format.
4627 * @return The best pixel format to convert to or -1 if none was found.
4629 enum PixelFormat avcodec_find_best_pix_fmt_of_2(enum PixelFormat dst_pix_fmt1, enum PixelFormat dst_pix_fmt2,
4630 enum PixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4632 attribute_deprecated
4633 #if AV_HAVE_INCOMPATIBLE_FORK_ABI
4634 enum PixelFormat avcodec_find_best_pix_fmt2(enum PixelFormat *pix_fmt_list,
4635 enum PixelFormat src_pix_fmt,
4636 int has_alpha, int *loss_ptr);
4638 enum PixelFormat avcodec_find_best_pix_fmt2(enum PixelFormat dst_pix_fmt1, enum PixelFormat dst_pix_fmt2,
4639 enum PixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4643 enum PixelFormat avcodec_default_get_format(struct AVCodecContext *s, const enum PixelFormat * fmt);
4649 void avcodec_set_dimensions(AVCodecContext *s, int width, int height);
4652 * Put a string representing the codec tag codec_tag in buf.
4654 * @param buf_size size in bytes of buf
4655 * @return the length of the string that would have been generated if
4656 * enough space had been available, excluding the trailing null
4658 size_t av_get_codec_tag_string(char *buf, size_t buf_size, unsigned int codec_tag);
4660 void avcodec_string(char *buf, int buf_size, AVCodecContext *enc, int encode);
4663 * Return a name for the specified profile, if available.
4665 * @param codec the codec that is searched for the given profile
4666 * @param profile the profile value for which a name is requested
4667 * @return A name for the profile if found, NULL otherwise.
4669 const char *av_get_profile_name(const AVCodec *codec, int profile);
4671 int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2),void *arg, int *ret, int count, int size);
4672 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
4673 //FIXME func typedef
4676 * Fill audio frame data and linesize.
4677 * AVFrame extended_data channel pointers are allocated if necessary for
4680 * @param frame the AVFrame
4681 * frame->nb_samples must be set prior to calling the
4682 * function. This function fills in frame->data,
4683 * frame->extended_data, frame->linesize[0].
4684 * @param nb_channels channel count
4685 * @param sample_fmt sample format
4686 * @param buf buffer to use for frame data
4687 * @param buf_size size of buffer
4688 * @param align plane size sample alignment (0 = default)
4689 * @return 0 on success, negative error code on failure
4691 int avcodec_fill_audio_frame(AVFrame *frame, int nb_channels,
4692 enum AVSampleFormat sample_fmt, const uint8_t *buf,
4693 int buf_size, int align);
4696 * Flush buffers, should be called when seeking or when switching to a different stream.
4698 void avcodec_flush_buffers(AVCodecContext *avctx);
4700 void avcodec_default_free_buffers(AVCodecContext *s);
4703 * Return codec bits per sample.
4705 * @param[in] codec_id the codec
4706 * @return Number of bits per sample or zero if unknown for the given codec.
4708 int av_get_bits_per_sample(enum AVCodecID codec_id);
4711 * Return the PCM codec associated with a sample format.
4712 * @param be endianness, 0 for little, 1 for big,
4713 * -1 (or anything else) for native
4714 * @return AV_CODEC_ID_PCM_* or AV_CODEC_ID_NONE
4716 enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be);
4719 * Return codec bits per sample.
4720 * Only return non-zero if the bits per sample is exactly correct, not an
4723 * @param[in] codec_id the codec
4724 * @return Number of bits per sample or zero if unknown for the given codec.
4726 int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
4729 * Return audio frame duration.
4731 * @param avctx codec context
4732 * @param frame_bytes size of the frame, or 0 if unknown
4733 * @return frame duration, in samples, if known. 0 if not able to
4736 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
4739 typedef struct AVBitStreamFilterContext {
4741 struct AVBitStreamFilter *filter;
4742 AVCodecParserContext *parser;
4743 struct AVBitStreamFilterContext *next;
4744 } AVBitStreamFilterContext;
4747 typedef struct AVBitStreamFilter {
4750 int (*filter)(AVBitStreamFilterContext *bsfc,
4751 AVCodecContext *avctx, const char *args,
4752 uint8_t **poutbuf, int *poutbuf_size,
4753 const uint8_t *buf, int buf_size, int keyframe);
4754 void (*close)(AVBitStreamFilterContext *bsfc);
4755 struct AVBitStreamFilter *next;
4756 } AVBitStreamFilter;
4758 void av_register_bitstream_filter(AVBitStreamFilter *bsf);
4759 AVBitStreamFilterContext *av_bitstream_filter_init(const char *name);
4760 int av_bitstream_filter_filter(AVBitStreamFilterContext *bsfc,
4761 AVCodecContext *avctx, const char *args,
4762 uint8_t **poutbuf, int *poutbuf_size,
4763 const uint8_t *buf, int buf_size, int keyframe);
4764 void av_bitstream_filter_close(AVBitStreamFilterContext *bsf);
4766 AVBitStreamFilter *av_bitstream_filter_next(AVBitStreamFilter *f);
4771 * Reallocate the given block if it is not large enough, otherwise do nothing.
4775 void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size);
4778 * Allocate a buffer, reusing the given one if large enough.
4780 * Contrary to av_fast_realloc the current buffer contents might not be
4781 * preserved and on error the old buffer is freed, thus no special
4782 * handling to avoid memleaks is necessary.
4784 * @param ptr pointer to pointer to already allocated buffer, overwritten with pointer to new buffer
4785 * @param size size of the buffer *ptr points to
4786 * @param min_size minimum size of *ptr buffer after returning, *ptr will be NULL and
4787 * *size 0 if an error occurred.
4789 void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size);
4792 * Same behaviour av_fast_malloc but the buffer has additional
4793 * FF_INPUT_PADDING_SIZE at the end which will will always be 0.
4795 * In addition the whole buffer will initially and after resizes
4796 * be 0-initialized so that no uninitialized data will ever appear.
4798 void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size);
4801 * Same behaviour av_fast_padded_malloc except that buffer will always
4802 * be 0-initialized after call.
4804 void av_fast_padded_mallocz(void *ptr, unsigned int *size, size_t min_size);
4807 * Encode extradata length to a buffer. Used by xiph codecs.
4809 * @param s buffer to write to; must be at least (v/255+1) bytes long
4810 * @param v size of extradata in bytes
4811 * @return number of bytes written to the buffer.
4813 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
4816 * Log a generic warning message about a missing feature. This function is
4817 * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
4818 * only, and would normally not be used by applications.
4819 * @param[in] avc a pointer to an arbitrary struct of which the first field is
4820 * a pointer to an AVClass struct
4821 * @param[in] feature string containing the name of the missing feature
4822 * @param[in] want_sample indicates if samples are wanted which exhibit this feature.
4823 * If want_sample is non-zero, additional verbage will be added to the log
4824 * message which tells the user how to report samples to the development
4827 void av_log_missing_feature(void *avc, const char *feature, int want_sample);
4830 * Log a generic warning message asking for a sample. This function is
4831 * intended to be used internally by FFmpeg (libavcodec, libavformat, etc.)
4832 * only, and would normally not be used by applications.
4833 * @param[in] avc a pointer to an arbitrary struct of which the first field is
4834 * a pointer to an AVClass struct
4835 * @param[in] msg string containing an optional message, or NULL if no message
4837 void av_log_ask_for_sample(void *avc, const char *msg, ...) av_printf_format(2, 3);
4840 * Register the hardware accelerator hwaccel.
4842 void av_register_hwaccel(AVHWAccel *hwaccel);
4845 * If hwaccel is NULL, returns the first registered hardware accelerator,
4846 * if hwaccel is non-NULL, returns the next registered hardware accelerator
4847 * after hwaccel, or NULL if hwaccel is the last one.
4849 AVHWAccel *av_hwaccel_next(AVHWAccel *hwaccel);
4853 * Lock operation used by lockmgr
4856 AV_LOCK_CREATE, ///< Create a mutex
4857 AV_LOCK_OBTAIN, ///< Lock the mutex
4858 AV_LOCK_RELEASE, ///< Unlock the mutex
4859 AV_LOCK_DESTROY, ///< Free mutex resources
4863 * Register a user provided lock manager supporting the operations
4864 * specified by AVLockOp. mutex points to a (void *) where the
4865 * lockmgr should store/get a pointer to a user allocated mutex. It's
4866 * NULL upon AV_LOCK_CREATE and != NULL for all other ops.
4868 * @param cb User defined callback. Note: FFmpeg may invoke calls to this
4869 * callback during the call to av_lockmgr_register().
4870 * Thus, the application must be prepared to handle that.
4871 * If cb is set to NULL the lockmgr will be unregistered.
4872 * Also note that during unregistration the previously registered
4873 * lockmgr callback may also be invoked.
4875 int av_lockmgr_register(int (*cb)(void **mutex, enum AVLockOp op));
4878 * Get the type of the given codec.
4880 enum AVMediaType avcodec_get_type(enum AVCodecID codec_id);
4883 * Get the name of a codec.
4884 * @return a static string identifying the codec; never NULL
4886 const char *avcodec_get_name(enum AVCodecID id);
4889 * @return a positive value if s is open (i.e. avcodec_open2() was called on it
4890 * with no corresponding avcodec_close()), 0 otherwise.
4892 int avcodec_is_open(AVCodecContext *s);
4895 * @return a non-zero number if codec is an encoder, zero otherwise
4897 int av_codec_is_encoder(const AVCodec *codec);
4900 * @return a non-zero number if codec is a decoder, zero otherwise
4902 int av_codec_is_decoder(const AVCodec *codec);
4905 * @return descriptor for given codec ID or NULL if no descriptor exists.
4907 const AVCodecDescriptor *avcodec_descriptor_get(enum AVCodecID id);
4910 * Iterate over all codec descriptors known to libavcodec.
4912 * @param prev previous descriptor. NULL to get the first descriptor.
4914 * @return next descriptor or NULL after the last descriptor
4916 const AVCodecDescriptor *avcodec_descriptor_next(const AVCodecDescriptor *prev);
4919 * @return codec descriptor with the given name or NULL if no such descriptor
4922 const AVCodecDescriptor *avcodec_descriptor_get_by_name(const char *name);
4928 #endif /* AVCODEC_AVCODEC_H */