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avcodec.h
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1 /*
2  * copyright (c) 2001 Fabrice Bellard
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef AVCODEC_AVCODEC_H
22 #define AVCODEC_AVCODEC_H
23 
24 /**
25  * @file
26  * @ingroup libavc
27  * Libavcodec external API header
28  */
29 
30 #include <errno.h>
31 #include "libavutil/samplefmt.h"
32 #include "libavutil/attributes.h"
33 #include "libavutil/avutil.h"
34 #include "libavutil/buffer.h"
35 #include "libavutil/cpu.h"
37 #include "libavutil/dict.h"
38 #include "libavutil/frame.h"
39 #include "libavutil/log.h"
40 #include "libavutil/pixfmt.h"
41 #include "libavutil/rational.h"
42 
43 #include "version.h"
44 
45 #if FF_API_FAST_MALLOC
46 // to provide fast_*alloc
47 #include "libavutil/mem.h"
48 #endif
49 
50 /**
51  * @defgroup libavc Encoding/Decoding Library
52  * @{
53  *
54  * @defgroup lavc_decoding Decoding
55  * @{
56  * @}
57  *
58  * @defgroup lavc_encoding Encoding
59  * @{
60  * @}
61  *
62  * @defgroup lavc_codec Codecs
63  * @{
64  * @defgroup lavc_codec_native Native Codecs
65  * @{
66  * @}
67  * @defgroup lavc_codec_wrappers External library wrappers
68  * @{
69  * @}
70  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
71  * @{
72  * @}
73  * @}
74  * @defgroup lavc_internal Internal
75  * @{
76  * @}
77  * @}
78  *
79  */
80 
81 /**
82  * @defgroup lavc_core Core functions/structures.
83  * @ingroup libavc
84  *
85  * Basic definitions, functions for querying libavcodec capabilities,
86  * allocating core structures, etc.
87  * @{
88  */
89 
90 
91 /**
92  * Identify the syntax and semantics of the bitstream.
93  * The principle is roughly:
94  * Two decoders with the same ID can decode the same streams.
95  * Two encoders with the same ID can encode compatible streams.
96  * There may be slight deviations from the principle due to implementation
97  * details.
98  *
99  * If you add a codec ID to this list, add it so that
100  * 1. no value of a existing codec ID changes (that would break ABI),
101  * 2. Give it a value which when taken as ASCII is recognized uniquely by a human as this specific codec.
102  * This ensures that 2 forks can independently add AVCodecIDs without producing conflicts.
103  *
104  * After adding new codec IDs, do not forget to add an entry to the codec
105  * descriptor list and bump libavcodec minor version.
106  */
107 enum AVCodecID {
109 
110  /* video codecs */
112  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
113 #if FF_API_XVMC
114  AV_CODEC_ID_MPEG2VIDEO_XVMC,
115 #endif /* FF_API_XVMC */
298 
299  AV_CODEC_ID_BRENDER_PIX= MKBETAG('B','P','I','X'),
300  AV_CODEC_ID_Y41P = MKBETAG('Y','4','1','P'),
301  AV_CODEC_ID_ESCAPE130 = MKBETAG('E','1','3','0'),
302  AV_CODEC_ID_EXR = MKBETAG('0','E','X','R'),
303  AV_CODEC_ID_AVRP = MKBETAG('A','V','R','P'),
304 
305  AV_CODEC_ID_012V = MKBETAG('0','1','2','V'),
306  AV_CODEC_ID_G2M = MKBETAG( 0 ,'G','2','M'),
307  AV_CODEC_ID_AVUI = MKBETAG('A','V','U','I'),
308  AV_CODEC_ID_AYUV = MKBETAG('A','Y','U','V'),
309  AV_CODEC_ID_TARGA_Y216 = MKBETAG('T','2','1','6'),
310  AV_CODEC_ID_V308 = MKBETAG('V','3','0','8'),
311  AV_CODEC_ID_V408 = MKBETAG('V','4','0','8'),
312  AV_CODEC_ID_YUV4 = MKBETAG('Y','U','V','4'),
313  AV_CODEC_ID_SANM = MKBETAG('S','A','N','M'),
314  AV_CODEC_ID_PAF_VIDEO = MKBETAG('P','A','F','V'),
315  AV_CODEC_ID_AVRN = MKBETAG('A','V','R','n'),
316  AV_CODEC_ID_CPIA = MKBETAG('C','P','I','A'),
317  AV_CODEC_ID_XFACE = MKBETAG('X','F','A','C'),
318  AV_CODEC_ID_SGIRLE = MKBETAG('S','G','I','R'),
319  AV_CODEC_ID_MVC1 = MKBETAG('M','V','C','1'),
320  AV_CODEC_ID_MVC2 = MKBETAG('M','V','C','2'),
321  AV_CODEC_ID_SNOW = MKBETAG('S','N','O','W'),
322  AV_CODEC_ID_WEBP = MKBETAG('W','E','B','P'),
323  AV_CODEC_ID_SMVJPEG = MKBETAG('S','M','V','J'),
324  AV_CODEC_ID_HEVC = MKBETAG('H','2','6','5'),
325 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
326  AV_CODEC_ID_VP7 = MKBETAG('V','P','7','0'),
327 
328  /* various PCM "codecs" */
329  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
363 
364  /* various ADPCM codecs */
396  AV_CODEC_ID_ADPCM_VIMA = MKBETAG('V','I','M','A'),
397  AV_CODEC_ID_VIMA = MKBETAG('V','I','M','A'),
398  AV_CODEC_ID_ADPCM_AFC = MKBETAG('A','F','C',' '),
399  AV_CODEC_ID_ADPCM_IMA_OKI = MKBETAG('O','K','I',' '),
400  AV_CODEC_ID_ADPCM_DTK = MKBETAG('D','T','K',' '),
401  AV_CODEC_ID_ADPCM_IMA_RAD = MKBETAG('R','A','D',' '),
402  AV_CODEC_ID_ADPCM_G726LE = MKBETAG('6','2','7','G'),
403 
404  /* AMR */
407 
408  /* RealAudio codecs*/
411 
412  /* various DPCM codecs */
417 
418  /* audio codecs */
419  AV_CODEC_ID_MP2 = 0x15000,
420  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
437  AV_CODEC_ID_GSM, ///< as in Berlin toast format
449  AV_CODEC_ID_GSM_MS, /* as found in WAV */
451 #if FF_API_VOXWARE
453 #endif
488  AV_CODEC_ID_FFWAVESYNTH = MKBETAG('F','F','W','S'),
489  AV_CODEC_ID_SONIC = MKBETAG('S','O','N','C'),
490  AV_CODEC_ID_SONIC_LS = MKBETAG('S','O','N','L'),
491  AV_CODEC_ID_PAF_AUDIO = MKBETAG('P','A','F','A'),
492  AV_CODEC_ID_OPUS = MKBETAG('O','P','U','S'),
493  AV_CODEC_ID_TAK = MKBETAG('t','B','a','K'),
494  AV_CODEC_ID_EVRC = MKBETAG('s','e','v','c'),
495  AV_CODEC_ID_SMV = MKBETAG('s','s','m','v'),
496  AV_CODEC_ID_DSD_LSBF = MKBETAG('D','S','D','L'),
497  AV_CODEC_ID_DSD_MSBF = MKBETAG('D','S','D','M'),
500 
501  /* subtitle codecs */
502  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
505  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
512  AV_CODEC_ID_MICRODVD = MKBETAG('m','D','V','D'),
513  AV_CODEC_ID_EIA_608 = MKBETAG('c','6','0','8'),
514  AV_CODEC_ID_JACOSUB = MKBETAG('J','S','U','B'),
515  AV_CODEC_ID_SAMI = MKBETAG('S','A','M','I'),
516  AV_CODEC_ID_REALTEXT = MKBETAG('R','T','X','T'),
517  AV_CODEC_ID_SUBVIEWER1 = MKBETAG('S','b','V','1'),
518  AV_CODEC_ID_SUBVIEWER = MKBETAG('S','u','b','V'),
519  AV_CODEC_ID_SUBRIP = MKBETAG('S','R','i','p'),
520  AV_CODEC_ID_WEBVTT = MKBETAG('W','V','T','T'),
521  AV_CODEC_ID_MPL2 = MKBETAG('M','P','L','2'),
522  AV_CODEC_ID_VPLAYER = MKBETAG('V','P','l','r'),
523  AV_CODEC_ID_PJS = MKBETAG('P','h','J','S'),
524  AV_CODEC_ID_ASS = MKBETAG('A','S','S',' '), ///< ASS as defined in Matroska
525 
526  /* other specific kind of codecs (generally used for attachments) */
527  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
528  AV_CODEC_ID_TTF = 0x18000,
529  AV_CODEC_ID_BINTEXT = MKBETAG('B','T','X','T'),
530  AV_CODEC_ID_XBIN = MKBETAG('X','B','I','N'),
531  AV_CODEC_ID_IDF = MKBETAG( 0 ,'I','D','F'),
532  AV_CODEC_ID_OTF = MKBETAG( 0 ,'O','T','F'),
533  AV_CODEC_ID_SMPTE_KLV = MKBETAG('K','L','V','A'),
534  AV_CODEC_ID_DVD_NAV = MKBETAG('D','N','A','V'),
535  AV_CODEC_ID_TIMED_ID3 = MKBETAG('T','I','D','3'),
536  AV_CODEC_ID_BIN_DATA = MKBETAG('D','A','T','A'),
537 
538 
539  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
540 
541  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
542  * stream (only used by libavformat) */
543  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
544  * stream (only used by libavformat) */
545  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
546 
547 #if FF_API_CODEC_ID
548 #include "old_codec_ids.h"
549 #endif
550 };
551 
552 /**
553  * This struct describes the properties of a single codec described by an
554  * AVCodecID.
555  * @see avcodec_get_descriptor()
556  */
557 typedef struct AVCodecDescriptor {
558  enum AVCodecID id;
560  /**
561  * Name of the codec described by this descriptor. It is non-empty and
562  * unique for each codec descriptor. It should contain alphanumeric
563  * characters and '_' only.
564  */
565  const char *name;
566  /**
567  * A more descriptive name for this codec. May be NULL.
568  */
569  const char *long_name;
570  /**
571  * Codec properties, a combination of AV_CODEC_PROP_* flags.
572  */
573  int props;
574 
575  /**
576  * MIME type(s) associated with the codec.
577  * May be NULL; if not, a NULL-terminated array of MIME types.
578  * The first item is always non-NULL and is the preferred MIME type.
579  */
580  const char *const *mime_types;
583 /**
584  * Codec uses only intra compression.
585  * Video codecs only.
586  */
587 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
588 /**
589  * Codec supports lossy compression. Audio and video codecs only.
590  * @note a codec may support both lossy and lossless
591  * compression modes
592  */
593 #define AV_CODEC_PROP_LOSSY (1 << 1)
594 /**
595  * Codec supports lossless compression. Audio and video codecs only.
596  */
597 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
598 /**
599  * Codec supports frame reordering. That is, the coded order (the order in which
600  * the encoded packets are output by the encoders / stored / input to the
601  * decoders) may be different from the presentation order of the corresponding
602  * frames.
603  *
604  * For codecs that do not have this property set, PTS and DTS should always be
605  * equal.
606  */
607 #define AV_CODEC_PROP_REORDER (1 << 3)
608 /**
609  * Subtitle codec is bitmap based
610  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
611  */
612 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
613 /**
614  * Subtitle codec is text based.
615  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
616  */
617 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
619 /**
620  * @ingroup lavc_decoding
621  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
622  * This is mainly needed because some optimized bitstream readers read
623  * 32 or 64 bit at once and could read over the end.<br>
624  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
625  * MPEG bitstreams could cause overread and segfault.
626  */
627 #define FF_INPUT_BUFFER_PADDING_SIZE 32
629 /**
630  * @ingroup lavc_encoding
631  * minimum encoding buffer size
632  * Used to avoid some checks during header writing.
633  */
634 #define FF_MIN_BUFFER_SIZE 16384
637 /**
638  * @ingroup lavc_encoding
639  * motion estimation type.
640  */
642  ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
646  ME_EPZS, ///< enhanced predictive zonal search
647  ME_X1, ///< reserved for experiments
648  ME_HEX, ///< hexagon based search
649  ME_UMH, ///< uneven multi-hexagon search
650  ME_TESA, ///< transformed exhaustive search algorithm
651  ME_ITER=50, ///< iterative search
652 };
654 /**
655  * @ingroup lavc_decoding
656  */
658  /* We leave some space between them for extensions (drop some
659  * keyframes for intra-only or drop just some bidir frames). */
660  AVDISCARD_NONE =-16, ///< discard nothing
661  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
662  AVDISCARD_NONREF = 8, ///< discard all non reference
663  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
664  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
665  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
666  AVDISCARD_ALL = 48, ///< discard all
667 };
679  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
680 };
682 /**
683  * @ingroup lavc_encoding
684  */
685 typedef struct RcOverride{
688  int qscale; // If this is 0 then quality_factor will be used instead.
692 #if FF_API_MAX_BFRAMES
693 /**
694  * @deprecated there is no libavcodec-wide limit on the number of B-frames
695  */
696 #define FF_MAX_B_FRAMES 16
697 #endif
699 /* encoding support
700  These flags can be passed in AVCodecContext.flags before initialization.
701  Note: Not everything is supported yet.
702 */
704 /**
705  * Allow decoders to produce frames with data planes that are not aligned
706  * to CPU requirements (e.g. due to cropping).
707  */
708 #define CODEC_FLAG_UNALIGNED 0x0001
709 #define CODEC_FLAG_QSCALE 0x0002 ///< Use fixed qscale.
710 #define CODEC_FLAG_4MV 0x0004 ///< 4 MV per MB allowed / advanced prediction for H.263.
711 #define CODEC_FLAG_OUTPUT_CORRUPT 0x0008 ///< Output even those frames that might be corrupted
712 #define CODEC_FLAG_QPEL 0x0010 ///< Use qpel MC.
713 #if FF_API_GMC
714 /**
715  * @deprecated use the "gmc" private option of the libxvid encoder
716  */
717 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
718 #endif
719 #if FF_API_MV0
720 /**
721  * @deprecated use the flag "mv0" in the "mpv_flags" private option of the
722  * mpegvideo encoders
723  */
724 #define CODEC_FLAG_MV0 0x0040
725 #endif
726 #if FF_API_INPUT_PRESERVED
727 /**
728  * @deprecated passing reference-counted frames to the encoders replaces this
729  * flag
730  */
731 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
732 #endif
733 #define CODEC_FLAG_PASS1 0x0200 ///< Use internal 2pass ratecontrol in first pass mode.
734 #define CODEC_FLAG_PASS2 0x0400 ///< Use internal 2pass ratecontrol in second pass mode.
735 #define CODEC_FLAG_GRAY 0x2000 ///< Only decode/encode grayscale.
736 #if FF_API_EMU_EDGE
737 /**
738  * @deprecated edges are not used/required anymore. I.e. this flag is now always
739  * set.
740  */
741 #define CODEC_FLAG_EMU_EDGE 0x4000
742 #endif
743 #define CODEC_FLAG_PSNR 0x8000 ///< error[?] variables will be set during encoding.
744 #define CODEC_FLAG_TRUNCATED 0x00010000 /** Input bitstream might be truncated at a random
745  location instead of only at frame boundaries. */
746 #if FF_API_NORMALIZE_AQP
747 /**
748  * @deprecated use the flag "naq" in the "mpv_flags" private option of the
749  * mpegvideo encoders
750  */
751 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000
752 #endif
753 #define CODEC_FLAG_INTERLACED_DCT 0x00040000 ///< Use interlaced DCT.
754 #define CODEC_FLAG_LOW_DELAY 0x00080000 ///< Force low delay.
755 #define CODEC_FLAG_GLOBAL_HEADER 0x00400000 ///< Place global headers in extradata instead of every keyframe.
756 #define CODEC_FLAG_BITEXACT 0x00800000 ///< Use only bitexact stuff (except (I)DCT).
757 /* Fx : Flag for h263+ extra options */
758 #define CODEC_FLAG_AC_PRED 0x01000000 ///< H.263 advanced intra coding / MPEG-4 AC prediction
759 #define CODEC_FLAG_LOOP_FILTER 0x00000800 ///< loop filter
760 #define CODEC_FLAG_INTERLACED_ME 0x20000000 ///< interlaced motion estimation
761 #define CODEC_FLAG_CLOSED_GOP 0x80000000
762 #define CODEC_FLAG2_FAST 0x00000001 ///< Allow non spec compliant speedup tricks.
763 #define CODEC_FLAG2_NO_OUTPUT 0x00000004 ///< Skip bitstream encoding.
764 #define CODEC_FLAG2_LOCAL_HEADER 0x00000008 ///< Place global headers at every keyframe instead of in extradata.
765 #define CODEC_FLAG2_DROP_FRAME_TIMECODE 0x00002000 ///< timecode is in drop frame format. DEPRECATED!!!!
766 #define CODEC_FLAG2_IGNORE_CROP 0x00010000 ///< Discard cropping information from SPS.
768 #define CODEC_FLAG2_CHUNKS 0x00008000 ///< Input bitstream might be truncated at a packet boundaries instead of only at frame boundaries.
769 #define CODEC_FLAG2_SHOW_ALL 0x00400000 ///< Show all frames before the first keyframe
770 #define CODEC_FLAG2_EXPORT_MVS 0x10000000 ///< Export motion vectors through frame side data
772 /* Unsupported options :
773  * Syntax Arithmetic coding (SAC)
774  * Reference Picture Selection
775  * Independent Segment Decoding */
776 /* /Fx */
777 /* codec capabilities */
779 #define CODEC_CAP_DRAW_HORIZ_BAND 0x0001 ///< Decoder can use draw_horiz_band callback.
780 /**
781  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
782  * If not set, it might not use get_buffer() at all or use operations that
783  * assume the buffer was allocated by avcodec_default_get_buffer.
784  */
785 #define CODEC_CAP_DR1 0x0002
786 #define CODEC_CAP_TRUNCATED 0x0008
787 #if FF_API_XVMC
788 /* Codec can export data for HW decoding. This flag indicates that
789  * the codec would call get_format() with list that might contain HW accelerated
790  * pixel formats (XvMC, VDPAU, VAAPI, etc). The application can pick any of them
791  * including raw image format.
792  * The application can use the passed context to determine bitstream version,
793  * chroma format, resolution etc.
794  */
795 #define CODEC_CAP_HWACCEL 0x0010
796 #endif /* FF_API_XVMC */
797 /**
798  * Encoder or decoder requires flushing with NULL input at the end in order to
799  * give the complete and correct output.
800  *
801  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
802  * with NULL data. The user can still send NULL data to the public encode
803  * or decode function, but libavcodec will not pass it along to the codec
804  * unless this flag is set.
805  *
806  * Decoders:
807  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
808  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
809  * returns frames.
810  *
811  * Encoders:
812  * The encoder needs to be fed with NULL data at the end of encoding until the
813  * encoder no longer returns data.
814  *
815  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
816  * flag also means that the encoder must set the pts and duration for
817  * each output packet. If this flag is not set, the pts and duration will
818  * be determined by libavcodec from the input frame.
819  */
820 #define CODEC_CAP_DELAY 0x0020
821 /**
822  * Codec can be fed a final frame with a smaller size.
823  * This can be used to prevent truncation of the last audio samples.
824  */
825 #define CODEC_CAP_SMALL_LAST_FRAME 0x0040
826 #if FF_API_CAP_VDPAU
827 /**
828  * Codec can export data for HW decoding (VDPAU).
829  */
830 #define CODEC_CAP_HWACCEL_VDPAU 0x0080
831 #endif
832 /**
833  * Codec can output multiple frames per AVPacket
834  * Normally demuxers return one frame at a time, demuxers which do not do
835  * are connected to a parser to split what they return into proper frames.
836  * This flag is reserved to the very rare category of codecs which have a
837  * bitstream that cannot be split into frames without timeconsuming
838  * operations like full decoding. Demuxers carring such bitstreams thus
839  * may return multiple frames in a packet. This has many disadvantages like
840  * prohibiting stream copy in many cases thus it should only be considered
841  * as a last resort.
842  */
843 #define CODEC_CAP_SUBFRAMES 0x0100
844 /**
845  * Codec is experimental and is thus avoided in favor of non experimental
846  * encoders
847  */
848 #define CODEC_CAP_EXPERIMENTAL 0x0200
849 /**
850  * Codec should fill in channel configuration and samplerate instead of container
851  */
852 #define CODEC_CAP_CHANNEL_CONF 0x0400
853 #if FF_API_NEG_LINESIZES
854 /**
855  * @deprecated no codecs use this capability
856  */
857 #define CODEC_CAP_NEG_LINESIZES 0x0800
858 #endif
859 /**
860  * Codec supports frame-level multithreading.
861  */
862 #define CODEC_CAP_FRAME_THREADS 0x1000
863 /**
864  * Codec supports slice-based (or partition-based) multithreading.
865  */
866 #define CODEC_CAP_SLICE_THREADS 0x2000
867 /**
868  * Codec supports changed parameters at any point.
869  */
870 #define CODEC_CAP_PARAM_CHANGE 0x4000
871 /**
872  * Codec supports avctx->thread_count == 0 (auto).
873  */
874 #define CODEC_CAP_AUTO_THREADS 0x8000
875 /**
876  * Audio encoder supports receiving a different number of samples in each call.
877  */
878 #define CODEC_CAP_VARIABLE_FRAME_SIZE 0x10000
879 /**
880  * Codec is intra only.
881  */
882 #define CODEC_CAP_INTRA_ONLY 0x40000000
883 /**
884  * Codec is lossless.
885  */
886 #define CODEC_CAP_LOSSLESS 0x80000000
888 #if FF_API_MB_TYPE
889 //The following defines may change, don't expect compatibility if you use them.
890 #define MB_TYPE_INTRA4x4 0x0001
891 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
892 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
893 #define MB_TYPE_16x16 0x0008
894 #define MB_TYPE_16x8 0x0010
895 #define MB_TYPE_8x16 0x0020
896 #define MB_TYPE_8x8 0x0040
897 #define MB_TYPE_INTERLACED 0x0080
898 #define MB_TYPE_DIRECT2 0x0100 //FIXME
899 #define MB_TYPE_ACPRED 0x0200
900 #define MB_TYPE_GMC 0x0400
901 #define MB_TYPE_SKIP 0x0800
902 #define MB_TYPE_P0L0 0x1000
903 #define MB_TYPE_P1L0 0x2000
904 #define MB_TYPE_P0L1 0x4000
905 #define MB_TYPE_P1L1 0x8000
906 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
907 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
908 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
909 #define MB_TYPE_QUANT 0x00010000
910 #define MB_TYPE_CBP 0x00020000
911 //Note bits 24-31 are reserved for codec specific use (h264 ref0, mpeg1 0mv, ...)
912 #endif
914 /**
915  * Pan Scan area.
916  * This specifies the area which should be displayed.
917  * Note there may be multiple such areas for one frame.
918  */
919 typedef struct AVPanScan{
920  /**
921  * id
922  * - encoding: Set by user.
923  * - decoding: Set by libavcodec.
924  */
925  int id;
927  /**
928  * width and height in 1/16 pel
929  * - encoding: Set by user.
930  * - decoding: Set by libavcodec.
931  */
932  int width;
933  int height;
935  /**
936  * position of the top left corner in 1/16 pel for up to 3 fields/frames
937  * - encoding: Set by user.
938  * - decoding: Set by libavcodec.
939  */
940  int16_t position[3][2];
942 
943 #if FF_API_QSCALE_TYPE
944 #define FF_QSCALE_TYPE_MPEG1 0
945 #define FF_QSCALE_TYPE_MPEG2 1
946 #define FF_QSCALE_TYPE_H264 2
947 #define FF_QSCALE_TYPE_VP56 3
948 #endif
949 
950 #if FF_API_GET_BUFFER
951 #define FF_BUFFER_TYPE_INTERNAL 1
952 #define FF_BUFFER_TYPE_USER 2 ///< direct rendering buffers (image is (de)allocated by user)
953 #define FF_BUFFER_TYPE_SHARED 4 ///< Buffer from somewhere else; don't deallocate image (data/base), all other tables are not shared.
954 #define FF_BUFFER_TYPE_COPY 8 ///< Just a (modified) copy of some other buffer, don't deallocate anything.
956 #define FF_BUFFER_HINTS_VALID 0x01 // Buffer hints value is meaningful (if 0 ignore).
957 #define FF_BUFFER_HINTS_READABLE 0x02 // Codec will read from buffer.
958 #define FF_BUFFER_HINTS_PRESERVE 0x04 // User must not alter buffer content.
959 #define FF_BUFFER_HINTS_REUSABLE 0x08 // Codec will reuse the buffer (update).
960 #endif
961 
962 /**
963  * The decoder will keep a reference to the frame and may reuse it later.
964  */
965 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
966 
967 /**
968  * @defgroup lavc_packet AVPacket
969  *
970  * Types and functions for working with AVPacket.
971  * @{
972  */
976 
977  /**
978  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
979  * @code
980  * u32le param_flags
981  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
982  * s32le channel_count
983  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
984  * u64le channel_layout
985  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
986  * s32le sample_rate
987  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
988  * s32le width
989  * s32le height
990  * @endcode
991  */
993 
994  /**
995  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
996  * structures with info about macroblocks relevant to splitting the
997  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
998  * That is, it does not necessarily contain info about all macroblocks,
999  * as long as the distance between macroblocks in the info is smaller
1000  * than the target payload size.
1001  * Each MB info structure is 12 bytes, and is laid out as follows:
1002  * @code
1003  * u32le bit offset from the start of the packet
1004  * u8 current quantizer at the start of the macroblock
1005  * u8 GOB number
1006  * u16le macroblock address within the GOB
1007  * u8 horizontal MV predictor
1008  * u8 vertical MV predictor
1009  * u8 horizontal MV predictor for block number 3
1010  * u8 vertical MV predictor for block number 3
1011  * @endcode
1012  */
1014 
1015  /**
1016  * This side data should be associated with an audio stream and contains
1017  * ReplayGain information in form of the AVReplayGain struct.
1018  */
1020 
1021  /**
1022  * This side data contains a 3x3 transformation matrix describing an affine
1023  * transformation that needs to be applied to the decoded video frames for
1024  * correct presentation.
1025  *
1026  * See libavutil/display.h for a detailed description of the data.
1027  */
1029 
1030  /**
1031  * This side data should be associated with a video stream and contains
1032  * Stereoscopic 3D information in form of the AVStereo3D struct.
1033  */
1035 
1036  /**
1037  * Recommmends skipping the specified number of samples
1038  * @code
1039  * u32le number of samples to skip from start of this packet
1040  * u32le number of samples to skip from end of this packet
1041  * u8 reason for start skip
1042  * u8 reason for end skip (0=padding silence, 1=convergence)
1043  * @endcode
1044  */
1046 
1047  /**
1048  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1049  * the packet may contain "dual mono" audio specific to Japanese DTV
1050  * and if it is true, recommends only the selected channel to be used.
1051  * @code
1052  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1053  * @endcode
1054  */
1056 
1057  /**
1058  * A list of zero terminated key/value strings. There is no end marker for
1059  * the list, so it is required to rely on the side data size to stop.
1060  */
1062 
1063  /**
1064  * Subtitle event position
1065  * @code
1066  * u32le x1
1067  * u32le y1
1068  * u32le x2
1069  * u32le y2
1070  * @endcode
1071  */
1073 
1074  /**
1075  * Data found in BlockAdditional element of matroska container. There is
1076  * no end marker for the data, so it is required to rely on the side data
1077  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1078  * by data.
1079  */
1081 
1082  /**
1083  * The optional first identifier line of a WebVTT cue.
1084  */
1086 
1087  /**
1088  * The optional settings (rendering instructions) that immediately
1089  * follow the timestamp specifier of a WebVTT cue.
1090  */
1092 
1093  /**
1094  * A list of zero terminated key/value strings. There is no end marker for
1095  * the list, so it is required to rely on the side data size to stop. This
1096  * side data includes updated metadata which appeared in the stream.
1097  */
1099 };
1101 typedef struct AVPacketSideData {
1103  int size;
1106 
1107 /**
1108  * This structure stores compressed data. It is typically exported by demuxers
1109  * and then passed as input to decoders, or received as output from encoders and
1110  * then passed to muxers.
1111  *
1112  * For video, it should typically contain one compressed frame. For audio it may
1113  * contain several compressed frames.
1114  *
1115  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1116  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1117  * without libavcodec and libavformat major bump.
1118  *
1119  * The semantics of data ownership depends on the buf or destruct (deprecated)
1120  * fields. If either is set, the packet data is dynamically allocated and is
1121  * valid indefinitely until av_free_packet() is called (which in turn calls
1122  * av_buffer_unref()/the destruct callback to free the data). If neither is set,
1123  * the packet data is typically backed by some static buffer somewhere and is
1124  * only valid for a limited time (e.g. until the next read call when demuxing).
1125  *
1126  * The side data is always allocated with av_malloc() and is freed in
1127  * av_free_packet().
1128  */
1129 typedef struct AVPacket {
1130  /**
1131  * A reference to the reference-counted buffer where the packet data is
1132  * stored.
1133  * May be NULL, then the packet data is not reference-counted.
1134  */
1135  AVBufferRef *buf;
1136  /**
1137  * Presentation timestamp in AVStream->time_base units; the time at which
1138  * the decompressed packet will be presented to the user.
1139  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1140  * pts MUST be larger or equal to dts as presentation cannot happen before
1141  * decompression, unless one wants to view hex dumps. Some formats misuse
1142  * the terms dts and pts/cts to mean something different. Such timestamps
1143  * must be converted to true pts/dts before they are stored in AVPacket.
1144  */
1145  int64_t pts;
1146  /**
1147  * Decompression timestamp in AVStream->time_base units; the time at which
1148  * the packet is decompressed.
1149  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1150  */
1151  int64_t dts;
1153  int size;
1154  int stream_index;
1155  /**
1156  * A combination of AV_PKT_FLAG values
1157  */
1158  int flags;
1159  /**
1160  * Additional packet data that can be provided by the container.
1161  * Packet can contain several types of side information.
1162  */
1164  int side_data_elems;
1165 
1166  /**
1167  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1168  * Equals next_pts - this_pts in presentation order.
1169  */
1170  int duration;
1171 #if FF_API_DESTRUCT_PACKET
1173  void (*destruct)(struct AVPacket *);
1175  void *priv;
1176 #endif
1177  int64_t pos; ///< byte position in stream, -1 if unknown
1178 
1179  /**
1180  * Time difference in AVStream->time_base units from the pts of this
1181  * packet to the point at which the output from the decoder has converged
1182  * independent from the availability of previous frames. That is, the
1183  * frames are virtually identical no matter if decoding started from
1184  * the very first frame or from this keyframe.
1185  * Is AV_NOPTS_VALUE if unknown.
1186  * This field is not the display duration of the current packet.
1187  * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
1188  * set.
1189  *
1190  * The purpose of this field is to allow seeking in streams that have no
1191  * keyframes in the conventional sense. It corresponds to the
1192  * recovery point SEI in H.264 and match_time_delta in NUT. It is also
1193  * essential for some types of subtitle streams to ensure that all
1194  * subtitles are correctly displayed after seeking.
1195  */
1196  int64_t convergence_duration;
1198 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1199 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1206 };
1207 /**
1208  * @}
1209  */
1210 
1211 struct AVCodecInternal;
1216  AV_FIELD_TT, //< Top coded_first, top displayed first
1217  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1218  AV_FIELD_TB, //< Top coded first, bottom displayed first
1219  AV_FIELD_BT, //< Bottom coded first, top displayed first
1220 };
1221 
1222 /**
1223  * main external API structure.
1224  * New fields can be added to the end with minor version bumps.
1225  * Removal, reordering and changes to existing fields require a major
1226  * version bump.
1227  * Please use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1228  * applications.
1229  * sizeof(AVCodecContext) must not be used outside libav*.
1230  */
1231 typedef struct AVCodecContext {
1232  /**
1233  * information on struct for av_log
1234  * - set by avcodec_alloc_context3
1235  */
1237  int log_level_offset;
1239  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1240  const struct AVCodec *codec;
1241 #if FF_API_CODEC_NAME
1242  /**
1243  * @deprecated this field is not used for anything in libavcodec
1244  */
1246  char codec_name[32];
1247 #endif
1248  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1249 
1250  /**
1251  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1252  * This is used to work around some encoder bugs.
1253  * A demuxer should set this to what is stored in the field used to identify the codec.
1254  * If there are multiple such fields in a container then the demuxer should choose the one
1255  * which maximizes the information about the used codec.
1256  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1257  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1258  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1259  * first.
1260  * - encoding: Set by user, if not then the default based on codec_id will be used.
1261  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1262  */
1263  unsigned int codec_tag;
1264 
1265  /**
1266  * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1267  * This is used to work around some encoder bugs.
1268  * - encoding: unused
1269  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1270  */
1271  unsigned int stream_codec_tag;
1273  void *priv_data;
1274 
1275  /**
1276  * Private context used for internal data.
1277  *
1278  * Unlike priv_data, this is not codec-specific. It is used in general
1279  * libavcodec functions.
1280  */
1281  struct AVCodecInternal *internal;
1282 
1283  /**
1284  * Private data of the user, can be used to carry app specific stuff.
1285  * - encoding: Set by user.
1286  * - decoding: Set by user.
1287  */
1288  void *opaque;
1289 
1290  /**
1291  * the average bitrate
1292  * - encoding: Set by user; unused for constant quantizer encoding.
1293  * - decoding: Set by libavcodec. 0 or some bitrate if this info is available in the stream.
1294  */
1295  int bit_rate;
1296 
1297  /**
1298  * number of bits the bitstream is allowed to diverge from the reference.
1299  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1300  * - encoding: Set by user; unused for constant quantizer encoding.
1301  * - decoding: unused
1302  */
1303  int bit_rate_tolerance;
1304 
1305  /**
1306  * Global quality for codecs which cannot change it per frame.
1307  * This should be proportional to MPEG-1/2/4 qscale.
1308  * - encoding: Set by user.
1309  * - decoding: unused
1310  */
1311  int global_quality;
1312 
1313  /**
1314  * - encoding: Set by user.
1315  * - decoding: unused
1316  */
1318 #define FF_COMPRESSION_DEFAULT -1
1319 
1320  /**
1321  * CODEC_FLAG_*.
1322  * - encoding: Set by user.
1323  * - decoding: Set by user.
1324  */
1325  int flags;
1326 
1327  /**
1328  * CODEC_FLAG2_*
1329  * - encoding: Set by user.
1330  * - decoding: Set by user.
1331  */
1332  int flags2;
1333 
1334  /**
1335  * some codecs need / can use extradata like Huffman tables.
1336  * mjpeg: Huffman tables
1337  * rv10: additional flags
1338  * mpeg4: global headers (they can be in the bitstream or here)
1339  * The allocated memory should be FF_INPUT_BUFFER_PADDING_SIZE bytes larger
1340  * than extradata_size to avoid problems if it is read with the bitstream reader.
1341  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1342  * - encoding: Set/allocated/freed by libavcodec.
1343  * - decoding: Set/allocated/freed by user.
1344  */
1346  int extradata_size;
1347 
1348  /**
1349  * This is the fundamental unit of time (in seconds) in terms
1350  * of which frame timestamps are represented. For fixed-fps content,
1351  * timebase should be 1/framerate and timestamp increments should be
1352  * identically 1.
1353  * - encoding: MUST be set by user.
1354  * - decoding: Set by libavcodec.
1355  */
1357 
1358  /**
1359  * For some codecs, the time base is closer to the field rate than the frame rate.
1360  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1361  * if no telecine is used ...
1362  *
1363  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1364  */
1365  int ticks_per_frame;
1366 
1367  /**
1368  * Codec delay.
1369  *
1370  * Encoding: Number of frames delay there will be from the encoder input to
1371  * the decoder output. (we assume the decoder matches the spec)
1372  * Decoding: Number of frames delay in addition to what a standard decoder
1373  * as specified in the spec would produce.
1374  *
1375  * Video:
1376  * Number of frames the decoded output will be delayed relative to the
1377  * encoded input.
1378  *
1379  * Audio:
1380  * For encoding, this is the number of "priming" samples added by the
1381  * encoder to the beginning of the stream. The decoded output will be
1382  * delayed by this many samples relative to the input to the encoder (or
1383  * more, if the decoder adds its own padding).
1384  * The timestamps on the output packets are adjusted by the encoder so
1385  * that they always refer to the first sample of the data actually
1386  * contained in the packet, including any added padding.
1387  * E.g. if the timebase is 1/samplerate and the timestamp of the first
1388  * input sample is 0, the timestamp of the first output packet will be
1389  * -delay.
1390  *
1391  * For decoding, this is the number of samples the decoder needs to
1392  * output before the decoder's output is valid. When seeking, you should
1393  * start decoding this many samples prior to your desired seek point.
1394  *
1395  * - encoding: Set by libavcodec.
1396  * - decoding: Set by libavcodec.
1397  */
1398  int delay;
1399 
1400 
1401  /* video only */
1402  /**
1403  * picture width / height.
1404  * - encoding: MUST be set by user.
1405  * - decoding: May be set by the user before opening the decoder if known e.g.
1406  * from the container. Some decoders will require the dimensions
1407  * to be set by the caller. During decoding, the decoder may
1408  * overwrite those values as required.
1409  */
1410  int width, height;
1411 
1412  /**
1413  * Bitstream width / height, may be different from width/height e.g. when
1414  * the decoded frame is cropped before being output or lowres is enabled.
1415  * - encoding: unused
1416  * - decoding: May be set by the user before opening the decoder if known
1417  * e.g. from the container. During decoding, the decoder may
1418  * overwrite those values as required.
1419  */
1421 
1422 #if FF_API_ASPECT_EXTENDED
1423 #define FF_ASPECT_EXTENDED 15
1424 #endif
1425 
1426  /**
1427  * the number of pictures in a group of pictures, or 0 for intra_only
1428  * - encoding: Set by user.
1429  * - decoding: unused
1430  */
1431  int gop_size;
1432 
1433  /**
1434  * Pixel format, see AV_PIX_FMT_xxx.
1435  * May be set by the demuxer if known from headers.
1436  * May be overridden by the decoder if it knows better.
1437  * - encoding: Set by user.
1438  * - decoding: Set by user if known, overridden by libavcodec if known
1439  */
1440  enum AVPixelFormat pix_fmt;
1441 
1442  /**
1443  * Motion estimation algorithm used for video coding.
1444  * 1 (zero), 2 (full), 3 (log), 4 (phods), 5 (epzs), 6 (x1), 7 (hex),
1445  * 8 (umh), 9 (iter), 10 (tesa) [7, 8, 10 are x264 specific, 9 is snow specific]
1446  * - encoding: MUST be set by user.
1447  * - decoding: unused
1448  */
1449  int me_method;
1450 
1451  /**
1452  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1453  * decoder to draw a horizontal band. It improves cache usage. Not
1454  * all codecs can do that. You must check the codec capabilities
1455  * beforehand.
1456  * When multithreading is used, it may be called from multiple threads
1457  * at the same time; threads might draw different parts of the same AVFrame,
1458  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1459  * in order.
1460  * The function is also used by hardware acceleration APIs.
1461  * It is called at least once during frame decoding to pass
1462  * the data needed for hardware render.
1463  * In that mode instead of pixel data, AVFrame points to
1464  * a structure specific to the acceleration API. The application
1465  * reads the structure and can change some fields to indicate progress
1466  * or mark state.
1467  * - encoding: unused
1468  * - decoding: Set by user.
1469  * @param height the height of the slice
1470  * @param y the y position of the slice
1471  * @param type 1->top field, 2->bottom field, 3->frame
1472  * @param offset offset into the AVFrame.data from which the slice should be read
1473  */
1474  void (*draw_horiz_band)(struct AVCodecContext *s,
1475  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1476  int y, int type, int height);
1477 
1478  /**
1479  * callback to negotiate the pixelFormat
1480  * @param fmt is the list of formats which are supported by the codec,
1481  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1482  * The first is always the native one.
1483  * @return the chosen format
1484  * - encoding: unused
1485  * - decoding: Set by user, if not set the native format will be chosen.
1486  */
1487  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1488 
1489  /**
1490  * maximum number of B-frames between non-B-frames
1491  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1492  * - encoding: Set by user.
1493  * - decoding: unused
1494  */
1495  int max_b_frames;
1496 
1497  /**
1498  * qscale factor between IP and B-frames
1499  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1500  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1501  * - encoding: Set by user.
1502  * - decoding: unused
1503  */
1504  float b_quant_factor;
1505 
1506  /** obsolete FIXME remove */
1508 #define FF_RC_STRATEGY_XVID 1
1510  int b_frame_strategy;
1511 
1512  /**
1513  * qscale offset between IP and B-frames
1514  * - encoding: Set by user.
1515  * - decoding: unused
1516  */
1517  float b_quant_offset;
1518 
1519  /**
1520  * Size of the frame reordering buffer in the decoder.
1521  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1522  * - encoding: Set by libavcodec.
1523  * - decoding: Set by libavcodec.
1524  */
1525  int has_b_frames;
1526 
1527  /**
1528  * 0-> h263 quant 1-> mpeg quant
1529  * - encoding: Set by user.
1530  * - decoding: unused
1531  */
1532  int mpeg_quant;
1533 
1534  /**
1535  * qscale factor between P and I-frames
1536  * If > 0 then the last p frame quantizer will be used (q= lastp_q*factor+offset).
1537  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1538  * - encoding: Set by user.
1539  * - decoding: unused
1540  */
1541  float i_quant_factor;
1542 
1543  /**
1544  * qscale offset between P and I-frames
1545  * - encoding: Set by user.
1546  * - decoding: unused
1547  */
1548  float i_quant_offset;
1549 
1550  /**
1551  * luminance masking (0-> disabled)
1552  * - encoding: Set by user.
1553  * - decoding: unused
1554  */
1555  float lumi_masking;
1556 
1557  /**
1558  * temporary complexity masking (0-> disabled)
1559  * - encoding: Set by user.
1560  * - decoding: unused
1561  */
1562  float temporal_cplx_masking;
1563 
1564  /**
1565  * spatial complexity masking (0-> disabled)
1566  * - encoding: Set by user.
1567  * - decoding: unused
1568  */
1569  float spatial_cplx_masking;
1570 
1571  /**
1572  * p block masking (0-> disabled)
1573  * - encoding: Set by user.
1574  * - decoding: unused
1575  */
1576  float p_masking;
1577 
1578  /**
1579  * darkness masking (0-> disabled)
1580  * - encoding: Set by user.
1581  * - decoding: unused
1582  */
1583  float dark_masking;
1584 
1585  /**
1586  * slice count
1587  * - encoding: Set by libavcodec.
1588  * - decoding: Set by user (or 0).
1589  */
1590  int slice_count;
1591  /**
1592  * prediction method (needed for huffyuv)
1593  * - encoding: Set by user.
1594  * - decoding: unused
1595  */
1597 #define FF_PRED_LEFT 0
1598 #define FF_PRED_PLANE 1
1599 #define FF_PRED_MEDIAN 2
1600 
1601  /**
1602  * slice offsets in the frame in bytes
1603  * - encoding: Set/allocated by libavcodec.
1604  * - decoding: Set/allocated by user (or NULL).
1605  */
1606  int *slice_offset;
1607 
1608  /**
1609  * sample aspect ratio (0 if unknown)
1610  * That is the width of a pixel divided by the height of the pixel.
1611  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1612  * - encoding: Set by user.
1613  * - decoding: Set by libavcodec.
1614  */
1616 
1617  /**
1618  * motion estimation comparison function
1619  * - encoding: Set by user.
1620  * - decoding: unused
1621  */
1622  int me_cmp;
1623  /**
1624  * subpixel motion estimation comparison function
1625  * - encoding: Set by user.
1626  * - decoding: unused
1627  */
1628  int me_sub_cmp;
1629  /**
1630  * macroblock comparison function (not supported yet)
1631  * - encoding: Set by user.
1632  * - decoding: unused
1633  */
1634  int mb_cmp;
1635  /**
1636  * interlaced DCT comparison function
1637  * - encoding: Set by user.
1638  * - decoding: unused
1639  */
1641 #define FF_CMP_SAD 0
1642 #define FF_CMP_SSE 1
1643 #define FF_CMP_SATD 2
1644 #define FF_CMP_DCT 3
1645 #define FF_CMP_PSNR 4
1646 #define FF_CMP_BIT 5
1647 #define FF_CMP_RD 6
1648 #define FF_CMP_ZERO 7
1649 #define FF_CMP_VSAD 8
1650 #define FF_CMP_VSSE 9
1651 #define FF_CMP_NSSE 10
1652 #define FF_CMP_W53 11
1653 #define FF_CMP_W97 12
1654 #define FF_CMP_DCTMAX 13
1655 #define FF_CMP_DCT264 14
1656 #define FF_CMP_CHROMA 256
1657 
1658  /**
1659  * ME diamond size & shape
1660  * - encoding: Set by user.
1661  * - decoding: unused
1662  */
1663  int dia_size;
1664 
1665  /**
1666  * amount of previous MV predictors (2a+1 x 2a+1 square)
1667  * - encoding: Set by user.
1668  * - decoding: unused
1669  */
1671 
1672  /**
1673  * prepass for motion estimation
1674  * - encoding: Set by user.
1675  * - decoding: unused
1676  */
1677  int pre_me;
1678 
1679  /**
1680  * motion estimation prepass comparison function
1681  * - encoding: Set by user.
1682  * - decoding: unused
1683  */
1684  int me_pre_cmp;
1685 
1686  /**
1687  * ME prepass diamond size & shape
1688  * - encoding: Set by user.
1689  * - decoding: unused
1690  */
1691  int pre_dia_size;
1692 
1693  /**
1694  * subpel ME quality
1695  * - encoding: Set by user.
1696  * - decoding: unused
1697  */
1698  int me_subpel_quality;
1699 
1700 #if FF_API_AFD
1701  /**
1702  * DTG active format information (additional aspect ratio
1703  * information only used in DVB MPEG-2 transport streams)
1704  * 0 if not set.
1705  *
1706  * - encoding: unused
1707  * - decoding: Set by decoder.
1708  * @deprecated Deprecated in favor of AVSideData
1709  */
1711 #define FF_DTG_AFD_SAME 8
1712 #define FF_DTG_AFD_4_3 9
1713 #define FF_DTG_AFD_16_9 10
1714 #define FF_DTG_AFD_14_9 11
1715 #define FF_DTG_AFD_4_3_SP_14_9 13
1716 #define FF_DTG_AFD_16_9_SP_14_9 14
1717 #define FF_DTG_AFD_SP_4_3 15
1718 #endif /* FF_API_AFD */
1719 
1720  /**
1721  * maximum motion estimation search range in subpel units
1722  * If 0 then no limit.
1723  *
1724  * - encoding: Set by user.
1725  * - decoding: unused
1726  */
1727  int me_range;
1728 
1729  /**
1730  * intra quantizer bias
1731  * - encoding: Set by user.
1732  * - decoding: unused
1733  */
1735 #define FF_DEFAULT_QUANT_BIAS 999999
1736 
1737  /**
1738  * inter quantizer bias
1739  * - encoding: Set by user.
1740  * - decoding: unused
1741  */
1742  int inter_quant_bias;
1743 
1744  /**
1745  * slice flags
1746  * - encoding: unused
1747  * - decoding: Set by user.
1748  */
1750 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
1751 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
1752 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
1753 
1754 #if FF_API_XVMC
1755  /**
1756  * XVideo Motion Acceleration
1757  * - encoding: forbidden
1758  * - decoding: set by decoder
1759  * @deprecated XvMC doesn't need it anymore.
1760  */
1761  attribute_deprecated int xvmc_acceleration;
1762 #endif /* FF_API_XVMC */
1763 
1764  /**
1765  * macroblock decision mode
1766  * - encoding: Set by user.
1767  * - decoding: unused
1768  */
1770 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
1771 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
1772 #define FF_MB_DECISION_RD 2 ///< rate distortion
1773 
1774  /**
1775  * custom intra quantization matrix
1776  * - encoding: Set by user, can be NULL.
1777  * - decoding: Set by libavcodec.
1778  */
1779  uint16_t *intra_matrix;
1780 
1781  /**
1782  * custom inter quantization matrix
1783  * - encoding: Set by user, can be NULL.
1784  * - decoding: Set by libavcodec.
1785  */
1786  uint16_t *inter_matrix;
1787 
1788  /**
1789  * scene change detection threshold
1790  * 0 is default, larger means fewer detected scene changes.
1791  * - encoding: Set by user.
1792  * - decoding: unused
1793  */
1795 
1796  /**
1797  * noise reduction strength
1798  * - encoding: Set by user.
1799  * - decoding: unused
1800  */
1801  int noise_reduction;
1802 
1803  /**
1804  * Motion estimation threshold below which no motion estimation is
1805  * performed, but instead the user specified motion vectors are used.
1806  *
1807  * - encoding: Set by user.
1808  * - decoding: unused
1809  */
1810  int me_threshold;
1811 
1812  /**
1813  * Macroblock threshold below which the user specified macroblock types will be used.
1814  * - encoding: Set by user.
1815  * - decoding: unused
1816  */
1817  int mb_threshold;
1818 
1819  /**
1820  * precision of the intra DC coefficient - 8
1821  * - encoding: Set by user.
1822  * - decoding: unused
1823  */
1824  int intra_dc_precision;
1825 
1826  /**
1827  * Number of macroblock rows at the top which are skipped.
1828  * - encoding: unused
1829  * - decoding: Set by user.
1830  */
1831  int skip_top;
1832 
1833  /**
1834  * Number of macroblock rows at the bottom which are skipped.
1835  * - encoding: unused
1836  * - decoding: Set by user.
1837  */
1838  int skip_bottom;
1839 
1840  /**
1841  * Border processing masking, raises the quantizer for mbs on the borders
1842  * of the picture.
1843  * - encoding: Set by user.
1844  * - decoding: unused
1845  */
1846  float border_masking;
1847 
1848  /**
1849  * minimum MB lagrange multipler
1850  * - encoding: Set by user.
1851  * - decoding: unused
1852  */
1853  int mb_lmin;
1854 
1855  /**
1856  * maximum MB lagrange multipler
1857  * - encoding: Set by user.
1858  * - decoding: unused
1859  */
1860  int mb_lmax;
1861 
1862  /**
1863  *
1864  * - encoding: Set by user.
1865  * - decoding: unused
1866  */
1868 
1869  /**
1870  *
1871  * - encoding: Set by user.
1872  * - decoding: unused
1873  */
1874  int bidir_refine;
1875 
1876  /**
1877  *
1878  * - encoding: Set by user.
1879  * - decoding: unused
1880  */
1881  int brd_scale;
1882 
1883  /**
1884  * minimum GOP size
1885  * - encoding: Set by user.
1886  * - decoding: unused
1887  */
1888  int keyint_min;
1889 
1890  /**
1891  * number of reference frames
1892  * - encoding: Set by user.
1893  * - decoding: Set by lavc.
1894  */
1895  int refs;
1896 
1897  /**
1898  * chroma qp offset from luma
1899  * - encoding: Set by user.
1900  * - decoding: unused
1901  */
1902  int chromaoffset;
1903 
1904 #if FF_API_UNUSED_MEMBERS
1905  /**
1906  * Multiplied by qscale for each frame and added to scene_change_score.
1907  * - encoding: Set by user.
1908  * - decoding: unused
1909  */
1911 #endif
1912 
1913  /**
1914  *
1915  * Note: Value depends upon the compare function used for fullpel ME.
1916  * - encoding: Set by user.
1917  * - decoding: unused
1918  */
1919  int mv0_threshold;
1920 
1921  /**
1922  * Adjust sensitivity of b_frame_strategy 1.
1923  * - encoding: Set by user.
1924  * - decoding: unused
1925  */
1926  int b_sensitivity;
1927 
1928  /**
1929  * Chromaticity coordinates of the source primaries.
1930  * - encoding: Set by user
1931  * - decoding: Set by libavcodec
1932  */
1934 
1935  /**
1936  * Color Transfer Characteristic.
1937  * - encoding: Set by user
1938  * - decoding: Set by libavcodec
1939  */
1941 
1942  /**
1943  * YUV colorspace type.
1944  * - encoding: Set by user
1945  * - decoding: Set by libavcodec
1946  */
1947  enum AVColorSpace colorspace;
1948 
1949  /**
1950  * MPEG vs JPEG YUV range.
1951  * - encoding: Set by user
1952  * - decoding: Set by libavcodec
1953  */
1955 
1956  /**
1957  * This defines the location of chroma samples.
1958  * - encoding: Set by user
1959  * - decoding: Set by libavcodec
1960  */
1962 
1963  /**
1964  * Number of slices.
1965  * Indicates number of picture subdivisions. Used for parallelized
1966  * decoding.
1967  * - encoding: Set by user
1968  * - decoding: unused
1969  */
1970  int slices;
1971 
1972  /** Field order
1973  * - encoding: set by libavcodec
1974  * - decoding: Set by user.
1975  */
1977 
1978  /* audio only */
1979  int sample_rate; ///< samples per second
1980  int channels; ///< number of audio channels
1981 
1982  /**
1983  * audio sample format
1984  * - encoding: Set by user.
1985  * - decoding: Set by libavcodec.
1986  */
1987  enum AVSampleFormat sample_fmt; ///< sample format
1988 
1989  /* The following data should not be initialized. */
1990  /**
1991  * Number of samples per channel in an audio frame.
1992  *
1993  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
1994  * except the last must contain exactly frame_size samples per channel.
1995  * May be 0 when the codec has CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
1996  * frame size is not restricted.
1997  * - decoding: may be set by some decoders to indicate constant frame size
1998  */
1999  int frame_size;
2000 
2001  /**
2002  * Frame counter, set by libavcodec.
2003  *
2004  * - decoding: total number of frames returned from the decoder so far.
2005  * - encoding: total number of frames passed to the encoder so far.
2006  *
2007  * @note the counter is not incremented if encoding/decoding resulted in
2008  * an error.
2009  */
2010  int frame_number;
2011 
2012  /**
2013  * number of bytes per packet if constant and known or 0
2014  * Used by some WAV based audio codecs.
2015  */
2016  int block_align;
2017 
2018  /**
2019  * Audio cutoff bandwidth (0 means "automatic")
2020  * - encoding: Set by user.
2021  * - decoding: unused
2022  */
2023  int cutoff;
2024 
2025 #if FF_API_REQUEST_CHANNELS
2026  /**
2027  * Decoder should decode to this many channels if it can (0 for default)
2028  * - encoding: unused
2029  * - decoding: Set by user.
2030  * @deprecated Deprecated in favor of request_channel_layout.
2031  */
2033 #endif
2034 
2035  /**
2036  * Audio channel layout.
2037  * - encoding: set by user.
2038  * - decoding: set by user, may be overwritten by libavcodec.
2039  */
2040  uint64_t channel_layout;
2041 
2042  /**
2043  * Request decoder to use this channel layout if it can (0 for default)
2044  * - encoding: unused
2045  * - decoding: Set by user.
2046  */
2047  uint64_t request_channel_layout;
2048 
2049  /**
2050  * Type of service that the audio stream conveys.
2051  * - encoding: Set by user.
2052  * - decoding: Set by libavcodec.
2053  */
2055 
2056  /**
2057  * desired sample format
2058  * - encoding: Not used.
2059  * - decoding: Set by user.
2060  * Decoder will decode to this format if it can.
2061  */
2063 
2064 #if FF_API_GET_BUFFER
2065  /**
2066  * Called at the beginning of each frame to get a buffer for it.
2067  *
2068  * The function will set AVFrame.data[], AVFrame.linesize[].
2069  * AVFrame.extended_data[] must also be set, but it should be the same as
2070  * AVFrame.data[] except for planar audio with more channels than can fit
2071  * in AVFrame.data[]. In that case, AVFrame.data[] shall still contain as
2072  * many data pointers as it can hold.
2073  *
2074  * if CODEC_CAP_DR1 is not set then get_buffer() must call
2075  * avcodec_default_get_buffer() instead of providing buffers allocated by
2076  * some other means.
2077  *
2078  * AVFrame.data[] should be 32- or 16-byte-aligned unless the CPU doesn't
2079  * need it. avcodec_default_get_buffer() aligns the output buffer properly,
2080  * but if get_buffer() is overridden then alignment considerations should
2081  * be taken into account.
2082  *
2083  * @see avcodec_default_get_buffer()
2084  *
2085  * Video:
2086  *
2087  * If pic.reference is set then the frame will be read later by libavcodec.
2088  * avcodec_align_dimensions2() should be used to find the required width and
2089  * height, as they normally need to be rounded up to the next multiple of 16.
2090  *
2091  * If frame multithreading is used and thread_safe_callbacks is set,
2092  * it may be called from a different thread, but not from more than one at
2093  * once. Does not need to be reentrant.
2094  *
2095  * @see release_buffer(), reget_buffer()
2096  * @see avcodec_align_dimensions2()
2097  *
2098  * Audio:
2099  *
2100  * Decoders request a buffer of a particular size by setting
2101  * AVFrame.nb_samples prior to calling get_buffer(). The decoder may,
2102  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2103  * to a smaller value in the output frame.
2104  *
2105  * Decoders cannot use the buffer after returning from
2106  * avcodec_decode_audio4(), so they will not call release_buffer(), as it
2107  * is assumed to be released immediately upon return. In some rare cases,
2108  * a decoder may need to call get_buffer() more than once in a single
2109  * call to avcodec_decode_audio4(). In that case, when get_buffer() is
2110  * called again after it has already been called once, the previously
2111  * acquired buffer is assumed to be released at that time and may not be
2112  * reused by the decoder.
2113  *
2114  * As a convenience, av_samples_get_buffer_size() and
2115  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer()
2116  * functions to find the required data size and to fill data pointers and
2117  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2118  * since all planes must be the same size.
2119  *
2120  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2121  *
2122  * - encoding: unused
2123  * - decoding: Set by libavcodec, user can override.
2124  *
2125  * @deprecated use get_buffer2()
2126  */
2128  int (*get_buffer)(struct AVCodecContext *c, AVFrame *pic);
2129 
2130  /**
2131  * Called to release buffers which were allocated with get_buffer.
2132  * A released buffer can be reused in get_buffer().
2133  * pic.data[*] must be set to NULL.
2134  * May be called from a different thread if frame multithreading is used,
2135  * but not by more than one thread at once, so does not need to be reentrant.
2136  * - encoding: unused
2137  * - decoding: Set by libavcodec, user can override.
2138  *
2139  * @deprecated custom freeing callbacks should be set from get_buffer2()
2140  */
2142  void (*release_buffer)(struct AVCodecContext *c, AVFrame *pic);
2143 
2144  /**
2145  * Called at the beginning of a frame to get cr buffer for it.
2146  * Buffer type (size, hints) must be the same. libavcodec won't check it.
2147  * libavcodec will pass previous buffer in pic, function should return
2148  * same buffer or new buffer with old frame "painted" into it.
2149  * If pic.data[0] == NULL must behave like get_buffer().
2150  * if CODEC_CAP_DR1 is not set then reget_buffer() must call
2151  * avcodec_default_reget_buffer() instead of providing buffers allocated by
2152  * some other means.
2153  * - encoding: unused
2154  * - decoding: Set by libavcodec, user can override.
2155  */
2157  int (*reget_buffer)(struct AVCodecContext *c, AVFrame *pic);
2158 #endif
2159 
2160  /**
2161  * This callback is called at the beginning of each frame to get data
2162  * buffer(s) for it. There may be one contiguous buffer for all the data or
2163  * there may be a buffer per each data plane or anything in between. What
2164  * this means is, you may set however many entries in buf[] you feel necessary.
2165  * Each buffer must be reference-counted using the AVBuffer API (see description
2166  * of buf[] below).
2167  *
2168  * The following fields will be set in the frame before this callback is
2169  * called:
2170  * - format
2171  * - width, height (video only)
2172  * - sample_rate, channel_layout, nb_samples (audio only)
2173  * Their values may differ from the corresponding values in
2174  * AVCodecContext. This callback must use the frame values, not the codec
2175  * context values, to calculate the required buffer size.
2176  *
2177  * This callback must fill the following fields in the frame:
2178  * - data[]
2179  * - linesize[]
2180  * - extended_data:
2181  * * if the data is planar audio with more than 8 channels, then this
2182  * callback must allocate and fill extended_data to contain all pointers
2183  * to all data planes. data[] must hold as many pointers as it can.
2184  * extended_data must be allocated with av_malloc() and will be freed in
2185  * av_frame_unref().
2186  * * otherwise exended_data must point to data
2187  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2188  * the frame's data and extended_data pointers must be contained in these. That
2189  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2190  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2191  * and av_buffer_ref().
2192  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2193  * this callback and filled with the extra buffers if there are more
2194  * buffers than buf[] can hold. extended_buf will be freed in
2195  * av_frame_unref().
2196  *
2197  * If CODEC_CAP_DR1 is not set then get_buffer2() must call
2198  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2199  * some other means.
2200  *
2201  * Each data plane must be aligned to the maximum required by the target
2202  * CPU.
2203  *
2204  * @see avcodec_default_get_buffer2()
2205  *
2206  * Video:
2207  *
2208  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2209  * (read and/or written to if it is writable) later by libavcodec.
2210  *
2211  * avcodec_align_dimensions2() should be used to find the required width and
2212  * height, as they normally need to be rounded up to the next multiple of 16.
2213  *
2214  * Some decoders do not support linesizes changing between frames.
2215  *
2216  * If frame multithreading is used and thread_safe_callbacks is set,
2217  * this callback may be called from a different thread, but not from more
2218  * than one at once. Does not need to be reentrant.
2219  *
2220  * @see avcodec_align_dimensions2()
2221  *
2222  * Audio:
2223  *
2224  * Decoders request a buffer of a particular size by setting
2225  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2226  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2227  * to a smaller value in the output frame.
2228  *
2229  * As a convenience, av_samples_get_buffer_size() and
2230  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2231  * functions to find the required data size and to fill data pointers and
2232  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2233  * since all planes must be the same size.
2234  *
2235  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2236  *
2237  * - encoding: unused
2238  * - decoding: Set by libavcodec, user can override.
2239  */
2240  int (*get_buffer2)(struct AVCodecContext *s, AVFrame *frame, int flags);
2241 
2242  /**
2243  * If non-zero, the decoded audio and video frames returned from
2244  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2245  * and are valid indefinitely. The caller must free them with
2246  * av_frame_unref() when they are not needed anymore.
2247  * Otherwise, the decoded frames must not be freed by the caller and are
2248  * only valid until the next decode call.
2249  *
2250  * - encoding: unused
2251  * - decoding: set by the caller before avcodec_open2().
2252  */
2253  int refcounted_frames;
2254 
2255  /* - encoding parameters */
2256  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2257  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2258 
2259  /**
2260  * minimum quantizer
2261  * - encoding: Set by user.
2262  * - decoding: unused
2263  */
2264  int qmin;
2265 
2266  /**
2267  * maximum quantizer
2268  * - encoding: Set by user.
2269  * - decoding: unused
2270  */
2271  int qmax;
2272 
2273  /**
2274  * maximum quantizer difference between frames
2275  * - encoding: Set by user.
2276  * - decoding: unused
2277  */
2278  int max_qdiff;
2279 
2280  /**
2281  * ratecontrol qmin qmax limiting method
2282  * 0-> clipping, 1-> use a nice continuous function to limit qscale within qmin/qmax.
2283  * - encoding: Set by user.
2284  * - decoding: unused
2285  */
2286  float rc_qsquish;
2289  int rc_qmod_freq;
2290 
2291  /**
2292  * decoder bitstream buffer size
2293  * - encoding: Set by user.
2294  * - decoding: unused
2295  */
2296  int rc_buffer_size;
2297 
2298  /**
2299  * ratecontrol override, see RcOverride
2300  * - encoding: Allocated/set/freed by user.
2301  * - decoding: unused
2302  */
2305 
2306  /**
2307  * rate control equation
2308  * - encoding: Set by user
2309  * - decoding: unused
2310  */
2311  const char *rc_eq;
2312 
2313  /**
2314  * maximum bitrate
2315  * - encoding: Set by user.
2316  * - decoding: Set by libavcodec.
2317  */
2318  int rc_max_rate;
2319 
2320  /**
2321  * minimum bitrate
2322  * - encoding: Set by user.
2323  * - decoding: unused
2324  */
2325  int rc_min_rate;
2327  float rc_buffer_aggressivity;
2328 
2329  /**
2330  * initial complexity for pass1 ratecontrol
2331  * - encoding: Set by user.
2332  * - decoding: unused
2333  */
2334  float rc_initial_cplx;
2335 
2336  /**
2337  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2338  * - encoding: Set by user.
2339  * - decoding: unused.
2340  */
2342 
2343  /**
2344  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2345  * - encoding: Set by user.
2346  * - decoding: unused.
2347  */
2349 
2350  /**
2351  * Number of bits which should be loaded into the rc buffer before decoding starts.
2352  * - encoding: Set by user.
2353  * - decoding: unused
2354  */
2357 #define FF_CODER_TYPE_VLC 0
2358 #define FF_CODER_TYPE_AC 1
2359 #define FF_CODER_TYPE_RAW 2
2360 #define FF_CODER_TYPE_RLE 3
2361 #if FF_API_UNUSED_MEMBERS
2362 #define FF_CODER_TYPE_DEFLATE 4
2363 #endif /* FF_API_UNUSED_MEMBERS */
2364  /**
2365  * coder type
2366  * - encoding: Set by user.
2367  * - decoding: unused
2368  */
2369  int coder_type;
2370 
2371  /**
2372  * context model
2373  * - encoding: Set by user.
2374  * - decoding: unused
2375  */
2376  int context_model;
2377 
2378  /**
2379  * minimum Lagrange multiplier
2380  * - encoding: Set by user.
2381  * - decoding: unused
2382  */
2383  int lmin;
2384 
2385  /**
2386  * maximum Lagrange multiplier
2387  * - encoding: Set by user.
2388  * - decoding: unused
2389  */
2390  int lmax;
2391 
2392  /**
2393  * frame skip threshold
2394  * - encoding: Set by user.
2395  * - decoding: unused
2396  */
2398 
2399  /**
2400  * frame skip factor
2401  * - encoding: Set by user.
2402  * - decoding: unused
2403  */
2404  int frame_skip_factor;
2405 
2406  /**
2407  * frame skip exponent
2408  * - encoding: Set by user.
2409  * - decoding: unused
2410  */
2411  int frame_skip_exp;
2412 
2413  /**
2414  * frame skip comparison function
2415  * - encoding: Set by user.
2416  * - decoding: unused
2417  */
2418  int frame_skip_cmp;
2419 
2420  /**
2421  * trellis RD quantization
2422  * - encoding: Set by user.
2423  * - decoding: unused
2424  */
2425  int trellis;
2426 
2427  /**
2428  * - encoding: Set by user.
2429  * - decoding: unused
2430  */
2432 
2433  /**
2434  * - encoding: Set by user.
2435  * - decoding: unused
2436  */
2438 
2439  /**
2440  * GOP timecode frame start number
2441  * - encoding: Set by user, in non drop frame format
2442  * - decoding: Set by libavcodec (timecode in the 25 bits format, -1 if unset)
2443  */
2444  int64_t timecode_frame_start;
2445 
2446  /* The RTP callback: This function is called */
2447  /* every time the encoder has a packet to send. */
2448  /* It depends on the encoder if the data starts */
2449  /* with a Start Code (it should). H.263 does. */
2450  /* mb_nb contains the number of macroblocks */
2451  /* encoded in the RTP payload. */
2452  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2454  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2455  /* do its best to deliver a chunk with size */
2456  /* below rtp_payload_size, the chunk will start */
2457  /* with a start code on some codecs like H.263. */
2458  /* This doesn't take account of any particular */
2459  /* headers inside the transmitted RTP payload. */
2460 
2461  /* statistics, used for 2-pass encoding */
2462  int mv_bits;
2466  int i_count;
2467  int p_count;
2469  int misc_bits;
2470 
2471  /**
2472  * number of bits used for the previously encoded frame
2473  * - encoding: Set by libavcodec.
2474  * - decoding: unused
2475  */
2476  int frame_bits;
2477 
2478  /**
2479  * pass1 encoding statistics output buffer
2480  * - encoding: Set by libavcodec.
2481  * - decoding: unused
2482  */
2483  char *stats_out;
2484 
2485  /**
2486  * pass2 encoding statistics input buffer
2487  * Concatenated stuff from stats_out of pass1 should be placed here.
2488  * - encoding: Allocated/set/freed by user.
2489  * - decoding: unused
2490  */
2491  char *stats_in;
2492 
2493  /**
2494  * Work around bugs in encoders which sometimes cannot be detected automatically.
2495  * - encoding: Set by user
2496  * - decoding: Set by user
2497  */
2499 #define FF_BUG_AUTODETECT 1 ///< autodetection
2500 #if FF_API_OLD_MSMPEG4
2501 #define FF_BUG_OLD_MSMPEG4 2
2502 #endif
2503 #define FF_BUG_XVID_ILACE 4
2504 #define FF_BUG_UMP4 8
2505 #define FF_BUG_NO_PADDING 16
2506 #define FF_BUG_AMV 32
2507 #if FF_API_AC_VLC
2508 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2509 #endif
2510 #define FF_BUG_QPEL_CHROMA 64
2511 #define FF_BUG_STD_QPEL 128
2512 #define FF_BUG_QPEL_CHROMA2 256
2513 #define FF_BUG_DIRECT_BLOCKSIZE 512
2514 #define FF_BUG_EDGE 1024
2515 #define FF_BUG_HPEL_CHROMA 2048
2516 #define FF_BUG_DC_CLIP 4096
2517 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2518 #define FF_BUG_TRUNCATED 16384
2519 
2520  /**
2521  * strictly follow the standard (MPEG4, ...).
2522  * - encoding: Set by user.
2523  * - decoding: Set by user.
2524  * Setting this to STRICT or higher means the encoder and decoder will
2525  * generally do stupid things, whereas setting it to unofficial or lower
2526  * will mean the encoder might produce output that is not supported by all
2527  * spec-compliant decoders. Decoders don't differentiate between normal,
2528  * unofficial and experimental (that is, they always try to decode things
2529  * when they can) unless they are explicitly asked to behave stupidly
2530  * (=strictly conform to the specs)
2531  */
2533 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2534 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2535 #define FF_COMPLIANCE_NORMAL 0
2536 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2537 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2538 
2539  /**
2540  * error concealment flags
2541  * - encoding: unused
2542  * - decoding: Set by user.
2543  */
2545 #define FF_EC_GUESS_MVS 1
2546 #define FF_EC_DEBLOCK 2
2547 #define FF_EC_FAVOR_INTER 256
2548 
2549  /**
2550  * debug
2551  * - encoding: Set by user.
2552  * - decoding: Set by user.
2553  */
2554  int debug;
2555 #define FF_DEBUG_PICT_INFO 1
2556 #define FF_DEBUG_RC 2
2557 #define FF_DEBUG_BITSTREAM 4
2558 #define FF_DEBUG_MB_TYPE 8
2559 #define FF_DEBUG_QP 16
2560 #if FF_API_DEBUG_MV
2561 /**
2562  * @deprecated this option does nothing
2563  */
2564 #define FF_DEBUG_MV 32
2565 #endif
2566 #define FF_DEBUG_DCT_COEFF 0x00000040
2567 #define FF_DEBUG_SKIP 0x00000080
2568 #define FF_DEBUG_STARTCODE 0x00000100
2569 #if FF_API_UNUSED_MEMBERS
2570 #define FF_DEBUG_PTS 0x00000200
2571 #endif /* FF_API_UNUSED_MEMBERS */
2572 #define FF_DEBUG_ER 0x00000400
2573 #define FF_DEBUG_MMCO 0x00000800
2574 #define FF_DEBUG_BUGS 0x00001000
2575 #if FF_API_DEBUG_MV
2576 #define FF_DEBUG_VIS_QP 0x00002000 ///< only access through AVOptions from outside libavcodec
2577 #define FF_DEBUG_VIS_MB_TYPE 0x00004000 ///< only access through AVOptions from outside libavcodec
2578 #endif
2579 #define FF_DEBUG_BUFFERS 0x00008000
2580 #define FF_DEBUG_THREADS 0x00010000
2581 #define FF_DEBUG_NOMC 0x01000000
2582 
2583 #if FF_API_DEBUG_MV
2584  /**
2585  * debug
2586  * Code outside libavcodec should access this field using AVOptions
2587  * - encoding: Set by user.
2588  * - decoding: Set by user.
2589  */
2591 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
2592 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
2593 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
2594 #endif
2595 
2596  /**
2597  * Error recognition; may misdetect some more or less valid parts as errors.
2598  * - encoding: unused
2599  * - decoding: Set by user.
2600  */
2601  int err_recognition;
2602 
2603 /**
2604  * Verify checksums embedded in the bitstream (could be of either encoded or
2605  * decoded data, depending on the codec) and print an error message on mismatch.
2606  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2607  * decoder returning an error.
2608  */
2609 #define AV_EF_CRCCHECK (1<<0)
2610 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2611 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2612 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2614 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2615 #define AV_EF_CAREFUL (1<<16) ///< consider things that violate the spec, are fast to calculate and have not been seen in the wild as errors
2616 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2617 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2618 
2619 
2620  /**
2621  * opaque 64bit number (generally a PTS) that will be reordered and
2622  * output in AVFrame.reordered_opaque
2623  * - encoding: unused
2624  * - decoding: Set by user.
2625  */
2626  int64_t reordered_opaque;
2627 
2628  /**
2629  * Hardware accelerator in use
2630  * - encoding: unused.
2631  * - decoding: Set by libavcodec
2632  */
2633  struct AVHWAccel *hwaccel;
2634 
2635  /**
2636  * Hardware accelerator context.
2637  * For some hardware accelerators, a global context needs to be
2638  * provided by the user. In that case, this holds display-dependent
2639  * data FFmpeg cannot instantiate itself. Please refer to the
2640  * FFmpeg HW accelerator documentation to know how to fill this
2641  * is. e.g. for VA API, this is a struct vaapi_context.
2642  * - encoding: unused
2643  * - decoding: Set by user
2644  */
2645  void *hwaccel_context;
2646 
2647  /**
2648  * error
2649  * - encoding: Set by libavcodec if flags&CODEC_FLAG_PSNR.
2650  * - decoding: unused
2651  */
2652  uint64_t error[AV_NUM_DATA_POINTERS];
2653 
2654  /**
2655  * DCT algorithm, see FF_DCT_* below
2656  * - encoding: Set by user.
2657  * - decoding: unused
2658  */
2660 #define FF_DCT_AUTO 0
2661 #define FF_DCT_FASTINT 1
2662 #if FF_API_UNUSED_MEMBERS
2663 #define FF_DCT_INT 2
2664 #endif /* FF_API_UNUSED_MEMBERS */
2665 #define FF_DCT_MMX 3
2666 #define FF_DCT_ALTIVEC 5
2667 #define FF_DCT_FAAN 6
2668 
2669  /**
2670  * IDCT algorithm, see FF_IDCT_* below.
2671  * - encoding: Set by user.
2672  * - decoding: Set by user.
2673  */
2675 #define FF_IDCT_AUTO 0
2676 #define FF_IDCT_INT 1
2677 #define FF_IDCT_SIMPLE 2
2678 #define FF_IDCT_SIMPLEMMX 3
2679 #define FF_IDCT_ARM 7
2680 #define FF_IDCT_ALTIVEC 8
2681 #if FF_API_ARCH_SH4
2682 #define FF_IDCT_SH4 9
2683 #endif
2684 #define FF_IDCT_SIMPLEARM 10
2685 #if FF_API_UNUSED_MEMBERS
2686 #define FF_IDCT_IPP 13
2687 #endif /* FF_API_UNUSED_MEMBERS */
2688 #define FF_IDCT_XVID 14
2689 #if FF_API_IDCT_XVIDMMX
2690 #define FF_IDCT_XVIDMMX 14
2691 #endif /* FF_API_IDCT_XVIDMMX */
2692 #define FF_IDCT_SIMPLEARMV5TE 16
2693 #define FF_IDCT_SIMPLEARMV6 17
2694 #if FF_API_ARCH_SPARC
2695 #define FF_IDCT_SIMPLEVIS 18
2696 #endif
2697 #define FF_IDCT_FAAN 20
2698 #define FF_IDCT_SIMPLENEON 22
2699 #if FF_API_ARCH_ALPHA
2700 #define FF_IDCT_SIMPLEALPHA 23
2701 #endif
2702 #define FF_IDCT_SIMPLEAUTO 128
2703 
2704  /**
2705  * bits per sample/pixel from the demuxer (needed for huffyuv).
2706  * - encoding: Set by libavcodec.
2707  * - decoding: Set by user.
2708  */
2710 
2711  /**
2712  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2713  * - encoding: set by user.
2714  * - decoding: set by libavcodec.
2715  */
2716  int bits_per_raw_sample;
2717 
2718 #if FF_API_LOWRES
2719  /**
2720  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2721  * - encoding: unused
2722  * - decoding: Set by user.
2723  * Code outside libavcodec should access this field using:
2724  * av_codec_{get,set}_lowres(avctx)
2725  */
2726  int lowres;
2727 #endif
2728 
2729  /**
2730  * the picture in the bitstream
2731  * - encoding: Set by libavcodec.
2732  * - decoding: unused
2733  */
2735 
2736  /**
2737  * thread count
2738  * is used to decide how many independent tasks should be passed to execute()
2739  * - encoding: Set by user.
2740  * - decoding: Set by user.
2741  */
2742  int thread_count;
2743 
2744  /**
2745  * Which multithreading methods to use.
2746  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2747  * so clients which cannot provide future frames should not use it.
2748  *
2749  * - encoding: Set by user, otherwise the default is used.
2750  * - decoding: Set by user, otherwise the default is used.
2751  */
2753 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2754 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2755 
2756  /**
2757  * Which multithreading methods are in use by the codec.
2758  * - encoding: Set by libavcodec.
2759  * - decoding: Set by libavcodec.
2760  */
2761  int active_thread_type;
2762 
2763  /**
2764  * Set by the client if its custom get_buffer() callback can be called
2765  * synchronously from another thread, which allows faster multithreaded decoding.
2766  * draw_horiz_band() will be called from other threads regardless of this setting.
2767  * Ignored if the default get_buffer() is used.
2768  * - encoding: Set by user.
2769  * - decoding: Set by user.
2770  */
2772 
2773  /**
2774  * The codec may call this to execute several independent things.
2775  * It will return only after finishing all tasks.
2776  * The user may replace this with some multithreaded implementation,
2777  * the default implementation will execute the parts serially.
2778  * @param count the number of things to execute
2779  * - encoding: Set by libavcodec, user can override.
2780  * - decoding: Set by libavcodec, user can override.
2781  */
2782  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2783 
2784  /**
2785  * The codec may call this to execute several independent things.
2786  * It will return only after finishing all tasks.
2787  * The user may replace this with some multithreaded implementation,
2788  * the default implementation will execute the parts serially.
2789  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2790  * @param c context passed also to func
2791  * @param count the number of things to execute
2792  * @param arg2 argument passed unchanged to func
2793  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2794  * @param func function that will be called count times, with jobnr from 0 to count-1.
2795  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2796  * two instances of func executing at the same time will have the same threadnr.
2797  * @return always 0 currently, but code should handle a future improvement where when any call to func
2798  * returns < 0 no further calls to func may be done and < 0 is returned.
2799  * - encoding: Set by libavcodec, user can override.
2800  * - decoding: Set by libavcodec, user can override.
2801  */
2802  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2803 
2804 #if FF_API_THREAD_OPAQUE
2805  /**
2806  * @deprecated this field should not be used from outside of lavc
2807  */
2809  void *thread_opaque;
2810 #endif
2811 
2812  /**
2813  * noise vs. sse weight for the nsse comparison function
2814  * - encoding: Set by user.
2815  * - decoding: unused
2816  */
2817  int nsse_weight;
2818 
2819  /**
2820  * profile
2821  * - encoding: Set by user.
2822  * - decoding: Set by libavcodec.
2823  */
2824  int profile;
2825 #define FF_PROFILE_UNKNOWN -99
2826 #define FF_PROFILE_RESERVED -100
2828 #define FF_PROFILE_AAC_MAIN 0
2829 #define FF_PROFILE_AAC_LOW 1
2830 #define FF_PROFILE_AAC_SSR 2
2831 #define FF_PROFILE_AAC_LTP 3
2832 #define FF_PROFILE_AAC_HE 4
2833 #define FF_PROFILE_AAC_HE_V2 28
2834 #define FF_PROFILE_AAC_LD 22
2835 #define FF_PROFILE_AAC_ELD 38
2836 #define FF_PROFILE_MPEG2_AAC_LOW 128
2837 #define FF_PROFILE_MPEG2_AAC_HE 131
2839 #define FF_PROFILE_DTS 20
2840 #define FF_PROFILE_DTS_ES 30
2841 #define FF_PROFILE_DTS_96_24 40
2842 #define FF_PROFILE_DTS_HD_HRA 50
2843 #define FF_PROFILE_DTS_HD_MA 60
2845 #define FF_PROFILE_MPEG2_422 0
2846 #define FF_PROFILE_MPEG2_HIGH 1
2847 #define FF_PROFILE_MPEG2_SS 2
2848 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2849 #define FF_PROFILE_MPEG2_MAIN 4
2850 #define FF_PROFILE_MPEG2_SIMPLE 5
2852 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2853 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2855 #define FF_PROFILE_H264_BASELINE 66
2856 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2857 #define FF_PROFILE_H264_MAIN 77
2858 #define FF_PROFILE_H264_EXTENDED 88
2859 #define FF_PROFILE_H264_HIGH 100
2860 #define FF_PROFILE_H264_HIGH_10 110
2861 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2862 #define FF_PROFILE_H264_HIGH_422 122
2863 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2864 #define FF_PROFILE_H264_HIGH_444 144
2865 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2866 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2867 #define FF_PROFILE_H264_CAVLC_444 44
2869 #define FF_PROFILE_VC1_SIMPLE 0
2870 #define FF_PROFILE_VC1_MAIN 1
2871 #define FF_PROFILE_VC1_COMPLEX 2
2872 #define FF_PROFILE_VC1_ADVANCED 3
2874 #define FF_PROFILE_MPEG4_SIMPLE 0
2875 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2876 #define FF_PROFILE_MPEG4_CORE 2
2877 #define FF_PROFILE_MPEG4_MAIN 3
2878 #define FF_PROFILE_MPEG4_N_BIT 4
2879 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2880 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2881 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2882 #define FF_PROFILE_MPEG4_HYBRID 8
2883 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2884 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2885 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2886 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2887 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2888 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2889 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2891 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 0
2892 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 1
2893 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 2
2894 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2895 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2896 
2898 #define FF_PROFILE_HEVC_MAIN 1
2899 #define FF_PROFILE_HEVC_MAIN_10 2
2900 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2901 #define FF_PROFILE_HEVC_REXT 4
2902 
2903  /**
2904  * level
2905  * - encoding: Set by user.
2906  * - decoding: Set by libavcodec.
2907  */
2908  int level;
2909 #define FF_LEVEL_UNKNOWN -99
2910 
2911  /**
2912  * Skip loop filtering for selected frames.
2913  * - encoding: unused
2914  * - decoding: Set by user.
2915  */
2917 
2918  /**
2919  * Skip IDCT/dequantization for selected frames.
2920  * - encoding: unused
2921  * - decoding: Set by user.
2922  */
2923  enum AVDiscard skip_idct;
2924 
2925  /**
2926  * Skip decoding for selected frames.
2927  * - encoding: unused
2928  * - decoding: Set by user.
2929  */
2930  enum AVDiscard skip_frame;
2931 
2932  /**
2933  * Header containing style information for text subtitles.
2934  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
2935  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
2936  * the Format line following. It shouldn't include any Dialogue line.
2937  * - encoding: Set/allocated/freed by user (before avcodec_open2())
2938  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
2939  */
2942 
2943 #if FF_API_ERROR_RATE
2944  /**
2945  * @deprecated use the 'error_rate' private AVOption of the mpegvideo
2946  * encoders
2947  */
2949  int error_rate;
2950 #endif
2951 
2952 #if FF_API_CODEC_PKT
2953  /**
2954  * @deprecated this field is not supposed to be accessed from outside lavc
2955  */
2957  AVPacket *pkt;
2958 #endif
2959 
2960  /**
2961  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
2962  * Used for compliant TS muxing.
2963  * - encoding: Set by libavcodec.
2964  * - decoding: unused.
2965  */
2966  uint64_t vbv_delay;
2967 
2968  /**
2969  * Encoding only. Allow encoders to output packets that do not contain any
2970  * encoded data, only side data.
2971  *
2972  * Some encoders need to output such packets, e.g. to update some stream
2973  * parameters at the end of encoding.
2974  *
2975  * All callers are strongly recommended to set this option to 1 and update
2976  * their code to deal with such packets, since this behaviour may become
2977  * always enabled in the future (then this option will be deprecated and
2978  * later removed). To avoid ABI issues when this happens, the callers should
2979  * use AVOptions to set this field.
2980  */
2982 
2983  /**
2984  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
2985  * Code outside libavcodec should access this field using:
2986  * av_codec_{get,set}_pkt_timebase(avctx)
2987  * - encoding unused.
2988  * - decoding set by user.
2989  */
2991 
2992  /**
2993  * AVCodecDescriptor
2994  * Code outside libavcodec should access this field using:
2995  * av_codec_{get,set}_codec_descriptor(avctx)
2996  * - encoding: unused.
2997  * - decoding: set by libavcodec.
2998  */
3000 
3001 #if !FF_API_LOWRES
3002  /**
3003  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3004  * - encoding: unused
3005  * - decoding: Set by user.
3006  * Code outside libavcodec should access this field using:
3007  * av_codec_{get,set}_lowres(avctx)
3008  */
3009  int lowres;
3010 #endif
3011 
3012  /**
3013  * Current statistics for PTS correction.
3014  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3015  * - encoding: unused
3016  */
3017  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3018  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3019  int64_t pts_correction_last_pts; /// PTS of the last frame
3020  int64_t pts_correction_last_dts; /// DTS of the last frame
3021 
3022  /**
3023  * Character encoding of the input subtitles file.
3024  * - decoding: set by user
3025  * - encoding: unused
3026  */
3027  char *sub_charenc;
3028 
3029  /**
3030  * Subtitles character encoding mode. Formats or codecs might be adjusting
3031  * this setting (if they are doing the conversion themselves for instance).
3032  * - decoding: set by libavcodec
3033  * - encoding: unused
3034  */
3036 #define FF_SUB_CHARENC_MODE_DO_NOTHING -1 ///< do nothing (demuxer outputs a stream supposed to be already in UTF-8, or the codec is bitmap for instance)
3037 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3038 #define FF_SUB_CHARENC_MODE_PRE_DECODER 1 ///< the AVPacket data needs to be recoded to UTF-8 before being fed to the decoder, requires iconv
3039 
3040  /**
3041  * Skip processing alpha if supported by codec.
3042  * Note that if the format uses pre-multiplied alpha (common with VP6,
3043  * and recommended due to better video quality/compression)
3044  * the image will look as if alpha-blended onto a black background.
3045  * However for formats that do not use pre-multiplied alpha
3046  * there might be serious artefacts (though e.g. libswscale currently
3047  * assumes pre-multiplied alpha anyway).
3048  * Code outside libavcodec should access this field using AVOptions
3049  *
3050  * - decoding: set by user
3051  * - encoding: unused
3052  */
3053  int skip_alpha;
3054 
3055  /**
3056  * Number of samples to skip after a discontinuity
3057  * - decoding: unused
3058  * - encoding: set by libavcodec
3059  */
3060  int seek_preroll;
3061 
3062 #if !FF_API_DEBUG_MV
3063  /**
3064  * debug motion vectors
3065  * Code outside libavcodec should access this field using AVOptions
3066  * - encoding: Set by user.
3067  * - decoding: Set by user.
3068  */
3069  int debug_mv;
3070 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3071 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3072 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3073 #endif
3074 
3075  /**
3076  * custom intra quantization matrix
3077  * Code outside libavcodec should access this field using av_codec_g/set_chroma_intra_matrix()
3078  * - encoding: Set by user, can be NULL.
3079  * - decoding: unused.
3080  */
3081  uint16_t *chroma_intra_matrix;
3082 } AVCodecContext;
3083 
3086 
3089 
3090 int av_codec_get_lowres(const AVCodecContext *avctx);
3091 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3092 
3093 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3094 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3095 
3096 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3097 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3098 
3099 /**
3100  * AVProfile.
3101  */
3102 typedef struct AVProfile {
3103  int profile;
3104  const char *name; ///< short name for the profile
3105 } AVProfile;
3106 
3107 typedef struct AVCodecDefault AVCodecDefault;
3108 
3109 struct AVSubtitle;
3110 
3111 /**
3112  * AVCodec.
3113  */
3114 typedef struct AVCodec {
3115  /**
3116  * Name of the codec implementation.
3117  * The name is globally unique among encoders and among decoders (but an
3118  * encoder and a decoder can share the same name).
3119  * This is the primary way to find a codec from the user perspective.
3120  */
3121  const char *name;
3122  /**
3123  * Descriptive name for the codec, meant to be more human readable than name.
3124  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3125  */
3126  const char *long_name;
3128  enum AVCodecID id;
3129  /**
3130  * Codec capabilities.
3131  * see CODEC_CAP_*
3132  */
3134  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3135  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3136  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3137  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3138  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3139 #if FF_API_LOWRES
3140  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder, no direct access, use av_codec_get_max_lowres()
3141 #endif
3142  const AVClass *priv_class; ///< AVClass for the private context
3143  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3144 
3145  /*****************************************************************
3146  * No fields below this line are part of the public API. They
3147  * may not be used outside of libavcodec and can be changed and
3148  * removed at will.
3149  * New public fields should be added right above.
3150  *****************************************************************
3151  */
3153  struct AVCodec *next;
3154  /**
3155  * @name Frame-level threading support functions
3156  * @{
3157  */
3158  /**
3159  * If defined, called on thread contexts when they are created.
3160  * If the codec allocates writable tables in init(), re-allocate them here.
3161  * priv_data will be set to a copy of the original.
3162  */
3163  int (*init_thread_copy)(AVCodecContext *);
3164  /**
3165  * Copy necessary context variables from a previous thread context to the current one.
3166  * If not defined, the next thread will start automatically; otherwise, the codec
3167  * must call ff_thread_finish_setup().
3168  *
3169  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3170  */
3172  /** @} */
3173 
3174  /**
3175  * Private codec-specific defaults.
3176  */
3177  const AVCodecDefault *defaults;
3178 
3179  /**
3180  * Initialize codec static data, called from avcodec_register().
3181  */
3182  void (*init_static_data)(struct AVCodec *codec);
3185  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3186  const struct AVSubtitle *sub);
3187  /**
3188  * Encode data to an AVPacket.
3189  *
3190  * @param avctx codec context
3191  * @param avpkt output AVPacket (may contain a user-provided buffer)
3192  * @param[in] frame AVFrame containing the raw data to be encoded
3193  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3194  * non-empty packet was returned in avpkt.
3195  * @return 0 on success, negative error code on failure
3196  */
3197  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3198  int *got_packet_ptr);
3199  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3200  int (*close)(AVCodecContext *);
3201  /**
3202  * Flush buffers.
3203  * Will be called when seeking
3204  */
3205  void (*flush)(AVCodecContext *);
3206 } AVCodec;
3207 
3208 int av_codec_get_max_lowres(const AVCodec *codec);
3209 
3210 struct MpegEncContext;
3211 
3212 /**
3213  * AVHWAccel.
3214  */
3215 typedef struct AVHWAccel {
3216  /**
3217  * Name of the hardware accelerated codec.
3218  * The name is globally unique among encoders and among decoders (but an
3219  * encoder and a decoder can share the same name).
3220  */
3221  const char *name;
3222 
3223  /**
3224  * Type of codec implemented by the hardware accelerator.
3225  *
3226  * See AVMEDIA_TYPE_xxx
3227  */
3228  enum AVMediaType type;
3229 
3230  /**
3231  * Codec implemented by the hardware accelerator.
3232  *
3233  * See AV_CODEC_ID_xxx
3234  */
3235  enum AVCodecID id;
3236 
3237  /**
3238  * Supported pixel format.
3239  *
3240  * Only hardware accelerated formats are supported here.
3241  */
3242  enum AVPixelFormat pix_fmt;
3243 
3244  /**
3245  * Hardware accelerated codec capabilities.
3246  * see FF_HWACCEL_CODEC_CAP_*
3247  */
3248  int capabilities;
3249 
3250  /*****************************************************************
3251  * No fields below this line are part of the public API. They
3252  * may not be used outside of libavcodec and can be changed and
3253  * removed at will.
3254  * New public fields should be added right above.
3255  *****************************************************************
3256  */
3257  struct AVHWAccel *next;
3258 
3259  /**
3260  * Allocate a custom buffer
3261  */
3262  int (*alloc_frame)(AVCodecContext *avctx, AVFrame *frame);
3263 
3264  /**
3265  * Called at the beginning of each frame or field picture.
3266  *
3267  * Meaningful frame information (codec specific) is guaranteed to
3268  * be parsed at this point. This function is mandatory.
3269  *
3270  * Note that buf can be NULL along with buf_size set to 0.
3271  * Otherwise, this means the whole frame is available at this point.
3272  *
3273  * @param avctx the codec context
3274  * @param buf the frame data buffer base
3275  * @param buf_size the size of the frame in bytes
3276  * @return zero if successful, a negative value otherwise
3277  */
3278  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3279 
3280  /**
3281  * Callback for each slice.
3282  *
3283  * Meaningful slice information (codec specific) is guaranteed to
3284  * be parsed at this point. This function is mandatory.
3285  * The only exception is XvMC, that works on MB level.
3286  *
3287  * @param avctx the codec context
3288  * @param buf the slice data buffer base
3289  * @param buf_size the size of the slice in bytes
3290  * @return zero if successful, a negative value otherwise
3291  */
3292  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3293 
3294  /**
3295  * Called at the end of each frame or field picture.
3296  *
3297  * The whole picture is parsed at this point and can now be sent
3298  * to the hardware accelerator. This function is mandatory.
3299  *
3300  * @param avctx the codec context
3301  * @return zero if successful, a negative value otherwise
3302  */
3303  int (*end_frame)(AVCodecContext *avctx);
3304 
3305  /**
3306  * Size of per-frame hardware accelerator private data.
3307  *
3308  * Private data is allocated with av_mallocz() before
3309  * AVCodecContext.get_buffer() and deallocated after
3310  * AVCodecContext.release_buffer().
3311  */
3313 
3314  /**
3315  * Called for every Macroblock in a slice.
3316  *
3317  * XvMC uses it to replace the ff_mpv_decode_mb().
3318  * Instead of decoding to raw picture, MB parameters are
3319  * stored in an array provided by the video driver.
3320  *
3321  * @param s the mpeg context
3322  */
3323  void (*decode_mb)(struct MpegEncContext *s);
3324 
3325  /**
3326  * Initialize the hwaccel private data.
3327  *
3328  * This will be called from ff_get_format(), after hwaccel and
3329  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3330  * is allocated.
3331  */
3332  int (*init)(AVCodecContext *avctx);
3333 
3334  /**
3335  * Uninitialize the hwaccel private data.
3336  *
3337  * This will be called from get_format() or avcodec_close(), after hwaccel
3338  * and hwaccel_context are already uninitialized.
3339  */
3340  int (*uninit)(AVCodecContext *avctx);
3341 
3342  /**
3343  * Size of the private data to allocate in
3344  * AVCodecInternal.hwaccel_priv_data.
3345  */
3346  int priv_data_size;
3347 } AVHWAccel;
3348 
3349 /**
3350  * @defgroup lavc_picture AVPicture
3351  *
3352  * Functions for working with AVPicture
3353  * @{
3354  */
3355 
3356 /**
3357  * Picture data structure.
3358  *
3359  * Up to four components can be stored into it, the last component is
3360  * alpha.
3361  */
3362 typedef struct AVPicture {
3363  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3364  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3365 } AVPicture;
3366 
3367 /**
3368  * @}
3369  */
3372  SUBTITLE_NONE,
3374  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3375 
3376  /**
3377  * Plain text, the text field must be set by the decoder and is
3378  * authoritative. ass and pict fields may contain approximations.
3379  */
3380  SUBTITLE_TEXT,
3381 
3382  /**
3383  * Formatted text, the ass field must be set by the decoder and is
3384  * authoritative. pict and text fields may contain approximations.
3385  */
3386  SUBTITLE_ASS,
3387 };
3389 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3391 typedef struct AVSubtitleRect {
3392  int x; ///< top left corner of pict, undefined when pict is not set
3393  int y; ///< top left corner of pict, undefined when pict is not set
3394  int w; ///< width of pict, undefined when pict is not set
3395  int h; ///< height of pict, undefined when pict is not set
3396  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3397 
3398  /**
3399  * data+linesize for the bitmap of this subtitle.
3400  * can be set for text/ass as well once they where rendered
3401  */
3403  enum AVSubtitleType type;
3405  char *text; ///< 0 terminated plain UTF-8 text
3406 
3407  /**
3408  * 0 terminated ASS/SSA compatible event line.
3409  * The presentation of this is unaffected by the other values in this
3410  * struct.
3411  */
3412  char *ass;
3414  int flags;
3415 } AVSubtitleRect;
3417 typedef struct AVSubtitle {
3418  uint16_t format; /* 0 = graphics */
3419  uint32_t start_display_time; /* relative to packet pts, in ms */
3420  uint32_t end_display_time; /* relative to packet pts, in ms */
3421  unsigned num_rects;
3423  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3424 } AVSubtitle;
3425 
3426 /**
3427  * If c is NULL, returns the first registered codec,
3428  * if c is non-NULL, returns the next registered codec after c,
3429  * or NULL if c is the last one.
3430  */
3431 AVCodec *av_codec_next(const AVCodec *c);
3432 
3433 /**
3434  * Return the LIBAVCODEC_VERSION_INT constant.
3435  */
3436 unsigned avcodec_version(void);
3437 
3438 /**
3439  * Return the libavcodec build-time configuration.
3440  */
3441 const char *avcodec_configuration(void);
3442 
3443 /**
3444  * Return the libavcodec license.
3445  */
3446 const char *avcodec_license(void);
3447 
3448 /**
3449  * Register the codec codec and initialize libavcodec.
3450  *
3451  * @warning either this function or avcodec_register_all() must be called
3452  * before any other libavcodec functions.
3453  *
3454  * @see avcodec_register_all()
3455  */
3456 void avcodec_register(AVCodec *codec);
3457 
3458 /**
3459  * Register all the codecs, parsers and bitstream filters which were enabled at
3460  * configuration time. If you do not call this function you can select exactly
3461  * which formats you want to support, by using the individual registration
3462  * functions.
3463  *
3464  * @see avcodec_register
3465  * @see av_register_codec_parser
3466  * @see av_register_bitstream_filter
3467  */
3468 void avcodec_register_all(void);
3469 
3470 /**
3471  * Allocate an AVCodecContext and set its fields to default values. The
3472  * resulting struct should be freed with avcodec_free_context().
3473  *
3474  * @param codec if non-NULL, allocate private data and initialize defaults
3475  * for the given codec. It is illegal to then call avcodec_open2()
3476  * with a different codec.
3477  * If NULL, then the codec-specific defaults won't be initialized,
3478  * which may result in suboptimal default settings (this is
3479  * important mainly for encoders, e.g. libx264).
3480  *
3481  * @return An AVCodecContext filled with default values or NULL on failure.
3482  * @see avcodec_get_context_defaults
3483  */
3485 
3486 /**
3487  * Free the codec context and everything associated with it and write NULL to
3488  * the provided pointer.
3489  */
3490 void avcodec_free_context(AVCodecContext **avctx);
3491 
3492 /**
3493  * Set the fields of the given AVCodecContext to default values corresponding
3494  * to the given codec (defaults may be codec-dependent).
3495  *
3496  * Do not call this function if a non-NULL codec has been passed
3497  * to avcodec_alloc_context3() that allocated this AVCodecContext.
3498  * If codec is non-NULL, it is illegal to call avcodec_open2() with a
3499  * different codec on this AVCodecContext.
3500  */
3502 
3503 /**
3504  * Get the AVClass for AVCodecContext. It can be used in combination with
3505  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3506  *
3507  * @see av_opt_find().
3508  */
3509 const AVClass *avcodec_get_class(void);
3510 
3511 /**
3512  * Get the AVClass for AVFrame. It can be used in combination with
3513  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3514  *
3515  * @see av_opt_find().
3516  */
3517 const AVClass *avcodec_get_frame_class(void);
3518 
3519 /**
3520  * Get the AVClass for AVSubtitleRect. It can be used in combination with
3521  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
3522  *
3523  * @see av_opt_find().
3524  */
3526 
3527 /**
3528  * Copy the settings of the source AVCodecContext into the destination
3529  * AVCodecContext. The resulting destination codec context will be
3530  * unopened, i.e. you are required to call avcodec_open2() before you
3531  * can use this AVCodecContext to decode/encode video/audio data.
3532  *
3533  * @param dest target codec context, should be initialized with
3534  * avcodec_alloc_context3(NULL), but otherwise uninitialized
3535  * @param src source codec context
3536  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
3537  */
3539 
3540 #if FF_API_AVFRAME_LAVC
3541 /**
3542  * @deprecated use av_frame_alloc()
3543  */
3545 AVFrame *avcodec_alloc_frame(void);
3546 
3547 /**
3548  * Set the fields of the given AVFrame to default values.
3549  *
3550  * @param frame The AVFrame of which the fields should be set to default values.
3551  *
3552  * @deprecated use av_frame_unref()
3553  */
3555 void avcodec_get_frame_defaults(AVFrame *frame);
3556 
3557 /**
3558  * Free the frame and any dynamically allocated objects in it,
3559  * e.g. extended_data.
3560  *
3561  * @param frame frame to be freed. The pointer will be set to NULL.
3562  *
3563  * @warning this function does NOT free the data buffers themselves
3564  * (it does not know how, since they might have been allocated with
3565  * a custom get_buffer()).
3566  *
3567  * @deprecated use av_frame_free()
3568  */
3570 void avcodec_free_frame(AVFrame **frame);
3571 #endif
3572 
3573 /**
3574  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
3575  * function the context has to be allocated with avcodec_alloc_context3().
3576  *
3577  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
3578  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
3579  * retrieving a codec.
3580  *
3581  * @warning This function is not thread safe!
3582  *
3583  * @code
3584  * avcodec_register_all();
3585  * av_dict_set(&opts, "b", "2.5M", 0);
3586  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
3587  * if (!codec)
3588  * exit(1);
3589  *
3590  * context = avcodec_alloc_context3(codec);
3591  *
3592  * if (avcodec_open2(context, codec, opts) < 0)
3593  * exit(1);
3594  * @endcode
3595  *
3596  * @param avctx The context to initialize.
3597  * @param codec The codec to open this context for. If a non-NULL codec has been
3598  * previously passed to avcodec_alloc_context3() or
3599  * avcodec_get_context_defaults3() for this context, then this
3600  * parameter MUST be either NULL or equal to the previously passed
3601  * codec.
3602  * @param options A dictionary filled with AVCodecContext and codec-private options.
3603  * On return this object will be filled with options that were not found.
3604  *
3605  * @return zero on success, a negative value on error
3606  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
3607  * av_dict_set(), av_opt_find().
3608  */
3609 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
3610 
3611 /**
3612  * Close a given AVCodecContext and free all the data associated with it
3613  * (but not the AVCodecContext itself).
3614  *
3615  * Calling this function on an AVCodecContext that hasn't been opened will free
3616  * the codec-specific data allocated in avcodec_alloc_context3() /
3617  * avcodec_get_context_defaults3() with a non-NULL codec. Subsequent calls will
3618  * do nothing.
3619  */
3620 int avcodec_close(AVCodecContext *avctx);
3621 
3622 /**
3623  * Free all allocated data in the given subtitle struct.
3624  *
3625  * @param sub AVSubtitle to free.
3626  */
3627 void avsubtitle_free(AVSubtitle *sub);
3628 
3629 /**
3630  * @}
3631  */
3632 
3633 /**
3634  * @addtogroup lavc_packet
3635  * @{
3636  */
3637 
3638 #if FF_API_DESTRUCT_PACKET
3639 /**
3640  * Default packet destructor.
3641  * @deprecated use the AVBuffer API instead
3642  */
3645 #endif
3646 
3647 /**
3648  * Initialize optional fields of a packet with default values.
3649  *
3650  * Note, this does not touch the data and size members, which have to be
3651  * initialized separately.
3652  *
3653  * @param pkt packet
3654  */
3655 void av_init_packet(AVPacket *pkt);
3656 
3657 /**
3658  * Allocate the payload of a packet and initialize its fields with
3659  * default values.
3660  *
3661  * @param pkt packet
3662  * @param size wanted payload size
3663  * @return 0 if OK, AVERROR_xxx otherwise
3664  */
3665 int av_new_packet(AVPacket *pkt, int size);
3666 
3667 /**
3668  * Reduce packet size, correctly zeroing padding
3669  *
3670  * @param pkt packet
3671  * @param size new size
3672  */
3673 void av_shrink_packet(AVPacket *pkt, int size);
3674 
3675 /**
3676  * Increase packet size, correctly zeroing padding
3677  *
3678  * @param pkt packet
3679  * @param grow_by number of bytes by which to increase the size of the packet
3680  */
3681 int av_grow_packet(AVPacket *pkt, int grow_by);
3682 
3683 /**
3684  * Initialize a reference-counted packet from av_malloc()ed data.
3685  *
3686  * @param pkt packet to be initialized. This function will set the data, size,
3687  * buf and destruct fields, all others are left untouched.
3688  * @param data Data allocated by av_malloc() to be used as packet data. If this
3689  * function returns successfully, the data is owned by the underlying AVBuffer.
3690  * The caller may not access the data through other means.
3691  * @param size size of data in bytes, without the padding. I.e. the full buffer
3692  * size is assumed to be size + FF_INPUT_BUFFER_PADDING_SIZE.
3693  *
3694  * @return 0 on success, a negative AVERROR on error
3695  */
3697 
3698 /**
3699  * @warning This is a hack - the packet memory allocation stuff is broken. The
3700  * packet is allocated if it was not really allocated.
3701  */
3702 int av_dup_packet(AVPacket *pkt);
3703 
3704 /**
3705  * Copy packet, including contents
3706  *
3707  * @return 0 on success, negative AVERROR on fail
3708  */
3709 int av_copy_packet(AVPacket *dst, const AVPacket *src);
3710 
3711 /**
3712  * Copy packet side data
3713  *
3714  * @return 0 on success, negative AVERROR on fail
3715  */
3716 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
3717 
3718 /**
3719  * Free a packet.
3720  *
3721  * @param pkt packet to free
3722  */
3723 void av_free_packet(AVPacket *pkt);
3724 
3725 /**
3726  * Allocate new information of a packet.
3727  *
3728  * @param pkt packet
3729  * @param type side information type
3730  * @param size side information size
3731  * @return pointer to fresh allocated data or NULL otherwise
3732  */
3734  int size);
3735 
3736 /**
3737  * Shrink the already allocated side data buffer
3738  *
3739  * @param pkt packet
3740  * @param type side information type
3741  * @param size new side information size
3742  * @return 0 on success, < 0 on failure
3743  */
3745  int size);
3746 
3747 /**
3748  * Get side information from packet.
3749  *
3750  * @param pkt packet
3751  * @param type desired side information type
3752  * @param size pointer for side information size to store (optional)
3753  * @return pointer to data if present or NULL otherwise
3754  */
3756  int *size);
3757 
3759 
3761 
3762 /**
3763  * Pack a dictionary for use in side_data.
3764  *
3765  * @param dict The dictionary to pack.
3766  * @param size pointer to store the size of the returned data
3767  * @return pointer to data if successful, NULL otherwise
3768  */
3770 /**
3771  * Unpack a dictionary from side_data.
3772  *
3773  * @param data data from side_data
3774  * @param size size of the data
3775  * @param dict the metadata storage dictionary
3776  * @return 0 on success, < 0 on failure
3777  */
3778 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
3779 
3780 
3781 /**
3782  * Convenience function to free all the side data stored.
3783  * All the other fields stay untouched.
3784  *
3785  * @param pkt packet
3786  */
3788 
3789 /**
3790  * Setup a new reference to the data described by a given packet
3791  *
3792  * If src is reference-counted, setup dst as a new reference to the
3793  * buffer in src. Otherwise allocate a new buffer in dst and copy the
3794  * data from src into it.
3795  *
3796  * All the other fields are copied from src.
3797  *
3798  * @see av_packet_unref
3799  *
3800  * @param dst Destination packet
3801  * @param src Source packet
3802  *
3803  * @return 0 on success, a negative AVERROR on error.
3804  */
3805 int av_packet_ref(AVPacket *dst, const AVPacket *src);
3806 
3807 /**
3808  * Wipe the packet.
3809  *
3810  * Unreference the buffer referenced by the packet and reset the
3811  * remaining packet fields to their default values.
3812  *
3813  * @param pkt The packet to be unreferenced.
3814  */
3816 
3817 /**
3818  * Move every field in src to dst and reset src.
3819  *
3820  * @see av_packet_unref
3821  *
3822  * @param src Source packet, will be reset
3823  * @param dst Destination packet
3824  */
3826 
3827 /**
3828  * Copy only "properties" fields from src to dst.
3829  *
3830  * Properties for the purpose of this function are all the fields
3831  * beside those related to the packet data (buf, data, size)
3832  *
3833  * @param dst Destination packet
3834  * @param src Source packet
3835  *
3836  * @return 0 on success AVERROR on failure.
3837  *
3838  */
3839 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
3840 
3841 /**
3842  * Convert valid timing fields (timestamps / durations) in a packet from one
3843  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
3844  * ignored.
3845  *
3846  * @param pkt packet on which the conversion will be performed
3847  * @param tb_src source timebase, in which the timing fields in pkt are
3848  * expressed
3849  * @param tb_dst destination timebase, to which the timing fields will be
3850  * converted
3851  */
3852 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
3853 
3854 /**
3855  * @}
3856  */
3857 
3858 /**
3859  * @addtogroup lavc_decoding
3860  * @{
3861  */
3862 
3863 /**
3864  * Find a registered decoder with a matching codec ID.
3865  *
3866  * @param id AVCodecID of the requested decoder
3867  * @return A decoder if one was found, NULL otherwise.
3868  */
3870 
3871 /**
3872  * Find a registered decoder with the specified name.
3873  *
3874  * @param name name of the requested decoder
3875  * @return A decoder if one was found, NULL otherwise.
3876  */
3878 
3879 #if FF_API_GET_BUFFER
3883 #endif
3884 
3885 /**
3886  * The default callback for AVCodecContext.get_buffer2(). It is made public so
3887  * it can be called by custom get_buffer2() implementations for decoders without
3888  * CODEC_CAP_DR1 set.
3889  */
3891 
3892 #if FF_API_EMU_EDGE
3893 /**
3894  * Return the amount of padding in pixels which the get_buffer callback must
3895  * provide around the edge of the image for codecs which do not have the
3896  * CODEC_FLAG_EMU_EDGE flag.
3897  *
3898  * @return Required padding in pixels.
3899  *
3900  * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
3901  * needed
3902  */
3904 unsigned avcodec_get_edge_width(void);
3905 #endif
3906 
3907 /**
3908  * Modify width and height values so that they will result in a memory
3909  * buffer that is acceptable for the codec if you do not use any horizontal
3910  * padding.
3911  *
3912  * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3913  */
3915 
3916 /**
3917  * Modify width and height values so that they will result in a memory
3918  * buffer that is acceptable for the codec if you also ensure that all
3919  * line sizes are a multiple of the respective linesize_align[i].
3920  *
3921  * May only be used if a codec with CODEC_CAP_DR1 has been opened.
3922  */
3924  int linesize_align[AV_NUM_DATA_POINTERS]);
3925 
3926 /**
3927  * Converts AVChromaLocation to swscale x/y chroma position.
3928  *
3929  * The positions represent the chroma (0,0) position in a coordinates system
3930  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3931  *
3932  * @param xpos horizontal chroma sample position
3933  * @param ypos vertical chroma sample position
3934  */
3935 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
3936 
3937 /**
3938  * Converts swscale x/y chroma position to AVChromaLocation.
3939  *
3940  * The positions represent the chroma (0,0) position in a coordinates system
3941  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
3942  *
3943  * @param xpos horizontal chroma sample position
3944  * @param ypos vertical chroma sample position
3945  */
3946 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
3947 
3948 #if FF_API_OLD_DECODE_AUDIO
3949 /**
3950  * Wrapper function which calls avcodec_decode_audio4.
3951  *
3952  * @deprecated Use avcodec_decode_audio4 instead.
3953  *
3954  * Decode the audio frame of size avpkt->size from avpkt->data into samples.
3955  * Some decoders may support multiple frames in a single AVPacket, such
3956  * decoders would then just decode the first frame. In this case,
3957  * avcodec_decode_audio3 has to be called again with an AVPacket that contains
3958  * the remaining data in order to decode the second frame etc.
3959  * If no frame
3960  * could be outputted, frame_size_ptr is zero. Otherwise, it is the
3961  * decompressed frame size in bytes.
3962  *
3963  * @warning You must set frame_size_ptr to the allocated size of the
3964  * output buffer before calling avcodec_decode_audio3().
3965  *
3966  * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
3967  * the actual read bytes because some optimized bitstream readers read 32 or 64
3968  * bits at once and could read over the end.
3969  *
3970  * @warning The end of the input buffer avpkt->data should be set to 0 to ensure that
3971  * no overreading happens for damaged MPEG streams.
3972  *
3973  * @warning You must not provide a custom get_buffer() when using
3974  * avcodec_decode_audio3(). Doing so will override it with
3975  * avcodec_default_get_buffer. Use avcodec_decode_audio4() instead,
3976  * which does allow the application to provide a custom get_buffer().
3977  *
3978  * @note You might have to align the input buffer avpkt->data and output buffer
3979  * samples. The alignment requirements depend on the CPU: On some CPUs it isn't
3980  * necessary at all, on others it won't work at all if not aligned and on others
3981  * it will work but it will have an impact on performance.
3982  *
3983  * In practice, avpkt->data should have 4 byte alignment at minimum and
3984  * samples should be 16 byte aligned unless the CPU doesn't need it
3985  * (AltiVec and SSE do).
3986  *
3987  * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
3988  * between input and output, these need to be fed with avpkt->data=NULL,
3989  * avpkt->size=0 at the end to return the remaining frames.
3990  *
3991  * @param avctx the codec context
3992  * @param[out] samples the output buffer, sample type in avctx->sample_fmt
3993  * If the sample format is planar, each channel plane will
3994  * be the same size, with no padding between channels.
3995  * @param[in,out] frame_size_ptr the output buffer size in bytes
3996  * @param[in] avpkt The input AVPacket containing the input buffer.
3997  * You can create such packet with av_init_packet() and by then setting
3998  * data and size, some decoders might in addition need other fields.
3999  * All decoders are designed to use the least fields possible though.
4000  * @return On error a negative value is returned, otherwise the number of bytes
4001  * used or zero if no frame data was decompressed (used) from the input AVPacket.
4002  */
4003 attribute_deprecated int avcodec_decode_audio3(AVCodecContext *avctx, int16_t *samples,
4004  int *frame_size_ptr,
4005  AVPacket *avpkt);
4006 #endif
4007 
4008 /**
4009  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4010  *
4011  * Some decoders may support multiple frames in a single AVPacket. Such
4012  * decoders would then just decode the first frame and the return value would be
4013  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4014  * called again with an AVPacket containing the remaining data in order to
4015  * decode the second frame, etc... Even if no frames are returned, the packet
4016  * needs to be fed to the decoder with remaining data until it is completely
4017  * consumed or an error occurs.
4018  *
4019  * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
4020  * and output. This means that for some packets they will not immediately
4021  * produce decoded output and need to be flushed at the end of decoding to get
4022  * all the decoded data. Flushing is done by calling this function with packets
4023  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4024  * returning samples. It is safe to flush even those decoders that are not
4025  * marked with CODEC_CAP_DELAY, then no samples will be returned.
4026  *
4027  * @warning The input buffer, avpkt->data must be FF_INPUT_BUFFER_PADDING_SIZE
4028  * larger than the actual read bytes because some optimized bitstream
4029  * readers read 32 or 64 bits at once and could read over the end.
4030  *
4031  * @param avctx the codec context
4032  * @param[out] frame The AVFrame in which to store decoded audio samples.
4033  * The decoder will allocate a buffer for the decoded frame by
4034  * calling the AVCodecContext.get_buffer2() callback.
4035  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4036  * reference counted and the returned reference belongs to the
4037  * caller. The caller must release the frame using av_frame_unref()
4038  * when the frame is no longer needed. The caller may safely write
4039  * to the frame if av_frame_is_writable() returns 1.
4040  * When AVCodecContext.refcounted_frames is set to 0, the returned
4041  * reference belongs to the decoder and is valid only until the
4042  * next call to this function or until closing or flushing the
4043  * decoder. The caller may not write to it.
4044  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4045  * non-zero. Note that this field being set to zero
4046  * does not mean that an error has occurred. For
4047  * decoders with CODEC_CAP_DELAY set, no given decode
4048  * call is guaranteed to produce a frame.
4049  * @param[in] avpkt The input AVPacket containing the input buffer.
4050  * At least avpkt->data and avpkt->size should be set. Some
4051  * decoders might also require additional fields to be set.
4052  * @return A negative error code is returned if an error occurred during
4053  * decoding, otherwise the number of bytes consumed from the input
4054  * AVPacket is returned.
4055  */
4057  int *got_frame_ptr, const AVPacket *avpkt);
4058 
4059 /**
4060  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4061  * Some decoders may support multiple frames in a single AVPacket, such
4062  * decoders would then just decode the first frame.
4063  *
4064  * @warning The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than
4065  * the actual read bytes because some optimized bitstream readers read 32 or 64
4066  * bits at once and could read over the end.
4067  *
4068  * @warning The end of the input buffer buf should be set to 0 to ensure that
4069  * no overreading happens for damaged MPEG streams.
4070  *
4071  * @note Codecs which have the CODEC_CAP_DELAY capability set have a delay
4072  * between input and output, these need to be fed with avpkt->data=NULL,
4073  * avpkt->size=0 at the end to return the remaining frames.
4074  *
4075  * @param avctx the codec context
4076  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4077  * Use av_frame_alloc() to get an AVFrame. The codec will
4078  * allocate memory for the actual bitmap by calling the
4079  * AVCodecContext.get_buffer2() callback.
4080  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4081  * reference counted and the returned reference belongs to the
4082  * caller. The caller must release the frame using av_frame_unref()
4083  * when the frame is no longer needed. The caller may safely write
4084  * to the frame if av_frame_is_writable() returns 1.
4085  * When AVCodecContext.refcounted_frames is set to 0, the returned
4086  * reference belongs to the decoder and is valid only until the
4087  * next call to this function or until closing or flushing the
4088  * decoder. The caller may not write to it.
4089  *
4090  * @param[in] avpkt The input AVPacket containing the input buffer.
4091  * You can create such packet with av_init_packet() and by then setting
4092  * data and size, some decoders might in addition need other fields like
4093  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4094  * fields possible.
4095  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4096  * @return On error a negative value is returned, otherwise the number of bytes
4097  * used or zero if no frame could be decompressed.
4098  */
4099 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4100  int *got_picture_ptr,
4101  const AVPacket *avpkt);
4102 
4103 /**
4104  * Decode a subtitle message.
4105  * Return a negative value on error, otherwise return the number of bytes used.
4106  * If no subtitle could be decompressed, got_sub_ptr is zero.
4107  * Otherwise, the subtitle is stored in *sub.
4108  * Note that CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4109  * simplicity, because the performance difference is expect to be negligible
4110  * and reusing a get_buffer written for video codecs would probably perform badly
4111  * due to a potentially very different allocation pattern.
4112  *
4113  * Some decoders (those marked with CODEC_CAP_DELAY) have a delay between input
4114  * and output. This means that for some packets they will not immediately
4115  * produce decoded output and need to be flushed at the end of decoding to get
4116  * all the decoded data. Flushing is done by calling this function with packets
4117  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4118  * returning subtitles. It is safe to flush even those decoders that are not
4119  * marked with CODEC_CAP_DELAY, then no subtitles will be returned.
4120  *
4121  * @param avctx the codec context
4122  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4123  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4124  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4125  * @param[in] avpkt The input AVPacket containing the input buffer.
4126  */
4128  int *got_sub_ptr,
4129  AVPacket *avpkt);
4130 
4131 /**
4132  * @defgroup lavc_parsing Frame parsing
4133  * @{
4134  */
4138  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
4139  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
4140  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
4141 };
4143 typedef struct AVCodecParserContext {
4144  void *priv_data;
4146  int64_t frame_offset; /* offset of the current frame */
4147  int64_t cur_offset; /* current offset
4148  (incremented by each av_parser_parse()) */
4149  int64_t next_frame_offset; /* offset of the next frame */
4150  /* video info */
4151  int pict_type; /* XXX: Put it back in AVCodecContext. */
4152  /**
4153  * This field is used for proper frame duration computation in lavf.
4154  * It signals, how much longer the frame duration of the current frame
4155  * is compared to normal frame duration.
4156  *
4157  * frame_duration = (1 + repeat_pict) * time_base
4158  *
4159  * It is used by codecs like H.264 to display telecined material.
4160  */
4161  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
4162  int64_t pts; /* pts of the current frame */
4163  int64_t dts; /* dts of the current frame */
4164 
4165  /* private data */
4166  int64_t last_pts;
4167  int64_t last_dts;
4168  int fetch_timestamp;
4170 #define AV_PARSER_PTS_NB 4
4176  int flags;
4177 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
4178 #define PARSER_FLAG_ONCE 0x0002
4179 /// Set if the parser has a valid file offset
4180 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
4181 #define PARSER_FLAG_USE_CODEC_TS 0x1000
4183  int64_t offset; ///< byte offset from starting packet start
4185 
4186  /**
4187  * Set by parser to 1 for key frames and 0 for non-key frames.
4188  * It is initialized to -1, so if the parser doesn't set this flag,
4189  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
4190  * will be used.
4191  */
4192  int key_frame;
4193 
4194  /**
4195  * Time difference in stream time base units from the pts of this
4196  * packet to the point at which the output from the decoder has converged
4197  * independent from the availability of previous frames. That is, the
4198  * frames are virtually identical no matter if decoding started from
4199  * the very first frame or from this keyframe.
4200  * Is AV_NOPTS_VALUE if unknown.
4201  * This field is not the display duration of the current frame.
4202  * This field has no meaning if the packet does not have AV_PKT_FLAG_KEY
4203  * set.
4204  *
4205  * The purpose of this field is to allow seeking in streams that have no
4206  * keyframes in the conventional sense. It corresponds to the
4207  * recovery point SEI in H.264 and match_time_delta in NUT. It is also
4208  * essential for some types of subtitle streams to ensure that all
4209  * subtitles are correctly displayed after seeking.
4210  */
4211  int64_t convergence_duration;
4212 
4213  // Timestamp generation support:
4214  /**
4215  * Synchronization point for start of timestamp generation.
4216  *
4217  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
4218  * (default).
4219  *
4220  * For example, this corresponds to presence of H.264 buffering period
4221  * SEI message.
4222  */
4223  int dts_sync_point;
4224 
4225  /**
4226  * Offset of the current timestamp against last timestamp sync point in
4227  * units of AVCodecContext.time_base.
4228  *
4229  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4230  * contain a valid timestamp offset.
4231  *
4232  * Note that the timestamp of sync point has usually a nonzero
4233  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
4234  * the next frame after timestamp sync point will be usually 1.
4235  *
4236  * For example, this corresponds to H.264 cpb_removal_delay.
4237  */
4238  int dts_ref_dts_delta;
4239 
4240  /**
4241  * Presentation delay of current frame in units of AVCodecContext.time_base.
4242  *
4243  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
4244  * contain valid non-negative timestamp delta (presentation time of a frame
4245  * must not lie in the past).
4246  *
4247  * This delay represents the difference between decoding and presentation
4248  * time of the frame.
4249  *
4250  * For example, this corresponds to H.264 dpb_output_delay.
4251  */
4252  int pts_dts_delta;
4253 
4254  /**
4255  * Position of the packet in file.
4256  *
4257  * Analogous to cur_frame_pts/dts
4258  */
4260 
4261  /**
4262  * Byte position of currently parsed frame in stream.
4263  */
4264  int64_t pos;
4265 
4266  /**
4267  * Previous frame byte position.
4268  */
4269  int64_t last_pos;
4270 
4271  /**
4272  * Duration of the current frame.
4273  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
4274  * For all other types, this is in units of AVCodecContext.time_base.
4275  */
4276  int duration;
4279 
4280  /**
4281  * Indicate whether a picture is coded as a frame, top field or bottom field.
4282  *
4283  * For example, H.264 field_pic_flag equal to 0 corresponds to
4284  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
4285  * equal to 1 and bottom_field_flag equal to 0 corresponds to
4286  * AV_PICTURE_STRUCTURE_TOP_FIELD.
4287  */
4289 
4290  /**
4291  * Picture number incremented in presentation or output order.
4292  * This field may be reinitialized at the first picture of a new sequence.
4293  *
4294  * For example, this corresponds to H.264 PicOrderCnt.
4295  */
4299 typedef struct AVCodecParser {
4300  int codec_ids[5]; /* several codec IDs are permitted */
4304  AVCodecContext *avctx,
4305  const uint8_t **poutbuf, int *poutbuf_size,
4306  const uint8_t *buf, int buf_size);
4308  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
4309  struct AVCodecParser *next;
4310 } AVCodecParser;
4311 
4313 
4316 
4317 /**
4318  * Parse a packet.
4319  *
4320  * @param s parser context.
4321  * @param avctx codec context.
4322  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
4323  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
4324  * @param buf input buffer.
4325  * @param buf_size input length, to signal EOF, this should be 0 (so that the last frame can be output).
4326  * @param pts input presentation timestamp.
4327  * @param dts input decoding timestamp.
4328  * @param pos input byte position in stream.
4329  * @return the number of bytes of the input bitstream used.
4330  *
4331  * Example:
4332  * @code
4333  * while(in_len){
4334  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
4335  * in_data, in_len,
4336  * pts, dts, pos);
4337  * in_data += len;
4338  * in_len -= len;
4339  *
4340  * if(size)
4341  * decode_frame(data, size);
4342  * }
4343  * @endcode
4344  */
4346  AVCodecContext *avctx,
4347  uint8_t **poutbuf, int *poutbuf_size,
4348  const uint8_t *buf, int buf_size,
4349  int64_t pts, int64_t dts,
4350  int64_t pos);
4351 
4352 /**
4353  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
4354  * @deprecated use AVBitStreamFilter
4355  */
4357  AVCodecContext *avctx,
4358  uint8_t **poutbuf, int *poutbuf_size,
4359  const uint8_t *buf, int buf_size, int keyframe);
4361 
4362 /**
4363  * @}
4364  * @}
4365  */
4366 
4367 /**
4368  * @addtogroup lavc_encoding
4369  * @{
4370  */
4371 
4372 /**
4373  * Find a registered encoder with a matching codec ID.
4374  *
4375  * @param id AVCodecID of the requested encoder
4376  * @return An encoder if one was found, NULL otherwise.
4377  */
4379 
4380 /**
4381  * Find a registered encoder with the specified name.
4382  *
4383  * @param name name of the requested encoder
4384  * @return An encoder if one was found, NULL otherwise.
4385  */
4387 
4388 #if FF_API_OLD_ENCODE_AUDIO
4389 /**
4390  * Encode an audio frame from samples into buf.
4391  *
4392  * @deprecated Use avcodec_encode_audio2 instead.
4393  *
4394  * @note The output buffer should be at least FF_MIN_BUFFER_SIZE bytes large.
4395  * However, for codecs with avctx->frame_size equal to 0 (e.g. PCM) the user
4396  * will know how much space is needed because it depends on the value passed
4397  * in buf_size as described below. In that case a lower value can be used.
4398  *
4399  * @param avctx the codec context
4400  * @param[out] buf the output buffer
4401  * @param[in] buf_size the output buffer size
4402  * @param[in] samples the input buffer containing the samples
4403  * The number of samples read from this buffer is frame_size*channels,
4404  * both of which are defined in avctx.
4405  * For codecs which have avctx->frame_size equal to 0 (e.g. PCM) the number of
4406  * samples read from samples is equal to:
4407  * buf_size * 8 / (avctx->channels * av_get_bits_per_sample(avctx->codec_id))
4408  * This also implies that av_get_bits_per_sample() must not return 0 for these
4409  * codecs.
4410  * @return On error a negative value is returned, on success zero or the number
4411  * of bytes used to encode the data read from the input buffer.
4412  */
4414  uint8_t *buf, int buf_size,
4415  const short *samples);
4416 #endif
4417 
4418 /**
4419  * Encode a frame of audio.
4420  *
4421  * Takes input samples from frame and writes the next output packet, if
4422  * available, to avpkt. The output packet does not necessarily contain data for
4423  * the most recent frame, as encoders can delay, split, and combine input frames
4424  * internally as needed.
4425  *
4426  * @param avctx codec context
4427  * @param avpkt output AVPacket.
4428  * The user can supply an output buffer by setting
4429  * avpkt->data and avpkt->size prior to calling the
4430  * function, but if the size of the user-provided data is not
4431  * large enough, encoding will fail. If avpkt->data and
4432  * avpkt->size are set, avpkt->destruct must also be set. All
4433  * other AVPacket fields will be reset by the encoder using
4434  * av_init_packet(). If avpkt->data is NULL, the encoder will
4435  * allocate it. The encoder will set avpkt->size to the size
4436  * of the output packet.
4437  *
4438  * If this function fails or produces no output, avpkt will be
4439  * freed using av_free_packet() (i.e. avpkt->destruct will be
4440  * called to free the user supplied buffer).
4441  * @param[in] frame AVFrame containing the raw audio data to be encoded.
4442  * May be NULL when flushing an encoder that has the
4443  * CODEC_CAP_DELAY capability set.
4444  * If CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4445  * can have any number of samples.
4446  * If it is not set, frame->nb_samples must be equal to
4447  * avctx->frame_size for all frames except the last.
4448  * The final frame may be smaller than avctx->frame_size.
4449  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4450  * output packet is non-empty, and to 0 if it is
4451  * empty. If the function returns an error, the
4452  * packet can be assumed to be invalid, and the
4453  * value of got_packet_ptr is undefined and should
4454  * not be used.
4455  * @return 0 on success, negative error code on failure
4456  */
4457 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
4458  const AVFrame *frame, int *got_packet_ptr);
4459 
4460 #if FF_API_OLD_ENCODE_VIDEO
4461 /**
4462  * @deprecated use avcodec_encode_video2() instead.
4463  *
4464  * Encode a video frame from pict into buf.
4465  * The input picture should be
4466  * stored using a specific format, namely avctx.pix_fmt.
4467  *
4468  * @param avctx the codec context
4469  * @param[out] buf the output buffer for the bitstream of encoded frame
4470  * @param[in] buf_size the size of the output buffer in bytes
4471  * @param[in] pict the input picture to encode
4472  * @return On error a negative value is returned, on success zero or the number
4473  * of bytes used from the output buffer.
4474  */
4476 int avcodec_encode_video(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4477  const AVFrame *pict);
4478 #endif
4479 
4480 /**
4481  * Encode a frame of video.
4482  *
4483  * Takes input raw video data from frame and writes the next output packet, if
4484  * available, to avpkt. The output packet does not necessarily contain data for
4485  * the most recent frame, as encoders can delay and reorder input frames
4486  * internally as needed.
4487  *
4488  * @param avctx codec context
4489  * @param avpkt output AVPacket.
4490  * The user can supply an output buffer by setting
4491  * avpkt->data and avpkt->size prior to calling the
4492  * function, but if the size of the user-provided data is not
4493  * large enough, encoding will fail. All other AVPacket fields
4494  * will be reset by the encoder using av_init_packet(). If
4495  * avpkt->data is NULL, the encoder will allocate it.
4496  * The encoder will set avpkt->size to the size of the
4497  * output packet. The returned data (if any) belongs to the
4498  * caller, he is responsible for freeing it.
4499  *
4500  * If this function fails or produces no output, avpkt will be
4501  * freed using av_free_packet() (i.e. avpkt->destruct will be
4502  * called to free the user supplied buffer).
4503  * @param[in] frame AVFrame containing the raw video data to be encoded.
4504  * May be NULL when flushing an encoder that has the
4505  * CODEC_CAP_DELAY capability set.
4506  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
4507  * output packet is non-empty, and to 0 if it is
4508  * empty. If the function returns an error, the
4509  * packet can be assumed to be invalid, and the
4510  * value of got_packet_ptr is undefined and should
4511  * not be used.
4512  * @return 0 on success, negative error code on failure
4513  */
4514 int avcodec_encode_video2(AVCodecContext *avctx, AVPacket *avpkt,
4515  const AVFrame *frame, int *got_packet_ptr);
4516 
4517 int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
4518  const AVSubtitle *sub);
4519 
4520 
4521 /**
4522  * @}
4523  */
4524 
4525 #if FF_API_AVCODEC_RESAMPLE
4526 /**
4527  * @defgroup lavc_resample Audio resampling
4528  * @ingroup libavc
4529  * @deprecated use libswresample instead
4530  *
4531  * @{
4532  */
4533 struct ReSampleContext;
4534 struct AVResampleContext;
4535 
4536 typedef struct ReSampleContext ReSampleContext;
4537 
4538 /**
4539  * Initialize audio resampling context.
4540  *
4541  * @param output_channels number of output channels
4542  * @param input_channels number of input channels
4543  * @param output_rate output sample rate
4544  * @param input_rate input sample rate
4545  * @param sample_fmt_out requested output sample format
4546  * @param sample_fmt_in input sample format
4547  * @param filter_length length of each FIR filter in the filterbank relative to the cutoff frequency
4548  * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4549  * @param linear if 1 then the used FIR filter will be linearly interpolated
4550  between the 2 closest, if 0 the closest will be used
4551  * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4552  * @return allocated ReSampleContext, NULL if error occurred
4553  */
4556  int output_rate, int input_rate,
4557  enum AVSampleFormat sample_fmt_out,
4558  enum AVSampleFormat sample_fmt_in,
4559  int filter_length, int log2_phase_count,
4560  int linear, double cutoff);
4561 
4563 int audio_resample(ReSampleContext *s, short *output, short *input, int nb_samples);
4564 
4565 /**
4566  * Free resample context.
4567  *
4568  * @param s a non-NULL pointer to a resample context previously
4569  * created with av_audio_resample_init()
4570  */
4573 
4574 
4575 /**
4576  * Initialize an audio resampler.
4577  * Note, if either rate is not an integer then simply scale both rates up so they are.
4578  * @param filter_length length of each FIR filter in the filterbank relative to the cutoff freq
4579  * @param log2_phase_count log2 of the number of entries in the polyphase filterbank
4580  * @param linear If 1 then the used FIR filter will be linearly interpolated
4581  between the 2 closest, if 0 the closest will be used
4582  * @param cutoff cutoff frequency, 1.0 corresponds to half the output sampling rate
4583  */
4585 struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff);
4586 
4587 /**
4588  * Resample an array of samples using a previously configured context.
4589  * @param src an array of unconsumed samples
4590  * @param consumed the number of samples of src which have been consumed are returned here
4591  * @param src_size the number of unconsumed samples available
4592  * @param dst_size the amount of space in samples available in dst
4593  * @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.
4594  * @return the number of samples written in dst or -1 if an error occurred
4595  */
4597 int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx);
4598 
4599 
4600 /**
4601  * Compensate samplerate/timestamp drift. The compensation is done by changing
4602  * the resampler parameters, so no audible clicks or similar distortions occur
4603  * @param compensation_distance distance in output samples over which the compensation should be performed
4604  * @param sample_delta number of output samples which should be output less
4605  *
4606  * example: av_resample_compensate(c, 10, 500)
4607  * here instead of 510 samples only 500 samples would be output
4608  *
4609  * note, due to rounding the actual compensation might be slightly different,
4610  * especially if the compensation_distance is large and the in_rate used during init is small
4611  */
4613 void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance);
4615 void av_resample_close(struct AVResampleContext *c);
4616 
4617 /**
4618  * @}
4619  */
4620 #endif
4621 
4622 /**
4623  * @addtogroup lavc_picture
4624  * @{
4625  */
4626 
4627 /**
4628  * Allocate memory for the pixels of a picture and setup the AVPicture
4629  * fields for it.
4630  *
4631  * Call avpicture_free() to free it.
4632  *
4633  * @param picture the picture structure to be filled in
4634  * @param pix_fmt the pixel format of the picture
4635  * @param width the width of the picture
4636  * @param height the height of the picture
4637  * @return zero if successful, a negative error code otherwise
4638  *
4639  * @see av_image_alloc(), avpicture_fill()
4640  */
4641 int avpicture_alloc(AVPicture *picture, enum AVPixelFormat pix_fmt, int width, int height);
4642 
4643 /**
4644  * Free a picture previously allocated by avpicture_alloc().
4645  * The data buffer used by the AVPicture is freed, but the AVPicture structure
4646  * itself is not.
4647  *
4648  * @param picture the AVPicture to be freed
4649  */
4650 void avpicture_free(AVPicture *picture);
4651 
4652 /**
4653  * Setup the picture fields based on the specified image parameters
4654  * and the provided image data buffer.
4655  *
4656  * The picture fields are filled in by using the image data buffer
4657  * pointed to by ptr.
4658  *
4659  * If ptr is NULL, the function will fill only the picture linesize
4660  * array and return the required size for the image buffer.
4661  *
4662  * To allocate an image buffer and fill the picture data in one call,
4663  * use avpicture_alloc().
4664  *
4665  * @param picture the picture to be filled in
4666  * @param ptr buffer where the image data is stored, or NULL
4667  * @param pix_fmt the pixel format of the image
4668  * @param width the width of the image in pixels
4669  * @param height the height of the image in pixels
4670  * @return the size in bytes required for src, a negative error code
4671  * in case of failure
4672  *
4673  * @see av_image_fill_arrays()
4674  */
4675 int avpicture_fill(AVPicture *picture, const uint8_t *ptr,
4676  enum AVPixelFormat pix_fmt, int width, int height);
4677 
4678 /**
4679  * Copy pixel data from an AVPicture into a buffer.
4680  *
4681  * avpicture_get_size() can be used to compute the required size for
4682  * the buffer to fill.
4683  *
4684  * @param src source picture with filled data
4685  * @param pix_fmt picture pixel format
4686  * @param width picture width
4687  * @param height picture height
4688  * @param dest destination buffer
4689  * @param dest_size destination buffer size in bytes
4690  * @return the number of bytes written to dest, or a negative value
4691  * (error code) on error, for example if the destination buffer is not
4692  * big enough
4693  *
4694  * @see av_image_copy_to_buffer()
4695  */
4697  int width, int height,
4698  unsigned char *dest, int dest_size);
4699 
4700 /**
4701  * Calculate the size in bytes that a picture of the given width and height
4702  * would occupy if stored in the given picture format.
4703  *
4704  * @param pix_fmt picture pixel format
4705  * @param width picture width
4706  * @param height picture height
4707  * @return the computed picture buffer size or a negative error code
4708  * in case of error
4709  *
4710  * @see av_image_get_buffer_size().
4711  */
4713 
4714 #if FF_API_DEINTERLACE
4715 /**
4716  * deinterlace - if not supported return -1
4717  *
4718  * @deprecated - use yadif (in libavfilter) instead
4719  */
4721 int avpicture_deinterlace(AVPicture *dst, const AVPicture *src,
4722  enum AVPixelFormat pix_fmt, int width, int height);
4723 #endif
4724 /**
4725  * Copy image src to dst. Wraps av_image_copy().
4726  */
4727 void av_picture_copy(AVPicture *dst, const AVPicture *src,
4728  enum AVPixelFormat pix_fmt, int width, int height);
4729 
4730 /**
4731  * Crop image top and left side.
4732  */
4733 int av_picture_crop(AVPicture *dst, const AVPicture *src,
4734  enum AVPixelFormat pix_fmt, int top_band, int left_band);
4735 
4736 /**
4737  * Pad image.
4738  */
4739 int av_picture_pad(AVPicture *dst, const AVPicture *src, int height, int width, enum AVPixelFormat pix_fmt,
4740  int padtop, int padbottom, int padleft, int padright, int *color);
4741 
4742 /**
4743  * @}
4744  */
4745 
4746 /**
4747  * @defgroup lavc_misc Utility functions
4748  * @ingroup libavc
4749  *
4750  * Miscellaneous utility functions related to both encoding and decoding
4751  * (or neither).
4752  * @{
4753  */
4754 
4755 /**
4756  * @defgroup lavc_misc_pixfmt Pixel formats
4757  *
4758  * Functions for working with pixel formats.
4759  * @{
4760  */
4761 
4762 /**
4763  * Utility function to access log2_chroma_w log2_chroma_h from
4764  * the pixel format AVPixFmtDescriptor.
4765  *
4766  * This function asserts that pix_fmt is valid. See av_pix_fmt_get_chroma_sub_sample
4767  * for one that returns a failure code and continues in case of invalid
4768  * pix_fmts.
4769  *
4770  * @param[in] pix_fmt the pixel format
4771  * @param[out] h_shift store log2_chroma_w
4772  * @param[out] v_shift store log2_chroma_h
4773  *
4774  * @see av_pix_fmt_get_chroma_sub_sample
4775  */
4776 
4777 void avcodec_get_chroma_sub_sample(enum AVPixelFormat pix_fmt, int *h_shift, int *v_shift);
4778 
4779 /**
4780  * Return a value representing the fourCC code associated to the
4781  * pixel format pix_fmt, or 0 if no associated fourCC code can be
4782  * found.
4783  */
4785 
4786 /**
4787  * @deprecated see av_get_pix_fmt_loss()
4788  */
4789 int avcodec_get_pix_fmt_loss(enum AVPixelFormat dst_pix_fmt, enum AVPixelFormat src_pix_fmt,
4790  int has_alpha);
4791 
4792 /**
4793  * Find the best pixel format to convert to given a certain source pixel
4794  * format. When converting from one pixel format to another, information loss
4795  * may occur. For example, when converting from RGB24 to GRAY, the color
4796  * information will be lost. Similarly, other losses occur when converting from
4797  * some formats to other formats. avcodec_find_best_pix_fmt_of_2() searches which of
4798  * the given pixel formats should be used to suffer the least amount of loss.
4799  * The pixel formats from which it chooses one, are determined by the
4800  * pix_fmt_list parameter.
4801  *
4802  *
4803  * @param[in] pix_fmt_list AV_PIX_FMT_NONE terminated array of pixel formats to choose from
4804  * @param[in] src_pix_fmt source pixel format
4805  * @param[in] has_alpha Whether the source pixel format alpha channel is used.
4806  * @param[out] loss_ptr Combination of flags informing you what kind of losses will occur.
4807  * @return The best pixel format to convert to or -1 if none was found.
4808  */
4809 enum AVPixelFormat avcodec_find_best_pix_fmt_of_list(const enum AVPixelFormat *pix_fmt_list,
4810  enum AVPixelFormat src_pix_fmt,
4811  int has_alpha, int *loss_ptr);
4812 
4813 /**
4814  * @deprecated see av_find_best_pix_fmt_of_2()
4815  */
4816 enum AVPixelFormat avcodec_find_best_pix_fmt_of_2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4817  enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4818 
4820 #if AV_HAVE_INCOMPATIBLE_LIBAV_ABI
4821 enum AVPixelFormat avcodec_find_best_pix_fmt2(const enum AVPixelFormat *pix_fmt_list,
4822  enum AVPixelFormat src_pix_fmt,
4823  int has_alpha, int *loss_ptr);
4824 #else
4825 enum AVPixelFormat avcodec_find_best_pix_fmt2(enum AVPixelFormat dst_pix_fmt1, enum AVPixelFormat dst_pix_fmt2,
4826  enum AVPixelFormat src_pix_fmt, int has_alpha, int *loss_ptr);
4827 #endif
4828 
4829