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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 /**
46  * @defgroup libavc libavcodec
47  * Encoding/Decoding Library
48  *
49  * @{
50  *
51  * @defgroup lavc_decoding Decoding
52  * @{
53  * @}
54  *
55  * @defgroup lavc_encoding Encoding
56  * @{
57  * @}
58  *
59  * @defgroup lavc_codec Codecs
60  * @{
61  * @defgroup lavc_codec_native Native Codecs
62  * @{
63  * @}
64  * @defgroup lavc_codec_wrappers External library wrappers
65  * @{
66  * @}
67  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
68  * @{
69  * @}
70  * @}
71  * @defgroup lavc_internal Internal
72  * @{
73  * @}
74  * @}
75  */
76 
77 /**
78  * @ingroup libavc
79  * @defgroup lavc_encdec send/receive encoding and decoding API overview
80  * @{
81  *
82  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
83  * avcodec_receive_packet() functions provide an encode/decode API, which
84  * decouples input and output.
85  *
86  * The API is very similar for encoding/decoding and audio/video, and works as
87  * follows:
88  * - Set up and open the AVCodecContext as usual.
89  * - Send valid input:
90  * - For decoding, call avcodec_send_packet() to give the decoder raw
91  * compressed data in an AVPacket.
92  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
93  * containing uncompressed audio or video.
94  * In both cases, it is recommended that AVPackets and AVFrames are
95  * refcounted, or libavcodec might have to copy the input data. (libavformat
96  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
97  * refcounted AVFrames.)
98  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
99  * functions and process their output:
100  * - For decoding, call avcodec_receive_frame(). On success, it will return
101  * an AVFrame containing uncompressed audio or video data.
102  * - For encoding, call avcodec_receive_packet(). On success, it will return
103  * an AVPacket with a compressed frame.
104  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
105  * AVERROR(EAGAIN) return value means that new input data is required to
106  * return new output. In this case, continue with sending input. For each
107  * input frame/packet, the codec will typically return 1 output frame/packet,
108  * but it can also be 0 or more than 1.
109  *
110  * At the beginning of decoding or encoding, the codec might accept multiple
111  * input frames/packets without returning a frame, until its internal buffers
112  * are filled. This situation is handled transparently if you follow the steps
113  * outlined above.
114  *
115  * In theory, sending input can result in EAGAIN - this should happen only if
116  * not all output was received. You can use this to structure alternative decode
117  * or encode loops other than the one suggested above. For example, you could
118  * try sending new input on each iteration, and try to receive output if that
119  * returns EAGAIN.
120  *
121  * End of stream situations. These require "flushing" (aka draining) the codec,
122  * as the codec might buffer multiple frames or packets internally for
123  * performance or out of necessity (consider B-frames).
124  * This is handled as follows:
125  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
126  * or avcodec_send_frame() (encoding) functions. This will enter draining
127  * mode.
128  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
129  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
130  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
131  * - Before decoding can be resumed again, the codec has to be reset with
132  * avcodec_flush_buffers().
133  *
134  * Using the API as outlined above is highly recommended. But it is also
135  * possible to call functions outside of this rigid schema. For example, you can
136  * call avcodec_send_packet() repeatedly without calling
137  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
138  * until the codec's internal buffer has been filled up (which is typically of
139  * size 1 per output frame, after initial input), and then reject input with
140  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
141  * read at least some output.
142  *
143  * Not all codecs will follow a rigid and predictable dataflow; the only
144  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
145  * one end implies that a receive/send call on the other end will succeed, or
146  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
147  * permit unlimited buffering of input or output.
148  *
149  * This API replaces the following legacy functions:
150  * - avcodec_decode_video2() and avcodec_decode_audio4():
151  * Use avcodec_send_packet() to feed input to the decoder, then use
152  * avcodec_receive_frame() to receive decoded frames after each packet.
153  * Unlike with the old video decoding API, multiple frames might result from
154  * a packet. For audio, splitting the input packet into frames by partially
155  * decoding packets becomes transparent to the API user. You never need to
156  * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
157  * no data was read from the packet).
158  * Additionally, sending a flush/draining packet is required only once.
159  * - avcodec_encode_video2()/avcodec_encode_audio2():
160  * Use avcodec_send_frame() to feed input to the encoder, then use
161  * avcodec_receive_packet() to receive encoded packets.
162  * Providing user-allocated buffers for avcodec_receive_packet() is not
163  * possible.
164  * - The new API does not handle subtitles yet.
165  *
166  * Mixing new and old function calls on the same AVCodecContext is not allowed,
167  * and will result in undefined behavior.
168  *
169  * Some codecs might require using the new API; using the old API will return
170  * an error when calling it. All codecs support the new API.
171  *
172  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
173  * would be an invalid state, which could put the codec user into an endless
174  * loop. The API has no concept of time either: it cannot happen that trying to
175  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
176  * later accepts the packet (with no other receive/flush API calls involved).
177  * The API is a strict state machine, and the passage of time is not supposed
178  * to influence it. Some timing-dependent behavior might still be deemed
179  * acceptable in certain cases. But it must never result in both send/receive
180  * returning EAGAIN at the same time at any point. It must also absolutely be
181  * avoided that the current state is "unstable" and can "flip-flop" between
182  * the send/receive APIs allowing progress. For example, it's not allowed that
183  * the codec randomly decides that it actually wants to consume a packet now
184  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
185  * avcodec_send_packet() call.
186  * @}
187  */
188 
189 /**
190  * @defgroup lavc_core Core functions/structures.
191  * @ingroup libavc
192  *
193  * Basic definitions, functions for querying libavcodec capabilities,
194  * allocating core structures, etc.
195  * @{
196  */
197 
198 
199 /**
200  * Identify the syntax and semantics of the bitstream.
201  * The principle is roughly:
202  * Two decoders with the same ID can decode the same streams.
203  * Two encoders with the same ID can encode compatible streams.
204  * There may be slight deviations from the principle due to implementation
205  * details.
206  *
207  * If you add a codec ID to this list, add it so that
208  * 1. no value of an existing codec ID changes (that would break ABI),
209  * 2. it is as close as possible to similar codecs
210  *
211  * After adding new codec IDs, do not forget to add an entry to the codec
212  * descriptor list and bump libavcodec minor version.
213  */
214 enum AVCodecID {
216 
217  /* video codecs */
219  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
220 #if FF_API_XVMC
221  AV_CODEC_ID_MPEG2VIDEO_XVMC,
222 #endif /* FF_API_XVMC */
357 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
395 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
414 
451 
452  /* various PCM "codecs" */
453  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
485 
490 
491  /* various ADPCM codecs */
523 #if FF_API_VIMA_DECODER
525 #endif
526 
537 
538  /* AMR */
541 
542  /* RealAudio codecs*/
545 
546  /* various DPCM codecs */
551 
554 
555  /* audio codecs */
556  AV_CODEC_ID_MP2 = 0x15000,
557  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
574  AV_CODEC_ID_GSM, ///< as in Berlin toast format
586  AV_CODEC_ID_GSM_MS, /* as found in WAV */
588 #if FF_API_VOXWARE
590 #endif
626 
644 
645  /* subtitle codecs */
646  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
649  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
656 
672 
673  /* other specific kind of codecs (generally used for attachments) */
674  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
675  AV_CODEC_ID_TTF = 0x18000,
676 
677  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
686 
687 
688  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
689 
690  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
691  * stream (only used by libavformat) */
692  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
693  * stream (only used by libavformat) */
694  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
695  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
696 };
697 
698 /**
699  * This struct describes the properties of a single codec described by an
700  * AVCodecID.
701  * @see avcodec_descriptor_get()
702  */
703 typedef struct AVCodecDescriptor {
704  enum AVCodecID id;
706  /**
707  * Name of the codec described by this descriptor. It is non-empty and
708  * unique for each codec descriptor. It should contain alphanumeric
709  * characters and '_' only.
710  */
711  const char *name;
712  /**
713  * A more descriptive name for this codec. May be NULL.
714  */
715  const char *long_name;
716  /**
717  * Codec properties, a combination of AV_CODEC_PROP_* flags.
718  */
719  int props;
720  /**
721  * MIME type(s) associated with the codec.
722  * May be NULL; if not, a NULL-terminated array of MIME types.
723  * The first item is always non-NULL and is the preferred MIME type.
724  */
725  const char *const *mime_types;
726  /**
727  * If non-NULL, an array of profiles recognized for this codec.
728  * Terminated with FF_PROFILE_UNKNOWN.
729  */
730  const struct AVProfile *profiles;
732 
733 /**
734  * Codec uses only intra compression.
735  * Video and audio codecs only.
736  */
737 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
738 /**
739  * Codec supports lossy compression. Audio and video codecs only.
740  * @note a codec may support both lossy and lossless
741  * compression modes
742  */
743 #define AV_CODEC_PROP_LOSSY (1 << 1)
744 /**
745  * Codec supports lossless compression. Audio and video codecs only.
746  */
747 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
748 /**
749  * Codec supports frame reordering. That is, the coded order (the order in which
750  * the encoded packets are output by the encoders / stored / input to the
751  * decoders) may be different from the presentation order of the corresponding
752  * frames.
753  *
754  * For codecs that do not have this property set, PTS and DTS should always be
755  * equal.
756  */
757 #define AV_CODEC_PROP_REORDER (1 << 3)
758 /**
759  * Subtitle codec is bitmap based
760  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
761  */
762 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
763 /**
764  * Subtitle codec is text based.
765  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
766  */
767 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
768 
769 /**
770  * @ingroup lavc_decoding
771  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
772  * This is mainly needed because some optimized bitstream readers read
773  * 32 or 64 bit at once and could read over the end.<br>
774  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
775  * MPEG bitstreams could cause overread and segfault.
776  */
777 #define AV_INPUT_BUFFER_PADDING_SIZE 32
778 
779 /**
780  * @ingroup lavc_encoding
781  * minimum encoding buffer size
782  * Used to avoid some checks during header writing.
783  */
784 #define AV_INPUT_BUFFER_MIN_SIZE 16384
785 
786 #if FF_API_WITHOUT_PREFIX
787 /**
788  * @deprecated use AV_INPUT_BUFFER_PADDING_SIZE instead
789  */
790 #define FF_INPUT_BUFFER_PADDING_SIZE 32
791 
792 /**
793  * @deprecated use AV_INPUT_BUFFER_MIN_SIZE instead
794  */
795 #define FF_MIN_BUFFER_SIZE 16384
796 #endif /* FF_API_WITHOUT_PREFIX */
797 
798 /**
799  * @ingroup lavc_encoding
800  * motion estimation type.
801  * @deprecated use codec private option instead
802  */
803 #if FF_API_MOTION_EST
805  ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
809  ME_EPZS, ///< enhanced predictive zonal search
810  ME_X1, ///< reserved for experiments
811  ME_HEX, ///< hexagon based search
812  ME_UMH, ///< uneven multi-hexagon search
813  ME_TESA, ///< transformed exhaustive search algorithm
814  ME_ITER=50, ///< iterative search
815 };
816 #endif
817 
818 /**
819  * @ingroup lavc_decoding
820  */
822  /* We leave some space between them for extensions (drop some
823  * keyframes for intra-only or drop just some bidir frames). */
824  AVDISCARD_NONE =-16, ///< discard nothing
825  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
826  AVDISCARD_NONREF = 8, ///< discard all non reference
827  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
828  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
829  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
830  AVDISCARD_ALL = 48, ///< discard all
831 };
832 
843  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
844 };
845 
846 /**
847  * @ingroup lavc_encoding
848  */
849 typedef struct RcOverride{
852  int qscale; // If this is 0 then quality_factor will be used instead.
854 } RcOverride;
855 
856 #if FF_API_MAX_BFRAMES
857 /**
858  * @deprecated there is no libavcodec-wide limit on the number of B-frames
859  */
860 #define FF_MAX_B_FRAMES 16
861 #endif
862 
863 /* encoding support
864  These flags can be passed in AVCodecContext.flags before initialization.
865  Note: Not everything is supported yet.
866 */
867 
868 /**
869  * Allow decoders to produce frames with data planes that are not aligned
870  * to CPU requirements (e.g. due to cropping).
871  */
872 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
873 /**
874  * Use fixed qscale.
875  */
876 #define AV_CODEC_FLAG_QSCALE (1 << 1)
877 /**
878  * 4 MV per MB allowed / advanced prediction for H.263.
879  */
880 #define AV_CODEC_FLAG_4MV (1 << 2)
881 /**
882  * Output even those frames that might be corrupted.
883  */
884 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
885 /**
886  * Use qpel MC.
887  */
888 #define AV_CODEC_FLAG_QPEL (1 << 4)
889 /**
890  * Use internal 2pass ratecontrol in first pass mode.
891  */
892 #define AV_CODEC_FLAG_PASS1 (1 << 9)
893 /**
894  * Use internal 2pass ratecontrol in second pass mode.
895  */
896 #define AV_CODEC_FLAG_PASS2 (1 << 10)
897 /**
898  * loop filter.
899  */
900 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
901 /**
902  * Only decode/encode grayscale.
903  */
904 #define AV_CODEC_FLAG_GRAY (1 << 13)
905 /**
906  * error[?] variables will be set during encoding.
907  */
908 #define AV_CODEC_FLAG_PSNR (1 << 15)
909 /**
910  * Input bitstream might be truncated at a random location
911  * instead of only at frame boundaries.
912  */
913 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
914 /**
915  * Use interlaced DCT.
916  */
917 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
918 /**
919  * Force low delay.
920  */
921 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
922 /**
923  * Place global headers in extradata instead of every keyframe.
924  */
925 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
926 /**
927  * Use only bitexact stuff (except (I)DCT).
928  */
929 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
930 /* Fx : Flag for H.263+ extra options */
931 /**
932  * H.263 advanced intra coding / MPEG-4 AC prediction
933  */
934 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
935 /**
936  * interlaced motion estimation
937  */
938 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
939 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
940 
941 /**
942  * Allow non spec compliant speedup tricks.
943  */
944 #define AV_CODEC_FLAG2_FAST (1 << 0)
945 /**
946  * Skip bitstream encoding.
947  */
948 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
949 /**
950  * Place global headers at every keyframe instead of in extradata.
951  */
952 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
953 
954 /**
955  * timecode is in drop frame format. DEPRECATED!!!!
956  */
957 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
958 
959 /**
960  * Input bitstream might be truncated at a packet boundaries
961  * instead of only at frame boundaries.
962  */
963 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
964 /**
965  * Discard cropping information from SPS.
966  */
967 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
968 
969 /**
970  * Show all frames before the first keyframe
971  */
972 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
973 /**
974  * Export motion vectors through frame side data
975  */
976 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
977 /**
978  * Do not skip samples and export skip information as frame side data
979  */
980 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
981 /**
982  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
983  */
984 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
985 
986 /* Unsupported options :
987  * Syntax Arithmetic coding (SAC)
988  * Reference Picture Selection
989  * Independent Segment Decoding */
990 /* /Fx */
991 /* codec capabilities */
992 
993 /**
994  * Decoder can use draw_horiz_band callback.
995  */
996 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
997 /**
998  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
999  * If not set, it might not use get_buffer() at all or use operations that
1000  * assume the buffer was allocated by avcodec_default_get_buffer.
1001  */
1002 #define AV_CODEC_CAP_DR1 (1 << 1)
1003 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
1004 /**
1005  * Encoder or decoder requires flushing with NULL input at the end in order to
1006  * give the complete and correct output.
1007  *
1008  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
1009  * with NULL data. The user can still send NULL data to the public encode
1010  * or decode function, but libavcodec will not pass it along to the codec
1011  * unless this flag is set.
1012  *
1013  * Decoders:
1014  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
1015  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
1016  * returns frames.
1017  *
1018  * Encoders:
1019  * The encoder needs to be fed with NULL data at the end of encoding until the
1020  * encoder no longer returns data.
1021  *
1022  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1023  * flag also means that the encoder must set the pts and duration for
1024  * each output packet. If this flag is not set, the pts and duration will
1025  * be determined by libavcodec from the input frame.
1026  */
1027 #define AV_CODEC_CAP_DELAY (1 << 5)
1028 /**
1029  * Codec can be fed a final frame with a smaller size.
1030  * This can be used to prevent truncation of the last audio samples.
1031  */
1032 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
1033 
1034 #if FF_API_CAP_VDPAU
1035 /**
1036  * Codec can export data for HW decoding (VDPAU).
1037  */
1038 #define AV_CODEC_CAP_HWACCEL_VDPAU (1 << 7)
1039 #endif
1040 
1041 /**
1042  * Codec can output multiple frames per AVPacket
1043  * Normally demuxers return one frame at a time, demuxers which do not do
1044  * are connected to a parser to split what they return into proper frames.
1045  * This flag is reserved to the very rare category of codecs which have a
1046  * bitstream that cannot be split into frames without timeconsuming
1047  * operations like full decoding. Demuxers carrying such bitstreams thus
1048  * may return multiple frames in a packet. This has many disadvantages like
1049  * prohibiting stream copy in many cases thus it should only be considered
1050  * as a last resort.
1051  */
1052 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1053 /**
1054  * Codec is experimental and is thus avoided in favor of non experimental
1055  * encoders
1056  */
1057 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1058 /**
1059  * Codec should fill in channel configuration and samplerate instead of container
1060  */
1061 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1062 /**
1063  * Codec supports frame-level multithreading.
1064  */
1065 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1066 /**
1067  * Codec supports slice-based (or partition-based) multithreading.
1068  */
1069 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1070 /**
1071  * Codec supports changed parameters at any point.
1072  */
1073 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1074 /**
1075  * Codec supports avctx->thread_count == 0 (auto).
1076  */
1077 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1078 /**
1079  * Audio encoder supports receiving a different number of samples in each call.
1080  */
1081 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1082 /**
1083  * Decoder is not a preferred choice for probing.
1084  * This indicates that the decoder is not a good choice for probing.
1085  * It could for example be an expensive to spin up hardware decoder,
1086  * or it could simply not provide a lot of useful information about
1087  * the stream.
1088  * A decoder marked with this flag should only be used as last resort
1089  * choice for probing.
1090  */
1091 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1092 /**
1093  * Codec is intra only.
1094  */
1095 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1096 /**
1097  * Codec is lossless.
1098  */
1099 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1100 
1101 
1102 #if FF_API_WITHOUT_PREFIX
1103 /**
1104  * Allow decoders to produce frames with data planes that are not aligned
1105  * to CPU requirements (e.g. due to cropping).
1106  */
1107 #define CODEC_FLAG_UNALIGNED AV_CODEC_FLAG_UNALIGNED
1108 #define CODEC_FLAG_QSCALE AV_CODEC_FLAG_QSCALE
1109 #define CODEC_FLAG_4MV AV_CODEC_FLAG_4MV
1110 #define CODEC_FLAG_OUTPUT_CORRUPT AV_CODEC_FLAG_OUTPUT_CORRUPT
1111 #define CODEC_FLAG_QPEL AV_CODEC_FLAG_QPEL
1112 #if FF_API_GMC
1113 /**
1114  * @deprecated use the "gmc" private option of the libxvid encoder
1115  */
1116 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
1117 #endif
1118 #if FF_API_MV0
1119 /**
1120  * @deprecated use the flag "mv0" in the "mpv_flags" private option of the
1121  * mpegvideo encoders
1122  */
1123 #define CODEC_FLAG_MV0 0x0040
1124 #endif
1125 #if FF_API_INPUT_PRESERVED
1126 /**
1127  * @deprecated passing reference-counted frames to the encoders replaces this
1128  * flag
1129  */
1130 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
1131 #endif
1132 #define CODEC_FLAG_PASS1 AV_CODEC_FLAG_PASS1
1133 #define CODEC_FLAG_PASS2 AV_CODEC_FLAG_PASS2
1134 #define CODEC_FLAG_GRAY AV_CODEC_FLAG_GRAY
1135 #if FF_API_EMU_EDGE
1136 /**
1137  * @deprecated edges are not used/required anymore. I.e. this flag is now always
1138  * set.
1139  */
1140 #define CODEC_FLAG_EMU_EDGE 0x4000
1141 #endif
1142 #define CODEC_FLAG_PSNR AV_CODEC_FLAG_PSNR
1143 #define CODEC_FLAG_TRUNCATED AV_CODEC_FLAG_TRUNCATED
1144 
1145 #if FF_API_NORMALIZE_AQP
1146 /**
1147  * @deprecated use the flag "naq" in the "mpv_flags" private option of the
1148  * mpegvideo encoders
1149  */
1150 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000
1151 #endif
1152 #define CODEC_FLAG_INTERLACED_DCT AV_CODEC_FLAG_INTERLACED_DCT
1153 #define CODEC_FLAG_LOW_DELAY AV_CODEC_FLAG_LOW_DELAY
1154 #define CODEC_FLAG_GLOBAL_HEADER AV_CODEC_FLAG_GLOBAL_HEADER
1155 #define CODEC_FLAG_BITEXACT AV_CODEC_FLAG_BITEXACT
1156 #define CODEC_FLAG_AC_PRED AV_CODEC_FLAG_AC_PRED
1157 #define CODEC_FLAG_LOOP_FILTER AV_CODEC_FLAG_LOOP_FILTER
1158 #define CODEC_FLAG_INTERLACED_ME AV_CODEC_FLAG_INTERLACED_ME
1159 #define CODEC_FLAG_CLOSED_GOP AV_CODEC_FLAG_CLOSED_GOP
1160 #define CODEC_FLAG2_FAST AV_CODEC_FLAG2_FAST
1161 #define CODEC_FLAG2_NO_OUTPUT AV_CODEC_FLAG2_NO_OUTPUT
1162 #define CODEC_FLAG2_LOCAL_HEADER AV_CODEC_FLAG2_LOCAL_HEADER
1163 #define CODEC_FLAG2_DROP_FRAME_TIMECODE AV_CODEC_FLAG2_DROP_FRAME_TIMECODE
1164 #define CODEC_FLAG2_IGNORE_CROP AV_CODEC_FLAG2_IGNORE_CROP
1165 
1166 #define CODEC_FLAG2_CHUNKS AV_CODEC_FLAG2_CHUNKS
1167 #define CODEC_FLAG2_SHOW_ALL AV_CODEC_FLAG2_SHOW_ALL
1168 #define CODEC_FLAG2_EXPORT_MVS AV_CODEC_FLAG2_EXPORT_MVS
1169 #define CODEC_FLAG2_SKIP_MANUAL AV_CODEC_FLAG2_SKIP_MANUAL
1170 
1171 /* Unsupported options :
1172  * Syntax Arithmetic coding (SAC)
1173  * Reference Picture Selection
1174  * Independent Segment Decoding */
1175 /* /Fx */
1176 /* codec capabilities */
1177 
1178 #define CODEC_CAP_DRAW_HORIZ_BAND AV_CODEC_CAP_DRAW_HORIZ_BAND ///< Decoder can use draw_horiz_band callback.
1179 /**
1180  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
1181  * If not set, it might not use get_buffer() at all or use operations that
1182  * assume the buffer was allocated by avcodec_default_get_buffer.
1183  */
1184 #define CODEC_CAP_DR1 AV_CODEC_CAP_DR1
1185 #define CODEC_CAP_TRUNCATED AV_CODEC_CAP_TRUNCATED
1186 #if FF_API_XVMC
1187 /* Codec can export data for HW decoding. This flag indicates that
1188  * the codec would call get_format() with list that might contain HW accelerated
1189  * pixel formats (XvMC, VDPAU, VAAPI, etc). The application can pick any of them
1190  * including raw image format.
1191  * The application can use the passed context to determine bitstream version,
1192  * chroma format, resolution etc.
1193  */
1194 #define CODEC_CAP_HWACCEL 0x0010
1195 #endif /* FF_API_XVMC */
1196 /**
1197  * Encoder or decoder requires flushing with NULL input at the end in order to
1198  * give the complete and correct output.
1199  *
1200  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
1201  * with NULL data. The user can still send NULL data to the public encode
1202  * or decode function, but libavcodec will not pass it along to the codec
1203  * unless this flag is set.
1204  *
1205  * Decoders:
1206  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
1207  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
1208  * returns frames.
1209  *
1210  * Encoders:
1211  * The encoder needs to be fed with NULL data at the end of encoding until the
1212  * encoder no longer returns data.
1213  *
1214  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1215  * flag also means that the encoder must set the pts and duration for
1216  * each output packet. If this flag is not set, the pts and duration will
1217  * be determined by libavcodec from the input frame.
1218  */
1219 #define CODEC_CAP_DELAY AV_CODEC_CAP_DELAY
1220 /**
1221  * Codec can be fed a final frame with a smaller size.
1222  * This can be used to prevent truncation of the last audio samples.
1223  */
1224 #define CODEC_CAP_SMALL_LAST_FRAME AV_CODEC_CAP_SMALL_LAST_FRAME
1225 #if FF_API_CAP_VDPAU
1226 /**
1227  * Codec can export data for HW decoding (VDPAU).
1228  */
1229 #define CODEC_CAP_HWACCEL_VDPAU AV_CODEC_CAP_HWACCEL_VDPAU
1230 #endif
1231 /**
1232  * Codec can output multiple frames per AVPacket
1233  * Normally demuxers return one frame at a time, demuxers which do not do
1234  * are connected to a parser to split what they return into proper frames.
1235  * This flag is reserved to the very rare category of codecs which have a
1236  * bitstream that cannot be split into frames without timeconsuming
1237  * operations like full decoding. Demuxers carrying such bitstreams thus
1238  * may return multiple frames in a packet. This has many disadvantages like
1239  * prohibiting stream copy in many cases thus it should only be considered
1240  * as a last resort.
1241  */
1242 #define CODEC_CAP_SUBFRAMES AV_CODEC_CAP_SUBFRAMES
1243 /**
1244  * Codec is experimental and is thus avoided in favor of non experimental
1245  * encoders
1246  */
1247 #define CODEC_CAP_EXPERIMENTAL AV_CODEC_CAP_EXPERIMENTAL
1248 /**
1249  * Codec should fill in channel configuration and samplerate instead of container
1250  */
1251 #define CODEC_CAP_CHANNEL_CONF AV_CODEC_CAP_CHANNEL_CONF
1252 #if FF_API_NEG_LINESIZES
1253 /**
1254  * @deprecated no codecs use this capability
1255  */
1256 #define CODEC_CAP_NEG_LINESIZES 0x0800
1257 #endif
1258 /**
1259  * Codec supports frame-level multithreading.
1260  */
1261 #define CODEC_CAP_FRAME_THREADS AV_CODEC_CAP_FRAME_THREADS
1262 /**
1263  * Codec supports slice-based (or partition-based) multithreading.
1264  */
1265 #define CODEC_CAP_SLICE_THREADS AV_CODEC_CAP_SLICE_THREADS
1266 /**
1267  * Codec supports changed parameters at any point.
1268  */
1269 #define CODEC_CAP_PARAM_CHANGE AV_CODEC_CAP_PARAM_CHANGE
1270 /**
1271  * Codec supports avctx->thread_count == 0 (auto).
1272  */
1273 #define CODEC_CAP_AUTO_THREADS AV_CODEC_CAP_AUTO_THREADS
1274 /**
1275  * Audio encoder supports receiving a different number of samples in each call.
1276  */
1277 #define CODEC_CAP_VARIABLE_FRAME_SIZE AV_CODEC_CAP_VARIABLE_FRAME_SIZE
1278 /**
1279  * Codec is intra only.
1280  */
1281 #define CODEC_CAP_INTRA_ONLY AV_CODEC_CAP_INTRA_ONLY
1282 /**
1283  * Codec is lossless.
1284  */
1285 #define CODEC_CAP_LOSSLESS AV_CODEC_CAP_LOSSLESS
1286 
1287 /**
1288  * HWAccel is experimental and is thus avoided in favor of non experimental
1289  * codecs
1290  */
1291 #define HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
1292 #endif /* FF_API_WITHOUT_PREFIX */
1293 
1294 #if FF_API_MB_TYPE
1295 //The following defines may change, don't expect compatibility if you use them.
1296 #define MB_TYPE_INTRA4x4 0x0001
1297 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
1298 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
1299 #define MB_TYPE_16x16 0x0008
1300 #define MB_TYPE_16x8 0x0010
1301 #define MB_TYPE_8x16 0x0020
1302 #define MB_TYPE_8x8 0x0040
1303 #define MB_TYPE_INTERLACED 0x0080
1304 #define MB_TYPE_DIRECT2 0x0100 //FIXME
1305 #define MB_TYPE_ACPRED 0x0200
1306 #define MB_TYPE_GMC 0x0400
1307 #define MB_TYPE_SKIP 0x0800
1308 #define MB_TYPE_P0L0 0x1000
1309 #define MB_TYPE_P1L0 0x2000
1310 #define MB_TYPE_P0L1 0x4000
1311 #define MB_TYPE_P1L1 0x8000
1312 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
1313 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
1314 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
1315 #define MB_TYPE_QUANT 0x00010000
1316 #define MB_TYPE_CBP 0x00020000
1317 // Note bits 24-31 are reserved for codec specific use (H.264 ref0, MPEG-1 0mv, ...)
1318 #endif
1319 
1320 /**
1321  * Pan Scan area.
1322  * This specifies the area which should be displayed.
1323  * Note there may be multiple such areas for one frame.
1324  */
1325 typedef struct AVPanScan{
1326  /**
1327  * id
1328  * - encoding: Set by user.
1329  * - decoding: Set by libavcodec.
1330  */
1331  int id;
1332 
1333  /**
1334  * width and height in 1/16 pel
1335  * - encoding: Set by user.
1336  * - decoding: Set by libavcodec.
1337  */
1338  int width;
1339  int height;
1340 
1341  /**
1342  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1343  * - encoding: Set by user.
1344  * - decoding: Set by libavcodec.
1345  */
1346  int16_t position[3][2];
1347 }AVPanScan;
1348 
1349 /**
1350  * This structure describes the bitrate properties of an encoded bitstream. It
1351  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1352  * parameters for H.264/HEVC.
1353  */
1354 typedef struct AVCPBProperties {
1355  /**
1356  * Maximum bitrate of the stream, in bits per second.
1357  * Zero if unknown or unspecified.
1358  */
1360  /**
1361  * Minimum bitrate of the stream, in bits per second.
1362  * Zero if unknown or unspecified.
1363  */
1365  /**
1366  * Average bitrate of the stream, in bits per second.
1367  * Zero if unknown or unspecified.
1368  */
1370 
1371  /**
1372  * The size of the buffer to which the ratecontrol is applied, in bits.
1373  * Zero if unknown or unspecified.
1374  */
1376 
1377  /**
1378  * The delay between the time the packet this structure is associated with
1379  * is received and the time when it should be decoded, in periods of a 27MHz
1380  * clock.
1381  *
1382  * UINT64_MAX when unknown or unspecified.
1383  */
1384  uint64_t vbv_delay;
1385 } AVCPBProperties;
1386 
1387 #if FF_API_QSCALE_TYPE
1388 #define FF_QSCALE_TYPE_MPEG1 0
1389 #define FF_QSCALE_TYPE_MPEG2 1
1390 #define FF_QSCALE_TYPE_H264 2
1391 #define FF_QSCALE_TYPE_VP56 3
1392 #endif
1393 
1394 /**
1395  * The decoder will keep a reference to the frame and may reuse it later.
1396  */
1397 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1398 
1399 /**
1400  * @defgroup lavc_packet AVPacket
1401  *
1402  * Types and functions for working with AVPacket.
1403  * @{
1404  */
1406  /**
1407  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1408  * bytes worth of palette. This side data signals that a new palette is
1409  * present.
1410  */
1412 
1413  /**
1414  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1415  * that the extradata buffer was changed and the receiving side should
1416  * act upon it appropriately. The new extradata is embedded in the side
1417  * data buffer and should be immediately used for processing the current
1418  * frame or packet.
1419  */
1421 
1422  /**
1423  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1424  * @code
1425  * u32le param_flags
1426  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1427  * s32le channel_count
1428  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1429  * u64le channel_layout
1430  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1431  * s32le sample_rate
1432  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1433  * s32le width
1434  * s32le height
1435  * @endcode
1436  */
1438 
1439  /**
1440  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1441  * structures with info about macroblocks relevant to splitting the
1442  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1443  * That is, it does not necessarily contain info about all macroblocks,
1444  * as long as the distance between macroblocks in the info is smaller
1445  * than the target payload size.
1446  * Each MB info structure is 12 bytes, and is laid out as follows:
1447  * @code
1448  * u32le bit offset from the start of the packet
1449  * u8 current quantizer at the start of the macroblock
1450  * u8 GOB number
1451  * u16le macroblock address within the GOB
1452  * u8 horizontal MV predictor
1453  * u8 vertical MV predictor
1454  * u8 horizontal MV predictor for block number 3
1455  * u8 vertical MV predictor for block number 3
1456  * @endcode
1457  */
1459 
1460  /**
1461  * This side data should be associated with an audio stream and contains
1462  * ReplayGain information in form of the AVReplayGain struct.
1463  */
1465 
1466  /**
1467  * This side data contains a 3x3 transformation matrix describing an affine
1468  * transformation that needs to be applied to the decoded video frames for
1469  * correct presentation.
1470  *
1471  * See libavutil/display.h for a detailed description of the data.
1472  */
1474 
1475  /**
1476  * This side data should be associated with a video stream and contains
1477  * Stereoscopic 3D information in form of the AVStereo3D struct.
1478  */
1480 
1481  /**
1482  * This side data should be associated with an audio stream and corresponds
1483  * to enum AVAudioServiceType.
1484  */
1486 
1487  /**
1488  * This side data contains quality related information from the encoder.
1489  * @code
1490  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1491  * u8 picture type
1492  * u8 error count
1493  * u16 reserved
1494  * u64le[error count] sum of squared differences between encoder in and output
1495  * @endcode
1496  */
1498 
1499  /**
1500  * This side data contains an integer value representing the stream index
1501  * of a "fallback" track. A fallback track indicates an alternate
1502  * track to use when the current track can not be decoded for some reason.
1503  * e.g. no decoder available for codec.
1504  */
1506 
1507  /**
1508  * This side data corresponds to the AVCPBProperties struct.
1509  */
1511 
1512  /**
1513  * Recommmends skipping the specified number of samples
1514  * @code
1515  * u32le number of samples to skip from start of this packet
1516  * u32le number of samples to skip from end of this packet
1517  * u8 reason for start skip
1518  * u8 reason for end skip (0=padding silence, 1=convergence)
1519  * @endcode
1520  */
1522 
1523  /**
1524  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1525  * the packet may contain "dual mono" audio specific to Japanese DTV
1526  * and if it is true, recommends only the selected channel to be used.
1527  * @code
1528  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1529  * @endcode
1530  */
1532 
1533  /**
1534  * A list of zero terminated key/value strings. There is no end marker for
1535  * the list, so it is required to rely on the side data size to stop.
1536  */
1538 
1539  /**
1540  * Subtitle event position
1541  * @code
1542  * u32le x1
1543  * u32le y1
1544  * u32le x2
1545  * u32le y2
1546  * @endcode
1547  */
1549 
1550  /**
1551  * Data found in BlockAdditional element of matroska container. There is
1552  * no end marker for the data, so it is required to rely on the side data
1553  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1554  * by data.
1555  */
1557 
1558  /**
1559  * The optional first identifier line of a WebVTT cue.
1560  */
1562 
1563  /**
1564  * The optional settings (rendering instructions) that immediately
1565  * follow the timestamp specifier of a WebVTT cue.
1566  */
1568 
1569  /**
1570  * A list of zero terminated key/value strings. There is no end marker for
1571  * the list, so it is required to rely on the side data size to stop. This
1572  * side data includes updated metadata which appeared in the stream.
1573  */
1575 
1576  /**
1577  * MPEGTS stream ID, this is required to pass the stream ID
1578  * information from the demuxer to the corresponding muxer.
1579  */
1581 
1582  /**
1583  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1584  * should be associated with a video stream and contains data in the form
1585  * of the AVMasteringDisplayMetadata struct.
1586  */
1588 
1589  /**
1590  * This side data should be associated with a video stream and corresponds
1591  * to the AVSphericalMapping structure.
1592  */
1594 
1595  /**
1596  * Content light level (based on CTA-861.3). This metadata should be
1597  * associated with a video stream and contains data in the form of the
1598  * AVContentLightMetadata struct.
1599  */
1601 
1602  /**
1603  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1604  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1605  * The number of bytes of CC data is AVPacketSideData.size.
1606  */
1608 
1609  /**
1610  * The number of side data elements (in fact a bit more than it).
1611  * This is not part of the public API/ABI in the sense that it may
1612  * change when new side data types are added.
1613  * This must stay the last enum value.
1614  * If its value becomes huge, some code using it
1615  * needs to be updated as it assumes it to be smaller than other limits.
1616  */
1618 };
1619 
1620 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1621 
1622 typedef struct AVPacketSideData {
1624  int size;
1627 
1628 /**
1629  * This structure stores compressed data. It is typically exported by demuxers
1630  * and then passed as input to decoders, or received as output from encoders and
1631  * then passed to muxers.
1632  *
1633  * For video, it should typically contain one compressed frame. For audio it may
1634  * contain several compressed frames. Encoders are allowed to output empty
1635  * packets, with no compressed data, containing only side data
1636  * (e.g. to update some stream parameters at the end of encoding).
1637  *
1638  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1639  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1640  * without libavcodec and libavformat major bump.
1641  *
1642  * The semantics of data ownership depends on the buf field.
1643  * If it is set, the packet data is dynamically allocated and is
1644  * valid indefinitely until a call to av_packet_unref() reduces the
1645  * reference count to 0.
1646  *
1647  * If the buf field is not set av_packet_ref() would make a copy instead
1648  * of increasing the reference count.
1649  *
1650  * The side data is always allocated with av_malloc(), copied by
1651  * av_packet_ref() and freed by av_packet_unref().
1652  *
1653  * @see av_packet_ref
1654  * @see av_packet_unref
1655  */
1656 typedef struct AVPacket {
1657  /**
1658  * A reference to the reference-counted buffer where the packet data is
1659  * stored.
1660  * May be NULL, then the packet data is not reference-counted.
1661  */
1663  /**
1664  * Presentation timestamp in AVStream->time_base units; the time at which
1665  * the decompressed packet will be presented to the user.
1666  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1667  * pts MUST be larger or equal to dts as presentation cannot happen before
1668  * decompression, unless one wants to view hex dumps. Some formats misuse
1669  * the terms dts and pts/cts to mean something different. Such timestamps
1670  * must be converted to true pts/dts before they are stored in AVPacket.
1671  */
1672  int64_t pts;
1673  /**
1674  * Decompression timestamp in AVStream->time_base units; the time at which
1675  * the packet is decompressed.
1676  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1677  */
1678  int64_t dts;
1680  int size;
1682  /**
1683  * A combination of AV_PKT_FLAG values
1684  */
1685  int flags;
1686  /**
1687  * Additional packet data that can be provided by the container.
1688  * Packet can contain several types of side information.
1689  */
1692 
1693  /**
1694  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1695  * Equals next_pts - this_pts in presentation order.
1696  */
1697  int64_t duration;
1698 
1699  int64_t pos; ///< byte position in stream, -1 if unknown
1700 
1701 #if FF_API_CONVERGENCE_DURATION
1702  /**
1703  * @deprecated Same as the duration field, but as int64_t. This was required
1704  * for Matroska subtitles, whose duration values could overflow when the
1705  * duration field was still an int.
1706  */
1709 #endif
1710 } AVPacket;
1711 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1712 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1713 /**
1714  * Flag is used to discard packets which are required to maintain valid
1715  * decoder state but are not required for output and should be dropped
1716  * after decoding.
1717  **/
1718 #define AV_PKT_FLAG_DISCARD 0x0004
1719 /**
1720  * The packet comes from a trusted source.
1721  *
1722  * Otherwise-unsafe constructs such as arbitrary pointers to data
1723  * outside the packet may be followed.
1724  */
1725 #define AV_PKT_FLAG_TRUSTED 0x0008
1726 
1732 };
1733 /**
1734  * @}
1735  */
1736 
1737 struct AVCodecInternal;
1738 
1742  AV_FIELD_TT, //< Top coded_first, top displayed first
1743  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1744  AV_FIELD_TB, //< Top coded first, bottom displayed first
1745  AV_FIELD_BT, //< Bottom coded first, top displayed first
1746 };
1747 
1748 /**
1749  * main external API structure.
1750  * New fields can be added to the end with minor version bumps.
1751  * Removal, reordering and changes to existing fields require a major
1752  * version bump.
1753  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1754  * applications.
1755  * The name string for AVOptions options matches the associated command line
1756  * parameter name and can be found in libavcodec/options_table.h
1757  * The AVOption/command line parameter names differ in some cases from the C
1758  * structure field names for historic reasons or brevity.
1759  * sizeof(AVCodecContext) must not be used outside libav*.
1760  */
1761 typedef struct AVCodecContext {
1762  /**
1763  * information on struct for av_log
1764  * - set by avcodec_alloc_context3
1765  */
1768 
1769  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1770  const struct AVCodec *codec;
1771 #if FF_API_CODEC_NAME
1772  /**
1773  * @deprecated this field is not used for anything in libavcodec
1774  */
1776  char codec_name[32];
1777 #endif
1778  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1779 
1780  /**
1781  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1782  * This is used to work around some encoder bugs.
1783  * A demuxer should set this to what is stored in the field used to identify the codec.
1784  * If there are multiple such fields in a container then the demuxer should choose the one
1785  * which maximizes the information about the used codec.
1786  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1787  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1788  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1789  * first.
1790  * - encoding: Set by user, if not then the default based on codec_id will be used.
1791  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1792  */
1793  unsigned int codec_tag;
1794 
1795 #if FF_API_STREAM_CODEC_TAG
1796  /**
1797  * @deprecated this field is unused
1798  */
1800  unsigned int stream_codec_tag;
1801 #endif
1802 
1803  void *priv_data;
1804 
1805  /**
1806  * Private context used for internal data.
1807  *
1808  * Unlike priv_data, this is not codec-specific. It is used in general
1809  * libavcodec functions.
1810  */
1811  struct AVCodecInternal *internal;
1812 
1813  /**
1814  * Private data of the user, can be used to carry app specific stuff.
1815  * - encoding: Set by user.
1816  * - decoding: Set by user.
1817  */
1818  void *opaque;
1819 
1820  /**
1821  * the average bitrate
1822  * - encoding: Set by user; unused for constant quantizer encoding.
1823  * - decoding: Set by user, may be overwritten by libavcodec
1824  * if this info is available in the stream
1825  */
1826  int64_t bit_rate;
1827 
1828  /**
1829  * number of bits the bitstream is allowed to diverge from the reference.
1830  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1831  * - encoding: Set by user; unused for constant quantizer encoding.
1832  * - decoding: unused
1833  */
1835 
1836  /**
1837  * Global quality for codecs which cannot change it per frame.
1838  * This should be proportional to MPEG-1/2/4 qscale.
1839  * - encoding: Set by user.
1840  * - decoding: unused
1841  */
1843 
1844  /**
1845  * - encoding: Set by user.
1846  * - decoding: unused
1847  */
1849 #define FF_COMPRESSION_DEFAULT -1
1850 
1851  /**
1852  * AV_CODEC_FLAG_*.
1853  * - encoding: Set by user.
1854  * - decoding: Set by user.
1855  */
1856  int flags;
1857 
1858  /**
1859  * AV_CODEC_FLAG2_*
1860  * - encoding: Set by user.
1861  * - decoding: Set by user.
1862  */
1863  int flags2;
1864 
1865  /**
1866  * some codecs need / can use extradata like Huffman tables.
1867  * MJPEG: Huffman tables
1868  * rv10: additional flags
1869  * MPEG-4: global headers (they can be in the bitstream or here)
1870  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1871  * than extradata_size to avoid problems if it is read with the bitstream reader.
1872  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1873  * - encoding: Set/allocated/freed by libavcodec.
1874  * - decoding: Set/allocated/freed by user.
1875  */
1878 
1879  /**
1880  * This is the fundamental unit of time (in seconds) in terms
1881  * of which frame timestamps are represented. For fixed-fps content,
1882  * timebase should be 1/framerate and timestamp increments should be
1883  * identically 1.
1884  * This often, but not always is the inverse of the frame rate or field rate
1885  * for video. 1/time_base is not the average frame rate if the frame rate is not
1886  * constant.
1887  *
1888  * Like containers, elementary streams also can store timestamps, 1/time_base
1889  * is the unit in which these timestamps are specified.
1890  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1891  * vop_time_increment_resolution and fixed_vop_rate
1892  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1893  *
1894  * - encoding: MUST be set by user.
1895  * - decoding: the use of this field for decoding is deprecated.
1896  * Use framerate instead.
1897  */
1899 
1900  /**
1901  * For some codecs, the time base is closer to the field rate than the frame rate.
1902  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1903  * if no telecine is used ...
1904  *
1905  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1906  */
1908 
1909  /**
1910  * Codec delay.
1911  *
1912  * Encoding: Number of frames delay there will be from the encoder input to
1913  * the decoder output. (we assume the decoder matches the spec)
1914  * Decoding: Number of frames delay in addition to what a standard decoder
1915  * as specified in the spec would produce.
1916  *
1917  * Video:
1918  * Number of frames the decoded output will be delayed relative to the
1919  * encoded input.
1920  *
1921  * Audio:
1922  * For encoding, this field is unused (see initial_padding).
1923  *
1924  * For decoding, this is the number of samples the decoder needs to
1925  * output before the decoder's output is valid. When seeking, you should
1926  * start decoding this many samples prior to your desired seek point.
1927  *
1928  * - encoding: Set by libavcodec.
1929  * - decoding: Set by libavcodec.
1930  */
1931  int delay;
1932 
1933 
1934  /* video only */
1935  /**
1936  * picture width / height.
1937  *
1938  * @note Those fields may not match the values of the last
1939  * AVFrame output by avcodec_decode_video2 due frame
1940  * reordering.
1941  *
1942  * - encoding: MUST be set by user.
1943  * - decoding: May be set by the user before opening the decoder if known e.g.
1944  * from the container. Some decoders will require the dimensions
1945  * to be set by the caller. During decoding, the decoder may
1946  * overwrite those values as required while parsing the data.
1947  */
1949 
1950  /**
1951  * Bitstream width / height, may be different from width/height e.g. when
1952  * the decoded frame is cropped before being output or lowres is enabled.
1953  *
1954  * @note Those field may not match the value of the last
1955  * AVFrame output by avcodec_receive_frame() due frame
1956  * reordering.
1957  *
1958  * - encoding: unused
1959  * - decoding: May be set by the user before opening the decoder if known
1960  * e.g. from the container. During decoding, the decoder may
1961  * overwrite those values as required while parsing the data.
1962  */
1964 
1965 #if FF_API_ASPECT_EXTENDED
1966 #define FF_ASPECT_EXTENDED 15
1967 #endif
1968 
1969  /**
1970  * the number of pictures in a group of pictures, or 0 for intra_only
1971  * - encoding: Set by user.
1972  * - decoding: unused
1973  */
1975 
1976  /**
1977  * Pixel format, see AV_PIX_FMT_xxx.
1978  * May be set by the demuxer if known from headers.
1979  * May be overridden by the decoder if it knows better.
1980  *
1981  * @note This field may not match the value of the last
1982  * AVFrame output by avcodec_receive_frame() due frame
1983  * reordering.
1984  *
1985  * - encoding: Set by user.
1986  * - decoding: Set by user if known, overridden by libavcodec while
1987  * parsing the data.
1988  */
1990 
1991 #if FF_API_MOTION_EST
1992  /**
1993  * This option does nothing
1994  * @deprecated use codec private options instead
1995  */
1997 #endif
1998 
1999  /**
2000  * If non NULL, 'draw_horiz_band' is called by the libavcodec
2001  * decoder to draw a horizontal band. It improves cache usage. Not
2002  * all codecs can do that. You must check the codec capabilities
2003  * beforehand.
2004  * When multithreading is used, it may be called from multiple threads
2005  * at the same time; threads might draw different parts of the same AVFrame,
2006  * or multiple AVFrames, and there is no guarantee that slices will be drawn
2007  * in order.
2008  * The function is also used by hardware acceleration APIs.
2009  * It is called at least once during frame decoding to pass
2010  * the data needed for hardware render.
2011  * In that mode instead of pixel data, AVFrame points to
2012  * a structure specific to the acceleration API. The application
2013  * reads the structure and can change some fields to indicate progress
2014  * or mark state.
2015  * - encoding: unused
2016  * - decoding: Set by user.
2017  * @param height the height of the slice
2018  * @param y the y position of the slice
2019  * @param type 1->top field, 2->bottom field, 3->frame
2020  * @param offset offset into the AVFrame.data from which the slice should be read
2021  */
2023  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
2024  int y, int type, int height);
2025 
2026  /**
2027  * callback to negotiate the pixelFormat
2028  * @param fmt is the list of formats which are supported by the codec,
2029  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
2030  * The first is always the native one.
2031  * @note The callback may be called again immediately if initialization for
2032  * the selected (hardware-accelerated) pixel format failed.
2033  * @warning Behavior is undefined if the callback returns a value not
2034  * in the fmt list of formats.
2035  * @return the chosen format
2036  * - encoding: unused
2037  * - decoding: Set by user, if not set the native format will be chosen.
2038  */
2039  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
2040 
2041  /**
2042  * maximum number of B-frames between non-B-frames
2043  * Note: The output will be delayed by max_b_frames+1 relative to the input.
2044  * - encoding: Set by user.
2045  * - decoding: unused
2046  */
2048 
2049  /**
2050  * qscale factor between IP and B-frames
2051  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
2052  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
2053  * - encoding: Set by user.
2054  * - decoding: unused
2055  */
2057 
2058 #if FF_API_RC_STRATEGY
2059  /** @deprecated use codec private option instead */
2061 #define FF_RC_STRATEGY_XVID 1
2062 #endif
2063 
2064 #if FF_API_PRIVATE_OPT
2065  /** @deprecated use encoder private options instead */
2068 #endif
2069 
2070  /**
2071  * qscale offset between IP and B-frames
2072  * - encoding: Set by user.
2073  * - decoding: unused
2074  */
2076 
2077  /**
2078  * Size of the frame reordering buffer in the decoder.
2079  * For MPEG-2 it is 1 IPB or 0 low delay IP.
2080  * - encoding: Set by libavcodec.
2081  * - decoding: Set by libavcodec.
2082  */
2084 
2085 #if FF_API_PRIVATE_OPT
2086  /** @deprecated use encoder private options instead */
2089 #endif
2090 
2091  /**
2092  * qscale factor between P- and I-frames
2093  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
2094  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
2095  * - encoding: Set by user.
2096  * - decoding: unused
2097  */
2099 
2100  /**
2101  * qscale offset between P and I-frames
2102  * - encoding: Set by user.
2103  * - decoding: unused
2104  */
2106 
2107  /**
2108  * luminance masking (0-> disabled)
2109  * - encoding: Set by user.
2110  * - decoding: unused
2111  */
2113 
2114  /**
2115  * temporary complexity masking (0-> disabled)
2116  * - encoding: Set by user.
2117  * - decoding: unused
2118  */
2120 
2121  /**
2122  * spatial complexity masking (0-> disabled)
2123  * - encoding: Set by user.
2124  * - decoding: unused
2125  */
2127 
2128  /**
2129  * p block masking (0-> disabled)
2130  * - encoding: Set by user.
2131  * - decoding: unused
2132  */
2133  float p_masking;
2134 
2135  /**
2136  * darkness masking (0-> disabled)
2137  * - encoding: Set by user.
2138  * - decoding: unused
2139  */
2141 
2142  /**
2143  * slice count
2144  * - encoding: Set by libavcodec.
2145  * - decoding: Set by user (or 0).
2146  */
2148 
2149 #if FF_API_PRIVATE_OPT
2150  /** @deprecated use encoder private options instead */
2153 #define FF_PRED_LEFT 0
2154 #define FF_PRED_PLANE 1
2155 #define FF_PRED_MEDIAN 2
2156 #endif
2157 
2158  /**
2159  * slice offsets in the frame in bytes
2160  * - encoding: Set/allocated by libavcodec.
2161  * - decoding: Set/allocated by user (or NULL).
2162  */
2164 
2165  /**
2166  * sample aspect ratio (0 if unknown)
2167  * That is the width of a pixel divided by the height of the pixel.
2168  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
2169  * - encoding: Set by user.
2170  * - decoding: Set by libavcodec.
2171  */
2173 
2174  /**
2175  * motion estimation comparison function
2176  * - encoding: Set by user.
2177  * - decoding: unused
2178  */
2179  int me_cmp;
2180  /**
2181  * subpixel motion estimation comparison function
2182  * - encoding: Set by user.
2183  * - decoding: unused
2184  */
2186  /**
2187  * macroblock comparison function (not supported yet)
2188  * - encoding: Set by user.
2189  * - decoding: unused
2190  */
2191  int mb_cmp;
2192  /**
2193  * interlaced DCT comparison function
2194  * - encoding: Set by user.
2195  * - decoding: unused
2196  */
2198 #define FF_CMP_SAD 0
2199 #define FF_CMP_SSE 1
2200 #define FF_CMP_SATD 2
2201 #define FF_CMP_DCT 3
2202 #define FF_CMP_PSNR 4
2203 #define FF_CMP_BIT 5
2204 #define FF_CMP_RD 6
2205 #define FF_CMP_ZERO 7
2206 #define FF_CMP_VSAD 8
2207 #define FF_CMP_VSSE 9
2208 #define FF_CMP_NSSE 10
2209 #define FF_CMP_W53 11
2210 #define FF_CMP_W97 12
2211 #define FF_CMP_DCTMAX 13
2212 #define FF_CMP_DCT264 14
2213 #define FF_CMP_MEDIAN_SAD 15
2214 #define FF_CMP_CHROMA 256
2215 
2216  /**
2217  * ME diamond size & shape
2218  * - encoding: Set by user.
2219  * - decoding: unused
2220  */
2222 
2223  /**
2224  * amount of previous MV predictors (2a+1 x 2a+1 square)
2225  * - encoding: Set by user.
2226  * - decoding: unused
2227  */
2229 
2230 #if FF_API_PRIVATE_OPT
2231  /** @deprecated use encoder private options instead */
2233  int pre_me;
2234 #endif
2235 
2236  /**
2237  * motion estimation prepass comparison function
2238  * - encoding: Set by user.
2239  * - decoding: unused
2240  */
2242 
2243  /**
2244  * ME prepass diamond size & shape
2245  * - encoding: Set by user.
2246  * - decoding: unused
2247  */
2249 
2250  /**
2251  * subpel ME quality
2252  * - encoding: Set by user.
2253  * - decoding: unused
2254  */
2256 
2257 #if FF_API_AFD
2258  /**
2259  * DTG active format information (additional aspect ratio
2260  * information only used in DVB MPEG-2 transport streams)
2261  * 0 if not set.
2262  *
2263  * - encoding: unused
2264  * - decoding: Set by decoder.
2265  * @deprecated Deprecated in favor of AVSideData
2266  */
2268 #define FF_DTG_AFD_SAME 8
2269 #define FF_DTG_AFD_4_3 9
2270 #define FF_DTG_AFD_16_9 10
2271 #define FF_DTG_AFD_14_9 11
2272 #define FF_DTG_AFD_4_3_SP_14_9 13
2273 #define FF_DTG_AFD_16_9_SP_14_9 14
2274 #define FF_DTG_AFD_SP_4_3 15
2275 #endif /* FF_API_AFD */
2276 
2277  /**
2278  * maximum motion estimation search range in subpel units
2279  * If 0 then no limit.
2280  *
2281  * - encoding: Set by user.
2282  * - decoding: unused
2283  */
2285 
2286 #if FF_API_QUANT_BIAS
2287  /**
2288  * @deprecated use encoder private option instead
2289  */
2291 #define FF_DEFAULT_QUANT_BIAS 999999
2292 
2293  /**
2294  * @deprecated use encoder private option instead
2295  */
2297 #endif
2298 
2299  /**
2300  * slice flags
2301  * - encoding: unused
2302  * - decoding: Set by user.
2303  */
2305 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2306 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2307 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2308 
2309 #if FF_API_XVMC
2310  /**
2311  * XVideo Motion Acceleration
2312  * - encoding: forbidden
2313  * - decoding: set by decoder
2314  * @deprecated XvMC doesn't need it anymore.
2315  */
2316  attribute_deprecated int xvmc_acceleration;
2317 #endif /* FF_API_XVMC */
2318 
2319  /**
2320  * macroblock decision mode
2321  * - encoding: Set by user.
2322  * - decoding: unused
2323  */
2325 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2326 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2327 #define FF_MB_DECISION_RD 2 ///< rate distortion
2328 
2329  /**
2330  * custom intra quantization matrix
2331  * - encoding: Set by user, can be NULL.
2332  * - decoding: Set by libavcodec.
2333  */
2334  uint16_t *intra_matrix;
2335 
2336  /**
2337  * custom inter quantization matrix
2338  * - encoding: Set by user, can be NULL.
2339  * - decoding: Set by libavcodec.
2340  */
2341  uint16_t *inter_matrix;
2342 
2343 #if FF_API_PRIVATE_OPT
2344  /** @deprecated use encoder private options instead */
2347 
2348  /** @deprecated use encoder private options instead */
2351 #endif
2352 
2353 #if FF_API_MPV_OPT
2354  /**
2355  * @deprecated this field is unused
2356  */
2359 
2360  /**
2361  * @deprecated this field is unused
2362  */
2365 #endif
2366 
2367  /**
2368  * precision of the intra DC coefficient - 8
2369  * - encoding: Set by user.
2370  * - decoding: Set by libavcodec
2371  */
2373 
2374  /**
2375  * Number of macroblock rows at the top which are skipped.
2376  * - encoding: unused
2377  * - decoding: Set by user.
2378  */
2380 
2381  /**
2382  * Number of macroblock rows at the bottom which are skipped.
2383  * - encoding: unused
2384  * - decoding: Set by user.
2385  */
2387 
2388 #if FF_API_MPV_OPT
2389  /**
2390  * @deprecated use encoder private options instead
2391  */
2394 #endif
2395 
2396  /**
2397  * minimum MB Lagrange multiplier
2398  * - encoding: Set by user.
2399  * - decoding: unused
2400  */
2401  int mb_lmin;
2402 
2403  /**
2404  * maximum MB Lagrange multiplier
2405  * - encoding: Set by user.
2406  * - decoding: unused
2407  */
2408  int mb_lmax;
2409 
2410 #if FF_API_PRIVATE_OPT
2411  /**
2412  * @deprecated use encoder private options instead
2413  */
2416 #endif
2417 
2418  /**
2419  * - encoding: Set by user.
2420  * - decoding: unused
2421  */
2423 
2424 #if FF_API_PRIVATE_OPT
2425  /** @deprecated use encoder private options instead */
2428 #endif
2429 
2430  /**
2431  * minimum GOP size
2432  * - encoding: Set by user.
2433  * - decoding: unused
2434  */
2436 
2437  /**
2438  * number of reference frames
2439  * - encoding: Set by user.
2440  * - decoding: Set by lavc.
2441  */
2442  int refs;
2443 
2444 #if FF_API_PRIVATE_OPT
2445  /** @deprecated use encoder private options instead */
2448 #endif
2449 
2450 #if FF_API_UNUSED_MEMBERS
2451  /**
2452  * Multiplied by qscale for each frame and added to scene_change_score.
2453  * - encoding: Set by user.
2454  * - decoding: unused
2455  */
2457 #endif
2458 
2459  /**
2460  * Note: Value depends upon the compare function used for fullpel ME.
2461  * - encoding: Set by user.
2462  * - decoding: unused
2463  */
2465 
2466 #if FF_API_PRIVATE_OPT
2467  /** @deprecated use encoder private options instead */
2470 #endif
2471 
2472  /**
2473  * Chromaticity coordinates of the source primaries.
2474  * - encoding: Set by user
2475  * - decoding: Set by libavcodec
2476  */
2478 
2479  /**
2480  * Color Transfer Characteristic.
2481  * - encoding: Set by user
2482  * - decoding: Set by libavcodec
2483  */
2485 
2486  /**
2487  * YUV colorspace type.
2488  * - encoding: Set by user
2489  * - decoding: Set by libavcodec
2490  */
2492 
2493  /**
2494  * MPEG vs JPEG YUV range.
2495  * - encoding: Set by user
2496  * - decoding: Set by libavcodec
2497  */
2499 
2500  /**
2501  * This defines the location of chroma samples.
2502  * - encoding: Set by user
2503  * - decoding: Set by libavcodec
2504  */
2506 
2507  /**
2508  * Number of slices.
2509  * Indicates number of picture subdivisions. Used for parallelized
2510  * decoding.
2511  * - encoding: Set by user
2512  * - decoding: unused
2513  */
2514  int slices;
2515 
2516  /** Field order
2517  * - encoding: set by libavcodec
2518  * - decoding: Set by user.
2519  */
2521 
2522  /* audio only */
2523  int sample_rate; ///< samples per second
2524  int channels; ///< number of audio channels
2525 
2526  /**
2527  * audio sample format
2528  * - encoding: Set by user.
2529  * - decoding: Set by libavcodec.
2530  */
2531  enum AVSampleFormat sample_fmt; ///< sample format
2532 
2533  /* The following data should not be initialized. */
2534  /**
2535  * Number of samples per channel in an audio frame.
2536  *
2537  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2538  * except the last must contain exactly frame_size samples per channel.
2539  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2540  * frame size is not restricted.
2541  * - decoding: may be set by some decoders to indicate constant frame size
2542  */
2544 
2545  /**
2546  * Frame counter, set by libavcodec.
2547  *
2548  * - decoding: total number of frames returned from the decoder so far.
2549  * - encoding: total number of frames passed to the encoder so far.
2550  *
2551  * @note the counter is not incremented if encoding/decoding resulted in
2552  * an error.
2553  */
2555 
2556  /**
2557  * number of bytes per packet if constant and known or 0
2558  * Used by some WAV based audio codecs.
2559  */
2561 
2562  /**
2563  * Audio cutoff bandwidth (0 means "automatic")
2564  * - encoding: Set by user.
2565  * - decoding: unused
2566  */
2567  int cutoff;
2568 
2569  /**
2570  * Audio channel layout.
2571  * - encoding: set by user.
2572  * - decoding: set by user, may be overwritten by libavcodec.
2573  */
2574  uint64_t channel_layout;
2575 
2576  /**
2577  * Request decoder to use this channel layout if it can (0 for default)
2578  * - encoding: unused
2579  * - decoding: Set by user.
2580  */
2582 
2583  /**
2584  * Type of service that the audio stream conveys.
2585  * - encoding: Set by user.
2586  * - decoding: Set by libavcodec.
2587  */
2589 
2590  /**
2591  * desired sample format
2592  * - encoding: Not used.
2593  * - decoding: Set by user.
2594  * Decoder will decode to this format if it can.
2595  */
2597 
2598  /**
2599  * This callback is called at the beginning of each frame to get data
2600  * buffer(s) for it. There may be one contiguous buffer for all the data or
2601  * there may be a buffer per each data plane or anything in between. What
2602  * this means is, you may set however many entries in buf[] you feel necessary.
2603  * Each buffer must be reference-counted using the AVBuffer API (see description
2604  * of buf[] below).
2605  *
2606  * The following fields will be set in the frame before this callback is
2607  * called:
2608  * - format
2609  * - width, height (video only)
2610  * - sample_rate, channel_layout, nb_samples (audio only)
2611  * Their values may differ from the corresponding values in
2612  * AVCodecContext. This callback must use the frame values, not the codec
2613  * context values, to calculate the required buffer size.
2614  *
2615  * This callback must fill the following fields in the frame:
2616  * - data[]
2617  * - linesize[]
2618  * - extended_data:
2619  * * if the data is planar audio with more than 8 channels, then this
2620  * callback must allocate and fill extended_data to contain all pointers
2621  * to all data planes. data[] must hold as many pointers as it can.
2622  * extended_data must be allocated with av_malloc() and will be freed in
2623  * av_frame_unref().
2624  * * otherwise extended_data must point to data
2625  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2626  * the frame's data and extended_data pointers must be contained in these. That
2627  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2628  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2629  * and av_buffer_ref().
2630  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2631  * this callback and filled with the extra buffers if there are more
2632  * buffers than buf[] can hold. extended_buf will be freed in
2633  * av_frame_unref().
2634  *
2635  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2636  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2637  * some other means.
2638  *
2639  * Each data plane must be aligned to the maximum required by the target
2640  * CPU.
2641  *
2642  * @see avcodec_default_get_buffer2()
2643  *
2644  * Video:
2645  *
2646  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2647  * (read and/or written to if it is writable) later by libavcodec.
2648  *
2649  * avcodec_align_dimensions2() should be used to find the required width and
2650  * height, as they normally need to be rounded up to the next multiple of 16.
2651  *
2652  * Some decoders do not support linesizes changing between frames.
2653  *
2654  * If frame multithreading is used and thread_safe_callbacks is set,
2655  * this callback may be called from a different thread, but not from more
2656  * than one at once. Does not need to be reentrant.
2657  *
2658  * @see avcodec_align_dimensions2()
2659  *
2660  * Audio:
2661  *
2662  * Decoders request a buffer of a particular size by setting
2663  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2664  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2665  * to a smaller value in the output frame.
2666  *
2667  * As a convenience, av_samples_get_buffer_size() and
2668  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2669  * functions to find the required data size and to fill data pointers and
2670  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2671  * since all planes must be the same size.
2672  *
2673  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2674  *
2675  * - encoding: unused
2676  * - decoding: Set by libavcodec, user can override.
2677  */
2679 
2680  /**
2681  * If non-zero, the decoded audio and video frames returned from
2682  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2683  * and are valid indefinitely. The caller must free them with
2684  * av_frame_unref() when they are not needed anymore.
2685  * Otherwise, the decoded frames must not be freed by the caller and are
2686  * only valid until the next decode call.
2687  *
2688  * This is always automatically enabled if avcodec_receive_frame() is used.
2689  *
2690  * - encoding: unused
2691  * - decoding: set by the caller before avcodec_open2().
2692  */
2695 
2696  /* - encoding parameters */
2697  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2698  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2699 
2700  /**
2701  * minimum quantizer
2702  * - encoding: Set by user.
2703  * - decoding: unused
2704  */
2705  int qmin;
2706 
2707  /**
2708  * maximum quantizer
2709  * - encoding: Set by user.
2710  * - decoding: unused
2711  */
2712  int qmax;
2713 
2714  /**
2715  * maximum quantizer difference between frames
2716  * - encoding: Set by user.
2717  * - decoding: unused
2718  */
2720 
2721 #if FF_API_MPV_OPT
2722  /**
2723  * @deprecated use encoder private options instead
2724  */
2726  float rc_qsquish;
2727 
2732 #endif
2733 
2734  /**
2735  * decoder bitstream buffer size
2736  * - encoding: Set by user.
2737  * - decoding: unused
2738  */
2740 
2741  /**
2742  * ratecontrol override, see RcOverride
2743  * - encoding: Allocated/set/freed by user.
2744  * - decoding: unused
2745  */
2748 
2749 #if FF_API_MPV_OPT
2750  /**
2751  * @deprecated use encoder private options instead
2752  */
2754  const char *rc_eq;
2755 #endif
2756 
2757  /**
2758  * maximum bitrate
2759  * - encoding: Set by user.
2760  * - decoding: Set by user, may be overwritten by libavcodec.
2761  */
2762  int64_t rc_max_rate;
2763 
2764  /**
2765  * minimum bitrate
2766  * - encoding: Set by user.
2767  * - decoding: unused
2768  */
2769  int64_t rc_min_rate;
2770 
2771 #if FF_API_MPV_OPT
2772  /**
2773  * @deprecated use encoder private options instead
2774  */
2777 
2780 #endif
2781 
2782  /**
2783  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2784  * - encoding: Set by user.
2785  * - decoding: unused.
2786  */
2788 
2789  /**
2790  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2791  * - encoding: Set by user.
2792  * - decoding: unused.
2793  */
2795 
2796  /**
2797  * Number of bits which should be loaded into the rc buffer before decoding starts.
2798  * - encoding: Set by user.
2799  * - decoding: unused
2800  */
2802 
2803 #if FF_API_CODER_TYPE
2804 #define FF_CODER_TYPE_VLC 0
2805 #define FF_CODER_TYPE_AC 1
2806 #define FF_CODER_TYPE_RAW 2
2807 #define FF_CODER_TYPE_RLE 3
2808 #if FF_API_UNUSED_MEMBERS
2809 #define FF_CODER_TYPE_DEFLATE 4
2810 #endif /* FF_API_UNUSED_MEMBERS */
2811  /**
2812  * @deprecated use encoder private options instead
2813  */
2816 #endif /* FF_API_CODER_TYPE */
2817 
2818 #if FF_API_PRIVATE_OPT
2819  /** @deprecated use encoder private options instead */
2822 #endif
2823 
2824 #if FF_API_MPV_OPT
2825  /**
2826  * @deprecated use encoder private options instead
2827  */
2829  int lmin;
2830 
2831  /**
2832  * @deprecated use encoder private options instead
2833  */
2835  int lmax;
2836 #endif
2837 
2838 #if FF_API_PRIVATE_OPT
2839  /** @deprecated use encoder private options instead */
2842 
2843  /** @deprecated use encoder private options instead */
2846 
2847  /** @deprecated use encoder private options instead */
2850 
2851  /** @deprecated use encoder private options instead */
2854 #endif /* FF_API_PRIVATE_OPT */
2855 
2856  /**
2857  * trellis RD quantization
2858  * - encoding: Set by user.
2859  * - decoding: unused
2860  */
2861  int trellis;
2862 
2863 #if FF_API_PRIVATE_OPT
2864  /** @deprecated use encoder private options instead */
2867 
2868  /** @deprecated use encoder private options instead */
2871 
2872  /** @deprecated use encoder private options instead */
2875 #endif
2876 
2877 #if FF_API_RTP_CALLBACK
2878  /**
2879  * @deprecated unused
2880  */
2881  /* The RTP callback: This function is called */
2882  /* every time the encoder has a packet to send. */
2883  /* It depends on the encoder if the data starts */
2884  /* with a Start Code (it should). H.263 does. */
2885  /* mb_nb contains the number of macroblocks */
2886  /* encoded in the RTP payload. */
2888  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2889 #endif
2890 
2891 #if FF_API_PRIVATE_OPT
2892  /** @deprecated use encoder private options instead */
2894  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2895  /* do its best to deliver a chunk with size */
2896  /* below rtp_payload_size, the chunk will start */
2897  /* with a start code on some codecs like H.263. */
2898  /* This doesn't take account of any particular */
2899  /* headers inside the transmitted RTP payload. */
2900 #endif
2901 
2902 #if FF_API_STAT_BITS
2903  /* statistics, used for 2-pass encoding */
2905  int mv_bits;
2913  int i_count;
2915  int p_count;
2920 
2921  /** @deprecated this field is unused */
2924 #endif
2925 
2926  /**
2927  * pass1 encoding statistics output buffer
2928  * - encoding: Set by libavcodec.
2929  * - decoding: unused
2930  */
2931  char *stats_out;
2932 
2933  /**
2934  * pass2 encoding statistics input buffer
2935  * Concatenated stuff from stats_out of pass1 should be placed here.
2936  * - encoding: Allocated/set/freed by user.
2937  * - decoding: unused
2938  */
2939  char *stats_in;
2940 
2941  /**
2942  * Work around bugs in encoders which sometimes cannot be detected automatically.
2943  * - encoding: Set by user
2944  * - decoding: Set by user
2945  */
2947 #define FF_BUG_AUTODETECT 1 ///< autodetection
2948 #if FF_API_OLD_MSMPEG4
2949 #define FF_BUG_OLD_MSMPEG4 2
2950 #endif
2951 #define FF_BUG_XVID_ILACE 4
2952 #define FF_BUG_UMP4 8
2953 #define FF_BUG_NO_PADDING 16
2954 #define FF_BUG_AMV 32
2955 #if FF_API_AC_VLC
2956 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2957 #endif
2958 #define FF_BUG_QPEL_CHROMA 64
2959 #define FF_BUG_STD_QPEL 128
2960 #define FF_BUG_QPEL_CHROMA2 256
2961 #define FF_BUG_DIRECT_BLOCKSIZE 512
2962 #define FF_BUG_EDGE 1024
2963 #define FF_BUG_HPEL_CHROMA 2048
2964 #define FF_BUG_DC_CLIP 4096
2965 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2966 #define FF_BUG_TRUNCATED 16384
2967 #define FF_BUG_IEDGE 32768
2968 
2969  /**
2970  * strictly follow the standard (MPEG-4, ...).
2971  * - encoding: Set by user.
2972  * - decoding: Set by user.
2973  * Setting this to STRICT or higher means the encoder and decoder will
2974  * generally do stupid things, whereas setting it to unofficial or lower
2975  * will mean the encoder might produce output that is not supported by all
2976  * spec-compliant decoders. Decoders don't differentiate between normal,
2977  * unofficial and experimental (that is, they always try to decode things
2978  * when they can) unless they are explicitly asked to behave stupidly
2979  * (=strictly conform to the specs)
2980  */
2982 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2983 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2984 #define FF_COMPLIANCE_NORMAL 0
2985 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2986 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2987 
2988  /**
2989  * error concealment flags
2990  * - encoding: unused
2991  * - decoding: Set by user.
2992  */
2994 #define FF_EC_GUESS_MVS 1
2995 #define FF_EC_DEBLOCK 2
2996 #define FF_EC_FAVOR_INTER 256
2997 
2998  /**
2999  * debug
3000  * - encoding: Set by user.
3001  * - decoding: Set by user.
3002  */
3003  int debug;
3004 #define FF_DEBUG_PICT_INFO 1
3005 #define FF_DEBUG_RC 2
3006 #define FF_DEBUG_BITSTREAM 4
3007 #define FF_DEBUG_MB_TYPE 8
3008 #define FF_DEBUG_QP 16
3009 #if FF_API_DEBUG_MV
3010 /**
3011  * @deprecated this option does nothing
3012  */
3013 #define FF_DEBUG_MV 32
3014 #endif
3015 #define FF_DEBUG_DCT_COEFF 0x00000040
3016 #define FF_DEBUG_SKIP 0x00000080
3017 #define FF_DEBUG_STARTCODE 0x00000100
3018 #if FF_API_UNUSED_MEMBERS
3019 #define FF_DEBUG_PTS 0x00000200
3020 #endif /* FF_API_UNUSED_MEMBERS */
3021 #define FF_DEBUG_ER 0x00000400
3022 #define FF_DEBUG_MMCO 0x00000800
3023 #define FF_DEBUG_BUGS 0x00001000
3024 #if FF_API_DEBUG_MV
3025 #define FF_DEBUG_VIS_QP 0x00002000
3026 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
3027 #endif
3028 #define FF_DEBUG_BUFFERS 0x00008000
3029 #define FF_DEBUG_THREADS 0x00010000
3030 #define FF_DEBUG_GREEN_MD 0x00800000
3031 #define FF_DEBUG_NOMC 0x01000000
3032 
3033 #if FF_API_DEBUG_MV
3034  /**
3035  * debug
3036  * - encoding: Set by user.
3037  * - decoding: Set by user.
3038  */
3040 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
3041 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
3042 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
3043 #endif
3044 
3045  /**
3046  * Error recognition; may misdetect some more or less valid parts as errors.
3047  * - encoding: unused
3048  * - decoding: Set by user.
3049  */
3051 
3052 /**
3053  * Verify checksums embedded in the bitstream (could be of either encoded or
3054  * decoded data, depending on the codec) and print an error message on mismatch.
3055  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
3056  * decoder returning an error.
3057  */
3058 #define AV_EF_CRCCHECK (1<<0)
3059 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
3060 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
3061 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
3062 
3063 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
3064 #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
3065 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
3066 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
3067 
3068 
3069  /**
3070  * opaque 64-bit number (generally a PTS) that will be reordered and
3071  * output in AVFrame.reordered_opaque
3072  * - encoding: unused
3073  * - decoding: Set by user.
3074  */
3076 
3077  /**
3078  * Hardware accelerator in use
3079  * - encoding: unused.
3080  * - decoding: Set by libavcodec
3081  */
3083 
3084  /**
3085  * Hardware accelerator context.
3086  * For some hardware accelerators, a global context needs to be
3087  * provided by the user. In that case, this holds display-dependent
3088  * data FFmpeg cannot instantiate itself. Please refer to the
3089  * FFmpeg HW accelerator documentation to know how to fill this
3090  * is. e.g. for VA API, this is a struct vaapi_context.
3091  * - encoding: unused
3092  * - decoding: Set by user
3093  */
3095 
3096  /**
3097  * error
3098  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
3099  * - decoding: unused
3100  */
3102 
3103  /**
3104  * DCT algorithm, see FF_DCT_* below
3105  * - encoding: Set by user.
3106  * - decoding: unused
3107  */
3109 #define FF_DCT_AUTO 0
3110 #define FF_DCT_FASTINT 1
3111 #define FF_DCT_INT 2
3112 #define FF_DCT_MMX 3
3113 #define FF_DCT_ALTIVEC 5
3114 #define FF_DCT_FAAN 6
3115 
3116  /**
3117  * IDCT algorithm, see FF_IDCT_* below.
3118  * - encoding: Set by user.
3119  * - decoding: Set by user.
3120  */
3122 #define FF_IDCT_AUTO 0
3123 #define FF_IDCT_INT 1
3124 #define FF_IDCT_SIMPLE 2
3125 #define FF_IDCT_SIMPLEMMX 3
3126 #define FF_IDCT_ARM 7
3127 #define FF_IDCT_ALTIVEC 8
3128 #if FF_API_ARCH_SH4
3129 #define FF_IDCT_SH4 9
3130 #endif
3131 #define FF_IDCT_SIMPLEARM 10
3132 #if FF_API_UNUSED_MEMBERS
3133 #define FF_IDCT_IPP 13
3134 #endif /* FF_API_UNUSED_MEMBERS */
3135 #define FF_IDCT_XVID 14
3136 #if FF_API_IDCT_XVIDMMX
3137 #define FF_IDCT_XVIDMMX 14
3138 #endif /* FF_API_IDCT_XVIDMMX */
3139 #define FF_IDCT_SIMPLEARMV5TE 16
3140 #define FF_IDCT_SIMPLEARMV6 17
3141 #if FF_API_ARCH_SPARC
3142 #define FF_IDCT_SIMPLEVIS 18
3143 #endif
3144 #define FF_IDCT_FAAN 20
3145 #define FF_IDCT_SIMPLENEON 22
3146 #if FF_API_ARCH_ALPHA
3147 #define FF_IDCT_SIMPLEALPHA 23
3148 #endif
3149 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
3150 #define FF_IDCT_SIMPLEAUTO 128
3151 
3152  /**
3153  * bits per sample/pixel from the demuxer (needed for huffyuv).
3154  * - encoding: Set by libavcodec.
3155  * - decoding: Set by user.
3156  */
3158 
3159  /**
3160  * Bits per sample/pixel of internal libavcodec pixel/sample format.
3161  * - encoding: set by user.
3162  * - decoding: set by libavcodec.
3163  */
3165 
3166 #if FF_API_LOWRES
3167  /**
3168  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3169  * - encoding: unused
3170  * - decoding: Set by user.
3171  */
3172  int lowres;
3173 #endif
3174 
3175 #if FF_API_CODED_FRAME
3176  /**
3177  * the picture in the bitstream
3178  * - encoding: Set by libavcodec.
3179  * - decoding: unused
3180  *
3181  * @deprecated use the quality factor packet side data instead
3182  */
3184 #endif
3185 
3186  /**
3187  * thread count
3188  * is used to decide how many independent tasks should be passed to execute()
3189  * - encoding: Set by user.
3190  * - decoding: Set by user.
3191  */
3193 
3194  /**
3195  * Which multithreading methods to use.
3196  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
3197  * so clients which cannot provide future frames should not use it.
3198  *
3199  * - encoding: Set by user, otherwise the default is used.
3200  * - decoding: Set by user, otherwise the default is used.
3201  */
3203 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
3204 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
3205 
3206  /**
3207  * Which multithreading methods are in use by the codec.
3208  * - encoding: Set by libavcodec.
3209  * - decoding: Set by libavcodec.
3210  */
3212 
3213  /**
3214  * Set by the client if its custom get_buffer() callback can be called
3215  * synchronously from another thread, which allows faster multithreaded decoding.
3216  * draw_horiz_band() will be called from other threads regardless of this setting.
3217  * Ignored if the default get_buffer() is used.
3218  * - encoding: Set by user.
3219  * - decoding: Set by user.
3220  */
3222 
3223  /**
3224  * The codec may call this to execute several independent things.
3225  * It will return only after finishing all tasks.
3226  * The user may replace this with some multithreaded implementation,
3227  * the default implementation will execute the parts serially.
3228  * @param count the number of things to execute
3229  * - encoding: Set by libavcodec, user can override.
3230  * - decoding: Set by libavcodec, user can override.
3231  */
3232  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
3233 
3234  /**
3235  * The codec may call this to execute several independent things.
3236  * It will return only after finishing all tasks.
3237  * The user may replace this with some multithreaded implementation,
3238  * the default implementation will execute the parts serially.
3239  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
3240  * @param c context passed also to func
3241  * @param count the number of things to execute
3242  * @param arg2 argument passed unchanged to func
3243  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
3244  * @param func function that will be called count times, with jobnr from 0 to count-1.
3245  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
3246  * two instances of func executing at the same time will have the same threadnr.
3247  * @return always 0 currently, but code should handle a future improvement where when any call to func
3248  * returns < 0 no further calls to func may be done and < 0 is returned.
3249  * - encoding: Set by libavcodec, user can override.
3250  * - decoding: Set by libavcodec, user can override.
3251  */
3252  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
3253 
3254  /**
3255  * noise vs. sse weight for the nsse comparison function
3256  * - encoding: Set by user.
3257  * - decoding: unused
3258  */
3260 
3261  /**
3262  * profile
3263  * - encoding: Set by user.
3264  * - decoding: Set by libavcodec.
3265  */
3266  int profile;
3267 #define FF_PROFILE_UNKNOWN -99
3268 #define FF_PROFILE_RESERVED -100
3269 
3270 #define FF_PROFILE_AAC_MAIN 0
3271 #define FF_PROFILE_AAC_LOW 1
3272 #define FF_PROFILE_AAC_SSR 2
3273 #define FF_PROFILE_AAC_LTP 3
3274 #define FF_PROFILE_AAC_HE 4
3275 #define FF_PROFILE_AAC_HE_V2 28
3276 #define FF_PROFILE_AAC_LD 22
3277 #define FF_PROFILE_AAC_ELD 38
3278 #define FF_PROFILE_MPEG2_AAC_LOW 128
3279 #define FF_PROFILE_MPEG2_AAC_HE 131
3280 
3281 #define FF_PROFILE_DNXHD 0
3282 #define FF_PROFILE_DNXHR_LB 1
3283 #define FF_PROFILE_DNXHR_SQ 2
3284 #define FF_PROFILE_DNXHR_HQ 3
3285 #define FF_PROFILE_DNXHR_HQX 4
3286 #define FF_PROFILE_DNXHR_444 5
3287 
3288 #define FF_PROFILE_DTS 20
3289 #define FF_PROFILE_DTS_ES 30
3290 #define FF_PROFILE_DTS_96_24 40
3291 #define FF_PROFILE_DTS_HD_HRA 50
3292 #define FF_PROFILE_DTS_HD_MA 60
3293 #define FF_PROFILE_DTS_EXPRESS 70
3294 
3295 #define FF_PROFILE_MPEG2_422 0
3296 #define FF_PROFILE_MPEG2_HIGH 1
3297 #define FF_PROFILE_MPEG2_SS 2
3298 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
3299 #define FF_PROFILE_MPEG2_MAIN 4
3300 #define FF_PROFILE_MPEG2_SIMPLE 5
3301 
3302 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
3303 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
3304 
3305 #define FF_PROFILE_H264_BASELINE 66
3306 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
3307 #define FF_PROFILE_H264_MAIN 77
3308 #define FF_PROFILE_H264_EXTENDED 88
3309 #define FF_PROFILE_H264_HIGH 100
3310 #define FF_PROFILE_H264_HIGH_10 110
3311 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
3312 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
3313 #define FF_PROFILE_H264_HIGH_422 122
3314 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
3315 #define FF_PROFILE_H264_STEREO_HIGH 128
3316 #define FF_PROFILE_H264_HIGH_444 144
3317 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
3318 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
3319 #define FF_PROFILE_H264_CAVLC_444 44
3320 
3321 #define FF_PROFILE_VC1_SIMPLE 0
3322 #define FF_PROFILE_VC1_MAIN 1
3323 #define FF_PROFILE_VC1_COMPLEX 2
3324 #define FF_PROFILE_VC1_ADVANCED 3
3325 
3326 #define FF_PROFILE_MPEG4_SIMPLE 0
3327 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
3328 #define FF_PROFILE_MPEG4_CORE 2
3329 #define FF_PROFILE_MPEG4_MAIN 3
3330 #define FF_PROFILE_MPEG4_N_BIT 4
3331 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
3332 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
3333 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
3334 #define FF_PROFILE_MPEG4_HYBRID 8
3335 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
3336 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
3337 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
3338 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
3339 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
3340 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
3341 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
3342 
3343 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
3344 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
3345 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
3346 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
3347 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
3348 
3349 #define FF_PROFILE_VP9_0 0
3350 #define FF_PROFILE_VP9_1 1
3351 #define FF_PROFILE_VP9_2 2
3352 #define FF_PROFILE_VP9_3 3
3353 
3354 #define FF_PROFILE_HEVC_MAIN 1
3355 #define FF_PROFILE_HEVC_MAIN_10 2
3356 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
3357 #define FF_PROFILE_HEVC_REXT 4
3358 
3359  /**
3360  * level
3361  * - encoding: Set by user.
3362  * - decoding: Set by libavcodec.
3363  */
3364  int level;
3365 #define FF_LEVEL_UNKNOWN -99
3366 
3367  /**
3368  * Skip loop filtering for selected frames.
3369  * - encoding: unused
3370  * - decoding: Set by user.
3371  */
3373 
3374  /**
3375  * Skip IDCT/dequantization for selected frames.
3376  * - encoding: unused
3377  * - decoding: Set by user.
3378  */
3380 
3381  /**
3382  * Skip decoding for selected frames.
3383  * - encoding: unused
3384  * - decoding: Set by user.
3385  */
3387 
3388  /**
3389  * Header containing style information for text subtitles.
3390  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3391  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3392  * the Format line following. It shouldn't include any Dialogue line.
3393  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3394  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3395  */
3398 
3399 #if FF_API_ERROR_RATE
3400  /**
3401  * @deprecated use the 'error_rate' private AVOption of the mpegvideo
3402  * encoders
3403  */
3406 #endif
3407 
3408 #if FF_API_VBV_DELAY
3409  /**
3410  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3411  * Used for compliant TS muxing.
3412  * - encoding: Set by libavcodec.
3413  * - decoding: unused.
3414  * @deprecated this value is now exported as a part of
3415  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3416  */
3418  uint64_t vbv_delay;
3419 #endif
3420 
3421 #if FF_API_SIDEDATA_ONLY_PKT
3422  /**
3423  * Encoding only and set by default. Allow encoders to output packets
3424  * that do not contain any encoded data, only side data.
3425  *
3426  * Some encoders need to output such packets, e.g. to update some stream
3427  * parameters at the end of encoding.
3428  *
3429  * @deprecated this field disables the default behaviour and
3430  * it is kept only for compatibility.
3431  */
3434 #endif
3435 
3436  /**
3437  * Audio only. The number of "priming" samples (padding) inserted by the
3438  * encoder at the beginning of the audio. I.e. this number of leading
3439  * decoded samples must be discarded by the caller to get the original audio
3440  * without leading padding.
3441  *
3442  * - decoding: unused
3443  * - encoding: Set by libavcodec. The timestamps on the output packets are
3444  * adjusted by the encoder so that they always refer to the
3445  * first sample of the data actually contained in the packet,
3446  * including any added padding. E.g. if the timebase is
3447  * 1/samplerate and the timestamp of the first input sample is
3448  * 0, the timestamp of the first output packet will be
3449  * -initial_padding.
3450  */
3452 
3453  /**
3454  * - decoding: For codecs that store a framerate value in the compressed
3455  * bitstream, the decoder may export it here. { 0, 1} when
3456  * unknown.
3457  * - encoding: May be used to signal the framerate of CFR content to an
3458  * encoder.
3459  */
3461 
3462  /**
3463  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3464  * - encoding: unused.
3465  * - decoding: Set by libavcodec before calling get_format()
3466  */
3468 
3469  /**
3470  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3471  * - encoding unused.
3472  * - decoding set by user.
3473  */
3475 
3476  /**
3477  * AVCodecDescriptor
3478  * - encoding: unused.
3479  * - decoding: set by libavcodec.
3480  */
3482 
3483 #if !FF_API_LOWRES
3484  /**
3485  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3486  * - encoding: unused
3487  * - decoding: Set by user.
3488  */
3489  int lowres;
3490 #endif
3491 
3492  /**
3493  * Current statistics for PTS correction.
3494  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3495  * - encoding: unused
3496  */
3497  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3498  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3499  int64_t pts_correction_last_pts; /// PTS of the last frame
3500  int64_t pts_correction_last_dts; /// DTS of the last frame
3501 
3502  /**
3503  * Character encoding of the input subtitles file.
3504  * - decoding: set by user
3505  * - encoding: unused
3506  */
3508 
3509  /**
3510  * Subtitles character encoding mode. Formats or codecs might be adjusting
3511  * this setting (if they are doing the conversion themselves for instance).
3512  * - decoding: set by libavcodec
3513  * - encoding: unused
3514  */
3516 #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)
3517 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3518 #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
3519 
3520  /**
3521  * Skip processing alpha if supported by codec.
3522  * Note that if the format uses pre-multiplied alpha (common with VP6,
3523  * and recommended due to better video quality/compression)
3524  * the image will look as if alpha-blended onto a black background.
3525  * However for formats that do not use pre-multiplied alpha
3526  * there might be serious artefacts (though e.g. libswscale currently
3527  * assumes pre-multiplied alpha anyway).
3528  *
3529  * - decoding: set by user
3530  * - encoding: unused
3531  */
3533 
3534  /**
3535  * Number of samples to skip after a discontinuity
3536  * - decoding: unused
3537  * - encoding: set by libavcodec
3538  */
3540 
3541 #if !FF_API_DEBUG_MV
3542  /**
3543  * debug motion vectors
3544  * - encoding: Set by user.
3545  * - decoding: Set by user.
3546  */
3547  int debug_mv;
3548 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3549 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3550 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3551 #endif
3552 
3553  /**
3554  * custom intra quantization matrix
3555  * - encoding: Set by user, can be NULL.
3556  * - decoding: unused.
3557  */
3559 
3560  /**
3561  * dump format separator.
3562  * can be ", " or "\n " or anything else
3563  * - encoding: Set by user.
3564  * - decoding: Set by user.
3565  */
3567 
3568  /**
3569  * ',' separated list of allowed decoders.
3570  * If NULL then all are allowed
3571  * - encoding: unused
3572  * - decoding: set by user
3573  */
3575 
3576  /**
3577  * Properties of the stream that gets decoded
3578  * - encoding: unused
3579  * - decoding: set by libavcodec
3580  */
3581  unsigned properties;
3582 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3583 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3584 
3585  /**
3586  * Additional data associated with the entire coded stream.
3587  *
3588  * - decoding: unused
3589  * - encoding: may be set by libavcodec after avcodec_open2().
3590  */
3593 
3594  /**
3595  * A reference to the AVHWFramesContext describing the input (for encoding)
3596  * or output (decoding) frames. The reference is set by the caller and
3597  * afterwards owned (and freed) by libavcodec - it should never be read by
3598  * the caller after being set.
3599  *
3600  * - decoding: This field should be set by the caller from the get_format()
3601  * callback. The previous reference (if any) will always be
3602  * unreffed by libavcodec before the get_format() call.
3603  *
3604  * If the default get_buffer2() is used with a hwaccel pixel
3605  * format, then this AVHWFramesContext will be used for
3606  * allocating the frame buffers.
3607  *
3608  * - encoding: For hardware encoders configured to use a hwaccel pixel
3609  * format, this field should be set by the caller to a reference
3610  * to the AVHWFramesContext describing input frames.
3611  * AVHWFramesContext.format must be equal to
3612  * AVCodecContext.pix_fmt.
3613  *
3614  * This field should be set before avcodec_open2() is called.
3615  */
3617 
3618  /**
3619  * Control the form of AVSubtitle.rects[N]->ass
3620  * - decoding: set by user
3621  * - encoding: unused
3622  */
3624 #define FF_SUB_TEXT_FMT_ASS 0
3625 #if FF_API_ASS_TIMING
3626 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3627 #endif
3628 
3629  /**
3630  * Audio only. The amount of padding (in samples) appended by the encoder to
3631  * the end of the audio. I.e. this number of decoded samples must be
3632  * discarded by the caller from the end of the stream to get the original
3633  * audio without any trailing padding.
3634  *
3635  * - decoding: unused
3636  * - encoding: unused
3637  */
3639 
3640  /**
3641  * The number of pixels per image to maximally accept.
3642  *
3643  * - decoding: set by user
3644  * - encoding: set by user
3645  */
3646  int64_t max_pixels;
3647 
3648  /**
3649  * A reference to the AVHWDeviceContext describing the device which will
3650  * be used by a hardware encoder/decoder. The reference is set by the
3651  * caller and afterwards owned (and freed) by libavcodec.
3652  *
3653  * This should be used if either the codec device does not require
3654  * hardware frames or any that are used are to be allocated internally by
3655  * libavcodec. If the user wishes to supply any of the frames used as
3656  * encoder input or decoder output then hw_frames_ctx should be used
3657  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3658  * field will be ignored while decoding the associated stream segment, but
3659  * may again be used on a following one after another get_format() call.
3660  *
3661  * For both encoders and decoders this field should be set before
3662  * avcodec_open2() is called and must not be written to thereafter.
3663  *
3664  * Note that some decoders may require this field to be set initially in
3665  * order to support hw_frames_ctx at all - in that case, all frames
3666  * contexts used must be created on the same device.
3667  */
3669 
3670  /**
3671  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3672  * decoding (if active).
3673  * - encoding: unused
3674  * - decoding: Set by user (either before avcodec_open2(), or in the
3675  * AVCodecContext.get_format callback)
3676  */
3678 
3679  /**
3680  * Video decoding only. Certain video codecs support cropping, meaning that
3681  * only a sub-rectangle of the decoded frame is intended for display. This
3682  * option controls how cropping is handled by libavcodec.
3683  *
3684  * When set to 1 (the default), libavcodec will apply cropping internally.
3685  * I.e. it will modify the output frame width/height fields and offset the
3686  * data pointers (only by as much as possible while preserving alignment, or
3687  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3688  * the frames output by the decoder refer only to the cropped area. The
3689  * crop_* fields of the output frames will be zero.
3690  *
3691  * When set to 0, the width/height fields of the output frames will be set
3692  * to the coded dimensions and the crop_* fields will describe the cropping
3693  * rectangle. Applying the cropping is left to the caller.
3694  *
3695  * @warning When hardware acceleration with opaque output frames is used,
3696  * libavcodec is unable to apply cropping from the top/left border.
3697  *
3698  * @note when this option is set to zero, the width/height fields of the
3699  * AVCodecContext and output AVFrames have different meanings. The codec
3700  * context fields store display dimensions (with the coded dimensions in
3701  * coded_width/height), while the frame fields store the coded dimensions
3702  * (with the display dimensions being determined by the crop_* fields).
3703  */
3705 } AVCodecContext;
3706 
3709 
3712 
3713 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3714 
3715 int av_codec_get_lowres(const AVCodecContext *avctx);
3716 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3717 
3718 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3719 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3720 
3721 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3722 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3723 
3724 /**
3725  * AVProfile.
3726  */
3727 typedef struct AVProfile {
3728  int profile;
3729  const char *name; ///< short name for the profile
3730 } AVProfile;
3731 
3732 typedef struct AVCodecDefault AVCodecDefault;
3733 
3734 struct AVSubtitle;
3735 
3736 /**
3737  * AVCodec.
3738  */
3739 typedef struct AVCodec {
3740  /**
3741  * Name of the codec implementation.
3742  * The name is globally unique among encoders and among decoders (but an
3743  * encoder and a decoder can share the same name).
3744  * This is the primary way to find a codec from the user perspective.
3745  */
3746  const char *name;
3747  /**
3748  * Descriptive name for the codec, meant to be more human readable than name.
3749  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3750  */
3751  const char *long_name;
3754  /**
3755  * Codec capabilities.
3756  * see AV_CODEC_CAP_*
3757  */
3759  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3760  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3761  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3762  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3763  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3764  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3765  const AVClass *priv_class; ///< AVClass for the private context
3766  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3767 
3768  /*****************************************************************
3769  * No fields below this line are part of the public API. They
3770  * may not be used outside of libavcodec and can be changed and
3771  * removed at will.
3772  * New public fields should be added right above.
3773  *****************************************************************
3774  */
3776  struct AVCodec *next;
3777  /**
3778  * @name Frame-level threading support functions
3779  * @{
3780  */
3781  /**
3782  * If defined, called on thread contexts when they are created.
3783  * If the codec allocates writable tables in init(), re-allocate them here.
3784  * priv_data will be set to a copy of the original.
3785  */
3787  /**
3788  * Copy necessary context variables from a previous thread context to the current one.
3789  * If not defined, the next thread will start automatically; otherwise, the codec
3790  * must call ff_thread_finish_setup().
3791  *
3792  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3793  */
3795  /** @} */
3796 
3797  /**
3798  * Private codec-specific defaults.
3799  */
3801 
3802  /**
3803  * Initialize codec static data, called from avcodec_register().
3804  */
3805  void (*init_static_data)(struct AVCodec *codec);
3806 
3808  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3809  const struct AVSubtitle *sub);
3810  /**
3811  * Encode data to an AVPacket.
3812  *
3813  * @param avctx codec context
3814  * @param avpkt output AVPacket (may contain a user-provided buffer)
3815  * @param[in] frame AVFrame containing the raw data to be encoded
3816  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3817  * non-empty packet was returned in avpkt.
3818  * @return 0 on success, negative error code on failure
3819  */
3820  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3821  int *got_packet_ptr);
3822  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3824  /**
3825  * Encode API with decoupled packet/frame dataflow. The API is the
3826  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3827  * that:
3828  * - never called if the codec is closed or the wrong type,
3829  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3830  * - only one drain frame is ever passed down,
3831  */
3834 
3835  /**
3836  * Decode API with decoupled packet/frame dataflow. This function is called
3837  * to get one output frame. It should call ff_decode_get_packet() to obtain
3838  * input data.
3839  */
3841  /**
3842  * Flush buffers.
3843  * Will be called when seeking
3844  */
3846  /**
3847  * Internal codec capabilities.
3848  * See FF_CODEC_CAP_* in internal.h
3849  */
3851 
3852  /**
3853  * Decoding only, a comma-separated list of bitstream filters to apply to
3854  * packets before decoding.
3855  */
3856  const char *bsfs;
3857 } AVCodec;
3858 
3859 int av_codec_get_max_lowres(const AVCodec *codec);
3860 
3861 struct MpegEncContext;
3862 
3863 /**
3864  * @defgroup lavc_hwaccel AVHWAccel
3865  * @{
3866  */
3867 typedef struct AVHWAccel {
3868  /**
3869  * Name of the hardware accelerated codec.
3870  * The name is globally unique among encoders and among decoders (but an
3871  * encoder and a decoder can share the same name).
3872  */
3873  const char *name;
3874 
3875  /**
3876  * Type of codec implemented by the hardware accelerator.
3877  *
3878  * See AVMEDIA_TYPE_xxx
3879  */
3881 
3882  /**
3883  * Codec implemented by the hardware accelerator.
3884  *
3885  * See AV_CODEC_ID_xxx
3886  */
3888 
3889  /**
3890  * Supported pixel format.
3891  *
3892  * Only hardware accelerated formats are supported here.
3893  */
3895 
3896  /**
3897  * Hardware accelerated codec capabilities.
3898  * see AV_HWACCEL_CODEC_CAP_*
3899  */
3901 
3902  /*****************************************************************
3903  * No fields below this line are part of the public API. They
3904  * may not be used outside of libavcodec and can be changed and
3905  * removed at will.
3906  * New public fields should be added right above.
3907  *****************************************************************
3908  */
3909  struct AVHWAccel *next;
3910 
3911  /**
3912  * Allocate a custom buffer
3913  */
3915 
3916  /**
3917  * Called at the beginning of each frame or field picture.
3918  *
3919  * Meaningful frame information (codec specific) is guaranteed to
3920  * be parsed at this point. This function is mandatory.
3921  *
3922  * Note that buf can be NULL along with buf_size set to 0.
3923  * Otherwise, this means the whole frame is available at this point.
3924  *
3925  * @param avctx the codec context
3926  * @param buf the frame data buffer base
3927  * @param buf_size the size of the frame in bytes
3928  * @return zero if successful, a negative value otherwise
3929  */
3930  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3931 
3932  /**
3933  * Callback for each slice.
3934  *
3935  * Meaningful slice information (codec specific) is guaranteed to
3936  * be parsed at this point. This function is mandatory.
3937  * The only exception is XvMC, that works on MB level.
3938  *
3939  * @param avctx the codec context
3940  * @param buf the slice data buffer base
3941  * @param buf_size the size of the slice in bytes
3942  * @return zero if successful, a negative value otherwise
3943  */
3944  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3945 
3946  /**
3947  * Called at the end of each frame or field picture.
3948  *
3949  * The whole picture is parsed at this point and can now be sent
3950  * to the hardware accelerator. This function is mandatory.
3951  *
3952  * @param avctx the codec context
3953  * @return zero if successful, a negative value otherwise
3954  */
3956 
3957  /**
3958  * Size of per-frame hardware accelerator private data.
3959  *
3960  * Private data is allocated with av_mallocz() before
3961  * AVCodecContext.get_buffer() and deallocated after
3962  * AVCodecContext.release_buffer().
3963  */
3965 
3966  /**
3967  * Called for every Macroblock in a slice.
3968  *
3969  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3970  * Instead of decoding to raw picture, MB parameters are
3971  * stored in an array provided by the video driver.
3972  *
3973  * @param s the mpeg context
3974  */
3976 
3977  /**
3978  * Initialize the hwaccel private data.
3979  *
3980  * This will be called from ff_get_format(), after hwaccel and
3981  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3982  * is allocated.
3983  */
3985 
3986  /**
3987  * Uninitialize the hwaccel private data.
3988  *
3989  * This will be called from get_format() or avcodec_close(), after hwaccel
3990  * and hwaccel_context are already uninitialized.
3991  */
3993 
3994  /**
3995  * Size of the private data to allocate in
3996  * AVCodecInternal.hwaccel_priv_data.
3997  */
3999 
4000  /**
4001  * Internal hwaccel capabilities.
4002  */
4004 } AVHWAccel;
4005 
4006 /**
4007  * HWAccel is experimental and is thus avoided in favor of non experimental
4008  * codecs
4009  */
4010 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
4011 
4012 /**
4013  * Hardware acceleration should be used for decoding even if the codec level
4014  * used is unknown or higher than the maximum supported level reported by the
4015  * hardware driver.
4016  *
4017  * It's generally a good idea to pass this flag unless you have a specific
4018  * reason not to, as hardware tends to under-report supported levels.
4019  */
4020 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
4021 
4022 /**
4023  * Hardware acceleration can output YUV pixel formats with a different chroma
4024  * sampling than 4:2:0 and/or other than 8 bits per component.
4025  */
4026 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
4027 
4028 /**
4029  * Hardware acceleration should still be attempted for decoding when the
4030  * codec profile does not match the reported capabilities of the hardware.
4031  *
4032  * For example, this can be used to try to decode baseline profile H.264
4033  * streams in hardware - it will often succeed, because many streams marked
4034  * as baseline profile actually conform to constrained baseline profile.
4035  *
4036  * @warning If the stream is actually not supported then the behaviour is
4037  * undefined, and may include returning entirely incorrect output
4038  * while indicating success.
4039  */
4040 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
4041 
4042 /**
4043  * @}
4044  */
4045 
4046 #if FF_API_AVPICTURE
4047 /**
4048  * @defgroup lavc_picture AVPicture
4049  *
4050  * Functions for working with AVPicture
4051  * @{
4052  */
4053 
4054 /**
4055  * Picture data structure.
4056  *
4057  * Up to four components can be stored into it, the last component is
4058  * alpha.
4059  * @deprecated use AVFrame or imgutils functions instead
4060  */
4061 typedef struct AVPicture {
4063  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
4065  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
4066 } AVPicture;
4067 
4068 /**
4069  * @}
4070  */
4071 #endif
4072 
4075 
4076  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
4077 
4078  /**
4079  * Plain text, the text field must be set by the decoder and is
4080  * authoritative. ass and pict fields may contain approximations.
4081  */
4083 
4084  /**
4085  * Formatted text, the ass field must be set by the decoder and is
4086  * authoritative. pict and text fields may contain approximations.
4087  */
4089 };
4090 
4091 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
4092 
4093 typedef struct AVSubtitleRect {
4094  int x; ///< top left corner of pict, undefined when pict is not set
4095  int y; ///< top left corner of pict, undefined when pict is not set
4096  int w; ///< width of pict, undefined when pict is not set
4097  int h; ///< height of pict, undefined when pict is not set
4098  int nb_colors; ///< number of colors in pict, undefined when pict is not set
4099 
4100 #if FF_API_AVPICTURE
4101  /**
4102  * @deprecated unused
4103  */
4106 #endif
4107  /**
4108  * data+linesize for the bitmap of this subtitle.
4109  * Can be set for text/ass as well once they are rendered.
4110  */
4112  int linesize[4];
4113 
4115 
4116  char *text; ///< 0 terminated plain UTF-8 text
4117 
4118  /**
4119  * 0 terminated ASS/SSA compatible event line.
4120  * The presentation of this is unaffected by the other values in this
4121  * struct.
4122  */
4123  char *ass;
4124 
4125  int flags;
4126 } AVSubtitleRect;
4127 
4128 typedef struct AVSubtitle {
4129  uint16_t format; /* 0 = graphics */
4130  uint32_t start_display_time; /* relative to packet pts, in ms */
4131  uint32_t end_display_time; /* relative to packet pts, in ms */
4132  unsigned num_rects;
4134  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
4135 } AVSubtitle;
4136 
4137 /**
4138  * This struct describes the properties of an encoded stream.
4139  *
4140  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
4141  * be allocated with avcodec_parameters_alloc() and freed with
4142  * avcodec_parameters_free().
4143  */
4144 typedef struct AVCodecParameters {
4145  /**
4146  * General type of the encoded data.
4147  */
4149  /**
4150  * Specific type of the encoded data (the codec used).
4151  */
4153  /**
4154  * Additional information about the codec (corresponds to the AVI FOURCC).
4155  */
4156  uint32_t codec_tag;
4157 
4158  /**
4159  * Extra binary data needed for initializing the decoder, codec-dependent.
4160  *
4161  * Must be allocated with av_malloc() and will be freed by
4162  * avcodec_parameters_free(). The allocated size of extradata must be at
4163  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
4164  * bytes zeroed.
4165  */
4167  /**
4168  * Size of the extradata content in bytes.
4169  */
4171 
4172  /**
4173  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
4174  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
4175  */
4176  int format;
4177 
4178  /**
4179  * The average bitrate of the encoded data (in bits per second).
4180  */
4181  int64_t bit_rate;
4182 
4183  /**
4184  * The number of bits per sample in the codedwords.
4185  *
4186  * This is basically the bitrate per sample. It is mandatory for a bunch of
4187  * formats to actually decode them. It's the number of bits for one sample in
4188  * the actual coded bitstream.
4189  *
4190  * This could be for example 4 for ADPCM
4191  * For PCM formats this matches bits_per_raw_sample
4192  * Can be 0
4193  */
4195 
4196  /**
4197  * This is the number of valid bits in each output sample. If the
4198  * sample format has more bits, the least significant bits are additional
4199  * padding bits, which are always 0. Use right shifts to reduce the sample
4200  * to its actual size. For example, audio formats with 24 bit samples will
4201  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
4202  * To get the original sample use "(int32_t)sample >> 8"."
4203  *
4204  * For ADPCM this might be 12 or 16 or similar
4205  * Can be 0
4206  */
4208 
4209  /**
4210  * Codec-specific bitstream restrictions that the stream conforms to.
4211  */
4212  int profile;
4213  int level;
4214 
4215  /**
4216  * Video only. The dimensions of the video frame in pixels.
4217  */
4218  int width;
4219  int height;
4220 
4221  /**
4222  * Video only. The aspect ratio (width / height) which a single pixel
4223  * should have when displayed.
4224  *
4225  * When the aspect ratio is unknown / undefined, the numerator should be
4226  * set to 0 (the denominator may have any value).
4227  */
4229 
4230  /**
4231  * Video only. The order of the fields in interlaced video.
4232  */
4234 
4235  /**
4236  * Video only. Additional colorspace characteristics.
4237  */
4243 
4244  /**
4245  * Video only. Number of delayed frames.
4246  */
4248 
4249  /**
4250  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4251  * unknown or unspecified, otherwise the number of bits set must be equal to
4252  * the channels field.
4253  */
4254  uint64_t channel_layout;
4255  /**
4256  * Audio only. The number of audio channels.
4257  */
4259  /**
4260  * Audio only. The number of audio samples per second.
4261  */
4263  /**
4264  * Audio only. The number of bytes per coded audio frame, required by some
4265  * formats.
4266  *
4267  * Corresponds to nBlockAlign in WAVEFORMATEX.
4268  */
4270  /**
4271  * Audio only. Audio frame size, if known. Required by some formats to be static.
4272  */
4274 
4275  /**
4276  * Audio only. The amount of padding (in samples) inserted by the encoder at
4277  * the beginning of the audio. I.e. this number of leading decoded samples
4278  * must be discarded by the caller to get the original audio without leading
4279  * padding.
4280  */
4282  /**
4283  * Audio only. The amount of padding (in samples) appended by the encoder to
4284  * the end of the audio. I.e. this number of decoded samples must be
4285  * discarded by the caller from the end of the stream to get the original
4286  * audio without any trailing padding.
4287  */
4289  /**
4290  * Audio only. Number of samples to skip after a discontinuity.
4291  */
4294 
4295 /**
4296  * If c is NULL, returns the first registered codec,
4297  * if c is non-NULL, returns the next registered codec after c,
4298  * or NULL if c is the last one.
4299  */
4300 AVCodec *av_codec_next(const AVCodec *c);
4301 
4302 /**
4303  * Return the LIBAVCODEC_VERSION_INT constant.
4304  */
4305 unsigned avcodec_version(void);
4306 
4307 /**
4308  * Return the libavcodec build-time configuration.
4309  */
4310 const char *avcodec_configuration(void);
4311 
4312 /**
4313  * Return the libavcodec license.
4314  */
4315 const char *avcodec_license(void);
4316 
4317 /**
4318  * Register the codec codec and initialize libavcodec.
4319  *
4320  * @warning either this function or avcodec_register_all() must be called
4321  * before any other libavcodec functions.
4322  *
4323  * @see avcodec_register_all()
4324  */
4325 void avcodec_register(AVCodec *codec);
4326 
4327 /**
4328  * Register all the codecs, parsers and bitstream filters which were enabled at
4329  * configuration time. If you do not call this function you can select exactly
4330  * which formats you want to support, by using the individual registration
4331  * functions.
4332  *
4333  * @see avcodec_register
4334  * @see av_register_codec_parser
4335  * @see av_register_bitstream_filter
4336  */
4337 void avcodec_register_all(void);
4338 
4339 /**
4340  * Allocate an AVCodecContext and set its fields to default values. The
4341  * resulting struct should be freed with avcodec_free_context().
4342  *
4343  * @param codec if non-NULL, allocate private data and initialize defaults
4344  * for the given codec. It is illegal to then call avcodec_open2()
4345  * with a different codec.
4346  * If NULL, then the codec-specific defaults won't be initialized,
4347  * which may result in suboptimal default settings (this is
4348  * important mainly for encoders, e.g. libx264).
4349  *
4350  * @return An AVCodecContext filled with default values or NULL on failure.
4351  */
4353 
4354 /**
4355  * Free the codec context and everything associated with it and write NULL to
4356  * the provided pointer.
4357  */
4358 void avcodec_free_context(AVCodecContext **avctx);
4359 
4360 #if FF_API_GET_CONTEXT_DEFAULTS
4361 /**
4362  * @deprecated This function should not be used, as closing and opening a codec
4363  * context multiple time is not supported. A new codec context should be
4364  * allocated for each new use.
4365  */
4367 #endif
4368 
4369 /**
4370  * Get the AVClass for AVCodecContext. It can be used in combination with
4371  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4372  *
4373  * @see av_opt_find().
4374  */
4375 const AVClass *avcodec_get_class(void);
4376 
4377 #if FF_API_COPY_CONTEXT
4378 /**
4379  * Get the AVClass for AVFrame. It can be used in combination with
4380  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4381  *
4382  * @see av_opt_find().
4383  */
4384 const AVClass *avcodec_get_frame_class(void);
4385 
4386 /**
4387  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4388  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4389  *
4390  * @see av_opt_find().
4391  */
4393 
4394 /**
4395  * Copy the settings of the source AVCodecContext into the destination
4396  * AVCodecContext. The resulting destination codec context will be
4397  * unopened, i.e. you are required to call avcodec_open2() before you
4398  * can use this AVCodecContext to decode/encode video/audio data.
4399  *
4400  * @param dest target codec context, should be initialized with
4401  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4402  * @param src source codec context
4403  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4404  *
4405  * @deprecated The semantics of this function are ill-defined and it should not
4406  * be used. If you need to transfer the stream parameters from one codec context
4407  * to another, use an intermediate AVCodecParameters instance and the
4408  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4409  * functions.
4410  */
4413 #endif
4414 
4415 /**
4416  * Allocate a new AVCodecParameters and set its fields to default values
4417  * (unknown/invalid/0). The returned struct must be freed with
4418  * avcodec_parameters_free().
4419  */
4421 
4422 /**
4423  * Free an AVCodecParameters instance and everything associated with it and
4424  * write NULL to the supplied pointer.
4425  */
4427 
4428 /**
4429  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4430  * replaced with newly allocated duplicates of the corresponding fields in src.
4431  *
4432  * @return >= 0 on success, a negative AVERROR code on failure.
4433  */
4435 
4436 /**
4437  * Fill the parameters struct based on the values from the supplied codec
4438  * context. Any allocated fields in par are freed and replaced with duplicates
4439  * of the corresponding fields in codec.
4440  *
4441  * @return >= 0 on success, a negative AVERROR code on failure
4442  */
4444  const AVCodecContext *codec);
4445 
4446 /**
4447  * Fill the codec context based on the values from the supplied codec
4448  * parameters. Any allocated fields in codec that have a corresponding field in
4449  * par are freed and replaced with duplicates of the corresponding field in par.
4450  * Fields in codec that do not have a counterpart in par are not touched.
4451  *
4452  * @return >= 0 on success, a negative AVERROR code on failure.
4453  */
4455  const AVCodecParameters *par);
4456 
4457 /**
4458  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4459  * function the context has to be allocated with avcodec_alloc_context3().
4460  *
4461  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4462  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4463  * retrieving a codec.
4464  *
4465  * @warning This function is not thread safe!
4466  *
4467  * @note Always call this function before using decoding routines (such as
4468  * @ref avcodec_receive_frame()).
4469  *
4470  * @code
4471  * avcodec_register_all();
4472  * av_dict_set(&opts, "b", "2.5M", 0);
4473  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4474  * if (!codec)
4475  * exit(1);
4476  *
4477  * context = avcodec_alloc_context3(codec);
4478  *
4479  * if (avcodec_open2(context, codec, opts) < 0)
4480  * exit(1);
4481  * @endcode
4482  *
4483  * @param avctx The context to initialize.
4484  * @param codec The codec to open this context for. If a non-NULL codec has been
4485  * previously passed to avcodec_alloc_context3() or
4486  * for this context, then this parameter MUST be either NULL or
4487  * equal to the previously passed codec.
4488  * @param options A dictionary filled with AVCodecContext and codec-private options.
4489  * On return this object will be filled with options that were not found.
4490  *
4491  * @return zero on success, a negative value on error
4492  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4493  * av_dict_set(), av_opt_find().
4494  */
4495 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4496 
4497 /**
4498  * Close a given AVCodecContext and free all the data associated with it
4499  * (but not the AVCodecContext itself).
4500  *
4501  * Calling this function on an AVCodecContext that hasn't been opened will free
4502  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4503  * codec. Subsequent calls will do nothing.
4504  *
4505  * @note Do not use this function. Use avcodec_free_context() to destroy a
4506  * codec context (either open or closed). Opening and closing a codec context
4507  * multiple times is not supported anymore -- use multiple codec contexts
4508  * instead.
4509  */
4510 int avcodec_close(AVCodecContext *avctx);
4511 
4512 /**
4513  * Free all allocated data in the given subtitle struct.
4514  *
4515  * @param sub AVSubtitle to free.
4516  */
4517 void avsubtitle_free(AVSubtitle *sub);
4518 
4519 /**
4520  * @}
4521  */
4522 
4523 /**
4524  * @addtogroup lavc_packet
4525  * @{
4526  */
4527 
4528 /**
4529  * Allocate an AVPacket and set its fields to default values. The resulting
4530  * struct must be freed using av_packet_free().
4531  *
4532  * @return An AVPacket filled with default values or NULL on failure.
4533  *
4534  * @note this only allocates the AVPacket itself, not the data buffers. Those
4535  * must be allocated through other means such as av_new_packet.
4536  *
4537  * @see av_new_packet
4538  */
4539 AVPacket *av_packet_alloc(void);
4540 
4541 /**
4542  * Create a new packet that references the same data as src.
4543  *
4544  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4545  *
4546  * @return newly created AVPacket on success, NULL on error.
4547  *
4548  * @see av_packet_alloc
4549  * @see av_packet_ref
4550  */
4552 
4553 /**
4554  * Free the packet, if the packet is reference counted, it will be
4555  * unreferenced first.
4556  *
4557  * @param pkt packet to be freed. The pointer will be set to NULL.
4558  * @note passing NULL is a no-op.
4559  */
4560 void av_packet_free(AVPacket **pkt);
4561 
4562 /**
4563  * Initialize optional fields of a packet with default values.
4564  *
4565  * Note, this does not touch the data and size members, which have to be
4566  * initialized separately.
4567  *
4568  * @param pkt packet
4569  */
4570 void av_init_packet(AVPacket *pkt);
4571 
4572 /**
4573  * Allocate the payload of a packet and initialize its fields with
4574  * default values.
4575  *
4576  * @param pkt packet
4577  * @param size wanted payload size
4578  * @return 0 if OK, AVERROR_xxx otherwise
4579  */
4580 int av_new_packet(AVPacket *pkt, int size);
4581 
4582 /**
4583  * Reduce packet size, correctly zeroing padding
4584  *
4585  * @param pkt packet
4586  * @param size new size
4587  */
4588 void av_shrink_packet(AVPacket *pkt, int size);
4589 
4590 /**
4591  * Increase packet size, correctly zeroing padding
4592  *
4593  * @param pkt packet
4594  * @param grow_by number of bytes by which to increase the size of the packet
4595  */
4596 int av_grow_packet(AVPacket *pkt, int grow_by);
4597 
4598 /**
4599  * Initialize a reference-counted packet from av_malloc()ed data.
4600  *
4601  * @param pkt packet to be initialized. This function will set the data, size,
4602  * buf and destruct fields, all others are left untouched.
4603  * @param data Data allocated by av_malloc() to be used as packet data. If this
4604  * function returns successfully, the data is owned by the underlying AVBuffer.
4605  * The caller may not access the data through other means.
4606  * @param size size of data in bytes, without the padding. I.e. the full buffer
4607  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4608  *
4609  * @return 0 on success, a negative AVERROR on error
4610  */
4612 
4613 #if FF_API_AVPACKET_OLD_API
4614 /**
4615  * @warning This is a hack - the packet memory allocation stuff is broken. The
4616  * packet is allocated if it was not really allocated.
4617  *
4618  * @deprecated Use av_packet_ref
4619  */
4621 int av_dup_packet(AVPacket *pkt);
4622 /**
4623  * Copy packet, including contents
4624  *
4625  * @return 0 on success, negative AVERROR on fail
4626  *
4627  * @deprecated Use av_packet_ref
4628  */
4630 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4631 
4632 /**
4633  * Copy packet side data
4634  *
4635  * @return 0 on success, negative AVERROR on fail
4636  *
4637  * @deprecated Use av_packet_copy_props
4638  */
4640 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4641 
4642 /**
4643  * Free a packet.
4644  *
4645  * @deprecated Use av_packet_unref
4646  *
4647  * @param pkt packet to free
4648  */
4650 void av_free_packet(AVPacket *pkt);
4651 #endif
4652 /**
4653  * Allocate new information of a packet.
4654  *
4655  * @param pkt packet
4656  * @param type side information type
4657  * @param size side information size
4658  * @return pointer to fresh allocated data or NULL otherwise
4659  */
4661  int size);
4662 
4663 /**
4664  * Wrap an existing array as a packet side data.
4665  *
4666  * @param pkt packet
4667  * @param type side information type
4668  * @param data the side data array. It must be allocated with the av_malloc()
4669  * family of functions. The ownership of the data is transferred to
4670  * pkt.
4671  * @param size side information size
4672  * @return a non-negative number on success, a negative AVERROR code on
4673  * failure. On failure, the packet is unchanged and the data remains
4674  * owned by the caller.
4675  */
4677  uint8_t *data, size_t size);
4678 
4679 /**
4680  * Shrink the already allocated side data buffer
4681  *
4682  * @param pkt packet
4683  * @param type side information type
4684  * @param size new side information size
4685  * @return 0 on success, < 0 on failure
4686  */
4688  int size);
4689 
4690 /**
4691  * Get side information from packet.
4692  *
4693  * @param pkt packet
4694  * @param type desired side information type
4695  * @param size pointer for side information size to store (optional)
4696  * @return pointer to data if present or NULL otherwise
4697  */
4699  int *size);
4700 
4701 #if FF_API_MERGE_SD_API
4704 
4707 #endif
4708 
4710 
4711 /**
4712  * Pack a dictionary for use in side_data.
4713  *
4714  * @param dict The dictionary to pack.
4715  * @param size pointer to store the size of the returned data
4716  * @return pointer to data if successful, NULL otherwise
4717  */
4719 /**
4720  * Unpack a dictionary from side_data.
4721  *
4722  * @param data data from side_data
4723  * @param size size of the data
4724  * @param dict the metadata storage dictionary
4725  * @return 0 on success, < 0 on failure
4726  */
4727 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4728 
4729 
4730 /**
4731  * Convenience function to free all the side data stored.
4732  * All the other fields stay untouched.
4733  *
4734  * @param pkt packet
4735  */
4737 
4738 /**
4739  * Setup a new reference to the data described by a given packet
4740  *
4741  * If src is reference-counted, setup dst as a new reference to the
4742  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4743  * data from src into it.
4744  *
4745  * All the other fields are copied from src.
4746  *
4747  * @see av_packet_unref
4748  *
4749  * @param dst Destination packet
4750  * @param src Source packet
4751  *
4752  * @return 0 on success, a negative AVERROR on error.
4753  */
4754 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4755 
4756 /**
4757  * Wipe the packet.
4758  *
4759  * Unreference the buffer referenced by the packet and reset the
4760  * remaining packet fields to their default values.
4761  *
4762  * @param pkt The packet to be unreferenced.
4763  */
4765 
4766 /**
4767  * Move every field in src to dst and reset src.
4768  *
4769  * @see av_packet_unref
4770  *
4771  * @param src Source packet, will be reset
4772  * @param dst Destination packet
4773  */
4775 
4776 /**
4777  * Copy only "properties" fields from src to dst.
4778  *
4779  * Properties for the purpose of this function are all the fields
4780  * beside those related to the packet data (buf, data, size)
4781  *
4782  * @param dst Destination packet
4783  * @param src Source packet
4784  *
4785  * @return 0 on success AVERROR on failure.
4786  */
4787 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4788 
4789 /**
4790  * Convert valid timing fields (timestamps / durations) in a packet from one
4791  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4792  * ignored.
4793  *
4794  * @param pkt packet on which the conversion will be performed
4795  * @param tb_src source timebase, in which the timing fields in pkt are
4796  * expressed
4797  * @param tb_dst destination timebase, to which the timing fields will be
4798  * converted
4799  */
4800 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4801 
4802 /**
4803  * @}
4804  */
4805 
4806 /**
4807  * @addtogroup lavc_decoding
4808  * @{
4809  */
4810 
4811 /**
4812  * Find a registered decoder with a matching codec ID.
4813  *
4814  * @param id AVCodecID of the requested decoder
4815  * @return A decoder if one was found, NULL otherwise.
4816  */
4818 
4819 /**
4820  * Find a registered decoder with the specified name.
4821  *
4822  * @param name name of the requested decoder
4823  * @return A decoder if one was found, NULL otherwise.
4824  */
4826 
4827 /**
4828  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4829  * it can be called by custom get_buffer2() implementations for decoders without
4830  * AV_CODEC_CAP_DR1 set.
4831  */
4833 
4834 #if FF_API_EMU_EDGE
4835 /**
4836  * Return the amount of padding in pixels which the get_buffer callback must
4837  * provide around the edge of the image for codecs which do not have the
4838  * CODEC_FLAG_EMU_EDGE flag.
4839  *
4840  * @return Required padding in pixels.
4841  *
4842  * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
4843  * needed
4844  */
4846 unsigned avcodec_get_edge_width(void);
4847 #endif
4848 
4849 /**
4850  * Modify width and height values so that they will result in a memory
4851  * buffer that is acceptable for the codec if you do not use any horizontal
4852  * padding.
4853  *
4854  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4855  */
4857 
4858 /**
4859  * Modify width and height values so that they will result in a memory
4860  * buffer that is acceptable for the codec if you also ensure that all
4861  * line sizes are a multiple of the respective linesize_align[i].
4862  *
4863  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4864  */
4866  int linesize_align[AV_NUM_DATA_POINTERS]);
4867 
4868 /**
4869  * Converts AVChromaLocation to swscale x/y chroma position.
4870  *
4871  * The positions represent the chroma (0,0) position in a coordinates system
4872  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4873  *
4874  * @param xpos horizontal chroma sample position
4875  * @param ypos vertical chroma sample position
4876  */
4877 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4878 
4879 /**
4880  * Converts swscale x/y chroma position to AVChromaLocation.
4881  *
4882  * The positions represent the chroma (0,0) position in a coordinates system
4883  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4884  *
4885  * @param xpos horizontal chroma sample position
4886  * @param ypos vertical chroma sample position
4887  */
4888 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4889 
4890 /**
4891  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4892  *
4893  * Some decoders may support multiple frames in a single AVPacket. Such
4894  * decoders would then just decode the first frame and the return value would be
4895  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4896  * called again with an AVPacket containing the remaining data in order to
4897  * decode the second frame, etc... Even if no frames are returned, the packet
4898  * needs to be fed to the decoder with remaining data until it is completely
4899  * consumed or an error occurs.
4900  *
4901  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4902  * and output. This means that for some packets they will not immediately
4903  * produce decoded output and need to be flushed at the end of decoding to get
4904  * all the decoded data. Flushing is done by calling this function with packets
4905  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4906  * returning samples. It is safe to flush even those decoders that are not
4907  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4908  *
4909  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4910  * larger than the actual read bytes because some optimized bitstream
4911  * readers read 32 or 64 bits at once and could read over the end.
4912  *
4913  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4914  * before packets may be fed to the decoder.
4915  *
4916  * @param avctx the codec context
4917  * @param[out] frame The AVFrame in which to store decoded audio samples.
4918  * The decoder will allocate a buffer for the decoded frame by
4919  * calling the AVCodecContext.get_buffer2() callback.
4920  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4921  * reference counted and the returned reference belongs to the
4922  * caller. The caller must release the frame using av_frame_unref()
4923  * when the frame is no longer needed. The caller may safely write
4924  * to the frame if av_frame_is_writable() returns 1.
4925  * When AVCodecContext.refcounted_frames is set to 0, the returned
4926  * reference belongs to the decoder and is valid only until the
4927  * next call to this function or until closing or flushing the
4928  * decoder. The caller may not write to it.
4929  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4930  * non-zero. Note that this field being set to zero
4931  * does not mean that an error has occurred. For
4932  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4933  * call is guaranteed to produce a frame.
4934  * @param[in] avpkt The input AVPacket containing the input buffer.
4935  * At least avpkt->data and avpkt->size should be set. Some
4936  * decoders might also require additional fields to be set.
4937  * @return A negative error code is returned if an error occurred during
4938  * decoding, otherwise the number of bytes consumed from the input
4939  * AVPacket is returned.
4940  *
4941 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4942  */
4945  int *got_frame_ptr, const AVPacket *avpkt);
4946 
4947 /**
4948  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4949  * Some decoders may support multiple frames in a single AVPacket, such
4950  * decoders would then just decode the first frame.
4951  *
4952  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4953  * the actual read bytes because some optimized bitstream readers read 32 or 64
4954  * bits at once and could read over the end.
4955  *
4956  * @warning The end of the input buffer buf should be set to 0 to ensure that
4957  * no overreading happens for damaged MPEG streams.
4958  *
4959  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4960  * between input and output, these need to be fed with avpkt->data=NULL,
4961  * avpkt->size=0 at the end to return the remaining frames.
4962  *
4963  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4964  * before packets may be fed to the decoder.
4965  *
4966  * @param avctx the codec context
4967  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4968  * Use av_frame_alloc() to get an AVFrame. The codec will
4969  * allocate memory for the actual bitmap by calling the
4970  * AVCodecContext.get_buffer2() callback.
4971  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4972  * reference counted and the returned reference belongs to the
4973  * caller. The caller must release the frame using av_frame_unref()
4974  * when the frame is no longer needed. The caller may safely write
4975  * to the frame if av_frame_is_writable() returns 1.
4976  * When AVCodecContext.refcounted_frames is set to 0, the returned
4977  * reference belongs to the decoder and is valid only until the
4978  * next call to this function or until closing or flushing the
4979  * decoder. The caller may not write to it.
4980  *
4981  * @param[in] avpkt The input AVPacket containing the input buffer.
4982  * You can create such packet with av_init_packet() and by then setting
4983  * data and size, some decoders might in addition need other fields like
4984  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4985  * fields possible.
4986  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4987  * @return On error a negative value is returned, otherwise the number of bytes
4988  * used or zero if no frame could be decompressed.
4989  *
4990  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4991  */
4993 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4994  int *got_picture_ptr,
4995  const AVPacket *avpkt);
4996 
4997 /**
4998  * Decode a subtitle message.
4999  * Return a negative value on error, otherwise return the number of bytes used.
5000  * If no subtitle could be decompressed, got_sub_ptr is zero.
5001  * Otherwise, the subtitle is stored in *sub.
5002  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
5003  * simplicity, because the performance difference is expect to be negligible
5004  * and reusing a get_buffer written for video codecs would probably perform badly
5005  * due to a potentially very different allocation pattern.
5006  *
5007  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
5008  * and output. This means that for some packets they will not immediately
5009  * produce decoded output and need to be flushed at the end of decoding to get
5010  * all the decoded data. Flushing is done by calling this function with packets
5011  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
5012  * returning subtitles. It is safe to flush even those decoders that are not
5013  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
5014  *
5015  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
5016  * before packets may be fed to the decoder.
5017  *
5018  * @param avctx the codec context
5019  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
5020  * must be freed with avsubtitle_free if *got_sub_ptr is set.
5021  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
5022  * @param[in] avpkt The input AVPacket containing the input buffer.
5023  */
5025  int *got_sub_ptr,
5026  AVPacket *avpkt);
5027 
5028 /**
5029  * Supply raw packet data as input to a decoder.
5030  *
5031  * Internally, this call will copy relevant AVCodecContext fields, which can
5032  * influence decoding per-packet, and apply them when the packet is actually
5033  * decoded. (For example AVCodecContext.skip_frame, which might direct the
5034  * decoder to drop the frame contained by the packet sent with this function.)
5035  *
5036  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
5037  * larger than the actual read bytes because some optimized bitstream
5038  * readers read 32 or 64 bits at once and could read over the end.
5039  *
5040  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
5041  * on the same AVCodecContext. It will return unexpected results now
5042  * or in future libavcodec versions.
5043  *
5044  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
5045  * before packets may be fed to the decoder.
5046  *
5047  * @param avctx codec context
5048  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
5049  * frame, or several complete audio frames.
5050  * Ownership of the packet remains with the caller, and the
5051  * decoder will not write to the packet. The decoder may create
5052  * a reference to the packet data (or copy it if the packet is
5053  * not reference-counted).
5054  * Unlike with older APIs, the packet is always fully consumed,
5055  * and if it contains multiple frames (e.g. some audio codecs),
5056  * will require you to call avcodec_receive_frame() multiple
5057  * times afterwards before you can send a new packet.
5058  * It can be NULL (or an AVPacket with data set to NULL and
5059  * size set to 0); in this case, it is considered a flush
5060  * packet, which signals the end of the stream. Sending the
5061  * first flush packet will return success. Subsequent ones are
5062  * unnecessary and will return AVERROR_EOF. If the decoder
5063  * still has frames buffered, it will return them after sending
5064  * a flush packet.
5065  *
5066  * @return 0 on success, otherwise negative error code:
5067  * AVERROR(EAGAIN): input is not accepted in the current state - user
5068  * must read output with avcodec_receive_frame() (once
5069  * all output is read, the packet should be resent, and
5070  * the call will not fail with EAGAIN).
5071  * AVERROR_EOF: the decoder has been flushed, and no new packets can
5072  * be sent to it (also returned if more than 1 flush
5073  * packet is sent)
5074  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
5075  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
5076  * other errors: legitimate decoding errors
5077  */
5078 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
5079 
5080 /**
5081  * Return decoded output data from a decoder.
5082  *
5083  * @param avctx codec context
5084  * @param frame This will be set to a reference-counted video or audio
5085  * frame (depending on the decoder type) allocated by the
5086  * decoder. Note that the function will always call
5087  * av_frame_unref(frame) before doing anything else.
5088  *
5089  * @return
5090  * 0: success, a frame was returned
5091  * AVERROR(EAGAIN): output is not available in this state - user must try
5092  * to send new input
5093  * AVERROR_EOF: the decoder has been fully flushed, and there will be
5094  * no more output frames
5095  * AVERROR(EINVAL): codec not opened, or it is an encoder
5096  * other negative values: legitimate decoding errors
5097  */
5099 
5100 /**
5101  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
5102  * to retrieve buffered output packets.
5103  *
5104  * @param avctx codec context
5105  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
5106  * Ownership of the frame remains with the caller, and the
5107  * encoder will not write to the frame. The encoder may create
5108  * a reference to the frame data (or copy it if the frame is
5109  * not reference-counted).
5110  * It can be NULL, in which case it is considered a flush
5111  * packet. This signals the end of the stream. If the encoder
5112  * still has packets buffered, it will return them after this
5113  * call. Once flushing mode has been entered, additional flush
5114  * packets are ignored, and sending frames will return
5115  * AVERROR_EOF.
5116  *
5117  * For audio:
5118  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5119  * can have any number of samples.
5120  * If it is not set, frame->nb_samples must be equal to
5121  * avctx->frame_size for all frames except the last.
5122  * The final frame may be smaller than avctx->frame_size.
5123  * @return 0 on success, otherwise negative error code:
5124  * AVERROR(EAGAIN): input is not accepted in the current state - user
5125  * must read output with avcodec_receive_packet() (once
5126  * all output is read, the packet should be resent, and
5127  * the call will not fail with EAGAIN).
5128  * AVERROR_EOF: the encoder has been flushed, and no new frames can
5129  * be sent to it
5130  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
5131  * decoder, or requires flush
5132  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
5133  * other errors: legitimate decoding errors
5134  */
5135 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
5136 
5137 /**
5138  * Read encoded data from the encoder.
5139  *
5140  * @param avctx codec context
5141  * @param avpkt This will be set to a reference-counted packet allocated by the
5142  * encoder. Note that the function will always call
5143  * av_frame_unref(frame) before doing anything else.
5144  * @return 0 on success, otherwise negative error code:
5145  * AVERROR(EAGAIN): output is not available in the current state - user
5146  * must try to send input
5147  * AVERROR_EOF: the encoder has been fully flushed, and there will be
5148  * no more output packets
5149  * AVERROR(EINVAL): codec not opened, or it is an encoder
5150  * other errors: legitimate decoding errors
5151  */
5152 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
5153 
5154 
5155 /**
5156  * @defgroup lavc_parsing Frame parsing
5157  * @{
5158  */
5159 
5162  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5163  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5164  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5165 };
5166 
5167 typedef struct AVCodecParserContext {
5168  void *priv_data;
5170  int64_t frame_offset; /* offset of the current frame */
5171  int64_t cur_offset; /* current offset
5172  (incremented by each av_parser_parse()) */
5173  int64_t next_frame_offset; /* offset of the next frame */
5174  /* video info */
5175  int pict_type; /* XXX: Put it back in AVCodecContext. */
5176  /**
5177  * This field is used for proper frame duration computation in lavf.
5178  * It signals, how much longer the frame duration of the current frame
5179  * is compared to normal frame duration.
5180  *
5181  * frame_duration = (1 + repeat_pict) * time_base
5182  *
5183  * It is used by codecs like H.264 to display telecined material.
5184  */
5185  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5186  int64_t pts; /* pts of the current frame */
5187  int64_t dts; /* dts of the current frame */
5188 
5189  /* private data */
5190  int64_t last_pts;
5191  int64_t last_dts;
5193 
5194 #define AV_PARSER_PTS_NB 4
5199 
5200  int flags;
5201 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5202 #define PARSER_FLAG_ONCE 0x0002
5203 /// Set if the parser has a valid file offset
5204 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5205 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5206 
5207  int64_t offset; ///< byte offset from starting packet start
5209 
5210  /**
5211  * Set by parser to 1 for key frames and 0 for non-key frames.
5212  * It is initialized to -1, so if the parser doesn't set this flag,
5213  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5214  * will be used.
5215  */
5217 
5218 #if FF_API_CONVERGENCE_DURATION
5219  /**
5220  * @deprecated unused
5221  */
5224 #endif
5225 
5226  // Timestamp generation support:
5227  /**
5228  * Synchronization point for start of timestamp generation.
5229  *
5230  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5231  * (default).
5232  *
5233  * For example, this corresponds to presence of H.264 buffering period
5234  * SEI message.
5235  */
5237 
5238  /**
5239  * Offset of the current timestamp against last timestamp sync point in
5240  * units of AVCodecContext.time_base.
5241  *
5242  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5243  * contain a valid timestamp offset.
5244  *
5245  * Note that the timestamp of sync point has usually a nonzero
5246  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5247  * the next frame after timestamp sync point will be usually 1.
5248  *
5249  * For example, this corresponds to H.264 cpb_removal_delay.
5250  */
5252 
5253  /**
5254  * Presentation delay of current frame in units of AVCodecContext.time_base.
5255  *
5256  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5257  * contain valid non-negative timestamp delta (presentation time of a frame
5258  * must not lie in the past).
5259  *
5260  * This delay represents the difference between decoding and presentation
5261  * time of the frame.
5262  *
5263  * For example, this corresponds to H.264 dpb_output_delay.
5264  */
5266 
5267  /**
5268  * Position of the packet in file.
5269  *
5270  * Analogous to cur_frame_pts/dts
5271  */
5273 
5274  /**
5275  * Byte position of currently parsed frame in stream.
5276  */
5277  int64_t pos;
5278 
5279  /**
5280  * Previous frame byte position.
5281  */
5282  int64_t last_pos;
5283 
5284  /**
5285  * Duration of the current frame.
5286  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5287  * For all other types, this is in units of AVCodecContext.time_base.
5288  */
5290 
5292 
5293  /**
5294  * Indicate whether a picture is coded as a frame, top field or bottom field.
5295  *
5296  * For example, H.264 field_pic_flag equal to 0 corresponds to
5297  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5298  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5299  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5300  */
5302 
5303  /**
5304  * Picture number incremented in presentation or output order.
5305  * This field may be reinitialized at the first picture of a new sequence.
5306  *
5307  * For example, this corresponds to H.264 PicOrderCnt.
5308  */
5310 
5311  /**
5312  * Dimensions of the decoded video intended for presentation.
5313  */
5314  int width;