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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 
448 
449  /* various PCM "codecs" */
450  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
482 
487 
488  /* various ADPCM codecs */
520 #if FF_API_VIMA_DECODER
522 #endif
523 
534 
535  /* AMR */
538 
539  /* RealAudio codecs*/
542 
543  /* various DPCM codecs */
548 
550 
551  /* audio codecs */
552  AV_CODEC_ID_MP2 = 0x15000,
553  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
570  AV_CODEC_ID_GSM, ///< as in Berlin toast format
582  AV_CODEC_ID_GSM_MS, /* as found in WAV */
584 #if FF_API_VOXWARE
586 #endif
622 
639 
640  /* subtitle codecs */
641  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
644  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
651 
667 
668  /* other specific kind of codecs (generally used for attachments) */
669  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
670  AV_CODEC_ID_TTF = 0x18000,
671 
672  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
681 
682 
683  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
684 
685  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
686  * stream (only used by libavformat) */
687  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
688  * stream (only used by libavformat) */
689  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
690  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
691 };
692 
693 /**
694  * This struct describes the properties of a single codec described by an
695  * AVCodecID.
696  * @see avcodec_descriptor_get()
697  */
698 typedef struct AVCodecDescriptor {
699  enum AVCodecID id;
701  /**
702  * Name of the codec described by this descriptor. It is non-empty and
703  * unique for each codec descriptor. It should contain alphanumeric
704  * characters and '_' only.
705  */
706  const char *name;
707  /**
708  * A more descriptive name for this codec. May be NULL.
709  */
710  const char *long_name;
711  /**
712  * Codec properties, a combination of AV_CODEC_PROP_* flags.
713  */
714  int props;
715  /**
716  * MIME type(s) associated with the codec.
717  * May be NULL; if not, a NULL-terminated array of MIME types.
718  * The first item is always non-NULL and is the preferred MIME type.
719  */
720  const char *const *mime_types;
721  /**
722  * If non-NULL, an array of profiles recognized for this codec.
723  * Terminated with FF_PROFILE_UNKNOWN.
724  */
725  const struct AVProfile *profiles;
727 
728 /**
729  * Codec uses only intra compression.
730  * Video and audio codecs only.
731  */
732 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
733 /**
734  * Codec supports lossy compression. Audio and video codecs only.
735  * @note a codec may support both lossy and lossless
736  * compression modes
737  */
738 #define AV_CODEC_PROP_LOSSY (1 << 1)
739 /**
740  * Codec supports lossless compression. Audio and video codecs only.
741  */
742 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
743 /**
744  * Codec supports frame reordering. That is, the coded order (the order in which
745  * the encoded packets are output by the encoders / stored / input to the
746  * decoders) may be different from the presentation order of the corresponding
747  * frames.
748  *
749  * For codecs that do not have this property set, PTS and DTS should always be
750  * equal.
751  */
752 #define AV_CODEC_PROP_REORDER (1 << 3)
753 /**
754  * Subtitle codec is bitmap based
755  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
756  */
757 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
758 /**
759  * Subtitle codec is text based.
760  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
761  */
762 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
763 
764 /**
765  * @ingroup lavc_decoding
766  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
767  * This is mainly needed because some optimized bitstream readers read
768  * 32 or 64 bit at once and could read over the end.<br>
769  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
770  * MPEG bitstreams could cause overread and segfault.
771  */
772 #define AV_INPUT_BUFFER_PADDING_SIZE 32
773 
774 /**
775  * @ingroup lavc_encoding
776  * minimum encoding buffer size
777  * Used to avoid some checks during header writing.
778  */
779 #define AV_INPUT_BUFFER_MIN_SIZE 16384
780 
781 #if FF_API_WITHOUT_PREFIX
782 /**
783  * @deprecated use AV_INPUT_BUFFER_PADDING_SIZE instead
784  */
785 #define FF_INPUT_BUFFER_PADDING_SIZE 32
786 
787 /**
788  * @deprecated use AV_INPUT_BUFFER_MIN_SIZE instead
789  */
790 #define FF_MIN_BUFFER_SIZE 16384
791 #endif /* FF_API_WITHOUT_PREFIX */
792 
793 /**
794  * @ingroup lavc_encoding
795  * motion estimation type.
796  * @deprecated use codec private option instead
797  */
798 #if FF_API_MOTION_EST
800  ME_ZERO = 1, ///< no search, that is use 0,0 vector whenever one is needed
804  ME_EPZS, ///< enhanced predictive zonal search
805  ME_X1, ///< reserved for experiments
806  ME_HEX, ///< hexagon based search
807  ME_UMH, ///< uneven multi-hexagon search
808  ME_TESA, ///< transformed exhaustive search algorithm
809  ME_ITER=50, ///< iterative search
810 };
811 #endif
812 
813 /**
814  * @ingroup lavc_decoding
815  */
817  /* We leave some space between them for extensions (drop some
818  * keyframes for intra-only or drop just some bidir frames). */
819  AVDISCARD_NONE =-16, ///< discard nothing
820  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
821  AVDISCARD_NONREF = 8, ///< discard all non reference
822  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
823  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
824  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
825  AVDISCARD_ALL = 48, ///< discard all
826 };
827 
838  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
839 };
840 
841 /**
842  * @ingroup lavc_encoding
843  */
844 typedef struct RcOverride{
847  int qscale; // If this is 0 then quality_factor will be used instead.
849 } RcOverride;
850 
851 #if FF_API_MAX_BFRAMES
852 /**
853  * @deprecated there is no libavcodec-wide limit on the number of B-frames
854  */
855 #define FF_MAX_B_FRAMES 16
856 #endif
857 
858 /* encoding support
859  These flags can be passed in AVCodecContext.flags before initialization.
860  Note: Not everything is supported yet.
861 */
862 
863 /**
864  * Allow decoders to produce frames with data planes that are not aligned
865  * to CPU requirements (e.g. due to cropping).
866  */
867 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
868 /**
869  * Use fixed qscale.
870  */
871 #define AV_CODEC_FLAG_QSCALE (1 << 1)
872 /**
873  * 4 MV per MB allowed / advanced prediction for H.263.
874  */
875 #define AV_CODEC_FLAG_4MV (1 << 2)
876 /**
877  * Output even those frames that might be corrupted.
878  */
879 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
880 /**
881  * Use qpel MC.
882  */
883 #define AV_CODEC_FLAG_QPEL (1 << 4)
884 /**
885  * Use internal 2pass ratecontrol in first pass mode.
886  */
887 #define AV_CODEC_FLAG_PASS1 (1 << 9)
888 /**
889  * Use internal 2pass ratecontrol in second pass mode.
890  */
891 #define AV_CODEC_FLAG_PASS2 (1 << 10)
892 /**
893  * loop filter.
894  */
895 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
896 /**
897  * Only decode/encode grayscale.
898  */
899 #define AV_CODEC_FLAG_GRAY (1 << 13)
900 /**
901  * error[?] variables will be set during encoding.
902  */
903 #define AV_CODEC_FLAG_PSNR (1 << 15)
904 /**
905  * Input bitstream might be truncated at a random location
906  * instead of only at frame boundaries.
907  */
908 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
909 /**
910  * Use interlaced DCT.
911  */
912 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
913 /**
914  * Force low delay.
915  */
916 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
917 /**
918  * Place global headers in extradata instead of every keyframe.
919  */
920 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
921 /**
922  * Use only bitexact stuff (except (I)DCT).
923  */
924 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
925 /* Fx : Flag for H.263+ extra options */
926 /**
927  * H.263 advanced intra coding / MPEG-4 AC prediction
928  */
929 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
930 /**
931  * interlaced motion estimation
932  */
933 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
934 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
935 
936 /**
937  * Allow non spec compliant speedup tricks.
938  */
939 #define AV_CODEC_FLAG2_FAST (1 << 0)
940 /**
941  * Skip bitstream encoding.
942  */
943 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
944 /**
945  * Place global headers at every keyframe instead of in extradata.
946  */
947 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
948 
949 /**
950  * timecode is in drop frame format. DEPRECATED!!!!
951  */
952 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
953 
954 /**
955  * Input bitstream might be truncated at a packet boundaries
956  * instead of only at frame boundaries.
957  */
958 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
959 /**
960  * Discard cropping information from SPS.
961  */
962 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
963 
964 /**
965  * Show all frames before the first keyframe
966  */
967 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
968 /**
969  * Export motion vectors through frame side data
970  */
971 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
972 /**
973  * Do not skip samples and export skip information as frame side data
974  */
975 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
976 /**
977  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
978  */
979 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
980 
981 /* Unsupported options :
982  * Syntax Arithmetic coding (SAC)
983  * Reference Picture Selection
984  * Independent Segment Decoding */
985 /* /Fx */
986 /* codec capabilities */
987 
988 /**
989  * Decoder can use draw_horiz_band callback.
990  */
991 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
992 /**
993  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
994  * If not set, it might not use get_buffer() at all or use operations that
995  * assume the buffer was allocated by avcodec_default_get_buffer.
996  */
997 #define AV_CODEC_CAP_DR1 (1 << 1)
998 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
999 /**
1000  * Encoder or decoder requires flushing with NULL input at the end in order to
1001  * give the complete and correct output.
1002  *
1003  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
1004  * with NULL data. The user can still send NULL data to the public encode
1005  * or decode function, but libavcodec will not pass it along to the codec
1006  * unless this flag is set.
1007  *
1008  * Decoders:
1009  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
1010  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
1011  * returns frames.
1012  *
1013  * Encoders:
1014  * The encoder needs to be fed with NULL data at the end of encoding until the
1015  * encoder no longer returns data.
1016  *
1017  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1018  * flag also means that the encoder must set the pts and duration for
1019  * each output packet. If this flag is not set, the pts and duration will
1020  * be determined by libavcodec from the input frame.
1021  */
1022 #define AV_CODEC_CAP_DELAY (1 << 5)
1023 /**
1024  * Codec can be fed a final frame with a smaller size.
1025  * This can be used to prevent truncation of the last audio samples.
1026  */
1027 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
1028 
1029 #if FF_API_CAP_VDPAU
1030 /**
1031  * Codec can export data for HW decoding (VDPAU).
1032  */
1033 #define AV_CODEC_CAP_HWACCEL_VDPAU (1 << 7)
1034 #endif
1035 
1036 /**
1037  * Codec can output multiple frames per AVPacket
1038  * Normally demuxers return one frame at a time, demuxers which do not do
1039  * are connected to a parser to split what they return into proper frames.
1040  * This flag is reserved to the very rare category of codecs which have a
1041  * bitstream that cannot be split into frames without timeconsuming
1042  * operations like full decoding. Demuxers carrying such bitstreams thus
1043  * may return multiple frames in a packet. This has many disadvantages like
1044  * prohibiting stream copy in many cases thus it should only be considered
1045  * as a last resort.
1046  */
1047 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1048 /**
1049  * Codec is experimental and is thus avoided in favor of non experimental
1050  * encoders
1051  */
1052 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1053 /**
1054  * Codec should fill in channel configuration and samplerate instead of container
1055  */
1056 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1057 /**
1058  * Codec supports frame-level multithreading.
1059  */
1060 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1061 /**
1062  * Codec supports slice-based (or partition-based) multithreading.
1063  */
1064 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1065 /**
1066  * Codec supports changed parameters at any point.
1067  */
1068 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1069 /**
1070  * Codec supports avctx->thread_count == 0 (auto).
1071  */
1072 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1073 /**
1074  * Audio encoder supports receiving a different number of samples in each call.
1075  */
1076 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1077 /**
1078  * Decoder is not a preferred choice for probing.
1079  * This indicates that the decoder is not a good choice for probing.
1080  * It could for example be an expensive to spin up hardware decoder,
1081  * or it could simply not provide a lot of useful information about
1082  * the stream.
1083  * A decoder marked with this flag should only be used as last resort
1084  * choice for probing.
1085  */
1086 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1087 /**
1088  * Codec is intra only.
1089  */
1090 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1091 /**
1092  * Codec is lossless.
1093  */
1094 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1095 
1096 
1097 #if FF_API_WITHOUT_PREFIX
1098 /**
1099  * Allow decoders to produce frames with data planes that are not aligned
1100  * to CPU requirements (e.g. due to cropping).
1101  */
1102 #define CODEC_FLAG_UNALIGNED AV_CODEC_FLAG_UNALIGNED
1103 #define CODEC_FLAG_QSCALE AV_CODEC_FLAG_QSCALE
1104 #define CODEC_FLAG_4MV AV_CODEC_FLAG_4MV
1105 #define CODEC_FLAG_OUTPUT_CORRUPT AV_CODEC_FLAG_OUTPUT_CORRUPT
1106 #define CODEC_FLAG_QPEL AV_CODEC_FLAG_QPEL
1107 #if FF_API_GMC
1108 /**
1109  * @deprecated use the "gmc" private option of the libxvid encoder
1110  */
1111 #define CODEC_FLAG_GMC 0x0020 ///< Use GMC.
1112 #endif
1113 #if FF_API_MV0
1114 /**
1115  * @deprecated use the flag "mv0" in the "mpv_flags" private option of the
1116  * mpegvideo encoders
1117  */
1118 #define CODEC_FLAG_MV0 0x0040
1119 #endif
1120 #if FF_API_INPUT_PRESERVED
1121 /**
1122  * @deprecated passing reference-counted frames to the encoders replaces this
1123  * flag
1124  */
1125 #define CODEC_FLAG_INPUT_PRESERVED 0x0100
1126 #endif
1127 #define CODEC_FLAG_PASS1 AV_CODEC_FLAG_PASS1
1128 #define CODEC_FLAG_PASS2 AV_CODEC_FLAG_PASS2
1129 #define CODEC_FLAG_GRAY AV_CODEC_FLAG_GRAY
1130 #if FF_API_EMU_EDGE
1131 /**
1132  * @deprecated edges are not used/required anymore. I.e. this flag is now always
1133  * set.
1134  */
1135 #define CODEC_FLAG_EMU_EDGE 0x4000
1136 #endif
1137 #define CODEC_FLAG_PSNR AV_CODEC_FLAG_PSNR
1138 #define CODEC_FLAG_TRUNCATED AV_CODEC_FLAG_TRUNCATED
1139 
1140 #if FF_API_NORMALIZE_AQP
1141 /**
1142  * @deprecated use the flag "naq" in the "mpv_flags" private option of the
1143  * mpegvideo encoders
1144  */
1145 #define CODEC_FLAG_NORMALIZE_AQP 0x00020000
1146 #endif
1147 #define CODEC_FLAG_INTERLACED_DCT AV_CODEC_FLAG_INTERLACED_DCT
1148 #define CODEC_FLAG_LOW_DELAY AV_CODEC_FLAG_LOW_DELAY
1149 #define CODEC_FLAG_GLOBAL_HEADER AV_CODEC_FLAG_GLOBAL_HEADER
1150 #define CODEC_FLAG_BITEXACT AV_CODEC_FLAG_BITEXACT
1151 #define CODEC_FLAG_AC_PRED AV_CODEC_FLAG_AC_PRED
1152 #define CODEC_FLAG_LOOP_FILTER AV_CODEC_FLAG_LOOP_FILTER
1153 #define CODEC_FLAG_INTERLACED_ME AV_CODEC_FLAG_INTERLACED_ME
1154 #define CODEC_FLAG_CLOSED_GOP AV_CODEC_FLAG_CLOSED_GOP
1155 #define CODEC_FLAG2_FAST AV_CODEC_FLAG2_FAST
1156 #define CODEC_FLAG2_NO_OUTPUT AV_CODEC_FLAG2_NO_OUTPUT
1157 #define CODEC_FLAG2_LOCAL_HEADER AV_CODEC_FLAG2_LOCAL_HEADER
1158 #define CODEC_FLAG2_DROP_FRAME_TIMECODE AV_CODEC_FLAG2_DROP_FRAME_TIMECODE
1159 #define CODEC_FLAG2_IGNORE_CROP AV_CODEC_FLAG2_IGNORE_CROP
1160 
1161 #define CODEC_FLAG2_CHUNKS AV_CODEC_FLAG2_CHUNKS
1162 #define CODEC_FLAG2_SHOW_ALL AV_CODEC_FLAG2_SHOW_ALL
1163 #define CODEC_FLAG2_EXPORT_MVS AV_CODEC_FLAG2_EXPORT_MVS
1164 #define CODEC_FLAG2_SKIP_MANUAL AV_CODEC_FLAG2_SKIP_MANUAL
1165 
1166 /* Unsupported options :
1167  * Syntax Arithmetic coding (SAC)
1168  * Reference Picture Selection
1169  * Independent Segment Decoding */
1170 /* /Fx */
1171 /* codec capabilities */
1172 
1173 #define CODEC_CAP_DRAW_HORIZ_BAND AV_CODEC_CAP_DRAW_HORIZ_BAND ///< Decoder can use draw_horiz_band callback.
1174 /**
1175  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
1176  * If not set, it might not use get_buffer() at all or use operations that
1177  * assume the buffer was allocated by avcodec_default_get_buffer.
1178  */
1179 #define CODEC_CAP_DR1 AV_CODEC_CAP_DR1
1180 #define CODEC_CAP_TRUNCATED AV_CODEC_CAP_TRUNCATED
1181 #if FF_API_XVMC
1182 /* Codec can export data for HW decoding. This flag indicates that
1183  * the codec would call get_format() with list that might contain HW accelerated
1184  * pixel formats (XvMC, VDPAU, VAAPI, etc). The application can pick any of them
1185  * including raw image format.
1186  * The application can use the passed context to determine bitstream version,
1187  * chroma format, resolution etc.
1188  */
1189 #define CODEC_CAP_HWACCEL 0x0010
1190 #endif /* FF_API_XVMC */
1191 /**
1192  * Encoder or decoder requires flushing with NULL input at the end in order to
1193  * give the complete and correct output.
1194  *
1195  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
1196  * with NULL data. The user can still send NULL data to the public encode
1197  * or decode function, but libavcodec will not pass it along to the codec
1198  * unless this flag is set.
1199  *
1200  * Decoders:
1201  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
1202  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
1203  * returns frames.
1204  *
1205  * Encoders:
1206  * The encoder needs to be fed with NULL data at the end of encoding until the
1207  * encoder no longer returns data.
1208  *
1209  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1210  * flag also means that the encoder must set the pts and duration for
1211  * each output packet. If this flag is not set, the pts and duration will
1212  * be determined by libavcodec from the input frame.
1213  */
1214 #define CODEC_CAP_DELAY AV_CODEC_CAP_DELAY
1215 /**
1216  * Codec can be fed a final frame with a smaller size.
1217  * This can be used to prevent truncation of the last audio samples.
1218  */
1219 #define CODEC_CAP_SMALL_LAST_FRAME AV_CODEC_CAP_SMALL_LAST_FRAME
1220 #if FF_API_CAP_VDPAU
1221 /**
1222  * Codec can export data for HW decoding (VDPAU).
1223  */
1224 #define CODEC_CAP_HWACCEL_VDPAU AV_CODEC_CAP_HWACCEL_VDPAU
1225 #endif
1226 /**
1227  * Codec can output multiple frames per AVPacket
1228  * Normally demuxers return one frame at a time, demuxers which do not do
1229  * are connected to a parser to split what they return into proper frames.
1230  * This flag is reserved to the very rare category of codecs which have a
1231  * bitstream that cannot be split into frames without timeconsuming
1232  * operations like full decoding. Demuxers carrying such bitstreams thus
1233  * may return multiple frames in a packet. This has many disadvantages like
1234  * prohibiting stream copy in many cases thus it should only be considered
1235  * as a last resort.
1236  */
1237 #define CODEC_CAP_SUBFRAMES AV_CODEC_CAP_SUBFRAMES
1238 /**
1239  * Codec is experimental and is thus avoided in favor of non experimental
1240  * encoders
1241  */
1242 #define CODEC_CAP_EXPERIMENTAL AV_CODEC_CAP_EXPERIMENTAL
1243 /**
1244  * Codec should fill in channel configuration and samplerate instead of container
1245  */
1246 #define CODEC_CAP_CHANNEL_CONF AV_CODEC_CAP_CHANNEL_CONF
1247 #if FF_API_NEG_LINESIZES
1248 /**
1249  * @deprecated no codecs use this capability
1250  */
1251 #define CODEC_CAP_NEG_LINESIZES 0x0800
1252 #endif
1253 /**
1254  * Codec supports frame-level multithreading.
1255  */
1256 #define CODEC_CAP_FRAME_THREADS AV_CODEC_CAP_FRAME_THREADS
1257 /**
1258  * Codec supports slice-based (or partition-based) multithreading.
1259  */
1260 #define CODEC_CAP_SLICE_THREADS AV_CODEC_CAP_SLICE_THREADS
1261 /**
1262  * Codec supports changed parameters at any point.
1263  */
1264 #define CODEC_CAP_PARAM_CHANGE AV_CODEC_CAP_PARAM_CHANGE
1265 /**
1266  * Codec supports avctx->thread_count == 0 (auto).
1267  */
1268 #define CODEC_CAP_AUTO_THREADS AV_CODEC_CAP_AUTO_THREADS
1269 /**
1270  * Audio encoder supports receiving a different number of samples in each call.
1271  */
1272 #define CODEC_CAP_VARIABLE_FRAME_SIZE AV_CODEC_CAP_VARIABLE_FRAME_SIZE
1273 /**
1274  * Codec is intra only.
1275  */
1276 #define CODEC_CAP_INTRA_ONLY AV_CODEC_CAP_INTRA_ONLY
1277 /**
1278  * Codec is lossless.
1279  */
1280 #define CODEC_CAP_LOSSLESS AV_CODEC_CAP_LOSSLESS
1281 
1282 /**
1283  * HWAccel is experimental and is thus avoided in favor of non experimental
1284  * codecs
1285  */
1286 #define HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
1287 #endif /* FF_API_WITHOUT_PREFIX */
1288 
1289 #if FF_API_MB_TYPE
1290 //The following defines may change, don't expect compatibility if you use them.
1291 #define MB_TYPE_INTRA4x4 0x0001
1292 #define MB_TYPE_INTRA16x16 0x0002 //FIXME H.264-specific
1293 #define MB_TYPE_INTRA_PCM 0x0004 //FIXME H.264-specific
1294 #define MB_TYPE_16x16 0x0008
1295 #define MB_TYPE_16x8 0x0010
1296 #define MB_TYPE_8x16 0x0020
1297 #define MB_TYPE_8x8 0x0040
1298 #define MB_TYPE_INTERLACED 0x0080
1299 #define MB_TYPE_DIRECT2 0x0100 //FIXME
1300 #define MB_TYPE_ACPRED 0x0200
1301 #define MB_TYPE_GMC 0x0400
1302 #define MB_TYPE_SKIP 0x0800
1303 #define MB_TYPE_P0L0 0x1000
1304 #define MB_TYPE_P1L0 0x2000
1305 #define MB_TYPE_P0L1 0x4000
1306 #define MB_TYPE_P1L1 0x8000
1307 #define MB_TYPE_L0 (MB_TYPE_P0L0 | MB_TYPE_P1L0)
1308 #define MB_TYPE_L1 (MB_TYPE_P0L1 | MB_TYPE_P1L1)
1309 #define MB_TYPE_L0L1 (MB_TYPE_L0 | MB_TYPE_L1)
1310 #define MB_TYPE_QUANT 0x00010000
1311 #define MB_TYPE_CBP 0x00020000
1312 // Note bits 24-31 are reserved for codec specific use (H.264 ref0, MPEG-1 0mv, ...)
1313 #endif
1314 
1315 /**
1316  * Pan Scan area.
1317  * This specifies the area which should be displayed.
1318  * Note there may be multiple such areas for one frame.
1319  */
1320 typedef struct AVPanScan{
1321  /**
1322  * id
1323  * - encoding: Set by user.
1324  * - decoding: Set by libavcodec.
1325  */
1326  int id;
1327 
1328  /**
1329  * width and height in 1/16 pel
1330  * - encoding: Set by user.
1331  * - decoding: Set by libavcodec.
1332  */
1333  int width;
1334  int height;
1335 
1336  /**
1337  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1338  * - encoding: Set by user.
1339  * - decoding: Set by libavcodec.
1340  */
1341  int16_t position[3][2];
1342 }AVPanScan;
1343 
1344 /**
1345  * This structure describes the bitrate properties of an encoded bitstream. It
1346  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1347  * parameters for H.264/HEVC.
1348  */
1349 typedef struct AVCPBProperties {
1350  /**
1351  * Maximum bitrate of the stream, in bits per second.
1352  * Zero if unknown or unspecified.
1353  */
1355  /**
1356  * Minimum bitrate of the stream, in bits per second.
1357  * Zero if unknown or unspecified.
1358  */
1360  /**
1361  * Average bitrate of the stream, in bits per second.
1362  * Zero if unknown or unspecified.
1363  */
1365 
1366  /**
1367  * The size of the buffer to which the ratecontrol is applied, in bits.
1368  * Zero if unknown or unspecified.
1369  */
1371 
1372  /**
1373  * The delay between the time the packet this structure is associated with
1374  * is received and the time when it should be decoded, in periods of a 27MHz
1375  * clock.
1376  *
1377  * UINT64_MAX when unknown or unspecified.
1378  */
1379  uint64_t vbv_delay;
1380 } AVCPBProperties;
1381 
1382 #if FF_API_QSCALE_TYPE
1383 #define FF_QSCALE_TYPE_MPEG1 0
1384 #define FF_QSCALE_TYPE_MPEG2 1
1385 #define FF_QSCALE_TYPE_H264 2
1386 #define FF_QSCALE_TYPE_VP56 3
1387 #endif
1388 
1389 /**
1390  * The decoder will keep a reference to the frame and may reuse it later.
1391  */
1392 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1393 
1394 /**
1395  * @defgroup lavc_packet AVPacket
1396  *
1397  * Types and functions for working with AVPacket.
1398  * @{
1399  */
1401  /**
1402  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1403  * bytes worth of palette. This side data signals that a new palette is
1404  * present.
1405  */
1407 
1408  /**
1409  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1410  * that the extradata buffer was changed and the receiving side should
1411  * act upon it appropriately. The new extradata is embedded in the side
1412  * data buffer and should be immediately used for processing the current
1413  * frame or packet.
1414  */
1416 
1417  /**
1418  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1419  * @code
1420  * u32le param_flags
1421  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1422  * s32le channel_count
1423  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1424  * u64le channel_layout
1425  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1426  * s32le sample_rate
1427  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1428  * s32le width
1429  * s32le height
1430  * @endcode
1431  */
1433 
1434  /**
1435  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1436  * structures with info about macroblocks relevant to splitting the
1437  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1438  * That is, it does not necessarily contain info about all macroblocks,
1439  * as long as the distance between macroblocks in the info is smaller
1440  * than the target payload size.
1441  * Each MB info structure is 12 bytes, and is laid out as follows:
1442  * @code
1443  * u32le bit offset from the start of the packet
1444  * u8 current quantizer at the start of the macroblock
1445  * u8 GOB number
1446  * u16le macroblock address within the GOB
1447  * u8 horizontal MV predictor
1448  * u8 vertical MV predictor
1449  * u8 horizontal MV predictor for block number 3
1450  * u8 vertical MV predictor for block number 3
1451  * @endcode
1452  */
1454 
1455  /**
1456  * This side data should be associated with an audio stream and contains
1457  * ReplayGain information in form of the AVReplayGain struct.
1458  */
1460 
1461  /**
1462  * This side data contains a 3x3 transformation matrix describing an affine
1463  * transformation that needs to be applied to the decoded video frames for
1464  * correct presentation.
1465  *
1466  * See libavutil/display.h for a detailed description of the data.
1467  */
1469 
1470  /**
1471  * This side data should be associated with a video stream and contains
1472  * Stereoscopic 3D information in form of the AVStereo3D struct.
1473  */
1475 
1476  /**
1477  * This side data should be associated with an audio stream and corresponds
1478  * to enum AVAudioServiceType.
1479  */
1481 
1482  /**
1483  * This side data contains quality related information from the encoder.
1484  * @code
1485  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1486  * u8 picture type
1487  * u8 error count
1488  * u16 reserved
1489  * u64le[error count] sum of squared differences between encoder in and output
1490  * @endcode
1491  */
1493 
1494  /**
1495  * This side data contains an integer value representing the stream index
1496  * of a "fallback" track. A fallback track indicates an alternate
1497  * track to use when the current track can not be decoded for some reason.
1498  * e.g. no decoder available for codec.
1499  */
1501 
1502  /**
1503  * This side data corresponds to the AVCPBProperties struct.
1504  */
1506 
1507  /**
1508  * Recommmends skipping the specified number of samples
1509  * @code
1510  * u32le number of samples to skip from start of this packet
1511  * u32le number of samples to skip from end of this packet
1512  * u8 reason for start skip
1513  * u8 reason for end skip (0=padding silence, 1=convergence)
1514  * @endcode
1515  */
1517 
1518  /**
1519  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1520  * the packet may contain "dual mono" audio specific to Japanese DTV
1521  * and if it is true, recommends only the selected channel to be used.
1522  * @code
1523  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1524  * @endcode
1525  */
1527 
1528  /**
1529  * A list of zero terminated key/value strings. There is no end marker for
1530  * the list, so it is required to rely on the side data size to stop.
1531  */
1533 
1534  /**
1535  * Subtitle event position
1536  * @code
1537  * u32le x1
1538  * u32le y1
1539  * u32le x2
1540  * u32le y2
1541  * @endcode
1542  */
1544 
1545  /**
1546  * Data found in BlockAdditional element of matroska container. There is
1547  * no end marker for the data, so it is required to rely on the side data
1548  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1549  * by data.
1550  */
1552 
1553  /**
1554  * The optional first identifier line of a WebVTT cue.
1555  */
1557 
1558  /**
1559  * The optional settings (rendering instructions) that immediately
1560  * follow the timestamp specifier of a WebVTT cue.
1561  */
1563 
1564  /**
1565  * A list of zero terminated key/value strings. There is no end marker for
1566  * the list, so it is required to rely on the side data size to stop. This
1567  * side data includes updated metadata which appeared in the stream.
1568  */
1570 
1571  /**
1572  * MPEGTS stream ID, this is required to pass the stream ID
1573  * information from the demuxer to the corresponding muxer.
1574  */
1576 
1577  /**
1578  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1579  * should be associated with a video stream and contains data in the form
1580  * of the AVMasteringDisplayMetadata struct.
1581  */
1583 
1584  /**
1585  * This side data should be associated with a video stream and corresponds
1586  * to the AVSphericalMapping structure.
1587  */
1589 
1590  /**
1591  * Content light level (based on CTA-861.3). This metadata should be
1592  * associated with a video stream and contains data in the form of the
1593  * AVContentLightMetadata struct.
1594  */
1596 };
1597 
1598 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1599 
1600 typedef struct AVPacketSideData {
1602  int size;
1605 
1606 /**
1607  * This structure stores compressed data. It is typically exported by demuxers
1608  * and then passed as input to decoders, or received as output from encoders and
1609  * then passed to muxers.
1610  *
1611  * For video, it should typically contain one compressed frame. For audio it may
1612  * contain several compressed frames. Encoders are allowed to output empty
1613  * packets, with no compressed data, containing only side data
1614  * (e.g. to update some stream parameters at the end of encoding).
1615  *
1616  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1617  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1618  * without libavcodec and libavformat major bump.
1619  *
1620  * The semantics of data ownership depends on the buf field.
1621  * If it is set, the packet data is dynamically allocated and is
1622  * valid indefinitely until a call to av_packet_unref() reduces the
1623  * reference count to 0.
1624  *
1625  * If the buf field is not set av_packet_ref() would make a copy instead
1626  * of increasing the reference count.
1627  *
1628  * The side data is always allocated with av_malloc(), copied by
1629  * av_packet_ref() and freed by av_packet_unref().
1630  *
1631  * @see av_packet_ref
1632  * @see av_packet_unref
1633  */
1634 typedef struct AVPacket {
1635  /**
1636  * A reference to the reference-counted buffer where the packet data is
1637  * stored.
1638  * May be NULL, then the packet data is not reference-counted.
1639  */
1641  /**
1642  * Presentation timestamp in AVStream->time_base units; the time at which
1643  * the decompressed packet will be presented to the user.
1644  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1645  * pts MUST be larger or equal to dts as presentation cannot happen before
1646  * decompression, unless one wants to view hex dumps. Some formats misuse
1647  * the terms dts and pts/cts to mean something different. Such timestamps
1648  * must be converted to true pts/dts before they are stored in AVPacket.
1649  */
1650  int64_t pts;
1651  /**
1652  * Decompression timestamp in AVStream->time_base units; the time at which
1653  * the packet is decompressed.
1654  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1655  */
1656  int64_t dts;
1658  int size;
1660  /**
1661  * A combination of AV_PKT_FLAG values
1662  */
1663  int flags;
1664  /**
1665  * Additional packet data that can be provided by the container.
1666  * Packet can contain several types of side information.
1667  */
1670 
1671  /**
1672  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1673  * Equals next_pts - this_pts in presentation order.
1674  */
1675  int64_t duration;
1676 
1677  int64_t pos; ///< byte position in stream, -1 if unknown
1678 
1679 #if FF_API_CONVERGENCE_DURATION
1680  /**
1681  * @deprecated Same as the duration field, but as int64_t. This was required
1682  * for Matroska subtitles, whose duration values could overflow when the
1683  * duration field was still an int.
1684  */
1687 #endif
1688 } AVPacket;
1689 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1690 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1691 /**
1692  * Flag is used to discard packets which are required to maintain valid
1693  * decoder state but are not required for output and should be dropped
1694  * after decoding.
1695  **/
1696 #define AV_PKT_FLAG_DISCARD 0x0004
1697 
1703 };
1704 /**
1705  * @}
1706  */
1707 
1708 struct AVCodecInternal;
1709 
1713  AV_FIELD_TT, //< Top coded_first, top displayed first
1714  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1715  AV_FIELD_TB, //< Top coded first, bottom displayed first
1716  AV_FIELD_BT, //< Bottom coded first, top displayed first
1717 };
1718 
1719 /**
1720  * main external API structure.
1721  * New fields can be added to the end with minor version bumps.
1722  * Removal, reordering and changes to existing fields require a major
1723  * version bump.
1724  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1725  * applications.
1726  * The name string for AVOptions options matches the associated command line
1727  * parameter name and can be found in libavcodec/options_table.h
1728  * The AVOption/command line parameter names differ in some cases from the C
1729  * structure field names for historic reasons or brevity.
1730  * sizeof(AVCodecContext) must not be used outside libav*.
1731  */
1732 typedef struct AVCodecContext {
1733  /**
1734  * information on struct for av_log
1735  * - set by avcodec_alloc_context3
1736  */
1739 
1740  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1741  const struct AVCodec *codec;
1742 #if FF_API_CODEC_NAME
1743  /**
1744  * @deprecated this field is not used for anything in libavcodec
1745  */
1747  char codec_name[32];
1748 #endif
1749  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1750 
1751  /**
1752  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1753  * This is used to work around some encoder bugs.
1754  * A demuxer should set this to what is stored in the field used to identify the codec.
1755  * If there are multiple such fields in a container then the demuxer should choose the one
1756  * which maximizes the information about the used codec.
1757  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1758  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1759  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1760  * first.
1761  * - encoding: Set by user, if not then the default based on codec_id will be used.
1762  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1763  */
1764  unsigned int codec_tag;
1765 
1766 #if FF_API_STREAM_CODEC_TAG
1767  /**
1768  * @deprecated this field is unused
1769  */
1771  unsigned int stream_codec_tag;
1772 #endif
1773 
1774  void *priv_data;
1775 
1776  /**
1777  * Private context used for internal data.
1778  *
1779  * Unlike priv_data, this is not codec-specific. It is used in general
1780  * libavcodec functions.
1781  */
1782  struct AVCodecInternal *internal;
1783 
1784  /**
1785  * Private data of the user, can be used to carry app specific stuff.
1786  * - encoding: Set by user.
1787  * - decoding: Set by user.
1788  */
1789  void *opaque;
1790 
1791  /**
1792  * the average bitrate
1793  * - encoding: Set by user; unused for constant quantizer encoding.
1794  * - decoding: Set by user, may be overwritten by libavcodec
1795  * if this info is available in the stream
1796  */
1797  int64_t bit_rate;
1798 
1799  /**
1800  * number of bits the bitstream is allowed to diverge from the reference.
1801  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1802  * - encoding: Set by user; unused for constant quantizer encoding.
1803  * - decoding: unused
1804  */
1806 
1807  /**
1808  * Global quality for codecs which cannot change it per frame.
1809  * This should be proportional to MPEG-1/2/4 qscale.
1810  * - encoding: Set by user.
1811  * - decoding: unused
1812  */
1814 
1815  /**
1816  * - encoding: Set by user.
1817  * - decoding: unused
1818  */
1820 #define FF_COMPRESSION_DEFAULT -1
1821 
1822  /**
1823  * AV_CODEC_FLAG_*.
1824  * - encoding: Set by user.
1825  * - decoding: Set by user.
1826  */
1827  int flags;
1828 
1829  /**
1830  * AV_CODEC_FLAG2_*
1831  * - encoding: Set by user.
1832  * - decoding: Set by user.
1833  */
1834  int flags2;
1835 
1836  /**
1837  * some codecs need / can use extradata like Huffman tables.
1838  * MJPEG: Huffman tables
1839  * rv10: additional flags
1840  * MPEG-4: global headers (they can be in the bitstream or here)
1841  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1842  * than extradata_size to avoid problems if it is read with the bitstream reader.
1843  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1844  * - encoding: Set/allocated/freed by libavcodec.
1845  * - decoding: Set/allocated/freed by user.
1846  */
1849 
1850  /**
1851  * This is the fundamental unit of time (in seconds) in terms
1852  * of which frame timestamps are represented. For fixed-fps content,
1853  * timebase should be 1/framerate and timestamp increments should be
1854  * identically 1.
1855  * This often, but not always is the inverse of the frame rate or field rate
1856  * for video. 1/time_base is not the average frame rate if the frame rate is not
1857  * constant.
1858  *
1859  * Like containers, elementary streams also can store timestamps, 1/time_base
1860  * is the unit in which these timestamps are specified.
1861  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1862  * vop_time_increment_resolution and fixed_vop_rate
1863  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1864  *
1865  * - encoding: MUST be set by user.
1866  * - decoding: the use of this field for decoding is deprecated.
1867  * Use framerate instead.
1868  */
1870 
1871  /**
1872  * For some codecs, the time base is closer to the field rate than the frame rate.
1873  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1874  * if no telecine is used ...
1875  *
1876  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1877  */
1879 
1880  /**
1881  * Codec delay.
1882  *
1883  * Encoding: Number of frames delay there will be from the encoder input to
1884  * the decoder output. (we assume the decoder matches the spec)
1885  * Decoding: Number of frames delay in addition to what a standard decoder
1886  * as specified in the spec would produce.
1887  *
1888  * Video:
1889  * Number of frames the decoded output will be delayed relative to the
1890  * encoded input.
1891  *
1892  * Audio:
1893  * For encoding, this field is unused (see initial_padding).
1894  *
1895  * For decoding, this is the number of samples the decoder needs to
1896  * output before the decoder's output is valid. When seeking, you should
1897  * start decoding this many samples prior to your desired seek point.
1898  *
1899  * - encoding: Set by libavcodec.
1900  * - decoding: Set by libavcodec.
1901  */
1902  int delay;
1903 
1904 
1905  /* video only */
1906  /**
1907  * picture width / height.
1908  *
1909  * @note Those fields may not match the values of the last
1910  * AVFrame output by avcodec_decode_video2 due frame
1911  * reordering.
1912  *
1913  * - encoding: MUST be set by user.
1914  * - decoding: May be set by the user before opening the decoder if known e.g.
1915  * from the container. Some decoders will require the dimensions
1916  * to be set by the caller. During decoding, the decoder may
1917  * overwrite those values as required while parsing the data.
1918  */
1920 
1921  /**
1922  * Bitstream width / height, may be different from width/height e.g. when
1923  * the decoded frame is cropped before being output or lowres is enabled.
1924  *
1925  * @note Those field may not match the value of the last
1926  * AVFrame output by avcodec_receive_frame() due frame
1927  * reordering.
1928  *
1929  * - encoding: unused
1930  * - decoding: May be set by the user before opening the decoder if known
1931  * e.g. from the container. During decoding, the decoder may
1932  * overwrite those values as required while parsing the data.
1933  */
1935 
1936 #if FF_API_ASPECT_EXTENDED
1937 #define FF_ASPECT_EXTENDED 15
1938 #endif
1939 
1940  /**
1941  * the number of pictures in a group of pictures, or 0 for intra_only
1942  * - encoding: Set by user.
1943  * - decoding: unused
1944  */
1946 
1947  /**
1948  * Pixel format, see AV_PIX_FMT_xxx.
1949  * May be set by the demuxer if known from headers.
1950  * May be overridden by the decoder if it knows better.
1951  *
1952  * @note This field may not match the value of the last
1953  * AVFrame output by avcodec_receive_frame() due frame
1954  * reordering.
1955  *
1956  * - encoding: Set by user.
1957  * - decoding: Set by user if known, overridden by libavcodec while
1958  * parsing the data.
1959  */
1961 
1962 #if FF_API_MOTION_EST
1963  /**
1964  * This option does nothing
1965  * @deprecated use codec private options instead
1966  */
1968 #endif
1969 
1970  /**
1971  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1972  * decoder to draw a horizontal band. It improves cache usage. Not
1973  * all codecs can do that. You must check the codec capabilities
1974  * beforehand.
1975  * When multithreading is used, it may be called from multiple threads
1976  * at the same time; threads might draw different parts of the same AVFrame,
1977  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1978  * in order.
1979  * The function is also used by hardware acceleration APIs.
1980  * It is called at least once during frame decoding to pass
1981  * the data needed for hardware render.
1982  * In that mode instead of pixel data, AVFrame points to
1983  * a structure specific to the acceleration API. The application
1984  * reads the structure and can change some fields to indicate progress
1985  * or mark state.
1986  * - encoding: unused
1987  * - decoding: Set by user.
1988  * @param height the height of the slice
1989  * @param y the y position of the slice
1990  * @param type 1->top field, 2->bottom field, 3->frame
1991  * @param offset offset into the AVFrame.data from which the slice should be read
1992  */
1994  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1995  int y, int type, int height);
1996 
1997  /**
1998  * callback to negotiate the pixelFormat
1999  * @param fmt is the list of formats which are supported by the codec,
2000  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
2001  * The first is always the native one.
2002  * @note The callback may be called again immediately if initialization for
2003  * the selected (hardware-accelerated) pixel format failed.
2004  * @warning Behavior is undefined if the callback returns a value not
2005  * in the fmt list of formats.
2006  * @return the chosen format
2007  * - encoding: unused
2008  * - decoding: Set by user, if not set the native format will be chosen.
2009  */
2010  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
2011 
2012  /**
2013  * maximum number of B-frames between non-B-frames
2014  * Note: The output will be delayed by max_b_frames+1 relative to the input.
2015  * - encoding: Set by user.
2016  * - decoding: unused
2017  */
2019 
2020  /**
2021  * qscale factor between IP and B-frames
2022  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
2023  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
2024  * - encoding: Set by user.
2025  * - decoding: unused
2026  */
2028 
2029 #if FF_API_RC_STRATEGY
2030  /** @deprecated use codec private option instead */
2032 #define FF_RC_STRATEGY_XVID 1
2033 #endif
2034 
2035 #if FF_API_PRIVATE_OPT
2036  /** @deprecated use encoder private options instead */
2039 #endif
2040 
2041  /**
2042  * qscale offset between IP and B-frames
2043  * - encoding: Set by user.
2044  * - decoding: unused
2045  */
2047 
2048  /**
2049  * Size of the frame reordering buffer in the decoder.
2050  * For MPEG-2 it is 1 IPB or 0 low delay IP.
2051  * - encoding: Set by libavcodec.
2052  * - decoding: Set by libavcodec.
2053  */
2055 
2056 #if FF_API_PRIVATE_OPT
2057  /** @deprecated use encoder private options instead */
2060 #endif
2061 
2062  /**
2063  * qscale factor between P- and I-frames
2064  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
2065  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
2066  * - encoding: Set by user.
2067  * - decoding: unused
2068  */
2070 
2071  /**
2072  * qscale offset between P and I-frames
2073  * - encoding: Set by user.
2074  * - decoding: unused
2075  */
2077 
2078  /**
2079  * luminance masking (0-> disabled)
2080  * - encoding: Set by user.
2081  * - decoding: unused
2082  */
2084 
2085  /**
2086  * temporary complexity masking (0-> disabled)
2087  * - encoding: Set by user.
2088  * - decoding: unused
2089  */
2091 
2092  /**
2093  * spatial complexity masking (0-> disabled)
2094  * - encoding: Set by user.
2095  * - decoding: unused
2096  */
2098 
2099  /**
2100  * p block masking (0-> disabled)
2101  * - encoding: Set by user.
2102  * - decoding: unused
2103  */
2104  float p_masking;
2105 
2106  /**
2107  * darkness masking (0-> disabled)
2108  * - encoding: Set by user.
2109  * - decoding: unused
2110  */
2112 
2113  /**
2114  * slice count
2115  * - encoding: Set by libavcodec.
2116  * - decoding: Set by user (or 0).
2117  */
2119 
2120 #if FF_API_PRIVATE_OPT
2121  /** @deprecated use encoder private options instead */
2124 #define FF_PRED_LEFT 0
2125 #define FF_PRED_PLANE 1
2126 #define FF_PRED_MEDIAN 2
2127 #endif
2128 
2129  /**
2130  * slice offsets in the frame in bytes
2131  * - encoding: Set/allocated by libavcodec.
2132  * - decoding: Set/allocated by user (or NULL).
2133  */
2135 
2136  /**
2137  * sample aspect ratio (0 if unknown)
2138  * That is the width of a pixel divided by the height of the pixel.
2139  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
2140  * - encoding: Set by user.
2141  * - decoding: Set by libavcodec.
2142  */
2144 
2145  /**
2146  * motion estimation comparison function
2147  * - encoding: Set by user.
2148  * - decoding: unused
2149  */
2150  int me_cmp;
2151  /**
2152  * subpixel motion estimation comparison function
2153  * - encoding: Set by user.
2154  * - decoding: unused
2155  */
2157  /**
2158  * macroblock comparison function (not supported yet)
2159  * - encoding: Set by user.
2160  * - decoding: unused
2161  */
2162  int mb_cmp;
2163  /**
2164  * interlaced DCT comparison function
2165  * - encoding: Set by user.
2166  * - decoding: unused
2167  */
2169 #define FF_CMP_SAD 0
2170 #define FF_CMP_SSE 1
2171 #define FF_CMP_SATD 2
2172 #define FF_CMP_DCT 3
2173 #define FF_CMP_PSNR 4
2174 #define FF_CMP_BIT 5
2175 #define FF_CMP_RD 6
2176 #define FF_CMP_ZERO 7
2177 #define FF_CMP_VSAD 8
2178 #define FF_CMP_VSSE 9
2179 #define FF_CMP_NSSE 10
2180 #define FF_CMP_W53 11
2181 #define FF_CMP_W97 12
2182 #define FF_CMP_DCTMAX 13
2183 #define FF_CMP_DCT264 14
2184 #define FF_CMP_MEDIAN_SAD 15
2185 #define FF_CMP_CHROMA 256
2186 
2187  /**
2188  * ME diamond size & shape
2189  * - encoding: Set by user.
2190  * - decoding: unused
2191  */
2193 
2194  /**
2195  * amount of previous MV predictors (2a+1 x 2a+1 square)
2196  * - encoding: Set by user.
2197  * - decoding: unused
2198  */
2200 
2201 #if FF_API_PRIVATE_OPT
2202  /** @deprecated use encoder private options instead */
2204  int pre_me;
2205 #endif
2206 
2207  /**
2208  * motion estimation prepass comparison function
2209  * - encoding: Set by user.
2210  * - decoding: unused
2211  */
2213 
2214  /**
2215  * ME prepass diamond size & shape
2216  * - encoding: Set by user.
2217  * - decoding: unused
2218  */
2220 
2221  /**
2222  * subpel ME quality
2223  * - encoding: Set by user.
2224  * - decoding: unused
2225  */
2227 
2228 #if FF_API_AFD
2229  /**
2230  * DTG active format information (additional aspect ratio
2231  * information only used in DVB MPEG-2 transport streams)
2232  * 0 if not set.
2233  *
2234  * - encoding: unused
2235  * - decoding: Set by decoder.
2236  * @deprecated Deprecated in favor of AVSideData
2237  */
2239 #define FF_DTG_AFD_SAME 8
2240 #define FF_DTG_AFD_4_3 9
2241 #define FF_DTG_AFD_16_9 10
2242 #define FF_DTG_AFD_14_9 11
2243 #define FF_DTG_AFD_4_3_SP_14_9 13
2244 #define FF_DTG_AFD_16_9_SP_14_9 14
2245 #define FF_DTG_AFD_SP_4_3 15
2246 #endif /* FF_API_AFD */
2247 
2248  /**
2249  * maximum motion estimation search range in subpel units
2250  * If 0 then no limit.
2251  *
2252  * - encoding: Set by user.
2253  * - decoding: unused
2254  */
2256 
2257 #if FF_API_QUANT_BIAS
2258  /**
2259  * @deprecated use encoder private option instead
2260  */
2262 #define FF_DEFAULT_QUANT_BIAS 999999
2263 
2264  /**
2265  * @deprecated use encoder private option instead
2266  */
2268 #endif
2269 
2270  /**
2271  * slice flags
2272  * - encoding: unused
2273  * - decoding: Set by user.
2274  */
2276 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2277 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2278 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2279 
2280 #if FF_API_XVMC
2281  /**
2282  * XVideo Motion Acceleration
2283  * - encoding: forbidden
2284  * - decoding: set by decoder
2285  * @deprecated XvMC doesn't need it anymore.
2286  */
2287  attribute_deprecated int xvmc_acceleration;
2288 #endif /* FF_API_XVMC */
2289 
2290  /**
2291  * macroblock decision mode
2292  * - encoding: Set by user.
2293  * - decoding: unused
2294  */
2296 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2297 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2298 #define FF_MB_DECISION_RD 2 ///< rate distortion
2299 
2300  /**
2301  * custom intra quantization matrix
2302  * - encoding: Set by user, can be NULL.
2303  * - decoding: Set by libavcodec.
2304  */
2305  uint16_t *intra_matrix;
2306 
2307  /**
2308  * custom inter quantization matrix
2309  * - encoding: Set by user, can be NULL.
2310  * - decoding: Set by libavcodec.
2311  */
2312  uint16_t *inter_matrix;
2313 
2314 #if FF_API_PRIVATE_OPT
2315  /** @deprecated use encoder private options instead */
2318 
2319  /** @deprecated use encoder private options instead */
2322 #endif
2323 
2324 #if FF_API_MPV_OPT
2325  /**
2326  * @deprecated this field is unused
2327  */
2330 
2331  /**
2332  * @deprecated this field is unused
2333  */
2336 #endif
2337 
2338  /**
2339  * precision of the intra DC coefficient - 8
2340  * - encoding: Set by user.
2341  * - decoding: Set by libavcodec
2342  */
2344 
2345  /**
2346  * Number of macroblock rows at the top which are skipped.
2347  * - encoding: unused
2348  * - decoding: Set by user.
2349  */
2351 
2352  /**
2353  * Number of macroblock rows at the bottom which are skipped.
2354  * - encoding: unused
2355  * - decoding: Set by user.
2356  */
2358 
2359 #if FF_API_MPV_OPT
2360  /**
2361  * @deprecated use encoder private options instead
2362  */
2365 #endif
2366 
2367  /**
2368  * minimum MB Lagrange multiplier
2369  * - encoding: Set by user.
2370  * - decoding: unused
2371  */
2372  int mb_lmin;
2373 
2374  /**
2375  * maximum MB Lagrange multiplier
2376  * - encoding: Set by user.
2377  * - decoding: unused
2378  */
2379  int mb_lmax;
2380 
2381 #if FF_API_PRIVATE_OPT
2382  /**
2383  * @deprecated use encoder private options instead
2384  */
2387 #endif
2388 
2389  /**
2390  * - encoding: Set by user.
2391  * - decoding: unused
2392  */
2394 
2395 #if FF_API_PRIVATE_OPT
2396  /** @deprecated use encoder private options instead */
2399 #endif
2400 
2401  /**
2402  * minimum GOP size
2403  * - encoding: Set by user.
2404  * - decoding: unused
2405  */
2407 
2408  /**
2409  * number of reference frames
2410  * - encoding: Set by user.
2411  * - decoding: Set by lavc.
2412  */
2413  int refs;
2414 
2415 #if FF_API_PRIVATE_OPT
2416  /** @deprecated use encoder private options instead */
2419 #endif
2420 
2421 #if FF_API_UNUSED_MEMBERS
2422  /**
2423  * Multiplied by qscale for each frame and added to scene_change_score.
2424  * - encoding: Set by user.
2425  * - decoding: unused
2426  */
2428 #endif
2429 
2430  /**
2431  * Note: Value depends upon the compare function used for fullpel ME.
2432  * - encoding: Set by user.
2433  * - decoding: unused
2434  */
2436 
2437 #if FF_API_PRIVATE_OPT
2438  /** @deprecated use encoder private options instead */
2441 #endif
2442 
2443  /**
2444  * Chromaticity coordinates of the source primaries.
2445  * - encoding: Set by user
2446  * - decoding: Set by libavcodec
2447  */
2449 
2450  /**
2451  * Color Transfer Characteristic.
2452  * - encoding: Set by user
2453  * - decoding: Set by libavcodec
2454  */
2456 
2457  /**
2458  * YUV colorspace type.
2459  * - encoding: Set by user
2460  * - decoding: Set by libavcodec
2461  */
2463 
2464  /**
2465  * MPEG vs JPEG YUV range.
2466  * - encoding: Set by user
2467  * - decoding: Set by libavcodec
2468  */
2470 
2471  /**
2472  * This defines the location of chroma samples.
2473  * - encoding: Set by user
2474  * - decoding: Set by libavcodec
2475  */
2477 
2478  /**
2479  * Number of slices.
2480  * Indicates number of picture subdivisions. Used for parallelized
2481  * decoding.
2482  * - encoding: Set by user
2483  * - decoding: unused
2484  */
2485  int slices;
2486 
2487  /** Field order
2488  * - encoding: set by libavcodec
2489  * - decoding: Set by user.
2490  */
2492 
2493  /* audio only */
2494  int sample_rate; ///< samples per second
2495  int channels; ///< number of audio channels
2496 
2497  /**
2498  * audio sample format
2499  * - encoding: Set by user.
2500  * - decoding: Set by libavcodec.
2501  */
2502  enum AVSampleFormat sample_fmt; ///< sample format
2503 
2504  /* The following data should not be initialized. */
2505  /**
2506  * Number of samples per channel in an audio frame.
2507  *
2508  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2509  * except the last must contain exactly frame_size samples per channel.
2510  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2511  * frame size is not restricted.
2512  * - decoding: may be set by some decoders to indicate constant frame size
2513  */
2515 
2516  /**
2517  * Frame counter, set by libavcodec.
2518  *
2519  * - decoding: total number of frames returned from the decoder so far.
2520  * - encoding: total number of frames passed to the encoder so far.
2521  *
2522  * @note the counter is not incremented if encoding/decoding resulted in
2523  * an error.
2524  */
2526 
2527  /**
2528  * number of bytes per packet if constant and known or 0
2529  * Used by some WAV based audio codecs.
2530  */
2532 
2533  /**
2534  * Audio cutoff bandwidth (0 means "automatic")
2535  * - encoding: Set by user.
2536  * - decoding: unused
2537  */
2538  int cutoff;
2539 
2540  /**
2541  * Audio channel layout.
2542  * - encoding: set by user.
2543  * - decoding: set by user, may be overwritten by libavcodec.
2544  */
2545  uint64_t channel_layout;
2546 
2547  /**
2548  * Request decoder to use this channel layout if it can (0 for default)
2549  * - encoding: unused
2550  * - decoding: Set by user.
2551  */
2553 
2554  /**
2555  * Type of service that the audio stream conveys.
2556  * - encoding: Set by user.
2557  * - decoding: Set by libavcodec.
2558  */
2560 
2561  /**
2562  * desired sample format
2563  * - encoding: Not used.
2564  * - decoding: Set by user.
2565  * Decoder will decode to this format if it can.
2566  */
2568 
2569  /**
2570  * This callback is called at the beginning of each frame to get data
2571  * buffer(s) for it. There may be one contiguous buffer for all the data or
2572  * there may be a buffer per each data plane or anything in between. What
2573  * this means is, you may set however many entries in buf[] you feel necessary.
2574  * Each buffer must be reference-counted using the AVBuffer API (see description
2575  * of buf[] below).
2576  *
2577  * The following fields will be set in the frame before this callback is
2578  * called:
2579  * - format
2580  * - width, height (video only)
2581  * - sample_rate, channel_layout, nb_samples (audio only)
2582  * Their values may differ from the corresponding values in
2583  * AVCodecContext. This callback must use the frame values, not the codec
2584  * context values, to calculate the required buffer size.
2585  *
2586  * This callback must fill the following fields in the frame:
2587  * - data[]
2588  * - linesize[]
2589  * - extended_data:
2590  * * if the data is planar audio with more than 8 channels, then this
2591  * callback must allocate and fill extended_data to contain all pointers
2592  * to all data planes. data[] must hold as many pointers as it can.
2593  * extended_data must be allocated with av_malloc() and will be freed in
2594  * av_frame_unref().
2595  * * otherwise extended_data must point to data
2596  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2597  * the frame's data and extended_data pointers must be contained in these. That
2598  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2599  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2600  * and av_buffer_ref().
2601  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2602  * this callback and filled with the extra buffers if there are more
2603  * buffers than buf[] can hold. extended_buf will be freed in
2604  * av_frame_unref().
2605  *
2606  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2607  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2608  * some other means.
2609  *
2610  * Each data plane must be aligned to the maximum required by the target
2611  * CPU.
2612  *
2613  * @see avcodec_default_get_buffer2()
2614  *
2615  * Video:
2616  *
2617  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2618  * (read and/or written to if it is writable) later by libavcodec.
2619  *
2620  * avcodec_align_dimensions2() should be used to find the required width and
2621  * height, as they normally need to be rounded up to the next multiple of 16.
2622  *
2623  * Some decoders do not support linesizes changing between frames.
2624  *
2625  * If frame multithreading is used and thread_safe_callbacks is set,
2626  * this callback may be called from a different thread, but not from more
2627  * than one at once. Does not need to be reentrant.
2628  *
2629  * @see avcodec_align_dimensions2()
2630  *
2631  * Audio:
2632  *
2633  * Decoders request a buffer of a particular size by setting
2634  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2635  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2636  * to a smaller value in the output frame.
2637  *
2638  * As a convenience, av_samples_get_buffer_size() and
2639  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2640  * functions to find the required data size and to fill data pointers and
2641  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2642  * since all planes must be the same size.
2643  *
2644  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2645  *
2646  * - encoding: unused
2647  * - decoding: Set by libavcodec, user can override.
2648  */
2650 
2651  /**
2652  * If non-zero, the decoded audio and video frames returned from
2653  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2654  * and are valid indefinitely. The caller must free them with
2655  * av_frame_unref() when they are not needed anymore.
2656  * Otherwise, the decoded frames must not be freed by the caller and are
2657  * only valid until the next decode call.
2658  *
2659  * This is always automatically enabled if avcodec_receive_frame() is used.
2660  *
2661  * - encoding: unused
2662  * - decoding: set by the caller before avcodec_open2().
2663  */
2665 
2666  /* - encoding parameters */
2667  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2668  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2669 
2670  /**
2671  * minimum quantizer
2672  * - encoding: Set by user.
2673  * - decoding: unused
2674  */
2675  int qmin;
2676 
2677  /**
2678  * maximum quantizer
2679  * - encoding: Set by user.
2680  * - decoding: unused
2681  */
2682  int qmax;
2683 
2684  /**
2685  * maximum quantizer difference between frames
2686  * - encoding: Set by user.
2687  * - decoding: unused
2688  */
2690 
2691 #if FF_API_MPV_OPT
2692  /**
2693  * @deprecated use encoder private options instead
2694  */
2696  float rc_qsquish;
2697 
2702 #endif
2703 
2704  /**
2705  * decoder bitstream buffer size
2706  * - encoding: Set by user.
2707  * - decoding: unused
2708  */
2710 
2711  /**
2712  * ratecontrol override, see RcOverride
2713  * - encoding: Allocated/set/freed by user.
2714  * - decoding: unused
2715  */
2718 
2719 #if FF_API_MPV_OPT
2720  /**
2721  * @deprecated use encoder private options instead
2722  */
2724  const char *rc_eq;
2725 #endif
2726 
2727  /**
2728  * maximum bitrate
2729  * - encoding: Set by user.
2730  * - decoding: Set by user, may be overwritten by libavcodec.
2731  */
2732  int64_t rc_max_rate;
2733 
2734  /**
2735  * minimum bitrate
2736  * - encoding: Set by user.
2737  * - decoding: unused
2738  */
2739  int64_t rc_min_rate;
2740 
2741 #if FF_API_MPV_OPT
2742  /**
2743  * @deprecated use encoder private options instead
2744  */
2747 
2750 #endif
2751 
2752  /**
2753  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2754  * - encoding: Set by user.
2755  * - decoding: unused.
2756  */
2758 
2759  /**
2760  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2761  * - encoding: Set by user.
2762  * - decoding: unused.
2763  */
2765 
2766  /**
2767  * Number of bits which should be loaded into the rc buffer before decoding starts.
2768  * - encoding: Set by user.
2769  * - decoding: unused
2770  */
2772 
2773 #if FF_API_CODER_TYPE
2774 #define FF_CODER_TYPE_VLC 0
2775 #define FF_CODER_TYPE_AC 1
2776 #define FF_CODER_TYPE_RAW 2
2777 #define FF_CODER_TYPE_RLE 3
2778 #if FF_API_UNUSED_MEMBERS
2779 #define FF_CODER_TYPE_DEFLATE 4
2780 #endif /* FF_API_UNUSED_MEMBERS */
2781  /**
2782  * @deprecated use encoder private options instead
2783  */
2786 #endif /* FF_API_CODER_TYPE */
2787 
2788 #if FF_API_PRIVATE_OPT
2789  /** @deprecated use encoder private options instead */
2792 #endif
2793 
2794 #if FF_API_MPV_OPT
2795  /**
2796  * @deprecated use encoder private options instead
2797  */
2799  int lmin;
2800 
2801  /**
2802  * @deprecated use encoder private options instead
2803  */
2805  int lmax;
2806 #endif
2807 
2808 #if FF_API_PRIVATE_OPT
2809  /** @deprecated use encoder private options instead */
2812 
2813  /** @deprecated use encoder private options instead */
2816 
2817  /** @deprecated use encoder private options instead */
2820 
2821  /** @deprecated use encoder private options instead */
2824 #endif /* FF_API_PRIVATE_OPT */
2825 
2826  /**
2827  * trellis RD quantization
2828  * - encoding: Set by user.
2829  * - decoding: unused
2830  */
2831  int trellis;
2832 
2833 #if FF_API_PRIVATE_OPT
2834  /** @deprecated use encoder private options instead */
2837 
2838  /** @deprecated use encoder private options instead */
2841 
2842  /** @deprecated use encoder private options instead */
2845 #endif
2846 
2847 #if FF_API_RTP_CALLBACK
2848  /**
2849  * @deprecated unused
2850  */
2851  /* The RTP callback: This function is called */
2852  /* every time the encoder has a packet to send. */
2853  /* It depends on the encoder if the data starts */
2854  /* with a Start Code (it should). H.263 does. */
2855  /* mb_nb contains the number of macroblocks */
2856  /* encoded in the RTP payload. */
2858  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2859 #endif
2860 
2861 #if FF_API_PRIVATE_OPT
2862  /** @deprecated use encoder private options instead */
2864  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2865  /* do its best to deliver a chunk with size */
2866  /* below rtp_payload_size, the chunk will start */
2867  /* with a start code on some codecs like H.263. */
2868  /* This doesn't take account of any particular */
2869  /* headers inside the transmitted RTP payload. */
2870 #endif
2871 
2872 #if FF_API_STAT_BITS
2873  /* statistics, used for 2-pass encoding */
2875  int mv_bits;
2883  int i_count;
2885  int p_count;
2890 
2891  /** @deprecated this field is unused */
2894 #endif
2895 
2896  /**
2897  * pass1 encoding statistics output buffer
2898  * - encoding: Set by libavcodec.
2899  * - decoding: unused
2900  */
2901  char *stats_out;
2902 
2903  /**
2904  * pass2 encoding statistics input buffer
2905  * Concatenated stuff from stats_out of pass1 should be placed here.
2906  * - encoding: Allocated/set/freed by user.
2907  * - decoding: unused
2908  */
2909  char *stats_in;
2910 
2911  /**
2912  * Work around bugs in encoders which sometimes cannot be detected automatically.
2913  * - encoding: Set by user
2914  * - decoding: Set by user
2915  */
2917 #define FF_BUG_AUTODETECT 1 ///< autodetection
2918 #if FF_API_OLD_MSMPEG4
2919 #define FF_BUG_OLD_MSMPEG4 2
2920 #endif
2921 #define FF_BUG_XVID_ILACE 4
2922 #define FF_BUG_UMP4 8
2923 #define FF_BUG_NO_PADDING 16
2924 #define FF_BUG_AMV 32
2925 #if FF_API_AC_VLC
2926 #define FF_BUG_AC_VLC 0 ///< Will be removed, libavcodec can now handle these non-compliant files by default.
2927 #endif
2928 #define FF_BUG_QPEL_CHROMA 64
2929 #define FF_BUG_STD_QPEL 128
2930 #define FF_BUG_QPEL_CHROMA2 256
2931 #define FF_BUG_DIRECT_BLOCKSIZE 512
2932 #define FF_BUG_EDGE 1024
2933 #define FF_BUG_HPEL_CHROMA 2048
2934 #define FF_BUG_DC_CLIP 4096
2935 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2936 #define FF_BUG_TRUNCATED 16384
2937 #define FF_BUG_IEDGE 32768
2938 
2939  /**
2940  * strictly follow the standard (MPEG-4, ...).
2941  * - encoding: Set by user.
2942  * - decoding: Set by user.
2943  * Setting this to STRICT or higher means the encoder and decoder will
2944  * generally do stupid things, whereas setting it to unofficial or lower
2945  * will mean the encoder might produce output that is not supported by all
2946  * spec-compliant decoders. Decoders don't differentiate between normal,
2947  * unofficial and experimental (that is, they always try to decode things
2948  * when they can) unless they are explicitly asked to behave stupidly
2949  * (=strictly conform to the specs)
2950  */
2952 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2953 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2954 #define FF_COMPLIANCE_NORMAL 0
2955 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2956 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2957 
2958  /**
2959  * error concealment flags
2960  * - encoding: unused
2961  * - decoding: Set by user.
2962  */
2964 #define FF_EC_GUESS_MVS 1
2965 #define FF_EC_DEBLOCK 2
2966 #define FF_EC_FAVOR_INTER 256
2967 
2968  /**
2969  * debug
2970  * - encoding: Set by user.
2971  * - decoding: Set by user.
2972  */
2973  int debug;
2974 #define FF_DEBUG_PICT_INFO 1
2975 #define FF_DEBUG_RC 2
2976 #define FF_DEBUG_BITSTREAM 4
2977 #define FF_DEBUG_MB_TYPE 8
2978 #define FF_DEBUG_QP 16
2979 #if FF_API_DEBUG_MV
2980 /**
2981  * @deprecated this option does nothing
2982  */
2983 #define FF_DEBUG_MV 32
2984 #endif
2985 #define FF_DEBUG_DCT_COEFF 0x00000040
2986 #define FF_DEBUG_SKIP 0x00000080
2987 #define FF_DEBUG_STARTCODE 0x00000100
2988 #if FF_API_UNUSED_MEMBERS
2989 #define FF_DEBUG_PTS 0x00000200
2990 #endif /* FF_API_UNUSED_MEMBERS */
2991 #define FF_DEBUG_ER 0x00000400
2992 #define FF_DEBUG_MMCO 0x00000800
2993 #define FF_DEBUG_BUGS 0x00001000
2994 #if FF_API_DEBUG_MV
2995 #define FF_DEBUG_VIS_QP 0x00002000
2996 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2997 #endif
2998 #define FF_DEBUG_BUFFERS 0x00008000
2999 #define FF_DEBUG_THREADS 0x00010000
3000 #define FF_DEBUG_GREEN_MD 0x00800000
3001 #define FF_DEBUG_NOMC 0x01000000
3002 
3003 #if FF_API_DEBUG_MV
3004  /**
3005  * debug
3006  * - encoding: Set by user.
3007  * - decoding: Set by user.
3008  */
3010 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
3011 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
3012 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
3013 #endif
3014 
3015  /**
3016  * Error recognition; may misdetect some more or less valid parts as errors.
3017  * - encoding: unused
3018  * - decoding: Set by user.
3019  */
3021 
3022 /**
3023  * Verify checksums embedded in the bitstream (could be of either encoded or
3024  * decoded data, depending on the codec) and print an error message on mismatch.
3025  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
3026  * decoder returning an error.
3027  */
3028 #define AV_EF_CRCCHECK (1<<0)
3029 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
3030 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
3031 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
3032 
3033 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
3034 #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
3035 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
3036 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
3037 
3038 
3039  /**
3040  * opaque 64-bit number (generally a PTS) that will be reordered and
3041  * output in AVFrame.reordered_opaque
3042  * - encoding: unused
3043  * - decoding: Set by user.
3044  */
3046 
3047  /**
3048  * Hardware accelerator in use
3049  * - encoding: unused.
3050  * - decoding: Set by libavcodec
3051  */
3053 
3054  /**
3055  * Hardware accelerator context.
3056  * For some hardware accelerators, a global context needs to be
3057  * provided by the user. In that case, this holds display-dependent
3058  * data FFmpeg cannot instantiate itself. Please refer to the
3059  * FFmpeg HW accelerator documentation to know how to fill this
3060  * is. e.g. for VA API, this is a struct vaapi_context.
3061  * - encoding: unused
3062  * - decoding: Set by user
3063  */
3065 
3066  /**
3067  * error
3068  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
3069  * - decoding: unused
3070  */
3072 
3073  /**
3074  * DCT algorithm, see FF_DCT_* below
3075  * - encoding: Set by user.
3076  * - decoding: unused
3077  */
3079 #define FF_DCT_AUTO 0
3080 #define FF_DCT_FASTINT 1
3081 #define FF_DCT_INT 2
3082 #define FF_DCT_MMX 3
3083 #define FF_DCT_ALTIVEC 5
3084 #define FF_DCT_FAAN 6
3085 
3086  /**
3087  * IDCT algorithm, see FF_IDCT_* below.
3088  * - encoding: Set by user.
3089  * - decoding: Set by user.
3090  */
3092 #define FF_IDCT_AUTO 0
3093 #define FF_IDCT_INT 1
3094 #define FF_IDCT_SIMPLE 2
3095 #define FF_IDCT_SIMPLEMMX 3
3096 #define FF_IDCT_ARM 7
3097 #define FF_IDCT_ALTIVEC 8
3098 #if FF_API_ARCH_SH4
3099 #define FF_IDCT_SH4 9
3100 #endif
3101 #define FF_IDCT_SIMPLEARM 10
3102 #if FF_API_UNUSED_MEMBERS
3103 #define FF_IDCT_IPP 13
3104 #endif /* FF_API_UNUSED_MEMBERS */
3105 #define FF_IDCT_XVID 14
3106 #if FF_API_IDCT_XVIDMMX
3107 #define FF_IDCT_XVIDMMX 14
3108 #endif /* FF_API_IDCT_XVIDMMX */
3109 #define FF_IDCT_SIMPLEARMV5TE 16
3110 #define FF_IDCT_SIMPLEARMV6 17
3111 #if FF_API_ARCH_SPARC
3112 #define FF_IDCT_SIMPLEVIS 18
3113 #endif
3114 #define FF_IDCT_FAAN 20
3115 #define FF_IDCT_SIMPLENEON 22
3116 #if FF_API_ARCH_ALPHA
3117 #define FF_IDCT_SIMPLEALPHA 23
3118 #endif
3119 #define FF_IDCT_SIMPLEAUTO 128
3120 
3121  /**
3122  * bits per sample/pixel from the demuxer (needed for huffyuv).
3123  * - encoding: Set by libavcodec.
3124  * - decoding: Set by user.
3125  */
3127 
3128  /**
3129  * Bits per sample/pixel of internal libavcodec pixel/sample format.
3130  * - encoding: set by user.
3131  * - decoding: set by libavcodec.
3132  */
3134 
3135 #if FF_API_LOWRES
3136  /**
3137  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3138  * - encoding: unused
3139  * - decoding: Set by user.
3140  */
3141  int lowres;
3142 #endif
3143 
3144 #if FF_API_CODED_FRAME
3145  /**
3146  * the picture in the bitstream
3147  * - encoding: Set by libavcodec.
3148  * - decoding: unused
3149  *
3150  * @deprecated use the quality factor packet side data instead
3151  */
3153 #endif
3154 
3155  /**
3156  * thread count
3157  * is used to decide how many independent tasks should be passed to execute()
3158  * - encoding: Set by user.
3159  * - decoding: Set by user.
3160  */
3162 
3163  /**
3164  * Which multithreading methods to use.
3165  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
3166  * so clients which cannot provide future frames should not use it.
3167  *
3168  * - encoding: Set by user, otherwise the default is used.
3169  * - decoding: Set by user, otherwise the default is used.
3170  */
3172 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
3173 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
3174 
3175  /**
3176  * Which multithreading methods are in use by the codec.
3177  * - encoding: Set by libavcodec.
3178  * - decoding: Set by libavcodec.
3179  */
3181 
3182  /**
3183  * Set by the client if its custom get_buffer() callback can be called
3184  * synchronously from another thread, which allows faster multithreaded decoding.
3185  * draw_horiz_band() will be called from other threads regardless of this setting.
3186  * Ignored if the default get_buffer() is used.
3187  * - encoding: Set by user.
3188  * - decoding: Set by user.
3189  */
3191 
3192  /**
3193  * The codec may call this to execute several independent things.
3194  * It will return only after finishing all tasks.
3195  * The user may replace this with some multithreaded implementation,
3196  * the default implementation will execute the parts serially.
3197  * @param count the number of things to execute
3198  * - encoding: Set by libavcodec, user can override.
3199  * - decoding: Set by libavcodec, user can override.
3200  */
3201  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
3202 
3203  /**
3204  * The codec may call this to execute several independent things.
3205  * It will return only after finishing all tasks.
3206  * The user may replace this with some multithreaded implementation,
3207  * the default implementation will execute the parts serially.
3208  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
3209  * @param c context passed also to func
3210  * @param count the number of things to execute
3211  * @param arg2 argument passed unchanged to func
3212  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
3213  * @param func function that will be called count times, with jobnr from 0 to count-1.
3214  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
3215  * two instances of func executing at the same time will have the same threadnr.
3216  * @return always 0 currently, but code should handle a future improvement where when any call to func
3217  * returns < 0 no further calls to func may be done and < 0 is returned.
3218  * - encoding: Set by libavcodec, user can override.
3219  * - decoding: Set by libavcodec, user can override.
3220  */
3221  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
3222 
3223  /**
3224  * noise vs. sse weight for the nsse comparison function
3225  * - encoding: Set by user.
3226  * - decoding: unused
3227  */
3229 
3230  /**
3231  * profile
3232  * - encoding: Set by user.
3233  * - decoding: Set by libavcodec.
3234  */
3235  int profile;
3236 #define FF_PROFILE_UNKNOWN -99
3237 #define FF_PROFILE_RESERVED -100
3238 
3239 #define FF_PROFILE_AAC_MAIN 0
3240 #define FF_PROFILE_AAC_LOW 1
3241 #define FF_PROFILE_AAC_SSR 2
3242 #define FF_PROFILE_AAC_LTP 3
3243 #define FF_PROFILE_AAC_HE 4
3244 #define FF_PROFILE_AAC_HE_V2 28
3245 #define FF_PROFILE_AAC_LD 22
3246 #define FF_PROFILE_AAC_ELD 38
3247 #define FF_PROFILE_MPEG2_AAC_LOW 128
3248 #define FF_PROFILE_MPEG2_AAC_HE 131
3249 
3250 #define FF_PROFILE_DNXHD 0
3251 #define FF_PROFILE_DNXHR_LB 1
3252 #define FF_PROFILE_DNXHR_SQ 2
3253 #define FF_PROFILE_DNXHR_HQ 3
3254 #define FF_PROFILE_DNXHR_HQX 4
3255 #define FF_PROFILE_DNXHR_444 5
3256 
3257 #define FF_PROFILE_DTS 20
3258 #define FF_PROFILE_DTS_ES 30
3259 #define FF_PROFILE_DTS_96_24 40
3260 #define FF_PROFILE_DTS_HD_HRA 50
3261 #define FF_PROFILE_DTS_HD_MA 60
3262 #define FF_PROFILE_DTS_EXPRESS 70
3263 
3264 #define FF_PROFILE_MPEG2_422 0
3265 #define FF_PROFILE_MPEG2_HIGH 1
3266 #define FF_PROFILE_MPEG2_SS 2
3267 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
3268 #define FF_PROFILE_MPEG2_MAIN 4
3269 #define FF_PROFILE_MPEG2_SIMPLE 5
3270 
3271 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
3272 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
3273 
3274 #define FF_PROFILE_H264_BASELINE 66
3275 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
3276 #define FF_PROFILE_H264_MAIN 77
3277 #define FF_PROFILE_H264_EXTENDED 88
3278 #define FF_PROFILE_H264_HIGH 100
3279 #define FF_PROFILE_H264_HIGH_10 110
3280 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
3281 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
3282 #define FF_PROFILE_H264_HIGH_422 122
3283 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
3284 #define FF_PROFILE_H264_STEREO_HIGH 128
3285 #define FF_PROFILE_H264_HIGH_444 144
3286 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
3287 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
3288 #define FF_PROFILE_H264_CAVLC_444 44
3289 
3290 #define FF_PROFILE_VC1_SIMPLE 0
3291 #define FF_PROFILE_VC1_MAIN 1
3292 #define FF_PROFILE_VC1_COMPLEX 2
3293 #define FF_PROFILE_VC1_ADVANCED 3
3294 
3295 #define FF_PROFILE_MPEG4_SIMPLE 0
3296 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
3297 #define FF_PROFILE_MPEG4_CORE 2
3298 #define FF_PROFILE_MPEG4_MAIN 3
3299 #define FF_PROFILE_MPEG4_N_BIT 4
3300 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
3301 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
3302 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
3303 #define FF_PROFILE_MPEG4_HYBRID 8
3304 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
3305 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
3306 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
3307 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
3308 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
3309 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
3310 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
3311 
3312 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
3313 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
3314 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
3315 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
3316 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
3317 
3318 #define FF_PROFILE_VP9_0 0
3319 #define FF_PROFILE_VP9_1 1
3320 #define FF_PROFILE_VP9_2 2
3321 #define FF_PROFILE_VP9_3 3
3322 
3323 #define FF_PROFILE_HEVC_MAIN 1
3324 #define FF_PROFILE_HEVC_MAIN_10 2
3325 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
3326 #define FF_PROFILE_HEVC_REXT 4
3327 
3328  /**
3329  * level
3330  * - encoding: Set by user.
3331  * - decoding: Set by libavcodec.
3332  */
3333  int level;
3334 #define FF_LEVEL_UNKNOWN -99
3335 
3336  /**
3337  * Skip loop filtering for selected frames.
3338  * - encoding: unused
3339  * - decoding: Set by user.
3340  */
3342 
3343  /**
3344  * Skip IDCT/dequantization for selected frames.
3345  * - encoding: unused
3346  * - decoding: Set by user.
3347  */
3349 
3350  /**
3351  * Skip decoding for selected frames.
3352  * - encoding: unused
3353  * - decoding: Set by user.
3354  */
3356 
3357  /**
3358  * Header containing style information for text subtitles.
3359  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3360  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3361  * the Format line following. It shouldn't include any Dialogue line.
3362  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3363  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3364  */
3367 
3368 #if FF_API_ERROR_RATE
3369  /**
3370  * @deprecated use the 'error_rate' private AVOption of the mpegvideo
3371  * encoders
3372  */
3375 #endif
3376 
3377 #if FF_API_VBV_DELAY
3378  /**
3379  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3380  * Used for compliant TS muxing.
3381  * - encoding: Set by libavcodec.
3382  * - decoding: unused.
3383  * @deprecated this value is now exported as a part of
3384  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3385  */
3387  uint64_t vbv_delay;
3388 #endif
3389 
3390 #if FF_API_SIDEDATA_ONLY_PKT
3391  /**
3392  * Encoding only and set by default. Allow encoders to output packets
3393  * that do not contain any encoded data, only side data.
3394  *
3395  * Some encoders need to output such packets, e.g. to update some stream
3396  * parameters at the end of encoding.
3397  *
3398  * @deprecated this field disables the default behaviour and
3399  * it is kept only for compatibility.
3400  */
3403 #endif
3404 
3405  /**
3406  * Audio only. The number of "priming" samples (padding) inserted by the
3407  * encoder at the beginning of the audio. I.e. this number of leading
3408  * decoded samples must be discarded by the caller to get the original audio
3409  * without leading padding.
3410  *
3411  * - decoding: unused
3412  * - encoding: Set by libavcodec. The timestamps on the output packets are
3413  * adjusted by the encoder so that they always refer to the
3414  * first sample of the data actually contained in the packet,
3415  * including any added padding. E.g. if the timebase is
3416  * 1/samplerate and the timestamp of the first input sample is
3417  * 0, the timestamp of the first output packet will be
3418  * -initial_padding.
3419  */
3421 
3422  /**
3423  * - decoding: For codecs that store a framerate value in the compressed
3424  * bitstream, the decoder may export it here. { 0, 1} when
3425  * unknown.
3426  * - encoding: May be used to signal the framerate of CFR content to an
3427  * encoder.
3428  */
3430 
3431  /**
3432  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3433  * - encoding: unused.
3434  * - decoding: Set by libavcodec before calling get_format()
3435  */
3437 
3438  /**
3439  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3440  * - encoding unused.
3441  * - decoding set by user.
3442  */
3444 
3445  /**
3446  * AVCodecDescriptor
3447  * - encoding: unused.
3448  * - decoding: set by libavcodec.
3449  */
3451 
3452 #if !FF_API_LOWRES
3453  /**
3454  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3455  * - encoding: unused
3456  * - decoding: Set by user.
3457  */
3458  int lowres;
3459 #endif
3460 
3461  /**
3462  * Current statistics for PTS correction.
3463  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3464  * - encoding: unused
3465  */
3466  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3467  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3468  int64_t pts_correction_last_pts; /// PTS of the last frame
3469  int64_t pts_correction_last_dts; /// DTS of the last frame
3470 
3471  /**
3472  * Character encoding of the input subtitles file.
3473  * - decoding: set by user
3474  * - encoding: unused
3475  */
3477 
3478  /**
3479  * Subtitles character encoding mode. Formats or codecs might be adjusting
3480  * this setting (if they are doing the conversion themselves for instance).
3481  * - decoding: set by libavcodec
3482  * - encoding: unused
3483  */
3485 #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)
3486 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3487 #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
3488 
3489  /**
3490  * Skip processing alpha if supported by codec.
3491  * Note that if the format uses pre-multiplied alpha (common with VP6,
3492  * and recommended due to better video quality/compression)
3493  * the image will look as if alpha-blended onto a black background.
3494  * However for formats that do not use pre-multiplied alpha
3495  * there might be serious artefacts (though e.g. libswscale currently
3496  * assumes pre-multiplied alpha anyway).
3497  *
3498  * - decoding: set by user
3499  * - encoding: unused
3500  */
3502 
3503  /**
3504  * Number of samples to skip after a discontinuity
3505  * - decoding: unused
3506  * - encoding: set by libavcodec
3507  */
3509 
3510 #if !FF_API_DEBUG_MV
3511  /**
3512  * debug motion vectors
3513  * - encoding: Set by user.
3514  * - decoding: Set by user.
3515  */
3516  int debug_mv;
3517 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3518 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3519 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3520 #endif
3521 
3522  /**
3523  * custom intra quantization matrix
3524  * - encoding: Set by user, can be NULL.
3525  * - decoding: unused.
3526  */
3528 
3529  /**
3530  * dump format separator.
3531  * can be ", " or "\n " or anything else
3532  * - encoding: Set by user.
3533  * - decoding: Set by user.
3534  */
3536 
3537  /**
3538  * ',' separated list of allowed decoders.
3539  * If NULL then all are allowed
3540  * - encoding: unused
3541  * - decoding: set by user
3542  */
3544 
3545  /*
3546  * Properties of the stream that gets decoded
3547  * - encoding: unused
3548  * - decoding: set by libavcodec
3549  */
3550  unsigned properties;
3551 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3552 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3553 
3554  /**
3555  * Additional data associated with the entire coded stream.
3556  *
3557  * - decoding: unused
3558  * - encoding: may be set by libavcodec after avcodec_open2().
3559  */
3562 
3563  /**
3564  * A reference to the AVHWFramesContext describing the input (for encoding)
3565  * or output (decoding) frames. The reference is set by the caller and
3566  * afterwards owned (and freed) by libavcodec - it should never be read by
3567  * the caller after being set.
3568  *
3569  * - decoding: This field should be set by the caller from the get_format()
3570  * callback. The previous reference (if any) will always be
3571  * unreffed by libavcodec before the get_format() call.
3572  *
3573  * If the default get_buffer2() is used with a hwaccel pixel
3574  * format, then this AVHWFramesContext will be used for
3575  * allocating the frame buffers.
3576  *
3577  * - encoding: For hardware encoders configured to use a hwaccel pixel
3578  * format, this field should be set by the caller to a reference
3579  * to the AVHWFramesContext describing input frames.
3580  * AVHWFramesContext.format must be equal to
3581  * AVCodecContext.pix_fmt.
3582  *
3583  * This field should be set before avcodec_open2() is called.
3584  */
3586 
3587  /**
3588  * Control the form of AVSubtitle.rects[N]->ass
3589  * - decoding: set by user
3590  * - encoding: unused
3591  */
3593 #define FF_SUB_TEXT_FMT_ASS 0
3594 #if FF_API_ASS_TIMING
3595 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3596 #endif
3597 
3598  /**
3599  * Audio only. The amount of padding (in samples) appended by the encoder to
3600  * the end of the audio. I.e. this number of decoded samples must be
3601  * discarded by the caller from the end of the stream to get the original
3602  * audio without any trailing padding.
3603  *
3604  * - decoding: unused
3605  * - encoding: unused
3606  */
3608 
3609  /**
3610  * The number of pixels per image to maximally accept.
3611  *
3612  * - decoding: set by user
3613  * - encoding: set by user
3614  */
3615  int64_t max_pixels;
3616 
3617  /**
3618  * A reference to the AVHWDeviceContext describing the device which will
3619  * be used by a hardware encoder/decoder. The reference is set by the
3620  * caller and afterwards owned (and freed) by libavcodec.
3621  *
3622  * This should be used if either the codec device does not require
3623  * hardware frames or any that are used are to be allocated internally by
3624  * libavcodec. If the user wishes to supply any of the frames used as
3625  * encoder input or decoder output then hw_frames_ctx should be used
3626  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3627  * field will be ignored while decoding the associated stream segment, but
3628  * may again be used on a following one after another get_format() call.
3629  *
3630  * For both encoders and decoders this field should be set before
3631  * avcodec_open2() is called and must not be written to thereafter.
3632  *
3633  * Note that some decoders may require this field to be set initially in
3634  * order to support hw_frames_ctx at all - in that case, all frames
3635  * contexts used must be created on the same device.
3636  */
3638 
3639  /**
3640  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3641  * decoding (if active).
3642  * - encoding: unused
3643  * - decoding: Set by user (either before avcodec_open2(), or in the
3644  * AVCodecContext.get_format callback)
3645  */
3647 } AVCodecContext;
3648 
3651 
3654 
3655 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3656 
3657 int av_codec_get_lowres(const AVCodecContext *avctx);
3658 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3659 
3660 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3661 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3662 
3663 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3664 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3665 
3666 /**
3667  * AVProfile.
3668  */
3669 typedef struct AVProfile {
3670  int profile;
3671  const char *name; ///< short name for the profile
3672 } AVProfile;
3673 
3674 typedef struct AVCodecDefault AVCodecDefault;
3675 
3676 struct AVSubtitle;
3677 
3678 /**
3679  * AVCodec.
3680  */
3681 typedef struct AVCodec {
3682  /**
3683  * Name of the codec implementation.
3684  * The name is globally unique among encoders and among decoders (but an
3685  * encoder and a decoder can share the same name).
3686  * This is the primary way to find a codec from the user perspective.
3687  */
3688  const char *name;
3689  /**
3690  * Descriptive name for the codec, meant to be more human readable than name.
3691  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3692  */
3693  const char *long_name;
3696  /**
3697  * Codec capabilities.
3698  * see AV_CODEC_CAP_*
3699  */
3701  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3702  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3703  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3704  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3705  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3706  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3707  const AVClass *priv_class; ///< AVClass for the private context
3708  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3709 
3710  /*****************************************************************
3711  * No fields below this line are part of the public API. They
3712  * may not be used outside of libavcodec and can be changed and
3713  * removed at will.
3714  * New public fields should be added right above.
3715  *****************************************************************
3716  */
3718  struct AVCodec *next;
3719  /**
3720  * @name Frame-level threading support functions
3721  * @{
3722  */
3723  /**
3724  * If defined, called on thread contexts when they are created.
3725  * If the codec allocates writable tables in init(), re-allocate them here.
3726  * priv_data will be set to a copy of the original.
3727  */
3729  /**
3730  * Copy necessary context variables from a previous thread context to the current one.
3731  * If not defined, the next thread will start automatically; otherwise, the codec
3732  * must call ff_thread_finish_setup().
3733  *
3734  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3735  */
3737  /** @} */
3738 
3739  /**
3740  * Private codec-specific defaults.
3741  */
3743 
3744  /**
3745  * Initialize codec static data, called from avcodec_register().
3746  */
3747  void (*init_static_data)(struct AVCodec *codec);
3748 
3750  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3751  const struct AVSubtitle *sub);
3752  /**
3753  * Encode data to an AVPacket.
3754  *
3755  * @param avctx codec context
3756  * @param avpkt output AVPacket (may contain a user-provided buffer)
3757  * @param[in] frame AVFrame containing the raw data to be encoded
3758  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3759  * non-empty packet was returned in avpkt.
3760  * @return 0 on success, negative error code on failure
3761  */
3762  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3763  int *got_packet_ptr);
3764  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3766  /**
3767  * Encode API with decoupled packet/frame dataflow. The API is the
3768  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3769  * that:
3770  * - never called if the codec is closed or the wrong type,
3771  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3772  * - only one drain frame is ever passed down,
3773  */
3776 
3777  /**
3778  * Decode API with decoupled packet/frame dataflow. This function is called
3779  * to get one output frame. It should call ff_decode_get_packet() to obtain
3780  * input data.
3781  */
3783  /**
3784  * Flush buffers.
3785  * Will be called when seeking
3786  */
3788  /**
3789  * Internal codec capabilities.
3790  * See FF_CODEC_CAP_* in internal.h
3791  */
3793 
3794  /**
3795  * Decoding only, a comma-separated list of bitstream filters to apply to
3796  * packets before decoding.
3797  */
3798  const char *bsfs;
3799 } AVCodec;
3800 
3801 int av_codec_get_max_lowres(const AVCodec *codec);
3802 
3803 struct MpegEncContext;
3804 
3805 /**
3806  * @defgroup lavc_hwaccel AVHWAccel
3807  * @{
3808  */
3809 typedef struct AVHWAccel {
3810  /**
3811  * Name of the hardware accelerated codec.
3812  * The name is globally unique among encoders and among decoders (but an
3813  * encoder and a decoder can share the same name).
3814  */
3815  const char *name;
3816 
3817  /**
3818  * Type of codec implemented by the hardware accelerator.
3819  *
3820  * See AVMEDIA_TYPE_xxx
3821  */
3823 
3824  /**
3825  * Codec implemented by the hardware accelerator.
3826  *
3827  * See AV_CODEC_ID_xxx
3828  */
3830 
3831  /**
3832  * Supported pixel format.
3833  *
3834  * Only hardware accelerated formats are supported here.
3835  */
3837 
3838  /**
3839  * Hardware accelerated codec capabilities.
3840  * see HWACCEL_CODEC_CAP_*
3841  */
3843 
3844  /*****************************************************************
3845  * No fields below this line are part of the public API. They
3846  * may not be used outside of libavcodec and can be changed and
3847  * removed at will.
3848  * New public fields should be added right above.
3849  *****************************************************************
3850  */
3851  struct AVHWAccel *next;
3852 
3853  /**
3854  * Allocate a custom buffer
3855  */
3857 
3858  /**
3859  * Called at the beginning of each frame or field picture.
3860  *
3861  * Meaningful frame information (codec specific) is guaranteed to
3862  * be parsed at this point. This function is mandatory.
3863  *
3864  * Note that buf can be NULL along with buf_size set to 0.
3865  * Otherwise, this means the whole frame is available at this point.
3866  *
3867  * @param avctx the codec context
3868  * @param buf the frame data buffer base
3869  * @param buf_size the size of the frame in bytes
3870  * @return zero if successful, a negative value otherwise
3871  */
3872  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3873 
3874  /**
3875  * Callback for each slice.
3876  *
3877  * Meaningful slice information (codec specific) is guaranteed to
3878  * be parsed at this point. This function is mandatory.
3879  * The only exception is XvMC, that works on MB level.
3880  *
3881  * @param avctx the codec context
3882  * @param buf the slice data buffer base
3883  * @param buf_size the size of the slice in bytes
3884  * @return zero if successful, a negative value otherwise
3885  */
3886  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3887 
3888  /**
3889  * Called at the end of each frame or field picture.
3890  *
3891  * The whole picture is parsed at this point and can now be sent
3892  * to the hardware accelerator. This function is mandatory.
3893  *
3894  * @param avctx the codec context
3895  * @return zero if successful, a negative value otherwise
3896  */
3898 
3899  /**
3900  * Size of per-frame hardware accelerator private data.
3901  *
3902  * Private data is allocated with av_mallocz() before
3903  * AVCodecContext.get_buffer() and deallocated after
3904  * AVCodecContext.release_buffer().
3905  */
3907 
3908  /**
3909  * Called for every Macroblock in a slice.
3910  *
3911  * XvMC uses it to replace the ff_mpv_decode_mb().
3912  * Instead of decoding to raw picture, MB parameters are
3913  * stored in an array provided by the video driver.
3914  *
3915  * @param s the mpeg context
3916  */
3918 
3919  /**
3920  * Initialize the hwaccel private data.
3921  *
3922  * This will be called from ff_get_format(), after hwaccel and
3923  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3924  * is allocated.
3925  */
3927 
3928  /**
3929  * Uninitialize the hwaccel private data.
3930  *
3931  * This will be called from get_format() or avcodec_close(), after hwaccel
3932  * and hwaccel_context are already uninitialized.
3933  */
3935 
3936  /**
3937  * Size of the private data to allocate in
3938  * AVCodecInternal.hwaccel_priv_data.
3939  */
3941 
3942  /**
3943  * Internal hwaccel capabilities.
3944  */
3946 } AVHWAccel;
3947 
3948 /**
3949  * Hardware acceleration should be used for decoding even if the codec level
3950  * used is unknown or higher than the maximum supported level reported by the
3951  * hardware driver.
3952  *
3953  * It's generally a good idea to pass this flag unless you have a specific
3954  * reason not to, as hardware tends to under-report supported levels.
3955  */
3956 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3957 
3958 /**
3959  * Hardware acceleration can output YUV pixel formats with a different chroma
3960  * sampling than 4:2:0 and/or other than 8 bits per component.
3961  */
3962 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3963 
3964 /**
3965  * @}
3966  */
3967 
3968 #if FF_API_AVPICTURE
3969 /**
3970  * @defgroup lavc_picture AVPicture
3971  *
3972  * Functions for working with AVPicture
3973  * @{
3974  */
3975 
3976 /**
3977  * Picture data structure.
3978  *
3979  * Up to four components can be stored into it, the last component is
3980  * alpha.
3981  * @deprecated use AVFrame or imgutils functions instead
3982  */
3983 typedef struct AVPicture {
3985  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3987  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3988 } AVPicture;
3989 
3990 /**
3991  * @}
3992  */
3993 #endif
3994 
3997 
3998  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3999 
4000  /**
4001  * Plain text, the text field must be set by the decoder and is
4002  * authoritative. ass and pict fields may contain approximations.
4003  */
4005 
4006  /**
4007  * Formatted text, the ass field must be set by the decoder and is
4008  * authoritative. pict and text fields may contain approximations.
4009  */
4011 };
4012 
4013 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
4014 
4015 typedef struct AVSubtitleRect {
4016  int x; ///< top left corner of pict, undefined when pict is not set
4017  int y; ///< top left corner of pict, undefined when pict is not set
4018  int w; ///< width of pict, undefined when pict is not set
4019  int h; ///< height of pict, undefined when pict is not set
4020  int nb_colors; ///< number of colors in pict, undefined when pict is not set
4021 
4022 #if FF_API_AVPICTURE
4023  /**
4024  * @deprecated unused
4025  */
4028 #endif
4029  /**
4030  * data+linesize for the bitmap of this subtitle.
4031  * Can be set for text/ass as well once they are rendered.
4032  */
4034  int linesize[4];
4035 
4037 
4038  char *text; ///< 0 terminated plain UTF-8 text
4039 
4040  /**
4041  * 0 terminated ASS/SSA compatible event line.
4042  * The presentation of this is unaffected by the other values in this
4043  * struct.
4044  */
4045  char *ass;
4046 
4047  int flags;
4048 } AVSubtitleRect;
4049 
4050 typedef struct AVSubtitle {
4051  uint16_t format; /* 0 = graphics */
4052  uint32_t start_display_time; /* relative to packet pts, in ms */
4053  uint32_t end_display_time; /* relative to packet pts, in ms */
4054  unsigned num_rects;
4056  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
4057 } AVSubtitle;
4058 
4059 /**
4060  * This struct describes the properties of an encoded stream.
4061  *
4062  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
4063  * be allocated with avcodec_parameters_alloc() and freed with
4064  * avcodec_parameters_free().
4065  */
4066 typedef struct AVCodecParameters {
4067  /**
4068  * General type of the encoded data.
4069  */
4071  /**
4072  * Specific type of the encoded data (the codec used).
4073  */
4075  /**
4076  * Additional information about the codec (corresponds to the AVI FOURCC).
4077  */
4078  uint32_t codec_tag;
4079 
4080  /**
4081  * Extra binary data needed for initializing the decoder, codec-dependent.
4082  *
4083  * Must be allocated with av_malloc() and will be freed by
4084  * avcodec_parameters_free(). The allocated size of extradata must be at
4085  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
4086  * bytes zeroed.
4087  */
4089  /**
4090  * Size of the extradata content in bytes.
4091  */
4093 
4094  /**
4095  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
4096  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
4097  */
4098  int format;
4099 
4100  /**
4101  * The average bitrate of the encoded data (in bits per second).
4102  */
4103  int64_t bit_rate;
4104 
4105  /**
4106  * The number of bits per sample in the codedwords.
4107  *
4108  * This is basically the bitrate per sample. It is mandatory for a bunch of
4109  * formats to actually decode them. It's the number of bits for one sample in
4110  * the actual coded bitstream.
4111  *
4112  * This could be for example 4 for ADPCM
4113  * For PCM formats this matches bits_per_raw_sample
4114  * Can be 0
4115  */
4117 
4118  /**
4119  * This is the number of valid bits in each output sample. If the
4120  * sample format has more bits, the least significant bits are additional
4121  * padding bits, which are always 0. Use right shifts to reduce the sample
4122  * to its actual size. For example, audio formats with 24 bit samples will
4123  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
4124  * To get the original sample use "(int32_t)sample >> 8"."
4125  *
4126  * For ADPCM this might be 12 or 16 or similar
4127  * Can be 0
4128  */
4130 
4131  /**
4132  * Codec-specific bitstream restrictions that the stream conforms to.
4133  */
4134  int profile;
4135  int level;
4136 
4137  /**
4138  * Video only. The dimensions of the video frame in pixels.
4139  */
4140  int width;
4141  int height;
4142 
4143  /**
4144  * Video only. The aspect ratio (width / height) which a single pixel
4145  * should have when displayed.
4146  *
4147  * When the aspect ratio is unknown / undefined, the numerator should be
4148  * set to 0 (the denominator may have any value).
4149  */
4151 
4152  /**
4153  * Video only. The order of the fields in interlaced video.
4154  */
4156 
4157  /**
4158  * Video only. Additional colorspace characteristics.
4159  */
4165 
4166  /**
4167  * Video only. Number of delayed frames.
4168  */
4170 
4171  /**
4172  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4173  * unknown or unspecified, otherwise the number of bits set must be equal to
4174  * the channels field.
4175  */
4176  uint64_t channel_layout;
4177  /**
4178  * Audio only. The number of audio channels.
4179  */
4181  /**
4182  * Audio only. The number of audio samples per second.
4183  */
4185  /**
4186  * Audio only. The number of bytes per coded audio frame, required by some
4187  * formats.
4188  *
4189  * Corresponds to nBlockAlign in WAVEFORMATEX.
4190  */
4192  /**
4193  * Audio only. Audio frame size, if known. Required by some formats to be static.
4194  */
4196 
4197  /**
4198  * Audio only. The amount of padding (in samples) inserted by the encoder at
4199  * the beginning of the audio. I.e. this number of leading decoded samples
4200  * must be discarded by the caller to get the original audio without leading
4201  * padding.
4202  */
4204  /**
4205  * Audio only. The amount of padding (in samples) appended by the encoder to
4206  * the end of the audio. I.e. this number of decoded samples must be
4207  * discarded by the caller from the end of the stream to get the original
4208  * audio without any trailing padding.
4209  */
4211  /**
4212  * Audio only. Number of samples to skip after a discontinuity.
4213  */
4216 
4217 /**
4218  * If c is NULL, returns the first registered codec,
4219  * if c is non-NULL, returns the next registered codec after c,
4220  * or NULL if c is the last one.
4221  */
4222 AVCodec *av_codec_next(const AVCodec *c);
4223 
4224 /**
4225  * Return the LIBAVCODEC_VERSION_INT constant.
4226  */
4227 unsigned avcodec_version(void);
4228 
4229 /**
4230  * Return the libavcodec build-time configuration.
4231  */
4232 const char *avcodec_configuration(void);
4233 
4234 /**
4235  * Return the libavcodec license.
4236  */
4237 const char *avcodec_license(void);
4238 
4239 /**
4240  * Register the codec codec and initialize libavcodec.
4241  *
4242  * @warning either this function or avcodec_register_all() must be called
4243  * before any other libavcodec functions.
4244  *
4245  * @see avcodec_register_all()
4246  */
4247 void avcodec_register(AVCodec *codec);
4248 
4249 /**
4250  * Register all the codecs, parsers and bitstream filters which were enabled at
4251  * configuration time. If you do not call this function you can select exactly
4252  * which formats you want to support, by using the individual registration
4253  * functions.
4254  *
4255  * @see avcodec_register
4256  * @see av_register_codec_parser
4257  * @see av_register_bitstream_filter
4258  */
4259 void avcodec_register_all(void);
4260 
4261 /**
4262  * Allocate an AVCodecContext and set its fields to default values. The
4263  * resulting struct should be freed with avcodec_free_context().
4264  *
4265  * @param codec if non-NULL, allocate private data and initialize defaults
4266  * for the given codec. It is illegal to then call avcodec_open2()
4267  * with a different codec.
4268  * If NULL, then the codec-specific defaults won't be initialized,
4269  * which may result in suboptimal default settings (this is
4270  * important mainly for encoders, e.g. libx264).
4271  *
4272  * @return An AVCodecContext filled with default values or NULL on failure.
4273  */
4275 
4276 /**
4277  * Free the codec context and everything associated with it and write NULL to
4278  * the provided pointer.
4279  */
4280 void avcodec_free_context(AVCodecContext **avctx);
4281 
4282 #if FF_API_GET_CONTEXT_DEFAULTS
4283 /**
4284  * @deprecated This function should not be used, as closing and opening a codec
4285  * context multiple time is not supported. A new codec context should be
4286  * allocated for each new use.
4287  */
4289 #endif
4290 
4291 /**
4292  * Get the AVClass for AVCodecContext. It can be used in combination with
4293  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4294  *
4295  * @see av_opt_find().
4296  */
4297 const AVClass *avcodec_get_class(void);
4298 
4299 #if FF_API_COPY_CONTEXT
4300 /**
4301  * Get the AVClass for AVFrame. It can be used in combination with
4302  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4303  *
4304  * @see av_opt_find().
4305  */
4306 const AVClass *avcodec_get_frame_class(void);
4307 
4308 /**
4309  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4310  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4311  *
4312  * @see av_opt_find().
4313  */
4315 
4316 /**
4317  * Copy the settings of the source AVCodecContext into the destination
4318  * AVCodecContext. The resulting destination codec context will be
4319  * unopened, i.e. you are required to call avcodec_open2() before you
4320  * can use this AVCodecContext to decode/encode video/audio data.
4321  *
4322  * @param dest target codec context, should be initialized with
4323  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4324  * @param src source codec context
4325  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4326  *
4327  * @deprecated The semantics of this function are ill-defined and it should not
4328  * be used. If you need to transfer the stream parameters from one codec context
4329  * to another, use an intermediate AVCodecParameters instance and the
4330  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4331  * functions.
4332  */
4335 #endif
4336 
4337 /**
4338  * Allocate a new AVCodecParameters and set its fields to default values
4339  * (unknown/invalid/0). The returned struct must be freed with
4340  * avcodec_parameters_free().
4341  */
4343 
4344 /**
4345  * Free an AVCodecParameters instance and everything associated with it and
4346  * write NULL to the supplied pointer.
4347  */
4349 
4350 /**
4351  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4352  * replaced with newly allocated duplicates of the corresponding fields in src.
4353  *
4354  * @return >= 0 on success, a negative AVERROR code on failure.
4355  */
4357 
4358 /**
4359  * Fill the parameters struct based on the values from the supplied codec
4360  * context. Any allocated fields in par are freed and replaced with duplicates
4361  * of the corresponding fields in codec.
4362  *
4363  * @return >= 0 on success, a negative AVERROR code on failure
4364  */
4366  const AVCodecContext *codec);
4367 
4368 /**
4369  * Fill the codec context based on the values from the supplied codec
4370  * parameters. Any allocated fields in codec that have a corresponding field in
4371  * par are freed and replaced with duplicates of the corresponding field in par.
4372  * Fields in codec that do not have a counterpart in par are not touched.
4373  *
4374  * @return >= 0 on success, a negative AVERROR code on failure.
4375  */
4377  const AVCodecParameters *par);
4378 
4379 /**
4380  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4381  * function the context has to be allocated with avcodec_alloc_context3().
4382  *
4383  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4384  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4385  * retrieving a codec.
4386  *
4387  * @warning This function is not thread safe!
4388  *
4389  * @note Always call this function before using decoding routines (such as
4390  * @ref avcodec_receive_frame()).
4391  *
4392  * @code
4393  * avcodec_register_all();
4394  * av_dict_set(&opts, "b", "2.5M", 0);
4395  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4396  * if (!codec)
4397  * exit(1);
4398  *
4399  * context = avcodec_alloc_context3(codec);
4400  *
4401  * if (avcodec_open2(context, codec, opts) < 0)
4402  * exit(1);
4403  * @endcode
4404  *
4405  * @param avctx The context to initialize.
4406  * @param codec The codec to open this context for. If a non-NULL codec has been
4407  * previously passed to avcodec_alloc_context3() or
4408  * for this context, then this parameter MUST be either NULL or
4409  * equal to the previously passed codec.
4410  * @param options A dictionary filled with AVCodecContext and codec-private options.
4411  * On return this object will be filled with options that were not found.
4412  *
4413  * @return zero on success, a negative value on error
4414  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4415  * av_dict_set(), av_opt_find().
4416  */
4417 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4418 
4419 /**
4420  * Close a given AVCodecContext and free all the data associated with it
4421  * (but not the AVCodecContext itself).
4422  *
4423  * Calling this function on an AVCodecContext that hasn't been opened will free
4424  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4425  * codec. Subsequent calls will do nothing.
4426  *
4427  * @note Do not use this function. Use avcodec_free_context() to destroy a
4428  * codec context (either open or closed). Opening and closing a codec context
4429  * multiple times is not supported anymore -- use multiple codec contexts
4430  * instead.
4431  */
4432 int avcodec_close(AVCodecContext *avctx);
4433 
4434 /**
4435  * Free all allocated data in the given subtitle struct.
4436  *
4437  * @param sub AVSubtitle to free.
4438  */
4439 void avsubtitle_free(AVSubtitle *sub);
4440 
4441 /**
4442  * @}
4443  */
4444 
4445 /**
4446  * @addtogroup lavc_packet
4447  * @{
4448  */
4449 
4450 /**
4451  * Allocate an AVPacket and set its fields to default values. The resulting
4452  * struct must be freed using av_packet_free().
4453  *
4454  * @return An AVPacket filled with default values or NULL on failure.
4455  *
4456  * @note this only allocates the AVPacket itself, not the data buffers. Those
4457  * must be allocated through other means such as av_new_packet.
4458  *
4459  * @see av_new_packet
4460  */
4461 AVPacket *av_packet_alloc(void);
4462 
4463 /**
4464  * Create a new packet that references the same data as src.
4465  *
4466  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4467  *
4468  * @return newly created AVPacket on success, NULL on error.
4469  *
4470  * @see av_packet_alloc
4471  * @see av_packet_ref
4472  */
4474 
4475 /**
4476  * Free the packet, if the packet is reference counted, it will be
4477  * unreferenced first.
4478  *
4479  * @param pkt packet to be freed. The pointer will be set to NULL.
4480  * @note passing NULL is a no-op.
4481  */
4482 void av_packet_free(AVPacket **pkt);
4483 
4484 /**
4485  * Initialize optional fields of a packet with default values.
4486  *
4487  * Note, this does not touch the data and size members, which have to be
4488  * initialized separately.
4489  *
4490  * @param pkt packet
4491  */
4492 void av_init_packet(AVPacket *pkt);
4493 
4494 /**
4495  * Allocate the payload of a packet and initialize its fields with
4496  * default values.
4497  *
4498  * @param pkt packet
4499  * @param size wanted payload size
4500  * @return 0 if OK, AVERROR_xxx otherwise
4501  */
4502 int av_new_packet(AVPacket *pkt, int size);
4503 
4504 /**
4505  * Reduce packet size, correctly zeroing padding
4506  *
4507  * @param pkt packet
4508  * @param size new size
4509  */
4510 void av_shrink_packet(AVPacket *pkt, int size);
4511 
4512 /**
4513  * Increase packet size, correctly zeroing padding
4514  *
4515  * @param pkt packet
4516  * @param grow_by number of bytes by which to increase the size of the packet
4517  */
4518 int av_grow_packet(AVPacket *pkt, int grow_by);
4519 
4520 /**
4521  * Initialize a reference-counted packet from av_malloc()ed data.
4522  *
4523  * @param pkt packet to be initialized. This function will set the data, size,
4524  * buf and destruct fields, all others are left untouched.
4525  * @param data Data allocated by av_malloc() to be used as packet data. If this
4526  * function returns successfully, the data is owned by the underlying AVBuffer.
4527  * The caller may not access the data through other means.
4528  * @param size size of data in bytes, without the padding. I.e. the full buffer
4529  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4530  *
4531  * @return 0 on success, a negative AVERROR on error
4532  */
4534 
4535 #if FF_API_AVPACKET_OLD_API
4536 /**
4537  * @warning This is a hack - the packet memory allocation stuff is broken. The
4538  * packet is allocated if it was not really allocated.
4539  *
4540  * @deprecated Use av_packet_ref
4541  */
4543 int av_dup_packet(AVPacket *pkt);
4544 /**
4545  * Copy packet, including contents
4546  *
4547  * @return 0 on success, negative AVERROR on fail
4548  */
4549 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4550 
4551 /**
4552  * Copy packet side data
4553  *
4554  * @return 0 on success, negative AVERROR on fail
4555  */
4556 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4557 
4558 /**
4559  * Free a packet.
4560  *
4561  * @deprecated Use av_packet_unref
4562  *
4563  * @param pkt packet to free
4564  */
4566 void av_free_packet(AVPacket *pkt);
4567 #endif
4568 /**
4569  * Allocate new information of a packet.
4570  *
4571  * @param pkt packet
4572  * @param type side information type
4573  * @param size side information size
4574  * @return pointer to fresh allocated data or NULL otherwise
4575  */
4577  int size);
4578 
4579 /**
4580  * Wrap an existing array as a packet side data.
4581  *
4582  * @param pkt packet
4583  * @param type side information type
4584  * @param data the side data array. It must be allocated with the av_malloc()
4585  * family of functions. The ownership of the data is transferred to
4586  * pkt.
4587  * @param size side information size
4588  * @return a non-negative number on success, a negative AVERROR code on
4589  * failure. On failure, the packet is unchanged and the data remains
4590  * owned by the caller.
4591  */
4593  uint8_t *data, size_t size);
4594 
4595 /**
4596  * Shrink the already allocated side data buffer
4597  *
4598  * @param pkt packet
4599  * @param type side information type
4600  * @param size new side information size
4601  * @return 0 on success, < 0 on failure
4602  */
4604  int size);
4605 
4606 /**
4607  * Get side information from packet.
4608  *
4609  * @param pkt packet
4610  * @param type desired side information type
4611  * @param size pointer for side information size to store (optional)
4612  * @return pointer to data if present or NULL otherwise
4613  */
4615  int *size);
4616 
4617 #if FF_API_MERGE_SD_API
4620 
4623 #endif
4624 
4626 
4627 /**
4628  * Pack a dictionary for use in side_data.
4629  *
4630  * @param dict The dictionary to pack.
4631  * @param size pointer to store the size of the returned data
4632  * @return pointer to data if successful, NULL otherwise
4633  */
4635 /**
4636  * Unpack a dictionary from side_data.
4637  *
4638  * @param data data from side_data
4639  * @param size size of the data
4640  * @param dict the metadata storage dictionary
4641  * @return 0 on success, < 0 on failure
4642  */
4643 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4644 
4645 
4646 /**
4647  * Convenience function to free all the side data stored.
4648  * All the other fields stay untouched.
4649  *
4650  * @param pkt packet
4651  */
4653 
4654 /**
4655  * Setup a new reference to the data described by a given packet
4656  *
4657  * If src is reference-counted, setup dst as a new reference to the
4658  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4659  * data from src into it.
4660  *
4661  * All the other fields are copied from src.
4662  *
4663  * @see av_packet_unref
4664  *
4665  * @param dst Destination packet
4666  * @param src Source packet
4667  *
4668  * @return 0 on success, a negative AVERROR on error.
4669  */
4670 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4671 
4672 /**
4673  * Wipe the packet.
4674  *
4675  * Unreference the buffer referenced by the packet and reset the
4676  * remaining packet fields to their default values.
4677  *
4678  * @param pkt The packet to be unreferenced.
4679  */
4681 
4682 /**
4683  * Move every field in src to dst and reset src.
4684  *
4685  * @see av_packet_unref
4686  *
4687  * @param src Source packet, will be reset
4688  * @param dst Destination packet
4689  */
4691 
4692 /**
4693  * Copy only "properties" fields from src to dst.
4694  *
4695  * Properties for the purpose of this function are all the fields
4696  * beside those related to the packet data (buf, data, size)
4697  *
4698  * @param dst Destination packet
4699  * @param src Source packet
4700  *
4701  * @return 0 on success AVERROR on failure.
4702  */
4703 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4704 
4705 /**
4706  * Convert valid timing fields (timestamps / durations) in a packet from one
4707  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4708  * ignored.
4709  *
4710  * @param pkt packet on which the conversion will be performed
4711  * @param tb_src source timebase, in which the timing fields in pkt are
4712  * expressed
4713  * @param tb_dst destination timebase, to which the timing fields will be
4714  * converted
4715  */
4716 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4717 
4718 /**
4719  * @}
4720  */
4721 
4722 /**
4723  * @addtogroup lavc_decoding
4724  * @{
4725  */
4726 
4727 /**
4728  * Find a registered decoder with a matching codec ID.
4729  *
4730  * @param id AVCodecID of the requested decoder
4731  * @return A decoder if one was found, NULL otherwise.
4732  */
4734 
4735 /**
4736  * Find a registered decoder with the specified name.
4737  *
4738  * @param name name of the requested decoder
4739  * @return A decoder if one was found, NULL otherwise.
4740  */
4742 
4743 /**
4744  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4745  * it can be called by custom get_buffer2() implementations for decoders without
4746  * AV_CODEC_CAP_DR1 set.
4747  */
4749 
4750 #if FF_API_EMU_EDGE
4751 /**
4752  * Return the amount of padding in pixels which the get_buffer callback must
4753  * provide around the edge of the image for codecs which do not have the
4754  * CODEC_FLAG_EMU_EDGE flag.
4755  *
4756  * @return Required padding in pixels.
4757  *
4758  * @deprecated CODEC_FLAG_EMU_EDGE is deprecated, so this function is no longer
4759  * needed
4760  */
4762 unsigned avcodec_get_edge_width(void);
4763 #endif
4764 
4765 /**
4766  * Modify width and height values so that they will result in a memory
4767  * buffer that is acceptable for the codec if you do not use any horizontal
4768  * padding.
4769  *
4770  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4771  */
4773 
4774 /**
4775  * Modify width and height values so that they will result in a memory
4776  * buffer that is acceptable for the codec if you also ensure that all
4777  * line sizes are a multiple of the respective linesize_align[i].
4778  *
4779  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4780  */
4782  int linesize_align[AV_NUM_DATA_POINTERS]);
4783 
4784 /**
4785  * Converts AVChromaLocation to swscale x/y chroma position.
4786  *
4787  * The positions represent the chroma (0,0) position in a coordinates system
4788  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4789  *
4790  * @param xpos horizontal chroma sample position
4791  * @param ypos vertical chroma sample position
4792  */
4793 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4794 
4795 /**
4796  * Converts swscale x/y chroma position to AVChromaLocation.
4797  *
4798  * The positions represent the chroma (0,0) position in a coordinates system
4799  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4800  *
4801  * @param xpos horizontal chroma sample position
4802  * @param ypos vertical chroma sample position
4803  */
4804 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4805 
4806 /**
4807  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4808  *
4809  * Some decoders may support multiple frames in a single AVPacket. Such
4810  * decoders would then just decode the first frame and the return value would be
4811  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4812  * called again with an AVPacket containing the remaining data in order to
4813  * decode the second frame, etc... Even if no frames are returned, the packet
4814  * needs to be fed to the decoder with remaining data until it is completely
4815  * consumed or an error occurs.
4816  *
4817  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4818  * and output. This means that for some packets they will not immediately
4819  * produce decoded output and need to be flushed at the end of decoding to get
4820  * all the decoded data. Flushing is done by calling this function with packets
4821  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4822  * returning samples. It is safe to flush even those decoders that are not
4823  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4824  *
4825  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4826  * larger than the actual read bytes because some optimized bitstream
4827  * readers read 32 or 64 bits at once and could read over the end.
4828  *
4829  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4830  * before packets may be fed to the decoder.
4831  *
4832  * @param avctx the codec context
4833  * @param[out] frame The AVFrame in which to store decoded audio samples.
4834  * The decoder will allocate a buffer for the decoded frame by
4835  * calling the AVCodecContext.get_buffer2() callback.
4836  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4837  * reference counted and the returned reference belongs to the
4838  * caller. The caller must release the frame using av_frame_unref()
4839  * when the frame is no longer needed. The caller may safely write
4840  * to the frame if av_frame_is_writable() returns 1.
4841  * When AVCodecContext.refcounted_frames is set to 0, the returned
4842  * reference belongs to the decoder and is valid only until the
4843  * next call to this function or until closing or flushing the
4844  * decoder. The caller may not write to it.
4845  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4846  * non-zero. Note that this field being set to zero
4847  * does not mean that an error has occurred. For
4848  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4849  * call is guaranteed to produce a frame.
4850  * @param[in] avpkt The input AVPacket containing the input buffer.
4851  * At least avpkt->data and avpkt->size should be set. Some
4852  * decoders might also require additional fields to be set.
4853  * @return A negative error code is returned if an error occurred during
4854  * decoding, otherwise the number of bytes consumed from the input
4855  * AVPacket is returned.
4856  *
4857 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4858  */
4861  int *got_frame_ptr, const AVPacket *avpkt);
4862 
4863 /**
4864  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4865  * Some decoders may support multiple frames in a single AVPacket, such
4866  * decoders would then just decode the first frame.
4867  *
4868  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4869  * the actual read bytes because some optimized bitstream readers read 32 or 64
4870  * bits at once and could read over the end.
4871  *
4872  * @warning The end of the input buffer buf should be set to 0 to ensure that
4873  * no overreading happens for damaged MPEG streams.
4874  *
4875  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4876  * between input and output, these need to be fed with avpkt->data=NULL,
4877  * avpkt->size=0 at the end to return the remaining frames.
4878  *
4879  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4880  * before packets may be fed to the decoder.
4881  *
4882  * @param avctx the codec context
4883  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4884  * Use av_frame_alloc() to get an AVFrame. The codec will
4885  * allocate memory for the actual bitmap by calling the
4886  * AVCodecContext.get_buffer2() callback.
4887  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4888  * reference counted and the returned reference belongs to the
4889  * caller. The caller must release the frame using av_frame_unref()
4890  * when the frame is no longer needed. The caller may safely write
4891  * to the frame if av_frame_is_writable() returns 1.
4892  * When AVCodecContext.refcounted_frames is set to 0, the returned
4893  * reference belongs to the decoder and is valid only until the
4894  * next call to this function or until closing or flushing the
4895  * decoder. The caller may not write to it.
4896  *
4897  * @param[in] avpkt The input AVPacket containing the input buffer.
4898  * You can create such packet with av_init_packet() and by then setting
4899  * data and size, some decoders might in addition need other fields like
4900  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4901  * fields possible.
4902  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4903  * @return On error a negative value is returned, otherwise the number of bytes
4904  * used or zero if no frame could be decompressed.
4905  *
4906  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4907  */
4909 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4910  int *got_picture_ptr,
4911  const AVPacket *avpkt);
4912 
4913 /**
4914  * Decode a subtitle message.
4915  * Return a negative value on error, otherwise return the number of bytes used.
4916  * If no subtitle could be decompressed, got_sub_ptr is zero.
4917  * Otherwise, the subtitle is stored in *sub.
4918  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4919  * simplicity, because the performance difference is expect to be negligible
4920  * and reusing a get_buffer written for video codecs would probably perform badly
4921  * due to a potentially very different allocation pattern.
4922  *
4923  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4924  * and output. This means that for some packets they will not immediately
4925  * produce decoded output and need to be flushed at the end of decoding to get
4926  * all the decoded data. Flushing is done by calling this function with packets
4927  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4928  * returning subtitles. It is safe to flush even those decoders that are not
4929  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4930  *
4931  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4932  * before packets may be fed to the decoder.
4933  *
4934  * @param avctx the codec context
4935  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4936  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4937  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4938  * @param[in] avpkt The input AVPacket containing the input buffer.
4939  */
4941  int *got_sub_ptr,
4942  AVPacket *avpkt);
4943 
4944 /**
4945  * Supply raw packet data as input to a decoder.
4946  *
4947  * Internally, this call will copy relevant AVCodecContext fields, which can
4948  * influence decoding per-packet, and apply them when the packet is actually
4949  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4950  * decoder to drop the frame contained by the packet sent with this function.)
4951  *
4952  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4953  * larger than the actual read bytes because some optimized bitstream
4954  * readers read 32 or 64 bits at once and could read over the end.
4955  *
4956  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4957  * on the same AVCodecContext. It will return unexpected results now
4958  * or in future libavcodec versions.
4959  *
4960  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4961  * before packets may be fed to the decoder.
4962  *
4963  * @param avctx codec context
4964  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4965  * frame, or several complete audio frames.
4966  * Ownership of the packet remains with the caller, and the
4967  * decoder will not write to the packet. The decoder may create
4968  * a reference to the packet data (or copy it if the packet is
4969  * not reference-counted).
4970  * Unlike with older APIs, the packet is always fully consumed,
4971  * and if it contains multiple frames (e.g. some audio codecs),
4972  * will require you to call avcodec_receive_frame() multiple
4973  * times afterwards before you can send a new packet.
4974  * It can be NULL (or an AVPacket with data set to NULL and
4975  * size set to 0); in this case, it is considered a flush
4976  * packet, which signals the end of the stream. Sending the
4977  * first flush packet will return success. Subsequent ones are
4978  * unnecessary and will return AVERROR_EOF. If the decoder
4979  * still has frames buffered, it will return them after sending
4980  * a flush packet.
4981  *
4982  * @return 0 on success, otherwise negative error code:
4983  * AVERROR(EAGAIN): input is not accepted in the current state - user
4984  * must read output with avcodec_receive_frame() (once
4985  * all output is read, the packet should be resent, and
4986  * the call will not fail with EAGAIN).
4987  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4988  * be sent to it (also returned if more than 1 flush
4989  * packet is sent)
4990  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4991  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4992  * other errors: legitimate decoding errors
4993  */
4994 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4995 
4996 /**
4997  * Return decoded output data from a decoder.
4998  *
4999  * @param avctx codec context
5000  * @param frame This will be set to a reference-counted video or audio
5001  * frame (depending on the decoder type) allocated by the
5002  * decoder. Note that the function will always call
5003  * av_frame_unref(frame) before doing anything else.
5004  *
5005  * @return
5006  * 0: success, a frame was returned
5007  * AVERROR(EAGAIN): output is not available in this state - user must try
5008  * to send new input
5009  * AVERROR_EOF: the decoder has been fully flushed, and there will be
5010  * no more output frames
5011  * AVERROR(EINVAL): codec not opened, or it is an encoder
5012  * other negative values: legitimate decoding errors
5013  */
5015 
5016 /**
5017  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
5018  * to retrieve buffered output packets.
5019  *
5020  * @param avctx codec context
5021  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
5022  * Ownership of the frame remains with the caller, and the
5023  * encoder will not write to the frame. The encoder may create
5024  * a reference to the frame data (or copy it if the frame is
5025  * not reference-counted).
5026  * It can be NULL, in which case it is considered a flush
5027  * packet. This signals the end of the stream. If the encoder
5028  * still has packets buffered, it will return them after this
5029  * call. Once flushing mode has been entered, additional flush
5030  * packets are ignored, and sending frames will return
5031  * AVERROR_EOF.
5032  *
5033  * For audio:
5034  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5035  * can have any number of samples.
5036  * If it is not set, frame->nb_samples must be equal to
5037  * avctx->frame_size for all frames except the last.
5038  * The final frame may be smaller than avctx->frame_size.
5039  * @return 0 on success, otherwise negative error code:
5040  * AVERROR(EAGAIN): input is not accepted in the current state - user
5041  * must read output with avcodec_receive_packet() (once
5042  * all output is read, the packet should be resent, and
5043  * the call will not fail with EAGAIN).
5044  * AVERROR_EOF: the encoder has been flushed, and no new frames can
5045  * be sent to it
5046  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
5047  * decoder, or requires flush
5048  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
5049  * other errors: legitimate decoding errors
5050  */
5051 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
5052 
5053 /**
5054  * Read encoded data from the encoder.
5055  *
5056  * @param avctx codec context
5057  * @param avpkt This will be set to a reference-counted packet allocated by the
5058  * encoder. Note that the function will always call
5059  * av_frame_unref(frame) before doing anything else.
5060  * @return 0 on success, otherwise negative error code:
5061  * AVERROR(EAGAIN): output is not available in the current state - user
5062  * must try to send input
5063  * AVERROR_EOF: the encoder has been fully flushed, and there will be
5064  * no more output packets
5065  * AVERROR(EINVAL): codec not opened, or it is an encoder
5066  * other errors: legitimate decoding errors
5067  */
5068 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
5069 
5070 
5071 /**
5072  * @defgroup lavc_parsing Frame parsing
5073  * @{
5074  */
5075 
5078  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5079  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5080  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5081 };
5082 
5083 typedef struct AVCodecParserContext {
5084  void *priv_data;
5086  int64_t frame_offset; /* offset of the current frame */
5087  int64_t cur_offset; /* current offset
5088  (incremented by each av_parser_parse()) */
5089  int64_t next_frame_offset; /* offset of the next frame */
5090  /* video info */
5091  int pict_type; /* XXX: Put it back in AVCodecContext. */
5092  /**
5093  * This field is used for proper frame duration computation in lavf.
5094  * It signals, how much longer the frame duration of the current frame
5095  * is compared to normal frame duration.
5096  *
5097  * frame_duration = (1 + repeat_pict) * time_base
5098  *
5099  * It is used by codecs like H.264 to display telecined material.
5100  */
5101  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5102  int64_t pts; /* pts of the current frame */
5103  int64_t dts; /* dts of the current frame */
5104 
5105  /* private data */
5106  int64_t last_pts;
5107  int64_t last_dts;
5109 
5110 #define AV_PARSER_PTS_NB 4
5115 
5116  int flags;
5117 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5118 #define PARSER_FLAG_ONCE 0x0002
5119 /// Set if the parser has a valid file offset
5120 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5121 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5122 
5123  int64_t offset; ///< byte offset from starting packet start
5125 
5126  /**
5127  * Set by parser to 1 for key frames and 0 for non-key frames.
5128  * It is initialized to -1, so if the parser doesn't set this flag,
5129  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5130  * will be used.
5131  */
5133 
5134 #if FF_API_CONVERGENCE_DURATION
5135  /**
5136  * @deprecated unused
5137  */
5140 #endif
5141 
5142  // Timestamp generation support:
5143  /**
5144  * Synchronization point for start of timestamp generation.
5145  *
5146  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5147  * (default).
5148  *
5149  * For example, this corresponds to presence of H.264 buffering period
5150  * SEI message.
5151  */
5153 
5154  /**
5155  * Offset of the current timestamp against last timestamp sync point in
5156  * units of AVCodecContext.time_base.
5157  *
5158  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5159  * contain a valid timestamp offset.
5160  *
5161  * Note that the timestamp of sync point has usually a nonzero
5162  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5163  * the next frame after timestamp sync point will be usually 1.
5164  *
5165  * For example, this corresponds to H.264 cpb_removal_delay.
5166  */
5168 
5169  /**
5170  * Presentation delay of current frame in units of AVCodecContext.time_base.
5171  *
5172  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5173  * contain valid non-negative timestamp delta (presentation time of a frame
5174  * must not lie in the past).
5175  *
5176  * This delay represents the difference between decoding and presentation
5177  * time of the frame.
5178  *
5179  * For example, this corresponds to H.264 dpb_output_delay.
5180  */
5182 
5183  /**
5184  * Position of the packet in file.
5185  *
5186  * Analogous to cur_frame_pts/dts
5187  */
5189 
5190  /**
5191  * Byte position of currently parsed frame in stream.
5192  */
5193  int64_t pos;
5194 
5195  /**
5196  * Previous frame byte position.
5197  */
5198  int64_t last_pos;
5199 
5200  /**
5201  * Duration of the current frame.
5202  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5203  * For all other types, this is in units of AVCodecContext.time_base.
5204  */
5206 
5208 
5209  /**
5210  * Indicate whether a picture is coded as a frame, top field or bottom field.
5211  *
5212  * For example, H.264 field_pic_flag equal to 0 corresponds to
5213  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5214  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5215  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5216  */
5218 
5219  /**
5220  * Picture number incremented in presentation or output order.
5221  * This field may be reinitialized at the first picture of a new sequence.
5222  *
5223  * For example, this corresponds to H.264 PicOrderCnt.
5224  */
5226 
5227  /**
5228  * Dimensions of the decoded video intended for presentation.
5229  */
5230  int width;
5231  int height;
5232 
5233  /**
5234  * Dimensions of the coded video.
5235  */
5238 
5239  /**
5240  * The format of the coded data, corresponds to enum AVPixelFormat for video
5241  * and for enum AVSampleFormat for audio.
5242  *
5243  * Note that a decoder can have considerable freedom in how exactly it
5244  * decodes the data, so the format reported here might be different from the
5245  * one returned by a decoder.
5246  */
5247  int format;
5249 
5250 typedef struct AVCodecParser {
5251  int codec_ids[5]; /* several codec IDs are permitted */
5254  /* This callback never returns an error, a negative value means that
5255  * the frame start was in a previous packet. */
5257  AVCodecContext *avctx,
5258  const uint8_t **poutbuf, int *poutbuf_size,
5259  const uint8_t *buf, int buf_size);
5261  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5263 } AVCodecParser;
5264 
5266 
5269 
5270 /**
5271  * Parse a packet.
5272  *
5273  * @param s parser context.
5274  * @param avctx codec context.
5275  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5276  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5277  * @param buf input buffer.
5278  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5279  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5280  To signal EOF, this should be 0 (so that the last frame
5281  can be output).
5282  * @param pts input presentation timestamp.
5283  * @param dts input decoding timestamp.
5284  * @param pos input byte position in stream.
5285  * @return the number of bytes of the input bitstream used.
5286  *
5287  * Example:
5288  * @code
5289  * while(in_len){
5290  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5291  * in_data, in_len,
5292  * pts, dts, pos);
5293  * in_data += len;
5294  * in_len -= len;
5295  *
5296  * if(size)
5297  * decode_frame(data, size);
5298  * }
5299  * @endcode
5300  */
5302  AVCodecContext *avctx,
5303  uint8_t **poutbuf, int *poutbuf_size,
5304  const uint8_t *