FFmpeg
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/hwcontext.h"
40 #include "libavutil/log.h"
41 #include "libavutil/pixfmt.h"
42 #include "libavutil/rational.h"
43 
44 #include "version.h"
45 
46 /**
47  * @defgroup libavc libavcodec
48  * Encoding/Decoding Library
49  *
50  * @{
51  *
52  * @defgroup lavc_decoding Decoding
53  * @{
54  * @}
55  *
56  * @defgroup lavc_encoding Encoding
57  * @{
58  * @}
59  *
60  * @defgroup lavc_codec Codecs
61  * @{
62  * @defgroup lavc_codec_native Native Codecs
63  * @{
64  * @}
65  * @defgroup lavc_codec_wrappers External library wrappers
66  * @{
67  * @}
68  * @defgroup lavc_codec_hwaccel Hardware Accelerators bridge
69  * @{
70  * @}
71  * @}
72  * @defgroup lavc_internal Internal
73  * @{
74  * @}
75  * @}
76  */
77 
78 /**
79  * @ingroup libavc
80  * @defgroup lavc_encdec send/receive encoding and decoding API overview
81  * @{
82  *
83  * The avcodec_send_packet()/avcodec_receive_frame()/avcodec_send_frame()/
84  * avcodec_receive_packet() functions provide an encode/decode API, which
85  * decouples input and output.
86  *
87  * The API is very similar for encoding/decoding and audio/video, and works as
88  * follows:
89  * - Set up and open the AVCodecContext as usual.
90  * - Send valid input:
91  * - For decoding, call avcodec_send_packet() to give the decoder raw
92  * compressed data in an AVPacket.
93  * - For encoding, call avcodec_send_frame() to give the encoder an AVFrame
94  * containing uncompressed audio or video.
95  * In both cases, it is recommended that AVPackets and AVFrames are
96  * refcounted, or libavcodec might have to copy the input data. (libavformat
97  * always returns refcounted AVPackets, and av_frame_get_buffer() allocates
98  * refcounted AVFrames.)
99  * - Receive output in a loop. Periodically call one of the avcodec_receive_*()
100  * functions and process their output:
101  * - For decoding, call avcodec_receive_frame(). On success, it will return
102  * an AVFrame containing uncompressed audio or video data.
103  * - For encoding, call avcodec_receive_packet(). On success, it will return
104  * an AVPacket with a compressed frame.
105  * Repeat this call until it returns AVERROR(EAGAIN) or an error. The
106  * AVERROR(EAGAIN) return value means that new input data is required to
107  * return new output. In this case, continue with sending input. For each
108  * input frame/packet, the codec will typically return 1 output frame/packet,
109  * but it can also be 0 or more than 1.
110  *
111  * At the beginning of decoding or encoding, the codec might accept multiple
112  * input frames/packets without returning a frame, until its internal buffers
113  * are filled. This situation is handled transparently if you follow the steps
114  * outlined above.
115  *
116  * In theory, sending input can result in EAGAIN - this should happen only if
117  * not all output was received. You can use this to structure alternative decode
118  * or encode loops other than the one suggested above. For example, you could
119  * try sending new input on each iteration, and try to receive output if that
120  * returns EAGAIN.
121  *
122  * End of stream situations. These require "flushing" (aka draining) the codec,
123  * as the codec might buffer multiple frames or packets internally for
124  * performance or out of necessity (consider B-frames).
125  * This is handled as follows:
126  * - Instead of valid input, send NULL to the avcodec_send_packet() (decoding)
127  * or avcodec_send_frame() (encoding) functions. This will enter draining
128  * mode.
129  * - Call avcodec_receive_frame() (decoding) or avcodec_receive_packet()
130  * (encoding) in a loop until AVERROR_EOF is returned. The functions will
131  * not return AVERROR(EAGAIN), unless you forgot to enter draining mode.
132  * - Before decoding can be resumed again, the codec has to be reset with
133  * avcodec_flush_buffers().
134  *
135  * Using the API as outlined above is highly recommended. But it is also
136  * possible to call functions outside of this rigid schema. For example, you can
137  * call avcodec_send_packet() repeatedly without calling
138  * avcodec_receive_frame(). In this case, avcodec_send_packet() will succeed
139  * until the codec's internal buffer has been filled up (which is typically of
140  * size 1 per output frame, after initial input), and then reject input with
141  * AVERROR(EAGAIN). Once it starts rejecting input, you have no choice but to
142  * read at least some output.
143  *
144  * Not all codecs will follow a rigid and predictable dataflow; the only
145  * guarantee is that an AVERROR(EAGAIN) return value on a send/receive call on
146  * one end implies that a receive/send call on the other end will succeed, or
147  * at least will not fail with AVERROR(EAGAIN). In general, no codec will
148  * permit unlimited buffering of input or output.
149  *
150  * This API replaces the following legacy functions:
151  * - avcodec_decode_video2() and avcodec_decode_audio4():
152  * Use avcodec_send_packet() to feed input to the decoder, then use
153  * avcodec_receive_frame() to receive decoded frames after each packet.
154  * Unlike with the old video decoding API, multiple frames might result from
155  * a packet. For audio, splitting the input packet into frames by partially
156  * decoding packets becomes transparent to the API user. You never need to
157  * feed an AVPacket to the API twice (unless it is rejected with AVERROR(EAGAIN) - then
158  * no data was read from the packet).
159  * Additionally, sending a flush/draining packet is required only once.
160  * - avcodec_encode_video2()/avcodec_encode_audio2():
161  * Use avcodec_send_frame() to feed input to the encoder, then use
162  * avcodec_receive_packet() to receive encoded packets.
163  * Providing user-allocated buffers for avcodec_receive_packet() is not
164  * possible.
165  * - The new API does not handle subtitles yet.
166  *
167  * Mixing new and old function calls on the same AVCodecContext is not allowed,
168  * and will result in undefined behavior.
169  *
170  * Some codecs might require using the new API; using the old API will return
171  * an error when calling it. All codecs support the new API.
172  *
173  * A codec is not allowed to return AVERROR(EAGAIN) for both sending and receiving. This
174  * would be an invalid state, which could put the codec user into an endless
175  * loop. The API has no concept of time either: it cannot happen that trying to
176  * do avcodec_send_packet() results in AVERROR(EAGAIN), but a repeated call 1 second
177  * later accepts the packet (with no other receive/flush API calls involved).
178  * The API is a strict state machine, and the passage of time is not supposed
179  * to influence it. Some timing-dependent behavior might still be deemed
180  * acceptable in certain cases. But it must never result in both send/receive
181  * returning EAGAIN at the same time at any point. It must also absolutely be
182  * avoided that the current state is "unstable" and can "flip-flop" between
183  * the send/receive APIs allowing progress. For example, it's not allowed that
184  * the codec randomly decides that it actually wants to consume a packet now
185  * instead of returning a frame, after it just returned AVERROR(EAGAIN) on an
186  * avcodec_send_packet() call.
187  * @}
188  */
189 
190 /**
191  * @defgroup lavc_core Core functions/structures.
192  * @ingroup libavc
193  *
194  * Basic definitions, functions for querying libavcodec capabilities,
195  * allocating core structures, etc.
196  * @{
197  */
198 
199 
200 /**
201  * Identify the syntax and semantics of the bitstream.
202  * The principle is roughly:
203  * Two decoders with the same ID can decode the same streams.
204  * Two encoders with the same ID can encode compatible streams.
205  * There may be slight deviations from the principle due to implementation
206  * details.
207  *
208  * If you add a codec ID to this list, add it so that
209  * 1. no value of an existing codec ID changes (that would break ABI),
210  * 2. it is as close as possible to similar codecs
211  *
212  * After adding new codec IDs, do not forget to add an entry to the codec
213  * descriptor list and bump libavcodec minor version.
214  */
215 enum AVCodecID {
217 
218  /* video codecs */
220  AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
355 #define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
393 #define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
413 
461 
462  /* various PCM "codecs" */
463  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
495 
501 
502  /* various ADPCM codecs */
534 
546 
547  /* AMR */
550 
551  /* RealAudio codecs*/
554 
555  /* various DPCM codecs */
560 
563 
564  /* audio codecs */
565  AV_CODEC_ID_MP2 = 0x15000,
566  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
583  AV_CODEC_ID_GSM, ///< as in Berlin toast format
595  AV_CODEC_ID_GSM_MS, /* as found in WAV */
633 
657 
658  /* subtitle codecs */
659  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
662  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
669 
687 
688  /* other specific kind of codecs (generally used for attachments) */
689  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
690  AV_CODEC_ID_TTF = 0x18000,
691 
692  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
702 
703 
704  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
705 
706  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
707  * stream (only used by libavformat) */
708  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
709  * stream (only used by libavformat) */
710  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
711  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
712 };
713 
714 /**
715  * This struct describes the properties of a single codec described by an
716  * AVCodecID.
717  * @see avcodec_descriptor_get()
718  */
719 typedef struct AVCodecDescriptor {
720  enum AVCodecID id;
722  /**
723  * Name of the codec described by this descriptor. It is non-empty and
724  * unique for each codec descriptor. It should contain alphanumeric
725  * characters and '_' only.
726  */
727  const char *name;
728  /**
729  * A more descriptive name for this codec. May be NULL.
730  */
731  const char *long_name;
732  /**
733  * Codec properties, a combination of AV_CODEC_PROP_* flags.
734  */
735  int props;
736  /**
737  * MIME type(s) associated with the codec.
738  * May be NULL; if not, a NULL-terminated array of MIME types.
739  * The first item is always non-NULL and is the preferred MIME type.
740  */
741  const char *const *mime_types;
742  /**
743  * If non-NULL, an array of profiles recognized for this codec.
744  * Terminated with FF_PROFILE_UNKNOWN.
745  */
746  const struct AVProfile *profiles;
748 
749 /**
750  * Codec uses only intra compression.
751  * Video and audio codecs only.
752  */
753 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
754 /**
755  * Codec supports lossy compression. Audio and video codecs only.
756  * @note a codec may support both lossy and lossless
757  * compression modes
758  */
759 #define AV_CODEC_PROP_LOSSY (1 << 1)
760 /**
761  * Codec supports lossless compression. Audio and video codecs only.
762  */
763 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
764 /**
765  * Codec supports frame reordering. That is, the coded order (the order in which
766  * the encoded packets are output by the encoders / stored / input to the
767  * decoders) may be different from the presentation order of the corresponding
768  * frames.
769  *
770  * For codecs that do not have this property set, PTS and DTS should always be
771  * equal.
772  */
773 #define AV_CODEC_PROP_REORDER (1 << 3)
774 /**
775  * Subtitle codec is bitmap based
776  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
777  */
778 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
779 /**
780  * Subtitle codec is text based.
781  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
782  */
783 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
784 
785 /**
786  * @ingroup lavc_decoding
787  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
788  * This is mainly needed because some optimized bitstream readers read
789  * 32 or 64 bit at once and could read over the end.<br>
790  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
791  * MPEG bitstreams could cause overread and segfault.
792  */
793 #define AV_INPUT_BUFFER_PADDING_SIZE 64
794 
795 /**
796  * @ingroup lavc_encoding
797  * minimum encoding buffer size
798  * Used to avoid some checks during header writing.
799  */
800 #define AV_INPUT_BUFFER_MIN_SIZE 16384
801 
802 /**
803  * @ingroup lavc_decoding
804  */
806  /* We leave some space between them for extensions (drop some
807  * keyframes for intra-only or drop just some bidir frames). */
808  AVDISCARD_NONE =-16, ///< discard nothing
809  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
810  AVDISCARD_NONREF = 8, ///< discard all non reference
811  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
812  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
813  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
814  AVDISCARD_ALL = 48, ///< discard all
815 };
816 
827  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
828 };
829 
830 /**
831  * @ingroup lavc_encoding
832  */
833 typedef struct RcOverride{
836  int qscale; // If this is 0 then quality_factor will be used instead.
838 } RcOverride;
839 
840 /* encoding support
841  These flags can be passed in AVCodecContext.flags before initialization.
842  Note: Not everything is supported yet.
843 */
844 
845 /**
846  * Allow decoders to produce frames with data planes that are not aligned
847  * to CPU requirements (e.g. due to cropping).
848  */
849 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
850 /**
851  * Use fixed qscale.
852  */
853 #define AV_CODEC_FLAG_QSCALE (1 << 1)
854 /**
855  * 4 MV per MB allowed / advanced prediction for H.263.
856  */
857 #define AV_CODEC_FLAG_4MV (1 << 2)
858 /**
859  * Output even those frames that might be corrupted.
860  */
861 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
862 /**
863  * Use qpel MC.
864  */
865 #define AV_CODEC_FLAG_QPEL (1 << 4)
866 /**
867  * Don't output frames whose parameters differ from first
868  * decoded frame in stream.
869  */
870 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
871 /**
872  * Use internal 2pass ratecontrol in first pass mode.
873  */
874 #define AV_CODEC_FLAG_PASS1 (1 << 9)
875 /**
876  * Use internal 2pass ratecontrol in second pass mode.
877  */
878 #define AV_CODEC_FLAG_PASS2 (1 << 10)
879 /**
880  * loop filter.
881  */
882 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
883 /**
884  * Only decode/encode grayscale.
885  */
886 #define AV_CODEC_FLAG_GRAY (1 << 13)
887 /**
888  * error[?] variables will be set during encoding.
889  */
890 #define AV_CODEC_FLAG_PSNR (1 << 15)
891 /**
892  * Input bitstream might be truncated at a random location
893  * instead of only at frame boundaries.
894  */
895 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
896 /**
897  * Use interlaced DCT.
898  */
899 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
900 /**
901  * Force low delay.
902  */
903 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
904 /**
905  * Place global headers in extradata instead of every keyframe.
906  */
907 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
908 /**
909  * Use only bitexact stuff (except (I)DCT).
910  */
911 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
912 /* Fx : Flag for H.263+ extra options */
913 /**
914  * H.263 advanced intra coding / MPEG-4 AC prediction
915  */
916 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
917 /**
918  * interlaced motion estimation
919  */
920 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
921 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
922 
923 /**
924  * Allow non spec compliant speedup tricks.
925  */
926 #define AV_CODEC_FLAG2_FAST (1 << 0)
927 /**
928  * Skip bitstream encoding.
929  */
930 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
931 /**
932  * Place global headers at every keyframe instead of in extradata.
933  */
934 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
935 
936 /**
937  * timecode is in drop frame format. DEPRECATED!!!!
938  */
939 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
940 
941 /**
942  * Input bitstream might be truncated at a packet boundaries
943  * instead of only at frame boundaries.
944  */
945 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
946 /**
947  * Discard cropping information from SPS.
948  */
949 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
950 
951 /**
952  * Show all frames before the first keyframe
953  */
954 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
955 /**
956  * Export motion vectors through frame side data
957  */
958 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
959 /**
960  * Do not skip samples and export skip information as frame side data
961  */
962 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
963 /**
964  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
965  */
966 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
967 
968 /* Unsupported options :
969  * Syntax Arithmetic coding (SAC)
970  * Reference Picture Selection
971  * Independent Segment Decoding */
972 /* /Fx */
973 /* codec capabilities */
974 
975 /**
976  * Decoder can use draw_horiz_band callback.
977  */
978 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
979 /**
980  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
981  * If not set, it might not use get_buffer() at all or use operations that
982  * assume the buffer was allocated by avcodec_default_get_buffer.
983  */
984 #define AV_CODEC_CAP_DR1 (1 << 1)
985 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
986 /**
987  * Encoder or decoder requires flushing with NULL input at the end in order to
988  * give the complete and correct output.
989  *
990  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
991  * with NULL data. The user can still send NULL data to the public encode
992  * or decode function, but libavcodec will not pass it along to the codec
993  * unless this flag is set.
994  *
995  * Decoders:
996  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
997  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
998  * returns frames.
999  *
1000  * Encoders:
1001  * The encoder needs to be fed with NULL data at the end of encoding until the
1002  * encoder no longer returns data.
1003  *
1004  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1005  * flag also means that the encoder must set the pts and duration for
1006  * each output packet. If this flag is not set, the pts and duration will
1007  * be determined by libavcodec from the input frame.
1008  */
1009 #define AV_CODEC_CAP_DELAY (1 << 5)
1010 /**
1011  * Codec can be fed a final frame with a smaller size.
1012  * This can be used to prevent truncation of the last audio samples.
1013  */
1014 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
1015 
1016 /**
1017  * Codec can output multiple frames per AVPacket
1018  * Normally demuxers return one frame at a time, demuxers which do not do
1019  * are connected to a parser to split what they return into proper frames.
1020  * This flag is reserved to the very rare category of codecs which have a
1021  * bitstream that cannot be split into frames without timeconsuming
1022  * operations like full decoding. Demuxers carrying such bitstreams thus
1023  * may return multiple frames in a packet. This has many disadvantages like
1024  * prohibiting stream copy in many cases thus it should only be considered
1025  * as a last resort.
1026  */
1027 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1028 /**
1029  * Codec is experimental and is thus avoided in favor of non experimental
1030  * encoders
1031  */
1032 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1033 /**
1034  * Codec should fill in channel configuration and samplerate instead of container
1035  */
1036 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1037 /**
1038  * Codec supports frame-level multithreading.
1039  */
1040 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1041 /**
1042  * Codec supports slice-based (or partition-based) multithreading.
1043  */
1044 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1045 /**
1046  * Codec supports changed parameters at any point.
1047  */
1048 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1049 /**
1050  * Codec supports avctx->thread_count == 0 (auto).
1051  */
1052 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1053 /**
1054  * Audio encoder supports receiving a different number of samples in each call.
1055  */
1056 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1057 /**
1058  * Decoder is not a preferred choice for probing.
1059  * This indicates that the decoder is not a good choice for probing.
1060  * It could for example be an expensive to spin up hardware decoder,
1061  * or it could simply not provide a lot of useful information about
1062  * the stream.
1063  * A decoder marked with this flag should only be used as last resort
1064  * choice for probing.
1065  */
1066 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1067 /**
1068  * Codec is intra only.
1069  */
1070 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1071 /**
1072  * Codec is lossless.
1073  */
1074 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1075 
1076 /**
1077  * Codec is backed by a hardware implementation. Typically used to
1078  * identify a non-hwaccel hardware decoder. For information about hwaccels, use
1079  * avcodec_get_hw_config() instead.
1080  */
1081 #define AV_CODEC_CAP_HARDWARE (1 << 18)
1082 
1083 /**
1084  * Codec is potentially backed by a hardware implementation, but not
1085  * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
1086  * implementation provides some sort of internal fallback.
1087  */
1088 #define AV_CODEC_CAP_HYBRID (1 << 19)
1089 
1090 /**
1091  * This codec takes the reordered_opaque field from input AVFrames
1092  * and returns it in the corresponding field in AVCodecContext after
1093  * encoding.
1094  */
1095 #define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
1096 
1097 /**
1098  * Pan Scan area.
1099  * This specifies the area which should be displayed.
1100  * Note there may be multiple such areas for one frame.
1101  */
1102 typedef struct AVPanScan {
1103  /**
1104  * id
1105  * - encoding: Set by user.
1106  * - decoding: Set by libavcodec.
1107  */
1108  int id;
1109 
1110  /**
1111  * width and height in 1/16 pel
1112  * - encoding: Set by user.
1113  * - decoding: Set by libavcodec.
1114  */
1115  int width;
1116  int height;
1117 
1118  /**
1119  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1120  * - encoding: Set by user.
1121  * - decoding: Set by libavcodec.
1122  */
1123  int16_t position[3][2];
1124 } AVPanScan;
1125 
1126 /**
1127  * This structure describes the bitrate properties of an encoded bitstream. It
1128  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1129  * parameters for H.264/HEVC.
1130  */
1131 typedef struct AVCPBProperties {
1132  /**
1133  * Maximum bitrate of the stream, in bits per second.
1134  * Zero if unknown or unspecified.
1135  */
1136 #if FF_API_UNSANITIZED_BITRATES
1138 #else
1139  int64_t max_bitrate;
1140 #endif
1141  /**
1142  * Minimum bitrate of the stream, in bits per second.
1143  * Zero if unknown or unspecified.
1144  */
1145 #if FF_API_UNSANITIZED_BITRATES
1147 #else
1148  int64_t min_bitrate;
1149 #endif
1150  /**
1151  * Average bitrate of the stream, in bits per second.
1152  * Zero if unknown or unspecified.
1153  */
1154 #if FF_API_UNSANITIZED_BITRATES
1156 #else
1157  int64_t avg_bitrate;
1158 #endif
1159 
1160  /**
1161  * The size of the buffer to which the ratecontrol is applied, in bits.
1162  * Zero if unknown or unspecified.
1163  */
1165 
1166  /**
1167  * The delay between the time the packet this structure is associated with
1168  * is received and the time when it should be decoded, in periods of a 27MHz
1169  * clock.
1170  *
1171  * UINT64_MAX when unknown or unspecified.
1172  */
1173  uint64_t vbv_delay;
1174 } AVCPBProperties;
1175 
1176 /**
1177  * The decoder will keep a reference to the frame and may reuse it later.
1178  */
1179 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1180 
1181 /**
1182  * @defgroup lavc_packet AVPacket
1183  *
1184  * Types and functions for working with AVPacket.
1185  * @{
1186  */
1188  /**
1189  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1190  * bytes worth of palette. This side data signals that a new palette is
1191  * present.
1192  */
1194 
1195  /**
1196  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1197  * that the extradata buffer was changed and the receiving side should
1198  * act upon it appropriately. The new extradata is embedded in the side
1199  * data buffer and should be immediately used for processing the current
1200  * frame or packet.
1201  */
1203 
1204  /**
1205  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1206  * @code
1207  * u32le param_flags
1208  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1209  * s32le channel_count
1210  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1211  * u64le channel_layout
1212  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1213  * s32le sample_rate
1214  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1215  * s32le width
1216  * s32le height
1217  * @endcode
1218  */
1220 
1221  /**
1222  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1223  * structures with info about macroblocks relevant to splitting the
1224  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1225  * That is, it does not necessarily contain info about all macroblocks,
1226  * as long as the distance between macroblocks in the info is smaller
1227  * than the target payload size.
1228  * Each MB info structure is 12 bytes, and is laid out as follows:
1229  * @code
1230  * u32le bit offset from the start of the packet
1231  * u8 current quantizer at the start of the macroblock
1232  * u8 GOB number
1233  * u16le macroblock address within the GOB
1234  * u8 horizontal MV predictor
1235  * u8 vertical MV predictor
1236  * u8 horizontal MV predictor for block number 3
1237  * u8 vertical MV predictor for block number 3
1238  * @endcode
1239  */
1241 
1242  /**
1243  * This side data should be associated with an audio stream and contains
1244  * ReplayGain information in form of the AVReplayGain struct.
1245  */
1247 
1248  /**
1249  * This side data contains a 3x3 transformation matrix describing an affine
1250  * transformation that needs to be applied to the decoded video frames for
1251  * correct presentation.
1252  *
1253  * See libavutil/display.h for a detailed description of the data.
1254  */
1256 
1257  /**
1258  * This side data should be associated with a video stream and contains
1259  * Stereoscopic 3D information in form of the AVStereo3D struct.
1260  */
1262 
1263  /**
1264  * This side data should be associated with an audio stream and corresponds
1265  * to enum AVAudioServiceType.
1266  */
1268 
1269  /**
1270  * This side data contains quality related information from the encoder.
1271  * @code
1272  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1273  * u8 picture type
1274  * u8 error count
1275  * u16 reserved
1276  * u64le[error count] sum of squared differences between encoder in and output
1277  * @endcode
1278  */
1280 
1281  /**
1282  * This side data contains an integer value representing the stream index
1283  * of a "fallback" track. A fallback track indicates an alternate
1284  * track to use when the current track can not be decoded for some reason.
1285  * e.g. no decoder available for codec.
1286  */
1288 
1289  /**
1290  * This side data corresponds to the AVCPBProperties struct.
1291  */
1293 
1294  /**
1295  * Recommmends skipping the specified number of samples
1296  * @code
1297  * u32le number of samples to skip from start of this packet
1298  * u32le number of samples to skip from end of this packet
1299  * u8 reason for start skip
1300  * u8 reason for end skip (0=padding silence, 1=convergence)
1301  * @endcode
1302  */
1304 
1305  /**
1306  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1307  * the packet may contain "dual mono" audio specific to Japanese DTV
1308  * and if it is true, recommends only the selected channel to be used.
1309  * @code
1310  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1311  * @endcode
1312  */
1314 
1315  /**
1316  * A list of zero terminated key/value strings. There is no end marker for
1317  * the list, so it is required to rely on the side data size to stop.
1318  */
1320 
1321  /**
1322  * Subtitle event position
1323  * @code
1324  * u32le x1
1325  * u32le y1
1326  * u32le x2
1327  * u32le y2
1328  * @endcode
1329  */
1331 
1332  /**
1333  * Data found in BlockAdditional element of matroska container. There is
1334  * no end marker for the data, so it is required to rely on the side data
1335  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1336  * by data.
1337  */
1339 
1340  /**
1341  * The optional first identifier line of a WebVTT cue.
1342  */
1344 
1345  /**
1346  * The optional settings (rendering instructions) that immediately
1347  * follow the timestamp specifier of a WebVTT cue.
1348  */
1350 
1351  /**
1352  * A list of zero terminated key/value strings. There is no end marker for
1353  * the list, so it is required to rely on the side data size to stop. This
1354  * side data includes updated metadata which appeared in the stream.
1355  */
1357 
1358  /**
1359  * MPEGTS stream ID as uint8_t, this is required to pass the stream ID
1360  * information from the demuxer to the corresponding muxer.
1361  */
1363 
1364  /**
1365  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1366  * should be associated with a video stream and contains data in the form
1367  * of the AVMasteringDisplayMetadata struct.
1368  */
1370 
1371  /**
1372  * This side data should be associated with a video stream and corresponds
1373  * to the AVSphericalMapping structure.
1374  */
1376 
1377  /**
1378  * Content light level (based on CTA-861.3). This metadata should be
1379  * associated with a video stream and contains data in the form of the
1380  * AVContentLightMetadata struct.
1381  */
1383 
1384  /**
1385  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1386  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1387  * The number of bytes of CC data is AVPacketSideData.size.
1388  */
1390 
1391  /**
1392  * This side data is encryption initialization data.
1393  * The format is not part of ABI, use av_encryption_init_info_* methods to
1394  * access.
1395  */
1397 
1398  /**
1399  * This side data contains encryption info for how to decrypt the packet.
1400  * The format is not part of ABI, use av_encryption_info_* methods to access.
1401  */
1403 
1404  /**
1405  * Active Format Description data consisting of a single byte as specified
1406  * in ETSI TS 101 154 using AVActiveFormatDescription enum.
1407  */
1409 
1410  /**
1411  * The number of side data types.
1412  * This is not part of the public API/ABI in the sense that it may
1413  * change when new side data types are added.
1414  * This must stay the last enum value.
1415  * If its value becomes huge, some code using it
1416  * needs to be updated as it assumes it to be smaller than other limits.
1417  */
1419 };
1420 
1421 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1422 
1423 typedef struct AVPacketSideData {
1425  int size;
1428 
1429 /**
1430  * This structure stores compressed data. It is typically exported by demuxers
1431  * and then passed as input to decoders, or received as output from encoders and
1432  * then passed to muxers.
1433  *
1434  * For video, it should typically contain one compressed frame. For audio it may
1435  * contain several compressed frames. Encoders are allowed to output empty
1436  * packets, with no compressed data, containing only side data
1437  * (e.g. to update some stream parameters at the end of encoding).
1438  *
1439  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1440  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1441  * without libavcodec and libavformat major bump.
1442  *
1443  * The semantics of data ownership depends on the buf field.
1444  * If it is set, the packet data is dynamically allocated and is
1445  * valid indefinitely until a call to av_packet_unref() reduces the
1446  * reference count to 0.
1447  *
1448  * If the buf field is not set av_packet_ref() would make a copy instead
1449  * of increasing the reference count.
1450  *
1451  * The side data is always allocated with av_malloc(), copied by
1452  * av_packet_ref() and freed by av_packet_unref().
1453  *
1454  * @see av_packet_ref
1455  * @see av_packet_unref
1456  */
1457 typedef struct AVPacket {
1458  /**
1459  * A reference to the reference-counted buffer where the packet data is
1460  * stored.
1461  * May be NULL, then the packet data is not reference-counted.
1462  */
1464  /**
1465  * Presentation timestamp in AVStream->time_base units; the time at which
1466  * the decompressed packet will be presented to the user.
1467  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1468  * pts MUST be larger or equal to dts as presentation cannot happen before
1469  * decompression, unless one wants to view hex dumps. Some formats misuse
1470  * the terms dts and pts/cts to mean something different. Such timestamps
1471  * must be converted to true pts/dts before they are stored in AVPacket.
1472  */
1473  int64_t pts;
1474  /**
1475  * Decompression timestamp in AVStream->time_base units; the time at which
1476  * the packet is decompressed.
1477  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1478  */
1479  int64_t dts;
1481  int size;
1483  /**
1484  * A combination of AV_PKT_FLAG values
1485  */
1486  int flags;
1487  /**
1488  * Additional packet data that can be provided by the container.
1489  * Packet can contain several types of side information.
1490  */
1493 
1494  /**
1495  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1496  * Equals next_pts - this_pts in presentation order.
1497  */
1498  int64_t duration;
1499 
1500  int64_t pos; ///< byte position in stream, -1 if unknown
1501 
1502 #if FF_API_CONVERGENCE_DURATION
1503  /**
1504  * @deprecated Same as the duration field, but as int64_t. This was required
1505  * for Matroska subtitles, whose duration values could overflow when the
1506  * duration field was still an int.
1507  */
1510 #endif
1511 } AVPacket;
1512 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1513 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1514 /**
1515  * Flag is used to discard packets which are required to maintain valid
1516  * decoder state but are not required for output and should be dropped
1517  * after decoding.
1518  **/
1519 #define AV_PKT_FLAG_DISCARD 0x0004
1520 /**
1521  * The packet comes from a trusted source.
1522  *
1523  * Otherwise-unsafe constructs such as arbitrary pointers to data
1524  * outside the packet may be followed.
1525  */
1526 #define AV_PKT_FLAG_TRUSTED 0x0008
1527 /**
1528  * Flag is used to indicate packets that contain frames that can
1529  * be discarded by the decoder. I.e. Non-reference frames.
1530  */
1531 #define AV_PKT_FLAG_DISPOSABLE 0x0010
1532 
1533 
1539 };
1540 /**
1541  * @}
1542  */
1543 
1544 struct AVCodecInternal;
1545 
1549  AV_FIELD_TT, //< Top coded_first, top displayed first
1550  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1551  AV_FIELD_TB, //< Top coded first, bottom displayed first
1552  AV_FIELD_BT, //< Bottom coded first, top displayed first
1553 };
1554 
1555 /**
1556  * main external API structure.
1557  * New fields can be added to the end with minor version bumps.
1558  * Removal, reordering and changes to existing fields require a major
1559  * version bump.
1560  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1561  * applications.
1562  * The name string for AVOptions options matches the associated command line
1563  * parameter name and can be found in libavcodec/options_table.h
1564  * The AVOption/command line parameter names differ in some cases from the C
1565  * structure field names for historic reasons or brevity.
1566  * sizeof(AVCodecContext) must not be used outside libav*.
1567  */
1568 typedef struct AVCodecContext {
1569  /**
1570  * information on struct for av_log
1571  * - set by avcodec_alloc_context3
1572  */
1575 
1576  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1577  const struct AVCodec *codec;
1578  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1579 
1580  /**
1581  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1582  * This is used to work around some encoder bugs.
1583  * A demuxer should set this to what is stored in the field used to identify the codec.
1584  * If there are multiple such fields in a container then the demuxer should choose the one
1585  * which maximizes the information about the used codec.
1586  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1587  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1588  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1589  * first.
1590  * - encoding: Set by user, if not then the default based on codec_id will be used.
1591  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1592  */
1593  unsigned int codec_tag;
1594 
1595  void *priv_data;
1596 
1597  /**
1598  * Private context used for internal data.
1599  *
1600  * Unlike priv_data, this is not codec-specific. It is used in general
1601  * libavcodec functions.
1602  */
1603  struct AVCodecInternal *internal;
1604 
1605  /**
1606  * Private data of the user, can be used to carry app specific stuff.
1607  * - encoding: Set by user.
1608  * - decoding: Set by user.
1609  */
1610  void *opaque;
1611 
1612  /**
1613  * the average bitrate
1614  * - encoding: Set by user; unused for constant quantizer encoding.
1615  * - decoding: Set by user, may be overwritten by libavcodec
1616  * if this info is available in the stream
1617  */
1618  int64_t bit_rate;
1619 
1620  /**
1621  * number of bits the bitstream is allowed to diverge from the reference.
1622  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1623  * - encoding: Set by user; unused for constant quantizer encoding.
1624  * - decoding: unused
1625  */
1627 
1628  /**
1629  * Global quality for codecs which cannot change it per frame.
1630  * This should be proportional to MPEG-1/2/4 qscale.
1631  * - encoding: Set by user.
1632  * - decoding: unused
1633  */
1635 
1636  /**
1637  * - encoding: Set by user.
1638  * - decoding: unused
1639  */
1641 #define FF_COMPRESSION_DEFAULT -1
1642 
1643  /**
1644  * AV_CODEC_FLAG_*.
1645  * - encoding: Set by user.
1646  * - decoding: Set by user.
1647  */
1648  int flags;
1649 
1650  /**
1651  * AV_CODEC_FLAG2_*
1652  * - encoding: Set by user.
1653  * - decoding: Set by user.
1654  */
1655  int flags2;
1656 
1657  /**
1658  * some codecs need / can use extradata like Huffman tables.
1659  * MJPEG: Huffman tables
1660  * rv10: additional flags
1661  * MPEG-4: global headers (they can be in the bitstream or here)
1662  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1663  * than extradata_size to avoid problems if it is read with the bitstream reader.
1664  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1665  * Must be allocated with the av_malloc() family of functions.
1666  * - encoding: Set/allocated/freed by libavcodec.
1667  * - decoding: Set/allocated/freed by user.
1668  */
1671 
1672  /**
1673  * This is the fundamental unit of time (in seconds) in terms
1674  * of which frame timestamps are represented. For fixed-fps content,
1675  * timebase should be 1/framerate and timestamp increments should be
1676  * identically 1.
1677  * This often, but not always is the inverse of the frame rate or field rate
1678  * for video. 1/time_base is not the average frame rate if the frame rate is not
1679  * constant.
1680  *
1681  * Like containers, elementary streams also can store timestamps, 1/time_base
1682  * is the unit in which these timestamps are specified.
1683  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1684  * vop_time_increment_resolution and fixed_vop_rate
1685  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1686  *
1687  * - encoding: MUST be set by user.
1688  * - decoding: the use of this field for decoding is deprecated.
1689  * Use framerate instead.
1690  */
1692 
1693  /**
1694  * For some codecs, the time base is closer to the field rate than the frame rate.
1695  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1696  * if no telecine is used ...
1697  *
1698  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1699  */
1701 
1702  /**
1703  * Codec delay.
1704  *
1705  * Encoding: Number of frames delay there will be from the encoder input to
1706  * the decoder output. (we assume the decoder matches the spec)
1707  * Decoding: Number of frames delay in addition to what a standard decoder
1708  * as specified in the spec would produce.
1709  *
1710  * Video:
1711  * Number of frames the decoded output will be delayed relative to the
1712  * encoded input.
1713  *
1714  * Audio:
1715  * For encoding, this field is unused (see initial_padding).
1716  *
1717  * For decoding, this is the number of samples the decoder needs to
1718  * output before the decoder's output is valid. When seeking, you should
1719  * start decoding this many samples prior to your desired seek point.
1720  *
1721  * - encoding: Set by libavcodec.
1722  * - decoding: Set by libavcodec.
1723  */
1724  int delay;
1725 
1726 
1727  /* video only */
1728  /**
1729  * picture width / height.
1730  *
1731  * @note Those fields may not match the values of the last
1732  * AVFrame output by avcodec_decode_video2 due frame
1733  * reordering.
1734  *
1735  * - encoding: MUST be set by user.
1736  * - decoding: May be set by the user before opening the decoder if known e.g.
1737  * from the container. Some decoders will require the dimensions
1738  * to be set by the caller. During decoding, the decoder may
1739  * overwrite those values as required while parsing the data.
1740  */
1742 
1743  /**
1744  * Bitstream width / height, may be different from width/height e.g. when
1745  * the decoded frame is cropped before being output or lowres is enabled.
1746  *
1747  * @note Those field may not match the value of the last
1748  * AVFrame output by avcodec_receive_frame() due frame
1749  * reordering.
1750  *
1751  * - encoding: unused
1752  * - decoding: May be set by the user before opening the decoder if known
1753  * e.g. from the container. During decoding, the decoder may
1754  * overwrite those values as required while parsing the data.
1755  */
1756  int coded_width, coded_height;
1757 
1758  /**
1759  * the number of pictures in a group of pictures, or 0 for intra_only
1760  * - encoding: Set by user.
1761  * - decoding: unused
1762  */
1764 
1765  /**
1766  * Pixel format, see AV_PIX_FMT_xxx.
1767  * May be set by the demuxer if known from headers.
1768  * May be overridden by the decoder if it knows better.
1769  *
1770  * @note This field may not match the value of the last
1771  * AVFrame output by avcodec_receive_frame() due frame
1772  * reordering.
1773  *
1774  * - encoding: Set by user.
1775  * - decoding: Set by user if known, overridden by libavcodec while
1776  * parsing the data.
1777  */
1779 
1780  /**
1781  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1782  * decoder to draw a horizontal band. It improves cache usage. Not
1783  * all codecs can do that. You must check the codec capabilities
1784  * beforehand.
1785  * When multithreading is used, it may be called from multiple threads
1786  * at the same time; threads might draw different parts of the same AVFrame,
1787  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1788  * in order.
1789  * The function is also used by hardware acceleration APIs.
1790  * It is called at least once during frame decoding to pass
1791  * the data needed for hardware render.
1792  * In that mode instead of pixel data, AVFrame points to
1793  * a structure specific to the acceleration API. The application
1794  * reads the structure and can change some fields to indicate progress
1795  * or mark state.
1796  * - encoding: unused
1797  * - decoding: Set by user.
1798  * @param height the height of the slice
1799  * @param y the y position of the slice
1800  * @param type 1->top field, 2->bottom field, 3->frame
1801  * @param offset offset into the AVFrame.data from which the slice should be read
1802  */
1804  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1805  int y, int type, int height);
1806 
1807  /**
1808  * callback to negotiate the pixelFormat
1809  * @param fmt is the list of formats which are supported by the codec,
1810  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1811  * The first is always the native one.
1812  * @note The callback may be called again immediately if initialization for
1813  * the selected (hardware-accelerated) pixel format failed.
1814  * @warning Behavior is undefined if the callback returns a value not
1815  * in the fmt list of formats.
1816  * @return the chosen format
1817  * - encoding: unused
1818  * - decoding: Set by user, if not set the native format will be chosen.
1819  */
1820  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1821 
1822  /**
1823  * maximum number of B-frames between non-B-frames
1824  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1825  * - encoding: Set by user.
1826  * - decoding: unused
1827  */
1829 
1830  /**
1831  * qscale factor between IP and B-frames
1832  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1833  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1834  * - encoding: Set by user.
1835  * - decoding: unused
1836  */
1838 
1839 #if FF_API_PRIVATE_OPT
1840  /** @deprecated use encoder private options instead */
1843 #endif
1844 
1845  /**
1846  * qscale offset between IP and B-frames
1847  * - encoding: Set by user.
1848  * - decoding: unused
1849  */
1851 
1852  /**
1853  * Size of the frame reordering buffer in the decoder.
1854  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1855  * - encoding: Set by libavcodec.
1856  * - decoding: Set by libavcodec.
1857  */
1859 
1860 #if FF_API_PRIVATE_OPT
1861  /** @deprecated use encoder private options instead */
1864 #endif
1865 
1866  /**
1867  * qscale factor between P- and I-frames
1868  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1869  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1870  * - encoding: Set by user.
1871  * - decoding: unused
1872  */
1874 
1875  /**
1876  * qscale offset between P and I-frames
1877  * - encoding: Set by user.
1878  * - decoding: unused
1879  */
1881 
1882  /**
1883  * luminance masking (0-> disabled)
1884  * - encoding: Set by user.
1885  * - decoding: unused
1886  */
1888 
1889  /**
1890  * temporary complexity masking (0-> disabled)
1891  * - encoding: Set by user.
1892  * - decoding: unused
1893  */
1895 
1896  /**
1897  * spatial complexity masking (0-> disabled)
1898  * - encoding: Set by user.
1899  * - decoding: unused
1900  */
1902 
1903  /**
1904  * p block masking (0-> disabled)
1905  * - encoding: Set by user.
1906  * - decoding: unused
1907  */
1908  float p_masking;
1909 
1910  /**
1911  * darkness masking (0-> disabled)
1912  * - encoding: Set by user.
1913  * - decoding: unused
1914  */
1916 
1917  /**
1918  * slice count
1919  * - encoding: Set by libavcodec.
1920  * - decoding: Set by user (or 0).
1921  */
1923 
1924 #if FF_API_PRIVATE_OPT
1925  /** @deprecated use encoder private options instead */
1928 #define FF_PRED_LEFT 0
1929 #define FF_PRED_PLANE 1
1930 #define FF_PRED_MEDIAN 2
1931 #endif
1932 
1933  /**
1934  * slice offsets in the frame in bytes
1935  * - encoding: Set/allocated by libavcodec.
1936  * - decoding: Set/allocated by user (or NULL).
1937  */
1939 
1940  /**
1941  * sample aspect ratio (0 if unknown)
1942  * That is the width of a pixel divided by the height of the pixel.
1943  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1944  * - encoding: Set by user.
1945  * - decoding: Set by libavcodec.
1946  */
1948 
1949  /**
1950  * motion estimation comparison function
1951  * - encoding: Set by user.
1952  * - decoding: unused
1953  */
1954  int me_cmp;
1955  /**
1956  * subpixel motion estimation comparison function
1957  * - encoding: Set by user.
1958  * - decoding: unused
1959  */
1961  /**
1962  * macroblock comparison function (not supported yet)
1963  * - encoding: Set by user.
1964  * - decoding: unused
1965  */
1966  int mb_cmp;
1967  /**
1968  * interlaced DCT comparison function
1969  * - encoding: Set by user.
1970  * - decoding: unused
1971  */
1973 #define FF_CMP_SAD 0
1974 #define FF_CMP_SSE 1
1975 #define FF_CMP_SATD 2
1976 #define FF_CMP_DCT 3
1977 #define FF_CMP_PSNR 4
1978 #define FF_CMP_BIT 5
1979 #define FF_CMP_RD 6
1980 #define FF_CMP_ZERO 7
1981 #define FF_CMP_VSAD 8
1982 #define FF_CMP_VSSE 9
1983 #define FF_CMP_NSSE 10
1984 #define FF_CMP_W53 11
1985 #define FF_CMP_W97 12
1986 #define FF_CMP_DCTMAX 13
1987 #define FF_CMP_DCT264 14
1988 #define FF_CMP_MEDIAN_SAD 15
1989 #define FF_CMP_CHROMA 256
1990 
1991  /**
1992  * ME diamond size & shape
1993  * - encoding: Set by user.
1994  * - decoding: unused
1995  */
1997 
1998  /**
1999  * amount of previous MV predictors (2a+1 x 2a+1 square)
2000  * - encoding: Set by user.
2001  * - decoding: unused
2002  */
2004 
2005 #if FF_API_PRIVATE_OPT
2006  /** @deprecated use encoder private options instead */
2008  int pre_me;
2009 #endif
2010 
2011  /**
2012  * motion estimation prepass comparison function
2013  * - encoding: Set by user.
2014  * - decoding: unused
2015  */
2017 
2018  /**
2019  * ME prepass diamond size & shape
2020  * - encoding: Set by user.
2021  * - decoding: unused
2022  */
2024 
2025  /**
2026  * subpel ME quality
2027  * - encoding: Set by user.
2028  * - decoding: unused
2029  */
2031 
2032  /**
2033  * maximum motion estimation search range in subpel units
2034  * If 0 then no limit.
2035  *
2036  * - encoding: Set by user.
2037  * - decoding: unused
2038  */
2040 
2041  /**
2042  * slice flags
2043  * - encoding: unused
2044  * - decoding: Set by user.
2045  */
2047 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2048 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2049 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2050 
2051  /**
2052  * macroblock decision mode
2053  * - encoding: Set by user.
2054  * - decoding: unused
2055  */
2057 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2058 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2059 #define FF_MB_DECISION_RD 2 ///< rate distortion
2060 
2061  /**
2062  * custom intra quantization matrix
2063  * Must be allocated with the av_malloc() family of functions, and will be freed in
2064  * avcodec_free_context().
2065  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
2066  * - decoding: Set/allocated/freed by libavcodec.
2067  */
2068  uint16_t *intra_matrix;
2069 
2070  /**
2071  * custom inter quantization matrix
2072  * Must be allocated with the av_malloc() family of functions, and will be freed in
2073  * avcodec_free_context().
2074  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
2075  * - decoding: Set/allocated/freed by libavcodec.
2076  */
2077  uint16_t *inter_matrix;
2078 
2079 #if FF_API_PRIVATE_OPT
2080  /** @deprecated use encoder private options instead */
2083 
2084  /** @deprecated use encoder private options instead */
2087 #endif
2088 
2089  /**
2090  * precision of the intra DC coefficient - 8
2091  * - encoding: Set by user.
2092  * - decoding: Set by libavcodec
2093  */
2095 
2096  /**
2097  * Number of macroblock rows at the top which are skipped.
2098  * - encoding: unused
2099  * - decoding: Set by user.
2100  */
2102 
2103  /**
2104  * Number of macroblock rows at the bottom which are skipped.
2105  * - encoding: unused
2106  * - decoding: Set by user.
2107  */
2109 
2110  /**
2111  * minimum MB Lagrange multiplier
2112  * - encoding: Set by user.
2113  * - decoding: unused
2114  */
2115  int mb_lmin;
2116 
2117  /**
2118  * maximum MB Lagrange multiplier
2119  * - encoding: Set by user.
2120  * - decoding: unused
2121  */
2122  int mb_lmax;
2123 
2124 #if FF_API_PRIVATE_OPT
2125  /**
2126  * @deprecated use encoder private options instead
2127  */
2130 #endif
2131 
2132  /**
2133  * - encoding: Set by user.
2134  * - decoding: unused
2135  */
2137 
2138 #if FF_API_PRIVATE_OPT
2139  /** @deprecated use encoder private options instead */
2142 #endif
2143 
2144  /**
2145  * minimum GOP size
2146  * - encoding: Set by user.
2147  * - decoding: unused
2148  */
2150 
2151  /**
2152  * number of reference frames
2153  * - encoding: Set by user.
2154  * - decoding: Set by lavc.
2155  */
2156  int refs;
2157 
2158 #if FF_API_PRIVATE_OPT
2159  /** @deprecated use encoder private options instead */
2162 #endif
2163 
2164  /**
2165  * Note: Value depends upon the compare function used for fullpel ME.
2166  * - encoding: Set by user.
2167  * - decoding: unused
2168  */
2170 
2171 #if FF_API_PRIVATE_OPT
2172  /** @deprecated use encoder private options instead */
2175 #endif
2176 
2177  /**
2178  * Chromaticity coordinates of the source primaries.
2179  * - encoding: Set by user
2180  * - decoding: Set by libavcodec
2181  */
2183 
2184  /**
2185  * Color Transfer Characteristic.
2186  * - encoding: Set by user
2187  * - decoding: Set by libavcodec
2188  */
2190 
2191  /**
2192  * YUV colorspace type.
2193  * - encoding: Set by user
2194  * - decoding: Set by libavcodec
2195  */
2197 
2198  /**
2199  * MPEG vs JPEG YUV range.
2200  * - encoding: Set by user
2201  * - decoding: Set by libavcodec
2202  */
2204 
2205  /**
2206  * This defines the location of chroma samples.
2207  * - encoding: Set by user
2208  * - decoding: Set by libavcodec
2209  */
2211 
2212  /**
2213  * Number of slices.
2214  * Indicates number of picture subdivisions. Used for parallelized
2215  * decoding.
2216  * - encoding: Set by user
2217  * - decoding: unused
2218  */
2219  int slices;
2220 
2221  /** Field order
2222  * - encoding: set by libavcodec
2223  * - decoding: Set by user.
2224  */
2226 
2227  /* audio only */
2228  int sample_rate; ///< samples per second
2229  int channels; ///< number of audio channels
2230 
2231  /**
2232  * audio sample format
2233  * - encoding: Set by user.
2234  * - decoding: Set by libavcodec.
2235  */
2236  enum AVSampleFormat sample_fmt; ///< sample format
2237 
2238  /* The following data should not be initialized. */
2239  /**
2240  * Number of samples per channel in an audio frame.
2241  *
2242  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2243  * except the last must contain exactly frame_size samples per channel.
2244  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2245  * frame size is not restricted.
2246  * - decoding: may be set by some decoders to indicate constant frame size
2247  */
2249 
2250  /**
2251  * Frame counter, set by libavcodec.
2252  *
2253  * - decoding: total number of frames returned from the decoder so far.
2254  * - encoding: total number of frames passed to the encoder so far.
2255  *
2256  * @note the counter is not incremented if encoding/decoding resulted in
2257  * an error.
2258  */
2260 
2261  /**
2262  * number of bytes per packet if constant and known or 0
2263  * Used by some WAV based audio codecs.
2264  */
2266 
2267  /**
2268  * Audio cutoff bandwidth (0 means "automatic")
2269  * - encoding: Set by user.
2270  * - decoding: unused
2271  */
2272  int cutoff;
2273 
2274  /**
2275  * Audio channel layout.
2276  * - encoding: set by user.
2277  * - decoding: set by user, may be overwritten by libavcodec.
2278  */
2279  uint64_t channel_layout;
2280 
2281  /**
2282  * Request decoder to use this channel layout if it can (0 for default)
2283  * - encoding: unused
2284  * - decoding: Set by user.
2285  */
2287 
2288  /**
2289  * Type of service that the audio stream conveys.
2290  * - encoding: Set by user.
2291  * - decoding: Set by libavcodec.
2292  */
2294 
2295  /**
2296  * desired sample format
2297  * - encoding: Not used.
2298  * - decoding: Set by user.
2299  * Decoder will decode to this format if it can.
2300  */
2302 
2303  /**
2304  * This callback is called at the beginning of each frame to get data
2305  * buffer(s) for it. There may be one contiguous buffer for all the data or
2306  * there may be a buffer per each data plane or anything in between. What
2307  * this means is, you may set however many entries in buf[] you feel necessary.
2308  * Each buffer must be reference-counted using the AVBuffer API (see description
2309  * of buf[] below).
2310  *
2311  * The following fields will be set in the frame before this callback is
2312  * called:
2313  * - format
2314  * - width, height (video only)
2315  * - sample_rate, channel_layout, nb_samples (audio only)
2316  * Their values may differ from the corresponding values in
2317  * AVCodecContext. This callback must use the frame values, not the codec
2318  * context values, to calculate the required buffer size.
2319  *
2320  * This callback must fill the following fields in the frame:
2321  * - data[]
2322  * - linesize[]
2323  * - extended_data:
2324  * * if the data is planar audio with more than 8 channels, then this
2325  * callback must allocate and fill extended_data to contain all pointers
2326  * to all data planes. data[] must hold as many pointers as it can.
2327  * extended_data must be allocated with av_malloc() and will be freed in
2328  * av_frame_unref().
2329  * * otherwise extended_data must point to data
2330  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2331  * the frame's data and extended_data pointers must be contained in these. That
2332  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2333  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2334  * and av_buffer_ref().
2335  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2336  * this callback and filled with the extra buffers if there are more
2337  * buffers than buf[] can hold. extended_buf will be freed in
2338  * av_frame_unref().
2339  *
2340  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2341  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2342  * some other means.
2343  *
2344  * Each data plane must be aligned to the maximum required by the target
2345  * CPU.
2346  *
2347  * @see avcodec_default_get_buffer2()
2348  *
2349  * Video:
2350  *
2351  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2352  * (read and/or written to if it is writable) later by libavcodec.
2353  *
2354  * avcodec_align_dimensions2() should be used to find the required width and
2355  * height, as they normally need to be rounded up to the next multiple of 16.
2356  *
2357  * Some decoders do not support linesizes changing between frames.
2358  *
2359  * If frame multithreading is used and thread_safe_callbacks is set,
2360  * this callback may be called from a different thread, but not from more
2361  * than one at once. Does not need to be reentrant.
2362  *
2363  * @see avcodec_align_dimensions2()
2364  *
2365  * Audio:
2366  *
2367  * Decoders request a buffer of a particular size by setting
2368  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2369  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2370  * to a smaller value in the output frame.
2371  *
2372  * As a convenience, av_samples_get_buffer_size() and
2373  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2374  * functions to find the required data size and to fill data pointers and
2375  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2376  * since all planes must be the same size.
2377  *
2378  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2379  *
2380  * - encoding: unused
2381  * - decoding: Set by libavcodec, user can override.
2382  */
2384 
2385  /**
2386  * If non-zero, the decoded audio and video frames returned from
2387  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2388  * and are valid indefinitely. The caller must free them with
2389  * av_frame_unref() when they are not needed anymore.
2390  * Otherwise, the decoded frames must not be freed by the caller and are
2391  * only valid until the next decode call.
2392  *
2393  * This is always automatically enabled if avcodec_receive_frame() is used.
2394  *
2395  * - encoding: unused
2396  * - decoding: set by the caller before avcodec_open2().
2397  */
2400 
2401  /* - encoding parameters */
2402  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2403  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2404 
2405  /**
2406  * minimum quantizer
2407  * - encoding: Set by user.
2408  * - decoding: unused
2409  */
2410  int qmin;
2411 
2412  /**
2413  * maximum quantizer
2414  * - encoding: Set by user.
2415  * - decoding: unused
2416  */
2417  int qmax;
2418 
2419  /**
2420  * maximum quantizer difference between frames
2421  * - encoding: Set by user.
2422  * - decoding: unused
2423  */
2425 
2426  /**
2427  * decoder bitstream buffer size
2428  * - encoding: Set by user.
2429  * - decoding: unused
2430  */
2432 
2433  /**
2434  * ratecontrol override, see RcOverride
2435  * - encoding: Allocated/set/freed by user.
2436  * - decoding: unused
2437  */
2440 
2441  /**
2442  * maximum bitrate
2443  * - encoding: Set by user.
2444  * - decoding: Set by user, may be overwritten by libavcodec.
2445  */
2446  int64_t rc_max_rate;
2447 
2448  /**
2449  * minimum bitrate
2450  * - encoding: Set by user.
2451  * - decoding: unused
2452  */
2453  int64_t rc_min_rate;
2454 
2455  /**
2456  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2457  * - encoding: Set by user.
2458  * - decoding: unused.
2459  */
2461 
2462  /**
2463  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2464  * - encoding: Set by user.
2465  * - decoding: unused.
2466  */
2468 
2469  /**
2470  * Number of bits which should be loaded into the rc buffer before decoding starts.
2471  * - encoding: Set by user.
2472  * - decoding: unused
2473  */
2475 
2476 #if FF_API_CODER_TYPE
2477 #define FF_CODER_TYPE_VLC 0
2478 #define FF_CODER_TYPE_AC 1
2479 #define FF_CODER_TYPE_RAW 2
2480 #define FF_CODER_TYPE_RLE 3
2481  /**
2482  * @deprecated use encoder private options instead
2483  */
2486 #endif /* FF_API_CODER_TYPE */
2487 
2488 #if FF_API_PRIVATE_OPT
2489  /** @deprecated use encoder private options instead */
2492 #endif
2493 
2494 #if FF_API_PRIVATE_OPT
2495  /** @deprecated use encoder private options instead */
2498 
2499  /** @deprecated use encoder private options instead */
2502 
2503  /** @deprecated use encoder private options instead */
2506 
2507  /** @deprecated use encoder private options instead */
2510 #endif /* FF_API_PRIVATE_OPT */
2511 
2512  /**
2513  * trellis RD quantization
2514  * - encoding: Set by user.
2515  * - decoding: unused
2516  */
2517  int trellis;
2518 
2519 #if FF_API_PRIVATE_OPT
2520  /** @deprecated use encoder private options instead */
2523 
2524  /** @deprecated use encoder private options instead */
2527 
2528  /** @deprecated use encoder private options instead */
2531 #endif
2532 
2533 #if FF_API_RTP_CALLBACK
2534  /**
2535  * @deprecated unused
2536  */
2537  /* The RTP callback: This function is called */
2538  /* every time the encoder has a packet to send. */
2539  /* It depends on the encoder if the data starts */
2540  /* with a Start Code (it should). H.263 does. */
2541  /* mb_nb contains the number of macroblocks */
2542  /* encoded in the RTP payload. */
2544  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2545 #endif
2546 
2547 #if FF_API_PRIVATE_OPT
2548  /** @deprecated use encoder private options instead */
2550  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2551  /* do its best to deliver a chunk with size */
2552  /* below rtp_payload_size, the chunk will start */
2553  /* with a start code on some codecs like H.263. */
2554  /* This doesn't take account of any particular */
2555  /* headers inside the transmitted RTP payload. */
2556 #endif
2557 
2558 #if FF_API_STAT_BITS
2559  /* statistics, used for 2-pass encoding */
2561  int mv_bits;
2569  int i_count;
2571  int p_count;
2576 
2577  /** @deprecated this field is unused */
2580 #endif
2581 
2582  /**
2583  * pass1 encoding statistics output buffer
2584  * - encoding: Set by libavcodec.
2585  * - decoding: unused
2586  */
2587  char *stats_out;
2588 
2589  /**
2590  * pass2 encoding statistics input buffer
2591  * Concatenated stuff from stats_out of pass1 should be placed here.
2592  * - encoding: Allocated/set/freed by user.
2593  * - decoding: unused
2594  */
2595  char *stats_in;
2596 
2597  /**
2598  * Work around bugs in encoders which sometimes cannot be detected automatically.
2599  * - encoding: Set by user
2600  * - decoding: Set by user
2601  */
2603 #define FF_BUG_AUTODETECT 1 ///< autodetection
2604 #define FF_BUG_XVID_ILACE 4
2605 #define FF_BUG_UMP4 8
2606 #define FF_BUG_NO_PADDING 16
2607 #define FF_BUG_AMV 32
2608 #define FF_BUG_QPEL_CHROMA 64
2609 #define FF_BUG_STD_QPEL 128
2610 #define FF_BUG_QPEL_CHROMA2 256
2611 #define FF_BUG_DIRECT_BLOCKSIZE 512
2612 #define FF_BUG_EDGE 1024
2613 #define FF_BUG_HPEL_CHROMA 2048
2614 #define FF_BUG_DC_CLIP 4096
2615 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2616 #define FF_BUG_TRUNCATED 16384
2617 #define FF_BUG_IEDGE 32768
2618 
2619  /**
2620  * strictly follow the standard (MPEG-4, ...).
2621  * - encoding: Set by user.
2622  * - decoding: Set by user.
2623  * Setting this to STRICT or higher means the encoder and decoder will
2624  * generally do stupid things, whereas setting it to unofficial or lower
2625  * will mean the encoder might produce output that is not supported by all
2626  * spec-compliant decoders. Decoders don't differentiate between normal,
2627  * unofficial and experimental (that is, they always try to decode things
2628  * when they can) unless they are explicitly asked to behave stupidly
2629  * (=strictly conform to the specs)
2630  */
2632 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2633 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2634 #define FF_COMPLIANCE_NORMAL 0
2635 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2636 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2637 
2638  /**
2639  * error concealment flags
2640  * - encoding: unused
2641  * - decoding: Set by user.
2642  */
2644 #define FF_EC_GUESS_MVS 1
2645 #define FF_EC_DEBLOCK 2
2646 #define FF_EC_FAVOR_INTER 256
2647 
2648  /**
2649  * debug
2650  * - encoding: Set by user.
2651  * - decoding: Set by user.
2652  */
2653  int debug;
2654 #define FF_DEBUG_PICT_INFO 1
2655 #define FF_DEBUG_RC 2
2656 #define FF_DEBUG_BITSTREAM 4
2657 #define FF_DEBUG_MB_TYPE 8
2658 #define FF_DEBUG_QP 16
2659 #if FF_API_DEBUG_MV
2660 /**
2661  * @deprecated this option does nothing
2662  */
2663 #define FF_DEBUG_MV 32
2664 #endif
2665 #define FF_DEBUG_DCT_COEFF 0x00000040
2666 #define FF_DEBUG_SKIP 0x00000080
2667 #define FF_DEBUG_STARTCODE 0x00000100
2668 #define FF_DEBUG_ER 0x00000400
2669 #define FF_DEBUG_MMCO 0x00000800
2670 #define FF_DEBUG_BUGS 0x00001000
2671 #if FF_API_DEBUG_MV
2672 #define FF_DEBUG_VIS_QP 0x00002000
2673 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2674 #endif
2675 #define FF_DEBUG_BUFFERS 0x00008000
2676 #define FF_DEBUG_THREADS 0x00010000
2677 #define FF_DEBUG_GREEN_MD 0x00800000
2678 #define FF_DEBUG_NOMC 0x01000000
2679 
2680 #if FF_API_DEBUG_MV
2681  /**
2682  * debug
2683  * - encoding: Set by user.
2684  * - decoding: Set by user.
2685  */
2686  int debug_mv;
2687 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2688 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2689 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2690 #endif
2691 
2692  /**
2693  * Error recognition; may misdetect some more or less valid parts as errors.
2694  * - encoding: unused
2695  * - decoding: Set by user.
2696  */
2698 
2699 /**
2700  * Verify checksums embedded in the bitstream (could be of either encoded or
2701  * decoded data, depending on the codec) and print an error message on mismatch.
2702  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2703  * decoder returning an error.
2704  */
2705 #define AV_EF_CRCCHECK (1<<0)
2706 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2707 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2708 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2709 
2710 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2711 #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
2712 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2713 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2714 
2715 
2716  /**
2717  * opaque 64-bit number (generally a PTS) that will be reordered and
2718  * output in AVFrame.reordered_opaque
2719  * - encoding: Set by libavcodec to the reordered_opaque of the input
2720  * frame corresponding to the last returned packet. Only
2721  * supported by encoders with the
2722  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
2723  * - decoding: Set by user.
2724  */
2726 
2727  /**
2728  * Hardware accelerator in use
2729  * - encoding: unused.
2730  * - decoding: Set by libavcodec
2731  */
2732  const struct AVHWAccel *hwaccel;
2733 
2734  /**
2735  * Hardware accelerator context.
2736  * For some hardware accelerators, a global context needs to be
2737  * provided by the user. In that case, this holds display-dependent
2738  * data FFmpeg cannot instantiate itself. Please refer to the
2739  * FFmpeg HW accelerator documentation to know how to fill this
2740  * is. e.g. for VA API, this is a struct vaapi_context.
2741  * - encoding: unused
2742  * - decoding: Set by user
2743  */
2745 
2746  /**
2747  * error
2748  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2749  * - decoding: unused
2750  */
2752 
2753  /**
2754  * DCT algorithm, see FF_DCT_* below
2755  * - encoding: Set by user.
2756  * - decoding: unused
2757  */
2759 #define FF_DCT_AUTO 0
2760 #define FF_DCT_FASTINT 1
2761 #define FF_DCT_INT 2
2762 #define FF_DCT_MMX 3
2763 #define FF_DCT_ALTIVEC 5
2764 #define FF_DCT_FAAN 6
2765 
2766  /**
2767  * IDCT algorithm, see FF_IDCT_* below.
2768  * - encoding: Set by user.
2769  * - decoding: Set by user.
2770  */
2772 #define FF_IDCT_AUTO 0
2773 #define FF_IDCT_INT 1
2774 #define FF_IDCT_SIMPLE 2
2775 #define FF_IDCT_SIMPLEMMX 3
2776 #define FF_IDCT_ARM 7
2777 #define FF_IDCT_ALTIVEC 8
2778 #define FF_IDCT_SIMPLEARM 10
2779 #define FF_IDCT_XVID 14
2780 #define FF_IDCT_SIMPLEARMV5TE 16
2781 #define FF_IDCT_SIMPLEARMV6 17
2782 #define FF_IDCT_FAAN 20
2783 #define FF_IDCT_SIMPLENEON 22
2784 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2785 #define FF_IDCT_SIMPLEAUTO 128
2786 
2787  /**
2788  * bits per sample/pixel from the demuxer (needed for huffyuv).
2789  * - encoding: Set by libavcodec.
2790  * - decoding: Set by user.
2791  */
2793 
2794  /**
2795  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2796  * - encoding: set by user.
2797  * - decoding: set by libavcodec.
2798  */
2800 
2801 #if FF_API_LOWRES
2802  /**
2803  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2804  * - encoding: unused
2805  * - decoding: Set by user.
2806  */
2807  int lowres;
2808 #endif
2809 
2810 #if FF_API_CODED_FRAME
2811  /**
2812  * the picture in the bitstream
2813  * - encoding: Set by libavcodec.
2814  * - decoding: unused
2815  *
2816  * @deprecated use the quality factor packet side data instead
2817  */
2819 #endif
2820 
2821  /**
2822  * thread count
2823  * is used to decide how many independent tasks should be passed to execute()
2824  * - encoding: Set by user.
2825  * - decoding: Set by user.
2826  */
2828 
2829  /**
2830  * Which multithreading methods to use.
2831  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2832  * so clients which cannot provide future frames should not use it.
2833  *
2834  * - encoding: Set by user, otherwise the default is used.
2835  * - decoding: Set by user, otherwise the default is used.
2836  */
2838 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2839 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2840 
2841  /**
2842  * Which multithreading methods are in use by the codec.
2843  * - encoding: Set by libavcodec.
2844  * - decoding: Set by libavcodec.
2845  */
2847 
2848  /**
2849  * Set by the client if its custom get_buffer() callback can be called
2850  * synchronously from another thread, which allows faster multithreaded decoding.
2851  * draw_horiz_band() will be called from other threads regardless of this setting.
2852  * Ignored if the default get_buffer() is used.
2853  * - encoding: Set by user.
2854  * - decoding: Set by user.
2855  */
2857 
2858  /**
2859  * The codec may call this to execute several independent things.
2860  * It will return only after finishing all tasks.
2861  * The user may replace this with some multithreaded implementation,
2862  * the default implementation will execute the parts serially.
2863  * @param count the number of things to execute
2864  * - encoding: Set by libavcodec, user can override.
2865  * - decoding: Set by libavcodec, user can override.
2866  */
2867  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2868 
2869  /**
2870  * The codec may call this to execute several independent things.
2871  * It will return only after finishing all tasks.
2872  * The user may replace this with some multithreaded implementation,
2873  * the default implementation will execute the parts serially.
2874  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2875  * @param c context passed also to func
2876  * @param count the number of things to execute
2877  * @param arg2 argument passed unchanged to func
2878  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2879  * @param func function that will be called count times, with jobnr from 0 to count-1.
2880  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2881  * two instances of func executing at the same time will have the same threadnr.
2882  * @return always 0 currently, but code should handle a future improvement where when any call to func
2883  * returns < 0 no further calls to func may be done and < 0 is returned.
2884  * - encoding: Set by libavcodec, user can override.
2885  * - decoding: Set by libavcodec, user can override.
2886  */
2887  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2888 
2889  /**
2890  * noise vs. sse weight for the nsse comparison function
2891  * - encoding: Set by user.
2892  * - decoding: unused
2893  */
2895 
2896  /**
2897  * profile
2898  * - encoding: Set by user.
2899  * - decoding: Set by libavcodec.
2900  */
2901  int profile;
2902 #define FF_PROFILE_UNKNOWN -99
2903 #define FF_PROFILE_RESERVED -100
2904 
2905 #define FF_PROFILE_AAC_MAIN 0
2906 #define FF_PROFILE_AAC_LOW 1
2907 #define FF_PROFILE_AAC_SSR 2
2908 #define FF_PROFILE_AAC_LTP 3
2909 #define FF_PROFILE_AAC_HE 4
2910 #define FF_PROFILE_AAC_HE_V2 28
2911 #define FF_PROFILE_AAC_LD 22
2912 #define FF_PROFILE_AAC_ELD 38
2913 #define FF_PROFILE_MPEG2_AAC_LOW 128
2914 #define FF_PROFILE_MPEG2_AAC_HE 131
2915 
2916 #define FF_PROFILE_DNXHD 0
2917 #define FF_PROFILE_DNXHR_LB 1
2918 #define FF_PROFILE_DNXHR_SQ 2
2919 #define FF_PROFILE_DNXHR_HQ 3
2920 #define FF_PROFILE_DNXHR_HQX 4
2921 #define FF_PROFILE_DNXHR_444 5
2922 
2923 #define FF_PROFILE_DTS 20
2924 #define FF_PROFILE_DTS_ES 30
2925 #define FF_PROFILE_DTS_96_24 40
2926 #define FF_PROFILE_DTS_HD_HRA 50
2927 #define FF_PROFILE_DTS_HD_MA 60
2928 #define FF_PROFILE_DTS_EXPRESS 70
2929 
2930 #define FF_PROFILE_MPEG2_422 0
2931 #define FF_PROFILE_MPEG2_HIGH 1
2932 #define FF_PROFILE_MPEG2_SS 2
2933 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2934 #define FF_PROFILE_MPEG2_MAIN 4
2935 #define FF_PROFILE_MPEG2_SIMPLE 5
2936 
2937 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2938 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2939 
2940 #define FF_PROFILE_H264_BASELINE 66
2941 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2942 #define FF_PROFILE_H264_MAIN 77
2943 #define FF_PROFILE_H264_EXTENDED 88
2944 #define FF_PROFILE_H264_HIGH 100
2945 #define FF_PROFILE_H264_HIGH_10 110
2946 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2947 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2948 #define FF_PROFILE_H264_HIGH_422 122
2949 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2950 #define FF_PROFILE_H264_STEREO_HIGH 128
2951 #define FF_PROFILE_H264_HIGH_444 144
2952 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2953 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2954 #define FF_PROFILE_H264_CAVLC_444 44
2955 
2956 #define FF_PROFILE_VC1_SIMPLE 0
2957 #define FF_PROFILE_VC1_MAIN 1
2958 #define FF_PROFILE_VC1_COMPLEX 2
2959 #define FF_PROFILE_VC1_ADVANCED 3
2960 
2961 #define FF_PROFILE_MPEG4_SIMPLE 0
2962 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2963 #define FF_PROFILE_MPEG4_CORE 2
2964 #define FF_PROFILE_MPEG4_MAIN 3
2965 #define FF_PROFILE_MPEG4_N_BIT 4
2966 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2967 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2968 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2969 #define FF_PROFILE_MPEG4_HYBRID 8
2970 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2971 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2972 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2973 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2974 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2975 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2976 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2977 
2978 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2979 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2980 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2981 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2982 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2983 
2984 #define FF_PROFILE_VP9_0 0
2985 #define FF_PROFILE_VP9_1 1
2986 #define FF_PROFILE_VP9_2 2
2987 #define FF_PROFILE_VP9_3 3
2988 
2989 #define FF_PROFILE_HEVC_MAIN 1
2990 #define FF_PROFILE_HEVC_MAIN_10 2
2991 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2992 #define FF_PROFILE_HEVC_REXT 4
2993 
2994 #define FF_PROFILE_AV1_MAIN 0
2995 #define FF_PROFILE_AV1_HIGH 1
2996 #define FF_PROFILE_AV1_PROFESSIONAL 2
2997 
2998 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
2999 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
3000 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
3001 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
3002 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
3003 
3004 #define FF_PROFILE_SBC_MSBC 1
3005 
3006 #define FF_PROFILE_PRORES_PROXY 0
3007 #define FF_PROFILE_PRORES_LT 1
3008 #define FF_PROFILE_PRORES_STANDARD 2
3009 #define FF_PROFILE_PRORES_HQ 3
3010 #define FF_PROFILE_PRORES_4444 4
3011 #define FF_PROFILE_PRORES_XQ 5
3012 
3013 #define FF_PROFILE_ARIB_PROFILE_A 0
3014 #define FF_PROFILE_ARIB_PROFILE_C 1
3015 
3016  /**
3017  * level
3018  * - encoding: Set by user.
3019  * - decoding: Set by libavcodec.
3020  */
3021  int level;
3022 #define FF_LEVEL_UNKNOWN -99
3023 
3024  /**
3025  * Skip loop filtering for selected frames.
3026  * - encoding: unused
3027  * - decoding: Set by user.
3028  */
3030 
3031  /**
3032  * Skip IDCT/dequantization for selected frames.
3033  * - encoding: unused
3034  * - decoding: Set by user.
3035  */
3037 
3038  /**
3039  * Skip decoding for selected frames.
3040  * - encoding: unused
3041  * - decoding: Set by user.
3042  */
3044 
3045  /**
3046  * Header containing style information for text subtitles.
3047  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3048  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3049  * the Format line following. It shouldn't include any Dialogue line.
3050  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3051  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3052  */
3055 
3056 #if FF_API_VBV_DELAY
3057  /**
3058  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3059  * Used for compliant TS muxing.
3060  * - encoding: Set by libavcodec.
3061  * - decoding: unused.
3062  * @deprecated this value is now exported as a part of
3063  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3064  */
3066  uint64_t vbv_delay;
3067 #endif
3068 
3069 #if FF_API_SIDEDATA_ONLY_PKT
3070  /**
3071  * Encoding only and set by default. Allow encoders to output packets
3072  * that do not contain any encoded data, only side data.
3073  *
3074  * Some encoders need to output such packets, e.g. to update some stream
3075  * parameters at the end of encoding.
3076  *
3077  * @deprecated this field disables the default behaviour and
3078  * it is kept only for compatibility.
3079  */
3082 #endif
3083 
3084  /**
3085  * Audio only. The number of "priming" samples (padding) inserted by the
3086  * encoder at the beginning of the audio. I.e. this number of leading
3087  * decoded samples must be discarded by the caller to get the original audio
3088  * without leading padding.
3089  *
3090  * - decoding: unused
3091  * - encoding: Set by libavcodec. The timestamps on the output packets are
3092  * adjusted by the encoder so that they always refer to the
3093  * first sample of the data actually contained in the packet,
3094  * including any added padding. E.g. if the timebase is
3095  * 1/samplerate and the timestamp of the first input sample is
3096  * 0, the timestamp of the first output packet will be
3097  * -initial_padding.
3098  */
3100 
3101  /**
3102  * - decoding: For codecs that store a framerate value in the compressed
3103  * bitstream, the decoder may export it here. { 0, 1} when
3104  * unknown.
3105  * - encoding: May be used to signal the framerate of CFR content to an
3106  * encoder.
3107  */
3109 
3110  /**
3111  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3112  * - encoding: unused.
3113  * - decoding: Set by libavcodec before calling get_format()
3114  */
3116 
3117  /**
3118  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3119  * - encoding unused.
3120  * - decoding set by user.
3121  */
3123 
3124  /**
3125  * AVCodecDescriptor
3126  * - encoding: unused.
3127  * - decoding: set by libavcodec.
3128  */
3130 
3131 #if !FF_API_LOWRES
3132  /**
3133  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3134  * - encoding: unused
3135  * - decoding: Set by user.
3136  */
3137  int lowres;
3138 #endif
3139 
3140  /**
3141  * Current statistics for PTS correction.
3142  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3143  * - encoding: unused
3144  */
3145  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3146  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3147  int64_t pts_correction_last_pts; /// PTS of the last frame
3148  int64_t pts_correction_last_dts; /// DTS of the last frame
3149 
3150  /**
3151  * Character encoding of the input subtitles file.
3152  * - decoding: set by user
3153  * - encoding: unused
3154  */
3156 
3157  /**
3158  * Subtitles character encoding mode. Formats or codecs might be adjusting
3159  * this setting (if they are doing the conversion themselves for instance).
3160  * - decoding: set by libavcodec
3161  * - encoding: unused
3162  */
3164 #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)
3165 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3166 #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
3167 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
3168 
3169  /**
3170  * Skip processing alpha if supported by codec.
3171  * Note that if the format uses pre-multiplied alpha (common with VP6,
3172  * and recommended due to better video quality/compression)
3173  * the image will look as if alpha-blended onto a black background.
3174  * However for formats that do not use pre-multiplied alpha
3175  * there might be serious artefacts (though e.g. libswscale currently
3176  * assumes pre-multiplied alpha anyway).
3177  *
3178  * - decoding: set by user
3179  * - encoding: unused
3180  */
3182 
3183  /**
3184  * Number of samples to skip after a discontinuity
3185  * - decoding: unused
3186  * - encoding: set by libavcodec
3187  */
3189 
3190 #if !FF_API_DEBUG_MV
3191  /**
3192  * debug motion vectors
3193  * - encoding: Set by user.
3194  * - decoding: Set by user.
3195  */
3197 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3198 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3199 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3200 #endif
3201 
3202  /**
3203  * custom intra quantization matrix
3204  * - encoding: Set by user, can be NULL.
3205  * - decoding: unused.
3206  */
3208 
3209  /**
3210  * dump format separator.
3211  * can be ", " or "\n " or anything else
3212  * - encoding: Set by user.
3213  * - decoding: Set by user.
3214  */
3216 
3217  /**
3218  * ',' separated list of allowed decoders.
3219  * If NULL then all are allowed
3220  * - encoding: unused
3221  * - decoding: set by user
3222  */
3224 
3225  /**
3226  * Properties of the stream that gets decoded
3227  * - encoding: unused
3228  * - decoding: set by libavcodec
3229  */
3230  unsigned properties;
3231 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3232 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3233 
3234  /**
3235  * Additional data associated with the entire coded stream.
3236  *
3237  * - decoding: unused
3238  * - encoding: may be set by libavcodec after avcodec_open2().
3239  */
3242 
3243  /**
3244  * A reference to the AVHWFramesContext describing the input (for encoding)
3245  * or output (decoding) frames. The reference is set by the caller and
3246  * afterwards owned (and freed) by libavcodec - it should never be read by
3247  * the caller after being set.
3248  *
3249  * - decoding: This field should be set by the caller from the get_format()
3250  * callback. The previous reference (if any) will always be
3251  * unreffed by libavcodec before the get_format() call.
3252  *
3253  * If the default get_buffer2() is used with a hwaccel pixel
3254  * format, then this AVHWFramesContext will be used for
3255  * allocating the frame buffers.
3256  *
3257  * - encoding: For hardware encoders configured to use a hwaccel pixel
3258  * format, this field should be set by the caller to a reference
3259  * to the AVHWFramesContext describing input frames.
3260  * AVHWFramesContext.format must be equal to
3261  * AVCodecContext.pix_fmt.
3262  *
3263  * This field should be set before avcodec_open2() is called.
3264  */
3266 
3267  /**
3268  * Control the form of AVSubtitle.rects[N]->ass
3269  * - decoding: set by user
3270  * - encoding: unused
3271  */
3273 #define FF_SUB_TEXT_FMT_ASS 0
3274 #if FF_API_ASS_TIMING
3275 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3276 #endif
3277 
3278  /**
3279  * Audio only. The amount of padding (in samples) appended by the encoder to
3280  * the end of the audio. I.e. this number of decoded samples must be
3281  * discarded by the caller from the end of the stream to get the original
3282  * audio without any trailing padding.
3283  *
3284  * - decoding: unused
3285  * - encoding: unused
3286  */
3288 
3289  /**
3290  * The number of pixels per image to maximally accept.
3291  *
3292  * - decoding: set by user
3293  * - encoding: set by user
3294  */
3295  int64_t max_pixels;
3296 
3297  /**
3298  * A reference to the AVHWDeviceContext describing the device which will
3299  * be used by a hardware encoder/decoder. The reference is set by the
3300  * caller and afterwards owned (and freed) by libavcodec.
3301  *
3302  * This should be used if either the codec device does not require
3303  * hardware frames or any that are used are to be allocated internally by
3304  * libavcodec. If the user wishes to supply any of the frames used as
3305  * encoder input or decoder output then hw_frames_ctx should be used
3306  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3307  * field will be ignored while decoding the associated stream segment, but
3308  * may again be used on a following one after another get_format() call.
3309  *
3310  * For both encoders and decoders this field should be set before
3311  * avcodec_open2() is called and must not be written to thereafter.
3312  *
3313  * Note that some decoders may require this field to be set initially in
3314  * order to support hw_frames_ctx at all - in that case, all frames
3315  * contexts used must be created on the same device.
3316  */
3318 
3319  /**
3320  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3321  * decoding (if active).
3322  * - encoding: unused
3323  * - decoding: Set by user (either before avcodec_open2(), or in the
3324  * AVCodecContext.get_format callback)
3325  */
3327 
3328  /**
3329  * Video decoding only. Certain video codecs support cropping, meaning that
3330  * only a sub-rectangle of the decoded frame is intended for display. This
3331  * option controls how cropping is handled by libavcodec.
3332  *
3333  * When set to 1 (the default), libavcodec will apply cropping internally.
3334  * I.e. it will modify the output frame width/height fields and offset the
3335  * data pointers (only by as much as possible while preserving alignment, or
3336  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3337  * the frames output by the decoder refer only to the cropped area. The
3338  * crop_* fields of the output frames will be zero.
3339  *
3340  * When set to 0, the width/height fields of the output frames will be set
3341  * to the coded dimensions and the crop_* fields will describe the cropping
3342  * rectangle. Applying the cropping is left to the caller.
3343  *
3344  * @warning When hardware acceleration with opaque output frames is used,
3345  * libavcodec is unable to apply cropping from the top/left border.
3346  *
3347  * @note when this option is set to zero, the width/height fields of the
3348  * AVCodecContext and output AVFrames have different meanings. The codec
3349  * context fields store display dimensions (with the coded dimensions in
3350  * coded_width/height), while the frame fields store the coded dimensions
3351  * (with the display dimensions being determined by the crop_* fields).
3352  */
3354 
3355  /*
3356  * Video decoding only. Sets the number of extra hardware frames which
3357  * the decoder will allocate for use by the caller. This must be set
3358  * before avcodec_open2() is called.
3359  *
3360  * Some hardware decoders require all frames that they will use for
3361  * output to be defined in advance before decoding starts. For such
3362  * decoders, the hardware frame pool must therefore be of a fixed size.
3363  * The extra frames set here are on top of any number that the decoder
3364  * needs internally in order to operate normally (for example, frames
3365  * used as reference pictures).
3366  */
3368 
3369  /**
3370  * The percentage of damaged samples to discard a frame.
3371  *
3372  * - decoding: set by user
3373  * - encoding: unused
3374  */
3376 
3377  /**
3378  * The number of samples per frame to maximally accept.
3379  *
3380  * - decoding: set by user
3381  * - encoding: set by user
3382  */
3383  int64_t max_samples;
3384 } AVCodecContext;
3385 
3386 #if FF_API_CODEC_GET_SET
3387 /**
3388  * Accessors for some AVCodecContext fields. These used to be provided for ABI
3389  * compatibility, and do not need to be used anymore.
3390  */
3395 
3400 
3402 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3403 
3404 #if FF_API_LOWRES
3406 int av_codec_get_lowres(const AVCodecContext *avctx);
3408 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3409 #endif
3410 
3412 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3414 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3415 
3417 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3419 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3420 #endif
3421 
3422 /**
3423  * AVProfile.
3424  */
3425 typedef struct AVProfile {
3426  int profile;
3427  const char *name; ///< short name for the profile
3428 } AVProfile;
3429 
3430 enum {
3431  /**
3432  * The codec supports this format via the hw_device_ctx interface.
3433  *
3434  * When selecting this format, AVCodecContext.hw_device_ctx should
3435  * have been set to a device of the specified type before calling
3436  * avcodec_open2().
3437  */
3439  /**
3440  * The codec supports this format via the hw_frames_ctx interface.
3441  *
3442  * When selecting this format for a decoder,
3443  * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3444  * context inside the get_format() callback. The frames context
3445  * must have been created on a device of the specified type.
3446  */
3448  /**
3449  * The codec supports this format by some internal method.
3450  *
3451  * This format can be selected without any additional configuration -
3452  * no device or frames context is required.
3453  */
3455  /**
3456  * The codec supports this format by some ad-hoc method.
3457  *
3458  * Additional settings and/or function calls are required. See the
3459  * codec-specific documentation for details. (Methods requiring
3460  * this sort of configuration are deprecated and others should be
3461  * used in preference.)
3462  */
3464 };
3465 
3466 typedef struct AVCodecHWConfig {
3467  /**
3468  * A hardware pixel format which the codec can use.
3469  */
3471  /**
3472  * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3473  * setup methods which can be used with this configuration.
3474  */
3475  int methods;
3476  /**
3477  * The device type associated with the configuration.
3478  *
3479  * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3480  * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3481  */
3483 } AVCodecHWConfig;
3484 
3485 typedef struct AVCodecDefault AVCodecDefault;
3486 
3487 struct AVSubtitle;
3488 
3489 /**
3490  * AVCodec.
3491  */
3492 typedef struct AVCodec {
3493  /**
3494  * Name of the codec implementation.
3495  * The name is globally unique among encoders and among decoders (but an
3496  * encoder and a decoder can share the same name).
3497  * This is the primary way to find a codec from the user perspective.
3498  */
3499  const char *name;
3500  /**
3501  * Descriptive name for the codec, meant to be more human readable than name.
3502  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3503  */
3504  const char *long_name;
3507  /**
3508  * Codec capabilities.
3509  * see AV_CODEC_CAP_*
3510  */
3512  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3513  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3514  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3515  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3516  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3517  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3518  const AVClass *priv_class; ///< AVClass for the private context
3519  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3520 
3521  /**
3522  * Group name of the codec implementation.
3523  * This is a short symbolic name of the wrapper backing this codec. A
3524  * wrapper uses some kind of external implementation for the codec, such
3525  * as an external library, or a codec implementation provided by the OS or
3526  * the hardware.
3527  * If this field is NULL, this is a builtin, libavcodec native codec.
3528  * If non-NULL, this will be the suffix in AVCodec.name in most cases
3529  * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
3530  */
3531  const char *wrapper_name;
3532 
3533  /*****************************************************************
3534  * No fields below this line are part of the public API. They
3535  * may not be used outside of libavcodec and can be changed and
3536  * removed at will.
3537  * New public fields should be added right above.
3538  *****************************************************************
3539  */
3541  struct AVCodec *next;
3542  /**
3543  * @name Frame-level threading support functions
3544  * @{
3545  */
3546  /**
3547  * If defined, called on thread contexts when they are created.
3548  * If the codec allocates writable tables in init(), re-allocate them here.
3549  * priv_data will be set to a copy of the original.
3550  */
3552  /**
3553  * Copy necessary context variables from a previous thread context to the current one.
3554  * If not defined, the next thread will start automatically; otherwise, the codec
3555  * must call ff_thread_finish_setup().
3556  *
3557  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3558  */
3560  /** @} */
3561 
3562  /**
3563  * Private codec-specific defaults.
3564  */
3566 
3567  /**
3568  * Initialize codec static data, called from avcodec_register().
3569  *
3570  * This is not intended for time consuming operations as it is
3571  * run for every codec regardless of that codec being used.
3572  */
3573  void (*init_static_data)(struct AVCodec *codec);
3574 
3576  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3577  const struct AVSubtitle *sub);
3578  /**
3579  * Encode data to an AVPacket.
3580  *
3581  * @param avctx codec context
3582  * @param avpkt output AVPacket (may contain a user-provided buffer)
3583  * @param[in] frame AVFrame containing the raw data to be encoded
3584  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3585  * non-empty packet was returned in avpkt.
3586  * @return 0 on success, negative error code on failure
3587  */
3588  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3589  int *got_packet_ptr);
3590  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3591  int (*close)(AVCodecContext *);
3592  /**
3593  * Encode API with decoupled packet/frame dataflow. The API is the
3594  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3595  * that:
3596  * - never called if the codec is closed or the wrong type,
3597  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3598  * - only one drain frame is ever passed down,
3599  */
3600  int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3601  int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3602 
3603  /**
3604  * Decode API with decoupled packet/frame dataflow. This function is called
3605  * to get one output frame. It should call ff_decode_get_packet() to obtain
3606  * input data.
3607  */
3609  /**
3610  * Flush buffers.
3611  * Will be called when seeking
3612  */
3614  /**
3615  * Internal codec capabilities.
3616  * See FF_CODEC_CAP_* in internal.h
3617  */
3619 
3620  /**
3621  * Decoding only, a comma-separated list of bitstream filters to apply to
3622  * packets before decoding.
3623  */
3624  const char *bsfs;
3625 
3626  /**
3627  * Array of pointers to hardware configurations supported by the codec,
3628  * or NULL if no hardware supported. The array is terminated by a NULL
3629  * pointer.
3630  *
3631  * The user can only access this field via avcodec_get_hw_config().
3632  */
3634 } AVCodec;
3635 
3636 #if FF_API_CODEC_GET_SET
3638 int av_codec_get_max_lowres(const AVCodec *codec);
3639 #endif
3640 
3641 struct MpegEncContext;
3642 
3643 /**
3644  * Retrieve supported hardware configurations for a codec.
3645  *
3646  * Values of index from zero to some maximum return the indexed configuration
3647  * descriptor; all other values return NULL. If the codec does not support
3648  * any hardware configurations then it will always return NULL.
3649  */
3650 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3651 
3652 /**
3653  * @defgroup lavc_hwaccel AVHWAccel
3654  *
3655  * @note Nothing in this structure should be accessed by the user. At some
3656  * point in future it will not be externally visible at all.
3657  *
3658  * @{
3659  */
3660 typedef struct AVHWAccel {
3661  /**
3662  * Name of the hardware accelerated codec.
3663  * The name is globally unique among encoders and among decoders (but an
3664  * encoder and a decoder can share the same name).
3665  */
3666  const char *name;
3667 
3668  /**
3669  * Type of codec implemented by the hardware accelerator.
3670  *
3671  * See AVMEDIA_TYPE_xxx
3672  */
3674 
3675  /**
3676  * Codec implemented by the hardware accelerator.
3677  *
3678  * See AV_CODEC_ID_xxx
3679  */
3681 
3682  /**
3683  * Supported pixel format.
3684  *
3685  * Only hardware accelerated formats are supported here.
3686  */
3688 
3689  /**
3690  * Hardware accelerated codec capabilities.
3691  * see AV_HWACCEL_CODEC_CAP_*
3692  */
3694 
3695  /*****************************************************************
3696  * No fields below this line are part of the public API. They
3697  * may not be used outside of libavcodec and can be changed and
3698  * removed at will.
3699  * New public fields should be added right above.
3700  *****************************************************************
3701  */
3702 
3703  /**
3704  * Allocate a custom buffer
3705  */
3707 
3708  /**
3709  * Called at the beginning of each frame or field picture.
3710  *
3711  * Meaningful frame information (codec specific) is guaranteed to
3712  * be parsed at this point. This function is mandatory.
3713  *
3714  * Note that buf can be NULL along with buf_size set to 0.
3715  * Otherwise, this means the whole frame is available at this point.
3716  *
3717  * @param avctx the codec context
3718  * @param buf the frame data buffer base
3719  * @param buf_size the size of the frame in bytes
3720  * @return zero if successful, a negative value otherwise
3721  */
3722  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3723 
3724  /**
3725  * Callback for parameter data (SPS/PPS/VPS etc).
3726  *
3727  * Useful for hardware decoders which keep persistent state about the
3728  * video parameters, and need to receive any changes to update that state.
3729  *
3730  * @param avctx the codec context
3731  * @param type the nal unit type
3732  * @param buf the nal unit data buffer
3733  * @param buf_size the size of the nal unit in bytes
3734  * @return zero if successful, a negative value otherwise
3735  */
3736  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3737 
3738  /**
3739  * Callback for each slice.
3740  *
3741  * Meaningful slice information (codec specific) is guaranteed to
3742  * be parsed at this point. This function is mandatory.
3743  * The only exception is XvMC, that works on MB level.
3744  *
3745  * @param avctx the codec context
3746  * @param buf the slice data buffer base
3747  * @param buf_size the size of the slice in bytes
3748  * @return zero if successful, a negative value otherwise
3749  */
3750  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3751 
3752  /**
3753  * Called at the end of each frame or field picture.
3754  *
3755  * The whole picture is parsed at this point and can now be sent
3756  * to the hardware accelerator. This function is mandatory.
3757  *
3758  * @param avctx the codec context
3759  * @return zero if successful, a negative value otherwise
3760  */
3761  int (*end_frame)(AVCodecContext *avctx);
3762 
3763  /**
3764  * Size of per-frame hardware accelerator private data.
3765  *
3766  * Private data is allocated with av_mallocz() before
3767  * AVCodecContext.get_buffer() and deallocated after
3768  * AVCodecContext.release_buffer().
3769  */
3771 
3772  /**
3773  * Called for every Macroblock in a slice.
3774  *
3775  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3776  * Instead of decoding to raw picture, MB parameters are
3777  * stored in an array provided by the video driver.
3778  *
3779  * @param s the mpeg context
3780  */
3782 
3783  /**
3784  * Initialize the hwaccel private data.
3785  *
3786  * This will be called from ff_get_format(), after hwaccel and
3787  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3788  * is allocated.
3789  */
3791 
3792  /**
3793  * Uninitialize the hwaccel private data.
3794  *
3795  * This will be called from get_format() or avcodec_close(), after hwaccel
3796  * and hwaccel_context are already uninitialized.
3797  */
3799 
3800  /**
3801  * Size of the private data to allocate in
3802  * AVCodecInternal.hwaccel_priv_data.
3803  */
3805 
3806  /**
3807  * Internal hwaccel capabilities.
3808  */
3810 
3811  /**
3812  * Fill the given hw_frames context with current codec parameters. Called
3813  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3814  * details.
3815  *
3816  * This CAN be called before AVHWAccel.init is called, and you must assume
3817  * that avctx->hwaccel_priv_data is invalid.
3818  */
3819  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
3820 } AVHWAccel;
3821 
3822 /**
3823  * HWAccel is experimental and is thus avoided in favor of non experimental
3824  * codecs
3825  */
3826 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3827 
3828 /**
3829  * Hardware acceleration should be used for decoding even if the codec level
3830  * used is unknown or higher than the maximum supported level reported by the
3831  * hardware driver.
3832  *
3833  * It's generally a good idea to pass this flag unless you have a specific
3834  * reason not to, as hardware tends to under-report supported levels.
3835  */
3836 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3837 
3838 /**
3839  * Hardware acceleration can output YUV pixel formats with a different chroma
3840  * sampling than 4:2:0 and/or other than 8 bits per component.
3841  */
3842 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3843 
3844 /**
3845  * Hardware acceleration should still be attempted for decoding when the
3846  * codec profile does not match the reported capabilities of the hardware.
3847  *
3848  * For example, this can be used to try to decode baseline profile H.264
3849  * streams in hardware - it will often succeed, because many streams marked
3850  * as baseline profile actually conform to constrained baseline profile.
3851  *
3852  * @warning If the stream is actually not supported then the behaviour is
3853  * undefined, and may include returning entirely incorrect output
3854  * while indicating success.
3855  */
3856 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3857 
3858 /**
3859  * @}
3860  */
3861 
3862 #if FF_API_AVPICTURE
3863 /**
3864  * @defgroup lavc_picture AVPicture
3865  *
3866  * Functions for working with AVPicture
3867  * @{
3868  */
3869 
3870 /**
3871  * Picture data structure.
3872  *
3873  * Up to four components can be stored into it, the last component is
3874  * alpha.
3875  * @deprecated use AVFrame or imgutils functions instead
3876  */
3877 typedef struct AVPicture {
3879  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3881  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3882 } AVPicture;
3883 
3884 /**
3885  * @}
3886  */
3887 #endif
3888 
3891 
3892  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3893 
3894  /**
3895  * Plain text, the text field must be set by the decoder and is
3896  * authoritative. ass and pict fields may contain approximations.
3897  */
3899 
3900  /**
3901  * Formatted text, the ass field must be set by the decoder and is
3902  * authoritative. pict and text fields may contain approximations.
3903  */
3905 };
3906 
3907 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3908 
3909 typedef struct AVSubtitleRect {
3910  int x; ///< top left corner of pict, undefined when pict is not set
3911  int y; ///< top left corner of pict, undefined when pict is not set
3912  int w; ///< width of pict, undefined when pict is not set
3913  int h; ///< height of pict, undefined when pict is not set
3914  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3915 
3916 #if FF_API_AVPICTURE
3917  /**
3918  * @deprecated unused
3919  */
3922 #endif
3923  /**
3924  * data+linesize for the bitmap of this subtitle.
3925  * Can be set for text/ass as well once they are rendered.
3926  */
3928  int linesize[4];
3929 
3931 
3932  char *text; ///< 0 terminated plain UTF-8 text
3933 
3934  /**
3935  * 0 terminated ASS/SSA compatible event line.
3936  * The presentation of this is unaffected by the other values in this
3937  * struct.
3938  */
3939  char *ass;
3940 
3941  int flags;
3942 } AVSubtitleRect;
3943 
3944 typedef struct AVSubtitle {
3945  uint16_t format; /* 0 = graphics */
3946  uint32_t start_display_time; /* relative to packet pts, in ms */
3947  uint32_t end_display_time; /* relative to packet pts, in ms */
3948  unsigned num_rects;
3950  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3951 } AVSubtitle;
3952 
3953 /**
3954  * This struct describes the properties of an encoded stream.
3955  *
3956  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3957  * be allocated with avcodec_parameters_alloc() and freed with
3958  * avcodec_parameters_free().
3959  */
3960 typedef struct AVCodecParameters {
3961  /**
3962  * General type of the encoded data.
3963  */
3965  /**
3966  * Specific type of the encoded data (the codec used).
3967  */
3969  /**
3970  * Additional information about the codec (corresponds to the AVI FOURCC).
3971  */
3972  uint32_t codec_tag;
3973 
3974  /**
3975  * Extra binary data needed for initializing the decoder, codec-dependent.
3976  *
3977  * Must be allocated with av_malloc() and will be freed by
3978  * avcodec_parameters_free(). The allocated size of extradata must be at
3979  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3980  * bytes zeroed.
3981  */
3983  /**
3984  * Size of the extradata content in bytes.
3985  */
3987 
3988  /**
3989  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3990  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3991  */
3992  int format;
3993 
3994  /**
3995  * The average bitrate of the encoded data (in bits per second).
3996  */
3997  int64_t bit_rate;
3998 
3999  /**
4000  * The number of bits per sample in the codedwords.
4001  *
4002  * This is basically the bitrate per sample. It is mandatory for a bunch of
4003  * formats to actually decode them. It's the number of bits for one sample in
4004  * the actual coded bitstream.
4005  *
4006  * This could be for example 4 for ADPCM
4007  * For PCM formats this matches bits_per_raw_sample
4008  * Can be 0
4009  */
4011 
4012  /**
4013  * This is the number of valid bits in each output sample. If the
4014  * sample format has more bits, the least significant bits are additional
4015  * padding bits, which are always 0. Use right shifts to reduce the sample
4016  * to its actual size. For example, audio formats with 24 bit samples will
4017  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
4018  * To get the original sample use "(int32_t)sample >> 8"."
4019  *
4020  * For ADPCM this might be 12 or 16 or similar
4021  * Can be 0
4022  */
4024 
4025  /**
4026  * Codec-specific bitstream restrictions that the stream conforms to.
4027  */
4028  int profile;
4029  int level;
4030 
4031  /**
4032  * Video only. The dimensions of the video frame in pixels.
4033  */
4034  int width;
4035  int height;
4036 
4037  /**
4038  * Video only. The aspect ratio (width / height) which a single pixel
4039  * should have when displayed.
4040  *
4041  * When the aspect ratio is unknown / undefined, the numerator should be
4042  * set to 0 (the denominator may have any value).
4043  */
4045 
4046  /**
4047  * Video only. The order of the fields in interlaced video.
4048  */
4049  enum AVFieldOrder field_order;
4050 
4051  /**
4052  * Video only. Additional colorspace characteristics.
4053  */
4057  enum AVColorSpace color_space;
4058  enum AVChromaLocation chroma_location;
4059 
4060  /**
4061  * Video only. Number of delayed frames.
4062  */
4064 
4065  /**
4066  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4067  * unknown or unspecified, otherwise the number of bits set must be equal to
4068  * the channels field.
4069  */
4070  uint64_t channel_layout;
4071  /**
4072  * Audio only. The number of audio channels.
4073  */
4075  /**
4076  * Audio only. The number of audio samples per second.
4077  */
4079  /**
4080  * Audio only. The number of bytes per coded audio frame, required by some
4081  * formats.
4082  *
4083  * Corresponds to nBlockAlign in WAVEFORMATEX.
4084  */
4086  /**
4087  * Audio only. Audio frame size, if known. Required by some formats to be static.
4088  */
4090 
4091  /**
4092  * Audio only. The amount of padding (in samples) inserted by the encoder at
4093  * the beginning of the audio. I.e. this number of leading decoded samples
4094  * must be discarded by the caller to get the original audio without leading
4095  * padding.
4096  */
4098  /**
4099  * Audio only. The amount of padding (in samples) appended by the encoder to
4100  * the end of the audio. I.e. this number of decoded samples must be
4101  * discarded by the caller from the end of the stream to get the original
4102  * audio without any trailing padding.
4103  */
4105  /**
4106  * Audio only. Number of samples to skip after a discontinuity.
4107  */
4110 
4111 /**
4112  * Iterate over all registered codecs.
4113  *
4114  * @param opaque a pointer where libavcodec will store the iteration state. Must
4115  * point to NULL to start the iteration.
4116  *
4117  * @return the next registered codec or NULL when the iteration is
4118  * finished
4119  */
4120 const AVCodec *av_codec_iterate(void **opaque);
4121 
4122 #if FF_API_NEXT
4123 /**
4124  * If c is NULL, returns the first registered codec,
4125  * if c is non-NULL, returns the next registered codec after c,
4126  * or NULL if c is the last one.
4127  */
4129 AVCodec *av_codec_next(const AVCodec *c);
4130 #endif
4131 
4132 /**
4133  * Return the LIBAVCODEC_VERSION_INT constant.
4134  */
4135 unsigned avcodec_version(void);
4136 
4137 /**
4138  * Return the libavcodec build-time configuration.
4139  */
4140 const char *avcodec_configuration(void);
4141 
4142 /**
4143  * Return the libavcodec license.
4144  */
4145 const char *avcodec_license(void);
4146 
4147 #if FF_API_NEXT
4148 /**
4149  * Register the codec codec and initialize libavcodec.
4150  *
4151  * @warning either this function or avcodec_register_all() must be called
4152  * before any other libavcodec functions.
4153  *
4154  * @see avcodec_register_all()
4155  */
4157 void avcodec_register(AVCodec *codec);
4158 
4159 /**
4160  * Register all the codecs, parsers and bitstream filters which were enabled at
4161  * configuration time. If you do not call this function you can select exactly
4162  * which formats you want to support, by using the individual registration
4163  * functions.
4164  *
4165  * @see avcodec_register
4166  * @see av_register_codec_parser
4167  * @see av_register_bitstream_filter
4168  */
4170 void avcodec_register_all(void);
4171 #endif
4172 
4173 /**
4174  * Allocate an AVCodecContext and set its fields to default values. The
4175  * resulting struct should be freed with avcodec_free_context().
4176  *
4177  * @param codec if non-NULL, allocate private data and initialize defaults
4178  * for the given codec. It is illegal to then call avcodec_open2()
4179  * with a different codec.
4180  * If NULL, then the codec-specific defaults won't be initialized,
4181  * which may result in suboptimal default settings (this is
4182  * important mainly for encoders, e.g. libx264).
4183  *
4184  * @return An AVCodecContext filled with default values or NULL on failure.
4185  */
4187 
4188 /**
4189  * Free the codec context and everything associated with it and write NULL to
4190  * the provided pointer.
4191  */
4192 void avcodec_free_context(AVCodecContext **avctx);
4193 
4194 #if FF_API_GET_CONTEXT_DEFAULTS
4195 /**
4196  * @deprecated This function should not be used, as closing and opening a codec
4197  * context multiple time is not supported. A new codec context should be
4198  * allocated for each new use.
4199  */
4201 #endif
4202 
4203 /**
4204  * Get the AVClass for AVCodecContext. It can be used in combination with
4205  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4206  *
4207  * @see av_opt_find().
4208  */
4209 const AVClass *avcodec_get_class(void);
4210 
4211 #if FF_API_COPY_CONTEXT
4212 /**
4213  * Get the AVClass for AVFrame. It can be used in combination with
4214  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4215  *
4216  * @see av_opt_find().
4217  */
4218 const AVClass *avcodec_get_frame_class(void);
4219 
4220 /**
4221  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4222  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4223  *
4224  * @see av_opt_find().
4225  */
4227 
4228 /**
4229  * Copy the settings of the source AVCodecContext into the destination
4230  * AVCodecContext. The resulting destination codec context will be
4231  * unopened, i.e. you are required to call avcodec_open2() before you
4232  * can use this AVCodecContext to decode/encode video/audio data.
4233  *
4234  * @param dest target codec context, should be initialized with
4235  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4236  * @param src source codec context
4237  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4238  *
4239  * @deprecated The semantics of this function are ill-defined and it should not
4240  * be used. If you need to transfer the stream parameters from one codec context
4241  * to another, use an intermediate AVCodecParameters instance and the
4242  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4243  * functions.
4244  */
4247 #endif
4248 
4249 /**
4250  * Allocate a new AVCodecParameters and set its fields to default values
4251  * (unknown/invalid/0). The returned struct must be freed with
4252  * avcodec_parameters_free().
4253  */
4255 
4256 /**
4257  * Free an AVCodecParameters instance and everything associated with it and
4258  * write NULL to the supplied pointer.
4259  */
4261 
4262 /**
4263  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4264  * replaced with newly allocated duplicates of the corresponding fields in src.
4265  *
4266  * @return >= 0 on success, a negative AVERROR code on failure.
4267  */
4269 
4270 /**
4271  * Fill the parameters struct based on the values from the supplied codec
4272  * context. Any allocated fields in par are freed and replaced with duplicates
4273  * of the corresponding fields in codec.
4274  *
4275  * @return >= 0 on success, a negative AVERROR code on failure
4276  */
4278  const AVCodecContext *codec);
4279 
4280 /**
4281  * Fill the codec context based on the values from the supplied codec
4282  * parameters. Any allocated fields in codec that have a corresponding field in
4283  * par are freed and replaced with duplicates of the corresponding field in par.
4284  * Fields in codec that do not have a counterpart in par are not touched.
4285  *
4286  * @return >= 0 on success, a negative AVERROR code on failure.
4287  */
4289  const AVCodecParameters *par);
4290 
4291 /**
4292  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4293  * function the context has to be allocated with avcodec_alloc_context3().
4294  *
4295  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4296  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4297  * retrieving a codec.
4298  *
4299  * @warning This function is not thread safe!
4300  *
4301  * @note Always call this function before using decoding routines (such as
4302  * @ref avcodec_receive_frame()).
4303  *
4304  * @code
4305  * avcodec_register_all();
4306  * av_dict_set(&opts, "b", "2.5M", 0);
4307  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4308  * if (!codec)
4309  * exit(1);
4310  *
4311  * context = avcodec_alloc_context3(codec);
4312  *
4313  * if (avcodec_open2(context, codec, opts) < 0)
4314  * exit(1);
4315  * @endcode
4316  *
4317  * @param avctx The context to initialize.
4318  * @param codec The codec to open this context for. If a non-NULL codec has been
4319  * previously passed to avcodec_alloc_context3() or
4320  * for this context, then this parameter MUST be either NULL or
4321  * equal to the previously passed codec.
4322  * @param options A dictionary filled with AVCodecContext and codec-private options.
4323  * On return this object will be filled with options that were not found.
4324  *
4325  * @return zero on success, a negative value on error
4326  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4327  * av_dict_set(), av_opt_find().
4328  */
4329 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4330 
4331 /**
4332  * Close a given AVCodecContext and free all the data associated with it
4333  * (but not the AVCodecContext itself).
4334  *
4335  * Calling this function on an AVCodecContext that hasn't been opened will free
4336  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4337  * codec. Subsequent calls will do nothing.
4338  *
4339  * @note Do not use this function. Use avcodec_free_context() to destroy a
4340  * codec context (either open or closed). Opening and closing a codec context
4341  * multiple times is not supported anymore -- use multiple codec contexts
4342  * instead.
4343  */
4344 int avcodec_close(AVCodecContext *avctx);
4345 
4346 /**
4347  * Free all allocated data in the given subtitle struct.
4348  *
4349  * @param sub AVSubtitle to free.
4350  */
4351 void avsubtitle_free(AVSubtitle *sub);
4352 
4353 /**
4354  * @}
4355  */
4356 
4357 /**
4358  * @addtogroup lavc_packet
4359  * @{
4360  */
4361 
4362 /**
4363  * Allocate an AVPacket and set its fields to default values. The resulting
4364  * struct must be freed using av_packet_free().
4365  *
4366  * @return An AVPacket filled with default values or NULL on failure.
4367  *
4368  * @note this only allocates the AVPacket itself, not the data buffers. Those
4369  * must be allocated through other means such as av_new_packet.
4370  *
4371  * @see av_new_packet
4372  */
4373 AVPacket *av_packet_alloc(void);
4374 
4375 /**
4376  * Create a new packet that references the same data as src.
4377  *
4378  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4379  *
4380  * @return newly created AVPacket on success, NULL on error.
4381  *
4382  * @see av_packet_alloc
4383  * @see av_packet_ref
4384  */
4386 
4387 /**
4388  * Free the packet, if the packet is reference counted, it will be
4389  * unreferenced first.
4390  *
4391  * @param pkt packet to be freed. The pointer will be set to NULL.
4392  * @note passing NULL is a no-op.
4393  */
4394 void av_packet_free(AVPacket **pkt);
4395 
4396 /**
4397  * Initialize optional fields of a packet with default values.
4398  *
4399  * Note, this does not touch the data and size members, which have to be
4400  * initialized separately.
4401  *
4402  * @param pkt packet
4403  */
4404 void av_init_packet(AVPacket *pkt);
4405 
4406 /**
4407  * Allocate the payload of a packet and initialize its fields with
4408  * default values.
4409  *
4410  * @param pkt packet
4411  * @param size wanted payload size
4412  * @return 0 if OK, AVERROR_xxx otherwise
4413  */
4414 int av_new_packet(AVPacket *pkt, int size);
4415 
4416 /**
4417  * Reduce packet size, correctly zeroing padding
4418  *
4419  * @param pkt packet
4420  * @param size new size
4421  */
4422 void av_shrink_packet(AVPacket *pkt, int size);
4423 
4424 /**
4425  * Increase packet size, correctly zeroing padding
4426  *
4427  * @param pkt packet
4428  * @param grow_by number of bytes by which to increase the size of the packet
4429  */
4430 int av_grow_packet(AVPacket *pkt, int grow_by);
4431 
4432 /**
4433  * Initialize a reference-counted packet from av_malloc()ed data.
4434  *
4435  * @param pkt packet to be initialized. This function will set the data, size,
4436  * and buf fields, all others are left untouched.
4437  * @param data Data allocated by av_malloc() to be used as packet data. If this
4438  * function returns successfully, the data is owned by the underlying AVBuffer.
4439  * The caller may not access the data through other means.
4440  * @param size size of data in bytes, without the padding. I.e. the full buffer
4441  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4442  *
4443  * @return 0 on success, a negative AVERROR on error
4444  */
4446 
4447 #if FF_API_AVPACKET_OLD_API
4448 /**
4449  * @warning This is a hack - the packet memory allocation stuff is broken. The
4450  * packet is allocated if it was not really allocated.
4451  *
4452  * @deprecated Use av_packet_ref or av_packet_make_refcounted
4453  */
4455 int av_dup_packet(AVPacket *pkt);
4456 /**
4457  * Copy packet, including contents
4458  *
4459  * @return 0 on success, negative AVERROR on fail
4460  *
4461  * @deprecated Use av_packet_ref
4462  */
4464 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4465 
4466 /**
4467  * Copy packet side data
4468  *
4469  * @return 0 on success, negative AVERROR on fail
4470  *
4471  * @deprecated Use av_packet_copy_props
4472  */
4474 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4475 
4476 /**
4477  * Free a packet.
4478  *
4479  * @deprecated Use av_packet_unref
4480  *
4481  * @param pkt packet to free
4482  */
4484 void av_free_packet(AVPacket *pkt);
4485 #endif
4486 /**
4487  * Allocate new information of a packet.
4488  *
4489  * @param pkt packet
4490  * @param type side information type
4491  * @param size side information size
4492  * @return pointer to fresh allocated data or NULL otherwise
4493  */
4495  int size);
4496 
4497 /**
4498  * Wrap an existing array as a packet side data.
4499  *
4500  * @param pkt packet
4501  * @param type side information type
4502  * @param data the side data array. It must be allocated with the av_malloc()
4503  * family of functions. The ownership of the data is transferred to
4504  * pkt.
4505  * @param size side information size
4506  * @return a non-negative number on success, a negative AVERROR code on
4507  * failure. On failure, the packet is unchanged and the data remains
4508  * owned by the caller.
4509  */
4511  uint8_t *data, size_t size);
4512 
4513 /**
4514  * Shrink the already allocated side data buffer
4515  *
4516  * @param pkt packet
4517  * @param type side information type
4518  * @param size new side information size
4519  * @return 0 on success, < 0 on failure
4520  */
4522  int size);
4523 
4524 /**
4525  * Get side information from packet.
4526  *
4527  * @param pkt packet
4528  * @param type desired side information type
4529  * @param size pointer for side information size to store (optional)
4530  * @return pointer to data if present or NULL otherwise
4531  */
4533  int *size);
4534 
4535 #if FF_API_MERGE_SD_API
4538 
4541 #endif
4542 
4544 
4545 /**
4546  * Pack a dictionary for use in side_data.
4547  *
4548  * @param dict The dictionary to pack.
4549  * @param size pointer to store the size of the returned data
4550  * @return pointer to data if successful, NULL otherwise
4551  */
4553 /**
4554  * Unpack a dictionary from side_data.
4555  *
4556  * @param data data from side_data
4557  * @param size size of the data
4558  * @param dict the metadata storage dictionary
4559  * @return 0 on success, < 0 on failure
4560  */
4561 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4562 
4563 
4564 /**
4565  * Convenience function to free all the side data stored.
4566  * All the other fields stay untouched.
4567  *
4568  * @param pkt packet
4569  */
4571 
4572 /**
4573  * Setup a new reference to the data described by a given packet
4574  *
4575  * If src is reference-counted, setup dst as a new reference to the
4576  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4577  * data from src into it.
4578  *
4579  * All the other fields are copied from src.
4580  *
4581  * @see av_packet_unref
4582  *
4583  * @param dst Destination packet
4584  * @param src Source packet
4585  *
4586  * @return 0 on success, a negative AVERROR on error.
4587  */
4588 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4589 
4590 /**
4591  * Wipe the packet.
4592  *
4593  * Unreference the buffer referenced by the packet and reset the
4594  * remaining packet fields to their default values.
4595  *
4596  * @param pkt The packet to be unreferenced.
4597  */
4599 
4600 /**
4601  * Move every field in src to dst and reset src.
4602  *
4603  * @see av_packet_unref
4604  *
4605  * @param src Source packet, will be reset
4606  * @param dst Destination packet
4607  */
4609 
4610 /**
4611  * Copy only "properties" fields from src to dst.
4612  *
4613  * Properties for the purpose of this function are all the fields
4614  * beside those related to the packet data (buf, data, size)
4615  *
4616  * @param dst Destination packet
4617  * @param src Source packet
4618  *
4619  * @return 0 on success AVERROR on failure.
4620  */
4621 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4622 
4623 /**
4624  * Ensure the data described by a given packet is reference counted.
4625  *
4626  * @note This function does not ensure that the reference will be writable.
4627  * Use av_packet_make_writable instead for that purpose.
4628  *
4629  * @see av_packet_ref
4630  * @see av_packet_make_writable
4631  *
4632  * @param pkt packet whose data should be made reference counted.
4633  *
4634  * @return 0 on success, a negative AVERROR on error. On failure, the
4635  * packet is unchanged.
4636  */
4638 
4639 /**
4640  * Create a writable reference for the data described by a given packet,
4641  * avoiding data copy if possible.
4642  *
4643  * @param pkt Packet whose data should be made writable.
4644  *
4645  * @return 0 on success, a negative AVERROR on failure. On failure, the
4646  * packet is unchanged.
4647  */
4649 
4650 /**
4651  * Convert valid timing fields (timestamps / durations) in a packet from one
4652  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4653  * ignored.
4654  *
4655  * @param pkt packet on which the conversion will be performed
4656  * @param tb_src source timebase, in which the timing fields in pkt are
4657  * expressed
4658  * @param tb_dst destination timebase, to which the timing fields will be
4659  * converted
4660  */
4661 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4662 
4663 /**
4664  * @}
4665  */
4666 
4667 /**
4668  * @addtogroup lavc_decoding
4669  * @{
4670  */
4671 
4672 /**
4673  * Find a registered decoder with a matching codec ID.
4674  *
4675  * @param id AVCodecID of the requested decoder
4676  * @return A decoder if one was found, NULL otherwise.
4677  */
4679 
4680 /**
4681  * Find a registered decoder with the specified name.
4682  *
4683  * @param name name of the requested decoder
4684  * @return A decoder if one was found, NULL otherwise.
4685  */
4687 
4688 /**
4689  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4690  * it can be called by custom get_buffer2() implementations for decoders without
4691  * AV_CODEC_CAP_DR1 set.
4692  */
4694 
4695 /**
4696  * Modify width and height values so that they will result in a memory
4697  * buffer that is acceptable for the codec if you do not use any horizontal
4698  * padding.
4699  *
4700  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4701  */
4703 
4704 /**
4705  * Modify width and height values so that they will result in a memory
4706  * buffer that is acceptable for the codec if you also ensure that all
4707  * line sizes are a multiple of the respective linesize_align[i].
4708  *
4709  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4710  */
4712  int linesize_align[AV_NUM_DATA_POINTERS]);
4713 
4714 /**
4715  * Converts AVChromaLocation to swscale x/y chroma position.
4716  *
4717  * The positions represent the chroma (0,0) position in a coordinates system
4718  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4719  *
4720  * @param xpos horizontal chroma sample position
4721  * @param ypos vertical chroma sample position
4722  */
4723 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4724 
4725 /**
4726  * Converts swscale x/y chroma position to AVChromaLocation.
4727  *
4728  * The positions represent the chroma (0,0) position in a coordinates system
4729  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4730  *
4731  * @param xpos horizontal chroma sample position
4732  * @param ypos vertical chroma sample position
4733  */
4734 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4735 
4736 /**
4737  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4738  *
4739  * Some decoders may support multiple frames in a single AVPacket. Such
4740  * decoders would then just decode the first frame and the return value would be
4741  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4742  * called again with an AVPacket containing the remaining data in order to
4743  * decode the second frame, etc... Even if no frames are returned, the packet
4744  * needs to be fed to the decoder with remaining data until it is completely
4745  * consumed or an error occurs.
4746  *
4747  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4748  * and output. This means that for some packets they will not immediately
4749  * produce decoded output and need to be flushed at the end of decoding to get
4750  * all the decoded data. Flushing is done by calling this function with packets
4751  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4752  * returning samples. It is safe to flush even those decoders that are not
4753  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4754  *
4755  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4756  * larger than the actual read bytes because some optimized bitstream
4757  * readers read 32 or 64 bits at once and could read over the end.
4758  *
4759  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4760  * before packets may be fed to the decoder.
4761  *
4762  * @param avctx the codec context
4763  * @param[out] frame The AVFrame in which to store decoded audio samples.
4764  * The decoder will allocate a buffer for the decoded frame by
4765  * calling the AVCodecContext.get_buffer2() callback.
4766  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4767  * reference counted and the returned reference belongs to the
4768  * caller. The caller must release the frame using av_frame_unref()
4769  * when the frame is no longer needed. The caller may safely write
4770  * to the frame if av_frame_is_writable() returns 1.
4771  * When AVCodecContext.refcounted_frames is set to 0, the returned
4772  * reference belongs to the decoder and is valid only until the
4773  * next call to this function or until closing or flushing the
4774  * decoder. The caller may not write to it.
4775  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4776  * non-zero. Note that this field being set to zero
4777  * does not mean that an error has occurred. For
4778  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4779  * call is guaranteed to produce a frame.
4780  * @param[in] avpkt The input AVPacket containing the input buffer.
4781  * At least avpkt->data and avpkt->size should be set. Some
4782  * decoders might also require additional fields to be set.
4783  * @return A negative error code is returned if an error occurred during
4784  * decoding, otherwise the number of bytes consumed from the input
4785  * AVPacket is returned.
4786  *
4787 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4788  */
4791  int *got_frame_ptr, const AVPacket *avpkt);
4792 
4793 /**
4794  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4795  * Some decoders may support multiple frames in a single AVPacket, such
4796  * decoders would then just decode the first frame.
4797  *
4798  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4799  * the actual read bytes because some optimized bitstream readers read 32 or 64
4800  * bits at once and could read over the end.
4801  *
4802  * @warning The end of the input buffer buf should be set to 0 to ensure that
4803  * no overreading happens for damaged MPEG streams.
4804  *
4805  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4806  * between input and output, these need to be fed with avpkt->data=NULL,
4807  * avpkt->size=0 at the end to return the remaining frames.
4808  *
4809  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4810  * before packets may be fed to the decoder.
4811  *
4812  * @param avctx the codec context
4813  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4814  * Use av_frame_alloc() to get an AVFrame. The codec will
4815  * allocate memory for the actual bitmap by calling the
4816  * AVCodecContext.get_buffer2() callback.
4817  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4818  * reference counted and the returned reference belongs to the
4819  * caller. The caller must release the frame using av_frame_unref()
4820  * when the frame is no longer needed. The caller may safely write
4821  * to the frame if av_frame_is_writable() returns 1.
4822  * When AVCodecContext.refcounted_frames is set to 0, the returned
4823  * reference belongs to the decoder and is valid only until the
4824  * next call to this function or until closing or flushing the
4825  * decoder. The caller may not write to it.
4826  *
4827  * @param[in] avpkt The input AVPacket containing the input buffer.
4828  * You can create such packet with av_init_packet() and by then setting
4829  * data and size, some decoders might in addition need other fields like
4830  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4831  * fields possible.
4832  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4833  * @return On error a negative value is returned, otherwise the number of bytes
4834  * used or zero if no frame could be decompressed.
4835  *
4836  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4837  */
4839 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4840  int *got_picture_ptr,
4841  const AVPacket *avpkt);
4842 
4843 /**
4844  * Decode a subtitle message.
4845  * Return a negative value on error, otherwise return the number of bytes used.
4846  * If no subtitle could be decompressed, got_sub_ptr is zero.
4847  * Otherwise, the subtitle is stored in *sub.
4848  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4849  * simplicity, because the performance difference is expect to be negligible
4850  * and reusing a get_buffer written for video codecs would probably perform badly
4851  * due to a potentially very different allocation pattern.
4852  *
4853  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4854  * and output. This means that for some packets they will not immediately
4855  * produce decoded output and need to be flushed at the end of decoding to get
4856  * all the decoded data. Flushing is done by calling this function with packets
4857  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4858  * returning subtitles. It is safe to flush even those decoders that are not
4859  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4860  *
4861  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4862  * before packets may be fed to the decoder.
4863  *
4864  * @param avctx the codec context
4865  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4866  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4867  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4868  * @param[in] avpkt The input AVPacket containing the input buffer.
4869  */
4871  int *got_sub_ptr,
4872  AVPacket *avpkt);
4873 
4874 /**
4875  * Supply raw packet data as input to a decoder.
4876  *
4877  * Internally, this call will copy relevant AVCodecContext fields, which can
4878  * influence decoding per-packet, and apply them when the packet is actually
4879  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4880  * decoder to drop the frame contained by the packet sent with this function.)
4881  *
4882  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4883  * larger than the actual read bytes because some optimized bitstream
4884  * readers read 32 or 64 bits at once and could read over the end.
4885  *
4886  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4887  * on the same AVCodecContext. It will return unexpected results now
4888  * or in future libavcodec versions.
4889  *
4890  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4891  * before packets may be fed to the decoder.
4892  *
4893  * @param avctx codec context
4894  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4895  * frame, or several complete audio frames.
4896  * Ownership of the packet remains with the caller, and the
4897  * decoder will not write to the packet. The decoder may create
4898  * a reference to the packet data (or copy it if the packet is
4899  * not reference-counted).
4900  * Unlike with older APIs, the packet is always fully consumed,
4901  * and if it contains multiple frames (e.g. some audio codecs),
4902  * will require you to call avcodec_receive_frame() multiple
4903  * times afterwards before you can send a new packet.
4904  * It can be NULL (or an AVPacket with data set to NULL and
4905  * size set to 0); in this case, it is considered a flush
4906  * packet, which signals the end of the stream. Sending the
4907  * first flush packet will return success. Subsequent ones are
4908  * unnecessary and will return AVERROR_EOF. If the decoder
4909  * still has frames buffered, it will return them after sending
4910  * a flush packet.
4911  *
4912  * @return 0 on success, otherwise negative error code:
4913  * AVERROR(EAGAIN): input is not accepted in the current state - user
4914  * must read output with avcodec_receive_frame() (once
4915  * all output is read, the packet should be resent, and
4916  * the call will not fail with EAGAIN).
4917  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4918  * be sent to it (also returned if more than 1 flush
4919  * packet is sent)
4920  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4921  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4922  * other errors: legitimate decoding errors
4923  */
4924 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4925 
4926 /**
4927  * Return decoded output data from a decoder.
4928  *
4929  * @param avctx codec context
4930  * @param frame This will be set to a reference-counted video or audio
4931  * frame (depending on the decoder type) allocated by the
4932  * decoder. Note that the function will always call
4933  * av_frame_unref(frame) before doing anything else.
4934  *
4935  * @return
4936  * 0: success, a frame was returned
4937  * AVERROR(EAGAIN): output is not available in this state - user must try
4938  * to send new input
4939  * AVERROR_EOF: the decoder has been fully flushed, and there will be
4940  * no more output frames
4941  * AVERROR(EINVAL): codec not opened, or it is an encoder
4942  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
4943  * with respect to first decoded frame. Applicable
4944  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
4945  * other negative values: legitimate decoding errors
4946  */
4948 
4949 /**
4950  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4951  * to retrieve buffered output packets.
4952  *
4953  * @param avctx codec context
4954  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4955  * Ownership of the frame remains with the caller, and the
4956  * encoder will not write to the frame. The encoder may create
4957  * a reference to the frame data (or copy it if the frame is
4958  * not reference-counted).
4959  * It can be NULL, in which case it is considered a flush
4960  * packet. This signals the end of the stream. If the encoder
4961  * still has packets buffered, it will return them after this
4962  * call. Once flushing mode has been entered, additional flush
4963  * packets are ignored, and sending frames will return
4964  * AVERROR_EOF.
4965  *
4966  * For audio:
4967  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4968  * can have any number of samples.
4969  * If it is not set, frame->nb_samples must be equal to
4970  * avctx->frame_size for all frames except the last.
4971  * The final frame may be smaller than avctx->frame_size.
4972  * @return 0 on success, otherwise negative error code:
4973  * AVERROR(EAGAIN): input is not accepted in the current state - user
4974  * must read output with avcodec_receive_packet() (once
4975  * all output is read, the packet should be resent, and
4976  * the call will not fail with EAGAIN).
4977  * AVERROR_EOF: the encoder has been flushed, and no new frames can
4978  * be sent to it
4979  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4980  * decoder, or requires flush
4981  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4982  * other errors: legitimate decoding errors
4983  */
4984 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4985 
4986 /**
4987  * Read encoded data from the encoder.
4988  *
4989  * @param avctx codec context
4990  * @param avpkt This will be set to a reference-counted packet allocated by the
4991  * encoder. Note that the function will always call
4992  * av_frame_unref(frame) before doing anything else.
4993  * @return 0 on success, otherwise negative error code:
4994  * AVERROR(EAGAIN): output is not available in the current state - user
4995  * must try to send input
4996  * AVERROR_EOF: the encoder has been fully flushed, and there will be
4997  * no more output packets
4998  * AVERROR(EINVAL): codec not opened, or it is an encoder
4999  * other errors: legitimate decoding errors
5000  */
5001 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
5002 
5003 /**
5004  * Create and return a AVHWFramesContext with values adequate for hardware
5005  * decoding. This is meant to get called from the get_format callback, and is
5006  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
5007  * This API is for decoding with certain hardware acceleration modes/APIs only.
5008  *
5009  * The returned AVHWFramesContext is not initialized. The caller must do this
5010  * with av_hwframe_ctx_init().
5011  *
5012  * Calling this function is not a requirement, but makes it simpler to avoid
5013  * codec or hardware API specific details when manually allocating frames.
5014  *
5015  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
5016  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
5017  * it unnecessary to call this function or having to care about
5018  * AVHWFramesContext initialization at all.
5019  *
5020  * There are a number of requirements for calling this function:
5021  *
5022  * - It must be called from get_format with the same avctx parameter that was
5023  * passed to get_format. Calling it outside of get_format is not allowed, and
5024  * can trigger undefined behavior.
5025  * - The function is not always supported (see description of return values).
5026  * Even if this function returns successfully, hwaccel initialization could
5027  * fail later. (The degree to which implementations check whether the stream
5028  * is actually supported varies. Some do this check only after the user's
5029  * get_format callback returns.)
5030  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
5031  * user decides to use a AVHWFramesContext prepared with this API function,
5032  * the user must return the same hw_pix_fmt from get_format.
5033  * - The device_ref passed to this function must support the given hw_pix_fmt.
5034  * - After calling this API function, it is the user's responsibility to
5035  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
5036  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
5037  * before returning from get_format (this is implied by the normal
5038  * AVCodecContext.hw_frames_ctx API rules).
5039  * - The AVHWFramesContext parameters may change every time time get_format is
5040  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
5041  * you are inherently required to go through this process again on every
5042  * get_format call.
5043  * - It is perfectly possible to call this function without actually using
5044  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
5045  * previously initialized AVHWFramesContext, and calling this API function
5046  * only to test whether the required frame parameters have changed.
5047  * - Fields that use dynamically allocated values of any kind must not be set
5048  * by the user unless setting them is explicitly allowed by the documentation.
5049  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
5050  * the new free callback must call the potentially set previous free callback.
5051  * This API call may set any dynamically allocated fields, including the free
5052  * callback.
5053  *
5054  * The function will set at least the following fields on AVHWFramesContext
5055  * (potentially more, depending on hwaccel API):
5056  *
5057  * - All fields set by av_hwframe_ctx_alloc().
5058  * - Set the format field to hw_pix_fmt.
5059  * - Set the sw_format field to the most suited and most versatile format. (An
5060  * implication is that this will prefer generic formats over opaque formats
5061  * with arbitrary restrictions, if possible.)
5062  * - Set the width/height fields to the coded frame size, rounded up to the
5063  * API-specific minimum alignment.
5064  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
5065  * field to the number of maximum reference surfaces possible with the codec,
5066  * plus 1 surface for the user to work (meaning the user can safely reference
5067  * at most 1 decoded surface at a time), plus additional buffering introduced
5068  * by frame threading. If the hwaccel does not require pre-allocation, the
5069  * field is left to 0, and the decoder will allocate new surfaces on demand
5070  * during decoding.
5071  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
5072  * hardware API.
5073  *
5074  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
5075  * with basic frame parameters set.
5076  *
5077  * The function is stateless, and does not change the AVCodecContext or the
5078  * device_ref AVHWDeviceContext.
5079  *
5080  * @param avctx The context which is currently calling get_format, and which
5081  * implicitly contains all state needed for filling the returned
5082  * AVHWFramesContext properly.
5083  * @param device_ref A reference to the AVHWDeviceContext describing the device
5084  * which will be used by the hardware decoder.
5085  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
5086  * @param out_frames_ref On success, set to a reference to an _uninitialized_
5087  * AVHWFramesContext, created from the given device_ref.
5088  * Fields will be set to values required for decoding.
5089  * Not changed if an error is returned.
5090  * @return zero on success, a negative value on error. The following error codes
5091  * have special semantics:
5092  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
5093  * is always manual, or it is a decoder which does not
5094  * support setting AVCodecContext.hw_frames_ctx at all,
5095  * or it is a software format.
5096  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
5097  * this configuration, or the device_ref is not supported
5098  * for the hwaccel referenced by hw_pix_fmt.
5099  */
5101  AVBufferRef *device_ref,
5103  AVBufferRef **out_frames_ref);
5104 
5105 
5106 
5107 /**
5108  * @defgroup lavc_parsing Frame parsing
5109  * @{
5110  */
5111 
5114  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5115  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5116  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5117 };
5118 
5119 typedef struct AVCodecParserContext {
5120  void *priv_data;
5122  int64_t frame_offset; /* offset of the current frame */
5123  int64_t cur_offset; /* current offset
5124  (incremented by each av_parser_parse()) */
5125  int64_t next_frame_offset; /* offset of the next frame */
5126  /* video info */
5127  int pict_type; /* XXX: Put it back in AVCodecContext. */
5128  /**
5129  * This field is used for proper frame duration computation in lavf.
5130  * It signals, how much longer the frame duration of the current frame
5131  * is compared to normal frame duration.
5132  *
5133  * frame_duration = (1 + repeat_pict) * time_base
5134  *
5135  * It is used by codecs like H.264 to display telecined material.
5136  */
5137  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5138  int64_t pts; /* pts of the current frame */
5139  int64_t dts; /* dts of the current frame */
5140 
5141  /* private data */
5142  int64_t last_pts;
5143  int64_t last_dts;
5145 
5146 #define AV_PARSER_PTS_NB 4
5148  int64_t cur_frame_offset[AV_PARSER_PTS_NB];
5149  int64_t cur_frame_pts[AV_PARSER_PTS_NB];
5150  int64_t cur_frame_dts[AV_PARSER_PTS_NB];
5151 
5152  int flags;
5153 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5154 #define PARSER_FLAG_ONCE 0x0002
5155 /// Set if the parser has a valid file offset
5156 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5157 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5158 
5159  int64_t offset; ///< byte offset from starting packet start
5160  int64_t cur_frame_end[AV_PARSER_PTS_NB];
5161 
5162  /**
5163  * Set by parser to 1 for key frames and 0 for non-key frames.
5164  * It is initialized to -1, so if the parser doesn't set this flag,
5165  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5166  * will be used.
5167  */
5169 
5170 #if FF_API_CONVERGENCE_DURATION
5171  /**
5172  * @deprecated unused
5173  */
5176 #endif
5177 
5178  // Timestamp generation support:
5179  /**
5180  * Synchronization point for start of timestamp generation.
5181  *
5182  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5183  * (default).
5184  *
5185  * For example, this corresponds to presence of H.264 buffering period
5186  * SEI message.
5187  */
5189 
5190  /**
5191  * Offset of the current timestamp against last timestamp sync point in
5192  * units of AVCodecContext.time_base.
5193  *
5194  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5195  * contain a valid timestamp offset.
5196  *
5197  * Note that the timestamp of sync point has usually a nonzero
5198  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5199  * the next frame after timestamp sync point will be usually 1.
5200  *
5201  * For example, this corresponds to H.264 cpb_removal_delay.
5202  */
5204 
5205  /**
5206  * Presentation delay of current frame in units of AVCodecContext.time_base.
5207  *
5208  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5209  * contain valid non-negative timestamp delta (presentation time of a frame
5210  * must not lie in the past).
5211  *
5212  * This delay represents the difference between decoding and presentation
5213  * time of the frame.
5214  *
5215  * For example, this corresponds to H.264 dpb_output_delay.
5216  */
5218 
5219  /**
5220  * Position of the packet in file.
5221  *
5222  * Analogous to cur_frame_pts/dts
5223  */
5224  int64_t cur_frame_pos[AV_PARSER_PTS_NB];
5225 
5226  /**
5227  * Byte position of currently parsed frame in stream.
5228  */
5229  int64_t pos;
5230 
5231  /**
5232  * Previous frame byte position.
5233  */
5234  int64_t last_pos;
5235 
5236  /**
5237  * Duration of the current frame.
5238  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5239  * For all other types, this is in units of AVCodecContext.time_base.
5240  */
5242 
5243  enum AVFieldOrder field_order;
5244 
5245  /**
5246  * Indicate whether a picture is coded as a frame, top field or bottom field.
5247  *
5248  * For example, H.264 field_pic_flag equal to 0 corresponds to
5249  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5250  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5251  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5252  */
5253  enum AVPictureStructure picture_structure;
5254 
5255  /**
5256  * Picture number incremented in presentation or output order.
5257  * This field may be reinitialized at the first picture of a new sequence.
5258  *
5259  * For example, this corresponds to H.264 PicOrderCnt.
5260  */
5262 
5263  /**
5264  * Dimensions of the decoded video intended for presentation.
5265  */
5266  int width;
5267  int height;
5268 
5269  /**
5270  * Dimensions of the coded video.
5271  */
5274 
5275  /**
5276  * The format of the coded data, corresponds to enum AVPixelFormat for video
5277  * and for enum AVSampleFormat for audio.
5278  *
5279  * Note that a decoder can have considerable freedom in how exactly it
5280  * decodes the data, so the format reported here might be different from the
5281  * one returned by a decoder.
5282  */
5283  int format;
5285 
5286 typedef struct AVCodecParser {
5287  int codec_ids[5]; /* several codec IDs are permitted */
5289  int (*parser_init)(AVCodecParserContext *s);
5290  /* This callback never returns an error, a negative value means that
5291  * the frame start was in a previous packet. */
5292  int (*parser_parse)(AVCodecParserContext *s,
5293  AVCodecContext *avctx,
5294  const uint8_t **poutbuf, int *poutbuf_size,
5295  const uint8_t *buf, int buf_size);
5296  void (*parser_close)(AVCodecParserContext *s);
5297  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5299 } AVCodecParser;
5300 
5301 /**
5302  * Iterate over all registered codec parsers.
5303  *
5304  * @param opaque a pointer where libavcodec will store the iteration state. Must
5305  * point to NULL to start the iteration.
5306  *
5307  * @return the next registered codec parser or NULL when the iteration is
5308  * finished
5309  */
5310 const AVCodecParser *av_parser_iterate(void **opaque);
5311 
5314 
5318 
5319 /**
5320  * Parse a packet.
5321  *
5322  * @param s parser context.
5323  * @param avctx codec context.
5324  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5325  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5326  * @param buf input buffer.
5327  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5328  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5329  To signal EOF, this should be 0 (so that the last frame
5330  can be output).
5331  * @param pts input presentation timestamp.
5332  * @param dts input decoding timestamp.
5333  * @param pos input byte position in stream.
5334  * @return the number of bytes of the input bitstream used.
5335  *
5336  * Example:
5337  * @code
5338  * while(in_len){
5339  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5340  * in_data, in_len,
5341  * pts, dts, pos);
5342  * in_data += len;
5343  * in_len -= len;
5344  *
5345  * if(size)
5346  * decode_frame(data, size);
5347  * }
5348  * @endcode
5349  */
5351  AVCodecContext *avctx,
5352  uint8_t **poutbuf, int *poutbuf_size,
5353  const uint8_t *buf, int buf_size,
5354  int64_t pts, int64_t dts,
5355  int64_t pos);
5356 
5357 /**
5358  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5359  * @deprecated use AVBitStreamFilter
5360  */
5362  AVCodecContext *avctx,
5363  uint8_t **poutbuf, int *poutbuf_size,
5364  const uint8_t *buf, int buf_size, int keyframe);
5366 
5367 /**
5368  * @}
5369  * @}
5370  */
5371 
5372 /**
5373  * @addtogroup lavc_encoding
5374  * @{
5375  */
5376 
5377 /**
5378  * Find a registered encoder with a matching codec ID.
5379  *
5380  * @param id AVCodecID of the requested encoder
5381  * @return An encoder if one was found, NULL otherwise.
5382  */
5384 
5385 /**
5386  * Find a registered encoder with the specified name.
5387  *
5388  * @param name name of the requested encoder
5389  * @return An encoder if one was found, NULL otherwise.
5390  */
5392 
5393 /**
5394  * Encode a frame of audio.
5395  *
5396  * Takes input samples from frame and writes the next output packet, if
5397  * available, to avpkt. The output packet does not necessarily contain data for
5398  * the most recent frame, as encoders can delay, split, and combine input frames
5399  * internally as needed.
5400  *
5401  * @param avctx codec context
5402  * @param avpkt output AVPacket.
5403  * The user can supply an output buffer by setting
5404  * avpkt->data and avpkt->size prior to calling the
5405  * function, but if the size of the user-provided data is not
5406  * large enough, encoding will fail. If avpkt->data and
5407  * avpkt->size are set, avpkt->destruct must also be set. All
5408  * other AVPacket fields will be reset by the encoder using
5409  * av_init_packet(). If avpkt->data is NULL, the encoder will
5410  * allocate it. The encoder will set avpkt->size to the size
5411  * of the output packet.
5412  *
5413  * If this function fails or produces no output, avpkt will be
5414  * freed using av_packet_unref().
5415  * @param[in] frame AVFrame containing the raw audio data to be encoded.
5416  * May be NULL when flushing an encoder that has the
5417  * AV_CODEC_CAP_DELAY capability set.
5418  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5419  * can have any number of samples.
5420  * If it is not set, frame->nb_samples must be equal to
5421  * avctx->frame_size for all frames except the last.
5422  * The final frame may be smaller than avctx->frame_size.
5423  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5424  * output packet is non-empty, and to 0 if it is
5425  * empty. If the function returns an error, the
5426  * packet can be assumed to be invalid, and the
5427  * value of got_packet_ptr is undefined and should
5428  * not be used.
5429  * @return 0 on success, negative error code on failure
5430  *
5431  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5432  */
5434 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5435  const AVFrame *frame, int *got_packet_ptr);
5436 
5437 /**
5438  * Encode a frame of video.
5439  *
5440  * Takes input raw video data from frame and writes the next output packet, if
5441  * available, to avpkt. The output packet does not necessarily contain data for
5442  * the most recent frame, as encoders can delay and reorder input frames