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 
460 
461  /* various PCM "codecs" */
462  AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
494 
500 
501  /* various ADPCM codecs */
533 
545 
546  /* AMR */
549 
550  /* RealAudio codecs*/
553 
554  /* various DPCM codecs */
559 
562 
563  /* audio codecs */
564  AV_CODEC_ID_MP2 = 0x15000,
565  AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
582  AV_CODEC_ID_GSM, ///< as in Berlin toast format
594  AV_CODEC_ID_GSM_MS, /* as found in WAV */
632 
655 
656  /* subtitle codecs */
657  AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
660  AV_CODEC_ID_TEXT, ///< raw UTF-8 text
667 
685 
686  /* other specific kind of codecs (generally used for attachments) */
687  AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
688  AV_CODEC_ID_TTF = 0x18000,
689 
690  AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
699 
700 
701  AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
702 
703  AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
704  * stream (only used by libavformat) */
705  AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
706  * stream (only used by libavformat) */
707  AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
708  AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
709 };
710 
711 /**
712  * This struct describes the properties of a single codec described by an
713  * AVCodecID.
714  * @see avcodec_descriptor_get()
715  */
716 typedef struct AVCodecDescriptor {
717  enum AVCodecID id;
719  /**
720  * Name of the codec described by this descriptor. It is non-empty and
721  * unique for each codec descriptor. It should contain alphanumeric
722  * characters and '_' only.
723  */
724  const char *name;
725  /**
726  * A more descriptive name for this codec. May be NULL.
727  */
728  const char *long_name;
729  /**
730  * Codec properties, a combination of AV_CODEC_PROP_* flags.
731  */
732  int props;
733  /**
734  * MIME type(s) associated with the codec.
735  * May be NULL; if not, a NULL-terminated array of MIME types.
736  * The first item is always non-NULL and is the preferred MIME type.
737  */
738  const char *const *mime_types;
739  /**
740  * If non-NULL, an array of profiles recognized for this codec.
741  * Terminated with FF_PROFILE_UNKNOWN.
742  */
743  const struct AVProfile *profiles;
745 
746 /**
747  * Codec uses only intra compression.
748  * Video and audio codecs only.
749  */
750 #define AV_CODEC_PROP_INTRA_ONLY (1 << 0)
751 /**
752  * Codec supports lossy compression. Audio and video codecs only.
753  * @note a codec may support both lossy and lossless
754  * compression modes
755  */
756 #define AV_CODEC_PROP_LOSSY (1 << 1)
757 /**
758  * Codec supports lossless compression. Audio and video codecs only.
759  */
760 #define AV_CODEC_PROP_LOSSLESS (1 << 2)
761 /**
762  * Codec supports frame reordering. That is, the coded order (the order in which
763  * the encoded packets are output by the encoders / stored / input to the
764  * decoders) may be different from the presentation order of the corresponding
765  * frames.
766  *
767  * For codecs that do not have this property set, PTS and DTS should always be
768  * equal.
769  */
770 #define AV_CODEC_PROP_REORDER (1 << 3)
771 /**
772  * Subtitle codec is bitmap based
773  * Decoded AVSubtitle data can be read from the AVSubtitleRect->pict field.
774  */
775 #define AV_CODEC_PROP_BITMAP_SUB (1 << 16)
776 /**
777  * Subtitle codec is text based.
778  * Decoded AVSubtitle data can be read from the AVSubtitleRect->ass field.
779  */
780 #define AV_CODEC_PROP_TEXT_SUB (1 << 17)
781 
782 /**
783  * @ingroup lavc_decoding
784  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
785  * This is mainly needed because some optimized bitstream readers read
786  * 32 or 64 bit at once and could read over the end.<br>
787  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
788  * MPEG bitstreams could cause overread and segfault.
789  */
790 #define AV_INPUT_BUFFER_PADDING_SIZE 64
791 
792 /**
793  * @ingroup lavc_encoding
794  * minimum encoding buffer size
795  * Used to avoid some checks during header writing.
796  */
797 #define AV_INPUT_BUFFER_MIN_SIZE 16384
798 
799 /**
800  * @ingroup lavc_decoding
801  */
803  /* We leave some space between them for extensions (drop some
804  * keyframes for intra-only or drop just some bidir frames). */
805  AVDISCARD_NONE =-16, ///< discard nothing
806  AVDISCARD_DEFAULT = 0, ///< discard useless packets like 0 size packets in avi
807  AVDISCARD_NONREF = 8, ///< discard all non reference
808  AVDISCARD_BIDIR = 16, ///< discard all bidirectional frames
809  AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
810  AVDISCARD_NONKEY = 32, ///< discard all frames except keyframes
811  AVDISCARD_ALL = 48, ///< discard all
812 };
813 
824  AV_AUDIO_SERVICE_TYPE_NB , ///< Not part of ABI
825 };
826 
827 /**
828  * @ingroup lavc_encoding
829  */
830 typedef struct RcOverride{
833  int qscale; // If this is 0 then quality_factor will be used instead.
835 } RcOverride;
836 
837 /* encoding support
838  These flags can be passed in AVCodecContext.flags before initialization.
839  Note: Not everything is supported yet.
840 */
841 
842 /**
843  * Allow decoders to produce frames with data planes that are not aligned
844  * to CPU requirements (e.g. due to cropping).
845  */
846 #define AV_CODEC_FLAG_UNALIGNED (1 << 0)
847 /**
848  * Use fixed qscale.
849  */
850 #define AV_CODEC_FLAG_QSCALE (1 << 1)
851 /**
852  * 4 MV per MB allowed / advanced prediction for H.263.
853  */
854 #define AV_CODEC_FLAG_4MV (1 << 2)
855 /**
856  * Output even those frames that might be corrupted.
857  */
858 #define AV_CODEC_FLAG_OUTPUT_CORRUPT (1 << 3)
859 /**
860  * Use qpel MC.
861  */
862 #define AV_CODEC_FLAG_QPEL (1 << 4)
863 /**
864  * Don't output frames whose parameters differ from first
865  * decoded frame in stream.
866  */
867 #define AV_CODEC_FLAG_DROPCHANGED (1 << 5)
868 /**
869  * Use internal 2pass ratecontrol in first pass mode.
870  */
871 #define AV_CODEC_FLAG_PASS1 (1 << 9)
872 /**
873  * Use internal 2pass ratecontrol in second pass mode.
874  */
875 #define AV_CODEC_FLAG_PASS2 (1 << 10)
876 /**
877  * loop filter.
878  */
879 #define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
880 /**
881  * Only decode/encode grayscale.
882  */
883 #define AV_CODEC_FLAG_GRAY (1 << 13)
884 /**
885  * error[?] variables will be set during encoding.
886  */
887 #define AV_CODEC_FLAG_PSNR (1 << 15)
888 /**
889  * Input bitstream might be truncated at a random location
890  * instead of only at frame boundaries.
891  */
892 #define AV_CODEC_FLAG_TRUNCATED (1 << 16)
893 /**
894  * Use interlaced DCT.
895  */
896 #define AV_CODEC_FLAG_INTERLACED_DCT (1 << 18)
897 /**
898  * Force low delay.
899  */
900 #define AV_CODEC_FLAG_LOW_DELAY (1 << 19)
901 /**
902  * Place global headers in extradata instead of every keyframe.
903  */
904 #define AV_CODEC_FLAG_GLOBAL_HEADER (1 << 22)
905 /**
906  * Use only bitexact stuff (except (I)DCT).
907  */
908 #define AV_CODEC_FLAG_BITEXACT (1 << 23)
909 /* Fx : Flag for H.263+ extra options */
910 /**
911  * H.263 advanced intra coding / MPEG-4 AC prediction
912  */
913 #define AV_CODEC_FLAG_AC_PRED (1 << 24)
914 /**
915  * interlaced motion estimation
916  */
917 #define AV_CODEC_FLAG_INTERLACED_ME (1 << 29)
918 #define AV_CODEC_FLAG_CLOSED_GOP (1U << 31)
919 
920 /**
921  * Allow non spec compliant speedup tricks.
922  */
923 #define AV_CODEC_FLAG2_FAST (1 << 0)
924 /**
925  * Skip bitstream encoding.
926  */
927 #define AV_CODEC_FLAG2_NO_OUTPUT (1 << 2)
928 /**
929  * Place global headers at every keyframe instead of in extradata.
930  */
931 #define AV_CODEC_FLAG2_LOCAL_HEADER (1 << 3)
932 
933 /**
934  * timecode is in drop frame format. DEPRECATED!!!!
935  */
936 #define AV_CODEC_FLAG2_DROP_FRAME_TIMECODE (1 << 13)
937 
938 /**
939  * Input bitstream might be truncated at a packet boundaries
940  * instead of only at frame boundaries.
941  */
942 #define AV_CODEC_FLAG2_CHUNKS (1 << 15)
943 /**
944  * Discard cropping information from SPS.
945  */
946 #define AV_CODEC_FLAG2_IGNORE_CROP (1 << 16)
947 
948 /**
949  * Show all frames before the first keyframe
950  */
951 #define AV_CODEC_FLAG2_SHOW_ALL (1 << 22)
952 /**
953  * Export motion vectors through frame side data
954  */
955 #define AV_CODEC_FLAG2_EXPORT_MVS (1 << 28)
956 /**
957  * Do not skip samples and export skip information as frame side data
958  */
959 #define AV_CODEC_FLAG2_SKIP_MANUAL (1 << 29)
960 /**
961  * Do not reset ASS ReadOrder field on flush (subtitles decoding)
962  */
963 #define AV_CODEC_FLAG2_RO_FLUSH_NOOP (1 << 30)
964 
965 /* Unsupported options :
966  * Syntax Arithmetic coding (SAC)
967  * Reference Picture Selection
968  * Independent Segment Decoding */
969 /* /Fx */
970 /* codec capabilities */
971 
972 /**
973  * Decoder can use draw_horiz_band callback.
974  */
975 #define AV_CODEC_CAP_DRAW_HORIZ_BAND (1 << 0)
976 /**
977  * Codec uses get_buffer() for allocating buffers and supports custom allocators.
978  * If not set, it might not use get_buffer() at all or use operations that
979  * assume the buffer was allocated by avcodec_default_get_buffer.
980  */
981 #define AV_CODEC_CAP_DR1 (1 << 1)
982 #define AV_CODEC_CAP_TRUNCATED (1 << 3)
983 /**
984  * Encoder or decoder requires flushing with NULL input at the end in order to
985  * give the complete and correct output.
986  *
987  * NOTE: If this flag is not set, the codec is guaranteed to never be fed with
988  * with NULL data. The user can still send NULL data to the public encode
989  * or decode function, but libavcodec will not pass it along to the codec
990  * unless this flag is set.
991  *
992  * Decoders:
993  * The decoder has a non-zero delay and needs to be fed with avpkt->data=NULL,
994  * avpkt->size=0 at the end to get the delayed data until the decoder no longer
995  * returns frames.
996  *
997  * Encoders:
998  * The encoder needs to be fed with NULL data at the end of encoding until the
999  * encoder no longer returns data.
1000  *
1001  * NOTE: For encoders implementing the AVCodec.encode2() function, setting this
1002  * flag also means that the encoder must set the pts and duration for
1003  * each output packet. If this flag is not set, the pts and duration will
1004  * be determined by libavcodec from the input frame.
1005  */
1006 #define AV_CODEC_CAP_DELAY (1 << 5)
1007 /**
1008  * Codec can be fed a final frame with a smaller size.
1009  * This can be used to prevent truncation of the last audio samples.
1010  */
1011 #define AV_CODEC_CAP_SMALL_LAST_FRAME (1 << 6)
1012 
1013 /**
1014  * Codec can output multiple frames per AVPacket
1015  * Normally demuxers return one frame at a time, demuxers which do not do
1016  * are connected to a parser to split what they return into proper frames.
1017  * This flag is reserved to the very rare category of codecs which have a
1018  * bitstream that cannot be split into frames without timeconsuming
1019  * operations like full decoding. Demuxers carrying such bitstreams thus
1020  * may return multiple frames in a packet. This has many disadvantages like
1021  * prohibiting stream copy in many cases thus it should only be considered
1022  * as a last resort.
1023  */
1024 #define AV_CODEC_CAP_SUBFRAMES (1 << 8)
1025 /**
1026  * Codec is experimental and is thus avoided in favor of non experimental
1027  * encoders
1028  */
1029 #define AV_CODEC_CAP_EXPERIMENTAL (1 << 9)
1030 /**
1031  * Codec should fill in channel configuration and samplerate instead of container
1032  */
1033 #define AV_CODEC_CAP_CHANNEL_CONF (1 << 10)
1034 /**
1035  * Codec supports frame-level multithreading.
1036  */
1037 #define AV_CODEC_CAP_FRAME_THREADS (1 << 12)
1038 /**
1039  * Codec supports slice-based (or partition-based) multithreading.
1040  */
1041 #define AV_CODEC_CAP_SLICE_THREADS (1 << 13)
1042 /**
1043  * Codec supports changed parameters at any point.
1044  */
1045 #define AV_CODEC_CAP_PARAM_CHANGE (1 << 14)
1046 /**
1047  * Codec supports avctx->thread_count == 0 (auto).
1048  */
1049 #define AV_CODEC_CAP_AUTO_THREADS (1 << 15)
1050 /**
1051  * Audio encoder supports receiving a different number of samples in each call.
1052  */
1053 #define AV_CODEC_CAP_VARIABLE_FRAME_SIZE (1 << 16)
1054 /**
1055  * Decoder is not a preferred choice for probing.
1056  * This indicates that the decoder is not a good choice for probing.
1057  * It could for example be an expensive to spin up hardware decoder,
1058  * or it could simply not provide a lot of useful information about
1059  * the stream.
1060  * A decoder marked with this flag should only be used as last resort
1061  * choice for probing.
1062  */
1063 #define AV_CODEC_CAP_AVOID_PROBING (1 << 17)
1064 /**
1065  * Codec is intra only.
1066  */
1067 #define AV_CODEC_CAP_INTRA_ONLY 0x40000000
1068 /**
1069  * Codec is lossless.
1070  */
1071 #define AV_CODEC_CAP_LOSSLESS 0x80000000
1072 
1073 /**
1074  * Codec is backed by a hardware implementation. Typically used to
1075  * identify a non-hwaccel hardware decoder. For information about hwaccels, use
1076  * avcodec_get_hw_config() instead.
1077  */
1078 #define AV_CODEC_CAP_HARDWARE (1 << 18)
1079 
1080 /**
1081  * Codec is potentially backed by a hardware implementation, but not
1082  * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
1083  * implementation provides some sort of internal fallback.
1084  */
1085 #define AV_CODEC_CAP_HYBRID (1 << 19)
1086 
1087 /**
1088  * This codec takes the reordered_opaque field from input AVFrames
1089  * and returns it in the corresponding field in AVCodecContext after
1090  * encoding.
1091  */
1092 #define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE (1 << 20)
1093 
1094 /**
1095  * Pan Scan area.
1096  * This specifies the area which should be displayed.
1097  * Note there may be multiple such areas for one frame.
1098  */
1099 typedef struct AVPanScan {
1100  /**
1101  * id
1102  * - encoding: Set by user.
1103  * - decoding: Set by libavcodec.
1104  */
1105  int id;
1106 
1107  /**
1108  * width and height in 1/16 pel
1109  * - encoding: Set by user.
1110  * - decoding: Set by libavcodec.
1111  */
1112  int width;
1113  int height;
1114 
1115  /**
1116  * position of the top left corner in 1/16 pel for up to 3 fields/frames
1117  * - encoding: Set by user.
1118  * - decoding: Set by libavcodec.
1119  */
1120  int16_t position[3][2];
1121 } AVPanScan;
1122 
1123 /**
1124  * This structure describes the bitrate properties of an encoded bitstream. It
1125  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
1126  * parameters for H.264/HEVC.
1127  */
1128 typedef struct AVCPBProperties {
1129  /**
1130  * Maximum bitrate of the stream, in bits per second.
1131  * Zero if unknown or unspecified.
1132  */
1133 #if FF_API_UNSANITIZED_BITRATES
1135 #else
1136  int64_t max_bitrate;
1137 #endif
1138  /**
1139  * Minimum bitrate of the stream, in bits per second.
1140  * Zero if unknown or unspecified.
1141  */
1142 #if FF_API_UNSANITIZED_BITRATES
1144 #else
1145  int64_t min_bitrate;
1146 #endif
1147  /**
1148  * Average bitrate of the stream, in bits per second.
1149  * Zero if unknown or unspecified.
1150  */
1151 #if FF_API_UNSANITIZED_BITRATES
1153 #else
1154  int64_t avg_bitrate;
1155 #endif
1156 
1157  /**
1158  * The size of the buffer to which the ratecontrol is applied, in bits.
1159  * Zero if unknown or unspecified.
1160  */
1162 
1163  /**
1164  * The delay between the time the packet this structure is associated with
1165  * is received and the time when it should be decoded, in periods of a 27MHz
1166  * clock.
1167  *
1168  * UINT64_MAX when unknown or unspecified.
1169  */
1170  uint64_t vbv_delay;
1171 } AVCPBProperties;
1172 
1173 /**
1174  * The decoder will keep a reference to the frame and may reuse it later.
1175  */
1176 #define AV_GET_BUFFER_FLAG_REF (1 << 0)
1177 
1178 /**
1179  * @defgroup lavc_packet AVPacket
1180  *
1181  * Types and functions for working with AVPacket.
1182  * @{
1183  */
1185  /**
1186  * An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE
1187  * bytes worth of palette. This side data signals that a new palette is
1188  * present.
1189  */
1191 
1192  /**
1193  * The AV_PKT_DATA_NEW_EXTRADATA is used to notify the codec or the format
1194  * that the extradata buffer was changed and the receiving side should
1195  * act upon it appropriately. The new extradata is embedded in the side
1196  * data buffer and should be immediately used for processing the current
1197  * frame or packet.
1198  */
1200 
1201  /**
1202  * An AV_PKT_DATA_PARAM_CHANGE side data packet is laid out as follows:
1203  * @code
1204  * u32le param_flags
1205  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT)
1206  * s32le channel_count
1207  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT)
1208  * u64le channel_layout
1209  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE)
1210  * s32le sample_rate
1211  * if (param_flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS)
1212  * s32le width
1213  * s32le height
1214  * @endcode
1215  */
1217 
1218  /**
1219  * An AV_PKT_DATA_H263_MB_INFO side data packet contains a number of
1220  * structures with info about macroblocks relevant to splitting the
1221  * packet into smaller packets on macroblock edges (e.g. as for RFC 2190).
1222  * That is, it does not necessarily contain info about all macroblocks,
1223  * as long as the distance between macroblocks in the info is smaller
1224  * than the target payload size.
1225  * Each MB info structure is 12 bytes, and is laid out as follows:
1226  * @code
1227  * u32le bit offset from the start of the packet
1228  * u8 current quantizer at the start of the macroblock
1229  * u8 GOB number
1230  * u16le macroblock address within the GOB
1231  * u8 horizontal MV predictor
1232  * u8 vertical MV predictor
1233  * u8 horizontal MV predictor for block number 3
1234  * u8 vertical MV predictor for block number 3
1235  * @endcode
1236  */
1238 
1239  /**
1240  * This side data should be associated with an audio stream and contains
1241  * ReplayGain information in form of the AVReplayGain struct.
1242  */
1244 
1245  /**
1246  * This side data contains a 3x3 transformation matrix describing an affine
1247  * transformation that needs to be applied to the decoded video frames for
1248  * correct presentation.
1249  *
1250  * See libavutil/display.h for a detailed description of the data.
1251  */
1253 
1254  /**
1255  * This side data should be associated with a video stream and contains
1256  * Stereoscopic 3D information in form of the AVStereo3D struct.
1257  */
1259 
1260  /**
1261  * This side data should be associated with an audio stream and corresponds
1262  * to enum AVAudioServiceType.
1263  */
1265 
1266  /**
1267  * This side data contains quality related information from the encoder.
1268  * @code
1269  * u32le quality factor of the compressed frame. Allowed range is between 1 (good) and FF_LAMBDA_MAX (bad).
1270  * u8 picture type
1271  * u8 error count
1272  * u16 reserved
1273  * u64le[error count] sum of squared differences between encoder in and output
1274  * @endcode
1275  */
1277 
1278  /**
1279  * This side data contains an integer value representing the stream index
1280  * of a "fallback" track. A fallback track indicates an alternate
1281  * track to use when the current track can not be decoded for some reason.
1282  * e.g. no decoder available for codec.
1283  */
1285 
1286  /**
1287  * This side data corresponds to the AVCPBProperties struct.
1288  */
1290 
1291  /**
1292  * Recommmends skipping the specified number of samples
1293  * @code
1294  * u32le number of samples to skip from start of this packet
1295  * u32le number of samples to skip from end of this packet
1296  * u8 reason for start skip
1297  * u8 reason for end skip (0=padding silence, 1=convergence)
1298  * @endcode
1299  */
1301 
1302  /**
1303  * An AV_PKT_DATA_JP_DUALMONO side data packet indicates that
1304  * the packet may contain "dual mono" audio specific to Japanese DTV
1305  * and if it is true, recommends only the selected channel to be used.
1306  * @code
1307  * u8 selected channels (0=mail/left, 1=sub/right, 2=both)
1308  * @endcode
1309  */
1311 
1312  /**
1313  * A list of zero terminated key/value strings. There is no end marker for
1314  * the list, so it is required to rely on the side data size to stop.
1315  */
1317 
1318  /**
1319  * Subtitle event position
1320  * @code
1321  * u32le x1
1322  * u32le y1
1323  * u32le x2
1324  * u32le y2
1325  * @endcode
1326  */
1328 
1329  /**
1330  * Data found in BlockAdditional element of matroska container. There is
1331  * no end marker for the data, so it is required to rely on the side data
1332  * size to recognize the end. 8 byte id (as found in BlockAddId) followed
1333  * by data.
1334  */
1336 
1337  /**
1338  * The optional first identifier line of a WebVTT cue.
1339  */
1341 
1342  /**
1343  * The optional settings (rendering instructions) that immediately
1344  * follow the timestamp specifier of a WebVTT cue.
1345  */
1347 
1348  /**
1349  * A list of zero terminated key/value strings. There is no end marker for
1350  * the list, so it is required to rely on the side data size to stop. This
1351  * side data includes updated metadata which appeared in the stream.
1352  */
1354 
1355  /**
1356  * MPEGTS stream ID as uint8_t, this is required to pass the stream ID
1357  * information from the demuxer to the corresponding muxer.
1358  */
1360 
1361  /**
1362  * Mastering display metadata (based on SMPTE-2086:2014). This metadata
1363  * should be associated with a video stream and contains data in the form
1364  * of the AVMasteringDisplayMetadata struct.
1365  */
1367 
1368  /**
1369  * This side data should be associated with a video stream and corresponds
1370  * to the AVSphericalMapping structure.
1371  */
1373 
1374  /**
1375  * Content light level (based on CTA-861.3). This metadata should be
1376  * associated with a video stream and contains data in the form of the
1377  * AVContentLightMetadata struct.
1378  */
1380 
1381  /**
1382  * ATSC A53 Part 4 Closed Captions. This metadata should be associated with
1383  * a video stream. A53 CC bitstream is stored as uint8_t in AVPacketSideData.data.
1384  * The number of bytes of CC data is AVPacketSideData.size.
1385  */
1387 
1388  /**
1389  * This side data is encryption initialization data.
1390  * The format is not part of ABI, use av_encryption_init_info_* methods to
1391  * access.
1392  */
1394 
1395  /**
1396  * This side data contains encryption info for how to decrypt the packet.
1397  * The format is not part of ABI, use av_encryption_info_* methods to access.
1398  */
1400 
1401  /**
1402  * Active Format Description data consisting of a single byte as specified
1403  * in ETSI TS 101 154 using AVActiveFormatDescription enum.
1404  */
1406 
1407  /**
1408  * The number of side data types.
1409  * This is not part of the public API/ABI in the sense that it may
1410  * change when new side data types are added.
1411  * This must stay the last enum value.
1412  * If its value becomes huge, some code using it
1413  * needs to be updated as it assumes it to be smaller than other limits.
1414  */
1416 };
1417 
1418 #define AV_PKT_DATA_QUALITY_FACTOR AV_PKT_DATA_QUALITY_STATS //DEPRECATED
1419 
1420 typedef struct AVPacketSideData {
1422  int size;
1425 
1426 /**
1427  * This structure stores compressed data. It is typically exported by demuxers
1428  * and then passed as input to decoders, or received as output from encoders and
1429  * then passed to muxers.
1430  *
1431  * For video, it should typically contain one compressed frame. For audio it may
1432  * contain several compressed frames. Encoders are allowed to output empty
1433  * packets, with no compressed data, containing only side data
1434  * (e.g. to update some stream parameters at the end of encoding).
1435  *
1436  * AVPacket is one of the few structs in FFmpeg, whose size is a part of public
1437  * ABI. Thus it may be allocated on stack and no new fields can be added to it
1438  * without libavcodec and libavformat major bump.
1439  *
1440  * The semantics of data ownership depends on the buf field.
1441  * If it is set, the packet data is dynamically allocated and is
1442  * valid indefinitely until a call to av_packet_unref() reduces the
1443  * reference count to 0.
1444  *
1445  * If the buf field is not set av_packet_ref() would make a copy instead
1446  * of increasing the reference count.
1447  *
1448  * The side data is always allocated with av_malloc(), copied by
1449  * av_packet_ref() and freed by av_packet_unref().
1450  *
1451  * @see av_packet_ref
1452  * @see av_packet_unref
1453  */
1454 typedef struct AVPacket {
1455  /**
1456  * A reference to the reference-counted buffer where the packet data is
1457  * stored.
1458  * May be NULL, then the packet data is not reference-counted.
1459  */
1461  /**
1462  * Presentation timestamp in AVStream->time_base units; the time at which
1463  * the decompressed packet will be presented to the user.
1464  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1465  * pts MUST be larger or equal to dts as presentation cannot happen before
1466  * decompression, unless one wants to view hex dumps. Some formats misuse
1467  * the terms dts and pts/cts to mean something different. Such timestamps
1468  * must be converted to true pts/dts before they are stored in AVPacket.
1469  */
1470  int64_t pts;
1471  /**
1472  * Decompression timestamp in AVStream->time_base units; the time at which
1473  * the packet is decompressed.
1474  * Can be AV_NOPTS_VALUE if it is not stored in the file.
1475  */
1476  int64_t dts;
1478  int size;
1480  /**
1481  * A combination of AV_PKT_FLAG values
1482  */
1483  int flags;
1484  /**
1485  * Additional packet data that can be provided by the container.
1486  * Packet can contain several types of side information.
1487  */
1490 
1491  /**
1492  * Duration of this packet in AVStream->time_base units, 0 if unknown.
1493  * Equals next_pts - this_pts in presentation order.
1494  */
1495  int64_t duration;
1496 
1497  int64_t pos; ///< byte position in stream, -1 if unknown
1498 
1499 #if FF_API_CONVERGENCE_DURATION
1500  /**
1501  * @deprecated Same as the duration field, but as int64_t. This was required
1502  * for Matroska subtitles, whose duration values could overflow when the
1503  * duration field was still an int.
1504  */
1507 #endif
1508 } AVPacket;
1509 #define AV_PKT_FLAG_KEY 0x0001 ///< The packet contains a keyframe
1510 #define AV_PKT_FLAG_CORRUPT 0x0002 ///< The packet content is corrupted
1511 /**
1512  * Flag is used to discard packets which are required to maintain valid
1513  * decoder state but are not required for output and should be dropped
1514  * after decoding.
1515  **/
1516 #define AV_PKT_FLAG_DISCARD 0x0004
1517 /**
1518  * The packet comes from a trusted source.
1519  *
1520  * Otherwise-unsafe constructs such as arbitrary pointers to data
1521  * outside the packet may be followed.
1522  */
1523 #define AV_PKT_FLAG_TRUSTED 0x0008
1524 /**
1525  * Flag is used to indicate packets that contain frames that can
1526  * be discarded by the decoder. I.e. Non-reference frames.
1527  */
1528 #define AV_PKT_FLAG_DISPOSABLE 0x0010
1529 
1530 
1536 };
1537 /**
1538  * @}
1539  */
1540 
1541 struct AVCodecInternal;
1542 
1546  AV_FIELD_TT, //< Top coded_first, top displayed first
1547  AV_FIELD_BB, //< Bottom coded first, bottom displayed first
1548  AV_FIELD_TB, //< Top coded first, bottom displayed first
1549  AV_FIELD_BT, //< Bottom coded first, top displayed first
1550 };
1551 
1552 /**
1553  * main external API structure.
1554  * New fields can be added to the end with minor version bumps.
1555  * Removal, reordering and changes to existing fields require a major
1556  * version bump.
1557  * You can use AVOptions (av_opt* / av_set/get*()) to access these fields from user
1558  * applications.
1559  * The name string for AVOptions options matches the associated command line
1560  * parameter name and can be found in libavcodec/options_table.h
1561  * The AVOption/command line parameter names differ in some cases from the C
1562  * structure field names for historic reasons or brevity.
1563  * sizeof(AVCodecContext) must not be used outside libav*.
1564  */
1565 typedef struct AVCodecContext {
1566  /**
1567  * information on struct for av_log
1568  * - set by avcodec_alloc_context3
1569  */
1572 
1573  enum AVMediaType codec_type; /* see AVMEDIA_TYPE_xxx */
1574  const struct AVCodec *codec;
1575  enum AVCodecID codec_id; /* see AV_CODEC_ID_xxx */
1576 
1577  /**
1578  * fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
1579  * This is used to work around some encoder bugs.
1580  * A demuxer should set this to what is stored in the field used to identify the codec.
1581  * If there are multiple such fields in a container then the demuxer should choose the one
1582  * which maximizes the information about the used codec.
1583  * If the codec tag field in a container is larger than 32 bits then the demuxer should
1584  * remap the longer ID to 32 bits with a table or other structure. Alternatively a new
1585  * extra_codec_tag + size could be added but for this a clear advantage must be demonstrated
1586  * first.
1587  * - encoding: Set by user, if not then the default based on codec_id will be used.
1588  * - decoding: Set by user, will be converted to uppercase by libavcodec during init.
1589  */
1590  unsigned int codec_tag;
1591 
1592  void *priv_data;
1593 
1594  /**
1595  * Private context used for internal data.
1596  *
1597  * Unlike priv_data, this is not codec-specific. It is used in general
1598  * libavcodec functions.
1599  */
1600  struct AVCodecInternal *internal;
1601 
1602  /**
1603  * Private data of the user, can be used to carry app specific stuff.
1604  * - encoding: Set by user.
1605  * - decoding: Set by user.
1606  */
1607  void *opaque;
1608 
1609  /**
1610  * the average bitrate
1611  * - encoding: Set by user; unused for constant quantizer encoding.
1612  * - decoding: Set by user, may be overwritten by libavcodec
1613  * if this info is available in the stream
1614  */
1615  int64_t bit_rate;
1616 
1617  /**
1618  * number of bits the bitstream is allowed to diverge from the reference.
1619  * the reference can be CBR (for CBR pass1) or VBR (for pass2)
1620  * - encoding: Set by user; unused for constant quantizer encoding.
1621  * - decoding: unused
1622  */
1624 
1625  /**
1626  * Global quality for codecs which cannot change it per frame.
1627  * This should be proportional to MPEG-1/2/4 qscale.
1628  * - encoding: Set by user.
1629  * - decoding: unused
1630  */
1632 
1633  /**
1634  * - encoding: Set by user.
1635  * - decoding: unused
1636  */
1638 #define FF_COMPRESSION_DEFAULT -1
1639 
1640  /**
1641  * AV_CODEC_FLAG_*.
1642  * - encoding: Set by user.
1643  * - decoding: Set by user.
1644  */
1645  int flags;
1646 
1647  /**
1648  * AV_CODEC_FLAG2_*
1649  * - encoding: Set by user.
1650  * - decoding: Set by user.
1651  */
1652  int flags2;
1653 
1654  /**
1655  * some codecs need / can use extradata like Huffman tables.
1656  * MJPEG: Huffman tables
1657  * rv10: additional flags
1658  * MPEG-4: global headers (they can be in the bitstream or here)
1659  * The allocated memory should be AV_INPUT_BUFFER_PADDING_SIZE bytes larger
1660  * than extradata_size to avoid problems if it is read with the bitstream reader.
1661  * The bytewise contents of extradata must not depend on the architecture or CPU endianness.
1662  * Must be allocated with the av_malloc() family of functions.
1663  * - encoding: Set/allocated/freed by libavcodec.
1664  * - decoding: Set/allocated/freed by user.
1665  */
1668 
1669  /**
1670  * This is the fundamental unit of time (in seconds) in terms
1671  * of which frame timestamps are represented. For fixed-fps content,
1672  * timebase should be 1/framerate and timestamp increments should be
1673  * identically 1.
1674  * This often, but not always is the inverse of the frame rate or field rate
1675  * for video. 1/time_base is not the average frame rate if the frame rate is not
1676  * constant.
1677  *
1678  * Like containers, elementary streams also can store timestamps, 1/time_base
1679  * is the unit in which these timestamps are specified.
1680  * As example of such codec time base see ISO/IEC 14496-2:2001(E)
1681  * vop_time_increment_resolution and fixed_vop_rate
1682  * (fixed_vop_rate == 0 implies that it is different from the framerate)
1683  *
1684  * - encoding: MUST be set by user.
1685  * - decoding: the use of this field for decoding is deprecated.
1686  * Use framerate instead.
1687  */
1689 
1690  /**
1691  * For some codecs, the time base is closer to the field rate than the frame rate.
1692  * Most notably, H.264 and MPEG-2 specify time_base as half of frame duration
1693  * if no telecine is used ...
1694  *
1695  * Set to time_base ticks per frame. Default 1, e.g., H.264/MPEG-2 set it to 2.
1696  */
1698 
1699  /**
1700  * Codec delay.
1701  *
1702  * Encoding: Number of frames delay there will be from the encoder input to
1703  * the decoder output. (we assume the decoder matches the spec)
1704  * Decoding: Number of frames delay in addition to what a standard decoder
1705  * as specified in the spec would produce.
1706  *
1707  * Video:
1708  * Number of frames the decoded output will be delayed relative to the
1709  * encoded input.
1710  *
1711  * Audio:
1712  * For encoding, this field is unused (see initial_padding).
1713  *
1714  * For decoding, this is the number of samples the decoder needs to
1715  * output before the decoder's output is valid. When seeking, you should
1716  * start decoding this many samples prior to your desired seek point.
1717  *
1718  * - encoding: Set by libavcodec.
1719  * - decoding: Set by libavcodec.
1720  */
1721  int delay;
1722 
1723 
1724  /* video only */
1725  /**
1726  * picture width / height.
1727  *
1728  * @note Those fields may not match the values of the last
1729  * AVFrame output by avcodec_decode_video2 due frame
1730  * reordering.
1731  *
1732  * - encoding: MUST be set by user.
1733  * - decoding: May be set by the user before opening the decoder if known e.g.
1734  * from the container. Some decoders will require the dimensions
1735  * to be set by the caller. During decoding, the decoder may
1736  * overwrite those values as required while parsing the data.
1737  */
1739 
1740  /**
1741  * Bitstream width / height, may be different from width/height e.g. when
1742  * the decoded frame is cropped before being output or lowres is enabled.
1743  *
1744  * @note Those field may not match the value of the last
1745  * AVFrame output by avcodec_receive_frame() due frame
1746  * reordering.
1747  *
1748  * - encoding: unused
1749  * - decoding: May be set by the user before opening the decoder if known
1750  * e.g. from the container. During decoding, the decoder may
1751  * overwrite those values as required while parsing the data.
1752  */
1753  int coded_width, coded_height;
1754 
1755  /**
1756  * the number of pictures in a group of pictures, or 0 for intra_only
1757  * - encoding: Set by user.
1758  * - decoding: unused
1759  */
1761 
1762  /**
1763  * Pixel format, see AV_PIX_FMT_xxx.
1764  * May be set by the demuxer if known from headers.
1765  * May be overridden by the decoder if it knows better.
1766  *
1767  * @note This field may not match the value of the last
1768  * AVFrame output by avcodec_receive_frame() due frame
1769  * reordering.
1770  *
1771  * - encoding: Set by user.
1772  * - decoding: Set by user if known, overridden by libavcodec while
1773  * parsing the data.
1774  */
1776 
1777  /**
1778  * If non NULL, 'draw_horiz_band' is called by the libavcodec
1779  * decoder to draw a horizontal band. It improves cache usage. Not
1780  * all codecs can do that. You must check the codec capabilities
1781  * beforehand.
1782  * When multithreading is used, it may be called from multiple threads
1783  * at the same time; threads might draw different parts of the same AVFrame,
1784  * or multiple AVFrames, and there is no guarantee that slices will be drawn
1785  * in order.
1786  * The function is also used by hardware acceleration APIs.
1787  * It is called at least once during frame decoding to pass
1788  * the data needed for hardware render.
1789  * In that mode instead of pixel data, AVFrame points to
1790  * a structure specific to the acceleration API. The application
1791  * reads the structure and can change some fields to indicate progress
1792  * or mark state.
1793  * - encoding: unused
1794  * - decoding: Set by user.
1795  * @param height the height of the slice
1796  * @param y the y position of the slice
1797  * @param type 1->top field, 2->bottom field, 3->frame
1798  * @param offset offset into the AVFrame.data from which the slice should be read
1799  */
1801  const AVFrame *src, int offset[AV_NUM_DATA_POINTERS],
1802  int y, int type, int height);
1803 
1804  /**
1805  * callback to negotiate the pixelFormat
1806  * @param fmt is the list of formats which are supported by the codec,
1807  * it is terminated by -1 as 0 is a valid format, the formats are ordered by quality.
1808  * The first is always the native one.
1809  * @note The callback may be called again immediately if initialization for
1810  * the selected (hardware-accelerated) pixel format failed.
1811  * @warning Behavior is undefined if the callback returns a value not
1812  * in the fmt list of formats.
1813  * @return the chosen format
1814  * - encoding: unused
1815  * - decoding: Set by user, if not set the native format will be chosen.
1816  */
1817  enum AVPixelFormat (*get_format)(struct AVCodecContext *s, const enum AVPixelFormat * fmt);
1818 
1819  /**
1820  * maximum number of B-frames between non-B-frames
1821  * Note: The output will be delayed by max_b_frames+1 relative to the input.
1822  * - encoding: Set by user.
1823  * - decoding: unused
1824  */
1826 
1827  /**
1828  * qscale factor between IP and B-frames
1829  * If > 0 then the last P-frame quantizer will be used (q= lastp_q*factor+offset).
1830  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1831  * - encoding: Set by user.
1832  * - decoding: unused
1833  */
1835 
1836 #if FF_API_PRIVATE_OPT
1837  /** @deprecated use encoder private options instead */
1840 #endif
1841 
1842  /**
1843  * qscale offset between IP and B-frames
1844  * - encoding: Set by user.
1845  * - decoding: unused
1846  */
1848 
1849  /**
1850  * Size of the frame reordering buffer in the decoder.
1851  * For MPEG-2 it is 1 IPB or 0 low delay IP.
1852  * - encoding: Set by libavcodec.
1853  * - decoding: Set by libavcodec.
1854  */
1856 
1857 #if FF_API_PRIVATE_OPT
1858  /** @deprecated use encoder private options instead */
1861 #endif
1862 
1863  /**
1864  * qscale factor between P- and I-frames
1865  * If > 0 then the last P-frame quantizer will be used (q = lastp_q * factor + offset).
1866  * If < 0 then normal ratecontrol will be done (q= -normal_q*factor+offset).
1867  * - encoding: Set by user.
1868  * - decoding: unused
1869  */
1871 
1872  /**
1873  * qscale offset between P and I-frames
1874  * - encoding: Set by user.
1875  * - decoding: unused
1876  */
1878 
1879  /**
1880  * luminance masking (0-> disabled)
1881  * - encoding: Set by user.
1882  * - decoding: unused
1883  */
1885 
1886  /**
1887  * temporary complexity masking (0-> disabled)
1888  * - encoding: Set by user.
1889  * - decoding: unused
1890  */
1892 
1893  /**
1894  * spatial complexity masking (0-> disabled)
1895  * - encoding: Set by user.
1896  * - decoding: unused
1897  */
1899 
1900  /**
1901  * p block masking (0-> disabled)
1902  * - encoding: Set by user.
1903  * - decoding: unused
1904  */
1905  float p_masking;
1906 
1907  /**
1908  * darkness masking (0-> disabled)
1909  * - encoding: Set by user.
1910  * - decoding: unused
1911  */
1913 
1914  /**
1915  * slice count
1916  * - encoding: Set by libavcodec.
1917  * - decoding: Set by user (or 0).
1918  */
1920 
1921 #if FF_API_PRIVATE_OPT
1922  /** @deprecated use encoder private options instead */
1925 #define FF_PRED_LEFT 0
1926 #define FF_PRED_PLANE 1
1927 #define FF_PRED_MEDIAN 2
1928 #endif
1929 
1930  /**
1931  * slice offsets in the frame in bytes
1932  * - encoding: Set/allocated by libavcodec.
1933  * - decoding: Set/allocated by user (or NULL).
1934  */
1936 
1937  /**
1938  * sample aspect ratio (0 if unknown)
1939  * That is the width of a pixel divided by the height of the pixel.
1940  * Numerator and denominator must be relatively prime and smaller than 256 for some video standards.
1941  * - encoding: Set by user.
1942  * - decoding: Set by libavcodec.
1943  */
1945 
1946  /**
1947  * motion estimation comparison function
1948  * - encoding: Set by user.
1949  * - decoding: unused
1950  */
1951  int me_cmp;
1952  /**
1953  * subpixel motion estimation comparison function
1954  * - encoding: Set by user.
1955  * - decoding: unused
1956  */
1958  /**
1959  * macroblock comparison function (not supported yet)
1960  * - encoding: Set by user.
1961  * - decoding: unused
1962  */
1963  int mb_cmp;
1964  /**
1965  * interlaced DCT comparison function
1966  * - encoding: Set by user.
1967  * - decoding: unused
1968  */
1970 #define FF_CMP_SAD 0
1971 #define FF_CMP_SSE 1
1972 #define FF_CMP_SATD 2
1973 #define FF_CMP_DCT 3
1974 #define FF_CMP_PSNR 4
1975 #define FF_CMP_BIT 5
1976 #define FF_CMP_RD 6
1977 #define FF_CMP_ZERO 7
1978 #define FF_CMP_VSAD 8
1979 #define FF_CMP_VSSE 9
1980 #define FF_CMP_NSSE 10
1981 #define FF_CMP_W53 11
1982 #define FF_CMP_W97 12
1983 #define FF_CMP_DCTMAX 13
1984 #define FF_CMP_DCT264 14
1985 #define FF_CMP_MEDIAN_SAD 15
1986 #define FF_CMP_CHROMA 256
1987 
1988  /**
1989  * ME diamond size & shape
1990  * - encoding: Set by user.
1991  * - decoding: unused
1992  */
1994 
1995  /**
1996  * amount of previous MV predictors (2a+1 x 2a+1 square)
1997  * - encoding: Set by user.
1998  * - decoding: unused
1999  */
2001 
2002 #if FF_API_PRIVATE_OPT
2003  /** @deprecated use encoder private options instead */
2005  int pre_me;
2006 #endif
2007 
2008  /**
2009  * motion estimation prepass comparison function
2010  * - encoding: Set by user.
2011  * - decoding: unused
2012  */
2014 
2015  /**
2016  * ME prepass diamond size & shape
2017  * - encoding: Set by user.
2018  * - decoding: unused
2019  */
2021 
2022  /**
2023  * subpel ME quality
2024  * - encoding: Set by user.
2025  * - decoding: unused
2026  */
2028 
2029  /**
2030  * maximum motion estimation search range in subpel units
2031  * If 0 then no limit.
2032  *
2033  * - encoding: Set by user.
2034  * - decoding: unused
2035  */
2037 
2038  /**
2039  * slice flags
2040  * - encoding: unused
2041  * - decoding: Set by user.
2042  */
2044 #define SLICE_FLAG_CODED_ORDER 0x0001 ///< draw_horiz_band() is called in coded order instead of display
2045 #define SLICE_FLAG_ALLOW_FIELD 0x0002 ///< allow draw_horiz_band() with field slices (MPEG-2 field pics)
2046 #define SLICE_FLAG_ALLOW_PLANE 0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)
2047 
2048  /**
2049  * macroblock decision mode
2050  * - encoding: Set by user.
2051  * - decoding: unused
2052  */
2054 #define FF_MB_DECISION_SIMPLE 0 ///< uses mb_cmp
2055 #define FF_MB_DECISION_BITS 1 ///< chooses the one which needs the fewest bits
2056 #define FF_MB_DECISION_RD 2 ///< rate distortion
2057 
2058  /**
2059  * custom intra quantization matrix
2060  * Must be allocated with the av_malloc() family of functions, and will be freed in
2061  * avcodec_free_context().
2062  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
2063  * - decoding: Set/allocated/freed by libavcodec.
2064  */
2065  uint16_t *intra_matrix;
2066 
2067  /**
2068  * custom inter quantization matrix
2069  * Must be allocated with the av_malloc() family of functions, and will be freed in
2070  * avcodec_free_context().
2071  * - encoding: Set/allocated by user, freed by libavcodec. Can be NULL.
2072  * - decoding: Set/allocated/freed by libavcodec.
2073  */
2074  uint16_t *inter_matrix;
2075 
2076 #if FF_API_PRIVATE_OPT
2077  /** @deprecated use encoder private options instead */
2080 
2081  /** @deprecated use encoder private options instead */
2084 #endif
2085 
2086  /**
2087  * precision of the intra DC coefficient - 8
2088  * - encoding: Set by user.
2089  * - decoding: Set by libavcodec
2090  */
2092 
2093  /**
2094  * Number of macroblock rows at the top which are skipped.
2095  * - encoding: unused
2096  * - decoding: Set by user.
2097  */
2099 
2100  /**
2101  * Number of macroblock rows at the bottom which are skipped.
2102  * - encoding: unused
2103  * - decoding: Set by user.
2104  */
2106 
2107  /**
2108  * minimum MB Lagrange multiplier
2109  * - encoding: Set by user.
2110  * - decoding: unused
2111  */
2112  int mb_lmin;
2113 
2114  /**
2115  * maximum MB Lagrange multiplier
2116  * - encoding: Set by user.
2117  * - decoding: unused
2118  */
2119  int mb_lmax;
2120 
2121 #if FF_API_PRIVATE_OPT
2122  /**
2123  * @deprecated use encoder private options instead
2124  */
2127 #endif
2128 
2129  /**
2130  * - encoding: Set by user.
2131  * - decoding: unused
2132  */
2134 
2135 #if FF_API_PRIVATE_OPT
2136  /** @deprecated use encoder private options instead */
2139 #endif
2140 
2141  /**
2142  * minimum GOP size
2143  * - encoding: Set by user.
2144  * - decoding: unused
2145  */
2147 
2148  /**
2149  * number of reference frames
2150  * - encoding: Set by user.
2151  * - decoding: Set by lavc.
2152  */
2153  int refs;
2154 
2155 #if FF_API_PRIVATE_OPT
2156  /** @deprecated use encoder private options instead */
2159 #endif
2160 
2161  /**
2162  * Note: Value depends upon the compare function used for fullpel ME.
2163  * - encoding: Set by user.
2164  * - decoding: unused
2165  */
2167 
2168 #if FF_API_PRIVATE_OPT
2169  /** @deprecated use encoder private options instead */
2172 #endif
2173 
2174  /**
2175  * Chromaticity coordinates of the source primaries.
2176  * - encoding: Set by user
2177  * - decoding: Set by libavcodec
2178  */
2180 
2181  /**
2182  * Color Transfer Characteristic.
2183  * - encoding: Set by user
2184  * - decoding: Set by libavcodec
2185  */
2187 
2188  /**
2189  * YUV colorspace type.
2190  * - encoding: Set by user
2191  * - decoding: Set by libavcodec
2192  */
2194 
2195  /**
2196  * MPEG vs JPEG YUV range.
2197  * - encoding: Set by user
2198  * - decoding: Set by libavcodec
2199  */
2201 
2202  /**
2203  * This defines the location of chroma samples.
2204  * - encoding: Set by user
2205  * - decoding: Set by libavcodec
2206  */
2208 
2209  /**
2210  * Number of slices.
2211  * Indicates number of picture subdivisions. Used for parallelized
2212  * decoding.
2213  * - encoding: Set by user
2214  * - decoding: unused
2215  */
2216  int slices;
2217 
2218  /** Field order
2219  * - encoding: set by libavcodec
2220  * - decoding: Set by user.
2221  */
2223 
2224  /* audio only */
2225  int sample_rate; ///< samples per second
2226  int channels; ///< number of audio channels
2227 
2228  /**
2229  * audio sample format
2230  * - encoding: Set by user.
2231  * - decoding: Set by libavcodec.
2232  */
2233  enum AVSampleFormat sample_fmt; ///< sample format
2234 
2235  /* The following data should not be initialized. */
2236  /**
2237  * Number of samples per channel in an audio frame.
2238  *
2239  * - encoding: set by libavcodec in avcodec_open2(). Each submitted frame
2240  * except the last must contain exactly frame_size samples per channel.
2241  * May be 0 when the codec has AV_CODEC_CAP_VARIABLE_FRAME_SIZE set, then the
2242  * frame size is not restricted.
2243  * - decoding: may be set by some decoders to indicate constant frame size
2244  */
2246 
2247  /**
2248  * Frame counter, set by libavcodec.
2249  *
2250  * - decoding: total number of frames returned from the decoder so far.
2251  * - encoding: total number of frames passed to the encoder so far.
2252  *
2253  * @note the counter is not incremented if encoding/decoding resulted in
2254  * an error.
2255  */
2257 
2258  /**
2259  * number of bytes per packet if constant and known or 0
2260  * Used by some WAV based audio codecs.
2261  */
2263 
2264  /**
2265  * Audio cutoff bandwidth (0 means "automatic")
2266  * - encoding: Set by user.
2267  * - decoding: unused
2268  */
2269  int cutoff;
2270 
2271  /**
2272  * Audio channel layout.
2273  * - encoding: set by user.
2274  * - decoding: set by user, may be overwritten by libavcodec.
2275  */
2276  uint64_t channel_layout;
2277 
2278  /**
2279  * Request decoder to use this channel layout if it can (0 for default)
2280  * - encoding: unused
2281  * - decoding: Set by user.
2282  */
2284 
2285  /**
2286  * Type of service that the audio stream conveys.
2287  * - encoding: Set by user.
2288  * - decoding: Set by libavcodec.
2289  */
2291 
2292  /**
2293  * desired sample format
2294  * - encoding: Not used.
2295  * - decoding: Set by user.
2296  * Decoder will decode to this format if it can.
2297  */
2299 
2300  /**
2301  * This callback is called at the beginning of each frame to get data
2302  * buffer(s) for it. There may be one contiguous buffer for all the data or
2303  * there may be a buffer per each data plane or anything in between. What
2304  * this means is, you may set however many entries in buf[] you feel necessary.
2305  * Each buffer must be reference-counted using the AVBuffer API (see description
2306  * of buf[] below).
2307  *
2308  * The following fields will be set in the frame before this callback is
2309  * called:
2310  * - format
2311  * - width, height (video only)
2312  * - sample_rate, channel_layout, nb_samples (audio only)
2313  * Their values may differ from the corresponding values in
2314  * AVCodecContext. This callback must use the frame values, not the codec
2315  * context values, to calculate the required buffer size.
2316  *
2317  * This callback must fill the following fields in the frame:
2318  * - data[]
2319  * - linesize[]
2320  * - extended_data:
2321  * * if the data is planar audio with more than 8 channels, then this
2322  * callback must allocate and fill extended_data to contain all pointers
2323  * to all data planes. data[] must hold as many pointers as it can.
2324  * extended_data must be allocated with av_malloc() and will be freed in
2325  * av_frame_unref().
2326  * * otherwise extended_data must point to data
2327  * - buf[] must contain one or more pointers to AVBufferRef structures. Each of
2328  * the frame's data and extended_data pointers must be contained in these. That
2329  * is, one AVBufferRef for each allocated chunk of memory, not necessarily one
2330  * AVBufferRef per data[] entry. See: av_buffer_create(), av_buffer_alloc(),
2331  * and av_buffer_ref().
2332  * - extended_buf and nb_extended_buf must be allocated with av_malloc() by
2333  * this callback and filled with the extra buffers if there are more
2334  * buffers than buf[] can hold. extended_buf will be freed in
2335  * av_frame_unref().
2336  *
2337  * If AV_CODEC_CAP_DR1 is not set then get_buffer2() must call
2338  * avcodec_default_get_buffer2() instead of providing buffers allocated by
2339  * some other means.
2340  *
2341  * Each data plane must be aligned to the maximum required by the target
2342  * CPU.
2343  *
2344  * @see avcodec_default_get_buffer2()
2345  *
2346  * Video:
2347  *
2348  * If AV_GET_BUFFER_FLAG_REF is set in flags then the frame may be reused
2349  * (read and/or written to if it is writable) later by libavcodec.
2350  *
2351  * avcodec_align_dimensions2() should be used to find the required width and
2352  * height, as they normally need to be rounded up to the next multiple of 16.
2353  *
2354  * Some decoders do not support linesizes changing between frames.
2355  *
2356  * If frame multithreading is used and thread_safe_callbacks is set,
2357  * this callback may be called from a different thread, but not from more
2358  * than one at once. Does not need to be reentrant.
2359  *
2360  * @see avcodec_align_dimensions2()
2361  *
2362  * Audio:
2363  *
2364  * Decoders request a buffer of a particular size by setting
2365  * AVFrame.nb_samples prior to calling get_buffer2(). The decoder may,
2366  * however, utilize only part of the buffer by setting AVFrame.nb_samples
2367  * to a smaller value in the output frame.
2368  *
2369  * As a convenience, av_samples_get_buffer_size() and
2370  * av_samples_fill_arrays() in libavutil may be used by custom get_buffer2()
2371  * functions to find the required data size and to fill data pointers and
2372  * linesize. In AVFrame.linesize, only linesize[0] may be set for audio
2373  * since all planes must be the same size.
2374  *
2375  * @see av_samples_get_buffer_size(), av_samples_fill_arrays()
2376  *
2377  * - encoding: unused
2378  * - decoding: Set by libavcodec, user can override.
2379  */
2381 
2382  /**
2383  * If non-zero, the decoded audio and video frames returned from
2384  * avcodec_decode_video2() and avcodec_decode_audio4() are reference-counted
2385  * and are valid indefinitely. The caller must free them with
2386  * av_frame_unref() when they are not needed anymore.
2387  * Otherwise, the decoded frames must not be freed by the caller and are
2388  * only valid until the next decode call.
2389  *
2390  * This is always automatically enabled if avcodec_receive_frame() is used.
2391  *
2392  * - encoding: unused
2393  * - decoding: set by the caller before avcodec_open2().
2394  */
2397 
2398  /* - encoding parameters */
2399  float qcompress; ///< amount of qscale change between easy & hard scenes (0.0-1.0)
2400  float qblur; ///< amount of qscale smoothing over time (0.0-1.0)
2401 
2402  /**
2403  * minimum quantizer
2404  * - encoding: Set by user.
2405  * - decoding: unused
2406  */
2407  int qmin;
2408 
2409  /**
2410  * maximum quantizer
2411  * - encoding: Set by user.
2412  * - decoding: unused
2413  */
2414  int qmax;
2415 
2416  /**
2417  * maximum quantizer difference between frames
2418  * - encoding: Set by user.
2419  * - decoding: unused
2420  */
2422 
2423  /**
2424  * decoder bitstream buffer size
2425  * - encoding: Set by user.
2426  * - decoding: unused
2427  */
2429 
2430  /**
2431  * ratecontrol override, see RcOverride
2432  * - encoding: Allocated/set/freed by user.
2433  * - decoding: unused
2434  */
2437 
2438  /**
2439  * maximum bitrate
2440  * - encoding: Set by user.
2441  * - decoding: Set by user, may be overwritten by libavcodec.
2442  */
2443  int64_t rc_max_rate;
2444 
2445  /**
2446  * minimum bitrate
2447  * - encoding: Set by user.
2448  * - decoding: unused
2449  */
2450  int64_t rc_min_rate;
2451 
2452  /**
2453  * Ratecontrol attempt to use, at maximum, <value> of what can be used without an underflow.
2454  * - encoding: Set by user.
2455  * - decoding: unused.
2456  */
2458 
2459  /**
2460  * Ratecontrol attempt to use, at least, <value> times the amount needed to prevent a vbv overflow.
2461  * - encoding: Set by user.
2462  * - decoding: unused.
2463  */
2465 
2466  /**
2467  * Number of bits which should be loaded into the rc buffer before decoding starts.
2468  * - encoding: Set by user.
2469  * - decoding: unused
2470  */
2472 
2473 #if FF_API_CODER_TYPE
2474 #define FF_CODER_TYPE_VLC 0
2475 #define FF_CODER_TYPE_AC 1
2476 #define FF_CODER_TYPE_RAW 2
2477 #define FF_CODER_TYPE_RLE 3
2478  /**
2479  * @deprecated use encoder private options instead
2480  */
2483 #endif /* FF_API_CODER_TYPE */
2484 
2485 #if FF_API_PRIVATE_OPT
2486  /** @deprecated use encoder private options instead */
2489 #endif
2490 
2491 #if FF_API_PRIVATE_OPT
2492  /** @deprecated use encoder private options instead */
2495 
2496  /** @deprecated use encoder private options instead */
2499 
2500  /** @deprecated use encoder private options instead */
2503 
2504  /** @deprecated use encoder private options instead */
2507 #endif /* FF_API_PRIVATE_OPT */
2508 
2509  /**
2510  * trellis RD quantization
2511  * - encoding: Set by user.
2512  * - decoding: unused
2513  */
2514  int trellis;
2515 
2516 #if FF_API_PRIVATE_OPT
2517  /** @deprecated use encoder private options instead */
2520 
2521  /** @deprecated use encoder private options instead */
2524 
2525  /** @deprecated use encoder private options instead */
2528 #endif
2529 
2530 #if FF_API_RTP_CALLBACK
2531  /**
2532  * @deprecated unused
2533  */
2534  /* The RTP callback: This function is called */
2535  /* every time the encoder has a packet to send. */
2536  /* It depends on the encoder if the data starts */
2537  /* with a Start Code (it should). H.263 does. */
2538  /* mb_nb contains the number of macroblocks */
2539  /* encoded in the RTP payload. */
2541  void (*rtp_callback)(struct AVCodecContext *avctx, void *data, int size, int mb_nb);
2542 #endif
2543 
2544 #if FF_API_PRIVATE_OPT
2545  /** @deprecated use encoder private options instead */
2547  int rtp_payload_size; /* The size of the RTP payload: the coder will */
2548  /* do its best to deliver a chunk with size */
2549  /* below rtp_payload_size, the chunk will start */
2550  /* with a start code on some codecs like H.263. */
2551  /* This doesn't take account of any particular */
2552  /* headers inside the transmitted RTP payload. */
2553 #endif
2554 
2555 #if FF_API_STAT_BITS
2556  /* statistics, used for 2-pass encoding */
2558  int mv_bits;
2566  int i_count;
2568  int p_count;
2573 
2574  /** @deprecated this field is unused */
2577 #endif
2578 
2579  /**
2580  * pass1 encoding statistics output buffer
2581  * - encoding: Set by libavcodec.
2582  * - decoding: unused
2583  */
2584  char *stats_out;
2585 
2586  /**
2587  * pass2 encoding statistics input buffer
2588  * Concatenated stuff from stats_out of pass1 should be placed here.
2589  * - encoding: Allocated/set/freed by user.
2590  * - decoding: unused
2591  */
2592  char *stats_in;
2593 
2594  /**
2595  * Work around bugs in encoders which sometimes cannot be detected automatically.
2596  * - encoding: Set by user
2597  * - decoding: Set by user
2598  */
2600 #define FF_BUG_AUTODETECT 1 ///< autodetection
2601 #define FF_BUG_XVID_ILACE 4
2602 #define FF_BUG_UMP4 8
2603 #define FF_BUG_NO_PADDING 16
2604 #define FF_BUG_AMV 32
2605 #define FF_BUG_QPEL_CHROMA 64
2606 #define FF_BUG_STD_QPEL 128
2607 #define FF_BUG_QPEL_CHROMA2 256
2608 #define FF_BUG_DIRECT_BLOCKSIZE 512
2609 #define FF_BUG_EDGE 1024
2610 #define FF_BUG_HPEL_CHROMA 2048
2611 #define FF_BUG_DC_CLIP 4096
2612 #define FF_BUG_MS 8192 ///< Work around various bugs in Microsoft's broken decoders.
2613 #define FF_BUG_TRUNCATED 16384
2614 #define FF_BUG_IEDGE 32768
2615 
2616  /**
2617  * strictly follow the standard (MPEG-4, ...).
2618  * - encoding: Set by user.
2619  * - decoding: Set by user.
2620  * Setting this to STRICT or higher means the encoder and decoder will
2621  * generally do stupid things, whereas setting it to unofficial or lower
2622  * will mean the encoder might produce output that is not supported by all
2623  * spec-compliant decoders. Decoders don't differentiate between normal,
2624  * unofficial and experimental (that is, they always try to decode things
2625  * when they can) unless they are explicitly asked to behave stupidly
2626  * (=strictly conform to the specs)
2627  */
2629 #define FF_COMPLIANCE_VERY_STRICT 2 ///< Strictly conform to an older more strict version of the spec or reference software.
2630 #define FF_COMPLIANCE_STRICT 1 ///< Strictly conform to all the things in the spec no matter what consequences.
2631 #define FF_COMPLIANCE_NORMAL 0
2632 #define FF_COMPLIANCE_UNOFFICIAL -1 ///< Allow unofficial extensions
2633 #define FF_COMPLIANCE_EXPERIMENTAL -2 ///< Allow nonstandardized experimental things.
2634 
2635  /**
2636  * error concealment flags
2637  * - encoding: unused
2638  * - decoding: Set by user.
2639  */
2641 #define FF_EC_GUESS_MVS 1
2642 #define FF_EC_DEBLOCK 2
2643 #define FF_EC_FAVOR_INTER 256
2644 
2645  /**
2646  * debug
2647  * - encoding: Set by user.
2648  * - decoding: Set by user.
2649  */
2650  int debug;
2651 #define FF_DEBUG_PICT_INFO 1
2652 #define FF_DEBUG_RC 2
2653 #define FF_DEBUG_BITSTREAM 4
2654 #define FF_DEBUG_MB_TYPE 8
2655 #define FF_DEBUG_QP 16
2656 #if FF_API_DEBUG_MV
2657 /**
2658  * @deprecated this option does nothing
2659  */
2660 #define FF_DEBUG_MV 32
2661 #endif
2662 #define FF_DEBUG_DCT_COEFF 0x00000040
2663 #define FF_DEBUG_SKIP 0x00000080
2664 #define FF_DEBUG_STARTCODE 0x00000100
2665 #define FF_DEBUG_ER 0x00000400
2666 #define FF_DEBUG_MMCO 0x00000800
2667 #define FF_DEBUG_BUGS 0x00001000
2668 #if FF_API_DEBUG_MV
2669 #define FF_DEBUG_VIS_QP 0x00002000
2670 #define FF_DEBUG_VIS_MB_TYPE 0x00004000
2671 #endif
2672 #define FF_DEBUG_BUFFERS 0x00008000
2673 #define FF_DEBUG_THREADS 0x00010000
2674 #define FF_DEBUG_GREEN_MD 0x00800000
2675 #define FF_DEBUG_NOMC 0x01000000
2676 
2677 #if FF_API_DEBUG_MV
2678  /**
2679  * debug
2680  * - encoding: Set by user.
2681  * - decoding: Set by user.
2682  */
2683  int debug_mv;
2684 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 // visualize forward predicted MVs of P-frames
2685 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 // visualize forward predicted MVs of B-frames
2686 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 // visualize backward predicted MVs of B-frames
2687 #endif
2688 
2689  /**
2690  * Error recognition; may misdetect some more or less valid parts as errors.
2691  * - encoding: unused
2692  * - decoding: Set by user.
2693  */
2695 
2696 /**
2697  * Verify checksums embedded in the bitstream (could be of either encoded or
2698  * decoded data, depending on the codec) and print an error message on mismatch.
2699  * If AV_EF_EXPLODE is also set, a mismatching checksum will result in the
2700  * decoder returning an error.
2701  */
2702 #define AV_EF_CRCCHECK (1<<0)
2703 #define AV_EF_BITSTREAM (1<<1) ///< detect bitstream specification deviations
2704 #define AV_EF_BUFFER (1<<2) ///< detect improper bitstream length
2705 #define AV_EF_EXPLODE (1<<3) ///< abort decoding on minor error detection
2706 
2707 #define AV_EF_IGNORE_ERR (1<<15) ///< ignore errors and continue
2708 #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
2709 #define AV_EF_COMPLIANT (1<<17) ///< consider all spec non compliances as errors
2710 #define AV_EF_AGGRESSIVE (1<<18) ///< consider things that a sane encoder should not do as an error
2711 
2712 
2713  /**
2714  * opaque 64-bit number (generally a PTS) that will be reordered and
2715  * output in AVFrame.reordered_opaque
2716  * - encoding: Set by libavcodec to the reordered_opaque of the input
2717  * frame corresponding to the last returned packet. Only
2718  * supported by encoders with the
2719  * AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE capability.
2720  * - decoding: Set by user.
2721  */
2723 
2724  /**
2725  * Hardware accelerator in use
2726  * - encoding: unused.
2727  * - decoding: Set by libavcodec
2728  */
2729  const struct AVHWAccel *hwaccel;
2730 
2731  /**
2732  * Hardware accelerator context.
2733  * For some hardware accelerators, a global context needs to be
2734  * provided by the user. In that case, this holds display-dependent
2735  * data FFmpeg cannot instantiate itself. Please refer to the
2736  * FFmpeg HW accelerator documentation to know how to fill this
2737  * is. e.g. for VA API, this is a struct vaapi_context.
2738  * - encoding: unused
2739  * - decoding: Set by user
2740  */
2742 
2743  /**
2744  * error
2745  * - encoding: Set by libavcodec if flags & AV_CODEC_FLAG_PSNR.
2746  * - decoding: unused
2747  */
2749 
2750  /**
2751  * DCT algorithm, see FF_DCT_* below
2752  * - encoding: Set by user.
2753  * - decoding: unused
2754  */
2756 #define FF_DCT_AUTO 0
2757 #define FF_DCT_FASTINT 1
2758 #define FF_DCT_INT 2
2759 #define FF_DCT_MMX 3
2760 #define FF_DCT_ALTIVEC 5
2761 #define FF_DCT_FAAN 6
2762 
2763  /**
2764  * IDCT algorithm, see FF_IDCT_* below.
2765  * - encoding: Set by user.
2766  * - decoding: Set by user.
2767  */
2769 #define FF_IDCT_AUTO 0
2770 #define FF_IDCT_INT 1
2771 #define FF_IDCT_SIMPLE 2
2772 #define FF_IDCT_SIMPLEMMX 3
2773 #define FF_IDCT_ARM 7
2774 #define FF_IDCT_ALTIVEC 8
2775 #define FF_IDCT_SIMPLEARM 10
2776 #define FF_IDCT_XVID 14
2777 #define FF_IDCT_SIMPLEARMV5TE 16
2778 #define FF_IDCT_SIMPLEARMV6 17
2779 #define FF_IDCT_FAAN 20
2780 #define FF_IDCT_SIMPLENEON 22
2781 #define FF_IDCT_NONE 24 /* Used by XvMC to extract IDCT coefficients with FF_IDCT_PERM_NONE */
2782 #define FF_IDCT_SIMPLEAUTO 128
2783 
2784  /**
2785  * bits per sample/pixel from the demuxer (needed for huffyuv).
2786  * - encoding: Set by libavcodec.
2787  * - decoding: Set by user.
2788  */
2790 
2791  /**
2792  * Bits per sample/pixel of internal libavcodec pixel/sample format.
2793  * - encoding: set by user.
2794  * - decoding: set by libavcodec.
2795  */
2797 
2798 #if FF_API_LOWRES
2799  /**
2800  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
2801  * - encoding: unused
2802  * - decoding: Set by user.
2803  */
2804  int lowres;
2805 #endif
2806 
2807 #if FF_API_CODED_FRAME
2808  /**
2809  * the picture in the bitstream
2810  * - encoding: Set by libavcodec.
2811  * - decoding: unused
2812  *
2813  * @deprecated use the quality factor packet side data instead
2814  */
2816 #endif
2817 
2818  /**
2819  * thread count
2820  * is used to decide how many independent tasks should be passed to execute()
2821  * - encoding: Set by user.
2822  * - decoding: Set by user.
2823  */
2825 
2826  /**
2827  * Which multithreading methods to use.
2828  * Use of FF_THREAD_FRAME will increase decoding delay by one frame per thread,
2829  * so clients which cannot provide future frames should not use it.
2830  *
2831  * - encoding: Set by user, otherwise the default is used.
2832  * - decoding: Set by user, otherwise the default is used.
2833  */
2835 #define FF_THREAD_FRAME 1 ///< Decode more than one frame at once
2836 #define FF_THREAD_SLICE 2 ///< Decode more than one part of a single frame at once
2837 
2838  /**
2839  * Which multithreading methods are in use by the codec.
2840  * - encoding: Set by libavcodec.
2841  * - decoding: Set by libavcodec.
2842  */
2844 
2845  /**
2846  * Set by the client if its custom get_buffer() callback can be called
2847  * synchronously from another thread, which allows faster multithreaded decoding.
2848  * draw_horiz_band() will be called from other threads regardless of this setting.
2849  * Ignored if the default get_buffer() is used.
2850  * - encoding: Set by user.
2851  * - decoding: Set by user.
2852  */
2854 
2855  /**
2856  * The codec may call this to execute several independent things.
2857  * It will return only after finishing all tasks.
2858  * The user may replace this with some multithreaded implementation,
2859  * the default implementation will execute the parts serially.
2860  * @param count the number of things to execute
2861  * - encoding: Set by libavcodec, user can override.
2862  * - decoding: Set by libavcodec, user can override.
2863  */
2864  int (*execute)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg), void *arg2, int *ret, int count, int size);
2865 
2866  /**
2867  * The codec may call this to execute several independent things.
2868  * It will return only after finishing all tasks.
2869  * The user may replace this with some multithreaded implementation,
2870  * the default implementation will execute the parts serially.
2871  * Also see avcodec_thread_init and e.g. the --enable-pthread configure option.
2872  * @param c context passed also to func
2873  * @param count the number of things to execute
2874  * @param arg2 argument passed unchanged to func
2875  * @param ret return values of executed functions, must have space for "count" values. May be NULL.
2876  * @param func function that will be called count times, with jobnr from 0 to count-1.
2877  * threadnr will be in the range 0 to c->thread_count-1 < MAX_THREADS and so that no
2878  * two instances of func executing at the same time will have the same threadnr.
2879  * @return always 0 currently, but code should handle a future improvement where when any call to func
2880  * returns < 0 no further calls to func may be done and < 0 is returned.
2881  * - encoding: Set by libavcodec, user can override.
2882  * - decoding: Set by libavcodec, user can override.
2883  */
2884  int (*execute2)(struct AVCodecContext *c, int (*func)(struct AVCodecContext *c2, void *arg, int jobnr, int threadnr), void *arg2, int *ret, int count);
2885 
2886  /**
2887  * noise vs. sse weight for the nsse comparison function
2888  * - encoding: Set by user.
2889  * - decoding: unused
2890  */
2892 
2893  /**
2894  * profile
2895  * - encoding: Set by user.
2896  * - decoding: Set by libavcodec.
2897  */
2898  int profile;
2899 #define FF_PROFILE_UNKNOWN -99
2900 #define FF_PROFILE_RESERVED -100
2901 
2902 #define FF_PROFILE_AAC_MAIN 0
2903 #define FF_PROFILE_AAC_LOW 1
2904 #define FF_PROFILE_AAC_SSR 2
2905 #define FF_PROFILE_AAC_LTP 3
2906 #define FF_PROFILE_AAC_HE 4
2907 #define FF_PROFILE_AAC_HE_V2 28
2908 #define FF_PROFILE_AAC_LD 22
2909 #define FF_PROFILE_AAC_ELD 38
2910 #define FF_PROFILE_MPEG2_AAC_LOW 128
2911 #define FF_PROFILE_MPEG2_AAC_HE 131
2912 
2913 #define FF_PROFILE_DNXHD 0
2914 #define FF_PROFILE_DNXHR_LB 1
2915 #define FF_PROFILE_DNXHR_SQ 2
2916 #define FF_PROFILE_DNXHR_HQ 3
2917 #define FF_PROFILE_DNXHR_HQX 4
2918 #define FF_PROFILE_DNXHR_444 5
2919 
2920 #define FF_PROFILE_DTS 20
2921 #define FF_PROFILE_DTS_ES 30
2922 #define FF_PROFILE_DTS_96_24 40
2923 #define FF_PROFILE_DTS_HD_HRA 50
2924 #define FF_PROFILE_DTS_HD_MA 60
2925 #define FF_PROFILE_DTS_EXPRESS 70
2926 
2927 #define FF_PROFILE_MPEG2_422 0
2928 #define FF_PROFILE_MPEG2_HIGH 1
2929 #define FF_PROFILE_MPEG2_SS 2
2930 #define FF_PROFILE_MPEG2_SNR_SCALABLE 3
2931 #define FF_PROFILE_MPEG2_MAIN 4
2932 #define FF_PROFILE_MPEG2_SIMPLE 5
2933 
2934 #define FF_PROFILE_H264_CONSTRAINED (1<<9) // 8+1; constraint_set1_flag
2935 #define FF_PROFILE_H264_INTRA (1<<11) // 8+3; constraint_set3_flag
2936 
2937 #define FF_PROFILE_H264_BASELINE 66
2938 #define FF_PROFILE_H264_CONSTRAINED_BASELINE (66|FF_PROFILE_H264_CONSTRAINED)
2939 #define FF_PROFILE_H264_MAIN 77
2940 #define FF_PROFILE_H264_EXTENDED 88
2941 #define FF_PROFILE_H264_HIGH 100
2942 #define FF_PROFILE_H264_HIGH_10 110
2943 #define FF_PROFILE_H264_HIGH_10_INTRA (110|FF_PROFILE_H264_INTRA)
2944 #define FF_PROFILE_H264_MULTIVIEW_HIGH 118
2945 #define FF_PROFILE_H264_HIGH_422 122
2946 #define FF_PROFILE_H264_HIGH_422_INTRA (122|FF_PROFILE_H264_INTRA)
2947 #define FF_PROFILE_H264_STEREO_HIGH 128
2948 #define FF_PROFILE_H264_HIGH_444 144
2949 #define FF_PROFILE_H264_HIGH_444_PREDICTIVE 244
2950 #define FF_PROFILE_H264_HIGH_444_INTRA (244|FF_PROFILE_H264_INTRA)
2951 #define FF_PROFILE_H264_CAVLC_444 44
2952 
2953 #define FF_PROFILE_VC1_SIMPLE 0
2954 #define FF_PROFILE_VC1_MAIN 1
2955 #define FF_PROFILE_VC1_COMPLEX 2
2956 #define FF_PROFILE_VC1_ADVANCED 3
2957 
2958 #define FF_PROFILE_MPEG4_SIMPLE 0
2959 #define FF_PROFILE_MPEG4_SIMPLE_SCALABLE 1
2960 #define FF_PROFILE_MPEG4_CORE 2
2961 #define FF_PROFILE_MPEG4_MAIN 3
2962 #define FF_PROFILE_MPEG4_N_BIT 4
2963 #define FF_PROFILE_MPEG4_SCALABLE_TEXTURE 5
2964 #define FF_PROFILE_MPEG4_SIMPLE_FACE_ANIMATION 6
2965 #define FF_PROFILE_MPEG4_BASIC_ANIMATED_TEXTURE 7
2966 #define FF_PROFILE_MPEG4_HYBRID 8
2967 #define FF_PROFILE_MPEG4_ADVANCED_REAL_TIME 9
2968 #define FF_PROFILE_MPEG4_CORE_SCALABLE 10
2969 #define FF_PROFILE_MPEG4_ADVANCED_CODING 11
2970 #define FF_PROFILE_MPEG4_ADVANCED_CORE 12
2971 #define FF_PROFILE_MPEG4_ADVANCED_SCALABLE_TEXTURE 13
2972 #define FF_PROFILE_MPEG4_SIMPLE_STUDIO 14
2973 #define FF_PROFILE_MPEG4_ADVANCED_SIMPLE 15
2974 
2975 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_0 1
2976 #define FF_PROFILE_JPEG2000_CSTREAM_RESTRICTION_1 2
2977 #define FF_PROFILE_JPEG2000_CSTREAM_NO_RESTRICTION 32768
2978 #define FF_PROFILE_JPEG2000_DCINEMA_2K 3
2979 #define FF_PROFILE_JPEG2000_DCINEMA_4K 4
2980 
2981 #define FF_PROFILE_VP9_0 0
2982 #define FF_PROFILE_VP9_1 1
2983 #define FF_PROFILE_VP9_2 2
2984 #define FF_PROFILE_VP9_3 3
2985 
2986 #define FF_PROFILE_HEVC_MAIN 1
2987 #define FF_PROFILE_HEVC_MAIN_10 2
2988 #define FF_PROFILE_HEVC_MAIN_STILL_PICTURE 3
2989 #define FF_PROFILE_HEVC_REXT 4
2990 
2991 #define FF_PROFILE_AV1_MAIN 0
2992 #define FF_PROFILE_AV1_HIGH 1
2993 #define FF_PROFILE_AV1_PROFESSIONAL 2
2994 
2995 #define FF_PROFILE_MJPEG_HUFFMAN_BASELINE_DCT 0xc0
2996 #define FF_PROFILE_MJPEG_HUFFMAN_EXTENDED_SEQUENTIAL_DCT 0xc1
2997 #define FF_PROFILE_MJPEG_HUFFMAN_PROGRESSIVE_DCT 0xc2
2998 #define FF_PROFILE_MJPEG_HUFFMAN_LOSSLESS 0xc3
2999 #define FF_PROFILE_MJPEG_JPEG_LS 0xf7
3000 
3001 #define FF_PROFILE_SBC_MSBC 1
3002 
3003 #define FF_PROFILE_PRORES_PROXY 0
3004 #define FF_PROFILE_PRORES_LT 1
3005 #define FF_PROFILE_PRORES_STANDARD 2
3006 #define FF_PROFILE_PRORES_HQ 3
3007 #define FF_PROFILE_PRORES_4444 4
3008 #define FF_PROFILE_PRORES_XQ 5
3009 
3010 #define FF_PROFILE_ARIB_PROFILE_A 0
3011 #define FF_PROFILE_ARIB_PROFILE_C 1
3012 
3013  /**
3014  * level
3015  * - encoding: Set by user.
3016  * - decoding: Set by libavcodec.
3017  */
3018  int level;
3019 #define FF_LEVEL_UNKNOWN -99
3020 
3021  /**
3022  * Skip loop filtering for selected frames.
3023  * - encoding: unused
3024  * - decoding: Set by user.
3025  */
3027 
3028  /**
3029  * Skip IDCT/dequantization for selected frames.
3030  * - encoding: unused
3031  * - decoding: Set by user.
3032  */
3034 
3035  /**
3036  * Skip decoding for selected frames.
3037  * - encoding: unused
3038  * - decoding: Set by user.
3039  */
3041 
3042  /**
3043  * Header containing style information for text subtitles.
3044  * For SUBTITLE_ASS subtitle type, it should contain the whole ASS
3045  * [Script Info] and [V4+ Styles] section, plus the [Events] line and
3046  * the Format line following. It shouldn't include any Dialogue line.
3047  * - encoding: Set/allocated/freed by user (before avcodec_open2())
3048  * - decoding: Set/allocated/freed by libavcodec (by avcodec_open2())
3049  */
3052 
3053 #if FF_API_VBV_DELAY
3054  /**
3055  * VBV delay coded in the last frame (in periods of a 27 MHz clock).
3056  * Used for compliant TS muxing.
3057  * - encoding: Set by libavcodec.
3058  * - decoding: unused.
3059  * @deprecated this value is now exported as a part of
3060  * AV_PKT_DATA_CPB_PROPERTIES packet side data
3061  */
3063  uint64_t vbv_delay;
3064 #endif
3065 
3066 #if FF_API_SIDEDATA_ONLY_PKT
3067  /**
3068  * Encoding only and set by default. Allow encoders to output packets
3069  * that do not contain any encoded data, only side data.
3070  *
3071  * Some encoders need to output such packets, e.g. to update some stream
3072  * parameters at the end of encoding.
3073  *
3074  * @deprecated this field disables the default behaviour and
3075  * it is kept only for compatibility.
3076  */
3079 #endif
3080 
3081  /**
3082  * Audio only. The number of "priming" samples (padding) inserted by the
3083  * encoder at the beginning of the audio. I.e. this number of leading
3084  * decoded samples must be discarded by the caller to get the original audio
3085  * without leading padding.
3086  *
3087  * - decoding: unused
3088  * - encoding: Set by libavcodec. The timestamps on the output packets are
3089  * adjusted by the encoder so that they always refer to the
3090  * first sample of the data actually contained in the packet,
3091  * including any added padding. E.g. if the timebase is
3092  * 1/samplerate and the timestamp of the first input sample is
3093  * 0, the timestamp of the first output packet will be
3094  * -initial_padding.
3095  */
3097 
3098  /**
3099  * - decoding: For codecs that store a framerate value in the compressed
3100  * bitstream, the decoder may export it here. { 0, 1} when
3101  * unknown.
3102  * - encoding: May be used to signal the framerate of CFR content to an
3103  * encoder.
3104  */
3106 
3107  /**
3108  * Nominal unaccelerated pixel format, see AV_PIX_FMT_xxx.
3109  * - encoding: unused.
3110  * - decoding: Set by libavcodec before calling get_format()
3111  */
3113 
3114  /**
3115  * Timebase in which pkt_dts/pts and AVPacket.dts/pts are.
3116  * - encoding unused.
3117  * - decoding set by user.
3118  */
3120 
3121  /**
3122  * AVCodecDescriptor
3123  * - encoding: unused.
3124  * - decoding: set by libavcodec.
3125  */
3127 
3128 #if !FF_API_LOWRES
3129  /**
3130  * low resolution decoding, 1-> 1/2 size, 2->1/4 size
3131  * - encoding: unused
3132  * - decoding: Set by user.
3133  */
3134  int lowres;
3135 #endif
3136 
3137  /**
3138  * Current statistics for PTS correction.
3139  * - decoding: maintained and used by libavcodec, not intended to be used by user apps
3140  * - encoding: unused
3141  */
3142  int64_t pts_correction_num_faulty_pts; /// Number of incorrect PTS values so far
3143  int64_t pts_correction_num_faulty_dts; /// Number of incorrect DTS values so far
3144  int64_t pts_correction_last_pts; /// PTS of the last frame
3145  int64_t pts_correction_last_dts; /// DTS of the last frame
3146 
3147  /**
3148  * Character encoding of the input subtitles file.
3149  * - decoding: set by user
3150  * - encoding: unused
3151  */
3153 
3154  /**
3155  * Subtitles character encoding mode. Formats or codecs might be adjusting
3156  * this setting (if they are doing the conversion themselves for instance).
3157  * - decoding: set by libavcodec
3158  * - encoding: unused
3159  */
3161 #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)
3162 #define FF_SUB_CHARENC_MODE_AUTOMATIC 0 ///< libavcodec will select the mode itself
3163 #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
3164 #define FF_SUB_CHARENC_MODE_IGNORE 2 ///< neither convert the subtitles, nor check them for valid UTF-8
3165 
3166  /**
3167  * Skip processing alpha if supported by codec.
3168  * Note that if the format uses pre-multiplied alpha (common with VP6,
3169  * and recommended due to better video quality/compression)
3170  * the image will look as if alpha-blended onto a black background.
3171  * However for formats that do not use pre-multiplied alpha
3172  * there might be serious artefacts (though e.g. libswscale currently
3173  * assumes pre-multiplied alpha anyway).
3174  *
3175  * - decoding: set by user
3176  * - encoding: unused
3177  */
3179 
3180  /**
3181  * Number of samples to skip after a discontinuity
3182  * - decoding: unused
3183  * - encoding: set by libavcodec
3184  */
3186 
3187 #if !FF_API_DEBUG_MV
3188  /**
3189  * debug motion vectors
3190  * - encoding: Set by user.
3191  * - decoding: Set by user.
3192  */
3194 #define FF_DEBUG_VIS_MV_P_FOR 0x00000001 //visualize forward predicted MVs of P frames
3195 #define FF_DEBUG_VIS_MV_B_FOR 0x00000002 //visualize forward predicted MVs of B frames
3196 #define FF_DEBUG_VIS_MV_B_BACK 0x00000004 //visualize backward predicted MVs of B frames
3197 #endif
3198 
3199  /**
3200  * custom intra quantization matrix
3201  * - encoding: Set by user, can be NULL.
3202  * - decoding: unused.
3203  */
3205 
3206  /**
3207  * dump format separator.
3208  * can be ", " or "\n " or anything else
3209  * - encoding: Set by user.
3210  * - decoding: Set by user.
3211  */
3213 
3214  /**
3215  * ',' separated list of allowed decoders.
3216  * If NULL then all are allowed
3217  * - encoding: unused
3218  * - decoding: set by user
3219  */
3221 
3222  /**
3223  * Properties of the stream that gets decoded
3224  * - encoding: unused
3225  * - decoding: set by libavcodec
3226  */
3227  unsigned properties;
3228 #define FF_CODEC_PROPERTY_LOSSLESS 0x00000001
3229 #define FF_CODEC_PROPERTY_CLOSED_CAPTIONS 0x00000002
3230 
3231  /**
3232  * Additional data associated with the entire coded stream.
3233  *
3234  * - decoding: unused
3235  * - encoding: may be set by libavcodec after avcodec_open2().
3236  */
3239 
3240  /**
3241  * A reference to the AVHWFramesContext describing the input (for encoding)
3242  * or output (decoding) frames. The reference is set by the caller and
3243  * afterwards owned (and freed) by libavcodec - it should never be read by
3244  * the caller after being set.
3245  *
3246  * - decoding: This field should be set by the caller from the get_format()
3247  * callback. The previous reference (if any) will always be
3248  * unreffed by libavcodec before the get_format() call.
3249  *
3250  * If the default get_buffer2() is used with a hwaccel pixel
3251  * format, then this AVHWFramesContext will be used for
3252  * allocating the frame buffers.
3253  *
3254  * - encoding: For hardware encoders configured to use a hwaccel pixel
3255  * format, this field should be set by the caller to a reference
3256  * to the AVHWFramesContext describing input frames.
3257  * AVHWFramesContext.format must be equal to
3258  * AVCodecContext.pix_fmt.
3259  *
3260  * This field should be set before avcodec_open2() is called.
3261  */
3263 
3264  /**
3265  * Control the form of AVSubtitle.rects[N]->ass
3266  * - decoding: set by user
3267  * - encoding: unused
3268  */
3270 #define FF_SUB_TEXT_FMT_ASS 0
3271 #if FF_API_ASS_TIMING
3272 #define FF_SUB_TEXT_FMT_ASS_WITH_TIMINGS 1
3273 #endif
3274 
3275  /**
3276  * Audio only. The amount of padding (in samples) appended by the encoder to
3277  * the end of the audio. I.e. this number of decoded samples must be
3278  * discarded by the caller from the end of the stream to get the original
3279  * audio without any trailing padding.
3280  *
3281  * - decoding: unused
3282  * - encoding: unused
3283  */
3285 
3286  /**
3287  * The number of pixels per image to maximally accept.
3288  *
3289  * - decoding: set by user
3290  * - encoding: set by user
3291  */
3292  int64_t max_pixels;
3293 
3294  /**
3295  * A reference to the AVHWDeviceContext describing the device which will
3296  * be used by a hardware encoder/decoder. The reference is set by the
3297  * caller and afterwards owned (and freed) by libavcodec.
3298  *
3299  * This should be used if either the codec device does not require
3300  * hardware frames or any that are used are to be allocated internally by
3301  * libavcodec. If the user wishes to supply any of the frames used as
3302  * encoder input or decoder output then hw_frames_ctx should be used
3303  * instead. When hw_frames_ctx is set in get_format() for a decoder, this
3304  * field will be ignored while decoding the associated stream segment, but
3305  * may again be used on a following one after another get_format() call.
3306  *
3307  * For both encoders and decoders this field should be set before
3308  * avcodec_open2() is called and must not be written to thereafter.
3309  *
3310  * Note that some decoders may require this field to be set initially in
3311  * order to support hw_frames_ctx at all - in that case, all frames
3312  * contexts used must be created on the same device.
3313  */
3315 
3316  /**
3317  * Bit set of AV_HWACCEL_FLAG_* flags, which affect hardware accelerated
3318  * decoding (if active).
3319  * - encoding: unused
3320  * - decoding: Set by user (either before avcodec_open2(), or in the
3321  * AVCodecContext.get_format callback)
3322  */
3324 
3325  /**
3326  * Video decoding only. Certain video codecs support cropping, meaning that
3327  * only a sub-rectangle of the decoded frame is intended for display. This
3328  * option controls how cropping is handled by libavcodec.
3329  *
3330  * When set to 1 (the default), libavcodec will apply cropping internally.
3331  * I.e. it will modify the output frame width/height fields and offset the
3332  * data pointers (only by as much as possible while preserving alignment, or
3333  * by the full amount if the AV_CODEC_FLAG_UNALIGNED flag is set) so that
3334  * the frames output by the decoder refer only to the cropped area. The
3335  * crop_* fields of the output frames will be zero.
3336  *
3337  * When set to 0, the width/height fields of the output frames will be set
3338  * to the coded dimensions and the crop_* fields will describe the cropping
3339  * rectangle. Applying the cropping is left to the caller.
3340  *
3341  * @warning When hardware acceleration with opaque output frames is used,
3342  * libavcodec is unable to apply cropping from the top/left border.
3343  *
3344  * @note when this option is set to zero, the width/height fields of the
3345  * AVCodecContext and output AVFrames have different meanings. The codec
3346  * context fields store display dimensions (with the coded dimensions in
3347  * coded_width/height), while the frame fields store the coded dimensions
3348  * (with the display dimensions being determined by the crop_* fields).
3349  */
3351 
3352  /*
3353  * Video decoding only. Sets the number of extra hardware frames which
3354  * the decoder will allocate for use by the caller. This must be set
3355  * before avcodec_open2() is called.
3356  *
3357  * Some hardware decoders require all frames that they will use for
3358  * output to be defined in advance before decoding starts. For such
3359  * decoders, the hardware frame pool must therefore be of a fixed size.
3360  * The extra frames set here are on top of any number that the decoder
3361  * needs internally in order to operate normally (for example, frames
3362  * used as reference pictures).
3363  */
3365 
3366  /**
3367  * The percentage of damaged samples to discard a frame.
3368  *
3369  * - decoding: set by user
3370  * - encoding: unused
3371  */
3373 } AVCodecContext;
3374 
3375 #if FF_API_CODEC_GET_SET
3376 /**
3377  * Accessors for some AVCodecContext fields. These used to be provided for ABI
3378  * compatibility, and do not need to be used anymore.
3379  */
3384 
3389 
3391 unsigned av_codec_get_codec_properties(const AVCodecContext *avctx);
3392 
3393 #if FF_API_LOWRES
3395 int av_codec_get_lowres(const AVCodecContext *avctx);
3397 void av_codec_set_lowres(AVCodecContext *avctx, int val);
3398 #endif
3399 
3401 int av_codec_get_seek_preroll(const AVCodecContext *avctx);
3403 void av_codec_set_seek_preroll(AVCodecContext *avctx, int val);
3404 
3406 uint16_t *av_codec_get_chroma_intra_matrix(const AVCodecContext *avctx);
3408 void av_codec_set_chroma_intra_matrix(AVCodecContext *avctx, uint16_t *val);
3409 #endif
3410 
3411 /**
3412  * AVProfile.
3413  */
3414 typedef struct AVProfile {
3415  int profile;
3416  const char *name; ///< short name for the profile
3417 } AVProfile;
3418 
3419 enum {
3420  /**
3421  * The codec supports this format via the hw_device_ctx interface.
3422  *
3423  * When selecting this format, AVCodecContext.hw_device_ctx should
3424  * have been set to a device of the specified type before calling
3425  * avcodec_open2().
3426  */
3428  /**
3429  * The codec supports this format via the hw_frames_ctx interface.
3430  *
3431  * When selecting this format for a decoder,
3432  * AVCodecContext.hw_frames_ctx should be set to a suitable frames
3433  * context inside the get_format() callback. The frames context
3434  * must have been created on a device of the specified type.
3435  */
3437  /**
3438  * The codec supports this format by some internal method.
3439  *
3440  * This format can be selected without any additional configuration -
3441  * no device or frames context is required.
3442  */
3444  /**
3445  * The codec supports this format by some ad-hoc method.
3446  *
3447  * Additional settings and/or function calls are required. See the
3448  * codec-specific documentation for details. (Methods requiring
3449  * this sort of configuration are deprecated and others should be
3450  * used in preference.)
3451  */
3453 };
3454 
3455 typedef struct AVCodecHWConfig {
3456  /**
3457  * A hardware pixel format which the codec can use.
3458  */
3460  /**
3461  * Bit set of AV_CODEC_HW_CONFIG_METHOD_* flags, describing the possible
3462  * setup methods which can be used with this configuration.
3463  */
3464  int methods;
3465  /**
3466  * The device type associated with the configuration.
3467  *
3468  * Must be set for AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX and
3469  * AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX, otherwise unused.
3470  */
3472 } AVCodecHWConfig;
3473 
3474 typedef struct AVCodecDefault AVCodecDefault;
3475 
3476 struct AVSubtitle;
3477 
3478 /**
3479  * AVCodec.
3480  */
3481 typedef struct AVCodec {
3482  /**
3483  * Name of the codec implementation.
3484  * The name is globally unique among encoders and among decoders (but an
3485  * encoder and a decoder can share the same name).
3486  * This is the primary way to find a codec from the user perspective.
3487  */
3488  const char *name;
3489  /**
3490  * Descriptive name for the codec, meant to be more human readable than name.
3491  * You should use the NULL_IF_CONFIG_SMALL() macro to define it.
3492  */
3493  const char *long_name;
3496  /**
3497  * Codec capabilities.
3498  * see AV_CODEC_CAP_*
3499  */
3501  const AVRational *supported_framerates; ///< array of supported framerates, or NULL if any, array is terminated by {0,0}
3502  const enum AVPixelFormat *pix_fmts; ///< array of supported pixel formats, or NULL if unknown, array is terminated by -1
3503  const int *supported_samplerates; ///< array of supported audio samplerates, or NULL if unknown, array is terminated by 0
3504  const enum AVSampleFormat *sample_fmts; ///< array of supported sample formats, or NULL if unknown, array is terminated by -1
3505  const uint64_t *channel_layouts; ///< array of support channel layouts, or NULL if unknown. array is terminated by 0
3506  uint8_t max_lowres; ///< maximum value for lowres supported by the decoder
3507  const AVClass *priv_class; ///< AVClass for the private context
3508  const AVProfile *profiles; ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
3509 
3510  /**
3511  * Group name of the codec implementation.
3512  * This is a short symbolic name of the wrapper backing this codec. A
3513  * wrapper uses some kind of external implementation for the codec, such
3514  * as an external library, or a codec implementation provided by the OS or
3515  * the hardware.
3516  * If this field is NULL, this is a builtin, libavcodec native codec.
3517  * If non-NULL, this will be the suffix in AVCodec.name in most cases
3518  * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
3519  */
3520  const char *wrapper_name;
3521 
3522  /*****************************************************************
3523  * No fields below this line are part of the public API. They
3524  * may not be used outside of libavcodec and can be changed and
3525  * removed at will.
3526  * New public fields should be added right above.
3527  *****************************************************************
3528  */
3530  struct AVCodec *next;
3531  /**
3532  * @name Frame-level threading support functions
3533  * @{
3534  */
3535  /**
3536  * If defined, called on thread contexts when they are created.
3537  * If the codec allocates writable tables in init(), re-allocate them here.
3538  * priv_data will be set to a copy of the original.
3539  */
3541  /**
3542  * Copy necessary context variables from a previous thread context to the current one.
3543  * If not defined, the next thread will start automatically; otherwise, the codec
3544  * must call ff_thread_finish_setup().
3545  *
3546  * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
3547  */
3549  /** @} */
3550 
3551  /**
3552  * Private codec-specific defaults.
3553  */
3555 
3556  /**
3557  * Initialize codec static data, called from avcodec_register().
3558  *
3559  * This is not intended for time consuming operations as it is
3560  * run for every codec regardless of that codec being used.
3561  */
3562  void (*init_static_data)(struct AVCodec *codec);
3563 
3565  int (*encode_sub)(AVCodecContext *, uint8_t *buf, int buf_size,
3566  const struct AVSubtitle *sub);
3567  /**
3568  * Encode data to an AVPacket.
3569  *
3570  * @param avctx codec context
3571  * @param avpkt output AVPacket (may contain a user-provided buffer)
3572  * @param[in] frame AVFrame containing the raw data to be encoded
3573  * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
3574  * non-empty packet was returned in avpkt.
3575  * @return 0 on success, negative error code on failure
3576  */
3577  int (*encode2)(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame,
3578  int *got_packet_ptr);
3579  int (*decode)(AVCodecContext *, void *outdata, int *outdata_size, AVPacket *avpkt);
3580  int (*close)(AVCodecContext *);
3581  /**
3582  * Encode API with decoupled packet/frame dataflow. The API is the
3583  * same as the avcodec_ prefixed APIs (avcodec_send_frame() etc.), except
3584  * that:
3585  * - never called if the codec is closed or the wrong type,
3586  * - if AV_CODEC_CAP_DELAY is not set, drain frames are never sent,
3587  * - only one drain frame is ever passed down,
3588  */
3589  int (*send_frame)(AVCodecContext *avctx, const AVFrame *frame);
3590  int (*receive_packet)(AVCodecContext *avctx, AVPacket *avpkt);
3591 
3592  /**
3593  * Decode API with decoupled packet/frame dataflow. This function is called
3594  * to get one output frame. It should call ff_decode_get_packet() to obtain
3595  * input data.
3596  */
3598  /**
3599  * Flush buffers.
3600  * Will be called when seeking
3601  */
3603  /**
3604  * Internal codec capabilities.
3605  * See FF_CODEC_CAP_* in internal.h
3606  */
3608 
3609  /**
3610  * Decoding only, a comma-separated list of bitstream filters to apply to
3611  * packets before decoding.
3612  */
3613  const char *bsfs;
3614 
3615  /**
3616  * Array of pointers to hardware configurations supported by the codec,
3617  * or NULL if no hardware supported. The array is terminated by a NULL
3618  * pointer.
3619  *
3620  * The user can only access this field via avcodec_get_hw_config().
3621  */
3623 } AVCodec;
3624 
3625 #if FF_API_CODEC_GET_SET
3627 int av_codec_get_max_lowres(const AVCodec *codec);
3628 #endif
3629 
3630 struct MpegEncContext;
3631 
3632 /**
3633  * Retrieve supported hardware configurations for a codec.
3634  *
3635  * Values of index from zero to some maximum return the indexed configuration
3636  * descriptor; all other values return NULL. If the codec does not support
3637  * any hardware configurations then it will always return NULL.
3638  */
3639 const AVCodecHWConfig *avcodec_get_hw_config(const AVCodec *codec, int index);
3640 
3641 /**
3642  * @defgroup lavc_hwaccel AVHWAccel
3643  *
3644  * @note Nothing in this structure should be accessed by the user. At some
3645  * point in future it will not be externally visible at all.
3646  *
3647  * @{
3648  */
3649 typedef struct AVHWAccel {
3650  /**
3651  * Name of the hardware accelerated codec.
3652  * The name is globally unique among encoders and among decoders (but an
3653  * encoder and a decoder can share the same name).
3654  */
3655  const char *name;
3656 
3657  /**
3658  * Type of codec implemented by the hardware accelerator.
3659  *
3660  * See AVMEDIA_TYPE_xxx
3661  */
3663 
3664  /**
3665  * Codec implemented by the hardware accelerator.
3666  *
3667  * See AV_CODEC_ID_xxx
3668  */
3670 
3671  /**
3672  * Supported pixel format.
3673  *
3674  * Only hardware accelerated formats are supported here.
3675  */
3677 
3678  /**
3679  * Hardware accelerated codec capabilities.
3680  * see AV_HWACCEL_CODEC_CAP_*
3681  */
3683 
3684  /*****************************************************************
3685  * No fields below this line are part of the public API. They
3686  * may not be used outside of libavcodec and can be changed and
3687  * removed at will.
3688  * New public fields should be added right above.
3689  *****************************************************************
3690  */
3691 
3692  /**
3693  * Allocate a custom buffer
3694  */
3696 
3697  /**
3698  * Called at the beginning of each frame or field picture.
3699  *
3700  * Meaningful frame information (codec specific) is guaranteed to
3701  * be parsed at this point. This function is mandatory.
3702  *
3703  * Note that buf can be NULL along with buf_size set to 0.
3704  * Otherwise, this means the whole frame is available at this point.
3705  *
3706  * @param avctx the codec context
3707  * @param buf the frame data buffer base
3708  * @param buf_size the size of the frame in bytes
3709  * @return zero if successful, a negative value otherwise
3710  */
3711  int (*start_frame)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3712 
3713  /**
3714  * Callback for parameter data (SPS/PPS/VPS etc).
3715  *
3716  * Useful for hardware decoders which keep persistent state about the
3717  * video parameters, and need to receive any changes to update that state.
3718  *
3719  * @param avctx the codec context
3720  * @param type the nal unit type
3721  * @param buf the nal unit data buffer
3722  * @param buf_size the size of the nal unit in bytes
3723  * @return zero if successful, a negative value otherwise
3724  */
3725  int (*decode_params)(AVCodecContext *avctx, int type, const uint8_t *buf, uint32_t buf_size);
3726 
3727  /**
3728  * Callback for each slice.
3729  *
3730  * Meaningful slice information (codec specific) is guaranteed to
3731  * be parsed at this point. This function is mandatory.
3732  * The only exception is XvMC, that works on MB level.
3733  *
3734  * @param avctx the codec context
3735  * @param buf the slice data buffer base
3736  * @param buf_size the size of the slice in bytes
3737  * @return zero if successful, a negative value otherwise
3738  */
3739  int (*decode_slice)(AVCodecContext *avctx, const uint8_t *buf, uint32_t buf_size);
3740 
3741  /**
3742  * Called at the end of each frame or field picture.
3743  *
3744  * The whole picture is parsed at this point and can now be sent
3745  * to the hardware accelerator. This function is mandatory.
3746  *
3747  * @param avctx the codec context
3748  * @return zero if successful, a negative value otherwise
3749  */
3750  int (*end_frame)(AVCodecContext *avctx);
3751 
3752  /**
3753  * Size of per-frame hardware accelerator private data.
3754  *
3755  * Private data is allocated with av_mallocz() before
3756  * AVCodecContext.get_buffer() and deallocated after
3757  * AVCodecContext.release_buffer().
3758  */
3760 
3761  /**
3762  * Called for every Macroblock in a slice.
3763  *
3764  * XvMC uses it to replace the ff_mpv_reconstruct_mb().
3765  * Instead of decoding to raw picture, MB parameters are
3766  * stored in an array provided by the video driver.
3767  *
3768  * @param s the mpeg context
3769  */
3771 
3772  /**
3773  * Initialize the hwaccel private data.
3774  *
3775  * This will be called from ff_get_format(), after hwaccel and
3776  * hwaccel_context are set and the hwaccel private data in AVCodecInternal
3777  * is allocated.
3778  */
3780 
3781  /**
3782  * Uninitialize the hwaccel private data.
3783  *
3784  * This will be called from get_format() or avcodec_close(), after hwaccel
3785  * and hwaccel_context are already uninitialized.
3786  */
3788 
3789  /**
3790  * Size of the private data to allocate in
3791  * AVCodecInternal.hwaccel_priv_data.
3792  */
3794 
3795  /**
3796  * Internal hwaccel capabilities.
3797  */
3799 
3800  /**
3801  * Fill the given hw_frames context with current codec parameters. Called
3802  * from get_format. Refer to avcodec_get_hw_frames_parameters() for
3803  * details.
3804  *
3805  * This CAN be called before AVHWAccel.init is called, and you must assume
3806  * that avctx->hwaccel_priv_data is invalid.
3807  */
3808  int (*frame_params)(AVCodecContext *avctx, AVBufferRef *hw_frames_ctx);
3809 } AVHWAccel;
3810 
3811 /**
3812  * HWAccel is experimental and is thus avoided in favor of non experimental
3813  * codecs
3814  */
3815 #define AV_HWACCEL_CODEC_CAP_EXPERIMENTAL 0x0200
3816 
3817 /**
3818  * Hardware acceleration should be used for decoding even if the codec level
3819  * used is unknown or higher than the maximum supported level reported by the
3820  * hardware driver.
3821  *
3822  * It's generally a good idea to pass this flag unless you have a specific
3823  * reason not to, as hardware tends to under-report supported levels.
3824  */
3825 #define AV_HWACCEL_FLAG_IGNORE_LEVEL (1 << 0)
3826 
3827 /**
3828  * Hardware acceleration can output YUV pixel formats with a different chroma
3829  * sampling than 4:2:0 and/or other than 8 bits per component.
3830  */
3831 #define AV_HWACCEL_FLAG_ALLOW_HIGH_DEPTH (1 << 1)
3832 
3833 /**
3834  * Hardware acceleration should still be attempted for decoding when the
3835  * codec profile does not match the reported capabilities of the hardware.
3836  *
3837  * For example, this can be used to try to decode baseline profile H.264
3838  * streams in hardware - it will often succeed, because many streams marked
3839  * as baseline profile actually conform to constrained baseline profile.
3840  *
3841  * @warning If the stream is actually not supported then the behaviour is
3842  * undefined, and may include returning entirely incorrect output
3843  * while indicating success.
3844  */
3845 #define AV_HWACCEL_FLAG_ALLOW_PROFILE_MISMATCH (1 << 2)
3846 
3847 /**
3848  * @}
3849  */
3850 
3851 #if FF_API_AVPICTURE
3852 /**
3853  * @defgroup lavc_picture AVPicture
3854  *
3855  * Functions for working with AVPicture
3856  * @{
3857  */
3858 
3859 /**
3860  * Picture data structure.
3861  *
3862  * Up to four components can be stored into it, the last component is
3863  * alpha.
3864  * @deprecated use AVFrame or imgutils functions instead
3865  */
3866 typedef struct AVPicture {
3868  uint8_t *data[AV_NUM_DATA_POINTERS]; ///< pointers to the image data planes
3870  int linesize[AV_NUM_DATA_POINTERS]; ///< number of bytes per line
3871 } AVPicture;
3872 
3873 /**
3874  * @}
3875  */
3876 #endif
3877 
3880 
3881  SUBTITLE_BITMAP, ///< A bitmap, pict will be set
3882 
3883  /**
3884  * Plain text, the text field must be set by the decoder and is
3885  * authoritative. ass and pict fields may contain approximations.
3886  */
3888 
3889  /**
3890  * Formatted text, the ass field must be set by the decoder and is
3891  * authoritative. pict and text fields may contain approximations.
3892  */
3894 };
3895 
3896 #define AV_SUBTITLE_FLAG_FORCED 0x00000001
3897 
3898 typedef struct AVSubtitleRect {
3899  int x; ///< top left corner of pict, undefined when pict is not set
3900  int y; ///< top left corner of pict, undefined when pict is not set
3901  int w; ///< width of pict, undefined when pict is not set
3902  int h; ///< height of pict, undefined when pict is not set
3903  int nb_colors; ///< number of colors in pict, undefined when pict is not set
3904 
3905 #if FF_API_AVPICTURE
3906  /**
3907  * @deprecated unused
3908  */
3911 #endif
3912  /**
3913  * data+linesize for the bitmap of this subtitle.
3914  * Can be set for text/ass as well once they are rendered.
3915  */
3917  int linesize[4];
3918 
3920 
3921  char *text; ///< 0 terminated plain UTF-8 text
3922 
3923  /**
3924  * 0 terminated ASS/SSA compatible event line.
3925  * The presentation of this is unaffected by the other values in this
3926  * struct.
3927  */
3928  char *ass;
3929 
3930  int flags;
3931 } AVSubtitleRect;
3932 
3933 typedef struct AVSubtitle {
3934  uint16_t format; /* 0 = graphics */
3935  uint32_t start_display_time; /* relative to packet pts, in ms */
3936  uint32_t end_display_time; /* relative to packet pts, in ms */
3937  unsigned num_rects;
3939  int64_t pts; ///< Same as packet pts, in AV_TIME_BASE
3940 } AVSubtitle;
3941 
3942 /**
3943  * This struct describes the properties of an encoded stream.
3944  *
3945  * sizeof(AVCodecParameters) is not a part of the public ABI, this struct must
3946  * be allocated with avcodec_parameters_alloc() and freed with
3947  * avcodec_parameters_free().
3948  */
3949 typedef struct AVCodecParameters {
3950  /**
3951  * General type of the encoded data.
3952  */
3954  /**
3955  * Specific type of the encoded data (the codec used).
3956  */
3958  /**
3959  * Additional information about the codec (corresponds to the AVI FOURCC).
3960  */
3961  uint32_t codec_tag;
3962 
3963  /**
3964  * Extra binary data needed for initializing the decoder, codec-dependent.
3965  *
3966  * Must be allocated with av_malloc() and will be freed by
3967  * avcodec_parameters_free(). The allocated size of extradata must be at
3968  * least extradata_size + AV_INPUT_BUFFER_PADDING_SIZE, with the padding
3969  * bytes zeroed.
3970  */
3972  /**
3973  * Size of the extradata content in bytes.
3974  */
3976 
3977  /**
3978  * - video: the pixel format, the value corresponds to enum AVPixelFormat.
3979  * - audio: the sample format, the value corresponds to enum AVSampleFormat.
3980  */
3981  int format;
3982 
3983  /**
3984  * The average bitrate of the encoded data (in bits per second).
3985  */
3986  int64_t bit_rate;
3987 
3988  /**
3989  * The number of bits per sample in the codedwords.
3990  *
3991  * This is basically the bitrate per sample. It is mandatory for a bunch of
3992  * formats to actually decode them. It's the number of bits for one sample in
3993  * the actual coded bitstream.
3994  *
3995  * This could be for example 4 for ADPCM
3996  * For PCM formats this matches bits_per_raw_sample
3997  * Can be 0
3998  */
4000 
4001  /**
4002  * This is the number of valid bits in each output sample. If the
4003  * sample format has more bits, the least significant bits are additional
4004  * padding bits, which are always 0. Use right shifts to reduce the sample
4005  * to its actual size. For example, audio formats with 24 bit samples will
4006  * have bits_per_raw_sample set to 24, and format set to AV_SAMPLE_FMT_S32.
4007  * To get the original sample use "(int32_t)sample >> 8"."
4008  *
4009  * For ADPCM this might be 12 or 16 or similar
4010  * Can be 0
4011  */
4013 
4014  /**
4015  * Codec-specific bitstream restrictions that the stream conforms to.
4016  */
4017  int profile;
4018  int level;
4019 
4020  /**
4021  * Video only. The dimensions of the video frame in pixels.
4022  */
4023  int width;
4024  int height;
4025 
4026  /**
4027  * Video only. The aspect ratio (width / height) which a single pixel
4028  * should have when displayed.
4029  *
4030  * When the aspect ratio is unknown / undefined, the numerator should be
4031  * set to 0 (the denominator may have any value).
4032  */
4034 
4035  /**
4036  * Video only. The order of the fields in interlaced video.
4037  */
4038  enum AVFieldOrder field_order;
4039 
4040  /**
4041  * Video only. Additional colorspace characteristics.
4042  */
4046  enum AVColorSpace color_space;
4047  enum AVChromaLocation chroma_location;
4048 
4049  /**
4050  * Video only. Number of delayed frames.
4051  */
4053 
4054  /**
4055  * Audio only. The channel layout bitmask. May be 0 if the channel layout is
4056  * unknown or unspecified, otherwise the number of bits set must be equal to
4057  * the channels field.
4058  */
4059  uint64_t channel_layout;
4060  /**
4061  * Audio only. The number of audio channels.
4062  */
4064  /**
4065  * Audio only. The number of audio samples per second.
4066  */
4068  /**
4069  * Audio only. The number of bytes per coded audio frame, required by some
4070  * formats.
4071  *
4072  * Corresponds to nBlockAlign in WAVEFORMATEX.
4073  */
4075  /**
4076  * Audio only. Audio frame size, if known. Required by some formats to be static.
4077  */
4079 
4080  /**
4081  * Audio only. The amount of padding (in samples) inserted by the encoder at
4082  * the beginning of the audio. I.e. this number of leading decoded samples
4083  * must be discarded by the caller to get the original audio without leading
4084  * padding.
4085  */
4087  /**
4088  * Audio only. The amount of padding (in samples) appended by the encoder to
4089  * the end of the audio. I.e. this number of decoded samples must be
4090  * discarded by the caller from the end of the stream to get the original
4091  * audio without any trailing padding.
4092  */
4094  /**
4095  * Audio only. Number of samples to skip after a discontinuity.
4096  */
4099 
4100 /**
4101  * Iterate over all registered codecs.
4102  *
4103  * @param opaque a pointer where libavcodec will store the iteration state. Must
4104  * point to NULL to start the iteration.
4105  *
4106  * @return the next registered codec or NULL when the iteration is
4107  * finished
4108  */
4109 const AVCodec *av_codec_iterate(void **opaque);
4110 
4111 #if FF_API_NEXT
4112 /**
4113  * If c is NULL, returns the first registered codec,
4114  * if c is non-NULL, returns the next registered codec after c,
4115  * or NULL if c is the last one.
4116  */
4118 AVCodec *av_codec_next(const AVCodec *c);
4119 #endif
4120 
4121 /**
4122  * Return the LIBAVCODEC_VERSION_INT constant.
4123  */
4124 unsigned avcodec_version(void);
4125 
4126 /**
4127  * Return the libavcodec build-time configuration.
4128  */
4129 const char *avcodec_configuration(void);
4130 
4131 /**
4132  * Return the libavcodec license.
4133  */
4134 const char *avcodec_license(void);
4135 
4136 #if FF_API_NEXT
4137 /**
4138  * Register the codec codec and initialize libavcodec.
4139  *
4140  * @warning either this function or avcodec_register_all() must be called
4141  * before any other libavcodec functions.
4142  *
4143  * @see avcodec_register_all()
4144  */
4146 void avcodec_register(AVCodec *codec);
4147 
4148 /**
4149  * Register all the codecs, parsers and bitstream filters which were enabled at
4150  * configuration time. If you do not call this function you can select exactly
4151  * which formats you want to support, by using the individual registration
4152  * functions.
4153  *
4154  * @see avcodec_register
4155  * @see av_register_codec_parser
4156  * @see av_register_bitstream_filter
4157  */
4159 void avcodec_register_all(void);
4160 #endif
4161 
4162 /**
4163  * Allocate an AVCodecContext and set its fields to default values. The
4164  * resulting struct should be freed with avcodec_free_context().
4165  *
4166  * @param codec if non-NULL, allocate private data and initialize defaults
4167  * for the given codec. It is illegal to then call avcodec_open2()
4168  * with a different codec.
4169  * If NULL, then the codec-specific defaults won't be initialized,
4170  * which may result in suboptimal default settings (this is
4171  * important mainly for encoders, e.g. libx264).
4172  *
4173  * @return An AVCodecContext filled with default values or NULL on failure.
4174  */
4176 
4177 /**
4178  * Free the codec context and everything associated with it and write NULL to
4179  * the provided pointer.
4180  */
4181 void avcodec_free_context(AVCodecContext **avctx);
4182 
4183 #if FF_API_GET_CONTEXT_DEFAULTS
4184 /**
4185  * @deprecated This function should not be used, as closing and opening a codec
4186  * context multiple time is not supported. A new codec context should be
4187  * allocated for each new use.
4188  */
4190 #endif
4191 
4192 /**
4193  * Get the AVClass for AVCodecContext. It can be used in combination with
4194  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4195  *
4196  * @see av_opt_find().
4197  */
4198 const AVClass *avcodec_get_class(void);
4199 
4200 #if FF_API_COPY_CONTEXT
4201 /**
4202  * Get the AVClass for AVFrame. It can be used in combination with
4203  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4204  *
4205  * @see av_opt_find().
4206  */
4207 const AVClass *avcodec_get_frame_class(void);
4208 
4209 /**
4210  * Get the AVClass for AVSubtitleRect. It can be used in combination with
4211  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
4212  *
4213  * @see av_opt_find().
4214  */
4216 
4217 /**
4218  * Copy the settings of the source AVCodecContext into the destination
4219  * AVCodecContext. The resulting destination codec context will be
4220  * unopened, i.e. you are required to call avcodec_open2() before you
4221  * can use this AVCodecContext to decode/encode video/audio data.
4222  *
4223  * @param dest target codec context, should be initialized with
4224  * avcodec_alloc_context3(NULL), but otherwise uninitialized
4225  * @param src source codec context
4226  * @return AVERROR() on error (e.g. memory allocation error), 0 on success
4227  *
4228  * @deprecated The semantics of this function are ill-defined and it should not
4229  * be used. If you need to transfer the stream parameters from one codec context
4230  * to another, use an intermediate AVCodecParameters instance and the
4231  * avcodec_parameters_from_context() / avcodec_parameters_to_context()
4232  * functions.
4233  */
4236 #endif
4237 
4238 /**
4239  * Allocate a new AVCodecParameters and set its fields to default values
4240  * (unknown/invalid/0). The returned struct must be freed with
4241  * avcodec_parameters_free().
4242  */
4244 
4245 /**
4246  * Free an AVCodecParameters instance and everything associated with it and
4247  * write NULL to the supplied pointer.
4248  */
4250 
4251 /**
4252  * Copy the contents of src to dst. Any allocated fields in dst are freed and
4253  * replaced with newly allocated duplicates of the corresponding fields in src.
4254  *
4255  * @return >= 0 on success, a negative AVERROR code on failure.
4256  */
4258 
4259 /**
4260  * Fill the parameters struct based on the values from the supplied codec
4261  * context. Any allocated fields in par are freed and replaced with duplicates
4262  * of the corresponding fields in codec.
4263  *
4264  * @return >= 0 on success, a negative AVERROR code on failure
4265  */
4267  const AVCodecContext *codec);
4268 
4269 /**
4270  * Fill the codec context based on the values from the supplied codec
4271  * parameters. Any allocated fields in codec that have a corresponding field in
4272  * par are freed and replaced with duplicates of the corresponding field in par.
4273  * Fields in codec that do not have a counterpart in par are not touched.
4274  *
4275  * @return >= 0 on success, a negative AVERROR code on failure.
4276  */
4278  const AVCodecParameters *par);
4279 
4280 /**
4281  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
4282  * function the context has to be allocated with avcodec_alloc_context3().
4283  *
4284  * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
4285  * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
4286  * retrieving a codec.
4287  *
4288  * @warning This function is not thread safe!
4289  *
4290  * @note Always call this function before using decoding routines (such as
4291  * @ref avcodec_receive_frame()).
4292  *
4293  * @code
4294  * avcodec_register_all();
4295  * av_dict_set(&opts, "b", "2.5M", 0);
4296  * codec = avcodec_find_decoder(AV_CODEC_ID_H264);
4297  * if (!codec)
4298  * exit(1);
4299  *
4300  * context = avcodec_alloc_context3(codec);
4301  *
4302  * if (avcodec_open2(context, codec, opts) < 0)
4303  * exit(1);
4304  * @endcode
4305  *
4306  * @param avctx The context to initialize.
4307  * @param codec The codec to open this context for. If a non-NULL codec has been
4308  * previously passed to avcodec_alloc_context3() or
4309  * for this context, then this parameter MUST be either NULL or
4310  * equal to the previously passed codec.
4311  * @param options A dictionary filled with AVCodecContext and codec-private options.
4312  * On return this object will be filled with options that were not found.
4313  *
4314  * @return zero on success, a negative value on error
4315  * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
4316  * av_dict_set(), av_opt_find().
4317  */
4318 int avcodec_open2(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options);
4319 
4320 /**
4321  * Close a given AVCodecContext and free all the data associated with it
4322  * (but not the AVCodecContext itself).
4323  *
4324  * Calling this function on an AVCodecContext that hasn't been opened will free
4325  * the codec-specific data allocated in avcodec_alloc_context3() with a non-NULL
4326  * codec. Subsequent calls will do nothing.
4327  *
4328  * @note Do not use this function. Use avcodec_free_context() to destroy a
4329  * codec context (either open or closed). Opening and closing a codec context
4330  * multiple times is not supported anymore -- use multiple codec contexts
4331  * instead.
4332  */
4333 int avcodec_close(AVCodecContext *avctx);
4334 
4335 /**
4336  * Free all allocated data in the given subtitle struct.
4337  *
4338  * @param sub AVSubtitle to free.
4339  */
4340 void avsubtitle_free(AVSubtitle *sub);
4341 
4342 /**
4343  * @}
4344  */
4345 
4346 /**
4347  * @addtogroup lavc_packet
4348  * @{
4349  */
4350 
4351 /**
4352  * Allocate an AVPacket and set its fields to default values. The resulting
4353  * struct must be freed using av_packet_free().
4354  *
4355  * @return An AVPacket filled with default values or NULL on failure.
4356  *
4357  * @note this only allocates the AVPacket itself, not the data buffers. Those
4358  * must be allocated through other means such as av_new_packet.
4359  *
4360  * @see av_new_packet
4361  */
4362 AVPacket *av_packet_alloc(void);
4363 
4364 /**
4365  * Create a new packet that references the same data as src.
4366  *
4367  * This is a shortcut for av_packet_alloc()+av_packet_ref().
4368  *
4369  * @return newly created AVPacket on success, NULL on error.
4370  *
4371  * @see av_packet_alloc
4372  * @see av_packet_ref
4373  */
4375 
4376 /**
4377  * Free the packet, if the packet is reference counted, it will be
4378  * unreferenced first.
4379  *
4380  * @param pkt packet to be freed. The pointer will be set to NULL.
4381  * @note passing NULL is a no-op.
4382  */
4383 void av_packet_free(AVPacket **pkt);
4384 
4385 /**
4386  * Initialize optional fields of a packet with default values.
4387  *
4388  * Note, this does not touch the data and size members, which have to be
4389  * initialized separately.
4390  *
4391  * @param pkt packet
4392  */
4393 void av_init_packet(AVPacket *pkt);
4394 
4395 /**
4396  * Allocate the payload of a packet and initialize its fields with
4397  * default values.
4398  *
4399  * @param pkt packet
4400  * @param size wanted payload size
4401  * @return 0 if OK, AVERROR_xxx otherwise
4402  */
4403 int av_new_packet(AVPacket *pkt, int size);
4404 
4405 /**
4406  * Reduce packet size, correctly zeroing padding
4407  *
4408  * @param pkt packet
4409  * @param size new size
4410  */
4411 void av_shrink_packet(AVPacket *pkt, int size);
4412 
4413 /**
4414  * Increase packet size, correctly zeroing padding
4415  *
4416  * @param pkt packet
4417  * @param grow_by number of bytes by which to increase the size of the packet
4418  */
4419 int av_grow_packet(AVPacket *pkt, int grow_by);
4420 
4421 /**
4422  * Initialize a reference-counted packet from av_malloc()ed data.
4423  *
4424  * @param pkt packet to be initialized. This function will set the data, size,
4425  * and buf fields, all others are left untouched.
4426  * @param data Data allocated by av_malloc() to be used as packet data. If this
4427  * function returns successfully, the data is owned by the underlying AVBuffer.
4428  * The caller may not access the data through other means.
4429  * @param size size of data in bytes, without the padding. I.e. the full buffer
4430  * size is assumed to be size + AV_INPUT_BUFFER_PADDING_SIZE.
4431  *
4432  * @return 0 on success, a negative AVERROR on error
4433  */
4435 
4436 #if FF_API_AVPACKET_OLD_API
4437 /**
4438  * @warning This is a hack - the packet memory allocation stuff is broken. The
4439  * packet is allocated if it was not really allocated.
4440  *
4441  * @deprecated Use av_packet_ref or av_packet_make_refcounted
4442  */
4444 int av_dup_packet(AVPacket *pkt);
4445 /**
4446  * Copy packet, including contents
4447  *
4448  * @return 0 on success, negative AVERROR on fail
4449  *
4450  * @deprecated Use av_packet_ref
4451  */
4453 int av_copy_packet(AVPacket *dst, const AVPacket *src);
4454 
4455 /**
4456  * Copy packet side data
4457  *
4458  * @return 0 on success, negative AVERROR on fail
4459  *
4460  * @deprecated Use av_packet_copy_props
4461  */
4463 int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
4464 
4465 /**
4466  * Free a packet.
4467  *
4468  * @deprecated Use av_packet_unref
4469  *
4470  * @param pkt packet to free
4471  */
4473 void av_free_packet(AVPacket *pkt);
4474 #endif
4475 /**
4476  * Allocate new information of a packet.
4477  *
4478  * @param pkt packet
4479  * @param type side information type
4480  * @param size side information size
4481  * @return pointer to fresh allocated data or NULL otherwise
4482  */
4484  int size);
4485 
4486 /**
4487  * Wrap an existing array as a packet side data.
4488  *
4489  * @param pkt packet
4490  * @param type side information type
4491  * @param data the side data array. It must be allocated with the av_malloc()
4492  * family of functions. The ownership of the data is transferred to
4493  * pkt.
4494  * @param size side information size
4495  * @return a non-negative number on success, a negative AVERROR code on
4496  * failure. On failure, the packet is unchanged and the data remains
4497  * owned by the caller.
4498  */
4500  uint8_t *data, size_t size);
4501 
4502 /**
4503  * Shrink the already allocated side data buffer
4504  *
4505  * @param pkt packet
4506  * @param type side information type
4507  * @param size new side information size
4508  * @return 0 on success, < 0 on failure
4509  */
4511  int size);
4512 
4513 /**
4514  * Get side information from packet.
4515  *
4516  * @param pkt packet
4517  * @param type desired side information type
4518  * @param size pointer for side information size to store (optional)
4519  * @return pointer to data if present or NULL otherwise
4520  */
4522  int *size);
4523 
4524 #if FF_API_MERGE_SD_API
4527 
4530 #endif
4531 
4533 
4534 /**
4535  * Pack a dictionary for use in side_data.
4536  *
4537  * @param dict The dictionary to pack.
4538  * @param size pointer to store the size of the returned data
4539  * @return pointer to data if successful, NULL otherwise
4540  */
4542 /**
4543  * Unpack a dictionary from side_data.
4544  *
4545  * @param data data from side_data
4546  * @param size size of the data
4547  * @param dict the metadata storage dictionary
4548  * @return 0 on success, < 0 on failure
4549  */
4550 int av_packet_unpack_dictionary(const uint8_t *data, int size, AVDictionary **dict);
4551 
4552 
4553 /**
4554  * Convenience function to free all the side data stored.
4555  * All the other fields stay untouched.
4556  *
4557  * @param pkt packet
4558  */
4560 
4561 /**
4562  * Setup a new reference to the data described by a given packet
4563  *
4564  * If src is reference-counted, setup dst as a new reference to the
4565  * buffer in src. Otherwise allocate a new buffer in dst and copy the
4566  * data from src into it.
4567  *
4568  * All the other fields are copied from src.
4569  *
4570  * @see av_packet_unref
4571  *
4572  * @param dst Destination packet
4573  * @param src Source packet
4574  *
4575  * @return 0 on success, a negative AVERROR on error.
4576  */
4577 int av_packet_ref(AVPacket *dst, const AVPacket *src);
4578 
4579 /**
4580  * Wipe the packet.
4581  *
4582  * Unreference the buffer referenced by the packet and reset the
4583  * remaining packet fields to their default values.
4584  *
4585  * @param pkt The packet to be unreferenced.
4586  */
4588 
4589 /**
4590  * Move every field in src to dst and reset src.
4591  *
4592  * @see av_packet_unref
4593  *
4594  * @param src Source packet, will be reset
4595  * @param dst Destination packet
4596  */
4598 
4599 /**
4600  * Copy only "properties" fields from src to dst.
4601  *
4602  * Properties for the purpose of this function are all the fields
4603  * beside those related to the packet data (buf, data, size)
4604  *
4605  * @param dst Destination packet
4606  * @param src Source packet
4607  *
4608  * @return 0 on success AVERROR on failure.
4609  */
4610 int av_packet_copy_props(AVPacket *dst, const AVPacket *src);
4611 
4612 /**
4613  * Ensure the data described by a given packet is reference counted.
4614  *
4615  * @note This function does not ensure that the reference will be writable.
4616  * Use av_packet_make_writable instead for that purpose.
4617  *
4618  * @see av_packet_ref
4619  * @see av_packet_make_writable
4620  *
4621  * @param pkt packet whose data should be made reference counted.
4622  *
4623  * @return 0 on success, a negative AVERROR on error. On failure, the
4624  * packet is unchanged.
4625  */
4627 
4628 /**
4629  * Create a writable reference for the data described by a given packet,
4630  * avoiding data copy if possible.
4631  *
4632  * @param pkt Packet whose data should be made writable.
4633  *
4634  * @return 0 on success, a negative AVERROR on failure. On failure, the
4635  * packet is unchanged.
4636  */
4638 
4639 /**
4640  * Convert valid timing fields (timestamps / durations) in a packet from one
4641  * timebase to another. Timestamps with unknown values (AV_NOPTS_VALUE) will be
4642  * ignored.
4643  *
4644  * @param pkt packet on which the conversion will be performed
4645  * @param tb_src source timebase, in which the timing fields in pkt are
4646  * expressed
4647  * @param tb_dst destination timebase, to which the timing fields will be
4648  * converted
4649  */
4650 void av_packet_rescale_ts(AVPacket *pkt, AVRational tb_src, AVRational tb_dst);
4651 
4652 /**
4653  * @}
4654  */
4655 
4656 /**
4657  * @addtogroup lavc_decoding
4658  * @{
4659  */
4660 
4661 /**
4662  * Find a registered decoder with a matching codec ID.
4663  *
4664  * @param id AVCodecID of the requested decoder
4665  * @return A decoder if one was found, NULL otherwise.
4666  */
4668 
4669 /**
4670  * Find a registered decoder with the specified name.
4671  *
4672  * @param name name of the requested decoder
4673  * @return A decoder if one was found, NULL otherwise.
4674  */
4676 
4677 /**
4678  * The default callback for AVCodecContext.get_buffer2(). It is made public so
4679  * it can be called by custom get_buffer2() implementations for decoders without
4680  * AV_CODEC_CAP_DR1 set.
4681  */
4683 
4684 /**
4685  * Modify width and height values so that they will result in a memory
4686  * buffer that is acceptable for the codec if you do not use any horizontal
4687  * padding.
4688  *
4689  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4690  */
4692 
4693 /**
4694  * Modify width and height values so that they will result in a memory
4695  * buffer that is acceptable for the codec if you also ensure that all
4696  * line sizes are a multiple of the respective linesize_align[i].
4697  *
4698  * May only be used if a codec with AV_CODEC_CAP_DR1 has been opened.
4699  */
4701  int linesize_align[AV_NUM_DATA_POINTERS]);
4702 
4703 /**
4704  * Converts AVChromaLocation to swscale x/y chroma position.
4705  *
4706  * The positions represent the chroma (0,0) position in a coordinates system
4707  * with luma (0,0) representing the origin and luma(1,1) representing 256,256
4708  *
4709  * @param xpos horizontal chroma sample position
4710  * @param ypos vertical chroma sample position
4711  */
4712 int avcodec_enum_to_chroma_pos(int *xpos, int *ypos, enum AVChromaLocation pos);
4713 
4714 /**
4715  * Converts swscale x/y chroma position to AVChromaLocation.
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 enum AVChromaLocation avcodec_chroma_pos_to_enum(int xpos, int ypos);
4724 
4725 /**
4726  * Decode the audio frame of size avpkt->size from avpkt->data into frame.
4727  *
4728  * Some decoders may support multiple frames in a single AVPacket. Such
4729  * decoders would then just decode the first frame and the return value would be
4730  * less than the packet size. In this case, avcodec_decode_audio4 has to be
4731  * called again with an AVPacket containing the remaining data in order to
4732  * decode the second frame, etc... Even if no frames are returned, the packet
4733  * needs to be fed to the decoder with remaining data until it is completely
4734  * consumed or an error occurs.
4735  *
4736  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4737  * and output. This means that for some packets they will not immediately
4738  * produce decoded output and need to be flushed at the end of decoding to get
4739  * all the decoded data. Flushing is done by calling this function with packets
4740  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4741  * returning samples. It is safe to flush even those decoders that are not
4742  * marked with AV_CODEC_CAP_DELAY, then no samples will be returned.
4743  *
4744  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4745  * larger than the actual read bytes because some optimized bitstream
4746  * readers read 32 or 64 bits at once and could read over the end.
4747  *
4748  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4749  * before packets may be fed to the decoder.
4750  *
4751  * @param avctx the codec context
4752  * @param[out] frame The AVFrame in which to store decoded audio samples.
4753  * The decoder will allocate a buffer for the decoded frame by
4754  * calling the AVCodecContext.get_buffer2() callback.
4755  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4756  * reference counted and the returned reference belongs to the
4757  * caller. The caller must release the frame using av_frame_unref()
4758  * when the frame is no longer needed. The caller may safely write
4759  * to the frame if av_frame_is_writable() returns 1.
4760  * When AVCodecContext.refcounted_frames is set to 0, the returned
4761  * reference belongs to the decoder and is valid only until the
4762  * next call to this function or until closing or flushing the
4763  * decoder. The caller may not write to it.
4764  * @param[out] got_frame_ptr Zero if no frame could be decoded, otherwise it is
4765  * non-zero. Note that this field being set to zero
4766  * does not mean that an error has occurred. For
4767  * decoders with AV_CODEC_CAP_DELAY set, no given decode
4768  * call is guaranteed to produce a frame.
4769  * @param[in] avpkt The input AVPacket containing the input buffer.
4770  * At least avpkt->data and avpkt->size should be set. Some
4771  * decoders might also require additional fields to be set.
4772  * @return A negative error code is returned if an error occurred during
4773  * decoding, otherwise the number of bytes consumed from the input
4774  * AVPacket is returned.
4775  *
4776 * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4777  */
4780  int *got_frame_ptr, const AVPacket *avpkt);
4781 
4782 /**
4783  * Decode the video frame of size avpkt->size from avpkt->data into picture.
4784  * Some decoders may support multiple frames in a single AVPacket, such
4785  * decoders would then just decode the first frame.
4786  *
4787  * @warning The input buffer must be AV_INPUT_BUFFER_PADDING_SIZE larger than
4788  * the actual read bytes because some optimized bitstream readers read 32 or 64
4789  * bits at once and could read over the end.
4790  *
4791  * @warning The end of the input buffer buf should be set to 0 to ensure that
4792  * no overreading happens for damaged MPEG streams.
4793  *
4794  * @note Codecs which have the AV_CODEC_CAP_DELAY capability set have a delay
4795  * between input and output, these need to be fed with avpkt->data=NULL,
4796  * avpkt->size=0 at the end to return the remaining frames.
4797  *
4798  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4799  * before packets may be fed to the decoder.
4800  *
4801  * @param avctx the codec context
4802  * @param[out] picture The AVFrame in which the decoded video frame will be stored.
4803  * Use av_frame_alloc() to get an AVFrame. The codec will
4804  * allocate memory for the actual bitmap by calling the
4805  * AVCodecContext.get_buffer2() callback.
4806  * When AVCodecContext.refcounted_frames is set to 1, the frame is
4807  * reference counted and the returned reference belongs to the
4808  * caller. The caller must release the frame using av_frame_unref()
4809  * when the frame is no longer needed. The caller may safely write
4810  * to the frame if av_frame_is_writable() returns 1.
4811  * When AVCodecContext.refcounted_frames is set to 0, the returned
4812  * reference belongs to the decoder and is valid only until the
4813  * next call to this function or until closing or flushing the
4814  * decoder. The caller may not write to it.
4815  *
4816  * @param[in] avpkt The input AVPacket containing the input buffer.
4817  * You can create such packet with av_init_packet() and by then setting
4818  * data and size, some decoders might in addition need other fields like
4819  * flags&AV_PKT_FLAG_KEY. All decoders are designed to use the least
4820  * fields possible.
4821  * @param[in,out] got_picture_ptr Zero if no frame could be decompressed, otherwise, it is nonzero.
4822  * @return On error a negative value is returned, otherwise the number of bytes
4823  * used or zero if no frame could be decompressed.
4824  *
4825  * @deprecated Use avcodec_send_packet() and avcodec_receive_frame().
4826  */
4828 int avcodec_decode_video2(AVCodecContext *avctx, AVFrame *picture,
4829  int *got_picture_ptr,
4830  const AVPacket *avpkt);
4831 
4832 /**
4833  * Decode a subtitle message.
4834  * Return a negative value on error, otherwise return the number of bytes used.
4835  * If no subtitle could be decompressed, got_sub_ptr is zero.
4836  * Otherwise, the subtitle is stored in *sub.
4837  * Note that AV_CODEC_CAP_DR1 is not available for subtitle codecs. This is for
4838  * simplicity, because the performance difference is expect to be negligible
4839  * and reusing a get_buffer written for video codecs would probably perform badly
4840  * due to a potentially very different allocation pattern.
4841  *
4842  * Some decoders (those marked with AV_CODEC_CAP_DELAY) have a delay between input
4843  * and output. This means that for some packets they will not immediately
4844  * produce decoded output and need to be flushed at the end of decoding to get
4845  * all the decoded data. Flushing is done by calling this function with packets
4846  * with avpkt->data set to NULL and avpkt->size set to 0 until it stops
4847  * returning subtitles. It is safe to flush even those decoders that are not
4848  * marked with AV_CODEC_CAP_DELAY, then no subtitles will be returned.
4849  *
4850  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4851  * before packets may be fed to the decoder.
4852  *
4853  * @param avctx the codec context
4854  * @param[out] sub The Preallocated AVSubtitle in which the decoded subtitle will be stored,
4855  * must be freed with avsubtitle_free if *got_sub_ptr is set.
4856  * @param[in,out] got_sub_ptr Zero if no subtitle could be decompressed, otherwise, it is nonzero.
4857  * @param[in] avpkt The input AVPacket containing the input buffer.
4858  */
4860  int *got_sub_ptr,
4861  AVPacket *avpkt);
4862 
4863 /**
4864  * Supply raw packet data as input to a decoder.
4865  *
4866  * Internally, this call will copy relevant AVCodecContext fields, which can
4867  * influence decoding per-packet, and apply them when the packet is actually
4868  * decoded. (For example AVCodecContext.skip_frame, which might direct the
4869  * decoder to drop the frame contained by the packet sent with this function.)
4870  *
4871  * @warning The input buffer, avpkt->data must be AV_INPUT_BUFFER_PADDING_SIZE
4872  * larger than the actual read bytes because some optimized bitstream
4873  * readers read 32 or 64 bits at once and could read over the end.
4874  *
4875  * @warning Do not mix this API with the legacy API (like avcodec_decode_video2())
4876  * on the same AVCodecContext. It will return unexpected results now
4877  * or in future libavcodec versions.
4878  *
4879  * @note The AVCodecContext MUST have been opened with @ref avcodec_open2()
4880  * before packets may be fed to the decoder.
4881  *
4882  * @param avctx codec context
4883  * @param[in] avpkt The input AVPacket. Usually, this will be a single video
4884  * frame, or several complete audio frames.
4885  * Ownership of the packet remains with the caller, and the
4886  * decoder will not write to the packet. The decoder may create
4887  * a reference to the packet data (or copy it if the packet is
4888  * not reference-counted).
4889  * Unlike with older APIs, the packet is always fully consumed,
4890  * and if it contains multiple frames (e.g. some audio codecs),
4891  * will require you to call avcodec_receive_frame() multiple
4892  * times afterwards before you can send a new packet.
4893  * It can be NULL (or an AVPacket with data set to NULL and
4894  * size set to 0); in this case, it is considered a flush
4895  * packet, which signals the end of the stream. Sending the
4896  * first flush packet will return success. Subsequent ones are
4897  * unnecessary and will return AVERROR_EOF. If the decoder
4898  * still has frames buffered, it will return them after sending
4899  * a flush packet.
4900  *
4901  * @return 0 on success, otherwise negative error code:
4902  * AVERROR(EAGAIN): input is not accepted in the current state - user
4903  * must read output with avcodec_receive_frame() (once
4904  * all output is read, the packet should be resent, and
4905  * the call will not fail with EAGAIN).
4906  * AVERROR_EOF: the decoder has been flushed, and no new packets can
4907  * be sent to it (also returned if more than 1 flush
4908  * packet is sent)
4909  * AVERROR(EINVAL): codec not opened, it is an encoder, or requires flush
4910  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4911  * other errors: legitimate decoding errors
4912  */
4913 int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);
4914 
4915 /**
4916  * Return decoded output data from a decoder.
4917  *
4918  * @param avctx codec context
4919  * @param frame This will be set to a reference-counted video or audio
4920  * frame (depending on the decoder type) allocated by the
4921  * decoder. Note that the function will always call
4922  * av_frame_unref(frame) before doing anything else.
4923  *
4924  * @return
4925  * 0: success, a frame was returned
4926  * AVERROR(EAGAIN): output is not available in this state - user must try
4927  * to send new input
4928  * AVERROR_EOF: the decoder has been fully flushed, and there will be
4929  * no more output frames
4930  * AVERROR(EINVAL): codec not opened, or it is an encoder
4931  * AVERROR_INPUT_CHANGED: current decoded frame has changed parameters
4932  * with respect to first decoded frame. Applicable
4933  * when flag AV_CODEC_FLAG_DROPCHANGED is set.
4934  * other negative values: legitimate decoding errors
4935  */
4937 
4938 /**
4939  * Supply a raw video or audio frame to the encoder. Use avcodec_receive_packet()
4940  * to retrieve buffered output packets.
4941  *
4942  * @param avctx codec context
4943  * @param[in] frame AVFrame containing the raw audio or video frame to be encoded.
4944  * Ownership of the frame remains with the caller, and the
4945  * encoder will not write to the frame. The encoder may create
4946  * a reference to the frame data (or copy it if the frame is
4947  * not reference-counted).
4948  * It can be NULL, in which case it is considered a flush
4949  * packet. This signals the end of the stream. If the encoder
4950  * still has packets buffered, it will return them after this
4951  * call. Once flushing mode has been entered, additional flush
4952  * packets are ignored, and sending frames will return
4953  * AVERROR_EOF.
4954  *
4955  * For audio:
4956  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
4957  * can have any number of samples.
4958  * If it is not set, frame->nb_samples must be equal to
4959  * avctx->frame_size for all frames except the last.
4960  * The final frame may be smaller than avctx->frame_size.
4961  * @return 0 on success, otherwise negative error code:
4962  * AVERROR(EAGAIN): input is not accepted in the current state - user
4963  * must read output with avcodec_receive_packet() (once
4964  * all output is read, the packet should be resent, and
4965  * the call will not fail with EAGAIN).
4966  * AVERROR_EOF: the encoder has been flushed, and no new frames can
4967  * be sent to it
4968  * AVERROR(EINVAL): codec not opened, refcounted_frames not set, it is a
4969  * decoder, or requires flush
4970  * AVERROR(ENOMEM): failed to add packet to internal queue, or similar
4971  * other errors: legitimate decoding errors
4972  */
4973 int avcodec_send_frame(AVCodecContext *avctx, const AVFrame *frame);
4974 
4975 /**
4976  * Read encoded data from the encoder.
4977  *
4978  * @param avctx codec context
4979  * @param avpkt This will be set to a reference-counted packet allocated by the
4980  * encoder. Note that the function will always call
4981  * av_frame_unref(frame) before doing anything else.
4982  * @return 0 on success, otherwise negative error code:
4983  * AVERROR(EAGAIN): output is not available in the current state - user
4984  * must try to send input
4985  * AVERROR_EOF: the encoder has been fully flushed, and there will be
4986  * no more output packets
4987  * AVERROR(EINVAL): codec not opened, or it is an encoder
4988  * other errors: legitimate decoding errors
4989  */
4990 int avcodec_receive_packet(AVCodecContext *avctx, AVPacket *avpkt);
4991 
4992 /**
4993  * Create and return a AVHWFramesContext with values adequate for hardware
4994  * decoding. This is meant to get called from the get_format callback, and is
4995  * a helper for preparing a AVHWFramesContext for AVCodecContext.hw_frames_ctx.
4996  * This API is for decoding with certain hardware acceleration modes/APIs only.
4997  *
4998  * The returned AVHWFramesContext is not initialized. The caller must do this
4999  * with av_hwframe_ctx_init().
5000  *
5001  * Calling this function is not a requirement, but makes it simpler to avoid
5002  * codec or hardware API specific details when manually allocating frames.
5003  *
5004  * Alternatively to this, an API user can set AVCodecContext.hw_device_ctx,
5005  * which sets up AVCodecContext.hw_frames_ctx fully automatically, and makes
5006  * it unnecessary to call this function or having to care about
5007  * AVHWFramesContext initialization at all.
5008  *
5009  * There are a number of requirements for calling this function:
5010  *
5011  * - It must be called from get_format with the same avctx parameter that was
5012  * passed to get_format. Calling it outside of get_format is not allowed, and
5013  * can trigger undefined behavior.
5014  * - The function is not always supported (see description of return values).
5015  * Even if this function returns successfully, hwaccel initialization could
5016  * fail later. (The degree to which implementations check whether the stream
5017  * is actually supported varies. Some do this check only after the user's
5018  * get_format callback returns.)
5019  * - The hw_pix_fmt must be one of the choices suggested by get_format. If the
5020  * user decides to use a AVHWFramesContext prepared with this API function,
5021  * the user must return the same hw_pix_fmt from get_format.
5022  * - The device_ref passed to this function must support the given hw_pix_fmt.
5023  * - After calling this API function, it is the user's responsibility to
5024  * initialize the AVHWFramesContext (returned by the out_frames_ref parameter),
5025  * and to set AVCodecContext.hw_frames_ctx to it. If done, this must be done
5026  * before returning from get_format (this is implied by the normal
5027  * AVCodecContext.hw_frames_ctx API rules).
5028  * - The AVHWFramesContext parameters may change every time time get_format is
5029  * called. Also, AVCodecContext.hw_frames_ctx is reset before get_format. So
5030  * you are inherently required to go through this process again on every
5031  * get_format call.
5032  * - It is perfectly possible to call this function without actually using
5033  * the resulting AVHWFramesContext. One use-case might be trying to reuse a
5034  * previously initialized AVHWFramesContext, and calling this API function
5035  * only to test whether the required frame parameters have changed.
5036  * - Fields that use dynamically allocated values of any kind must not be set
5037  * by the user unless setting them is explicitly allowed by the documentation.
5038  * If the user sets AVHWFramesContext.free and AVHWFramesContext.user_opaque,
5039  * the new free callback must call the potentially set previous free callback.
5040  * This API call may set any dynamically allocated fields, including the free
5041  * callback.
5042  *
5043  * The function will set at least the following fields on AVHWFramesContext
5044  * (potentially more, depending on hwaccel API):
5045  *
5046  * - All fields set by av_hwframe_ctx_alloc().
5047  * - Set the format field to hw_pix_fmt.
5048  * - Set the sw_format field to the most suited and most versatile format. (An
5049  * implication is that this will prefer generic formats over opaque formats
5050  * with arbitrary restrictions, if possible.)
5051  * - Set the width/height fields to the coded frame size, rounded up to the
5052  * API-specific minimum alignment.
5053  * - Only _if_ the hwaccel requires a pre-allocated pool: set the initial_pool_size
5054  * field to the number of maximum reference surfaces possible with the codec,
5055  * plus 1 surface for the user to work (meaning the user can safely reference
5056  * at most 1 decoded surface at a time), plus additional buffering introduced
5057  * by frame threading. If the hwaccel does not require pre-allocation, the
5058  * field is left to 0, and the decoder will allocate new surfaces on demand
5059  * during decoding.
5060  * - Possibly AVHWFramesContext.hwctx fields, depending on the underlying
5061  * hardware API.
5062  *
5063  * Essentially, out_frames_ref returns the same as av_hwframe_ctx_alloc(), but
5064  * with basic frame parameters set.
5065  *
5066  * The function is stateless, and does not change the AVCodecContext or the
5067  * device_ref AVHWDeviceContext.
5068  *
5069  * @param avctx The context which is currently calling get_format, and which
5070  * implicitly contains all state needed for filling the returned
5071  * AVHWFramesContext properly.
5072  * @param device_ref A reference to the AVHWDeviceContext describing the device
5073  * which will be used by the hardware decoder.
5074  * @param hw_pix_fmt The hwaccel format you are going to return from get_format.
5075  * @param out_frames_ref On success, set to a reference to an _uninitialized_
5076  * AVHWFramesContext, created from the given device_ref.
5077  * Fields will be set to values required for decoding.
5078  * Not changed if an error is returned.
5079  * @return zero on success, a negative value on error. The following error codes
5080  * have special semantics:
5081  * AVERROR(ENOENT): the decoder does not support this functionality. Setup
5082  * is always manual, or it is a decoder which does not
5083  * support setting AVCodecContext.hw_frames_ctx at all,
5084  * or it is a software format.
5085  * AVERROR(EINVAL): it is known that hardware decoding is not supported for
5086  * this configuration, or the device_ref is not supported
5087  * for the hwaccel referenced by hw_pix_fmt.
5088  */
5090  AVBufferRef *device_ref,
5092  AVBufferRef **out_frames_ref);
5093 
5094 
5095 
5096 /**
5097  * @defgroup lavc_parsing Frame parsing
5098  * @{
5099  */
5100 
5103  AV_PICTURE_STRUCTURE_TOP_FIELD, //< coded as top field
5104  AV_PICTURE_STRUCTURE_BOTTOM_FIELD, //< coded as bottom field
5105  AV_PICTURE_STRUCTURE_FRAME, //< coded as frame
5106 };
5107 
5108 typedef struct AVCodecParserContext {
5109  void *priv_data;
5111  int64_t frame_offset; /* offset of the current frame */
5112  int64_t cur_offset; /* current offset
5113  (incremented by each av_parser_parse()) */
5114  int64_t next_frame_offset; /* offset of the next frame */
5115  /* video info */
5116  int pict_type; /* XXX: Put it back in AVCodecContext. */
5117  /**
5118  * This field is used for proper frame duration computation in lavf.
5119  * It signals, how much longer the frame duration of the current frame
5120  * is compared to normal frame duration.
5121  *
5122  * frame_duration = (1 + repeat_pict) * time_base
5123  *
5124  * It is used by codecs like H.264 to display telecined material.
5125  */
5126  int repeat_pict; /* XXX: Put it back in AVCodecContext. */
5127  int64_t pts; /* pts of the current frame */
5128  int64_t dts; /* dts of the current frame */
5129 
5130  /* private data */
5131  int64_t last_pts;
5132  int64_t last_dts;
5134 
5135 #define AV_PARSER_PTS_NB 4
5137  int64_t cur_frame_offset[AV_PARSER_PTS_NB];
5138  int64_t cur_frame_pts[AV_PARSER_PTS_NB];
5139  int64_t cur_frame_dts[AV_PARSER_PTS_NB];
5140 
5141  int flags;
5142 #define PARSER_FLAG_COMPLETE_FRAMES 0x0001
5143 #define PARSER_FLAG_ONCE 0x0002
5144 /// Set if the parser has a valid file offset
5145 #define PARSER_FLAG_FETCHED_OFFSET 0x0004
5146 #define PARSER_FLAG_USE_CODEC_TS 0x1000
5147 
5148  int64_t offset; ///< byte offset from starting packet start
5149  int64_t cur_frame_end[AV_PARSER_PTS_NB];
5150 
5151  /**
5152  * Set by parser to 1 for key frames and 0 for non-key frames.
5153  * It is initialized to -1, so if the parser doesn't set this flag,
5154  * old-style fallback using AV_PICTURE_TYPE_I picture type as key frames
5155  * will be used.
5156  */
5158 
5159 #if FF_API_CONVERGENCE_DURATION
5160  /**
5161  * @deprecated unused
5162  */
5165 #endif
5166 
5167  // Timestamp generation support:
5168  /**
5169  * Synchronization point for start of timestamp generation.
5170  *
5171  * Set to >0 for sync point, 0 for no sync point and <0 for undefined
5172  * (default).
5173  *
5174  * For example, this corresponds to presence of H.264 buffering period
5175  * SEI message.
5176  */
5178 
5179  /**
5180  * Offset of the current timestamp against last timestamp sync point in
5181  * units of AVCodecContext.time_base.
5182  *
5183  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5184  * contain a valid timestamp offset.
5185  *
5186  * Note that the timestamp of sync point has usually a nonzero
5187  * dts_ref_dts_delta, which refers to the previous sync point. Offset of
5188  * the next frame after timestamp sync point will be usually 1.
5189  *
5190  * For example, this corresponds to H.264 cpb_removal_delay.
5191  */
5193 
5194  /**
5195  * Presentation delay of current frame in units of AVCodecContext.time_base.
5196  *
5197  * Set to INT_MIN when dts_sync_point unused. Otherwise, it must
5198  * contain valid non-negative timestamp delta (presentation time of a frame
5199  * must not lie in the past).
5200  *
5201  * This delay represents the difference between decoding and presentation
5202  * time of the frame.
5203  *
5204  * For example, this corresponds to H.264 dpb_output_delay.
5205  */
5207 
5208  /**
5209  * Position of the packet in file.
5210  *
5211  * Analogous to cur_frame_pts/dts
5212  */
5213  int64_t cur_frame_pos[AV_PARSER_PTS_NB];
5214 
5215  /**
5216  * Byte position of currently parsed frame in stream.
5217  */
5218  int64_t pos;
5219 
5220  /**
5221  * Previous frame byte position.
5222  */
5223  int64_t last_pos;
5224 
5225  /**
5226  * Duration of the current frame.
5227  * For audio, this is in units of 1 / AVCodecContext.sample_rate.
5228  * For all other types, this is in units of AVCodecContext.time_base.
5229  */
5231 
5232  enum AVFieldOrder field_order;
5233 
5234  /**
5235  * Indicate whether a picture is coded as a frame, top field or bottom field.
5236  *
5237  * For example, H.264 field_pic_flag equal to 0 corresponds to
5238  * AV_PICTURE_STRUCTURE_FRAME. An H.264 picture with field_pic_flag
5239  * equal to 1 and bottom_field_flag equal to 0 corresponds to
5240  * AV_PICTURE_STRUCTURE_TOP_FIELD.
5241  */
5242  enum AVPictureStructure picture_structure;
5243 
5244  /**
5245  * Picture number incremented in presentation or output order.
5246  * This field may be reinitialized at the first picture of a new sequence.
5247  *
5248  * For example, this corresponds to H.264 PicOrderCnt.
5249  */
5251 
5252  /**
5253  * Dimensions of the decoded video intended for presentation.
5254  */
5255  int width;
5256  int height;
5257 
5258  /**
5259  * Dimensions of the coded video.
5260  */
5263 
5264  /**
5265  * The format of the coded data, corresponds to enum AVPixelFormat for video
5266  * and for enum AVSampleFormat for audio.
5267  *
5268  * Note that a decoder can have considerable freedom in how exactly it
5269  * decodes the data, so the format reported here might be different from the
5270  * one returned by a decoder.
5271  */
5272  int format;
5274 
5275 typedef struct AVCodecParser {
5276  int codec_ids[5]; /* several codec IDs are permitted */
5278  int (*parser_init)(AVCodecParserContext *s);
5279  /* This callback never returns an error, a negative value means that
5280  * the frame start was in a previous packet. */
5281  int (*parser_parse)(AVCodecParserContext *s,
5282  AVCodecContext *avctx,
5283  const uint8_t **poutbuf, int *poutbuf_size,
5284  const uint8_t *buf, int buf_size);
5285  void (*parser_close)(AVCodecParserContext *s);
5286  int (*split)(AVCodecContext *avctx, const uint8_t *buf, int buf_size);
5288 } AVCodecParser;
5289 
5290 /**
5291  * Iterate over all registered codec parsers.
5292  *
5293  * @param opaque a pointer where libavcodec will store the iteration state. Must
5294  * point to NULL to start the iteration.
5295  *
5296  * @return the next registered codec parser or NULL when the iteration is
5297  * finished
5298  */
5299 const AVCodecParser *av_parser_iterate(void **opaque);
5300 
5303 
5307 
5308 /**
5309  * Parse a packet.
5310  *
5311  * @param s parser context.
5312  * @param avctx codec context.
5313  * @param poutbuf set to pointer to parsed buffer or NULL if not yet finished.
5314  * @param poutbuf_size set to size of parsed buffer or zero if not yet finished.
5315  * @param buf input buffer.
5316  * @param buf_size buffer size in bytes without the padding. I.e. the full buffer
5317  size is assumed to be buf_size + AV_INPUT_BUFFER_PADDING_SIZE.
5318  To signal EOF, this should be 0 (so that the last frame
5319  can be output).
5320  * @param pts input presentation timestamp.
5321  * @param dts input decoding timestamp.
5322  * @param pos input byte position in stream.
5323  * @return the number of bytes of the input bitstream used.
5324  *
5325  * Example:
5326  * @code
5327  * while(in_len){
5328  * len = av_parser_parse2(myparser, AVCodecContext, &data, &size,
5329  * in_data, in_len,
5330  * pts, dts, pos);
5331  * in_data += len;
5332  * in_len -= len;
5333  *
5334  * if(size)
5335  * decode_frame(data, size);
5336  * }
5337  * @endcode
5338  */
5340  AVCodecContext *avctx,
5341  uint8_t **poutbuf, int *poutbuf_size,
5342  const uint8_t *buf, int buf_size,
5343  int64_t pts, int64_t dts,
5344  int64_t pos);
5345 
5346 /**
5347  * @return 0 if the output buffer is a subset of the input, 1 if it is allocated and must be freed
5348  * @deprecated use AVBitStreamFilter
5349  */
5351  AVCodecContext *avctx,
5352  uint8_t **poutbuf, int *poutbuf_size,
5353  const uint8_t *buf, int buf_size, int keyframe);
5355 
5356 /**
5357  * @}
5358  * @}
5359  */
5360 
5361 /**
5362  * @addtogroup lavc_encoding
5363  * @{
5364  */
5365 
5366 /**
5367  * Find a registered encoder with a matching codec ID.
5368  *
5369  * @param id AVCodecID of the requested encoder
5370  * @return An encoder if one was found, NULL otherwise.
5371  */
5373 
5374 /**
5375  * Find a registered encoder with the specified name.
5376  *
5377  * @param name name of the requested encoder
5378  * @return An encoder if one was found, NULL otherwise.
5379  */
5381 
5382 /**
5383  * Encode a frame of audio.
5384  *
5385  * Takes input samples from frame and writes the next output packet, if
5386  * available, to avpkt. The output packet does not necessarily contain data for
5387  * the most recent frame, as encoders can delay, split, and combine input frames
5388  * internally as needed.
5389  *
5390  * @param avctx codec context
5391  * @param avpkt output AVPacket.
5392  * The user can supply an output buffer by setting
5393  * avpkt->data and avpkt->size prior to calling the
5394  * function, but if the size of the user-provided data is not
5395  * large enough, encoding will fail. If avpkt->data and
5396  * avpkt->size are set, avpkt->destruct must also be set. All
5397  * other AVPacket fields will be reset by the encoder using
5398  * av_init_packet(). If avpkt->data is NULL, the encoder will
5399  * allocate it. The encoder will set avpkt->size to the size
5400  * of the output packet.
5401  *
5402  * If this function fails or produces no output, avpkt will be
5403  * freed using av_packet_unref().
5404  * @param[in] frame AVFrame containing the raw audio data to be encoded.
5405  * May be NULL when flushing an encoder that has the
5406  * AV_CODEC_CAP_DELAY capability set.
5407  * If AV_CODEC_CAP_VARIABLE_FRAME_SIZE is set, then each frame
5408  * can have any number of samples.
5409  * If it is not set, frame->nb_samples must be equal to
5410  * avctx->frame_size for all frames except the last.
5411  * The final frame may be smaller than avctx->frame_size.
5412  * @param[out] got_packet_ptr This field is set to 1 by libavcodec if the
5413  * output packet is non-empty, and to 0 if it is
5414  * empty. If the function returns an error, the
5415  * packet can be assumed to be invalid, and the
5416  * value of got_packet_ptr is undefined and should
5417  * not be used.
5418  * @return 0 on success, negative error code on failure
5419  *
5420  * @deprecated use avcodec_send_frame()/avcodec_receive_packet() instead
5421  */
5423 int avcodec_encode_audio2(AVCodecContext *avctx, AVPacket *avpkt,
5424  const AVFrame *frame, int *got_packet_ptr);
5425 
5426 /**
5427  * Encode a frame of video.
5428  *
5429  * Takes input raw video data from frame and writes the next output packet, if
5430  * available, to avpkt. The output packet does not necessarily contain data for
5431  * the most recent frame, as encoders can delay and reorder input frames
5432  * internally as needed.
5433  *
5434  * @param avctx codec context
5435  * @param avpkt output AVPacket.
5436  * The user can supply an output buffer by setting
5437  * avpkt->data and avpkt->size prior to calling the
5438  * function, but if the size of the user-provided data is not
5439  * large enough, encoding will fail. All other AVPacket fields
5440  * will be reset by the encoder using av_init_packet(). If
5441  * avpkt->data is NULL, the encoder will allocate it.
5442  * The encoder will set avpkt->size to the size of the
5443  * output packet. The returned data (if any) belongs to the
5444  * caller, he is responsible for freeing it.
54