X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavformat%2Favformat.h;h=143a98639cc3644f9b59e54d2396fc5ced71ca8a;hb=f890677d05bc4e8b494a73373ab4cc19791bf884;hp=9b40eee395e73d221e360596faaf708f4d9ecc42;hpb=27c7ca9c12bb42d5c44d46f24cd970469d0ef55a;p=ffmpeg diff --git a/libavformat/avformat.h b/libavformat/avformat.h index 9b40eee395e..143a98639cc 100644 --- a/libavformat/avformat.h +++ b/libavformat/avformat.h @@ -66,11 +66,23 @@ * set by user for input, always set by user for output (unless you are dealing * with an AVFMT_NOFILE format). * + * @section lavf_options Passing options to (de)muxers + * Lavf allows to configure muxers and demuxers using the @ref avoptions + * mechanism. Generic (format-independent) libavformat options are provided by + * AVFormatContext, they can be examined from a user program by calling + * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass + * from avformat_get_class()). Private (format-specific) options are provided by + * AVFormatContext.priv_data if and only if AVInputFormat.priv_class / + * AVOutputFormat.priv_class of the corresponding format struct is non-NULL. + * Further options may be provided by the @ref AVFormatContext.pb "I/O context", + * if its AVClass is non-NULL, and the protocols layer. See the discussion on + * nesting in @ref avoptions documentation to learn how to access those. + * * @defgroup lavf_decoding Demuxing * @{ * Demuxers read a media file and split it into chunks of data (@em packets). A - * @ref AVPacket "packet" contains one or more frames which belong a single - * elementary stream. In lavf API this process is represented by the + * @ref AVPacket "packet" contains one or more encoded frames which belongs to a + * single elementary stream. In the lavf API this process is represented by the * avformat_open_input() function for opening a file, av_read_frame() for * reading a single packet and finally avformat_close_input(), which does the * cleanup. @@ -100,16 +112,123 @@ * your reading callbacks to it. Then set the @em pb field of your * AVFormatContext to newly created AVIOContext. * + * Since the format of the opened file is in general not known until after + * avformat_open_input() has returned, it is not possible to set demuxer private + * options on a preallocated context. Instead, the options should be passed to + * avformat_open_input() wrapped in an AVDictionary: + * @code + * AVDictionary *options = NULL; + * av_dict_set(&options, "video_size", "640x480", 0); + * av_dict_set(&options, "pixel_format", "rgb24", 0); + * + * if (avformat_open_input(&s, url, NULL, &options) < 0) + * abort(); + * av_dict_free(&options); + * @endcode + * This code passes the private options 'video_size' and 'pixel_format' to the + * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it + * cannot know how to interpret raw video data otherwise. If the format turns + * out to be something different than raw video, those options will not be + * recognized by the demuxer and therefore will not be applied. Such unrecognized + * options are then returned in the options dictionary (recognized options are + * consumed). The calling program can handle such unrecognized options as it + * wishes, e.g. + * @code + * AVDictionaryEntry *e; + * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) { + * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key); + * abort(); + * } + * @endcode + * * After you have finished reading the file, you must close it with * avformat_close_input(). It will free everything associated with the file. * * @section lavf_decoding_read Reading from an opened file + * Reading data from an opened AVFormatContext is done by repeatedly calling + * av_read_frame() on it. Each call, if successful, will return an AVPacket + * containing encoded data for one AVStream, identified by + * AVPacket.stream_index. This packet may be passed straight into the libavcodec + * decoding functions avcodec_decode_video2(), avcodec_decode_audio4() or + * avcodec_decode_subtitle2() if the caller wishes to decode the data. + * + * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be + * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for + * pts/dts, 0 for duration) if the stream does not provide them. The timing + * information will be in AVStream.time_base units, i.e. it has to be + * multiplied by the timebase to convert them to seconds. + * + * If AVPacket.buf is set on the returned packet, then the packet is + * allocated dynamically and the user may keep it indefinitely. + * Otherwise, if AVPacket.buf is NULL, the packet data is backed by a + * static storage somewhere inside the demuxer and the packet is only valid + * until the next av_read_frame() call or closing the file. If the caller + * requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy + * of it. + * In both cases, the packet must be freed with av_free_packet() when it is no + * longer needed. * * @section lavf_decoding_seek Seeking * @} * * @defgroup lavf_encoding Muxing * @{ + * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write + * it into files or other output bytestreams in the specified container format. + * + * The main API functions for muxing are avformat_write_header() for writing the + * file header, av_write_frame() / av_interleaved_write_frame() for writing the + * packets and av_write_trailer() for finalizing the file. + * + * At the beginning of the muxing process, the caller must first call + * avformat_alloc_context() to create a muxing context. The caller then sets up + * the muxer by filling the various fields in this context: + * + * - The @ref AVFormatContext.oformat "oformat" field must be set to select the + * muxer that will be used. + * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb + * "pb" field must be set to an opened IO context, either returned from + * avio_open2() or a custom one. + * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must + * be created with the avformat_new_stream() function. The caller should fill + * the @ref AVStream.codec "stream codec context" information, such as the + * codec @ref AVCodecContext.codec_type "type", @ref AVCodecContext.codec_id + * "id" and other parameters (e.g. width / height, the pixel or sample format, + * etc.) as known. The @ref AVStream.time_base "stream timebase" should + * be set to the timebase that the caller desires to use for this stream (note + * that the timebase actually used by the muxer can be different, as will be + * described later). + * - It is advised to manually initialize only the relevant fields in + * AVCodecContext, rather than using @ref avcodec_copy_context() during + * remuxing: there is no guarantee that the codec context values remain valid + * for both input and output format contexts. + * - The caller may fill in additional information, such as @ref + * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream" + * metadata, @ref AVFormatContext.chapters "chapters", @ref + * AVFormatContext.programs "programs", etc. as described in the + * AVFormatContext documentation. Whether such information will actually be + * stored in the output depends on what the container format and the muxer + * support. + * + * When the muxing context is fully set up, the caller must call + * avformat_write_header() to initialize the muxer internals and write the file + * header. Whether anything actually is written to the IO context at this step + * depends on the muxer, but this function must always be called. Any muxer + * private options must be passed in the options parameter to this function. + * + * The data is then sent to the muxer by repeatedly calling av_write_frame() or + * av_interleaved_write_frame() (consult those functions' documentation for + * discussion on the difference between them; only one of them may be used with + * a single muxing context, they should not be mixed). Do note that the timing + * information on the packets sent to the muxer must be in the corresponding + * AVStream's timebase. That timebase is set by the muxer (in the + * avformat_write_header() step) and may be different from the timebase + * requested by the caller. + * + * Once all the data has been written, the caller must call av_write_trailer() + * to flush any buffered packets and finalize the output file, then close the IO + * context (if any) and finally free the muxing context with + * avformat_free_context(). * @} * * @defgroup lavf_io I/O Read/Write @@ -181,6 +300,11 @@ struct AVFormatContext; * - sorting -- a modified version of a tag that should be used for * sorting will have '-sort' appended. E.g. artist="The Beatles", * artist-sort="Beatles, The". + * - Some protocols and demuxers support metadata updates. After a successful + * call to av_read_packet(), AVFormatContext.event_flags or AVStream.event_flags + * will be updated to indicate if metadata changed. In order to detect metadata + * changes on a stream, you need to loop through all streams in the AVFormatContext + * and check their individual event_flags. * * - Demuxers attempt to export metadata in a generic format, however tags * with no generic equivalents are left as they are stored in the container. @@ -227,6 +351,7 @@ struct AVFormatContext; * Allocate and read the payload of a packet and initialize its * fields with default values. * + * @param s associated IO context * @param pkt packet * @param size desired payload size * @return >0 (read size) if OK, AVERROR_xxx otherwise @@ -242,6 +367,7 @@ int av_get_packet(AVIOContext *s, AVPacket *pkt, int size); * when there is no reasonable way to know (an upper bound of) * the final size. * + * @param s associated IO context * @param pkt packet * @param size amount of data to read * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data @@ -249,6 +375,7 @@ int av_get_packet(AVIOContext *s, AVPacket *pkt, int size); */ int av_append_packet(AVIOContext *s, AVPacket *pkt, int size); +#if FF_API_LAVF_FRAC /*************************************************/ /* fractional numbers for exact pts handling */ @@ -259,6 +386,7 @@ int av_append_packet(AVIOContext *s, AVPacket *pkt, int size); typedef struct AVFrac { int64_t val, num, den; } AVFrac; +#endif /*************************************************/ /* input/output formats */ @@ -272,17 +400,23 @@ typedef struct AVProbeData { const char *filename; unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */ int buf_size; /**< Size of buf except extra allocated bytes */ + const char *mime_type; /**< mime_type, when known. */ } AVProbeData; -#define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection +#define AVPROBE_SCORE_EXTENSION 50 ///< score for file extension +#define AVPROBE_SCORE_MIME 75 ///< score for file mime type +#define AVPROBE_SCORE_MAX 100 ///< maximum score + #define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer /// Demuxer will use avio_open, no opened file should be provided by the caller. #define AVFMT_NOFILE 0x0001 #define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */ #define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */ +#if FF_API_LAVF_FMT_RAWPICTURE #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for - raw picture data. */ + raw picture data. @deprecated Not used anymore */ +#endif #define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */ #define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */ #define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */ @@ -290,10 +424,18 @@ typedef struct AVProbeData { #define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */ #define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */ #define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */ -#define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fallback to binary search via read_timestamp */ -#define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fallback to generic search */ +#define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fall back on binary search via read_timestamp */ +#define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fall back on generic search */ #define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */ #define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */ +#define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly + increasing timestamps, but they must + still be monotonic */ +#define AVFMT_TS_NEGATIVE 0x40000 /**< Format allows muxing negative + timestamps. If not set the timestamp + will be shifted in av_write_frame and + av_interleaved_write_frame so they + start from 0. */ /** * @addtogroup lavf_encoding @@ -310,19 +452,20 @@ typedef struct AVOutputFormat { const char *mime_type; const char *extensions; /**< comma-separated filename extensions */ /* output support */ - enum CodecID audio_codec; /**< default audio codec */ - enum CodecID video_codec; /**< default video codec */ - enum CodecID subtitle_codec; /**< default subtitle codec */ + enum AVCodecID audio_codec; /**< default audio codec */ + enum AVCodecID video_codec; /**< default video codec */ + enum AVCodecID subtitle_codec; /**< default subtitle codec */ /** - * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE, + * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS, - * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH + * AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH, + * AVFMT_TS_NONSTRICT */ int flags; /** * List of supported codec_id-codec_tag pairs, ordered by "better - * choice first". The arrays are all terminated by CODEC_ID_NONE. + * choice first". The arrays are all terminated by AV_CODEC_ID_NONE. */ const struct AVCodecTag * const *codec_tag; @@ -363,7 +506,7 @@ typedef struct AVOutputFormat { * @return 1 if the codec is supported, 0 if it is not. * A negative number if unknown. */ - int (*query_codec)(enum CodecID id, int std_compliance); + int (*query_codec)(enum AVCodecID id, int std_compliance); } AVOutputFormat; /** * @} @@ -405,6 +548,13 @@ typedef struct AVInputFormat { const AVClass *priv_class; ///< AVClass for the private context + /** + * Comma-separated list of mime types. + * It is used check for matching mime types while probing. + * @see av_probe_input_format2 + */ + const char *mime_type; + /***************************************************************** * No fields below this line are part of the public API. They * may not be used outside of libavformat and can be changed and @@ -433,8 +583,8 @@ typedef struct AVInputFormat { /** * Read the format header and initialize the AVFormatContext - * structure. Return 0 if OK. Only used in raw format right - * now. 'avformat_new_stream' should be called to create new streams. + * structure. Return 0 if OK. 'avformat_new_stream' should be + * called to create new streams. */ int (*read_header)(struct AVFormatContext *); @@ -547,30 +697,45 @@ typedef struct AVIndexEntry { */ typedef struct AVStream { int index; /**< stream index in AVFormatContext */ - int id; /**< format-specific stream ID */ - AVCodecContext *codec; /**< codec context */ /** - * Real base framerate of the stream. - * This is the lowest framerate with which all timestamps can be - * represented accurately (it is the least common multiple of all - * framerates in the stream). Note, this value is just a guess! - * For example, if the time base is 1/90000 and all frames have either - * approximately 3600 or 1800 timer ticks, then r_frame_rate will be 50/1. + * Format-specific stream ID. + * decoding: set by libavformat + * encoding: set by the user, replaced by libavformat if left unset + */ + int id; + /** + * Codec context associated with this stream. Allocated and freed by + * libavformat. + * + * - decoding: The demuxer exports codec information stored in the headers + * here. + * - encoding: The user sets codec information, the muxer writes it to the + * output. Mandatory fields as specified in AVCodecContext + * documentation must be set even if this AVCodecContext is + * not actually used for encoding. */ - AVRational r_frame_rate; + AVCodecContext *codec; void *priv_data; +#if FF_API_LAVF_FRAC /** - * encoding: pts generation when outputting stream + * @deprecated this field is unused */ + attribute_deprecated struct AVFrac pts; +#endif /** * This is the fundamental unit of time (in seconds) in terms - * of which frame timestamps are represented. For fixed-fps content, - * time base should be 1/framerate and timestamp increments should be 1. + * of which frame timestamps are represented. + * * decoding: set by libavformat - * encoding: set by libavformat in av_write_header + * encoding: May be set by the caller before avformat_write_header() to + * provide a hint to the muxer about the desired timebase. In + * avformat_write_header(), the muxer will overwrite this field + * with the timebase that will actually be used for the timestamps + * written into the file (which may or may not be related to the + * user-provided one, depending on the format). */ AVRational time_base; @@ -606,6 +771,10 @@ typedef struct AVStream { /** * Average framerate + * + * - demuxing: May be set by libavformat when creating the stream or in + * avformat_find_stream_info(). + * - muxing: May be set by the caller before avformat_write_header(). */ AVRational avg_frame_rate; @@ -618,6 +787,36 @@ typedef struct AVStream { */ AVPacket attached_pic; + /** + * An array of side data that applies to the whole stream (i.e. the + * container does not allow it to change between packets). + * + * There may be no overlap between the side data in this array and side data + * in the packets. I.e. a given side data is either exported by the muxer + * (demuxing) / set by the caller (muxing) in this array, then it never + * appears in the packets, or the side data is exported / sent through + * the packets (always in the first packet where the value becomes known or + * changes), then it does not appear in this array. + * + * - demuxing: Set by libavformat when the stream is created. + * - muxing: May be set by the caller before avformat_write_header(). + * + * Freed by libavformat in avformat_free_context(). + */ + AVPacketSideData *side_data; + /** + * The number of elements in the AVStream.side_data array. + */ + int nb_side_data; + + /** + * Flags for the user to detect events happening on the stream. Flags must + * be cleared by the user once the event has been handled. + * A combination of AVSTREAM_EVENT_FLAG_*. + */ + int event_flags; +#define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata. + /***************************************************************** * All fields below this line are not part of the public API. They * may not be used outside of libavformat and can be changed and @@ -631,25 +830,22 @@ typedef struct AVStream { */ #define MAX_STD_TIMEBASES (60*12+5) struct { - int64_t last_dts; - int64_t duration_gcd; - int duration_count; - double duration_error[MAX_STD_TIMEBASES]; - int64_t codec_info_duration; int nb_decoded_frames; + int found_decoder; + + /** + * Those are used for average framerate estimation. + */ + int64_t fps_first_dts; + int fps_first_dts_idx; + int64_t fps_last_dts; + int fps_last_dts_idx; + } *info; int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */ // Timestamp generation support: - /** - * Timestamp corresponding to the last dts sync point. - * - * Initialized when AVCodecParserContext.dts_sync_point >= 0 and - * a DTS is received from the underlying container. Otherwise set to - * AV_NOPTS_VALUE by default. - */ - int64_t reference_dts; int64_t first_dts; int64_t cur_dts; int64_t last_IP_pts; @@ -711,6 +907,8 @@ typedef struct AVChapter { AVDictionary *metadata; } AVChapter; +typedef struct AVFormatInternal AVFormatInternal; + /** * Format I/O context. * New fields can be added to the end with minor version bumps. @@ -721,32 +919,41 @@ typedef struct AVChapter { */ typedef struct AVFormatContext { /** - * A class for logging and AVOptions. Set by avformat_alloc_context(). + * A class for logging and @ref avoptions. Set by avformat_alloc_context(). * Exports (de)muxer private options if they exist. */ const AVClass *av_class; /** - * Can only be iformat or oformat, not both at the same time. + * The input container format. * - * decoding: set by avformat_open_input(). - * encoding: set by the user. + * Demuxing only, set by avformat_open_input(). */ struct AVInputFormat *iformat; + + /** + * The output container format. + * + * Muxing only, must be set by the caller before avformat_write_header(). + */ struct AVOutputFormat *oformat; /** * Format private data. This is an AVOptions-enabled struct * if and only if iformat/oformat.priv_class is not NULL. + * + * - muxing: set by avformat_write_header() + * - demuxing: set by avformat_open_input() */ void *priv_data; - /* + /** * I/O context. * - * decoding: either set by the user before avformat_open_input() (then - * the user must close it manually) or set by avformat_open_input(). - * encoding: set by the user. + * - demuxing: either set by the user before avformat_open_input() (then + * the user must close it manually) or set by avformat_open_input(). + * - muxing: set by the user before avformat_write_header(). The caller must + * take care of closing / freeing the IO context. * * Do NOT set this field if AVFMT_NOFILE flag is set in * iformat/oformat.flags. In such a case, the (de)muxer will handle @@ -755,39 +962,60 @@ typedef struct AVFormatContext { AVIOContext *pb; /* stream info */ - int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */ + /** + * Flags signalling stream properties. A combination of AVFMTCTX_*. + * Set by libavformat. + */ + int ctx_flags; + /** + * Number of elements in AVFormatContext.streams. + * + * Set by avformat_new_stream(), must not be modified by any other code. + */ + unsigned int nb_streams; /** * A list of all streams in the file. New streams are created with * avformat_new_stream(). * - * decoding: streams are created by libavformat in avformat_open_input(). - * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also - * appear in av_read_frame(). - * encoding: streams are created by the user before avformat_write_header(). + * - demuxing: streams are created by libavformat in avformat_open_input(). + * If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also + * appear in av_read_frame(). + * - muxing: streams are created by the user before avformat_write_header(). + * + * Freed by libavformat in avformat_free_context(). */ - unsigned int nb_streams; AVStream **streams; - char filename[1024]; /**< input or output filename */ + /** + * input or output filename + * + * - demuxing: set by avformat_open_input() + * - muxing: may be set by the caller before avformat_write_header() + */ + char filename[1024]; /** - * Decoding: position of the first frame of the component, in + * Position of the first frame of the component, in * AV_TIME_BASE fractional seconds. NEVER set this value directly: * It is deduced from the AVStream values. + * + * Demuxing only, set by libavformat. */ int64_t start_time; /** - * Decoding: duration of the stream, in AV_TIME_BASE fractional + * Duration of the stream, in AV_TIME_BASE fractional * seconds. Only set this value if you know none of the individual stream * durations and also do not set any of them. This is deduced from the * AVStream values if not set. + * + * Demuxing only, set by libavformat. */ int64_t duration; /** - * Decoding: total stream bitrate in bit/s, 0 if not + * Total stream bitrate in bit/s, 0 if not * available. Never set it directly if the file_size and the * duration are known as Libav can compute it automatically. */ @@ -796,6 +1024,10 @@ typedef struct AVFormatContext { unsigned int packet_size; int max_delay; + /** + * Flags modifying the (de)muxer behaviour. A combination of AVFMT_FLAG_*. + * Set by the user before avformat_open_input() / avformat_write_header(). + */ int flags; #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames. #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index. @@ -803,17 +1035,29 @@ typedef struct AVFormatContext { #define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS #define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container #define AVFMT_FLAG_NOPARSE 0x0020 ///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled +#define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible #define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it. #define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted +#define AVFMT_FLAG_FLUSH_PACKETS 0x0200 ///< Flush the AVIOContext every packet. +/** + * When muxing, try to avoid writing any random/volatile data to the output. + * This includes any random IDs, real-time timestamps/dates, muxer version, etc. + * + * This flag is mainly intended for testing. + */ +#define AVFMT_FLAG_BITEXACT 0x0400 /** - * decoding: size of data to probe; encoding: unused. + * Maximum size of the data read from input for determining + * the input container format. + * Demuxing only, set by the caller before avformat_open_input(). */ unsigned int probesize; /** - * decoding: maximum time (in AV_TIME_BASE units) during which the input should - * be analyzed in avformat_find_stream_info(). + * Maximum duration (in AV_TIME_BASE units) of the data read + * from input in avformat_find_stream_info(). + * Demuxing only, set by the caller before avformat_find_stream_info(). */ int max_analyze_duration; @@ -827,19 +1071,19 @@ typedef struct AVFormatContext { * Forced video codec_id. * Demuxing: Set by user. */ - enum CodecID video_codec_id; + enum AVCodecID video_codec_id; /** * Forced audio codec_id. * Demuxing: Set by user. */ - enum CodecID audio_codec_id; + enum AVCodecID audio_codec_id; /** * Forced subtitle codec_id. * Demuxing: Set by user. */ - enum CodecID subtitle_codec_id; + enum AVCodecID subtitle_codec_id; /** * Maximum amount of memory in bytes to use for the index of each stream. @@ -848,8 +1092,8 @@ typedef struct AVFormatContext { * accurate seeking (depends on demuxer). * Demuxers for which a full in-memory index is mandatory will ignore * this. - * muxing : unused - * demuxing: set by user + * - muxing: unused + * - demuxing: set by user */ unsigned int max_index_size; @@ -859,38 +1103,57 @@ typedef struct AVFormatContext { */ unsigned int max_picture_buffer; + /** + * Number of chapters in AVChapter array. + * When muxing, chapters are normally written in the file header, + * so nb_chapters should normally be initialized before write_header + * is called. Some muxers (e.g. mov and mkv) can also write chapters + * in the trailer. To write chapters in the trailer, nb_chapters + * must be zero when write_header is called and non-zero when + * write_trailer is called. + * - muxing: set by user + * - demuxing: set by libavformat + */ unsigned int nb_chapters; AVChapter **chapters; + /** + * Metadata that applies to the whole file. + * + * - demuxing: set by libavformat in avformat_open_input() + * - muxing: may be set by the caller before avformat_write_header() + * + * Freed by libavformat in avformat_free_context(). + */ AVDictionary *metadata; /** * Start time of the stream in real world time, in microseconds - * since the unix epoch (00:00 1st January 1970). That is, pts=0 - * in the stream was captured at this real world time. - * - encoding: Set by user. - * - decoding: Unused. + * since the Unix epoch (00:00 1st January 1970). That is, pts=0 in the + * stream was captured at this real world time. + * Muxing only, set by the caller before avformat_write_header(). */ int64_t start_time_realtime; /** - * decoding: number of frames used to probe fps + * The number of frames used for determining the framerate in + * avformat_find_stream_info(). + * Demuxing only, set by the caller before avformat_find_stream_info(). */ int fps_probe_size; /** * Error recognition; higher values will detect more errors but may * misdetect some more or less valid parts as errors. - * - encoding: unused - * - decoding: Set by user. + * Demuxing only, set by the caller before avformat_open_input(). */ int error_recognition; /** * Custom interrupt callbacks for the I/O layer. * - * decoding: set by the user before avformat_open_input(). - * encoding: set by the user before avformat_write_header() + * demuxing: set by the user before avformat_open_input(). + * muxing: set by the user before avformat_write_header() * (mainly useful for AVFMT_NOFILE formats). The callback * should also be passed to avio_open2() if it's used to * open the file. @@ -902,43 +1165,62 @@ typedef struct AVFormatContext { */ int debug; #define FF_FDEBUG_TS 0x0001 - /***************************************************************** - * All fields below this line are not part of the public API. They - * may not be used outside of libavformat and can be changed and - * removed at will. - * New public fields should be added right above. - ***************************************************************** + + /** + * Maximum buffering duration for interleaving. + * + * To ensure all the streams are interleaved correctly, + * av_interleaved_write_frame() will wait until it has at least one packet + * for each stream before actually writing any packets to the output file. + * When some streams are "sparse" (i.e. there are large gaps between + * successive packets), this can result in excessive buffering. + * + * This field specifies the maximum difference between the timestamps of the + * first and the last packet in the muxing queue, above which libavformat + * will output a packet regardless of whether it has queued a packet for all + * the streams. + * + * Muxing only, set by the caller before avformat_write_header(). */ + int64_t max_interleave_delta; /** - * This buffer is only needed when packets were already buffered but - * not decoded, for example to get the codec parameters in MPEG - * streams. + * Allow non-standard and experimental extension + * @see AVCodecContext.strict_std_compliance */ - struct AVPacketList *packet_buffer; - struct AVPacketList *packet_buffer_end; + int strict_std_compliance; - /* av_seek_frame() support */ - int64_t data_offset; /**< offset of the first packet */ + /** + * Flags for the user to detect events happening on the file. Flags must + * be cleared by the user once the event has been handled. + * A combination of AVFMT_EVENT_FLAG_*. + */ + int event_flags; +#define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001 ///< The call resulted in updated metadata. /** - * Raw packets from the demuxer, prior to parsing and decoding. - * This buffer is used for buffering packets until the codec can - * be identified, as parsing cannot be done without knowing the - * codec. + * Maximum number of packets to read while waiting for the first timestamp. + * Decoding only. */ - struct AVPacketList *raw_packet_buffer; - struct AVPacketList *raw_packet_buffer_end; + int max_ts_probe; + /** - * Packets split by the parser get queued here. + * Avoid negative timestamps during muxing. + * Any value of the AVFMT_AVOID_NEG_TS_* constants. + * Note, this only works when using av_interleaved_write_frame. + * - muxing: Set by user + * - demuxing: unused */ - struct AVPacketList *parse_queue; - struct AVPacketList *parse_queue_end; + int avoid_negative_ts; +#define AVFMT_AVOID_NEG_TS_AUTO -1 ///< Enabled when required by target format +#define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1 ///< Shift timestamps so they are non negative +#define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2 ///< Shift timestamps so that they start at 0 + /** - * Remaining size available for raw_packet_buffer, in bytes. + * An opaque field for libavformat internal usage. + * Must not be accessed in any way by callers. */ -#define RAW_PACKET_BUFFER_SIZE 2500000 - int raw_packet_buffer_remaining_size; + AVFormatInternal *internal; } AVFormatContext; typedef struct AVPacketList { @@ -1005,14 +1287,14 @@ int avformat_network_deinit(void); * if f is non-NULL, returns the next registered input format after f * or NULL if f is the last one. */ -AVInputFormat *av_iformat_next(AVInputFormat *f); +AVInputFormat *av_iformat_next(const AVInputFormat *f); /** * If f is NULL, returns the first registered output format, * if f is non-NULL, returns the next registered output format after f * or NULL if f is the last one. */ -AVOutputFormat *av_oformat_next(AVOutputFormat *f); +AVOutputFormat *av_oformat_next(const AVOutputFormat *f); /** * Allocate an AVFormatContext. @@ -1044,13 +1326,25 @@ const AVClass *avformat_get_class(void); * * When muxing, should be called by the user before avformat_write_header(). * + * @param s media file handle * @param c If non-NULL, the AVCodecContext corresponding to the new stream * will be initialized to use this codec. This is needed for e.g. codec-specific * defaults to be set, so codec should be provided if it is known. * * @return newly created stream or NULL on error. */ -AVStream *avformat_new_stream(AVFormatContext *s, AVCodec *c); +AVStream *avformat_new_stream(AVFormatContext *s, const AVCodec *c); + +/** + * Get side information from stream. + * + * @param stream stream + * @param type desired side information type + * @param size pointer for side information size to store (optional) + * @return pointer to data if present or NULL otherwise + */ +uint8_t *av_stream_get_side_data(AVStream *stream, + enum AVPacketSideDataType type, int *size); AVProgram *av_new_program(AVFormatContext *s, int id); @@ -1072,6 +1366,7 @@ AVInputFormat *av_find_input_format(const char *short_name); /** * Guess the file format. * + * @param pd data to be probed * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. */ @@ -1080,6 +1375,7 @@ AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened); /** * Guess the file format. * + * @param pd data to be probed * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. * @param score_max A probe score larger that this is required to accept a @@ -1111,7 +1407,7 @@ int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt, /** * Open an input stream and read the header. The codecs are not opened. - * The stream must be closed with av_close_input_file(). + * The stream must be closed with avformat_close_input(). * * @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context). * May be a pointer to NULL, in which case an AVFormatContext is allocated by this @@ -1184,18 +1480,6 @@ int av_find_best_stream(AVFormatContext *ic, AVCodec **decoder_ret, int flags); -/** - * Read a transport packet from a media file. - * - * This function is obsolete and should never be used. - * Use av_read_frame() instead. - * - * @param s media file handle - * @param pkt is filled - * @return 0 if OK, AVERROR_xxx on error - */ -int av_read_packet(AVFormatContext *s, AVPacket *pkt); - /** * Return the next frame of a stream. * This function returns what is stored in the file, and does not validate @@ -1204,13 +1488,13 @@ int av_read_packet(AVFormatContext *s, AVPacket *pkt); * omit invalid data between valid frames so as to give the decoder the maximum * information possible for decoding. * - * The returned packet is valid - * until the next av_read_frame() or until av_close_input_file() and - * must be freed with av_free_packet. For video, the packet contains - * exactly one frame. For audio, it contains an integer number of - * frames if each frame has a known fixed size (e.g. PCM or ADPCM - * data). If the audio frames have a variable size (e.g. MPEG audio), - * then it contains one frame. + * If pkt->buf is NULL, then the packet is valid until the next + * av_read_frame() or until avformat_close_input(). Otherwise the packet + * is valid indefinitely. In both cases the packet must be freed with + * av_free_packet when it is no longer needed. For video, the packet contains + * exactly one frame. For audio, it contains an integer number of frames if each + * frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames + * have a variable size (e.g. MPEG audio), then it contains one frame. * * pkt->pts, pkt->dts and pkt->duration are always set to correct * values in AVStream.time_base units (and guessed if the format cannot @@ -1225,6 +1509,8 @@ int av_read_frame(AVFormatContext *s, AVPacket *pkt); /** * Seek to the keyframe at timestamp. * 'timestamp' in 'stream_index'. + * + * @param s media file handle * @param stream_index If stream_index is (-1), a default * stream is selected, and timestamp is automatically converted * from AV_TIME_BASE units to the stream specific time_base. @@ -1251,6 +1537,7 @@ int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as * keyframes (this may not be supported by all demuxers). * + * @param s media file handle * @param stream_index index of the stream which is used as time base reference * @param min_ts smallest acceptable timestamp * @param ts target timestamp @@ -1277,17 +1564,6 @@ int av_read_play(AVFormatContext *s); */ int av_read_pause(AVFormatContext *s); -#if FF_API_CLOSE_INPUT_FILE -/** - * @deprecated use avformat_close_input() - * Close a media file (but not its codecs). - * - * @param s media file handle - */ -attribute_deprecated -void av_close_input_file(AVFormatContext *s); -#endif - /** * Close an opened input AVFormatContext. Free it and all its contents * and set *s to NULL. @@ -1312,7 +1588,7 @@ void avformat_close_input(AVFormatContext **s); * * @param s Media file handle, must be allocated with avformat_alloc_context(). * Its oformat field must be set to the desired output format; - * Its pb field must be set to an already openened AVIOContext. + * Its pb field must be set to an already opened AVIOContext. * @param options An AVDictionary filled with AVFormatContext and muxer-private options. * On return this parameter will be destroyed and replaced with a dict containing * options that were not found. May be NULL. @@ -1326,70 +1602,75 @@ int avformat_write_header(AVFormatContext *s, AVDictionary **options); /** * Write a packet to an output media file. * - * The packet shall contain one audio or video frame. - * The packet must be correctly interleaved according to the container - * specification, if not then av_interleaved_write_frame must be used. + * This function passes the packet directly to the muxer, without any buffering + * or reordering. The caller is responsible for correctly interleaving the + * packets if the format requires it. Callers that want libavformat to handle + * the interleaving should call av_interleaved_write_frame() instead of this + * function. * * @param s media file handle - * @param pkt The packet, which contains the stream_index, buf/buf_size, - * dts/pts, ... - * This can be NULL (at any time, not just at the end), in - * order to immediately flush data buffered within the muxer, - * for muxers that buffer up data internally before writing it - * to the output. + * @param pkt The packet containing the data to be written. Note that unlike + * av_interleaved_write_frame(), this function does not take + * ownership of the packet passed to it (though some muxers may make + * an internal reference to the input packet). + *
+ * This parameter can be NULL (at any time, not just at the end), in + * order to immediately flush data buffered within the muxer, for + * muxers that buffer up data internally before writing it to the + * output. + *
+ * Packet's @ref AVPacket.stream_index "stream_index" field must be + * set to the index of the corresponding stream in @ref + * AVFormatContext.streams "s->streams". It is very strongly + * recommended that timing information (@ref AVPacket.pts "pts", @ref + * AVPacket.dts "dts", @ref AVPacket.duration "duration") is set to + * correct values. * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush + * + * @see av_interleaved_write_frame() */ int av_write_frame(AVFormatContext *s, AVPacket *pkt); /** * Write a packet to an output media file ensuring correct interleaving. * - * The packet must contain one audio or video frame. - * If the packets are already correctly interleaved, the application should - * call av_write_frame() instead as it is slightly faster. It is also important - * to keep in mind that completely non-interleaved input will need huge amounts - * of memory to interleave with this, so it is preferable to interleave at the - * demuxer level. + * This function will buffer the packets internally as needed to make sure the + * packets in the output file are properly interleaved in the order of + * increasing dts. Callers doing their own interleaving should call + * av_write_frame() instead of this function. * * @param s media file handle - * @param pkt The packet containing the data to be written. Libavformat takes - * ownership of the data and will free it when it sees fit using the packet's - * @ref AVPacket.destruct "destruct" field. The caller must not access the data - * after this function returns, as it may already be freed. - * Packet's @ref AVPacket.stream_index "stream_index" field must be set to the - * index of the corresponding stream in @ref AVFormatContext.streams - * "s.streams". - * It is very strongly recommended that timing information (@ref AVPacket.pts - * "pts", @ref AVPacket.dts "dts" @ref AVPacket.duration "duration") is set to - * correct values. - * - * @return 0 on success, a negative AVERROR on error. + * @param pkt The packet containing the data to be written. + *
+ * If the packet is reference-counted, this function will take + * ownership of this reference and unreference it later when it sees + * fit. + * The caller must not access the data through this reference after + * this function returns. If the packet is not reference-counted, + * libavformat will make a copy. + *
+ * This parameter can be NULL (at any time, not just at the end), to + * flush the interleaving queues. + *
+ * Packet's @ref AVPacket.stream_index "stream_index" field must be + * set to the index of the corresponding stream in @ref + * AVFormatContext.streams "s->streams". It is very strongly + * recommended that timing information (@ref AVPacket.pts "pts", @ref + * AVPacket.dts "dts", @ref AVPacket.duration "duration") is set to + * correct values. + * + * @return 0 on success, a negative AVERROR on error. Libavformat will always + * take care of freeing the packet, even if this function fails. + * + * @see av_write_frame(), AVFormatContext.max_interleave_delta */ int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt); -/** - * Interleave a packet per dts in an output media file. - * - * Packets with pkt->destruct == av_destruct_packet will be freed inside this - * function, so they cannot be used after it. Note that calling av_free_packet() - * on them is still safe. - * - * @param s media file handle - * @param out the interleaved packet will be output here - * @param pkt the input packet - * @param flush 1 if no further packets are available as input and all - * remaining packets should be output - * @return 1 if a packet was output, 0 if no packet could be output, - * < 0 if an error occurred - */ -int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out, - AVPacket *pkt, int flush); - /** * Write the stream trailer to an output media file and free the * file private data. * - * May only be called after a successful call to av_write_header. + * May only be called after a successful call to avformat_write_header. * * @param s media file handle * @return 0 if OK, AVERROR_xxx on error @@ -1415,7 +1696,7 @@ AVOutputFormat *av_guess_format(const char *short_name, /** * Guess the codec ID based upon muxer and filename. */ -enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, +enum AVCodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, const char *filename, const char *mime_type, enum AVMediaType type); @@ -1429,7 +1710,7 @@ enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, * @ingroup libavf * @{ * - * Miscelaneous utility functions related to both muxing and demuxing + * Miscellaneous utility functions related to both muxing and demuxing * (or neither). */ @@ -1442,7 +1723,7 @@ enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, * * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2 */ -void av_hex_dump(FILE *f, uint8_t *buf, int size); +void av_hex_dump(FILE *f, const uint8_t *buf, int size); /** * Send a nice hexadecimal dump of a buffer to the log. @@ -1456,7 +1737,7 @@ void av_hex_dump(FILE *f, uint8_t *buf, int size); * * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2 */ -void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size); +void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size); /** * Send a nice dump of a packet to the specified file stream. @@ -1484,13 +1765,14 @@ void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload, AVStream *st); /** - * Get the CodecID for the given codec tag tag. - * If no codec id is found returns CODEC_ID_NONE. + * Get the AVCodecID for the given codec tag tag. + * If no codec id is found returns AV_CODEC_ID_NONE. * * @param tags list of supported codec_id-codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag + * @param tag codec tag to match to a codec ID */ -enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag); +enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag); /** * Get the codec tag for the given codec id id. @@ -1498,13 +1780,17 @@ enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int * * @param tags list of supported codec_id-codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag + * @param id codec ID to match to a codec tag */ -unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id); +unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id); int av_find_default_stream_index(AVFormatContext *s); /** * Get the index for a specific timestamp. + * + * @param st stream that the timestamp belongs to + * @param timestamp timestamp to retrieve the index for * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond * to the timestamp which is <= the requested one, if backward * is 0, then it will be >= @@ -1550,16 +1836,21 @@ void av_url_split(char *proto, int proto_size, const char *url); +/** + * Print detailed information about the input or output format, such as + * duration, bitrate, streams, container, programs, metadata, side data, + * codec and time base. + * + * @param ic the context to analyze + * @param index the index to print, if you have multiple inputs or outputs + * @param url the URL to print, such as source or destination file + * @param is_output whether the context is input or ouput + */ void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output); -/** - * Get the current time in microseconds. - */ -int64_t av_gettime(void); - /** * Return in 'buf' the path with '%d' replaced by a number. * @@ -1586,6 +1877,9 @@ int av_filename_number_test(const char *filename); /** * Generate an SDP for an RTP session. * + * Note, this overwrites the id values of AVStreams in the muxer contexts + * for getting unique dynamic payload types. + * * @param ac array of AVFormatContexts describing the RTP streams. If the * array is composed by only one context, such context can contain * multiple AVStreams (one AVStream per RTP stream). Otherwise, @@ -1603,6 +1897,7 @@ int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size); * Return a positive value if the given filename has one of the given * extensions, 0 otherwise. * + * @param filename file name to check against the given extensions * @param extensions a comma-separated list of filename extensions */ int av_match_ext(const char *filename, const char *extensions); @@ -1610,31 +1905,34 @@ int av_match_ext(const char *filename, const char *extensions); /** * Test if the given container can store a codec. * + * @param ofmt container to check for compatibility + * @param codec_id codec to potentially store in container * @param std_compliance standards compliance level, one of FF_COMPLIANCE_* * * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot. * A negative number if this information is not available. */ -int avformat_query_codec(AVOutputFormat *ofmt, enum CodecID codec_id, int std_compliance); +int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, + int std_compliance); /** * @defgroup riff_fourcc RIFF FourCCs * @{ - * Get the tables mapping RIFF FourCCs to libavcodec CodecIDs. The tables are + * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the * following code: * @code * uint32_t tag = MKTAG('H', '2', '6', '4'); * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 }; - * enum CodecID id = av_codec_get_id(table, tag); + * enum AVCodecID id = av_codec_get_id(table, tag); * @endcode */ /** - * @return the table mapping RIFF FourCCs for video to libavcodec CodecID. + * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID. */ const struct AVCodecTag *avformat_get_riff_video_tags(void); /** - * @return the table mapping RIFF FourCCs for audio to CodecID. + * @return the table mapping RIFF FourCCs for audio to AVCodecID. */ const struct AVCodecTag *avformat_get_riff_audio_tags(void); /**