/* * copyright (c) 2001 Fabrice Bellard * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVFORMAT_AVFORMAT_H #define AVFORMAT_AVFORMAT_H /** * @file * @ingroup libavf * Main libavformat public API header */ /** * @defgroup libavf I/O and Muxing/Demuxing Library * @{ * * Libavformat (lavf) is a library for dealing with various media container * formats. Its main two purposes are demuxing - i.e. splitting a media file * into component streams, and the reverse process of muxing - writing supplied * data in a specified container format. It also has an @ref lavf_io * "I/O module" which supports a number of protocols for accessing the data (e.g. * file, tcp, http and others). Before using lavf, you need to call * av_register_all() to register all compiled muxers, demuxers and protocols. * Unless you are absolutely sure you won't use libavformat's network * capabilities, you should also call avformat_network_init(). * * A supported input format is described by an AVInputFormat struct, conversely * an output format is described by AVOutputFormat. You can iterate over all * registered input/output formats using the av_iformat_next() / * av_oformat_next() functions. The protocols layer is not part of the public * API, so you can only get the names of supported protocols with the * avio_enum_protocols() function. * * Main lavf structure used for both muxing and demuxing is AVFormatContext, * which exports all information about the file being read or written. As with * most Libavformat structures, its size is not part of public ABI, so it cannot be * allocated on stack or directly with av_malloc(). To create an * AVFormatContext, use avformat_alloc_context() (some functions, like * avformat_open_input() might do that for you). * * Most importantly an AVFormatContext contains: * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat * "output" format. It is either autodetected or set by user for input; * always set by user for output. * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all * elementary streams stored in the file. AVStreams are typically referred to * using their index in this array. * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or * 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 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. * * @section lavf_decoding_open Opening a media file * The minimum information required to open a file is its URL or filename, which * is passed to avformat_open_input(), as in the following code: * @code * const char *url = "in.mp3"; * AVFormatContext *s = NULL; * int ret = avformat_open_input(&s, url, NULL, NULL); * if (ret < 0) * abort(); * @endcode * The above code attempts to allocate an AVFormatContext, open the * specified file (autodetecting the format) and read the header, exporting the * information stored there into s. Some formats do not have a header or do not * store enough information there, so it is recommended that you call the * avformat_find_stream_info() function which tries to read and decode a few * frames to find missing information. * * In some cases you might want to preallocate an AVFormatContext yourself with * avformat_alloc_context() and do some tweaking on it before passing it to * avformat_open_input(). One such case is when you want to use custom functions * for reading input data instead of lavf internal I/O layer. * To do that, create your own AVIOContext with avio_alloc_context(), passing * 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. * * The packet data belongs to the demuxer and is invalid after the next call to * av_read_frame(). The user must free the packet with av_free_packet() before * calling av_read_frame() again or closing the file. * * @section lavf_decoding_seek Seeking * @} * * @defgroup lavf_encoding Muxing * @{ * @} * * @defgroup lavf_io I/O Read/Write * @{ * @} * * @defgroup lavf_codec Demuxers * @{ * @defgroup lavf_codec_native Native Demuxers * @{ * @} * @defgroup lavf_codec_wrappers External library wrappers * @{ * @} * @} * @defgroup lavf_protos I/O Protocols * @{ * @} * @defgroup lavf_internal Internal * @{ * @} * @} * */ #include #include /* FILE */ #include "libavcodec/avcodec.h" #include "libavutil/dict.h" #include "libavutil/log.h" #include "avio.h" #include "libavformat/version.h" struct AVFormatContext; /** * @defgroup metadata_api Public Metadata API * @{ * @ingroup libavf * The metadata API allows libavformat to export metadata tags to a client * application when demuxing. Conversely it allows a client application to * set metadata when muxing. * * Metadata is exported or set as pairs of key/value strings in the 'metadata' * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg, * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata * exported by demuxers isn't checked to be valid UTF-8 in most cases. * * Important concepts to keep in mind: * - Keys are unique; there can never be 2 tags with the same key. This is * also meant semantically, i.e., a demuxer should not knowingly produce * several keys that are literally different but semantically identical. * E.g., key=Author5, key=Author6. In this example, all authors must be * placed in the same tag. * - Metadata is flat, not hierarchical; there are no subtags. If you * want to store, e.g., the email address of the child of producer Alice * and actor Bob, that could have key=alice_and_bobs_childs_email_address. * - Several modifiers can be applied to the tag name. This is done by * appending a dash character ('-') and the modifier name in the order * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng. * - language -- a tag whose value is localized for a particular language * is appended with the ISO 639-2/B 3-letter language code. * For example: Author-ger=Michael, Author-eng=Mike * The original/default language is in the unqualified "Author" tag. * A demuxer should set a default if it sets any translated tag. * - 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". * * - Demuxers attempt to export metadata in a generic format, however tags * with no generic equivalents are left as they are stored in the container. * Follows a list of generic tag names: * @verbatim album -- name of the set this work belongs to album_artist -- main creator of the set/album, if different from artist. e.g. "Various Artists" for compilation albums. artist -- main creator of the work comment -- any additional description of the file. composer -- who composed the work, if different from artist. copyright -- name of copyright holder. creation_time-- date when the file was created, preferably in ISO 8601. date -- date when the work was created, preferably in ISO 8601. disc -- number of a subset, e.g. disc in a multi-disc collection. encoder -- name/settings of the software/hardware that produced the file. encoded_by -- person/group who created the file. filename -- original name of the file. genre -- . language -- main language in which the work is performed, preferably in ISO 639-2 format. Multiple languages can be specified by separating them with commas. performer -- artist who performed the work, if different from artist. E.g for "Also sprach Zarathustra", artist would be "Richard Strauss" and performer "London Philharmonic Orchestra". publisher -- name of the label/publisher. service_name -- name of the service in broadcasting (channel name). service_provider -- name of the service provider in broadcasting. title -- name of the work. track -- number of this work in the set, can be in form current/total. variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of @endverbatim * * Look in the examples section for an application example how to use the Metadata API. * * @} */ /* packet functions */ /** * Allocate and read the payload of a packet and initialize its * fields with default values. * * @param pkt packet * @param size desired payload size * @return >0 (read size) if OK, AVERROR_xxx otherwise */ int av_get_packet(AVIOContext *s, AVPacket *pkt, int size); /** * Read data and append it to the current content of the AVPacket. * If pkt->size is 0 this is identical to av_get_packet. * Note that this uses av_grow_packet and thus involves a realloc * which is inefficient. Thus this function should only be used * when there is no reasonable way to know (an upper bound of) * the final size. * * @param pkt packet * @param size amount of data to read * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data * will not be lost even if an error occurs. */ int av_append_packet(AVIOContext *s, AVPacket *pkt, int size); /*************************************************/ /* fractional numbers for exact pts handling */ /** * The exact value of the fractional number is: 'val + num / den'. * num is assumed to be 0 <= num < den. */ typedef struct AVFrac { int64_t val, num, den; } AVFrac; /*************************************************/ /* input/output formats */ struct AVCodecTag; /** * This structure contains the data a format has to probe a file. */ 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 */ } AVProbeData; #define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection #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. */ #define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for raw picture data. */ #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. */ #define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */ #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_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. */ #if LIBAVFORMAT_VERSION_MAJOR <= 54 #define AVFMT_TS_NONSTRICT 0x8020000 //we try to be compatible to the ABIs of ffmpeg and major forks #else #define AVFMT_TS_NONSTRICT 0x20000 #endif /**< Format does not require strictly increasing timestamps, but they must still be monotonic */ #define AVFMT_SEEK_TO_PTS 0x4000000 /**< Seeking is based on PTS */ /** * @addtogroup lavf_encoding * @{ */ typedef struct AVOutputFormat { const char *name; /** * Descriptive name for the format, meant to be more human-readable * than name. You should use the NULL_IF_CONFIG_SMALL() macro * to define it. */ const char *long_name; 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 */ /** * can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE, * AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS, * 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. */ const struct AVCodecTag * const *codec_tag; const AVClass *priv_class; ///< AVClass for the private context /***************************************************************** * No fields below this line are 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. ***************************************************************** */ struct AVOutputFormat *next; /** * size of private data so that it can be allocated in the wrapper */ int priv_data_size; int (*write_header)(struct AVFormatContext *); /** * Write a packet. If AVFMT_ALLOW_FLUSH is set in flags, * pkt can be NULL in order to flush data buffered in the muxer. * When flushing, return 0 if there still is more data to flush, * or 1 if everything was flushed and there is no more buffered * data. */ int (*write_packet)(struct AVFormatContext *, AVPacket *pkt); int (*write_trailer)(struct AVFormatContext *); /** * Currently only used to set pixel format if not YUV420P. */ int (*interleave_packet)(struct AVFormatContext *, AVPacket *out, AVPacket *in, int flush); /** * Test if the given codec can be stored in this container. * * @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); void (*get_output_timestamp)(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall); } AVOutputFormat; /** * @} */ /** * @addtogroup lavf_decoding * @{ */ typedef struct AVInputFormat { /** * A comma separated list of short names for the format. New names * may be appended with a minor bump. */ const char *name; /** * Descriptive name for the format, meant to be more human-readable * than name. You should use the NULL_IF_CONFIG_SMALL() macro * to define it. */ const char *long_name; /** * Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS, * AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH, * AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK, AVFMT_SEEK_TO_PTS. */ int flags; /** * If extensions are defined, then no probe is done. You should * usually not use extension format guessing because it is not * reliable enough */ const char *extensions; const struct AVCodecTag * const *codec_tag; const AVClass *priv_class; ///< AVClass for the private context /***************************************************************** * No fields below this line are 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. ***************************************************************** */ struct AVInputFormat *next; /** * Raw demuxers store their codec ID here. */ int raw_codec_id; /** * Size of private data so that it can be allocated in the wrapper. */ int priv_data_size; /** * Tell if a given file has a chance of being parsed as this format. * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes * big so you do not have to check for that unless you need more. */ int (*read_probe)(AVProbeData *); /** * 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. */ int (*read_header)(struct AVFormatContext *); /** * Read one packet and put it in 'pkt'. pts and flags are also * set. 'avformat_new_stream' can be called only if the flag * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a * background thread). * @return 0 on success, < 0 on error. * When returning an error, pkt must not have been allocated * or must be freed before returning */ int (*read_packet)(struct AVFormatContext *, AVPacket *pkt); /** * Close the stream. The AVFormatContext and AVStreams are not * freed by this function */ int (*read_close)(struct AVFormatContext *); /** * Seek to a given timestamp relative to the frames in * stream component stream_index. * @param stream_index Must not be -1. * @param flags Selects which direction should be preferred if no exact * match is available. * @return >= 0 on success (but not necessarily the new offset) */ int (*read_seek)(struct AVFormatContext *, int stream_index, int64_t timestamp, int flags); /** * Get the next timestamp in stream[stream_index].time_base units. * @return the timestamp or AV_NOPTS_VALUE if an error occurred */ int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index, int64_t *pos, int64_t pos_limit); /** * Start/resume playing - only meaningful if using a network-based format * (RTSP). */ int (*read_play)(struct AVFormatContext *); /** * Pause playing - only meaningful if using a network-based format * (RTSP). */ int (*read_pause)(struct AVFormatContext *); /** * Seek to timestamp ts. * Seeking will be done so that the point from which all active streams * can be presented successfully will be closest to ts and within min/max_ts. * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL. */ int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags); } AVInputFormat; /** * @} */ enum AVStreamParseType { AVSTREAM_PARSE_NONE, AVSTREAM_PARSE_FULL, /**< full parsing and repack */ AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */ AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */ AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */ AVSTREAM_PARSE_FULL_RAW=MKTAG(0,'R','A','W'), /**< full parsing and repack with timestamp generation for raw */ }; typedef struct AVIndexEntry { int64_t pos; int64_t timestamp; /**< * Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are available * when seeking to this entry. That means preferable PTS on keyframe based formats. * But demuxers can choose to store a different timestamp, if it is more convenient for the implementation or nothing better * is known */ #define AVINDEX_KEYFRAME 0x0001 int flags:2; int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment). int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */ } AVIndexEntry; #define AV_DISPOSITION_DEFAULT 0x0001 #define AV_DISPOSITION_DUB 0x0002 #define AV_DISPOSITION_ORIGINAL 0x0004 #define AV_DISPOSITION_COMMENT 0x0008 #define AV_DISPOSITION_LYRICS 0x0010 #define AV_DISPOSITION_KARAOKE 0x0020 /** * Track should be used during playback by default. * Useful for subtitle track that should be displayed * even when user did not explicitly ask for subtitles. */ #define AV_DISPOSITION_FORCED 0x0040 #define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */ #define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */ #define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */ /** * The stream is stored in the file as an attached picture/"cover art" (e.g. * APIC frame in ID3v2). The single packet associated with it will be returned * among the first few packets read from the file unless seeking takes place. * It can also be accessed at any time in AVStream.attached_pic. */ #define AV_DISPOSITION_ATTACHED_PIC 0x0400 /** * Stream structure. * New fields can be added to the end with minor version bumps. * Removal, reordering and changes to existing fields require a major * version bump. * sizeof(AVStream) must not be used outside libav*. */ typedef struct AVStream { int index; /**< stream index in AVFormatContext */ /** * Format-specific stream ID. * decoding: set by libavformat * encoding: set by the user */ 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. */ AVCodecContext *codec; /** * 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. */ AVRational r_frame_rate; void *priv_data; /** * encoding: pts generation when outputting stream */ struct AVFrac pts; /** * This is the fundamental unit of time (in seconds) in terms * of which frame timestamps are represented. * * decoding: set by libavformat * encoding: set by libavformat in av_write_header. The muxer may use the * user-provided value of @ref AVCodecContext.time_base "codec->time_base" * as a hint. */ AVRational time_base; /** * Decoding: pts of the first frame of the stream in presentation order, in stream time base. * Only set this if you are absolutely 100% sure that the value you set * it to really is the pts of the first frame. * This may be undefined (AV_NOPTS_VALUE). * @note The ASF header does NOT contain a correct start_time the ASF * demuxer must NOT set this. */ int64_t start_time; /** * Decoding: duration of the stream, in stream time base. * If a source file does not specify a duration, but does specify * a bitrate, this value will be estimated from bitrate and file size. */ int64_t duration; int64_t nb_frames; ///< number of frames in this stream if known or 0 int disposition; /**< AV_DISPOSITION_* bit field */ enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed. /** * sample aspect ratio (0 if unknown) * - encoding: Set by user. * - decoding: Set by libavformat. */ AVRational sample_aspect_ratio; AVDictionary *metadata; /** * Average framerate */ AVRational avg_frame_rate; /** * For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet * will contain the attached picture. * * decoding: set by libavformat, must not be modified by the caller. * encoding: unused */ AVPacket attached_pic; /***************************************************************** * 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. ***************************************************************** */ /** * Stream information used internally by av_find_stream_info() */ #define MAX_STD_TIMEBASES (60*12+6) struct { int64_t last_dts; int64_t duration_gcd; int duration_count; double duration_error[2][2][MAX_STD_TIMEBASES]; int64_t codec_info_duration; int nb_decoded_frames; int found_decoder; } *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; int last_IP_duration; /** * Number of packets to buffer for codec probing */ #define MAX_PROBE_PACKETS 2500 int probe_packets; /** * Number of frames that have been demuxed during av_find_stream_info() */ int codec_info_nb_frames; /** * Stream Identifier * This is the MPEG-TS stream identifier +1 * 0 means unknown */ int stream_identifier; int64_t interleaver_chunk_size; int64_t interleaver_chunk_duration; /* av_read_frame() support */ enum AVStreamParseType need_parsing; struct AVCodecParserContext *parser; /** * last packet in packet_buffer for this stream when muxing. */ struct AVPacketList *last_in_packet_buffer; AVProbeData probe_data; #define MAX_REORDER_DELAY 16 int64_t pts_buffer[MAX_REORDER_DELAY+1]; AVIndexEntry *index_entries; /**< Only used if the format does not support seeking natively. */ int nb_index_entries; unsigned int index_entries_allocated_size; /** * flag to indicate that probing is requested * NOT PART OF PUBLIC API */ int request_probe; /** * Indicates that everything up to the next keyframe * should be discarded. */ int skip_to_keyframe; } AVStream; #define AV_PROGRAM_RUNNING 1 /** * New fields can be added to the end with minor version bumps. * Removal, reordering and changes to existing fields require a major * version bump. * sizeof(AVProgram) must not be used outside libav*. */ typedef struct AVProgram { int id; int flags; enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller unsigned int *stream_index; unsigned int nb_stream_indexes; AVDictionary *metadata; int program_num; int pmt_pid; int pcr_pid; } AVProgram; #define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present (streams are added dynamically) */ typedef struct AVChapter { int id; ///< unique ID to identify the chapter AVRational time_base; ///< time base in which the start/end timestamps are specified int64_t start, end; ///< chapter start/end time in time_base units AVDictionary *metadata; } AVChapter; /** * Format I/O context. * New fields can be added to the end with minor version bumps. * Removal, reordering and changes to existing fields require a major * version bump. * sizeof(AVFormatContext) must not be used outside libav*, use * avformat_alloc_context() to create an AVFormatContext. */ typedef struct AVFormatContext { /** * A class for logging and 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. * * decoding: set by avformat_open_input(). * encoding: set by the user. */ struct AVInputFormat *iformat; struct AVOutputFormat *oformat; /** * Format private data. This is an AVOptions-enabled struct * if and only if iformat/oformat.priv_class is not NULL. */ 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. * * Do NOT set this field if AVFMT_NOFILE flag is set in * iformat/oformat.flags. In such a case, the (de)muxer will handle * I/O in some other way and this field will be NULL. */ AVIOContext *pb; /* stream info */ int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */ /** * 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(). */ unsigned int nb_streams; AVStream **streams; char filename[1024]; /**< input or output filename */ /** * Decoding: 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. */ int64_t start_time; /** * Decoding: 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. */ int64_t duration; /** * Decoding: total stream bitrate in bit/s, 0 if not * available. Never set it directly if the file_size and the * duration are known as FFmpeg can compute it automatically. */ int bit_rate; unsigned int packet_size; int max_delay; int flags; #define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames. #define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index. #define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input. #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_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_MP4A_LATM 0x8000 ///< Enable RTP MP4A-LATM payload #define AVFMT_FLAG_SORT_DTS 0x10000 ///< try to interleave outputted packets by dts (using this flag can slow demuxing down) #define AVFMT_FLAG_PRIV_OPT 0x20000 ///< Enable use of private options by delaying codec open (this could be made default once all code is converted) #define AVFMT_FLAG_KEEP_SIDE_DATA 0x40000 ///< Dont merge side data but keep it separate. /** * decoding: size of data to probe; encoding: unused. */ unsigned int probesize; /** * decoding: maximum time (in AV_TIME_BASE units) during which the input should * be analyzed in avformat_find_stream_info(). */ int max_analyze_duration; const uint8_t *key; int keylen; unsigned int nb_programs; AVProgram **programs; /** * Forced video codec_id. * Demuxing: Set by user. */ enum CodecID video_codec_id; /** * Forced audio codec_id. * Demuxing: Set by user. */ enum CodecID audio_codec_id; /** * Forced subtitle codec_id. * Demuxing: Set by user. */ enum CodecID subtitle_codec_id; /** * Maximum amount of memory in bytes to use for the index of each stream. * If the index exceeds this size, entries will be discarded as * needed to maintain a smaller size. This can lead to slower or less * accurate seeking (depends on demuxer). * Demuxers for which a full in-memory index is mandatory will ignore * this. * muxing : unused * demuxing: set by user */ unsigned int max_index_size; /** * Maximum amount of memory in bytes to use for buffering frames * obtained from realtime capture devices. */ unsigned int max_picture_buffer; unsigned int nb_chapters; AVChapter **chapters; 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. */ int64_t start_time_realtime; /** * decoding: number of frames used to probe fps */ 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. */ 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() * (mainly useful for AVFMT_NOFILE formats). The callback * should also be passed to avio_open2() if it's used to * open the file. */ AVIOInterruptCB interrupt_callback; /** * Flags to enable debugging. */ int debug; #define FF_FDEBUG_TS 0x0001 /** * Transport stream id. * This will be moved into demuxer private options. Thus no API/ABI compatibility */ int ts_id; /** * Audio preload in microseconds. * Note, not all formats support this and unpredictable things may happen if it is used when not supported. * - encoding: Set by user via AVOptions (NO direct access) * - decoding: unused */ int audio_preload; /** * Max chunk time in microseconds. * Note, not all formats support this and unpredictable things may happen if it is used when not supported. * - encoding: Set by user via AVOptions (NO direct access) * - decoding: unused */ int max_chunk_duration; /** * Max chunk size in bytes * Note, not all formats support this and unpredictable things may happen if it is used when not supported. * - encoding: Set by user via AVOptions (NO direct access) * - decoding: unused */ int max_chunk_size; /***************************************************************** * 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. ***************************************************************** */ /** * This buffer is only needed when packets were already buffered but * not decoded, for example to get the codec parameters in MPEG * streams. */ struct AVPacketList *packet_buffer; struct AVPacketList *packet_buffer_end; /* av_seek_frame() support */ int64_t data_offset; /**< offset of the first packet */ /** * 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. */ struct AVPacketList *raw_packet_buffer; struct AVPacketList *raw_packet_buffer_end; /** * Packets split by the parser get queued here. */ struct AVPacketList *parse_queue; struct AVPacketList *parse_queue_end; /** * Remaining size available for raw_packet_buffer, in bytes. */ #define RAW_PACKET_BUFFER_SIZE 2500000 int raw_packet_buffer_remaining_size; int avio_flags; /** * The duration field can be estimated through various ways, and this field can be used * to know how the duration was estimated. */ enum { AVFMT_DURATION_FROM_PTS, ///< duration accurately estimated from PTSes AVFMT_DURATION_FROM_STREAM, ///< duration estimated from a stream with a known duration AVFMT_DURATION_FROM_BITRATE ///< duration estimated from bitrate (less accurate) } duration_estimation_method; } AVFormatContext; /** * Returns the method used to set ctx->duration. * * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE. */ int av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx); typedef struct AVPacketList { AVPacket pkt; struct AVPacketList *next; } AVPacketList; /** * @defgroup lavf_core Core functions * @ingroup libavf * * Functions for querying libavformat capabilities, allocating core structures, * etc. * @{ */ /** * Return the LIBAVFORMAT_VERSION_INT constant. */ unsigned avformat_version(void); /** * Return the libavformat build-time configuration. */ const char *avformat_configuration(void); /** * Return the libavformat license. */ const char *avformat_license(void); /** * Initialize libavformat and register all the muxers, demuxers and * protocols. If you do not call this function, then you can select * exactly which formats you want to support. * * @see av_register_input_format() * @see av_register_output_format() * @see av_register_protocol() */ void av_register_all(void); void av_register_input_format(AVInputFormat *format); void av_register_output_format(AVOutputFormat *format); /** * Do global initialization of network components. This is optional, * but recommended, since it avoids the overhead of implicitly * doing the setup for each session. * * Calling this function will become mandatory if using network * protocols at some major version bump. */ int avformat_network_init(void); /** * Undo the initialization done by avformat_network_init. */ int avformat_network_deinit(void); /** * If f is NULL, returns the first registered input format, * 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); /** * 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); /** * Allocate an AVFormatContext. * avformat_free_context() can be used to free the context and everything * allocated by the framework within it. */ AVFormatContext *avformat_alloc_context(void); /** * Free an AVFormatContext and all its streams. * @param s context to free */ void avformat_free_context(AVFormatContext *s); /** * Get the AVClass for AVFormatContext. It can be used in combination with * AV_OPT_SEARCH_FAKE_OBJ for examining options. * * @see av_opt_find(). */ const AVClass *avformat_get_class(void); /** * Add a new stream to a media file. * * When demuxing, it is called by the demuxer in read_header(). If the * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also * be called in read_packet(). * * When muxing, should be called by the user before avformat_write_header(). * * @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); AVProgram *av_new_program(AVFormatContext *s, int id); /** * @} */ #if FF_API_PKT_DUMP attribute_deprecated void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload); attribute_deprecated void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload); #endif #if FF_API_ALLOC_OUTPUT_CONTEXT /** * @deprecated deprecated in favor of avformat_alloc_output_context2() */ attribute_deprecated AVFormatContext *avformat_alloc_output_context(const char *format, AVOutputFormat *oformat, const char *filename); #endif /** * Allocate an AVFormatContext for an output format. * avformat_free_context() can be used to free the context and * everything allocated by the framework within it. * * @param *ctx is set to the created format context, or to NULL in * case of failure * @param oformat format to use for allocating the context, if NULL * format_name and filename are used instead * @param format_name the name of output format to use for allocating the * context, if NULL filename is used instead * @param filename the name of the filename to use for allocating the * context, may be NULL * @return >= 0 in case of success, a negative AVERROR code in case of * failure */ int avformat_alloc_output_context2(AVFormatContext **ctx, AVOutputFormat *oformat, const char *format_name, const char *filename); /** * @addtogroup lavf_decoding * @{ */ /** * Find AVInputFormat based on the short name of the input format. */ AVInputFormat *av_find_input_format(const char *short_name); /** * Guess the file format. * * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. */ AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened); /** * Guess the file format. * * @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 * detection, the variable is set to the actual detection * score afterwards. * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended * to retry with a larger probe buffer. */ AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max); /** * Guess the file format. * * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. * @param score_ret The score of the best detection. */ AVInputFormat *av_probe_input_format3(AVProbeData *pd, int is_opened, int *score_ret); /** * Probe a bytestream to determine the input format. Each time a probe returns * with a score that is too low, the probe buffer size is increased and another * attempt is made. When the maximum probe size is reached, the input format * with the highest score is returned. * * @param pb the bytestream to probe * @param fmt the input format is put here * @param filename the filename of the stream * @param logctx the log context * @param offset the offset within the bytestream to probe from * @param max_probe_size the maximum probe buffer size (zero for default) * @return 0 in case of success, a negative value corresponding to an * AVERROR code otherwise */ int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt, const char *filename, void *logctx, unsigned int offset, unsigned int max_probe_size); /** * Open an input stream and read the header. The codecs are not opened. * The stream must be closed with av_close_input_file(). * * @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 * function and written into ps. * Note that a user-supplied AVFormatContext will be freed on failure. * @param filename Name of the stream to open. * @param fmt If non-NULL, this parameter forces a specific input format. * Otherwise the format is autodetected. * @param options A dictionary filled with AVFormatContext and demuxer-private options. * On return this parameter will be destroyed and replaced with a dict containing * options that were not found. May be NULL. * * @return 0 on success, a negative AVERROR on failure. * * @note If you want to use custom IO, preallocate the format context and set its pb field. */ int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options); attribute_deprecated int av_demuxer_open(AVFormatContext *ic); #if FF_API_FORMAT_PARAMETERS /** * Read packets of a media file to get stream information. This * is useful for file formats with no headers such as MPEG. This * function also computes the real framerate in case of MPEG-2 repeat * frame mode. * The logical file position is not changed by this function; * examined packets may be buffered for later processing. * * @param ic media file handle * @return >=0 if OK, AVERROR_xxx on error * @todo Let the user decide somehow what information is needed so that * we do not waste time getting stuff the user does not need. * * @deprecated use avformat_find_stream_info. */ attribute_deprecated int av_find_stream_info(AVFormatContext *ic); #endif /** * Read packets of a media file to get stream information. This * is useful for file formats with no headers such as MPEG. This * function also computes the real framerate in case of MPEG-2 repeat * frame mode. * The logical file position is not changed by this function; * examined packets may be buffered for later processing. * * @param ic media file handle * @param options If non-NULL, an ic.nb_streams long array of pointers to * dictionaries, where i-th member contains options for * codec corresponding to i-th stream. * On return each dictionary will be filled with options that were not found. * @return >=0 if OK, AVERROR_xxx on error * * @note this function isn't guaranteed to open all the codecs, so * options being non-empty at return is a perfectly normal behavior. * * @todo Let the user decide somehow what information is needed so that * we do not waste time getting stuff the user does not need. */ int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options); /** * Find the programs which belong to a given stream. * * @param ic media file handle * @param last the last found program, the search will start after this * program, or from the beginning if it is NULL * @param s stream index * @return the next program which belongs to s, NULL if no program is found or * the last program is not among the programs of ic. */ AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s); /** * Find the "best" stream in the file. * The best stream is determined according to various heuristics as the most * likely to be what the user expects. * If the decoder parameter is non-NULL, av_find_best_stream will find the * default decoder for the stream's codec; streams for which no decoder can * be found are ignored. * * @param ic media file handle * @param type stream type: video, audio, subtitles, etc. * @param wanted_stream_nb user-requested stream number, * or -1 for automatic selection * @param related_stream try to find a stream related (eg. in the same * program) to this one, or -1 if none * @param decoder_ret if non-NULL, returns the decoder for the * selected stream * @param flags flags; none are currently defined * @return the non-negative stream number in case of success, * AVERROR_STREAM_NOT_FOUND if no stream with the requested type * could be found, * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder * @note If av_find_best_stream returns successfully and decoder_ret is not * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec. */ int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, AVCodec **decoder_ret, int flags); #if FF_API_READ_PACKET /** * @deprecated use AVFMT_FLAG_NOFILLIN | AVFMT_FLAG_NOPARSE to read raw * unprocessed packets * * 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 */ attribute_deprecated int av_read_packet(AVFormatContext *s, AVPacket *pkt); #endif /** * Return the next frame of a stream. * This function returns what is stored in the file, and does not validate * that what is there are valid frames for the decoder. It will split what is * stored in the file into frames and return one for each call. It will not * 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. * * pkt->pts, pkt->dts and pkt->duration are always set to correct * values in AVStream.time_base units (and guessed if the format cannot * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format * has B-frames, so it is better to rely on pkt->dts if you do not * decompress the payload. * * @return 0 if OK, < 0 on error or end of file */ int av_read_frame(AVFormatContext *s, AVPacket *pkt); /** * Seek to the keyframe at timestamp. * 'timestamp' in 'stream_index'. * @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. * @param timestamp Timestamp in AVStream.time_base units * or, if no stream is specified, in AV_TIME_BASE units. * @param flags flags which select direction and seeking mode * @return >= 0 on success */ int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags); /** * Seek to timestamp ts. * Seeking will be done so that the point from which all active streams * can be presented successfully will be closest to ts and within min/max_ts. * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL. * * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and * are the file position (this may not be supported by all demuxers). * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames * in the stream with stream_index (this may not be supported by all demuxers). * Otherwise all timestamps are in units of the stream selected by stream_index * or if stream_index is -1, in AV_TIME_BASE units. * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as * keyframes (this may not be supported by all demuxers). * * @param stream_index index of the stream which is used as time base reference * @param min_ts smallest acceptable timestamp * @param ts target timestamp * @param max_ts largest acceptable timestamp * @param flags flags * @return >=0 on success, error code otherwise * * @note This is part of the new seek API which is still under construction. * Thus do not use this yet. It may change at any time, do not expect * ABI compatibility yet! */ int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags); /** * Start playing a network-based stream (e.g. RTSP stream) at the * current position. */ int av_read_play(AVFormatContext *s); /** * Pause a network-based stream (e.g. RTSP stream). * * Use av_read_play() to resume it. */ 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. */ void avformat_close_input(AVFormatContext **s); /** * @} */ #if FF_API_NEW_STREAM /** * Add a new stream to a media file. * * Can only be called in the read_header() function. If the flag * AVFMTCTX_NOHEADER is in the format context, then new streams * can be added in read_packet too. * * @param s media file handle * @param id file-format-dependent stream ID */ attribute_deprecated AVStream *av_new_stream(AVFormatContext *s, int id); #endif #if FF_API_SET_PTS_INFO /** * @deprecated this function is not supposed to be called outside of lavf */ attribute_deprecated void av_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den); #endif #define AVSEEK_FLAG_BACKWARD 1 ///< seek backward #define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes #define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes #define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number /** * @addtogroup lavf_encoding * @{ */ /** * Allocate the stream private data and write the stream header to * an output media file. * * @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. * @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. * * @return 0 on success, negative AVERROR on failure. * * @see av_opt_find, av_dict_set, avio_open, av_oformat_next. */ 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. * * @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. * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush */ 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. * * @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 * This can be NULL (at any time, not just at the end), to flush the * interleaving queues. * @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. */ int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt); #if FF_API_INTERLEAVE_PACKET /** * @deprecated this function was never meant to be called by the user * programs. */ attribute_deprecated int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out, AVPacket *pkt, int flush); #endif /** * 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. * * @param s media file handle * @return 0 if OK, AVERROR_xxx on error */ int av_write_trailer(AVFormatContext *s); /** * Return the output format in the list of registered output formats * which best matches the provided parameters, or return NULL if * there is no match. * * @param short_name if non-NULL checks if short_name matches with the * names of the registered formats * @param filename if non-NULL checks if filename terminates with the * extensions of the registered formats * @param mime_type if non-NULL checks if mime_type matches with the * MIME type of the registered formats */ AVOutputFormat *av_guess_format(const char *short_name, const char *filename, const char *mime_type); /** * Guess the codec ID based upon muxer and filename. */ enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name, const char *filename, const char *mime_type, enum AVMediaType type); /** * Get timing information for the data currently output. * The exact meaning of "currently output" depends on the format. * It is mostly relevant for devices that have an internal buffer and/or * work in real time. * @param s media file handle * @param stream stream in the media file * @param dts[out] DTS of the last packet output for the stream, in stream * time_base units * @param wall[out] absolute time when that packet whas output, * in microsecond * @return 0 if OK, AVERROR(ENOSYS) if the format does not support it * Note: some formats or devices may not allow to measure dts and wall * atomically. */ int av_get_output_timestamp(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall); /** * @} */ /** * @defgroup lavf_misc Utility functions * @ingroup libavf * @{ * * Miscelaneous utility functions related to both muxing and demuxing * (or neither). */ /** * Send a nice hexadecimal dump of a buffer to the specified file stream. * * @param f The file stream pointer where the dump should be sent to. * @param buf buffer * @param size buffer size * * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2 */ void av_hex_dump(FILE *f, uint8_t *buf, int size); /** * Send a nice hexadecimal dump of a buffer to the log. * * @param avcl A pointer to an arbitrary struct of which the first field is a * pointer to an AVClass struct. * @param level The importance level of the message, lower values signifying * higher importance. * @param buf buffer * @param size buffer 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); /** * Send a nice dump of a packet to the specified file stream. * * @param f The file stream pointer where the dump should be sent to. * @param pkt packet to dump * @param dump_payload True if the payload must be displayed, too. * @param st AVStream that the packet belongs to */ void av_pkt_dump2(FILE *f, AVPacket *pkt, int dump_payload, AVStream *st); /** * Send a nice dump of a packet to the log. * * @param avcl A pointer to an arbitrary struct of which the first field is a * pointer to an AVClass struct. * @param level The importance level of the message, lower values signifying * higher importance. * @param pkt packet to dump * @param dump_payload True if the payload must be displayed, too. * @param st AVStream that the packet belongs to */ 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. * * @param tags list of supported codec_id-codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag */ enum CodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag); /** * Get the codec tag for the given codec id id. * If no codec tag is found returns 0. * * @param tags list of supported codec_id-codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag */ unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum CodecID id); int av_find_default_stream_index(AVFormatContext *s); /** * Get the index for a specific timestamp. * @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 >= * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise * @return < 0 if no such timestamp could be found */ int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags); /** * Add an index entry into a sorted list. Update the entry if the list * already contains it. * * @param timestamp timestamp in the time base of the given stream */ int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags); /** * Split a URL string into components. * * The pointers to buffers for storing individual components may be null, * in order to ignore that component. Buffers for components not found are * set to empty strings. If the port is not found, it is set to a negative * value. * * @param proto the buffer for the protocol * @param proto_size the size of the proto buffer * @param authorization the buffer for the authorization * @param authorization_size the size of the authorization buffer * @param hostname the buffer for the host name * @param hostname_size the size of the hostname buffer * @param port_ptr a pointer to store the port number in * @param path the buffer for the path * @param path_size the size of the path buffer * @param url the URL to split */ void av_url_split(char *proto, int proto_size, char *authorization, int authorization_size, char *hostname, int hostname_size, int *port_ptr, char *path, int path_size, const char *url); void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output); #if FF_API_AV_GETTIME int64_t av_gettime(void); #endif /** * Return in 'buf' the path with '%d' replaced by a number. * * Also handles the '%0nd' format where 'n' is the total number * of digits and '%%'. * * @param buf destination buffer * @param buf_size destination buffer size * @param path numbered sequence string * @param number frame number * @return 0 if OK, -1 on format error */ int av_get_frame_filename(char *buf, int buf_size, const char *path, int number); /** * Check whether filename actually is a numbered sequence generator. * * @param filename possible numbered sequence string * @return 1 if a valid numbered sequence string, 0 otherwise */ int av_filename_number_test(const char *filename); /** * Generate an SDP for an RTP session. * * @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, * all the contexts in the array (an AVCodecContext per RTP stream) * must contain only one AVStream. * @param n_files number of AVCodecContexts contained in ac * @param buf buffer where the SDP will be stored (must be allocated by * the caller) * @param size the size of the buffer * @return 0 if OK, AVERROR_xxx on error */ 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 extensions a comma-separated list of filename extensions */ int av_match_ext(const char *filename, const char *extensions); /** * Test if the given container can store a codec. * * @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); /** * @defgroup riff_fourcc RIFF FourCCs * @{ * Get the tables mapping RIFF FourCCs to libavcodec CodecIDs. 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); * @endcode */ /** * @return the table mapping RIFF FourCCs for video to libavcodec CodecID. */ const struct AVCodecTag *avformat_get_riff_video_tags(void); /** * @return the table mapping RIFF FourCCs for audio to CodecID. */ const struct AVCodecTag *avformat_get_riff_audio_tags(void); /** * Guesses the sample aspect ratio of a frame, based on both the stream and the * frame aspect ratio. * * Since the frame aspect ratio is set by the codec but the stream aspect ratio * is set by the demuxer, these two may not be equal. This function tries to * return the value that you should use if you would like to display the frame. * * Basic logic is to use the stream aspect ratio if it is set to something sane * otherwise use the frame aspect ratio. This way a container setting, which is * usually easy to modify can override the coded value in the frames. * * @param format the format context which the stream is part of * @param stream the stream which the frame is part of * @param frame the frame with the aspect ratio to be determined * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea */ AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, AVFrame *frame); /** * @} */ /** * @} */ #endif /* AVFORMAT_AVFORMAT_H */