* 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 libavformat
* 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).
* 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
* input/output formats using the av_demuxer_iterate / av_muxer_iterate() 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
* It is possible to configure lavf 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.
*
* @section urls
* URL strings in libavformat are made of a scheme/protocol, a ':', and a
* scheme specific string. URLs without a scheme and ':' used for local files
* are supported but deprecated. "file:" should be used for local files.
*
* It is important that the scheme string is not taken from untrusted
* sources without checks.
*
* Note that some schemes/protocols are quite powerful, allowing access to
* both local and remote files, parts of them, concatenations of them, local
* audio and video devices and so on.
*
* @{
*
* @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, which
* is passed to avformat_open_input(), as in the following code:
* @code
* const char *url = "file: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_send_packet() 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.
*
* A packet returned by av_read_frame() is always reference-counted,
* i.e. AVPacket.buf is set and the user may keep it indefinitely.
* The packet must be freed with av_packet_unref() 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.codecpar "stream codec parameters" information, such as the
* codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.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
* AVCodecParameters, rather than using @ref avcodec_parameters_copy() 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
* @{
* @section lavf_io_dirlist Directory listing
* The directory listing API makes it possible to list files on remote servers.
*
* Some of possible use cases:
* - an "open file" dialog to choose files from a remote location,
* - a recursive media finder providing a player with an ability to play all
* files from a given directory.
*
* @subsection lavf_io_dirlist_open Opening a directory
* At first, a directory needs to be opened by calling avio_open_dir()
* supplied with a URL and, optionally, ::AVDictionary containing
* protocol-specific parameters. The function returns zero or positive
* integer and allocates AVIODirContext on success.
*
* @code
* AVIODirContext *ctx = NULL;
* if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) {
* fprintf(stderr, "Cannot open directory.\n");
* abort();
* }
* @endcode
*
* This code tries to open a sample directory using smb protocol without
* any additional parameters.
*
* @subsection lavf_io_dirlist_read Reading entries
* Each directory's entry (i.e. file, another directory, anything else
* within ::AVIODirEntryType) is represented by AVIODirEntry.
* Reading consecutive entries from an opened AVIODirContext is done by
* repeatedly calling avio_read_dir() on it. Each call returns zero or
* positive integer if successful. Reading can be stopped right after the
* NULL entry has been read -- it means there are no entries left to be
* read. The following code reads all entries from a directory associated
* with ctx and prints their names to standard output.
* @code
* AVIODirEntry *entry = NULL;
* for (;;) {
* if (avio_read_dir(ctx, &entry) < 0) {
* fprintf(stderr, "Cannot list directory.\n");
* abort();
* }
* if (!entry)
* break;
* printf("%s\n", entry->name);
* avio_free_directory_entry(&entry);
* }
* @endcode
* @}
*
* @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 <stdio.h>
#include "libavcodec/codec_par.h"
#include "libavcodec/defs.h"
#include "libavcodec/packet.h"
#include "libavutil/dict.h"
#include "libavutil/log.h"
#include "avio.h"
#include "libavformat/version_major.h"
#ifndef HAVE_AV_CONFIG_H
* to avoid unnecessary rebuilds. When included externally, keep including
* the full version information. */
#include "libavformat/version.h"
#include "libavutil/frame.h"
#include "libavcodec/codec.h"
#endif
struct AVFormatContext;
struct AVFrame;
* @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".
* - Some protocols and demuxers support metadata updates. After a successful
* call to av_read_frame(), 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.
* 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 -- <self-evident>.
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.
*
* @}
*/
* 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
*/
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 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
* will not be lost even if an error occurs.
*/
int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
struct AVCodecTag;
* This structure contains the data a format has to probe a file.
*/
typedef struct AVProbeData {
const char *filename;
unsigned char *buf;
int buf_size;
const char *mime_type;
} AVProbeData;
#define AVPROBE_SCORE_RETRY (AVPROBE_SCORE_MAX/4)
#define AVPROBE_SCORE_STREAM_RETRY (AVPROBE_SCORE_MAX/4-1)
#define AVPROBE_SCORE_EXTENSION 50
#define AVPROBE_SCORE_MIME 75
#define AVPROBE_SCORE_MAX 100
#define AVPROBE_PADDING_SIZE 32
#define AVFMT_NOFILE 0x0001
#define AVFMT_NEEDNUMBER 0x0002
* The muxer/demuxer is experimental and should be used with caution.
*
* - demuxers: will not be selected automatically by probing, must be specified
* explicitly.
*/
#define AVFMT_EXPERIMENTAL 0x0004
#define AVFMT_SHOW_IDS 0x0008
#define AVFMT_GLOBALHEADER 0x0040
#define AVFMT_NOTIMESTAMPS 0x0080
#define AVFMT_GENERIC_INDEX 0x0100
#define AVFMT_TS_DISCONT 0x0200
#define AVFMT_VARIABLE_FPS 0x0400
#define AVFMT_NODIMENSIONS 0x0800
#define AVFMT_NOSTREAMS 0x1000
#define AVFMT_NOBINSEARCH 0x2000
#define AVFMT_NOGENSEARCH 0x4000
#define AVFMT_NO_BYTE_SEEK 0x8000
#if FF_API_ALLOW_FLUSH
#define AVFMT_ALLOW_FLUSH 0x10000
#endif
#define AVFMT_TS_NONSTRICT 0x20000
increasing timestamps, but they must
still be monotonic */
#define AVFMT_TS_NEGATIVE 0x40000
timestamps. If not set the timestamp
will be shifted in av_write_frame and
av_interleaved_write_frame so they
start from 0.
The user or muxer can override this through
AVFormatContext.avoid_negative_ts
*/
#define AVFMT_SEEK_TO_PTS 0x4000000
* @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;
enum AVCodecID audio_codec;
enum AVCodecID video_codec;
enum AVCodecID subtitle_codec;
* can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER,
* AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
* AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS,
* AVFMT_TS_NONSTRICT, AVFMT_TS_NEGATIVE
*/
int flags;
* List of supported codec_id-codec_tag pairs, ordered by "better
* choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
*/
const struct AVCodecTag * const *codec_tag;
const AVClass *priv_class;
} 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_NOTIMESTAMPS, 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;
* 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;
} AVInputFormat;
* @}
*/
enum AVStreamParseType {
AVSTREAM_PARSE_NONE,
AVSTREAM_PARSE_FULL,
AVSTREAM_PARSE_HEADERS,
AVSTREAM_PARSE_TIMESTAMPS,
AVSTREAM_PARSE_FULL_ONCE,
AVSTREAM_PARSE_FULL_RAW,
this assumes that each packet in the file contains no demuxer level headers and
just codec level data, otherwise position generation would fail */
};
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
#define AVINDEX_DISCARD_FRAME 0x0002
* Flag is used to indicate which frame should be discarded after decoding.
*/
int flags:2;
int size:30;
int min_distance;
} AVIndexEntry;
* The stream should be chosen by default among other streams of the same type,
* unless the user has explicitly specified otherwise.
*/
#define AV_DISPOSITION_DEFAULT (1 << 0)
* The stream is not in original language.
*
* @note AV_DISPOSITION_ORIGINAL is the inverse of this disposition. At most
* one of them should be set in properly tagged streams.
* @note This disposition may apply to any stream type, not just audio.
*/
#define AV_DISPOSITION_DUB (1 << 1)
* The stream is in original language.
*
* @see the notes for AV_DISPOSITION_DUB
*/
#define AV_DISPOSITION_ORIGINAL (1 << 2)
* The stream is a commentary track.
*/
#define AV_DISPOSITION_COMMENT (1 << 3)
* The stream contains song lyrics.
*/
#define AV_DISPOSITION_LYRICS (1 << 4)
* The stream contains karaoke audio.
*/
#define AV_DISPOSITION_KARAOKE (1 << 5)
* 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 (1 << 6)
* The stream is intended for hearing impaired audiences.
*/
#define AV_DISPOSITION_HEARING_IMPAIRED (1 << 7)
* The stream is intended for visually impaired audiences.
*/
#define AV_DISPOSITION_VISUAL_IMPAIRED (1 << 8)
* The audio stream contains music and sound effects without voice.
*/
#define AV_DISPOSITION_CLEAN_EFFECTS (1 << 9)
* The stream is stored in the file as an attached picture/"cover art" (e.g.
* APIC frame in ID3v2). The first (usually only) 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 (1 << 10)
* The stream is sparse, and contains thumbnail images, often corresponding
* to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC.
*/
#define AV_DISPOSITION_TIMED_THUMBNAILS (1 << 11)
* The stream is intended to be mixed with a spatial audio track. For example,
* it could be used for narration or stereo music, and may remain unchanged by
* listener head rotation.
*/
#define AV_DISPOSITION_NON_DIEGETIC (1 << 12)
* The subtitle stream contains captions, providing a transcription and possibly
* a translation of audio. Typically intended for hearing-impaired audiences.
*/
#define AV_DISPOSITION_CAPTIONS (1 << 16)
* The subtitle stream contains a textual description of the video content.
* Typically intended for visually-impaired audiences or for the cases where the
* video cannot be seen.
*/
#define AV_DISPOSITION_DESCRIPTIONS (1 << 17)
* The subtitle stream contains time-aligned metadata that is not intended to be
* directly presented to the user.
*/
#define AV_DISPOSITION_METADATA (1 << 18)
* The stream is intended to be mixed with another stream before presentation.
* Used for example to signal the stream contains an image part of a HEIF grid,
* or for mix_type=0 in mpegts.
*/
#define AV_DISPOSITION_DEPENDENT (1 << 19)
* The video stream contains still images.
*/
#define AV_DISPOSITION_STILL_IMAGE (1 << 20)
* The video stream contains multiple layers, e.g. stereoscopic views (cf. H.264
* Annex G/H, or HEVC Annex F).
*/
#define AV_DISPOSITION_MULTILAYER (1 << 21)
* @return The AV_DISPOSITION_* flag corresponding to disp or a negative error
* code if disp does not correspond to a known stream disposition.
*/
int av_disposition_from_string(const char *disp);
* @param disposition a combination of AV_DISPOSITION_* values
* @return The string description corresponding to the lowest set bit in
* disposition. NULL when the lowest set bit does not correspond
* to a known disposition or when disposition is 0.
*/
const char *av_disposition_to_string(int disposition);
* Options for behavior on timestamp wrap detection.
*/
#define AV_PTS_WRAP_IGNORE 0
#define AV_PTS_WRAP_ADD_OFFSET 1
#define AV_PTS_WRAP_SUB_OFFSET -1
typedef struct AVMOVStts {
unsigned int count;
unsigned int duration;
} AVMOVStts;
typedef struct AVMOVCtts {
unsigned int count;
int duration;
} AVMOVCtts;
* 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 {
* A class for @ref avoptions. Set on stream creation.
*/
const AVClass *av_class;
int index;
* Format-specific stream ID.
* decoding: set by libavformat
* encoding: set by the user, replaced by libavformat if left unset
*/
int id;
* Codec parameters associated with this stream. Allocated and freed by
* libavformat in avformat_new_stream() and avformat_free_context()
* respectively.
*
* - demuxing: filled by libavformat on stream creation or in
* avformat_find_stream_info()
* - muxing: filled by the caller before avformat_write_header()
*/
AVCodecParameters *codecpar;
void *priv_data;
* This is the fundamental unit of time (in seconds) in terms
* of which frame timestamps are represented.
*
* decoding: set by libavformat
* 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;
* 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.
*
* Encoding: May be set by the caller before avformat_write_header() to
* provide a hint to the muxer about the estimated duration.
*/
int64_t duration;
int64_t nb_frames;
* Stream disposition - a combination of AV_DISPOSITION_* flags.
* - demuxing: set by libavformat when creating the stream or in
* avformat_find_stream_info().
* - muxing: may be set by the caller before avformat_write_header().
*/
int disposition;
enum AVDiscard discard;
* sample aspect ratio (0 if unknown)
* - encoding: Set by user.
* - decoding: Set by libavformat.
*/
AVRational sample_aspect_ratio;
AVDictionary *metadata;
* 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;
* 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;
#if FF_API_AVSTREAM_SIDE_DATA
* 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().
*
* @deprecated use AVStream's @ref AVCodecParameters.coded_side_data
* "codecpar side data".
*/
attribute_deprecated
AVPacketSideData *side_data;
* The number of elements in the AVStream.side_data array.
*
* @deprecated use AVStream's @ref AVCodecParameters.nb_coded_side_data
* "codecpar side data".
*/
attribute_deprecated
int nb_side_data;
#endif
* Flags indicating events happening on the stream, a combination of
* AVSTREAM_EVENT_FLAG_*.
*
* - demuxing: may be set by the demuxer in avformat_open_input(),
* avformat_find_stream_info() and av_read_frame(). Flags must be cleared
* by the user once the event has been handled.
* - muxing: may be set by the user after avformat_write_header(). to
* indicate a user-triggered event. The muxer will clear the flags for
* events it has handled in av_[interleaved]_write_frame().
*/
int event_flags;
* - demuxing: the demuxer read new metadata from the file and updated
* AVStream.metadata accordingly
* - muxing: the user updated AVStream.metadata and wishes the muxer to write
* it into the file
*/
#define AVSTREAM_EVENT_FLAG_METADATA_UPDATED 0x0001
* - demuxing: new packets for this stream were read from the file. This
* event is informational only and does not guarantee that new packets
* for this stream will necessarily be returned from av_read_frame().
*/
#define AVSTREAM_EVENT_FLAG_NEW_PACKETS (1 << 1)
* 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;
* Number of bits in timestamps. Used for wrapping control.
*
* - demuxing: set by libavformat
* - muxing: set by libavformat
*
*/
int pts_wrap_bits;
* Array derived from ffmpeg
*
* used to fetch stts_data and ctts_data of mov files
*/
unsigned int stts_count;
AVMOVStts *stts_data;
unsigned int ctts_count;
AVMOVCtts *ctts_data;
int time_scale;
} AVStream;
* AVStreamGroupTileGrid holds information on how to combine several
* independent images on a single canvas for presentation.
*
* The output should be a @ref AVStreamGroupTileGrid.background "background"
* colored @ref AVStreamGroupTileGrid.coded_width "coded_width" x
* @ref AVStreamGroupTileGrid.coded_height "coded_height" canvas where a
* @ref AVStreamGroupTileGrid.nb_tiles "nb_tiles" amount of tiles are placed in
* the order they appear in the @ref AVStreamGroupTileGrid.offsets "offsets"
* array, at the exact offset described for them. In particular, if two or more
* tiles overlap, the image with higher index in the
* @ref AVStreamGroupTileGrid.offsets "offsets" array takes priority.
* Note that a single image may be used multiple times, i.e. multiple entries
* in @ref AVStreamGroupTileGrid.offsets "offsets" may have the same value of
* idx.
*
* The following is an example of a simple grid with 3 rows and 4 columns:
*
* +---+---+---+---+
* | 0 | 1 | 2 | 3 |
* +---+---+---+---+
* | 4 | 5 | 6 | 7 |
* +---+---+---+---+
* | 8 | 9 |10 |11 |
* +---+---+---+---+
*
* Assuming all tiles have a dimension of 512x512, the
* @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
* the first @ref AVStreamGroup.streams "stream" in the group is "0,0", the
* @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
* the second @ref AVStreamGroup.streams "stream" in the group is "512,0", the
* @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of
* the fifth @ref AVStreamGroup.streams "stream" in the group is "0,512", the
* @ref AVStreamGroupTileGrid.offsets "offset", of the topleft pixel of
* the sixth @ref AVStreamGroup.streams "stream" in the group is "512,512",
* etc.
*
* The following is an example of a canvas with overlaping tiles:
*
* +-----------+
* | %%%%% |
* |***%%3%%@@@|
* |**0%%%%%2@@|
* |***##1@@@@@|
* | ##### |
* +-----------+
*
* Assuming a canvas with size 1024x1024 and all tiles with a dimension of
* 512x512, a possible @ref AVStreamGroupTileGrid.offsets "offset" for the
* topleft pixel of the first @ref AVStreamGroup.streams "stream" in the group
* would be 0x256, the @ref AVStreamGroupTileGrid.offsets "offset" for the
* topleft pixel of the second @ref AVStreamGroup.streams "stream" in the group
* would be 256x512, the @ref AVStreamGroupTileGrid.offsets "offset" for the
* topleft pixel of the third @ref AVStreamGroup.streams "stream" in the group
* would be 512x256, and the @ref AVStreamGroupTileGrid.offsets "offset" for
* the topleft pixel of the fourth @ref AVStreamGroup.streams "stream" in the
* group would be 256x0.
*
* sizeof(AVStreamGroupTileGrid) is not a part of the ABI and may only be
* allocated by avformat_stream_group_create().
*/
typedef struct AVStreamGroupTileGrid {
const AVClass *av_class;
* Amount of tiles in the grid.
*
* Must be > 0.
*/
unsigned int nb_tiles;
* Width of the canvas.
*
* Must be > 0.
*/
int coded_width;
* Width of the canvas.
*
* Must be > 0.
*/
int coded_height;
* An @ref nb_tiles sized array of offsets in pixels from the topleft edge
* of the canvas, indicating where each stream should be placed.
* It must be allocated with the av_malloc() family of functions.
*
* - demuxing: set by libavformat, must not be modified by the caller.
* - muxing: set by the caller before avformat_write_header().
*
* Freed by libavformat in avformat_free_context().
*/
struct {
* Index of the stream in the group this tile references.
*
* Must be < @ref AVStreamGroup.nb_streams "nb_streams".
*/
unsigned int idx;
* Offset in pixels from the left edge of the canvas where the tile
* should be placed.
*/
int horizontal;
* Offset in pixels from the top edge of the canvas where the tile
* should be placed.
*/
int vertical;
} *offsets;
* The pixel value per channel in RGBA format used if no pixel of any tile
* is located at a particular pixel location.
*
* @see av_image_fill_color().
* @see av_parse_color().
*/
uint8_t background[4];
* Offset in pixels from the left edge of the canvas where the actual image
* meant for presentation starts.
*
* This field must be >= 0 and < @ref coded_width.
*/
int horizontal_offset;
* Offset in pixels from the top edge of the canvas where the actual image
* meant for presentation starts.
*
* This field must be >= 0 and < @ref coded_height.
*/
int vertical_offset;
* Width of the final image for presentation.
*
* Must be > 0 and <= (@ref coded_width - @ref horizontal_offset).
* When it's not equal to (@ref coded_width - @ref horizontal_offset), the
* result of (@ref coded_width - width - @ref horizontal_offset) is the
* amount amount of pixels to be cropped from the right edge of the
* final image before presentation.
*/
int width;
* Height of the final image for presentation.
*
* Must be > 0 and <= (@ref coded_height - @ref vertical_offset).
* When it's not equal to (@ref coded_height - @ref vertical_offset), the
* result of (@ref coded_height - height - @ref vertical_offset) is the
* amount amount of pixels to be cropped from the bottom edge of the
* final image before presentation.
*/
int height;
} AVStreamGroupTileGrid;
* AVStreamGroupLCEVC is meant to define the relation between video streams
* and a data stream containing LCEVC enhancement layer NALUs.
*
* No more than one stream of @ref AVCodecParameters.codec_type "codec_type"
* AVMEDIA_TYPE_DATA shall be present, and it must be of
* @ref AVCodecParameters.codec_id "codec_id" AV_CODEC_ID_LCEVC.
*/
typedef struct AVStreamGroupLCEVC {
const AVClass *av_class;
* Index of the LCEVC data stream in AVStreamGroup.
*/
unsigned int lcevc_index;
* Width of the final stream for presentation.
*/
int width;
* Height of the final image for presentation.
*/
int height;
} AVStreamGroupLCEVC;
enum AVStreamGroupParamsType {
AV_STREAM_GROUP_PARAMS_NONE,
AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT,
AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION,
AV_STREAM_GROUP_PARAMS_TILE_GRID,
AV_STREAM_GROUP_PARAMS_LCEVC,
};
struct AVIAMFAudioElement;
struct AVIAMFMixPresentation;
typedef struct AVStreamGroup {
* A class for @ref avoptions. Set by avformat_stream_group_create().
*/
const AVClass *av_class;
void *priv_data;
* Group index in AVFormatContext.
*/
unsigned int index;
* Group type-specific group ID.
*
* decoding: set by libavformat
* encoding: may set by the user
*/
int64_t id;
* Group type
*
* decoding: set by libavformat on group creation
* encoding: set by avformat_stream_group_create()
*/
enum AVStreamGroupParamsType type;
* Group type-specific parameters
*/
union {
struct AVIAMFAudioElement *iamf_audio_element;
struct AVIAMFMixPresentation *iamf_mix_presentation;
struct AVStreamGroupTileGrid *tile_grid;
struct AVStreamGroupLCEVC *lcevc;
} params;
* Metadata that applies to the whole group.
*
* - demuxing: set by libavformat on group creation
* - muxing: may be set by the caller before avformat_write_header()
*
* Freed by libavformat in avformat_free_context().
*/
AVDictionary *metadata;
* Number of elements in AVStreamGroup.streams.
*
* Set by avformat_stream_group_add_stream() must not be modified by any other code.
*/
unsigned int nb_streams;
* A list of streams in the group. New entries are created with
* avformat_stream_group_add_stream().
*
* - demuxing: entries are created by libavformat on group creation.
* If AVFMTCTX_NOHEADER is set in ctx_flags, then new entries may also
* appear in av_read_frame().
* - muxing: entries are created by the user before avformat_write_header().
*
* Freed by libavformat in avformat_free_context().
*/
AVStream **streams;
* Stream group disposition - a combination of AV_DISPOSITION_* flags.
* This field currently applies to all defined AVStreamGroupParamsType.
*
* - demuxing: set by libavformat when creating the group or in
* avformat_find_stream_info().
* - muxing: may be set by the caller before avformat_write_header().
*/
int disposition;
} AVStreamGroup;
struct AVCodecParserContext *av_stream_get_parser(const AVStream *s);
#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;
unsigned int *stream_index;
unsigned int nb_stream_indexes;
AVDictionary *metadata;
int program_num;
int pmt_pid;
int pcr_pid;
int pmt_version;
* 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.
*****************************************************************
*/
int64_t start_time;
int64_t end_time;
int64_t pts_wrap_reference;
int pts_wrap_behavior;
} AVProgram;
#define AVFMTCTX_NOHEADER 0x0001
(streams are added dynamically) */
#define AVFMTCTX_UNSEEKABLE 0x0002
not seekable, and attempts to call the
seek function will fail. For some
network protocols (e.g. HLS), this can
change dynamically at runtime. */
typedef struct AVChapter {
int64_t id;
AVRational time_base;
int64_t start, end;
AVDictionary *metadata;
} AVChapter;
* Callback used by devices to communicate with application.
*/
typedef int (*av_format_control_message)(struct AVFormatContext *s, int type,
void *data, size_t data_size);
typedef int (*AVOpenCallback)(struct AVFormatContext *s, AVIOContext **pb, const char *url, int flags,
const AVIOInterruptCB *int_cb, AVDictionary **options);
* The duration of a video can be estimated through various ways, and this enum can be used
* to know how the duration was estimated.
*/
enum AVDurationEstimationMethod {
AVFMT_DURATION_FROM_PTS,
AVFMT_DURATION_FROM_STREAM,
AVFMT_DURATION_FROM_BITRATE
};
* 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.
*
* Fields can be accessed through AVOptions (av_opt*),
* the name string used matches the associated command line parameter name and
* can be found in libavformat/options_table.h.
* The AVOption/command line parameter names differ in some cases from the C
* structure field names for historic reasons or brevity.
*/
typedef struct AVFormatContext {
* A class for logging and @ref avoptions. Set by avformat_alloc_context().
* Exports (de)muxer private options if they exist.
*/
const AVClass *av_class;
* The input container format.
*
* Demuxing only, set by avformat_open_input().
*/
const struct AVInputFormat *iformat;
* The output container format.
*
* Muxing only, must be set by the caller before avformat_write_header().
*/
const 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.
*
* - 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
* I/O in some other way and this field will be NULL.
*/
AVIOContext *pb;
* 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().
*
* - 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().
*/
AVStream **streams;
* Number of elements in AVFormatContext.stream_groups.
*
* Set by avformat_stream_group_create(), must not be modified by any other code.
*/
unsigned int nb_stream_groups;
* A list of all stream groups in the file. New groups are created with
* avformat_stream_group_create(), and filled with avformat_stream_group_add_stream().
*
* - demuxing: groups may be created by libavformat in avformat_open_input().
* If AVFMTCTX_NOHEADER is set in ctx_flags, then new groups may also
* appear in av_read_frame().
* - muxing: groups may be created by the user before avformat_write_header().
*
* Freed by libavformat in avformat_free_context().
*/
AVStreamGroup **stream_groups;
* 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;
* input or output URL. Unlike the old filename field, this field has no
* length restriction.
*
* - demuxing: set by avformat_open_input(), initialized to an empty
* string if url parameter was NULL in avformat_open_input().
* - muxing: may be set by the caller before calling avformat_write_header()
* (or avformat_init_output() if that is called first) to a string
* which is freeable by av_free(). Set to an empty string if it
* was NULL in avformat_init_output().
*
* Freed by libavformat in avformat_free_context().
*/
char *url;
* 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;
* 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;
* 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.
*/
int64_t bit_rate;
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
#define AVFMT_FLAG_IGNIDX 0x0002
#define AVFMT_FLAG_NONBLOCK 0x0004
#define AVFMT_FLAG_IGNDTS 0x0008
#define AVFMT_FLAG_NOFILLIN 0x0010
#define AVFMT_FLAG_NOPARSE 0x0020
#define AVFMT_FLAG_NOBUFFER 0x0040
#define AVFMT_FLAG_CUSTOM_IO 0x0080
#define AVFMT_FLAG_DISCARD_CORRUPT 0x0100
#define AVFMT_FLAG_FLUSH_PACKETS 0x0200
* 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
#define AVFMT_FLAG_SORT_DTS 0x10000
#define AVFMT_FLAG_FAST_SEEK 0x80000
#if FF_API_LAVF_SHORTEST
#define AVFMT_FLAG_SHORTEST 0x100000
#endif
#define AVFMT_FLAG_AUTO_BSF 0x200000
* Maximum number of bytes read from input in order to determine stream
* properties. Used when reading the global header and in
* avformat_find_stream_info().
*
* Demuxing only, set by the caller before avformat_open_input().
*
* @note this is \e not used for determining the \ref AVInputFormat
* "input format"
* @see format_probesize
*/
int64_t probesize;
* 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().
* Can be set to 0 to let avformat choose using a heuristic.
*/
int64_t max_analyze_duration;
const uint8_t *key;
int keylen;
unsigned int nb_programs;
AVProgram **programs;
* Forced video codec_id.
* Demuxing: Set by user.
*/
enum AVCodecID video_codec_id;
* Forced audio codec_id.
* Demuxing: Set by user.
*/
enum AVCodecID audio_codec_id;
* Forced subtitle codec_id.
* Demuxing: Set by user.
*/
enum AVCodecID subtitle_codec_id;
* Forced Data codec_id.
* Demuxing: Set by user.
*/
enum AVCodecID data_codec_id;
* 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.
* - muxing: Set by the caller before avformat_write_header(). If set to
* either 0 or AV_NOPTS_VALUE, then the current wall-time will
* be used.
* - demuxing: Set by libavformat. AV_NOPTS_VALUE if unknown. Note that
* the value may become known after some number of frames
* have been received.
*/
int64_t start_time_realtime;
* 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.
* Demuxing only, set by the caller before avformat_open_input().
*/
int error_recognition;
* Custom interrupt callbacks for the I/O layer.
*
* 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.
*/
AVIOInterruptCB interrupt_callback;
* Flags to enable debugging.
*/
int debug;
#define FF_FDEBUG_TS 0x0001
* The maximum number of streams.
* - encoding: unused
* - decoding: set by user
*/
int max_streams;
* 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;
* 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;
* Maximum number of packets to read while waiting for the first timestamp.
* Decoding only.
*/
int max_ts_probe;
* 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
* - 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
* - decoding: unused
*/
int max_chunk_size;
* Maximum number of packets that can be probed
* - encoding: unused
* - decoding: set by user
*/
int max_probe_packets;
* Allow non-standard and experimental extension
* @see AVCodecContext.strict_std_compliance
*/
int strict_std_compliance;
* Flags indicating events happening on the file, a combination of
* AVFMT_EVENT_FLAG_*.
*
* - demuxing: may be set by the demuxer in avformat_open_input(),
* avformat_find_stream_info() and av_read_frame(). Flags must be cleared
* by the user once the event has been handled.
* - muxing: may be set by the user after avformat_write_header() to
* indicate a user-triggered event. The muxer will clear the flags for
* events it has handled in av_[interleaved]_write_frame().
*/
int event_flags;
* - demuxing: the demuxer read new metadata from the file and updated
* AVFormatContext.metadata accordingly
* - muxing: the user updated AVFormatContext.metadata and wishes the muxer to
* write it into the file
*/
#define AVFMT_EVENT_FLAG_METADATA_UPDATED 0x0001
* Avoid negative timestamps during muxing.
* Any value of the AVFMT_AVOID_NEG_TS_* constants.
* Note, this works better when using av_interleaved_write_frame().
* - muxing: Set by user
* - demuxing: unused
*/
int avoid_negative_ts;
#define AVFMT_AVOID_NEG_TS_AUTO -1
#define AVFMT_AVOID_NEG_TS_DISABLED 0
#define AVFMT_AVOID_NEG_TS_MAKE_NON_NEGATIVE 1
#define AVFMT_AVOID_NEG_TS_MAKE_ZERO 2
* 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
* - decoding: unused
*/
int audio_preload;
* forces the use of wallclock timestamps as pts/dts of packets
* This has undefined results in the presence of B frames.
* - encoding: unused
* - decoding: Set by user
*/
int use_wallclock_as_timestamps;
* Skip duration calcuation in estimate_timings_from_pts.
* - encoding: unused
* - decoding: set by user
*
* @see duration_probesize
*/
int skip_estimate_duration_from_pts;
* avio flags, used to force AVIO_FLAG_DIRECT.
* - encoding: unused
* - decoding: Set by user
*/
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.
* - encoding: unused
* - decoding: Read by user
*/
enum AVDurationEstimationMethod duration_estimation_method;
* Skip initial bytes when opening stream
* - encoding: unused
* - decoding: Set by user
*/
int64_t skip_initial_bytes;
* Correct single timestamp overflows
* - encoding: unused
* - decoding: Set by user
*/
unsigned int correct_ts_overflow;
* Force seeking to any (also non key) frames.
* - encoding: unused
* - decoding: Set by user
*/
int seek2any;
* Flush the I/O context after each packet.
* - encoding: Set by user
* - decoding: unused
*/
int flush_packets;
* format probing score.
* The maximal score is AVPROBE_SCORE_MAX, its set when the demuxer probes
* the format.
* - encoding: unused
* - decoding: set by avformat, read by user
*/
int probe_score;
* Maximum number of bytes read from input in order to identify the
* \ref AVInputFormat "input format". Only used when the format is not set
* explicitly by the caller.
*
* Demuxing only, set by the caller before avformat_open_input().
*
* @see probesize
*/
int format_probesize;
* ',' separated list of allowed decoders.
* If NULL then all are allowed
* - encoding: unused
* - decoding: set by user
*/
char *codec_whitelist;
* ',' separated list of allowed demuxers.
* If NULL then all are allowed
* - encoding: unused
* - decoding: set by user
*/
char *format_whitelist;
* ',' separated list of allowed protocols.
* - encoding: unused
* - decoding: set by user
*/
char *protocol_whitelist;
* ',' separated list of disallowed protocols.
* - encoding: unused
* - decoding: set by user
*/
char *protocol_blacklist;
* IO repositioned flag.
* This is set by avformat when the underlaying IO context read pointer
* is repositioned, for example when doing byte based seeking.
* Demuxers can use the flag to detect such changes.
*/
int io_repositioned;
* Forced video codec.
* This allows forcing a specific decoder, even when there are multiple with
* the same codec_id.
* Demuxing: Set by user
*/
const struct AVCodec *video_codec;
* Forced audio codec.
* This allows forcing a specific decoder, even when there are multiple with
* the same codec_id.
* Demuxing: Set by user
*/
const struct AVCodec *audio_codec;
* Forced subtitle codec.
* This allows forcing a specific decoder, even when there are multiple with
* the same codec_id.
* Demuxing: Set by user
*/
const struct AVCodec *subtitle_codec;
* Forced data codec.
* This allows forcing a specific decoder, even when there are multiple with
* the same codec_id.
* Demuxing: Set by user
*/
const struct AVCodec *data_codec;
* Number of bytes to be written as padding in a metadata header.
* Demuxing: Unused.
* Muxing: Set by user.
*/
int metadata_header_padding;
* User data.
* This is a place for some private data of the user.
*/
void *opaque;
* Callback used by devices to communicate with application.
*/
av_format_control_message control_message_cb;
* Output timestamp offset, in microseconds.
* Muxing: set by user
*/
int64_t output_ts_offset;
* dump format separator.
* can be ", " or "\n " or anything else
* - muxing: Set by user.
* - demuxing: Set by user.
*/
uint8_t *dump_separator;
* A callback for opening new IO streams.
*
* Whenever a muxer or a demuxer needs to open an IO stream (typically from
* avformat_open_input() for demuxers, but for certain formats can happen at
* other times as well), it will call this callback to obtain an IO context.
*
* @param s the format context
* @param pb on success, the newly opened IO context should be returned here
* @param url the url to open
* @param flags a combination of AVIO_FLAG_*
* @param options a dictionary of additional options, with the same
* semantics as in avio_open2()
* @return 0 on success, a negative AVERROR code on failure
*
* @note Certain muxers and demuxers do nesting, i.e. they open one or more
* additional internal format contexts. Thus the AVFormatContext pointer
* passed to this callback may be different from the one facing the caller.
* It will, however, have the same 'opaque' field.
*/
int (*io_open)(struct AVFormatContext *s, AVIOContext **pb, const char *url,
int flags, AVDictionary **options);
* A callback for closing the streams opened with AVFormatContext.io_open().
*
* Using this is preferred over io_close, because this can return an error.
* Therefore this callback is used instead of io_close by the generic
* libavformat code if io_close is NULL or the default.
*
* @param s the format context
* @param pb IO context to be closed and freed
* @return 0 on success, a negative AVERROR code on failure
*/
int (*io_close2)(struct AVFormatContext *s, AVIOContext *pb);
* Maximum number of bytes read from input in order to determine stream durations
* when using estimate_timings_from_pts in avformat_find_stream_info().
* Demuxing only, set by the caller before avformat_find_stream_info().
* Can be set to 0 to let avformat choose using a heuristic.
*
* @see skip_estimate_duration_from_pts
*/
int64_t duration_probesize;
} AVFormatContext;
* This function will cause global side data to be injected in the next packet
* of each stream as well as after any subsequent seek.
*
* @note global side data is always available in every AVStream's
* @ref AVCodecParameters.coded_side_data "codecpar side data" array, and
* in a @ref AVCodecContext.coded_side_data "decoder's side data" array if
* initialized with said stream's codecpar.
* @see av_packet_side_data_get()
*/
void av_format_inject_global_side_data(AVFormatContext *s);
#if FF_API_GET_DUR_ESTIMATE_METHOD
* Returns the method used to set ctx->duration.
*
* @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE.
* @deprecated duration_estimation_method is public and can be read directly.
*/
attribute_deprecated
enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx);
#endif
* @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);
* Do global initialization of network libraries. This is optional,
* and not recommended anymore.
*
* This functions only exists to work around thread-safety issues
* with older GnuTLS or OpenSSL libraries. If libavformat is linked
* to newer versions of those libraries, or if you do not use them,
* calling this function is unnecessary. Otherwise, you need to call
* this function before any other threads using them are started.
*
* This function will be deprecated once support for older GnuTLS and
* OpenSSL libraries is removed, and this function has no purpose
* anymore.
*/
int avformat_network_init(void);
* Undo the initialization done by avformat_network_init. Call it only
* once for each time you called avformat_network_init.
*/
int avformat_network_deinit(void);
* Iterate over all registered muxers.
*
* @param opaque a pointer where libavformat will store the iteration state. Must
* point to NULL to start the iteration.
*
* @return the next registered muxer or NULL when the iteration is
* finished
*/
const AVOutputFormat *av_muxer_iterate(void **opaque);
* Iterate over all registered demuxers.
*
* @param opaque a pointer where libavformat will store the iteration state.
* Must point to NULL to start the iteration.
*
* @return the next registered demuxer or NULL when the iteration is
* finished
*/
const AVInputFormat *av_demuxer_iterate(void **opaque);
* 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);
* Get the AVClass for AVStream. It can be used in combination with
* AV_OPT_SEARCH_FAKE_OBJ for examining options.
*
* @see av_opt_find().
*/
const AVClass *av_stream_get_class(void);
* Get the AVClass for AVStreamGroup. It can be used in combination with
* AV_OPT_SEARCH_FAKE_OBJ for examining options.
*
* @see av_opt_find().
*/
const AVClass *av_stream_group_get_class(void);
* @return a string identifying the stream group type, or NULL if unknown
*/
const char *avformat_stream_group_name(enum AVStreamGroupParamsType type);
* Add a new empty stream group to a media file.
*
* When demuxing, it may be 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, may be called by the user before avformat_write_header().
*
* User is required to call avformat_free_context() to clean up the allocation
* by avformat_stream_group_create().
*
* New streams can be added to the group with avformat_stream_group_add_stream().
*
* @param s media file handle
*
* @return newly created group or NULL on error.
* @see avformat_new_stream, avformat_stream_group_add_stream.
*/
AVStreamGroup *avformat_stream_group_create(AVFormatContext *s,
enum AVStreamGroupParamsType type,
AVDictionary **options);
* 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().
*
* User is required to call avformat_free_context() to clean up the allocation
* by avformat_new_stream().
*
* @param s media file handle
* @param c unused, does nothing
*
* @return newly created stream or NULL on error.
*/
AVStream *avformat_new_stream(AVFormatContext *s, const struct AVCodec *c);
* Add an already allocated stream to a stream group.
*
* When demuxing, it may be 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, may be called by the user before avformat_write_header() after
* having allocated a new group with avformat_stream_group_create() and stream with
* avformat_new_stream().
*
* User is required to call avformat_free_context() to clean up the allocation
* by avformat_stream_group_add_stream().
*
* @param stg stream group belonging to a media file.
* @param st stream in the media file to add to the group.
*
* @retval 0 success
* @retval AVERROR(EEXIST) the stream was already in the group
* @retval "another negative error code" legitimate errors
*
* @see avformat_new_stream, avformat_stream_group_create.
*/
int avformat_stream_group_add_stream(AVStreamGroup *stg, AVStream *st);
#if FF_API_AVSTREAM_SIDE_DATA
* Wrap an existing array as stream side data.
*
* @param st stream
* @param type side information type
* @param data the side data array. It must be allocated with the av_malloc()
* family of functions. The ownership of the data is transferred to
* st.
* @param size side information size
*
* @return zero on success, a negative AVERROR code on failure. On failure,
* the stream is unchanged and the data remains owned by the caller.
* @deprecated use av_packet_side_data_add() with the stream's
* @ref AVCodecParameters.coded_side_data "codecpar side data"
*/
attribute_deprecated
int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type,
uint8_t *data, size_t size);
* Allocate new information from stream.
*
* @param stream stream
* @param type desired side information type
* @param size side information size
*
* @return pointer to fresh allocated data or NULL otherwise
* @deprecated use av_packet_side_data_new() with the stream's
* @ref AVCodecParameters.coded_side_data "codecpar side data"
*/
attribute_deprecated
uint8_t *av_stream_new_side_data(AVStream *stream,
enum AVPacketSideDataType type, size_t size);
* Get side information from stream.
*
* @param stream stream
* @param type desired side information type
* @param size If supplied, *size will be set to the size of the side data
* or to zero if the desired side data is not present.
*
* @return pointer to data if present or NULL otherwise
* @deprecated use av_packet_side_data_get() with the stream's
* @ref AVCodecParameters.coded_side_data "codecpar side data"
*/
attribute_deprecated
uint8_t *av_stream_get_side_data(const AVStream *stream,
enum AVPacketSideDataType type, size_t *size);
#endif
AVProgram *av_new_program(AVFormatContext *s, int id);
* @}
*/
* 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 pointee 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, const AVOutputFormat *oformat,
const char *format_name, const char *filename);
* @addtogroup lavf_decoding
* @{
*/
* Find AVInputFormat based on the short name of the input format.
*/
const 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.
*/
const AVInputFormat *av_probe_input_format(const 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
* 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.
*/
const AVInputFormat *av_probe_input_format2(const 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.
*/
const AVInputFormat *av_probe_input_format3(const 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 url the url 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 the score in case of success, a negative value corresponding to an
* the maximal score is AVPROBE_SCORE_MAX
* AVERROR code otherwise
*/
int av_probe_input_buffer2(AVIOContext *pb, const AVInputFormat **fmt,
const char *url, void *logctx,
unsigned int offset, unsigned int max_probe_size);
* Like av_probe_input_buffer2() but returns 0 on success
*/
int av_probe_input_buffer(AVIOContext *pb, const AVInputFormat **fmt,
const char *url, 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 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
* function and written into ps.
* Note that a user-supplied AVFormatContext will be freed
* on failure.
* @param url URL 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 *url,
const AVInputFormat *fmt, AVDictionary **options);
* 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);
void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
* 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,
const struct AVCodec **decoder_ret,
int flags);
* 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.
*
* On success, the returned packet is reference-counted (pkt->buf is set) and
* valid indefinitely. The packet must be freed with av_packet_unref() 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
* 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. On error, pkt will be blank
* (as if it came from av_packet_alloc()).
*
* @note pkt will be initialized, so it may be uninitialized, but it must not
* contain data that needs to be freed.
*/
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.
* @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).
* If flags contain AVSEEK_FLAG_BACKWARD, it is ignored.
*
* @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
* @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.
*/
int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
* Discard all internally buffered data. This can be useful when dealing with
* discontinuities in the byte stream. Generally works only with formats that
* can resync. This includes headerless formats like MPEG-TS/TS but should also
* work with NUT, Ogg and in a limited way AVI for example.
*
* The set of streams, the detected duration, stream parameters and codecs do
* not change when calling this function. If you want a complete reset, it's
* better to open a new AVFormatContext.
*
* This does not flush the AVIOContext (s->pb). If necessary, call
* avio_flush(s->pb) before calling this function.
*
* @param s media file handle
* @return >=0 on success, error code otherwise
*/
int avformat_flush(AVFormatContext *s);
* 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);
* Close an opened input AVFormatContext. Free it and all its contents
* and set *s to NULL.
*/
void avformat_close_input(AVFormatContext **s);
* @}
*/
#define AVSEEK_FLAG_BACKWARD 1
#define AVSEEK_FLAG_BYTE 2
#define AVSEEK_FLAG_ANY 4
#define AVSEEK_FLAG_FRAME 8
* @addtogroup lavf_encoding
* @{
*/
#define AVSTREAM_INIT_IN_WRITE_HEADER 0
#define AVSTREAM_INIT_IN_INIT_OUTPUT 1
* 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 \ref AVFormatContext.oformat "oformat" field must be set
* to the desired output format;
* Its \ref AVFormatContext.pb "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.
*
* @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec had not already been
* fully initialized in avformat_init_output().
* @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec had already been fully
* initialized in avformat_init_output().
* @retval AVERROR A negative AVERROR on failure.
*
* @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output.
*/
av_warn_unused_result
int avformat_write_header(AVFormatContext *s, AVDictionary **options);
* Allocate the stream private data and initialize the codec, but do not write the header.
* May optionally be used before avformat_write_header() to initialize stream parameters
* before actually writing the header.
* If using this function, do not pass the same options to avformat_write_header().
*
* @param s Media file handle, must be allocated with
* avformat_alloc_context().
* Its \ref AVFormatContext.oformat "oformat" field must be set
* to the desired output format;
* Its \ref AVFormatContext.pb "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.
*
* @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec requires
* avformat_write_header to fully initialize.
* @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec has been fully
* initialized.
* @retval AVERROR Anegative AVERROR on failure.
*
* @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header.
*/
av_warn_unused_result
int avformat_init_output(AVFormatContext *s, AVDictionary **options);
* Write a packet to an output media file.
*
* 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 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).
* <br>
* 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.
* <br>
* 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".
* <br>
* The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
* must be set to correct values in the stream's timebase (unless the
* output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
* they can be set to AV_NOPTS_VALUE).
* The dts for subsequent packets passed to this function must be strictly
* increasing when compared in their respective timebases (unless the
* output format is flagged with the AVFMT_TS_NONSTRICT, then they
* merely have to be nondecreasing). @ref AVPacket.duration
* "duration") should also be set if known.
* @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.
*
* This function will buffer the packets internally as needed to make sure the
* packets in the output file are properly interleaved, usually ordered by
* increasing dts. Callers doing their own interleaving should call
* av_write_frame() instead of this function.
*
* Using this function instead of av_write_frame() can give muxers advance
* knowledge of future packets, improving e.g. the behaviour of the mp4
* muxer for VFR content in fragmenting mode.
*
* @param s media file handle
* @param pkt The packet containing the data to be written.
* <br>
* If the packet is reference-counted, this function will take
* ownership of this reference and unreference it later when it sees
* fit. If the packet is not reference-counted, libavformat will
* make a copy.
* The returned packet will be blank (as if returned from
* av_packet_alloc()), even on error.
* <br>
* This parameter can be NULL (at any time, not just at the end), to
* flush the interleaving queues.
* <br>
* 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".
* <br>
* The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts")
* must be set to correct values in the stream's timebase (unless the
* output format is flagged with the AVFMT_NOTIMESTAMPS flag, then
* they can be set to AV_NOPTS_VALUE).
* The dts for subsequent packets in one stream must be strictly
* increasing (unless the output format is flagged with the
* AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing).
* @ref AVPacket.duration "duration" should also be set if known.
*
* @return 0 on success, a negative AVERROR on error.
*
* @see av_write_frame(), AVFormatContext.max_interleave_delta
*/
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
* Write an uncoded frame to an output media file.
*
* The frame must be correctly interleaved according to the container
* specification; if not, av_interleaved_write_uncoded_frame() must be used.
*
* See av_interleaved_write_uncoded_frame() for details.
*/
int av_write_uncoded_frame(AVFormatContext *s, int stream_index,
struct AVFrame *frame);
* Write an uncoded frame to an output media file.
*
* If the muxer supports it, this function makes it possible to write an AVFrame
* structure directly, without encoding it into a packet.
* It is mostly useful for devices and similar special muxers that use raw
* video or PCM data and will not serialize it into a byte stream.
*
* To test whether it is possible to use it with a given muxer and stream,
* use av_write_uncoded_frame_query().
*
* The caller gives up ownership of the frame and must not access it
* afterwards.
*
* @return >=0 for success, a negative code on error
*/
int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index,
struct AVFrame *frame);
* Test whether a muxer supports uncoded frame.
*
* @return >=0 if an uncoded frame can be written to that muxer and stream,
* <0 if not
*/
int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index);
* Write the stream trailer to an output media file and free the
* file private data.
*
* 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
*/
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
*/
const 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 AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name,
const char *filename, const char *mime_type,
enum AVMediaType type);
struct KeyFrameNode
{
int pos;
struct KeyFrameNode *next;
};
* Get the frame position for every key frame.
*
* @param st input stream to extract the position for every key frame
* @param key_frame_pos_list output list which carry the frame position for every key frame
*/
int av_get_key_frame_pos_from_stream(const AVStream *st, struct KeyFrameNode **key_frame_pos_list);
* Destroy the list which is created by av_get_key_frame_pos_from_stream function.
*
* This function is useful after doing av_get_key_frame_pos_from_stream to release resource.
*
* @param key_frame_pos_list input list which carry the frame position for every key frame
*/
void av_destory_key_frame_pos_list(struct KeyFrameNode *key_frame_pos_list);
* 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[out] dts DTS of the last packet output for the stream, in stream
* time_base units
* @param[out] wall absolute time when that packet whas output,
* in microsecond
* @retval 0 Success
* @retval AVERROR(ENOSYS) 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
* @{
*
* Miscellaneous 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, const 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, const 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, const AVPacket *pkt, int dump_payload, const 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, const AVPacket *pkt, int dump_payload,
const AVStream *st);
* 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 AVCodecID 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
* @param id codec ID to match to a codec tag
*/
unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
* Get the codec tag for the given codec id.
*
* @param tags list of supported codec_id - codec_tag pairs, as stored
* in AVInputFormat.codec_tag and AVOutputFormat.codec_tag
* @param id codec id that should be searched for in the list
* @param tag A pointer to the found tag
* @return 0 if id was not found in tags, > 0 if it was found
*/
int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id,
unsigned int *tag);
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 >=
* 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);
* Get the index entry count for the given AVStream.
*
* @param st stream
* @return the number of index entries in the stream
*/
int avformat_index_get_entries_count(const AVStream *st);
* Get the AVIndexEntry corresponding to the given index.
*
* @param st Stream containing the requested AVIndexEntry.
* @param idx The desired index.
* @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
*
* @note The pointer returned by this function is only guaranteed to be valid
* until any function that takes the stream or the parent AVFormatContext
* as input argument is called.
*/
const AVIndexEntry *avformat_index_get_entry(AVStream *st, int idx);
* Get the AVIndexEntry corresponding to the given timestamp.
*
* @param st Stream containing the requested AVIndexEntry.
* @param wanted_timestamp Timestamp to retrieve the index entry for.
* @param flags If AVSEEK_FLAG_BACKWARD then the returned entry 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 A pointer to the requested AVIndexEntry if it exists, NULL otherwise.
*
* @note The pointer returned by this function is only guaranteed to be valid
* until any function that takes the stream or the parent AVFormatContext
* as input argument is called.
*/
const AVIndexEntry *avformat_index_get_entry_from_timestamp(AVStream *st,
int64_t wanted_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);
* 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 index of the stream to dump information about
* @param url the URL to print, such as source or destination file
* @param is_output Select whether the specified context is an input(0) or output(1)
*/
void av_dump_format(AVFormatContext *ic,
int index,
const char *url,
int is_output);
#define AV_FRAME_FILENAME_FLAGS_MULTIPLE 1
* 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
* @param flags AV_FRAME_FILENAME_FLAGS_*
* @return 0 if OK, -1 on format error
*/
int av_get_frame_filename2(char *buf, int buf_size,
const char *path, int number, int flags);
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.
*
* 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,
* 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 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);
* 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(const AVOutputFormat *ofmt, enum AVCodecID codec_id,
int std_compliance);
* @defgroup riff_fourcc RIFF FourCCs
* @{
* 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 AVCodecID id = av_codec_get_id(table, tag);
* @endcode
*/
* @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 AVCodecID.
*/
const struct AVCodecTag *avformat_get_riff_audio_tags(void);
* @return the table mapping MOV FourCCs for video to libavcodec AVCodecID.
*/
const struct AVCodecTag *avformat_get_mov_video_tags(void);
* @return the table mapping MOV FourCCs for audio to AVCodecID.
*/
const struct AVCodecTag *avformat_get_mov_audio_tags(void);
* @}
*/
* Guess 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,
struct AVFrame *frame);
* Guess the frame rate, based on both the container and codec information.
*
* @param ctx the format context which the stream is part of
* @param stream the stream which the frame is part of
* @param frame the frame for which the frame rate should be determined, may be NULL
* @return the guessed (valid) frame rate, 0/1 if no idea
*/
AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream,
struct AVFrame *frame);
* Check if the stream st contained in s is matched by the stream specifier
* spec.
*
* See the "stream specifiers" chapter in the documentation for the syntax
* of spec.
*
* @return >0 if st is matched by spec;
* 0 if st is not matched by spec;
* AVERROR code if spec is invalid
*
* @note A stream specifier can match several streams in the format.
*/
int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
const char *spec);
int avformat_queue_attached_pictures(AVFormatContext *s);
#if FF_API_INTERNAL_TIMING
enum AVTimebaseSource {
AVFMT_TBCF_AUTO = -1,
AVFMT_TBCF_DECODER,
AVFMT_TBCF_DEMUXER,
#if FF_API_R_FRAME_RATE
AVFMT_TBCF_R_FRAMERATE,
#endif
};
* @deprecated do not call this function
*/
attribute_deprecated
int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt,
AVStream *ost, const AVStream *ist,
enum AVTimebaseSource copy_tb);
* @deprecated do not call this function
*/
attribute_deprecated
AVRational av_stream_get_codec_timebase(const AVStream *st);
#endif
* @}
*/
#endif
