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1721 lines
63 KiB
C
1721 lines
63 KiB
C
/*
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* copyright (c) 2001 Fabrice Bellard
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef AVFORMAT_AVFORMAT_H
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#define AVFORMAT_AVFORMAT_H
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/**
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* @file
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* @ingroup libavf
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* Main libavformat public API header
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*/
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/**
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* @defgroup libavf I/O and Muxing/Demuxing Library
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* @{
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*
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* Libavformat (lavf) is a library for dealing with various media container
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* formats. Its main two purposes are demuxing - i.e. splitting a media file
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* into component streams, and the reverse process of muxing - writing supplied
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* data in a specified container format. It also has an @ref lavf_io
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* "I/O module" which supports a number of protocols for accessing the data (e.g.
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* file, tcp, http and others). Before using lavf, you need to call
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* av_register_all() to register all compiled muxers, demuxers and protocols.
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* Unless you are absolutely sure you won't use libavformat's network
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* capabilities, you should also call avformat_network_init().
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*
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* A supported input format is described by an AVInputFormat struct, conversely
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* an output format is described by AVOutputFormat. You can iterate over all
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* registered input/output formats using the av_iformat_next() /
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* av_oformat_next() functions. The protocols layer is not part of the public
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* API, so you can only get the names of supported protocols with the
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* avio_enum_protocols() function.
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*
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* Main lavf structure used for both muxing and demuxing is AVFormatContext,
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* which exports all information about the file being read or written. As with
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* most Libav structures, its size is not part of public ABI, so it cannot be
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* allocated on stack or directly with av_malloc(). To create an
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* AVFormatContext, use avformat_alloc_context() (some functions, like
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* avformat_open_input() might do that for you).
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*
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* Most importantly an AVFormatContext contains:
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* @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat
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* "output" format. It is either autodetected or set by user for input;
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* always set by user for output.
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* @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all
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* elementary streams stored in the file. AVStreams are typically referred to
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* using their index in this array.
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* @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or
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* set by user for input, always set by user for output (unless you are dealing
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* with an AVFMT_NOFILE format).
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*
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* @section lavf_options Passing options to (de)muxers
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* Lavf allows to configure muxers and demuxers using the @ref avoptions
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* mechanism. Generic (format-independent) libavformat options are provided by
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* AVFormatContext, they can be examined from a user program by calling
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* av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass
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* from avformat_get_class()). Private (format-specific) options are provided by
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* AVFormatContext.priv_data if and only if AVInputFormat.priv_class /
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* AVOutputFormat.priv_class of the corresponding format struct is non-NULL.
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* Further options may be provided by the @ref AVFormatContext.pb "I/O context",
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* if its AVClass is non-NULL, and the protocols layer. See the discussion on
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* nesting in @ref avoptions documentation to learn how to access those.
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*
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* @defgroup lavf_decoding Demuxing
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* @{
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* Demuxers read a media file and split it into chunks of data (@em packets). A
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* @ref AVPacket "packet" contains one or more encoded frames which belongs to a
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* single elementary stream. In the lavf API this process is represented by the
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* avformat_open_input() function for opening a file, av_read_frame() for
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* reading a single packet and finally avformat_close_input(), which does the
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* cleanup.
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*
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* @section lavf_decoding_open Opening a media file
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* The minimum information required to open a file is its URL or filename, which
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* is passed to avformat_open_input(), as in the following code:
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* @code
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* const char *url = "in.mp3";
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* AVFormatContext *s = NULL;
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* int ret = avformat_open_input(&s, url, NULL, NULL);
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* if (ret < 0)
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* abort();
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* @endcode
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* The above code attempts to allocate an AVFormatContext, open the
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* specified file (autodetecting the format) and read the header, exporting the
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* information stored there into s. Some formats do not have a header or do not
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* store enough information there, so it is recommended that you call the
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* avformat_find_stream_info() function which tries to read and decode a few
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* frames to find missing information.
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*
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* In some cases you might want to preallocate an AVFormatContext yourself with
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* avformat_alloc_context() and do some tweaking on it before passing it to
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* avformat_open_input(). One such case is when you want to use custom functions
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* for reading input data instead of lavf internal I/O layer.
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* To do that, create your own AVIOContext with avio_alloc_context(), passing
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* your reading callbacks to it. Then set the @em pb field of your
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* AVFormatContext to newly created AVIOContext.
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*
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* Since the format of the opened file is in general not known until after
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* avformat_open_input() has returned, it is not possible to set demuxer private
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* options on a preallocated context. Instead, the options should be passed to
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* avformat_open_input() wrapped in an AVDictionary:
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* @code
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* AVDictionary *options = NULL;
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* av_dict_set(&options, "video_size", "640x480", 0);
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* av_dict_set(&options, "pixel_format", "rgb24", 0);
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*
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* if (avformat_open_input(&s, url, NULL, &options) < 0)
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* abort();
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* av_dict_free(&options);
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* @endcode
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* This code passes the private options 'video_size' and 'pixel_format' to the
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* demuxer. They would be necessary for e.g. the rawvideo demuxer, since it
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* cannot know how to interpret raw video data otherwise. If the format turns
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* out to be something different than raw video, those options will not be
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* recognized by the demuxer and therefore will not be applied. Such unrecognized
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* options are then returned in the options dictionary (recognized options are
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* consumed). The calling program can handle such unrecognized options as it
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* wishes, e.g.
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* @code
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* AVDictionaryEntry *e;
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* if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
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* fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key);
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* abort();
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* }
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* @endcode
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*
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* After you have finished reading the file, you must close it with
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* avformat_close_input(). It will free everything associated with the file.
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*
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* @section lavf_decoding_read Reading from an opened file
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* Reading data from an opened AVFormatContext is done by repeatedly calling
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* av_read_frame() on it. Each call, if successful, will return an AVPacket
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* containing encoded data for one AVStream, identified by
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* AVPacket.stream_index. This packet may be passed straight into the libavcodec
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* decoding functions avcodec_decode_video2(), avcodec_decode_audio4() or
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* avcodec_decode_subtitle2() if the caller wishes to decode the data.
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*
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* AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be
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* set if known. They may also be unset (i.e. AV_NOPTS_VALUE for
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* pts/dts, 0 for duration) if the stream does not provide them. The timing
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* information will be in AVStream.time_base units, i.e. it has to be
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* multiplied by the timebase to convert them to seconds.
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*
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* If AVPacket.buf is set on the returned packet, then the packet is
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* allocated dynamically and the user may keep it indefinitely.
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* Otherwise, if AVPacket.buf is NULL, the packet data is backed by a
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* static storage somewhere inside the demuxer and the packet is only valid
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* until the next av_read_frame() call or closing the file. If the caller
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* requires a longer lifetime, av_dup_packet() will make an av_malloc()ed copy
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* of it.
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* In both cases, the packet must be freed with av_free_packet() when it is no
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* longer needed.
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*
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* @section lavf_decoding_seek Seeking
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* @}
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*
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* @defgroup lavf_encoding Muxing
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* @{
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* @}
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*
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* @defgroup lavf_io I/O Read/Write
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* @{
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* @}
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*
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* @defgroup lavf_codec Demuxers
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* @{
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* @defgroup lavf_codec_native Native Demuxers
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* @{
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* @}
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* @defgroup lavf_codec_wrappers External library wrappers
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* @{
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* @}
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* @}
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* @defgroup lavf_protos I/O Protocols
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* @{
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* @}
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* @defgroup lavf_internal Internal
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* @{
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* @}
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* @}
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*
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*/
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#include <time.h>
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#include <stdio.h> /* FILE */
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#include "libavcodec/avcodec.h"
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#include "libavutil/dict.h"
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#include "libavutil/log.h"
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#include "avio.h"
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#include "libavformat/version.h"
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#if FF_API_AV_GETTIME
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#include "libavutil/time.h"
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#endif
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struct AVFormatContext;
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/**
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* @defgroup metadata_api Public Metadata API
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* @{
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* @ingroup libavf
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* The metadata API allows libavformat to export metadata tags to a client
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* application when demuxing. Conversely it allows a client application to
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* set metadata when muxing.
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*
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* Metadata is exported or set as pairs of key/value strings in the 'metadata'
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* fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs
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* using the @ref lavu_dict "AVDictionary" API. Like all strings in Libav,
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* metadata is assumed to be UTF-8 encoded Unicode. Note that metadata
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* exported by demuxers isn't checked to be valid UTF-8 in most cases.
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*
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* Important concepts to keep in mind:
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* - Keys are unique; there can never be 2 tags with the same key. This is
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* also meant semantically, i.e., a demuxer should not knowingly produce
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* several keys that are literally different but semantically identical.
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* E.g., key=Author5, key=Author6. In this example, all authors must be
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* placed in the same tag.
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* - Metadata is flat, not hierarchical; there are no subtags. If you
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* want to store, e.g., the email address of the child of producer Alice
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* and actor Bob, that could have key=alice_and_bobs_childs_email_address.
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* - Several modifiers can be applied to the tag name. This is done by
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* appending a dash character ('-') and the modifier name in the order
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* they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng.
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* - language -- a tag whose value is localized for a particular language
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* is appended with the ISO 639-2/B 3-letter language code.
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* For example: Author-ger=Michael, Author-eng=Mike
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* The original/default language is in the unqualified "Author" tag.
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* A demuxer should set a default if it sets any translated tag.
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* - sorting -- a modified version of a tag that should be used for
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* sorting will have '-sort' appended. E.g. artist="The Beatles",
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* artist-sort="Beatles, The".
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*
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* - Demuxers attempt to export metadata in a generic format, however tags
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* with no generic equivalents are left as they are stored in the container.
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* Follows a list of generic tag names:
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*
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@verbatim
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album -- name of the set this work belongs to
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album_artist -- main creator of the set/album, if different from artist.
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e.g. "Various Artists" for compilation albums.
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artist -- main creator of the work
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comment -- any additional description of the file.
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composer -- who composed the work, if different from artist.
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copyright -- name of copyright holder.
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creation_time-- date when the file was created, preferably in ISO 8601.
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date -- date when the work was created, preferably in ISO 8601.
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disc -- number of a subset, e.g. disc in a multi-disc collection.
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encoder -- name/settings of the software/hardware that produced the file.
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encoded_by -- person/group who created the file.
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filename -- original name of the file.
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genre -- <self-evident>.
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language -- main language in which the work is performed, preferably
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in ISO 639-2 format. Multiple languages can be specified by
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separating them with commas.
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performer -- artist who performed the work, if different from artist.
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E.g for "Also sprach Zarathustra", artist would be "Richard
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Strauss" and performer "London Philharmonic Orchestra".
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publisher -- name of the label/publisher.
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service_name -- name of the service in broadcasting (channel name).
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service_provider -- name of the service provider in broadcasting.
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title -- name of the work.
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track -- number of this work in the set, can be in form current/total.
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variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of
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@endverbatim
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*
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* Look in the examples section for an application example how to use the Metadata API.
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*
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* @}
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*/
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/* packet functions */
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/**
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* Allocate and read the payload of a packet and initialize its
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* fields with default values.
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*
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* @param pkt packet
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* @param size desired payload size
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* @return >0 (read size) if OK, AVERROR_xxx otherwise
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*/
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int av_get_packet(AVIOContext *s, AVPacket *pkt, int size);
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/**
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* Read data and append it to the current content of the AVPacket.
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* If pkt->size is 0 this is identical to av_get_packet.
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* Note that this uses av_grow_packet and thus involves a realloc
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* which is inefficient. Thus this function should only be used
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* when there is no reasonable way to know (an upper bound of)
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* the final size.
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*
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* @param pkt packet
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* @param size amount of data to read
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* @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data
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* will not be lost even if an error occurs.
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*/
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int av_append_packet(AVIOContext *s, AVPacket *pkt, int size);
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/*************************************************/
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/* fractional numbers for exact pts handling */
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/**
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* The exact value of the fractional number is: 'val + num / den'.
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* num is assumed to be 0 <= num < den.
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*/
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typedef struct AVFrac {
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int64_t val, num, den;
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} AVFrac;
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/*************************************************/
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/* input/output formats */
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struct AVCodecTag;
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/**
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* This structure contains the data a format has to probe a file.
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*/
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typedef struct AVProbeData {
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const char *filename;
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unsigned char *buf; /**< Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero. */
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int buf_size; /**< Size of buf except extra allocated bytes */
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} AVProbeData;
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#define AVPROBE_SCORE_MAX 100 ///< maximum score, half of that is used for file-extension-based detection
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#define AVPROBE_PADDING_SIZE 32 ///< extra allocated bytes at the end of the probe buffer
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/// Demuxer will use avio_open, no opened file should be provided by the caller.
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#define AVFMT_NOFILE 0x0001
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#define AVFMT_NEEDNUMBER 0x0002 /**< Needs '%d' in filename. */
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#define AVFMT_SHOW_IDS 0x0008 /**< Show format stream IDs numbers. */
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#define AVFMT_RAWPICTURE 0x0020 /**< Format wants AVPicture structure for
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raw picture data. */
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#define AVFMT_GLOBALHEADER 0x0040 /**< Format wants global header. */
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#define AVFMT_NOTIMESTAMPS 0x0080 /**< Format does not need / have any timestamps. */
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#define AVFMT_GENERIC_INDEX 0x0100 /**< Use generic index building code. */
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#define AVFMT_TS_DISCONT 0x0200 /**< Format allows timestamp discontinuities. Note, muxers always require valid (monotone) timestamps */
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#define AVFMT_VARIABLE_FPS 0x0400 /**< Format allows variable fps. */
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#define AVFMT_NODIMENSIONS 0x0800 /**< Format does not need width/height */
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#define AVFMT_NOSTREAMS 0x1000 /**< Format does not require any streams */
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#define AVFMT_NOBINSEARCH 0x2000 /**< Format does not allow to fallback to binary search via read_timestamp */
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#define AVFMT_NOGENSEARCH 0x4000 /**< Format does not allow to fallback to generic search */
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#define AVFMT_NO_BYTE_SEEK 0x8000 /**< Format does not allow seeking by bytes */
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#define AVFMT_ALLOW_FLUSH 0x10000 /**< Format allows flushing. If not set, the muxer will not receive a NULL packet in the write_packet function. */
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#define AVFMT_TS_NONSTRICT 0x20000 /**< Format does not require strictly
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increasing timestamps, but they must
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still be monotonic */
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/**
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* @addtogroup lavf_encoding
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* @{
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*/
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typedef struct AVOutputFormat {
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const char *name;
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/**
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* Descriptive name for the format, meant to be more human-readable
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* than name. You should use the NULL_IF_CONFIG_SMALL() macro
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* to define it.
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*/
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const char *long_name;
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const char *mime_type;
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const char *extensions; /**< comma-separated filename extensions */
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/* output support */
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enum AVCodecID audio_codec; /**< default audio codec */
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enum AVCodecID video_codec; /**< default video codec */
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enum AVCodecID subtitle_codec; /**< default subtitle codec */
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/**
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* can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_RAWPICTURE,
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* AVFMT_GLOBALHEADER, AVFMT_NOTIMESTAMPS, AVFMT_VARIABLE_FPS,
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* AVFMT_NODIMENSIONS, AVFMT_NOSTREAMS, AVFMT_ALLOW_FLUSH,
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* AVFMT_TS_NONSTRICT
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*/
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int flags;
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/**
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* List of supported codec_id-codec_tag pairs, ordered by "better
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* choice first". The arrays are all terminated by AV_CODEC_ID_NONE.
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*/
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const struct AVCodecTag * const *codec_tag;
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const AVClass *priv_class; ///< AVClass for the private context
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/*****************************************************************
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* No fields below this line are part of the public API. They
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* may not be used outside of libavformat and can be changed and
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* removed at will.
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* New public fields should be added right above.
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*****************************************************************
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*/
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struct AVOutputFormat *next;
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/**
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* size of private data so that it can be allocated in the wrapper
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*/
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int priv_data_size;
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int (*write_header)(struct AVFormatContext *);
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/**
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* Write a packet. If AVFMT_ALLOW_FLUSH is set in flags,
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* pkt can be NULL in order to flush data buffered in the muxer.
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* When flushing, return 0 if there still is more data to flush,
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* or 1 if everything was flushed and there is no more buffered
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* data.
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*/
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int (*write_packet)(struct AVFormatContext *, AVPacket *pkt);
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int (*write_trailer)(struct AVFormatContext *);
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/**
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* Currently only used to set pixel format if not YUV420P.
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*/
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int (*interleave_packet)(struct AVFormatContext *, AVPacket *out,
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AVPacket *in, int flush);
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/**
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|
* Test if the given codec can be stored in this container.
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*
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* @return 1 if the codec is supported, 0 if it is not.
|
|
* A negative number if unknown.
|
|
*/
|
|
int (*query_codec)(enum AVCodecID id, int std_compliance);
|
|
} AVOutputFormat;
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
/**
|
|
* @addtogroup lavf_decoding
|
|
* @{
|
|
*/
|
|
typedef struct AVInputFormat {
|
|
/**
|
|
* A comma separated list of short names for the format. New names
|
|
* may be appended with a minor bump.
|
|
*/
|
|
const char *name;
|
|
|
|
/**
|
|
* Descriptive name for the format, meant to be more human-readable
|
|
* than name. You should use the NULL_IF_CONFIG_SMALL() macro
|
|
* to define it.
|
|
*/
|
|
const char *long_name;
|
|
|
|
/**
|
|
* Can use flags: AVFMT_NOFILE, AVFMT_NEEDNUMBER, AVFMT_SHOW_IDS,
|
|
* AVFMT_GENERIC_INDEX, AVFMT_TS_DISCONT, AVFMT_NOBINSEARCH,
|
|
* AVFMT_NOGENSEARCH, AVFMT_NO_BYTE_SEEK.
|
|
*/
|
|
int flags;
|
|
|
|
/**
|
|
* If extensions are defined, then no probe is done. You should
|
|
* usually not use extension format guessing because it is not
|
|
* reliable enough
|
|
*/
|
|
const char *extensions;
|
|
|
|
const struct AVCodecTag * const *codec_tag;
|
|
|
|
const AVClass *priv_class; ///< AVClass for the private context
|
|
|
|
/*****************************************************************
|
|
* No fields below this line are part of the public API. They
|
|
* may not be used outside of libavformat and can be changed and
|
|
* removed at will.
|
|
* New public fields should be added right above.
|
|
*****************************************************************
|
|
*/
|
|
struct AVInputFormat *next;
|
|
|
|
/**
|
|
* Raw demuxers store their codec ID here.
|
|
*/
|
|
int raw_codec_id;
|
|
|
|
/**
|
|
* Size of private data so that it can be allocated in the wrapper.
|
|
*/
|
|
int priv_data_size;
|
|
|
|
/**
|
|
* Tell if a given file has a chance of being parsed as this format.
|
|
* The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
|
|
* big so you do not have to check for that unless you need more.
|
|
*/
|
|
int (*read_probe)(AVProbeData *);
|
|
|
|
/**
|
|
* Read the format header and initialize the AVFormatContext
|
|
* structure. Return 0 if OK. Only used in raw format right
|
|
* now. 'avformat_new_stream' should be called to create new streams.
|
|
*/
|
|
int (*read_header)(struct AVFormatContext *);
|
|
|
|
/**
|
|
* Read one packet and put it in 'pkt'. pts and flags are also
|
|
* set. 'avformat_new_stream' can be called only if the flag
|
|
* AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
|
|
* background thread).
|
|
* @return 0 on success, < 0 on error.
|
|
* When returning an error, pkt must not have been allocated
|
|
* or must be freed before returning
|
|
*/
|
|
int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
|
|
|
|
/**
|
|
* Close the stream. The AVFormatContext and AVStreams are not
|
|
* freed by this function
|
|
*/
|
|
int (*read_close)(struct AVFormatContext *);
|
|
|
|
/**
|
|
* Seek to a given timestamp relative to the frames in
|
|
* stream component stream_index.
|
|
* @param stream_index Must not be -1.
|
|
* @param flags Selects which direction should be preferred if no exact
|
|
* match is available.
|
|
* @return >= 0 on success (but not necessarily the new offset)
|
|
*/
|
|
int (*read_seek)(struct AVFormatContext *,
|
|
int stream_index, int64_t timestamp, int flags);
|
|
|
|
/**
|
|
* Get the next timestamp in stream[stream_index].time_base units.
|
|
* @return the timestamp or AV_NOPTS_VALUE if an error occurred
|
|
*/
|
|
int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
|
|
int64_t *pos, int64_t pos_limit);
|
|
|
|
/**
|
|
* Start/resume playing - only meaningful if using a network-based format
|
|
* (RTSP).
|
|
*/
|
|
int (*read_play)(struct AVFormatContext *);
|
|
|
|
/**
|
|
* Pause playing - only meaningful if using a network-based format
|
|
* (RTSP).
|
|
*/
|
|
int (*read_pause)(struct AVFormatContext *);
|
|
|
|
/**
|
|
* Seek to timestamp ts.
|
|
* Seeking will be done so that the point from which all active streams
|
|
* can be presented successfully will be closest to ts and within min/max_ts.
|
|
* Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
|
|
*/
|
|
int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
|
|
} AVInputFormat;
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
enum AVStreamParseType {
|
|
AVSTREAM_PARSE_NONE,
|
|
AVSTREAM_PARSE_FULL, /**< full parsing and repack */
|
|
AVSTREAM_PARSE_HEADERS, /**< Only parse headers, do not repack. */
|
|
AVSTREAM_PARSE_TIMESTAMPS, /**< full parsing and interpolation of timestamps for frames not starting on a packet boundary */
|
|
AVSTREAM_PARSE_FULL_ONCE, /**< full parsing and repack of the first frame only, only implemented for H.264 currently */
|
|
};
|
|
|
|
typedef struct AVIndexEntry {
|
|
int64_t pos;
|
|
int64_t timestamp;
|
|
#define AVINDEX_KEYFRAME 0x0001
|
|
int flags:2;
|
|
int size:30; //Yeah, trying to keep the size of this small to reduce memory requirements (it is 24 vs. 32 bytes due to possible 8-byte alignment).
|
|
int min_distance; /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
|
|
} AVIndexEntry;
|
|
|
|
#define AV_DISPOSITION_DEFAULT 0x0001
|
|
#define AV_DISPOSITION_DUB 0x0002
|
|
#define AV_DISPOSITION_ORIGINAL 0x0004
|
|
#define AV_DISPOSITION_COMMENT 0x0008
|
|
#define AV_DISPOSITION_LYRICS 0x0010
|
|
#define AV_DISPOSITION_KARAOKE 0x0020
|
|
|
|
/**
|
|
* Track should be used during playback by default.
|
|
* Useful for subtitle track that should be displayed
|
|
* even when user did not explicitly ask for subtitles.
|
|
*/
|
|
#define AV_DISPOSITION_FORCED 0x0040
|
|
#define AV_DISPOSITION_HEARING_IMPAIRED 0x0080 /**< stream for hearing impaired audiences */
|
|
#define AV_DISPOSITION_VISUAL_IMPAIRED 0x0100 /**< stream for visual impaired audiences */
|
|
#define AV_DISPOSITION_CLEAN_EFFECTS 0x0200 /**< stream without voice */
|
|
/**
|
|
* The stream is stored in the file as an attached picture/"cover art" (e.g.
|
|
* APIC frame in ID3v2). The single packet associated with it will be returned
|
|
* among the first few packets read from the file unless seeking takes place.
|
|
* It can also be accessed at any time in AVStream.attached_pic.
|
|
*/
|
|
#define AV_DISPOSITION_ATTACHED_PIC 0x0400
|
|
|
|
/**
|
|
* Stream structure.
|
|
* New fields can be added to the end with minor version bumps.
|
|
* Removal, reordering and changes to existing fields require a major
|
|
* version bump.
|
|
* sizeof(AVStream) must not be used outside libav*.
|
|
*/
|
|
typedef struct AVStream {
|
|
int index; /**< stream index in AVFormatContext */
|
|
/**
|
|
* Format-specific stream ID.
|
|
* decoding: set by libavformat
|
|
* encoding: set by the user, replaced by libavformat if left unset
|
|
*/
|
|
int id;
|
|
/**
|
|
* Codec context associated with this stream. Allocated and freed by
|
|
* libavformat.
|
|
*
|
|
* - decoding: The demuxer exports codec information stored in the headers
|
|
* here.
|
|
* - encoding: The user sets codec information, the muxer writes it to the
|
|
* output. Mandatory fields as specified in AVCodecContext
|
|
* documentation must be set even if this AVCodecContext is
|
|
* not actually used for encoding.
|
|
*/
|
|
AVCodecContext *codec;
|
|
#if FF_API_R_FRAME_RATE
|
|
/**
|
|
* 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;
|
|
#endif
|
|
void *priv_data;
|
|
|
|
/**
|
|
* encoding: pts generation when outputting stream
|
|
*/
|
|
struct AVFrac pts;
|
|
|
|
/**
|
|
* This is the fundamental unit of time (in seconds) in terms
|
|
* of which frame timestamps are represented.
|
|
*
|
|
* decoding: set by libavformat
|
|
* encoding: set by libavformat in avformat_write_header. The muxer may use the
|
|
* user-provided value of @ref AVCodecContext.time_base "codec->time_base"
|
|
* as a hint.
|
|
*/
|
|
AVRational time_base;
|
|
|
|
/**
|
|
* Decoding: pts of the first frame of the stream, in 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).
|
|
*/
|
|
int64_t start_time;
|
|
|
|
/**
|
|
* Decoding: duration of the stream, in stream time base.
|
|
* If a source file does not specify a duration, but does specify
|
|
* a bitrate, this value will be estimated from bitrate and file size.
|
|
*/
|
|
int64_t duration;
|
|
|
|
int64_t nb_frames; ///< number of frames in this stream if known or 0
|
|
|
|
int disposition; /**< AV_DISPOSITION_* bit field */
|
|
|
|
enum AVDiscard discard; ///< Selects which packets can be discarded at will and do not need to be demuxed.
|
|
|
|
/**
|
|
* sample aspect ratio (0 if unknown)
|
|
* - encoding: Set by user.
|
|
* - decoding: Set by libavformat.
|
|
*/
|
|
AVRational sample_aspect_ratio;
|
|
|
|
AVDictionary *metadata;
|
|
|
|
/**
|
|
* Average framerate
|
|
*/
|
|
AVRational avg_frame_rate;
|
|
|
|
/**
|
|
* For streams with AV_DISPOSITION_ATTACHED_PIC disposition, this packet
|
|
* will contain the attached picture.
|
|
*
|
|
* decoding: set by libavformat, must not be modified by the caller.
|
|
* encoding: unused
|
|
*/
|
|
AVPacket attached_pic;
|
|
|
|
/*****************************************************************
|
|
* All fields below this line are not part of the public API. They
|
|
* may not be used outside of libavformat and can be changed and
|
|
* removed at will.
|
|
* New public fields should be added right above.
|
|
*****************************************************************
|
|
*/
|
|
|
|
/**
|
|
* Stream information used internally by av_find_stream_info()
|
|
*/
|
|
#define MAX_STD_TIMEBASES (60*12+5)
|
|
struct {
|
|
#if FF_API_R_FRAME_RATE
|
|
int64_t last_dts;
|
|
int64_t duration_gcd;
|
|
int duration_count;
|
|
double duration_error[MAX_STD_TIMEBASES];
|
|
#endif
|
|
int nb_decoded_frames;
|
|
int found_decoder;
|
|
|
|
/**
|
|
* Those are used for average framerate estimation.
|
|
*/
|
|
int64_t fps_first_dts;
|
|
int fps_first_dts_idx;
|
|
int64_t fps_last_dts;
|
|
int fps_last_dts_idx;
|
|
|
|
} *info;
|
|
|
|
int pts_wrap_bits; /**< number of bits in pts (used for wrapping control) */
|
|
|
|
// Timestamp generation support:
|
|
/**
|
|
* Timestamp corresponding to the last dts sync point.
|
|
*
|
|
* Initialized when AVCodecParserContext.dts_sync_point >= 0 and
|
|
* a DTS is received from the underlying container. Otherwise set to
|
|
* AV_NOPTS_VALUE by default.
|
|
*/
|
|
int64_t reference_dts;
|
|
int64_t first_dts;
|
|
int64_t cur_dts;
|
|
int64_t last_IP_pts;
|
|
int last_IP_duration;
|
|
|
|
/**
|
|
* Number of packets to buffer for codec probing
|
|
*/
|
|
#define MAX_PROBE_PACKETS 2500
|
|
int probe_packets;
|
|
|
|
/**
|
|
* Number of frames that have been demuxed during av_find_stream_info()
|
|
*/
|
|
int codec_info_nb_frames;
|
|
|
|
/* av_read_frame() support */
|
|
enum AVStreamParseType need_parsing;
|
|
struct AVCodecParserContext *parser;
|
|
|
|
/**
|
|
* last packet in packet_buffer for this stream when muxing.
|
|
*/
|
|
struct AVPacketList *last_in_packet_buffer;
|
|
AVProbeData probe_data;
|
|
#define MAX_REORDER_DELAY 16
|
|
int64_t pts_buffer[MAX_REORDER_DELAY+1];
|
|
|
|
AVIndexEntry *index_entries; /**< Only used if the format does not
|
|
support seeking natively. */
|
|
int nb_index_entries;
|
|
unsigned int index_entries_allocated_size;
|
|
} AVStream;
|
|
|
|
#define AV_PROGRAM_RUNNING 1
|
|
|
|
/**
|
|
* New fields can be added to the end with minor version bumps.
|
|
* Removal, reordering and changes to existing fields require a major
|
|
* version bump.
|
|
* sizeof(AVProgram) must not be used outside libav*.
|
|
*/
|
|
typedef struct AVProgram {
|
|
int id;
|
|
int flags;
|
|
enum AVDiscard discard; ///< selects which program to discard and which to feed to the caller
|
|
unsigned int *stream_index;
|
|
unsigned int nb_stream_indexes;
|
|
AVDictionary *metadata;
|
|
} AVProgram;
|
|
|
|
#define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
|
|
(streams are added dynamically) */
|
|
|
|
typedef struct AVChapter {
|
|
int id; ///< unique ID to identify the chapter
|
|
AVRational time_base; ///< time base in which the start/end timestamps are specified
|
|
int64_t start, end; ///< chapter start/end time in time_base units
|
|
AVDictionary *metadata;
|
|
} AVChapter;
|
|
|
|
/**
|
|
* Format I/O context.
|
|
* New fields can be added to the end with minor version bumps.
|
|
* Removal, reordering and changes to existing fields require a major
|
|
* version bump.
|
|
* sizeof(AVFormatContext) must not be used outside libav*, use
|
|
* avformat_alloc_context() to create an AVFormatContext.
|
|
*/
|
|
typedef struct AVFormatContext {
|
|
/**
|
|
* A class for logging and AVOptions. Set by avformat_alloc_context().
|
|
* Exports (de)muxer private options if they exist.
|
|
*/
|
|
const AVClass *av_class;
|
|
|
|
/**
|
|
* Can only be iformat or oformat, not both at the same time.
|
|
*
|
|
* decoding: set by avformat_open_input().
|
|
* encoding: set by the user.
|
|
*/
|
|
struct AVInputFormat *iformat;
|
|
struct AVOutputFormat *oformat;
|
|
|
|
/**
|
|
* Format private data. This is an AVOptions-enabled struct
|
|
* if and only if iformat/oformat.priv_class is not NULL.
|
|
*/
|
|
void *priv_data;
|
|
|
|
/**
|
|
* I/O context.
|
|
*
|
|
* decoding: either set by the user before avformat_open_input() (then
|
|
* the user must close it manually) or set by avformat_open_input().
|
|
* encoding: set by the user.
|
|
*
|
|
* Do NOT set this field if AVFMT_NOFILE flag is set in
|
|
* iformat/oformat.flags. In such a case, the (de)muxer will handle
|
|
* I/O in some other way and this field will be NULL.
|
|
*/
|
|
AVIOContext *pb;
|
|
|
|
/* stream info */
|
|
int ctx_flags; /**< Format-specific flags, see AVFMTCTX_xx */
|
|
|
|
/**
|
|
* A list of all streams in the file. New streams are created with
|
|
* avformat_new_stream().
|
|
*
|
|
* decoding: streams are created by libavformat in avformat_open_input().
|
|
* If AVFMTCTX_NOHEADER is set in ctx_flags, then new streams may also
|
|
* appear in av_read_frame().
|
|
* encoding: streams are created by the user before avformat_write_header().
|
|
*/
|
|
unsigned int nb_streams;
|
|
AVStream **streams;
|
|
|
|
char filename[1024]; /**< input or output filename */
|
|
|
|
/**
|
|
* Decoding: position of the first frame of the component, in
|
|
* AV_TIME_BASE fractional seconds. NEVER set this value directly:
|
|
* It is deduced from the AVStream values.
|
|
*/
|
|
int64_t start_time;
|
|
|
|
/**
|
|
* Decoding: duration of the stream, in AV_TIME_BASE fractional
|
|
* seconds. Only set this value if you know none of the individual stream
|
|
* durations and also do not set any of them. This is deduced from the
|
|
* AVStream values if not set.
|
|
*/
|
|
int64_t duration;
|
|
|
|
/**
|
|
* Decoding: total stream bitrate in bit/s, 0 if not
|
|
* available. Never set it directly if the file_size and the
|
|
* duration are known as Libav can compute it automatically.
|
|
*/
|
|
int bit_rate;
|
|
|
|
unsigned int packet_size;
|
|
int max_delay;
|
|
|
|
int flags;
|
|
#define AVFMT_FLAG_GENPTS 0x0001 ///< Generate missing pts even if it requires parsing future frames.
|
|
#define AVFMT_FLAG_IGNIDX 0x0002 ///< Ignore index.
|
|
#define AVFMT_FLAG_NONBLOCK 0x0004 ///< Do not block when reading packets from input.
|
|
#define AVFMT_FLAG_IGNDTS 0x0008 ///< Ignore DTS on frames that contain both DTS & PTS
|
|
#define AVFMT_FLAG_NOFILLIN 0x0010 ///< Do not infer any values from other values, just return what is stored in the container
|
|
#define AVFMT_FLAG_NOPARSE 0x0020 ///< Do not use AVParsers, you also must set AVFMT_FLAG_NOFILLIN as the fillin code works on frames and no parsing -> no frames. Also seeking to frames can not work if parsing to find frame boundaries has been disabled
|
|
#define AVFMT_FLAG_NOBUFFER 0x0040 ///< Do not buffer frames when possible
|
|
#define AVFMT_FLAG_CUSTOM_IO 0x0080 ///< The caller has supplied a custom AVIOContext, don't avio_close() it.
|
|
#define AVFMT_FLAG_DISCARD_CORRUPT 0x0100 ///< Discard frames marked corrupted
|
|
|
|
/**
|
|
* decoding: size of data to probe; encoding: unused.
|
|
*/
|
|
unsigned int probesize;
|
|
|
|
/**
|
|
* decoding: maximum time (in AV_TIME_BASE units) during which the input should
|
|
* be analyzed in avformat_find_stream_info().
|
|
*/
|
|
int max_analyze_duration;
|
|
|
|
const uint8_t *key;
|
|
int keylen;
|
|
|
|
unsigned int nb_programs;
|
|
AVProgram **programs;
|
|
|
|
/**
|
|
* Forced video codec_id.
|
|
* Demuxing: Set by user.
|
|
*/
|
|
enum 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;
|
|
|
|
/**
|
|
* Maximum amount of memory in bytes to use for the index of each stream.
|
|
* If the index exceeds this size, entries will be discarded as
|
|
* needed to maintain a smaller size. This can lead to slower or less
|
|
* accurate seeking (depends on demuxer).
|
|
* Demuxers for which a full in-memory index is mandatory will ignore
|
|
* this.
|
|
* muxing : unused
|
|
* demuxing: set by user
|
|
*/
|
|
unsigned int max_index_size;
|
|
|
|
/**
|
|
* Maximum amount of memory in bytes to use for buffering frames
|
|
* obtained from realtime capture devices.
|
|
*/
|
|
unsigned int max_picture_buffer;
|
|
|
|
unsigned int nb_chapters;
|
|
AVChapter **chapters;
|
|
|
|
AVDictionary *metadata;
|
|
|
|
/**
|
|
* Start time of the stream in real world time, in microseconds
|
|
* since the unix epoch (00:00 1st January 1970). That is, pts=0
|
|
* in the stream was captured at this real world time.
|
|
* - encoding: Set by user.
|
|
* - decoding: Unused.
|
|
*/
|
|
int64_t start_time_realtime;
|
|
|
|
/**
|
|
* decoding: number of frames used to probe fps
|
|
*/
|
|
int fps_probe_size;
|
|
|
|
/**
|
|
* Error recognition; higher values will detect more errors but may
|
|
* misdetect some more or less valid parts as errors.
|
|
* - encoding: unused
|
|
* - decoding: Set by user.
|
|
*/
|
|
int error_recognition;
|
|
|
|
/**
|
|
* Custom interrupt callbacks for the I/O layer.
|
|
*
|
|
* decoding: set by the user before avformat_open_input().
|
|
* encoding: set by the user before avformat_write_header()
|
|
* (mainly useful for AVFMT_NOFILE formats). The callback
|
|
* should also be passed to avio_open2() if it's used to
|
|
* open the file.
|
|
*/
|
|
AVIOInterruptCB interrupt_callback;
|
|
|
|
/**
|
|
* Flags to enable debugging.
|
|
*/
|
|
int debug;
|
|
#define FF_FDEBUG_TS 0x0001
|
|
/*****************************************************************
|
|
* All fields below this line are not part of the public API. They
|
|
* may not be used outside of libavformat and can be changed and
|
|
* removed at will.
|
|
* New public fields should be added right above.
|
|
*****************************************************************
|
|
*/
|
|
|
|
/**
|
|
* This buffer is only needed when packets were already buffered but
|
|
* not decoded, for example to get the codec parameters in MPEG
|
|
* streams.
|
|
*/
|
|
struct AVPacketList *packet_buffer;
|
|
struct AVPacketList *packet_buffer_end;
|
|
|
|
/* av_seek_frame() support */
|
|
int64_t data_offset; /**< offset of the first packet */
|
|
|
|
/**
|
|
* Raw packets from the demuxer, prior to parsing and decoding.
|
|
* This buffer is used for buffering packets until the codec can
|
|
* be identified, as parsing cannot be done without knowing the
|
|
* codec.
|
|
*/
|
|
struct AVPacketList *raw_packet_buffer;
|
|
struct AVPacketList *raw_packet_buffer_end;
|
|
/**
|
|
* Packets split by the parser get queued here.
|
|
*/
|
|
struct AVPacketList *parse_queue;
|
|
struct AVPacketList *parse_queue_end;
|
|
/**
|
|
* Remaining size available for raw_packet_buffer, in bytes.
|
|
*/
|
|
#define RAW_PACKET_BUFFER_SIZE 2500000
|
|
int raw_packet_buffer_remaining_size;
|
|
} AVFormatContext;
|
|
|
|
typedef struct AVPacketList {
|
|
AVPacket pkt;
|
|
struct AVPacketList *next;
|
|
} AVPacketList;
|
|
|
|
|
|
/**
|
|
* @defgroup lavf_core Core functions
|
|
* @ingroup libavf
|
|
*
|
|
* Functions for querying libavformat capabilities, allocating core structures,
|
|
* etc.
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* Return the LIBAVFORMAT_VERSION_INT constant.
|
|
*/
|
|
unsigned avformat_version(void);
|
|
|
|
/**
|
|
* Return the libavformat build-time configuration.
|
|
*/
|
|
const char *avformat_configuration(void);
|
|
|
|
/**
|
|
* Return the libavformat license.
|
|
*/
|
|
const char *avformat_license(void);
|
|
|
|
/**
|
|
* Initialize libavformat and register all the muxers, demuxers and
|
|
* protocols. If you do not call this function, then you can select
|
|
* exactly which formats you want to support.
|
|
*
|
|
* @see av_register_input_format()
|
|
* @see av_register_output_format()
|
|
* @see av_register_protocol()
|
|
*/
|
|
void av_register_all(void);
|
|
|
|
void av_register_input_format(AVInputFormat *format);
|
|
void av_register_output_format(AVOutputFormat *format);
|
|
|
|
/**
|
|
* Do global initialization of network components. This is optional,
|
|
* but recommended, since it avoids the overhead of implicitly
|
|
* doing the setup for each session.
|
|
*
|
|
* Calling this function will become mandatory if using network
|
|
* protocols at some major version bump.
|
|
*/
|
|
int avformat_network_init(void);
|
|
|
|
/**
|
|
* Undo the initialization done by avformat_network_init.
|
|
*/
|
|
int avformat_network_deinit(void);
|
|
|
|
/**
|
|
* If f is NULL, returns the first registered input format,
|
|
* if f is non-NULL, returns the next registered input format after f
|
|
* or NULL if f is the last one.
|
|
*/
|
|
AVInputFormat *av_iformat_next(AVInputFormat *f);
|
|
|
|
/**
|
|
* If f is NULL, returns the first registered output format,
|
|
* if f is non-NULL, returns the next registered output format after f
|
|
* or NULL if f is the last one.
|
|
*/
|
|
AVOutputFormat *av_oformat_next(AVOutputFormat *f);
|
|
|
|
/**
|
|
* Allocate an AVFormatContext.
|
|
* avformat_free_context() can be used to free the context and everything
|
|
* allocated by the framework within it.
|
|
*/
|
|
AVFormatContext *avformat_alloc_context(void);
|
|
|
|
/**
|
|
* Free an AVFormatContext and all its streams.
|
|
* @param s context to free
|
|
*/
|
|
void avformat_free_context(AVFormatContext *s);
|
|
|
|
/**
|
|
* Get the AVClass for AVFormatContext. It can be used in combination with
|
|
* AV_OPT_SEARCH_FAKE_OBJ for examining options.
|
|
*
|
|
* @see av_opt_find().
|
|
*/
|
|
const AVClass *avformat_get_class(void);
|
|
|
|
/**
|
|
* Add a new stream to a media file.
|
|
*
|
|
* When demuxing, it is called by the demuxer in read_header(). If the
|
|
* flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
|
|
* be called in read_packet().
|
|
*
|
|
* When muxing, should be called by the user before avformat_write_header().
|
|
*
|
|
* @param c If non-NULL, the AVCodecContext corresponding to the new stream
|
|
* will be initialized to use this codec. This is needed for e.g. codec-specific
|
|
* defaults to be set, so codec should be provided if it is known.
|
|
*
|
|
* @return newly created stream or NULL on error.
|
|
*/
|
|
AVStream *avformat_new_stream(AVFormatContext *s, AVCodec *c);
|
|
|
|
AVProgram *av_new_program(AVFormatContext *s, int id);
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
|
|
/**
|
|
* @addtogroup lavf_decoding
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* Find AVInputFormat based on the short name of the input format.
|
|
*/
|
|
AVInputFormat *av_find_input_format(const char *short_name);
|
|
|
|
/**
|
|
* Guess the file format.
|
|
*
|
|
* @param is_opened Whether the file is already opened; determines whether
|
|
* demuxers with or without AVFMT_NOFILE are probed.
|
|
*/
|
|
AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
|
|
|
|
/**
|
|
* Guess the file format.
|
|
*
|
|
* @param is_opened Whether the file is already opened; determines whether
|
|
* demuxers with or without AVFMT_NOFILE are probed.
|
|
* @param score_max A probe score larger that this is required to accept a
|
|
* detection, the variable is set to the actual detection
|
|
* score afterwards.
|
|
* If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended
|
|
* to retry with a larger probe buffer.
|
|
*/
|
|
AVInputFormat *av_probe_input_format2(AVProbeData *pd, int is_opened, int *score_max);
|
|
|
|
/**
|
|
* Probe a bytestream to determine the input format. Each time a probe returns
|
|
* with a score that is too low, the probe buffer size is increased and another
|
|
* attempt is made. When the maximum probe size is reached, the input format
|
|
* with the highest score is returned.
|
|
*
|
|
* @param pb the bytestream to probe
|
|
* @param fmt the input format is put here
|
|
* @param filename the filename of the stream
|
|
* @param logctx the log context
|
|
* @param offset the offset within the bytestream to probe from
|
|
* @param max_probe_size the maximum probe buffer size (zero for default)
|
|
* @return 0 in case of success, a negative value corresponding to an
|
|
* AVERROR code otherwise
|
|
*/
|
|
int av_probe_input_buffer(AVIOContext *pb, AVInputFormat **fmt,
|
|
const char *filename, void *logctx,
|
|
unsigned int offset, unsigned int max_probe_size);
|
|
|
|
/**
|
|
* Open an input stream and read the header. The codecs are not opened.
|
|
* The stream must be closed with av_close_input_file().
|
|
*
|
|
* @param ps Pointer to user-supplied AVFormatContext (allocated by avformat_alloc_context).
|
|
* May be a pointer to NULL, in which case an AVFormatContext is allocated by this
|
|
* function and written into ps.
|
|
* Note that a user-supplied AVFormatContext will be freed on failure.
|
|
* @param filename Name of the stream to open.
|
|
* @param fmt If non-NULL, this parameter forces a specific input format.
|
|
* Otherwise the format is autodetected.
|
|
* @param options A dictionary filled with AVFormatContext and demuxer-private options.
|
|
* On return this parameter will be destroyed and replaced with a dict containing
|
|
* options that were not found. May be NULL.
|
|
*
|
|
* @return 0 on success, a negative AVERROR on failure.
|
|
*
|
|
* @note If you want to use custom IO, preallocate the format context and set its pb field.
|
|
*/
|
|
int avformat_open_input(AVFormatContext **ps, const char *filename, AVInputFormat *fmt, AVDictionary **options);
|
|
|
|
/**
|
|
* 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 "best" stream in the file.
|
|
* The best stream is determined according to various heuristics as the most
|
|
* likely to be what the user expects.
|
|
* If the decoder parameter is non-NULL, av_find_best_stream will find the
|
|
* default decoder for the stream's codec; streams for which no decoder can
|
|
* be found are ignored.
|
|
*
|
|
* @param ic media file handle
|
|
* @param type stream type: video, audio, subtitles, etc.
|
|
* @param wanted_stream_nb user-requested stream number,
|
|
* or -1 for automatic selection
|
|
* @param related_stream try to find a stream related (eg. in the same
|
|
* program) to this one, or -1 if none
|
|
* @param decoder_ret if non-NULL, returns the decoder for the
|
|
* selected stream
|
|
* @param flags flags; none are currently defined
|
|
* @return the non-negative stream number in case of success,
|
|
* AVERROR_STREAM_NOT_FOUND if no stream with the requested type
|
|
* could be found,
|
|
* AVERROR_DECODER_NOT_FOUND if streams were found but no decoder
|
|
* @note If av_find_best_stream returns successfully and decoder_ret is not
|
|
* NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec.
|
|
*/
|
|
int av_find_best_stream(AVFormatContext *ic,
|
|
enum AVMediaType type,
|
|
int wanted_stream_nb,
|
|
int related_stream,
|
|
AVCodec **decoder_ret,
|
|
int flags);
|
|
|
|
/**
|
|
* 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.
|
|
*
|
|
* If pkt->buf is NULL, then the packet is valid until the next
|
|
* av_read_frame() or until av_close_input_file(). Otherwise the packet is valid
|
|
* indefinitely. In both cases the packet must be freed with
|
|
* av_free_packet when it is no longer needed. For video, the packet contains
|
|
* exactly one frame. For audio, it contains an integer number of frames if each
|
|
* frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames
|
|
* have a variable size (e.g. MPEG audio), then it contains one frame.
|
|
*
|
|
* pkt->pts, pkt->dts and pkt->duration are always set to correct
|
|
* values in AVStream.time_base units (and guessed if the format cannot
|
|
* provide them). pkt->pts can be AV_NOPTS_VALUE if the video format
|
|
* has B-frames, so it is better to rely on pkt->dts if you do not
|
|
* decompress the payload.
|
|
*
|
|
* @return 0 if OK, < 0 on error or end of file
|
|
*/
|
|
int av_read_frame(AVFormatContext *s, AVPacket *pkt);
|
|
|
|
/**
|
|
* Seek to the keyframe at timestamp.
|
|
* 'timestamp' in 'stream_index'.
|
|
* @param stream_index If stream_index is (-1), a default
|
|
* stream is selected, and timestamp is automatically converted
|
|
* from AV_TIME_BASE units to the stream specific time_base.
|
|
* @param timestamp Timestamp in AVStream.time_base units
|
|
* or, if no stream is specified, in AV_TIME_BASE units.
|
|
* @param flags flags which select direction and seeking mode
|
|
* @return >= 0 on success
|
|
*/
|
|
int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp,
|
|
int flags);
|
|
|
|
/**
|
|
* Seek to timestamp ts.
|
|
* Seeking will be done so that the point from which all active streams
|
|
* can be presented successfully will be closest to ts and within min/max_ts.
|
|
* Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
|
|
*
|
|
* If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and
|
|
* are the file position (this may not be supported by all demuxers).
|
|
* If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames
|
|
* in the stream with stream_index (this may not be supported by all demuxers).
|
|
* Otherwise all timestamps are in units of the stream selected by stream_index
|
|
* or if stream_index is -1, in AV_TIME_BASE units.
|
|
* If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as
|
|
* keyframes (this may not be supported by all demuxers).
|
|
*
|
|
* @param stream_index index of the stream which is used as time base reference
|
|
* @param min_ts smallest acceptable timestamp
|
|
* @param ts target timestamp
|
|
* @param max_ts largest acceptable timestamp
|
|
* @param flags flags
|
|
* @return >=0 on success, error code otherwise
|
|
*
|
|
* @note This is part of the new seek API which is still under construction.
|
|
* Thus do not use this yet. It may change at any time, do not expect
|
|
* ABI compatibility yet!
|
|
*/
|
|
int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
|
|
|
|
/**
|
|
* Start playing a network-based stream (e.g. RTSP stream) at the
|
|
* current position.
|
|
*/
|
|
int av_read_play(AVFormatContext *s);
|
|
|
|
/**
|
|
* Pause a network-based stream (e.g. RTSP stream).
|
|
*
|
|
* Use av_read_play() to resume it.
|
|
*/
|
|
int av_read_pause(AVFormatContext *s);
|
|
|
|
/**
|
|
* 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 ///< seek backward
|
|
#define AVSEEK_FLAG_BYTE 2 ///< seeking based on position in bytes
|
|
#define AVSEEK_FLAG_ANY 4 ///< seek to any frame, even non-keyframes
|
|
#define AVSEEK_FLAG_FRAME 8 ///< seeking based on frame number
|
|
|
|
/**
|
|
* @addtogroup lavf_encoding
|
|
* @{
|
|
*/
|
|
/**
|
|
* Allocate the stream private data and write the stream header to
|
|
* an output media file.
|
|
*
|
|
* @param s Media file handle, must be allocated with avformat_alloc_context().
|
|
* Its oformat field must be set to the desired output format;
|
|
* Its pb field must be set to an already openened AVIOContext.
|
|
* @param options An AVDictionary filled with AVFormatContext and muxer-private options.
|
|
* On return this parameter will be destroyed and replaced with a dict containing
|
|
* options that were not found. May be NULL.
|
|
*
|
|
* @return 0 on success, negative AVERROR on failure.
|
|
*
|
|
* @see av_opt_find, av_dict_set, avio_open, av_oformat_next.
|
|
*/
|
|
int avformat_write_header(AVFormatContext *s, AVDictionary **options);
|
|
|
|
/**
|
|
* Write a packet to an output media file.
|
|
*
|
|
* The packet shall contain one audio or video frame.
|
|
* The packet must be correctly interleaved according to the container
|
|
* specification, if not then av_interleaved_write_frame must be used.
|
|
*
|
|
* @param s media file handle
|
|
* @param pkt The packet, which contains the stream_index, buf/buf_size,
|
|
* dts/pts, ...
|
|
* This can be NULL (at any time, not just at the end), in
|
|
* order to immediately flush data buffered within the muxer,
|
|
* for muxers that buffer up data internally before writing it
|
|
* to the output.
|
|
* @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush
|
|
*/
|
|
int av_write_frame(AVFormatContext *s, AVPacket *pkt);
|
|
|
|
/**
|
|
* Write a packet to an output media file ensuring correct interleaving.
|
|
*
|
|
* The packet must contain one audio or video frame.
|
|
* If the packets are already correctly interleaved, the application should
|
|
* call av_write_frame() instead as it is slightly faster. It is also important
|
|
* to keep in mind that completely non-interleaved input will need huge amounts
|
|
* of memory to interleave with this, so it is preferable to interleave at the
|
|
* demuxer level.
|
|
*
|
|
* @param s media file handle
|
|
* @param pkt The packet containing the data to be written. pkt->buf must be set
|
|
* to a valid AVBufferRef describing the packet data. Libavformat takes
|
|
* ownership of this reference and will unref it when it sees fit. The caller
|
|
* must not access the data through this reference after this function returns.
|
|
* This can be NULL (at any time, not just at the end), to flush the
|
|
* interleaving queues.
|
|
* Packet's @ref AVPacket.stream_index "stream_index" field must be set to the
|
|
* index of the corresponding stream in @ref AVFormatContext.streams
|
|
* "s.streams".
|
|
* It is very strongly recommended that timing information (@ref AVPacket.pts
|
|
* "pts", @ref AVPacket.dts "dts" @ref AVPacket.duration "duration") is set to
|
|
* correct values.
|
|
*
|
|
* @return 0 on success, a negative AVERROR on error.
|
|
*/
|
|
int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt);
|
|
|
|
#if FF_API_INTERLEAVE_PACKET
|
|
/**
|
|
* @deprecated this function was never meant to be called by the user
|
|
* programs.
|
|
*/
|
|
attribute_deprecated
|
|
int av_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
|
|
AVPacket *pkt, int flush);
|
|
#endif
|
|
|
|
/**
|
|
* Write the stream trailer to an output media file and free the
|
|
* file private data.
|
|
*
|
|
* May only be called after a successful call to 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
|
|
*/
|
|
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(AVOutputFormat *fmt, const char *short_name,
|
|
const char *filename, const char *mime_type,
|
|
enum AVMediaType type);
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
|
|
/**
|
|
* @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, AVPacket *pkt, int dump_payload, AVStream *st);
|
|
|
|
|
|
/**
|
|
* Send a nice dump of a packet to the log.
|
|
*
|
|
* @param avcl A pointer to an arbitrary struct of which the first field is a
|
|
* pointer to an AVClass struct.
|
|
* @param level The importance level of the message, lower values signifying
|
|
* higher importance.
|
|
* @param pkt packet to dump
|
|
* @param dump_payload True if the payload must be displayed, too.
|
|
* @param st AVStream that the packet belongs to
|
|
*/
|
|
void av_pkt_dump_log2(void *avcl, int level, AVPacket *pkt, int dump_payload,
|
|
AVStream *st);
|
|
|
|
/**
|
|
* Get the 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
|
|
*/
|
|
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
|
|
*/
|
|
unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id);
|
|
|
|
int av_find_default_stream_index(AVFormatContext *s);
|
|
|
|
/**
|
|
* Get the index for a specific timestamp.
|
|
* @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond
|
|
* to the timestamp which is <= the requested one, if backward
|
|
* is 0, then it will be >=
|
|
* if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise
|
|
* @return < 0 if no such timestamp could be found
|
|
*/
|
|
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags);
|
|
|
|
/**
|
|
* Add an index entry into a sorted list. Update the entry if the list
|
|
* already contains it.
|
|
*
|
|
* @param timestamp timestamp in the time base of the given stream
|
|
*/
|
|
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp,
|
|
int size, int distance, int flags);
|
|
|
|
|
|
/**
|
|
* Split a URL string into components.
|
|
*
|
|
* The pointers to buffers for storing individual components may be null,
|
|
* in order to ignore that component. Buffers for components not found are
|
|
* set to empty strings. If the port is not found, it is set to a negative
|
|
* value.
|
|
*
|
|
* @param proto the buffer for the protocol
|
|
* @param proto_size the size of the proto buffer
|
|
* @param authorization the buffer for the authorization
|
|
* @param authorization_size the size of the authorization buffer
|
|
* @param hostname the buffer for the host name
|
|
* @param hostname_size the size of the hostname buffer
|
|
* @param port_ptr a pointer to store the port number in
|
|
* @param path the buffer for the path
|
|
* @param path_size the size of the path buffer
|
|
* @param url the URL to split
|
|
*/
|
|
void av_url_split(char *proto, int proto_size,
|
|
char *authorization, int authorization_size,
|
|
char *hostname, int hostname_size,
|
|
int *port_ptr,
|
|
char *path, int path_size,
|
|
const char *url);
|
|
|
|
|
|
void av_dump_format(AVFormatContext *ic,
|
|
int index,
|
|
const char *url,
|
|
int is_output);
|
|
|
|
/**
|
|
* Return in 'buf' the path with '%d' replaced by a number.
|
|
*
|
|
* Also handles the '%0nd' format where 'n' is the total number
|
|
* of digits and '%%'.
|
|
*
|
|
* @param buf destination buffer
|
|
* @param buf_size destination buffer size
|
|
* @param path numbered sequence string
|
|
* @param number frame number
|
|
* @return 0 if OK, -1 on format error
|
|
*/
|
|
int av_get_frame_filename(char *buf, int buf_size,
|
|
const char *path, int number);
|
|
|
|
/**
|
|
* Check whether filename actually is a numbered sequence generator.
|
|
*
|
|
* @param filename possible numbered sequence string
|
|
* @return 1 if a valid numbered sequence string, 0 otherwise
|
|
*/
|
|
int av_filename_number_test(const char *filename);
|
|
|
|
/**
|
|
* Generate an SDP for an RTP session.
|
|
*
|
|
* 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 extensions a comma-separated list of filename extensions
|
|
*/
|
|
int av_match_ext(const char *filename, const char *extensions);
|
|
|
|
/**
|
|
* Test if the given container can store a codec.
|
|
*
|
|
* @param std_compliance standards compliance level, one of FF_COMPLIANCE_*
|
|
*
|
|
* @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot.
|
|
* A negative number if this information is not available.
|
|
*/
|
|
int avformat_query_codec(AVOutputFormat *ofmt, enum 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);
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
/**
|
|
* @}
|
|
*/
|
|
|
|
#endif /* AVFORMAT_AVFORMAT_H */
|