lavf doxy: add some general lavf information.

This commit is contained in:
Anton Khirnov 2011-12-11 09:05:11 +01:00
parent abf2c2d787
commit ccbc106841
1 changed files with 35 additions and 0 deletions

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@ -31,6 +31,41 @@
* @defgroup libavf I/O and Muxing/Demuxing Library
* @{
*
* Libavformat (lavf) is a library for dealing with various media container
* formats. Its main two purposes are demuxing - i.e. splitting a media file
* into component streams, and the reverse process of muxing - writing supplied
* data in a specified container format. It also has an @ref lavf_io
* "I/O module" which supports a number of protocols for accessing the data (e.g.
* file, tcp, http and others). Before using lavf, you need to call
* av_register_all() to register all compiled muxers, demuxers and protocols.
* Unless you are absolutely sure you won't use libavformat's network
* capabilities, you should also call avformat_network_init().
*
* A supported input format is described by an AVInputFormat struct, conversely
* an output format is described by AVOutputFormat. You can iterate over all
* registered input/output formats using the av_iformat_next() /
* av_oformat_next() functions. The protocols layer is not part of the public
* API, so you can only get the names of supported protocols with the
* avio_enum_protocols() function.
*
* Main lavf structure used for both muxing and demuxing is AVFormatContext,
* which exports all information about the file being read or written. As with
* most Libav 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).
*
* @defgroup lavf_decoding Demuxing
* @{
* @}