Never assume the API of libav* to be stable unless at least 1 week has passed sincethe last major version increase.The last version increases were:libavcodec:  ?libavdevice: ?libavfilter: ?libavformat: ?libpostproc: ?libswscale:  ?libavutil:   2009-03-08  API changes, most recent first: 2009-03-08 - r17869 - lavu 50.0.0  - AVFifoBuffer  av_fifo_init, av_fifo_read, av_fifo_write and av_fifo_realloc were dropped  and replaced by av_fifo_alloc, av_fifo_generic_read, av_fifo_generic_write  and av_fifo_realloc2.  In addition, the order of the function arguments of av_fifo_generic_read  were changed to match av_fifo_generic_write.  The AVFifoBuffer/struct AVFifoBuffer may only be used in an opaque way by  applications, they may not use sizeof() or directly access members. 2009-03-01 - r17682 - lavf 52.31.0 - Generic metadata API  Introduce a new metadata API (see av_metadata_get() and friends).  The old API is now deprecated and should not be used anymore. This especially  includes the following structure fields:    - AVFormatContext.title    - AVFormatContext.author    - AVFormatContext.copyright    - AVFormatContext.comment    - AVFormatContext.album    - AVFormatContext.year    - AVFormatContext.track    - AVFormatContext.genre    - AVStream.language    - AVStream.filename    - AVProgram.provider_name    - AVProgram.name    - AVChapter.title