APIchanges

  major version. Use AV_PKT_FLAG_KEY instead.

2009-06-01 - f988ce6 - lavc 52.30.0 - av_lockmgr_register()
  av_lockmgr_register() can be used to register a callback function
  that lavc (and in the future, libraries that depend on lavc) can use
  to implement mutexes. The application should provide a callback function
  that implements the AV_LOCK_* operations described in avcodec.h.
  When the lock manager is registered, FFmpeg is guaranteed to behave
  correctly in a multi-threaded application.

2009-04-30 - ce1d9c8 - lavc 52.28.0 - av_free_packet()
  av_free_packet() is no longer an inline function. It is now exported.

2009-04-11 - 80d403f - lavc 52.25.0 - deprecate av_destruct_packet_nofree()
  Please use NULL instead. This has been supported since r16506
  (lavf > 52.23.1, lavc > 52.10.0).

2009-04-07 - 7a00bba - lavc 52.23.0 - avcodec_decode_video/audio/subtitle
  The old decoding functions are deprecated, all new code should use the
  new functions avcodec_decode_video2(), avcodec_decode_audio3() and
  avcodec_decode_subtitle2(). These new functions take an AVPacket *pkt
  argument instead of a const uint8_t *buf / int buf_size pair.

2009-04-03 - 7b09db3 - lavu 50.3.0 - av_fifo_space()
  Introduce the av_fifo_space() function.

2009-04-02 - fabd246 - lavc 52.23.0 - AVPacket
  Move AVPacket declaration from libavformat/avformat.h to
  libavcodec/avcodec.h.

2009-03-22 - 6e08ca9 - lavu 50.2.0 - RGB32 pixel formats
  Convert the pixel formats PIX_FMT_ARGB, PIX_FMT_RGBA, PIX_FMT_ABGR,
  PIX_FMT_BGRA, which were defined as macros, into enum PixelFormat values.
  Conversely PIX_FMT_RGB32, PIX_FMT_RGB32_1, PIX_FMT_BGR32 and
  PIX_FMT_BGR32_1 are now macros.
  avcodec_get_pix_fmt() now recognizes the "rgb32" and "bgr32" aliases.
  Re-sort the enum PixelFormat list accordingly.
  This change breaks API/ABI backward compatibility.

2009-03-22 - f82674e - lavu 50.1.0 - PIX_FMT_RGB5X5 endian variants
  Add the enum PixelFormat values:
  PIX_FMT_RGB565BE, PIX_FMT_RGB565LE, PIX_FMT_RGB555BE, PIX_FMT_RGB555LE,
  PIX_FMT_BGR565BE, PIX_FMT_BGR565LE, PIX_FMT_BGR555BE, PIX_FMT_BGR555LE.

2009-03-21 - ee6624e - lavu 50.0.0  - av_random*
  The Mersenne Twister PRNG implemented through the av_random* functions
  was removed. Use the lagged Fibonacci PRNG through the av_lfg* functions
  instead.

2009-03-08 - 41dd680 - 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
  was 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 - ec26457 - 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