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: 2009-10-18libavformat: ?libpostproc: ?libswscale:  ?libavutil:   2009-03-08  API changes, most recent first: 2010-03-06 - r22251 - lavu 50.11.0 - av_stristr()  Add av_stristr(). 2010-03-03 - r22174 - lavu 50.10.0 - av_tree_enumerate()  Add av_tree_enumerate(). 2010-02-07 - r21673 - lavu 50.9.0 - av_compare_ts()  Add av_compare_ts(). 2010-02-05 - r30513 - lsws 0.10.0 - sws_getCoefficients()  Add sws_getCoefficients(). 2010-02-01 - r21587 - lavf 52.50.0 - metadata API  Add a list of generic tag names, change 'author' -> 'artist',  'year' -> 'date'. 2010-01-30 - r21545 - lavu 50.8.0 - av_get_pix_fmt()  Add av_get_pix_fmt(). 2010-01-21 - r30381 - lsws 0.9.0 - sws_scale  Change constness attributes of sws_scale() parameters. 2010-01-10 - r21121 - lavfi 1.15.0 - avfilter_graph_config_links()  Add a log_ctx parameter to avfilter_graph_config_links(). 2010-01-07 - r30236 - lsws 0.8.0 - sws_isSupported{In,Out}put  Add sws_isSupportedInput() and sws_isSupportedOutput() functions. 2010-01-06 - r21035 - lavfi 1.14.0 - avfilter_add_colorspace()  Change the avfilter_add_colorspace() signature, make it accept an  (AVFilterFormats **) rather than an (AVFilterFormats *) as before. 2010-01-03 - r21007 - lavfi 1.13.0 - avfilter_add_colorspace()  Add avfilter_add_colorspace(). 2010-01-02 - r20998 - lavf 52.46.0 - av_match_ext()  Add av_match_ext(), it should be used in place of match_ext(). 2010-01-01 - r20991 - lavf 52.45.0 - av_guess_format()  Add av_guess_format(), it should be used in place of guess_format(). 2009-12-13 - r20834 - lavf 52.43.0 - metadata API  Add av_metadata_set2(), AV_METADATA_DONT_STRDUP_KEY and AV_METADATA_DONT_STRDUP_VAL. 2009-12-13 - r20829 - lavu 50.7.0 - avstring.h API  Add av_d2str(). 2009-12-13 - r20826 - lavc 52.42.0 - AVStream  Add avg_frame_rate. 2009-12-12 - r20808 - lavu 50.6.0 - av_bmg_next()  Introduce the av_bmg_next() function. 2009-12-05 - r20734 - lavfi 1.12.0 - avfilter_draw_slice()  Add a slice_dir parameter to avfilter_draw_slice(). 2009-11-26 - r20611 - lavfi 1.11.0 - AVFilter  Remove the next field from AVFilter, this is not anymore required. 2009-11-25 - r20607 - lavfi 1.10.0 - avfilter_next()  Introduce the avfilter_next() function. 2009-11-25 - r20605 - lavfi 1.9.0 - avfilter_register()  Change the signature of avfilter_register() to make it return an  int. This is required since now the registration operation may fail. 2009-11-25 - r20603 - lavu 50.5.0 - pixdesc.h API  Make the pixdesc.h API public. 2009-10-27 - r20385 - lavfi 1.5.0 - AVFilter.next  Add a next field to AVFilter, this is used for simplifying the  registration and management of the registered filters. 2009-10-23 - r20356 - lavfi 1.4.1 - AVFilter.description  Add a description field to AVFilter. 2009-10-19 - r20302 - lavfi 1.3.0 - avfilter_make_format_list()  Change the interface of avfilter_make_format_list() from  avfilter_make_format_list(int n, ...) to  avfilter_make_format_list(enum PixelFormat *pix_fmts). 2009-10-18 - r20272 - lavfi 1.0.0 - avfilter_get_video_buffer()  Make avfilter_get_video_buffer() recursive and add the w and h  parameters to it. 2009-10-07 - r20189 - lavfi 0.5.1 - AVFilterPic  Added w and h fields to AVFilterPic. 2009-06-22 - r19250 - lavf 52.34.1 - AVFormatContext.packet_size  This is now an unsigned int instead of a signed int. 2009-06-19 - r19222 - lavc 52.32.0 - AVSubtitle.pts  Added a pts field to AVSubtitle which gives the subtitle's packet  PTS in AV_TIME_BASE. Some subtitle de-/encoders (e.g. XSUB) will  not work right without this. 2009-06-03 - r19078 - lavc 52.30.2 - AV_PKT_FLAG_KEY  PKT_FLAG_KEY has been deprecated and will be dropped for the next  major version. Use AV_PKT_FLAG_KEY instead. 2009-06-01 - r19025 - 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  the implements the AV_LOCK_* operations described in avcodec.h.  When the lock manager is registered FFmpeg is guaranteed to behave  correct also in a multi-threaded application. 2009-04-30 - r18719 - lavc 52.28.0 - av_free_packet  av_free_packet() is no longer an inline function. It is now exported. 2009-04-11 - r18431 - 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 - r18351 - 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 - r18321 - lavu 50.3.0 - av_fifo_space  Introduce the av_fifo_space() function. 2009-04-02 - r18317 - lavc 52.23.0 - AVPacket  Move AVPacket declaration from libavformat/avformat.h to  libavcodec/avcodec.h. 2009-03-22 - r18163 - lavu 50.2.0 - RGB32 pixel formats  Make the pixel formats: PIX_FMT_ARGB, PIX_FMT_RGBA, PIX_FMT_ABGR,  PIX_FMT_BGRA, which were defined as macros, defined as enum  PixelFormat values, and viceversa make PIX_FMT_RGB32,  PIX_FMT_RGB32_1, PIX_FMT_BGR32, PIX_FMT_BGR32_1 defined as macros.  Also make avcodec_get_pix_fmt() recognize the "rgb32" and "bgr32"  aliases.  Re-sort the enum PixelFormat list accordingly.  This change breaks API/ABI backward compatibility. 2009-03-22 - r18133 - 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 - r18116 - 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 - 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