APIchanges

Never assume the API of libav* to be stable unless at least 1 month has passed
since the last major version increase.

The last version increases were:
libavcodec:    2013-03-xx
libavdevice:   2013-03-xx
libavfilter:   2012-06-22
libavformat:   2013-03-xx
libavresample: 2012-10-05
libswscale:    2011-06-20
libavutil:     2012-10-22


API changes, most recent first:

2013-08-xx - xxxxxxx - lavc 55.12.0 - avcodec.h
  Deprecate the CODEC_CAP_HWACCEL_VDPAU codec capability. Use CODEC_CAP_HWACCEL
  and select the AV_PIX_FMT_VDPAU format with get_format() instead.

2013-08-xx - xxxxxxx - lavu 52.14.0 - pixfmt.h
  Deprecate AV_PIX_FMT_VDPAU_*. Use AV_PIX_FMT_VDPAU instead.

2013-08-xx - xxxxxxx - lavc 55.11.0 - avcodec.h
  Add output_picture_number to AVCodecParserContext.

2013-06-xx - xxxxxxx - lavc 55.10.0 - avcodec.h
  Add MPEG-2 AAC profiles

2013-06-xx - xxxxxxx - lavu 52.13.0 - mem.h
  Add av_realloc_array and av_reallocp_array

2013-05-xx - xxxxxxx - lavfi 3.10.0 - avfilter.h
  Add support for slice multithreading to lavfi. Filters supporting threading
  are marked with AVFILTER_FLAG_SLICE_THREADS.
  New fields AVFilterContext.thread_type, AVFilterGraph.thread_type and
  AVFilterGraph.nb_threads (accessible directly or through AVOptions) may be
  used to configure multithreading.

2013-xx-xx - xxxxxxx - lavu 52.12.0 - cpu.h
  Add av_cpu_count() function for getting the number of logical CPUs.

2013-05-xx - xxxxxxx - lavc 55.7.0 - avcodec.h
  Add picture_structure to AVCodecParserContext.

2013-05-xx - xxxxxxx - lavu 52.11.0 - pixdesc.h
  Replace PIX_FMT_* flags with AV_PIX_FMT_FLAG_*.

2013-04-xx - xxxxxxx - lavc 55.4.0 - avcodec.h
  Add field_order to AVCodecParserContext.

2013-03-xx - xxxxxxx - lavc 55.2.0 - avcodec.h
  Add CODEC_FLAG_UNALIGNED to allow decoders to produce unaligned output.

2013-04-11 - lavfi 3.8.0
  38f0c07 - Move all content from avfiltergraph.h to avfilter.h. Deprecate
            avfilterhraph.h, user applications should include just avfilter.h
  bc1a985 - Add avfilter_graph_alloc_filter(), deprecate avfilter_open() and
            avfilter_graph_add_filter().
  1113672 - Add AVFilterContext.graph pointing to the AVFilterGraph that contains the
            filter.
  48a5ada - Add avfilter_init_str(), deprecate avfilter_init_filter().
  1ba95a9 - Add avfilter_init_dict().
  7cdd737 - Add AVFilter.flags field and AVFILTER_FLAG_DYNAMIC_{INPUTS,OUTPUTS} flags.
  7e8fe4b - Add avfilter_pad_count() for counting filter inputs/outputs.
  fa2a34c - Add avfilter_next(), deprecate av_filter_next().
            Deprecate avfilter_uninit().

2013-04-09 - lavfi 3.7.0 - avfilter.h
  b439c99 - Add AVFilter.priv_class for exporting filter options through the
            AVOptions API in the similar way private options work in lavc and lavf.
  8114c10 - Add avfilter_get_class().
  Switch all filters to use AVOptions.

2013-03-19 - 2c328a9 - lavu 52.9.0 - pixdesc.h
  Add av_pix_fmt_count_planes() function for counting planes in a pixel format.

2013-03-16 - 42c7c61 - lavfi 3.6.0
  Add AVFilterGraph.nb_filters, deprecate AVFilterGraph.filter_count.

2013-03-08 - Reference counted buffers - lavu 52.8.0, lavc 55.0.0, lavf 55.0.0,
lavd 54.0.0, lavfi 3.5.0
  8e401db, 1cec062 - add a new API for reference counted buffers and buffer
                     pools (new header libavutil/buffer.h).
  1afddbe - add AVPacket.buf to allow reference counting for the AVPacket data.
            Add av_packet_from_data() function for constructing packets from
            av_malloc()ed data.
  7ecc2d4 - move AVFrame from lavc to lavu (new header libavutil/frame.h), add
            AVFrame.buf/extended_buf to allow reference counting for the AVFrame
            data. Add new API for working with reference-counted AVFrames.
  759001c - add the refcounted_frames field to AVCodecContext to make audio and
            video decoders return reference-counted frames. Add get_buffer2()
            callback to AVCodecContext which allocates reference-counted frames.
            Add avcodec_default_get_buffer2() as the default get_buffer2()
            implementation.
            Deprecate AVCodecContext.get_buffer() / release_buffer() /
            reget_buffer(), avcodec_default_get_buffer(),
            avcodec_default_reget_buffer(), avcodec_default_release_buffer().
            Remove avcodec_default_free_buffers(), which should not have ever
            been called from outside of lavc.
            Deprecate the following AVFrame fields:
                * base -- is now stored in AVBufferRef
                * reference, type, buffer_hints -- are unnecessary in the new API
                * hwaccel_picture_private, owner, thread_opaque -- should not
                  have been acessed from outside of lavc
                * qscale_table, qstride, qscale_type, mbskip_table, motion_val,
                  mb_type, dct_coeff, ref_index -- mpegvideo-specific tables,
                  which are not exported anymore.
  7e35037 - switch libavfilter to use AVFrame instead of AVFilterBufferRef. Add
            av_buffersrc_add_frame(), deprecate av_buffersrc_buffer().
            Add av_buffersink_get_frame() and av_buffersink_get_samples(),
            deprecate av_buffersink_read() and av_buffersink_read_samples().
            Deprecate AVFilterBufferRef and all functions for working with it.

2013-03-17 - 12c5c1d - lavu 52.8.0 - avstring.h
  Add av_isdigit, av_isgraph, av_isspace, av_isxdigit.

2013-02-23 - 9f12235 - lavfi 3.4.0 - avfiltergraph.h
  Add resample_lavr_opts to AVFilterGraph for setting libavresample options
  for auto-inserted resample filters.

2013-01-25 - 38c1466 - lavu 52.7.0 - dict.h
  Add av_dict_parse_string() to set multiple key/value pairs at once from a
  string.

2013-01-25 - b85a5e8 - lavu 52.6.0 - avstring.h
  Add av_strnstr()

2013-01-15 - 8ee288d - lavu 52.5.0 - hmac.h
  Add AVHMAC.

2013-01-13 - 44e065d - lavc 54.36.0 - vdpau.h
  Add AVVDPAUContext struct for VDPAU hardware-accelerated decoding.

2013-01-12 - 169fb94 - lavu 52.4.0 - pixdesc.h
  Add AV_PIX_FMT_VDPAU flag.

2013-01-07 - 074a00d - lavr 1.1.0
  Add avresample_set_channel_mapping() for input channel reordering,
  duplication, and silencing.

2012-12-29 - d8fd06c - lavu 52.3.0 - avstring.h
  Add av_basename() and av_dirname().

2012-11-11 - 5980f5d - lavu 52.2.0 - audioconvert.h
  Rename audioconvert.h to channel_layout.h. audioconvert.h is now deprecated.

2012-11-05 - dfde8a3 - lavu 52.1.0 - intmath.h
  Add av_ctz() for trailing zero bit count

2012-10-21 - a893655 - lavu 51.45.0 - error.h
  Add AVERROR_EXPERIMENTAL

2012-10-12 - d2fcb35 - lavu 51.44.0 - pixdesc.h
  Add functions for accessing pixel format descriptors.
  Accessing the av_pix_fmt_descriptors array directly is now
  deprecated.

2012-10-11 - 9a92aea - lavu 51.43.0 - aes.h, md5.h, sha.h, tree.h
  Add functions for allocating the opaque contexts for the algorithms,
  deprecate the context size variables.

2012-10-10 - b522000 - lavf 54.18.0 - avio.h
  Add avio_closep to complement avio_close.

2012-10-08 - 78071a1 - lavu 51.42.0 - pixfmt.h
  Rename PixelFormat to AVPixelFormat and all PIX_FMT_* to AV_PIX_FMT_*.
  To provide backwards compatibility, PixelFormat is now #defined as
  AVPixelFormat.
  Note that this can break user code that includes pixfmt.h and uses the
  'PixelFormat' identifier. Such code should either #undef PixelFormat
  or stop using the PixelFormat name.

2012-10-05 - e7ba5b1 - lavr 1.0.0 - avresample.h
  Data planes parameters to avresample_convert() and
  avresample_read() are now uint8_t** instead of void**.
  Libavresample is now stable.

2012-09-24 - a42aada - lavc 54.28.0 - avcodec.h
  Add avcodec_free_frame(). This function must now
  be used for freeing an AVFrame.

2012-09-12 - 8919fee - lavu 51.41.0 - audioconvert.h
  Added AV_CH_LOW_FREQUENCY_2 channel mask value.

2012-09-04 - 686a329 - lavu 51.40.0 - opt.h
  Reordered the fields in default_val in AVOption, changed which
  default_val field is used for which AVOptionType.

2012-08-30 - a231832 - lavc 54.26.1 - avcodec.h
  Add codec descriptor properties AV_CODEC_PROP_LOSSY and
  AV_CODEC_PROP_LOSSLESS.

2012-08-18 - lavc 54.26 - avcodec.h
  Add codec descriptors for accessing codec properties without having
  to refer to a specific decoder or encoder.

  c223d79 - Add an AVCodecDescriptor struct and functions
            avcodec_descriptor_get() and avcodec_descriptor_next().
  51efed1 - Add AVCodecDescriptor.props and AV_CODEC_PROP_INTRA_ONLY.
  91e59fe - Add avcodec_descriptor_get_by_name().