APIchanges

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

The last version increases were:
libavcodec:    2015-08-28
libavdevice:   2015-08-28
libavfilter:   2015-08-28
libavformat:   2015-08-28
libavresample: 2015-08-28
libpostproc:   2015-08-28
libswresample: 2015-08-28
libswscale:    2015-08-28
libavutil:     2015-08-28


API changes, most recent first:

2016-xx-xx - xxxxxxx - lavc 57.61.100 / lavc 57.24.0 - avcodec.h
  Decoders now export the frame timestamp as AVFrame.pts. It was
  previously exported as AVFrame.pkt_pts, which is now deprecated.

  Note: When decoding, AVFrame.pts uses the stream/packet timebase,
  and not the codec timebase.

2016-09-xx - xxxxxxx - lavu 55.32.100 / 55.16.0 - hwcontext.h hwcontext_qsv.h
  Add AV_HWDEVICE_TYPE_QSV and a new installed header with QSV-specific
  hwcontext definitions.

2016-09-xx - xxxxxxx - lavc 57.59.100/ 57.23.0 - avcodec.h
  AVCodecContext.hw_frames_ctx now may be used by decoders.

2016-09-27 - xxxxxxx - lavf 57.51.100 - avformat.h
  Add av_stream_get_codec_timebase()

2016-09-27 - 23c0779 - lswr 2.2.100 - swresample.h
  Add swr_build_matrix().

2016-09-xx - xxxxxxx - lavc 57.58.100 - avcodec.h
  Add AV_CODEC_CAP_AVOID_PROBING codec capability flag.

2016-09-xx - xxxxxxx - lavf 57.49.100 - avformat.h
  Add avformat_transfer_internal_stream_timing_info helper to help with stream
  copy.

2016-08-29 - 4493390 - lavfi 6.58.100 - avfilter.h
  Add AVFilterContext.nb_threads.

2016-08-15 - c3c4c72 - lavc 57.53.100 - avcodec.h
  Add trailing_padding to AVCodecContext to match the corresponding
  field in AVCodecParameters.

2016-08-15 - b746ed7 - lavc 57.52.100 - avcodec.h
  Add a new API for chained BSF filters and passthrough (null) BSF --
  av_bsf_list_alloc(), av_bsf_list_free(), av_bsf_list_append(),
  av_bsf_list_append2(), av_bsf_list_finalize(), av_bsf_list_parse_str()
  and av_bsf_get_null_filter().

2016-08-04 - 82a33c8 - lavf 57.46.100 - avformat.h
  Add av_get_frame_filename2()

2016-07-09 - 775389f / 90f469a - lavc 57.50.100 / 57.20.0 - avcodec.h
  Add FF_PROFILE_H264_MULTIVIEW_HIGH and FF_PROFILE_H264_STEREO_HIGH.

2016-06-30 - c1c7e0ab - lavf 57.41.100 - avformat.h
  Moved codecpar field from AVStream to the end of the struct, so that
  the following private fields are in the same location as in FFmpeg 3.0 (lavf 57.25.100).

2016-06-30 - 042fb69d - lavu 55.28.100 - frame.h
  Moved hw_frames_ctx field from AVFrame to the end of the struct, so that
  the following private fields are in the same location as in FFmpeg 3.0 (lavu 55.17.103).

2016-06-29 - 1a751455 - lavfi 6.47.100 - avfilter.h
  Fix accidental ABI breakage in AVFilterContext.
  ABI was broken in 8688d3a, lavfi 6.42.100 and released as ffmpeg 3.1.

  Because of this, ffmpeg and ffplay built against lavfi>=6.42.100 will not be
  compatible with lavfi>=6.47.100. Potentially also affects other users of
  libavfilter if they are using one of the affected fields.

-------- 8< --------- FFmpeg 3.1 was cut here -------- 8< ---------

2016-06-26 - 481f320 / 1c9e861 - lavu 55.27.100 / 55.13.0 - hwcontext.h
  Add av_hwdevice_ctx_create().

2016-06-26 - b95534b / e47b8bb - lavc 57.48.101 / 57.19.1 - avcodec.h
  Adjust values for JPEG 2000 profiles.

2016-06-23 - 5d75e46 / db7968b - lavf 57.40.100 / 57.7.0 - avio.h
  Add AVIODataMarkerType, write_data_type, ignore_boundary_point and
  avio_write_marker.

2016-06-23 - abb3cc4 / 0c4468d - lavu 55.26.100 / 55.12.0 - opt.h
  Add av_stereo3d_type_name() and av_stereo3d_from_name().

2016-06-22 - 3689efe / c46db38 - lavu 55.25.100 / 55.11.0 - hwcontext_dxva2.h
  Add new installed header with DXVA2-specific hwcontext definitions.

2016-04-27 - fb91871 - lavu 55.23.100 - log.h
  Add a new function av_log_format_line2() which returns number of bytes
  written to the target buffer.

2016-04-21 - 7fc329e - lavc 57.37.100 - avcodec.h
  Add a new audio/video encoding and decoding API with decoupled input
  and output -- avcodec_send_packet(), avcodec_receive_frame(),
  avcodec_send_frame() and avcodec_receive_packet().

2016-04-17 - af9cac1 / 33d1898 - lavc 57.35.100 / 57.15.0 - avcodec.h
  Add a new bitstream filtering API working with AVPackets.
  Deprecate the old bitstream filtering API.

2016-04-14 - 8688d3a / 07a844f - lavfi 6.42.100 / 6.3.0 - avfilter.h
  Add AVFilterContext.hw_device_ctx.

2016-04-14 - 28abb21 / 551c677 - lavu 55.22.100 / 55.9.0 - hwcontext_vaapi.h
  Add new installed header with VAAPI-specific hwcontext definitions.

2016-04-14 - afccfaf / b1f01e8 - lavu 55.21.100 / 55.7.0 - hwcontext.h
  Add AVHWFramesConstraints and associated API.

2016-04-11 - 6f69f7a / 9200514 - lavf 57.33.100 / 57.5.0 - avformat.h
  Add AVStream.codecpar, deprecate AVStream.codec.

2016-04-02 - e8a9b64 - lavu 55.20.100 - base64.h
  Add AV_BASE64_DECODE_SIZE(x) macro.

2016-xx-xx - lavc 57.33.100 / 57.14.0 - avcodec.h
  f9b1cf1 / 998e1b8 - Add AVCodecParameters and its related API.
  e6053b3 / a806834 - Add av_get_audio_frame_duration2().

2016-03-11 - 6d8ab35 - lavf/lavc 57.28.101
  Add requirement to bitstream filtering API that returned packets with
  size == 0 and side_data_elems == 0 are to be skipped by the caller.

2016-03-04 - 9362973 - lavf 57.28.100
  Add protocol blacklisting API

2016-02-28 - 4dd4d53 - lavc 57.27.101
  Validate AVFrame returned by get_buffer2 to have required
  planes not NULL and unused planes set to NULL as crashes
  and buffer overflow are possible with certain streams if
  that is not the case.

2016-02-26 - 30e7685 - lavc 57.27.100 - avcodec.h
  "flags2" decoding option now allows the flag "ass_ro_flush_noop" preventing
  the reset of the ASS ReadOrder field on flush. This affects the content of
  AVSubtitles.rects[N]->ass when "sub_text_format" is set to "ass" (see
  previous entry).

2016-02-26 - 2941282 - lavc 57.26.100 - avcodec.h
  Add a "sub_text_format" subtitles decoding option allowing the values "ass"
  (recommended) and "ass_with_timings" (not recommended, deprecated, default).
  The default value for this option will change to "ass" at the next major
  libavcodec version bump.

  The current default is "ass_with_timings" for compatibility. This means that
  all subtitles text decoders currently still output ASS with timings printed
  as strings in the AVSubtitles.rects[N]->ass fields.

  Setting "sub_text_format" to "ass" allows a better timing accuracy (ASS
  timing is limited to a 1/100 time base, so this is relevant for any subtitles
  format needing a bigger one), ease timing adjustments, and prevents the need
  of removing the timing from the decoded string yourself. This form is also
  known as "the Matroska form". The timing information (start time, duration)
  can be found in the AVSubtitles fields.

2016-02-24 - 7e49cdd / 7b3214d0 - lavc 57.25.100 / 57.13.0 - avcodec.h
  Add AVCodecContext.hw_frames_ctx.

2016-02-24 - 1042402 / b3dd30d - lavfi 6.36.100 / 6.2.0 - avfilter.h
  avfilter.h - Add AVFilterLink.hw_frames_ctx.
  buffersrc.h - Add AVBufferSrcParameters and functions for handling it.

2016-02-23 - 14f7a3d - lavc 57.25.100
  Add AV_PKT_DATA_MPEGTS_STREAM_ID for exporting the MPEGTS stream ID.

2016-02-18 - 08acab8 - lavu 55.18.100 - audio_fifo.h
  Add av_audio_fifo_peek_at().

2016-xx-xx - lavu 55.18.100 / 55.6.0
  26abd51 / 721a4ef buffer.h - Add av_buffer_pool_init2().
  1a70878 / 89923e4 hwcontext.h - Add a new installed header hwcontext.h with a new API
                        for handling hwaccel frames.
  6992276 / ad884d1 hwcontext_cuda.h - Add a new installed header hwcontext_cuda.h with
                             CUDA-specific hwcontext definitions.
  d779d8d / a001ce3 hwcontext_vdpau.h - Add a new installed header hwcontext_vdpau.h with
                              VDPAU-specific hwcontext definitions.
  63c3e35 / 7bc780c pixfmt.h - Add AV_PIX_FMT_CUDA.

-------- 8< --------- FFmpeg 3.0 was cut here -------- 8< ---------

2016-02-10 - bc9a596 / 9f61abc - lavf 57.25.100 / 57.3.0 - avformat.h
  Add AVFormatContext.opaque, io_open and io_close, allowing custom IO

2016-02-01 - 1dba837 - lavf 57.24.100 - avformat.h, avio.h
  Add protocol_whitelist to AVFormatContext, AVIOContext

2016-01-31 - 66e9d2f - lavu 55.17.100 - frame.h
  Add AV_FRAME_DATA_GOP_TIMECODE for exporting MPEG1/2 GOP timecodes.

2016-01-01 - 5e8b053 / 2c68113 - lavc 57.21.100 / 57.12.0 - avcodec.h