README: Fix descriptions of seek threshold.
lwlibav: Determine field dominance by flags in source file.
README: Update for the previous commit.
lsmashsource: LWLibavVideoSource() supports getting the parity of each frame.
Merge branch 'plain' into build-msvc

Conflicts:
	AviUtl/lwinput.c
	common/lwindex.c
lsmashsource: Support planar YUV4:2:0 high bit-depth (9,10,16) by MSB/LSB interleaved fake.
lsmashsource: Support direct rendering for planar YUV4:2:0 high bit-depth (9,10,16).
lsmashsource: Add more colorformats to the header.

These are available under AviSynth 2.6 or later.
lsmashsource: Support planar YUV4:2:2 high bit-depth (9,10,16) by MSB/LSB interleaved fake.

This feature requires AviSynth 2.6 or later.
lsmashsource: Support planar YUV 4:4:4 (YV24).

Available under Avisynth 2.6 or later.
lsmashsource: Support planar YUV4:4:4 high bit-depth (9,10,16) by MSB/LSB interleaved fake.

This feature requires AviSynth 2.6 or later.
lsmashsource: Support planar YUV 4:1:0 and 4:1:1.

Available under Avisynth 2.6 or later.
lsmashsource: Support 8bit gray-scale (planar YUV 4:0:0).
common/video_output: Set SWS_BITEXACT for more accurate YUV->RGB conversion.
lsmashsource: Add 'stacked' option to output as stacked format for high bit-depth.
lsmashsource: Add 'format' option to force output pixel format.

Currently, the following formats are supported.
  YUV420P8
  YUV422P8
  YUV444P8
  YUV410P8
  YUV411P8
  YUV420P9
  YUV422P9
  YUV444P9
  YUV420P10
  YUV422P10
  YUV444P10
  YUV420P16
  YUV422P16
  YUV444P16
lsmashsource: Map BGR24/RGB24 (input) to BGR24 (output).

Add "RGB24" to the list of 'format'.
lsmashsource: Add "YUY2" to the list of "format".
lsmashsource: Fix typo in LSMASH*Source.

Fix direct rendering won't be enabled.
Stacked format was enabled instead.
lsmashsource: Support output of some little endianness 12 and 14 bit YUV formats.

Available only when ffmpeg libavutil and swscale are linked.