[FFmpeg-user] a -vf for broadcast safe

[Dave Rice]

> On Feb 12, 2014, at 4:43 AM, Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:
> 
> Jim Shupert <jshupert <at> pps-inc.com> writes:
> 
>> input a unCompressed  yuv avi and get a second 
>> Uncompressed yuv avi or mov and it would be 
>> 'broadcast safe'.
> 
> Rereading your original post:
> Could you provide an uncompressed yuv avi that 
> needs the filter you have in mind?
> (One frame is probably enough.)

Responding late, as I find myself in need of this filter as well.

A sample that needs the filter can be generated via:

ffmpeg -f lavfi -i color=gray:s=256x256 -vf format=yuv444p,geq=lum=X,scale=out_range=tv -vframes 1 -pix_fmt yuv444p -c:v rawvideo -y needsbroadcastsafe.nut
ffmpeg version 2.8.4 Copyright (c) 2000-2015 the FFmpeg developers
  built with Apple LLVM version 7.0.2 (clang-700.1.81)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/2.8.4 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-opencl --enable-libx264 --enable-libmp3lame --enable-libvo-aacenc --enable-libxvid --enable-libfreetype --enable-libfaac --enable-libass --enable-ffplay --enable-libopenjpeg --disable-decoder=jpeg2000 --extra-cflags=-I/usr/local/Cellar/openjpeg/1.5.2_1/include/openjpeg-1.5 --enable-nonfree --enable-vda
  libavutil      54. 31.100 / 54. 31.100
  libavcodec     56. 60.100 / 56. 60.100
  libavformat    56. 40.101 / 56. 40.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 40.101 /  5. 40.101
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.101 /  1.  2.101
  libpostproc    53.  3.100 / 53.  3.100
Input #0, lavfi, from 'color=gray:s=256x256':
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 256x256 [SAR 1:1 DAR 1:1], 25 tbr, 25 tbn, 25 tbc
Output #0, nut, to 'needsbroadcastsafe.nut':
  Metadata:
    encoder         : Lavf56.40.101
    Stream #0:0: Video: rawvideo (444P / 0x50343434), yuv444p, 256x256 [SAR 1:1 DAR 1:1], q=2-31, 200 kb/s, 25 fps, 51200 tbn, 25 tbc
    Metadata:
      encoder         : Lavc56.60.100 rawvideo
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo (native) -> rawvideo (native))
Press [q] to stop, [?] for help
frame=    1 fps=0.0 q=-0.0 Lsize=     192kB time=00:00:00.04 bitrate=39382.2kbits/s    
video:192kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.154114%

The result of `ffmpeg -i needsbroadcastsafe.nut -vf broadcastsafe nowbroadcastsafe.nut` would result in the output containing luma values only between 16-235 inclusively (8 bit) and 16-240 for chroma planes.
Dave Rice