crop script for fixed height and width for encoder

[omricarmi]

use ffmpeg to create script that crop yuv encoder input to width and height that are complete division of the base size unit, example : 4x4.

[omricarmi]

@harelnh after you finish do it manually copy here please the bash lines you have used with ffmpeg

[harelnh]

@omricarmi here is the command i finally used :
ffmpeg - video_size 854x480 -r 30 -pixel_format yuv420p -i basketball_big_854x480_30.yuv -filter:v "crop=852:480:0:0" basketball_long_cropped_852x480_30.yuv

[omricarmi]

reminder for my self: make sure that after we crop the video change its cfg file in correspond.