Efficient way to compare output

[juGGaKNot]

Input :

ID : 0
Format : RGBA
Codec ID : 0x00000000
Codec ID/Info : Basic Windows bitmap format. 1, 4 and 8 bpp versions are palettised. 16, 24 and 32bpp contain raw RGB samples
Duration : 15s 42ms
Bit rate : 453 Mbps
Width : 1 024 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 24.000 fps
Bit depth : 8 bits
Bits/(Pixel*Frame) : 31.999
Stream size : 812 MiB (100%)

I use latest vlc to play the 4:4:4 video ( and capture screens )

How can i capture the same frame from all 3 videos ? ( original, 4:2:0 and 4:4:4 video ) ?

x264 encodes have same cmd, the 4:4:4 one has extra

--demuxer lavf --output-csp i444