Applying colorkey twice in FFMpeg

Question

I have a video with green screen. Unfortunately there is a shadow on the green screen. Increasing the tolerance got side effects. Thus I thought of the obvious, just apply colorkey twice.

I tried this, but it only applies the last colorkey. If I switch the two colorkeys then it either removes the shadowed area or the light area.

ffmpeg -i bacground.jpg -i green.mp4 -filter_complex '[1:v]colorkey=0x32AB57:0.25:[ckout1];[ckout1]colorkey=0x016733:0.2:[ckout];[0:v][ckout]overlay[out]' -map '[out]' -map '1:a:?' -y output.mp4

What Am I doing wrong here?

Answer 1

You could apply the colorkey to the input twice then blend the alpha channels

-filter_complex "[1:v]colorkey=0x32AB57:0.25[ck1];[1:v]colorkey=0x016733:0.2[ck2];[ck1][ck2]blend=c3_mode=and"