Thank you Reel.Deel
I made several tests comparing the result of different filters.
Source clips:
source_bubbles,
source_carnival,
source_cat
My comparison result of grayworld,
GamMac and
AWB filters:
Video comparison:
test_bubbles,
test_carnival,
test_cat
It is difficult to compare which filter is better. I think, when the colors are heavily distorted, then grayworld gives better results, and when the colors are almost normal, then the result is worse.