Four thugs were convicted of a Lower East Side gang assault yesterday, thanks to video of the attack.

“The first time you see it, it was very disturbing,” alternate juror Diane Doty, 48, said after the verdict in Manhattan Supreme Court.

Kyam Washington, 37, was bashed in the head during the May 2010 melee.

Martrell Tyrell, 22, now faces up to 25 years in prison for first-degree gang assault and first-degree assault. Co-defendants Shadia Brackman, 22, Andrew McCray, 21, and Christopher Montanez, 28, face up to 15 years for second-degree gang assault and second-degree assault.