TMZ- Baby Bash fans can chill -- despite a video making it seem like he got pinched for smoking a joint, right in front of a cop ... there was no funny biz. Just show biz.

Baby tells TMZ he got hit up left and right by fans who'd seen him getting patted down Tuesday night by an officer in L.A. -- but he assures us the scene they saw was all for a music video.

He says he was shooting a scene outside a dispensary for his new song, "Hey Rasta." Gotta love the plot -- a cop searches and arrests him for lighting up in front of 5-0. Baby's response is the best ... "It's just a little herb, Mr. Officer."

Hand that man an Oscar-shaped bong!