The phrase "the video was in boomerang form" is grammatically correct, but its meaning may depend on context. If you are referring to a video that plays in a loop, mimicking the action of a boomerang, it conveys the idea clearly. However, if "boomerang form" is not commonly understood in the context you’re using, you might consider rephrasing it for clarity. For example:
- "The video looped back and forth like a boomerang."
- "The video was