What is AI B-Roll?

B-roll is secondary footage that plays over narration to illustrate what the speaker is discussing. Traditionally, B-roll was filmed or sourced from stock libraries. AI B-roll uses text-to-video or image-to-video models to generate custom footage from scene descriptions. This gives creators exact visual matches for their narration rather than settling for approximate stock footage. AI B-roll is particularly powerful for faceless videos, educational content, and marketing videos where custom visuals would otherwise require expensive production. BlitzReels automatically generates AI B-roll from script segments, matching each scene's text with contextually relevant AI-generated video clips.