What is B-roll?

Where the name comes from

In film editing, two rolls of film were once assembled in parallel. The A-roll carried the main shots and the B-roll carried the cutaways, so the editor could switch between them. The terms stuck long after film. Today A-roll usually means interviews, presenters or the main action, and B-roll means everything that illustrates it.

What B-roll is used for

• Showing, not telling. An interviewee describes a factory; you see the factory.
• Hiding edits. Cutting an interview answer leaves a jump in the picture. Laying B-roll over the cut hides it while the audio flows.
• Pacing. Cutaways give long talking segments some rhythm.
• Context and mood. Establishing shots, details and atmosphere tell the viewer where they are.

A concrete example

A 90-second product video might open on the founder talking (A-roll). When she mentions the workshop, the edit cuts to a wide shot of the workshop, then a close-up of tools, then back to her. Those two shots are B-roll. Her audio keeps playing the whole time, so the viewer hears one continuous thought.

Good B-roll is usually shot on purpose: a mix of wide, medium and close shots of the same subject, held for several seconds each so the editor has room to trim. Many crews also grab general cutaways at every location, such as exteriors, hands, signs and crowds, because it is much cheaper to shoot them on the day than to go back.

The hard part: finding it

Shooting B-roll is easy; finding the right clip months later is not. Libraries grow to thousands of short clips with names like C0042.MP4. Editors cope in a few ways: careful folder structures, keywording clips at ingest, contact sheets, or simply scrubbing. All of them depend on someone having tagged the footage in advance, which rarely happens on tight projects.

Visual search changes this. If software can describe what is in each frame, you can search for “close-up of hands on a keyboard” or “aerial shot of a coastline” without anyone having tagged anything. Transcripts help too, when the B-roll has natural sound or someone mentions the location.

In MediaFind

MediaFind indexes keyframes of your video on your computer, so you can find B-roll by describing what's on screen, by color and mood, by on-screen text, or with a sample image. Results jump to the exact timestamp. With Pro, you can export your selects as an FCPXML or EDL timeline for Premiere Pro, DaVinci Resolve or Final Cut Pro. Read how to find B-roll by description or the B-roll search write-up.

Frequently asked questions

What is the difference between A-roll and B-roll?

A-roll is the main footage that carries the story, usually an interview or presenter. B-roll is the supporting footage cut over it to illustrate or cover edits.

Does B-roll have sound?

It can. B-roll often keeps its natural sound at a low level under the main audio, which makes cutaways feel less abrupt.

How do I organize a large B-roll library?

Consistent folders and keywords help, but they depend on tagging at ingest. Visual search tools can find shots by description without any manual tags.