Removing the background from an image is relatively straightforward today. Upload an image, run a segmentation model, and export a transparent PNG.

But video is a different problem.

Even if you manage to remove the background from every frame, you still have to deal with temporal consistency, encoding, alpha channels, audio, and compatibility across video editors and browsers.

I've been exploring these problems while working on a browser-based video background removal tool.

Here are some practical things worth knowing.

1. Background removal is not the same as transparency

This is probably the most confusing part.

When you remove an image background, you can export a PNG with an alpha channel.

For video, it depends on the codec and container format.

For example:

MP4 (H.264): Widely compatible, but doesn't support alpha transparency in the standard H.264 workflow.

WebM (VP9 with alpha): Useful for transparent video on supported browsers.

ProRes 4444 MOV: Supports alpha channels and works well for…