Transparent video formats explained: MOV vs WEBM vs green screen

What 'transparent video' means

A normal video stores a colour for every pixel. A transparent video also stores an alpha channel — a value for every pixel saying how see-through it is, from fully solid to fully invisible, with every step in between. That 'in between' matters: it's what lets a glow fade softly into your footage or a shadow sit naturally on top of it. Only some video formats can store an alpha channel, and only some apps can read it.

MOV (ProRes 4444): the editing master

ProRes 4444 is a professional video codec from Apple that stores full colour detail plus an alpha channel. Editing software is built to handle it: Premiere Pro, Final Cut Pro, DaVinci Resolve, After Effects and CapCut desktop all read its transparency, and OBS Studio plays it too. The downside is size — ProRes files are many times bigger than a .webm of the same clip, which is why you shouldn't upload one to a browser-based tool. Our MOVs are 10-bit ProRes 4444 with alpha.

Windows can't preview ProRes in the Photos app, and many players show the transparent areas as black. That's normal. Drag the file into your editor or OBS and the transparency is there.

WEBM: the streaming file

WEBM is a web video format. Using the VP8 or VP9 codecs it can carry an alpha channel at a tiny fraction of ProRes's size, and on stream it looks the same. Chrome, Edge, Firefox and anything built on them play transparent WEBM — which includes OBS browser sources, TikTok LIVE Studio, Streamlabs Desktop, TikFinity overlays and Streamlabs and StreamElements alert widgets. Safari's support for transparent WEBM is patchy, so don't judge a WEBM by how it looks in Safari.

Green screen MP4: the backup

A standard MP4 (H.264) has no alpha channel. Instead, the animation sits on a flat green background that you remove with a chroma key effect. It plays everywhere, which is why it's included — but keying is never perfect. Fine edges can keep a green fringe, soft glows and shadows can't be reproduced properly, and anything green in the design gets removed along with the background. Use it only when an app can't read the other two.

Which file to use where

1. CapCut (desktop): the transparent .mov — drop it on a track above your video, no chroma key needed.
2. CapCut (phone): the .mov, or the .webm if your phone struggles with the larger file.
3. Premiere Pro, Final Cut Pro, DaVinci Resolve, After Effects: the .mov.
4. VEGAS Pro: the .mov, then set the clip's alpha channel to 'Straight' in its media properties.
5. OBS Studio and Streamlabs Desktop media sources: either — the .webm is lighter on your PC during a stream.
6. TikTok LIVE Studio: the .webm.
7. Streamlabs and StreamElements alerts, TikFinity and any browser-based tool: the .webm only.
8. Any app with no transparency support: the green screen .mp4 with a chroma key.

How transparency gets lost

1. Sending the file through WhatsApp, Messenger or similar apps: they re-compress video to a normal MP4 and the alpha channel is thrown away. Download the file directly on the device you'll use, or move it as a file via cloud storage or a cable.
2. Re-exporting it as an MP4 'to make it smaller': H.264 MP4 has nowhere to store transparency, so the background becomes solid black.
3. Opening it in a phone's gallery and saving a 'copy': some galleries re-encode on save.
4. Uploading a .mov to a browser tool: browsers don't play ProRes, so you'll see nothing at all.
5. Using the green screen file and forgetting the chroma key: a big green box over your video.

A note on dark edges

Transparent video stores alpha in one of two ways: 'straight' or 'premultiplied'. If an app assumes the wrong one, you'll see a thin dark or bright halo around the graphic. Most editors detect it automatically. If you see a halo, look for an alpha setting in the clip's properties (DaVinci Resolve: Clip Attributes → Alpha Mode; VEGAS Pro: Media properties → Alpha channel) and try the other option.