WebM

WebM (.webm) is a video file format developed by  Google. WebM was originally designed to be used on webpages to save bandwidth, but it also has some benefits when it comes to video games and many other applications.

The biggest benefit of WebM over Bink (or AVI) for games is that of file size; a WebM video will be significantly smaller than that of a similar-quality Bink file. For example, the installation size of Hunt Down the Freeman decreased by 5.7 GB when switching its FMV cutscenes from Bink to WebM^[1]. Furthermore, WebM is much more common and easier to make than the Bink file format, as Bink requires a tool that only takes AVI, then only to find out there's audio or video sync issues that may sometimes happen.

WebM is supported in the following games, engines, and engine branches:

	Video codecs			Audio codecs
Implementation	VP8	VP9	AV1	Vorbis	Opus
Source 2	?	?	?	?	?
GoldSrc (since 25th anniversary update; intro video only)	Yes	Yes	No	Yes*	No
Counter-Strike: Global Offensive (since 2018 Panorama update)	?	?	?	?	?
Team Fortress 2 (x64_test branch)	Yes	Yes	No	Yes	No
Strata Source	?	?	?	?	?
WebM Video Services for (used by Hunt Down the Freeman)	Yes	Yes	No	Yes	Yes

*Audio is read, but muted. <moddir>/sound/ui/valve_sound.wav is used instead.

References

References
1. Hunt Down The Freeman - July blog: where we're at + looking for team members! - Steam News Bink video is replaced with webm (like CSGO and Source 2) and has successfully freed up 5.7GB of space .

External links

•  WebM on Wikipedia