Lossless video capture

[goose]

New feature that allows capturing VM activity to video file is indeed great. But I can't find an option to turn off lossy compression. If I just turn quality to maximum level, there are still artifacts in resulting video.
If the video doesn't contain photorealistic things (static images like wallpapers on desktop don't count), using lossless video codec will be more efficient and give perfect quality at the same time.
And compression doesn't matter much, because user can do anything with video after recording to minimize the size. But there is no way to restore lost information from lossy-encoded video. So some simple codec will be fine, as long as it has lossless mode of operation and support of RGB888 color space.

[vatoloco]

I second this suggestion.
There are some free/open source lossless codecs out there, like Lagarith or CamStudio (less known lossless codec, but in my experience it produces the smallest files).

I usually use CamStudio or OBS for screen recording, but for recording a Virtualboxed guest OS they both have a problem: if 3D acceleration is enabled for the guest I can't record full screen, it just produces a black picture. (If someone knows a solution let me know).

[Perryg]

The problem being they need to be open source and not commercial.

[vatoloco]

Lagarith is open source (GPL).

CamStudio (the program) is open source too. Its lossless codec is probably open source as well, but I couldn't find any reliable info.

[vatoloco]

Just wanted to add, in case this gets implemented, it's good to choose an appropriate codec, because lossless codecs vary a lot in terms of compression, some are much more optimized for desktop screen recording than others.
Here's a recent discussion on doom9.

BTW, it seems that open source is the rule rather than the exception, when it comes to lossless codecs.

[michaln]

Lagarith is open source (GPL).

'GPL' and 'open source' are different things. We'd need a codec with a license less restrictive than GPL to even consider it. See the VP8 codec for an example (it uses a BSD license).