Lossless screen-recording software For a small project of mine I want to record short screen-casts which show features of my program. Currently, I'm using a small app on my Ubuntu box which creates directly animated gif output. The drawback is, that gif has some limitations in the number of colors. If you inspect some of the gifs you may note that although it looks great, it's not perfect, especially when you look at the aliased fonts



There are some handmade solutions, for instance the demonstration on the sublime-text site. To have something that nice, you first need to record your screen completely lossless. Most screen-casting programs I know unfortunately do compress the video.

Question: I have Ubuntu and OSX at my disposal, what (if possible free) screen-casting solutions exists which let me create lossless videos?

Extra credit for programs where I can select the region or window to record and turn off audio.

Update

To make it clear what I mean with lossless: Usually, videos are compressed with a method which is perfect for natural images/videos but horrible for images/videos having sharp edges and one-colored structures. I made two screen-casts and zoomed a small part so that those effects are visible. The first one is done with gtk-recordmydesktop with highest quality and the artifacts in the gray area are clearly visible



The second one is done with the small Record your Desktop tool which saves gif files directly and takes the exact pixels of the screen without compression.



What I want is a screen-caster which saves its videos in this raw format without the limitations of gif.

Possibly related questions:


How does Salman Khan make his screencasts?
creating a lossless mp4 screencast
FFmpeg with a lossless codec is one solution. I recall a comparison of different codecs which concluded that Apple Animation (known to ffmpeg as qtrle) gave the best quality for screen-recording.

ffmpeg -f x11grab -r 25 -s 1024x768 -i :0.0 -c:v qtrle output.mov


Stop it by opening its terminal while it is running and pressing q. Obviously change the resolution (1024x768 here) to match your own. For selecting a section of your screen, see how to grab the screen on the ffmpeg wiki.

It is possible that the ffmpeg which comes with your Linux distribution does not have the qtrle codec included. In this case you have to download and compile your own version.