Re: HOWTO: Proper Screencasting on Linux
You can encode to the new open format "WebM", which should give you much better quality than .ogg with Theora. Just replace libtheora with libvpx (assuming you followed the ffmpeg building guide, you should have that included as well) and encode the file in 2 passes with the -pass 1/2 option. Also, change the extension to .webm instead of .ogg.
ffmpeg -i output.mkv -an -vcodec libvpx -b 1000k -pass 1 our-final-product.webm
Change the bitrate (-b 1000k) to control the size/quality tradeoff. Also, change the number of threads (-threads 2) to suit the number of threads your CPU has. If your CPU is not multi-threaded, you can omit the -threads option completely. If you have a modern web browser, you can open the file and play it natively inside it. A WebM file consists of VP8 video and Vorbis audio mulitplexed into a .webm container (which is basically a subset of the Matroska container, aka .mkv).
ffmpeg -i output.mkv -acodec libvorbis -ab 128k -ac 2 -vcodec libvpx -b 1000k -threads 2 -pass 2 our-final-product.webm
Last edited by verb3k; March 26th, 2011 at 11:08 PM.
Reason: Better commands
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