I have a bunch of (almost lossless) 3d game screencasts which now occupy considerable amount of my hdd space. I would like to reduce their size. Overall image quality isn't of great concern, except for readability of text (player nicknames etc), which is layed over the 3d scene. Encoding speed doesn't matter much either.
I've tried using x264; unfortunately, when decreasing quality parameters (-crf or -qp) the texts quickly become unreadable (while there's still much room for overall quality degradation).
Are there any special codecs for such a situation; or maybe recommendation on tuning x264? Or any other solutions.
Some details: original videos are 1680x996 encoded using x264 ultrafast, crf 25, fps 15 (~7Mbps). The best (smallest in size while still readable texts) I get from x264 is with qp 27 "slower" preset (~2.7 Mbps, difference between slower and medium is negligible). I use ffmpeg packaged with ubuntu 13.04 for both capturing and reencoding.