LVF (lossless video file) is a very simple and speed lossless video format specially created to work with bitmap output of 3DSMax(R)-like renderers, and store the high definition output in the form of one lossless compressed large videofile. User can easy split and merge these files without any information loss on a very high speed. Even if you need just one frame you'll got it with one move with original rendered quality.
Kumaji is an advanced subtitle rendering library aiming for complete cross-platform support, complete and compliant support for all common subtitle formats and, of course, speed. The source code is also intended to be easy to understand and hack at.