David wrote:Why is it that PoP videos are usually bigger with the lossy OGG Theora codec than with the lossless ZMBV codec?
I'm not familiar enough with the subject matter to give you an insightful answer, but here are my thoughts. The lossless stream is a recording, while the lossy stream comes from the output of a converter. This means you need to take into account at least these two things: 1. if the game footage was directly captured to Theora, the file size might be smaller, and 2. I used "-v 10" video quality when converting with ffmpeg2theora, which is the highest encoding quality (the default is 6) and presumably makes the output as non-lossy as possible. Also, it does seem that ZMBV (heavily?) uses previous frames
, and lossless PoP1 footage includes almost no pixels that change. Even moving to another room is probably just one frame, which is usually still not a full redraw given the similarity of many rooms and tiles. Theora's algorithm discrete cosine transform
may be less suitable to process such footage. Just some speculation.