Quote:
Originally Posted by Jellygoose
I guess I missed that page in the "Crap" threat... Why do we uncheck "Detect Scene Change" ?
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"Crap threat" heheheh. What, like "Put the money in the bag or I'll repaint your living room!"?
Detect Scene Change inspects the material as it encodes it and, if it thinks a frame is dissimilar enough from the previous one, will insert an I-frame at that point. While TMPGEnc usually gets it right, for a long movie there might be many frames it thought were scene changes but in fact weren't.
This leads to more I-frames than is necessary, and since I frames are much bigger than P- or B-frames (10-20kb instead of 2-8kb) this makes for a bigger resulting encode.
The positive side of Detect Scene Change is that it theoretically results in higher quality, but the size trade-off probably isn't worth it.
It also makes prediction harder, since TMPGEnc won't necessarily use a whole GOP to encode each sample but will instead insert new I-frames here and there. This could throw off the prediction by quite a lot.