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Old 18th November 2008, 01:05   #2  |  Link
Dark Shikari
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Join Date: Sep 2005
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Pre-scenecut tends to be more aggressive than scenecut, especially in the case of psy-RD, as psy-RD tends to bias against intra-blocks but is only taken into account in non-pre-scenecut.

It chose scenecuts there because those frames were basically completely uncorrelated: they were completely smoke-filled, leading to be basically nothing but grain, so this resulted in the entire sequence being encoded as I-frames.

Generally, I think pre-scenecut tends to be more accurate. It might be an interesting project, sometime, however, to make pre-scenecut more adaptive to the effects and properties of psy-RD.

Edit: Just tested, and even with psy-RD, there's no point in making them P-frames. The frames are over 80% i8x8 blocks at CRF18. It does get a bit less optimal at higher CRFs though.

Last edited by Dark Shikari; 18th November 2008 at 01:13.
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