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Old 8th April 2007, 19:58   #2  |  Link
akupenguin
x264 developer
 
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Join Date: Sep 2004
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[QUOTE=check;986387]Hi all, I was wondering if someone could take the time to explain why x264 temporally blurs the quantizer curve[QUOTE]
It makes quality more stable. Especially in anime, where the framerate of the content is often less than the nominal framerate of the video, so in two consecutive frames one has motion and the next doesn't. Without any temporal blur they'd have very different qp, but the optimal encode is to make them the same.

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why blurring is applied twice
The ratecontrol I stole from libavcodec already did one, and I added another algorithm I liked better.

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and what units (or scale) the two settings are in.
frames.

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On a somewhat related note, as I understand it, the default --qcomp setting moves the bitrate distribution from what the encoder feels is optimal to a more constant distribution. How does it do this, and why is this not set to 1.?
It's hard to define optimal. But no, the default qcomp is my attempt at optimal, not a compromise between optimal and something else.
qcomp=1 would be identical to cqp.
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