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Old 18th October 2018, 16:45   #6448  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by Boulder View Post
I'll post my results as soon as I finish the 720p tests. From what I can tell is that 1080p requires slightly different parameters, but of course it could be that things have changed so much under the hood that my set of parameters have been obsolete all the time
Pretty much any settings from before x264 2.4 are invalid now due to the new lambda tables. Lots of other things have improved, but that was probably the biggest change.

Quote:
What I already found strange is that deblock doesn't really affect bitrate. For example deblock 6:6 ended up around the same size as deblock 0:0.
Lots of codecs’ internal decisions are done ignoring in-loop deblocking to improve speed. So that’s not terribly surprising. And if this is CRF, it is a delta from QP based on spatial complexity, so it’s not surprising that it would change.

It IS surprising that you wouldn’t see bitrate OR QP change, even with a significant loss of detail. Not that using 6:6 is something anyone is likely to do in practice. But reduced detail should result in lower bitrate and/or QP. With lowered detail (including grain/gain noise), prediction should be more efficient...

Maybe log your repro for this as an issue for MCW?
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