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View Full Version : Sizing Pass vs. Re-One-Pass


DoctorM
23rd February 2011, 06:36
A question I've been meaning to ask a long time and I can find no info on anywhere.

When using CCE for a one-pass vbr encoding, if the final file is oversized or undersized, is there a quality hit or improvement if you do a 'sizing pass' (single pass with multipass using the OPV's .VAF)?

In cases where I'm unclear how much to adjust the Q value by and/or with a slow set of filters in avisynth, a sizing pass would be a great tool.

Part of me thinks it'd be like doing one more pass to a multipass encoding, but something tells me that sizing would use a different bit rate making the vaf unsuitable and hurting image quality.

Fishman0919
26th February 2011, 04:12
This is a test I did some times back LINK (http://forum.doom9.org/showthread.php?p=973580#post973580)

You can see that 3 pass no AQM and 1 pass VBR (OPV) did the best... I've done this test with several different clips... all giving pretty much the same results.

From the times I've done additional passes after the 1 pass VBR, even a third pass, it drops quality.