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View Full Version : 1pass encoding: how to determine the quantizer


bur
3rd November 2011, 09:26
I have a lot of files to convert for mobile viewing. That means I don't need high quality and also exact file size isn't important. To save time I thought of trying 1pass encoding.

But I'm wondering how to choose the CQ factor. In a 2pass encoding quantizers from 1 to 3 were used for I-Frames and the range was even bigger for P-frames. And the resulting quality was as needed. So if I set the quantizer to 2 I'd loose quality in some frame and while wasting bitrate in others.

Is there any way around this or is it a general problem of constant quantizer mode that can only be solved by using constant quality/CRF as is possible in x264?


The thing is so far I'm stuck with using VirtualDub and hence probably Xvid due to this: see other post (http://forum.doom9.org/showthread.php?p=1536040#post1536040)

sneaker_ger
5th November 2011, 19:57
I've left you a reply in the other thread.