constant quality preset

General questions or discussion about HandBrake, Video and/or audio transcoding, trends etc.
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rcrh
Posts: 41
Joined: Wed Feb 11, 2009 1:49 am

constant quality preset

Post by rcrh »

OK, I've read through a bunch of the discussions concerning bitrate, two pass options, and the CQR settings. I thought I had understood the key point being that CQR profile does a better job with similar bit rates then doing two pass encodes. Previous to this I had been doing two pass encodes using target bitrates of 2500 since this seems to be what most of the players out there use for their own files (AppleTV, PS3, Xbox). Then, when I had a bluray source I increased it to 4000.

After reading the discussions about CQR I decided to reencode some files and have had VERY mixed results. Using the recommendations here I used 55% CQR for a bluray source (and reduced the widthxheight to 1280x720) and got great reduces. The file looked every bit as good as my 4000kbs encode and the resulting file was smaller. YEAH!

But, I'm getting a completely different result from a standard DVD source. Using the CQR Highprofile with 61% I'm getting bigger files at higher bit rates. This seems to be the exact opposite of what I was expected.

I'm assuming I'm doing something wrong. Any thoughts?
jbrjake
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Joined: Wed Dec 13, 2006 1:38 am

Re: constant quality preset

Post by jbrjake »

rcrh
Posts: 41
Joined: Wed Feb 11, 2009 1:49 am

Re: constant quality preset

Post by rcrh »

Lots of tech details, but nothing very conclusive.

Anyone else have some comments?
TedJ
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Joined: Wed Feb 20, 2008 11:25 pm

Re: constant quality preset

Post by TedJ »

I think jbrjake was suggesting you use the updated preset linked in that thread. If you're set on using the Constant Quality preset in 0.9.3, you'll probably want to tweak the psy-trellis setting as it was set a little too strong, which caused quite a bit of bloat.

On the advanced pane, change "psy-rd=1,1" to "psy-rd=1,0.2" and you may want to drop the CQ percentage to 59%.
simkna
Posts: 4
Joined: Thu Feb 05, 2009 5:06 pm

Re: constant quality preset

Post by simkna »

I have tried creating a preset in the gui version using the cli settings, but have failed dismally. Can somebody give me an advanced string I can enter to allow me to create my own "0.9.4 High Profile" setting?

Thanks

Simon.
rcrh
Posts: 41
Joined: Wed Feb 11, 2009 1:49 am

Re: constant quality preset

Post by rcrh »

Ted J,

thanks for that gentle slap to the head. I guess my eyes started to swim as I was reading the post the first time. But, even know I'm unclear as to which present is being recommended for CQF encodes. Is it the new AppleTV preset?

I'll give it a try and I'll try the manual adjustments to the High Profiel CQF.

Thanks.
rcrh
Posts: 41
Joined: Wed Feb 11, 2009 1:49 am

Re: constant quality preset

Post by rcrh »

any other thoughts on this?
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