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rdsii64
May 2, 2010, 05:56 PM
I was experimenting with handbreak today and tried setting the constant quality seting to 100%. what I ended up with was a file that quicktime couldn't play. VLC couldn't play it either. When I tried a second time leaving the constant quality setting at 60%, everything wast just fine. could someone explain why this is.

thanks



tbayrgs
May 2, 2010, 06:09 PM
I was experimenting with handbreak today and tried setting the constant quality seting to 100%. what I ended up with was a file that quicktime couldn't play. VLC couldn't play it either. When I tried a second time leaving the constant quality setting at 60%, everything wast just fine. could someone explain why this is.

thanks

Here (http://trac.handbrake.fr/wiki/ConstantQuality). Go higher than 60% and you'll quickly see your file size increase dramatically with hardly a significant improvement in quality. The fine developers of HB set the :apple:TV preset at that level probably as the best compromise of quality and file size but of course, your idea of best quality may vary.

dynaflash
May 3, 2010, 09:41 AM
The information is also hidden in the FAQ (Frequently Asked Questions). They can be worth a look.

http://trac.handbrake.fr/wiki/SupportFAQ#winsomelosesome

rdsii64
May 3, 2010, 11:10 AM
That is an interesting read, I get the general gist that using 100% constant quality isn't really necessary. However it never really explained why when I tried 100 constant quality, I got a file that quick time could not read.

NightStorm
May 3, 2010, 12:19 PM
That is an interesting read, I get the general gist that using 100% constant quality isn't really necessary. However it never really explained why when I tried 100 constant quality, I got a file that quick time could not read.

Frankly impossible to say without more detailed information, but I'd guess that the size probably exceeded 4GB and the 64-bit MP4 option was not enabled.

dernhelm
May 3, 2010, 12:54 PM
That is an interesting read, I get the general gist that using 100% constant quality isn't really necessary. However it never really explained why when I tried 100 constant quality, I got a file that quick time could not read.

H264 "Constant quality" of 100% amounts to H264 lossless. Quicktime cannot currently deal with H264 lossless. You can however, build a version of mplayer that can.

We were investigating both VC1 lossless and H264 lossless for medical image delivery to the browser. Unfortunately, there are no standard browser plugins that can deal with those formats (you have to roll your own).