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weaver4
27th January 2007, 17:53
What does 67% or 75% really mean?

What is the actual equation that is used to go from a quality percentage to a quantizer value?

I thought the value was (100-value)/10 = target quantizer; but I have been told I was wrong.

I also heard the equation ((maxQ-minQ)/100) * (100-quality) + minQ was no longer valid for XviD. The XviD FAQ say that this is outdated but does not say what it is now????
weaver4
28th January 2007, 02:49
Maybe I should of posted this in the AutoGK forum. Your statement actually adds to the confusion, since it is a setting on AutoGK. I had thought it still directly related to the XviD codec setting.

So what does this setting in AutoGK correlate to on the Xvid codec?
foxyshadis
28th January 2007, 04:46
I'll delete my post and move it there then, since they'd probably know much better. Sorry for that, I thought you meant a quality factor in xvid.
BigDid
28th January 2007, 21:41
What does 67% or 75% really mean?

What is the actual equation that is used to go from a quality percentage to a quantizer value?
...
Hi,

Some hints in the Tutorial (step3 target quality):
A Quality encode will give you even quality throughout the movie at your designated percentage. The default is 75%, which will give you very good quality (but for DivX6 default is 60%). Good quality percentages begin at about 67% (Quantizer 3). I don't think there's much point in going above about 80% because then you'll lose some of the benefits of MPEG4's compression abilities.

Did
weaver4
29th January 2007, 00:20
I believe that Len0x said in a previous post that this information was now incorrect.

When I encode in avi.net or staxrip I like to use a quantizer of 3.0 for most movies and 2.5 for my favorites. I am just trying to find out what "Target Quality (in Percentage)" that I should use in AutoGK to get these two quantizers values.
BigDid
29th January 2007, 17:39
I believe that Len0x said in a previous post that this information was now incorrect.

When I encode in avi.net or staxrip I like to use a quantizer of 3.0 for most movies and 2.5 for my favorites. I am just trying to find out what "Target Quality (in Percentage)" that I should use in AutoGK to get these two quantizers values.
Hi,

MAybe for Divx cause I still encode in Xvid with quality from 60 to 65 being average quant (DRF analyser) +- 3.3 to 3.8.
So +-67% nearing quant 3 seems possible.

Did