Compressibility check settings different from q=2. Is it possible?

[yotsuya-san]

Hi all! I've searched the forum but it seems that my question hasn't answered yet.
I would like to do a compressibility test though GK using a quantizer different from 2. So I could use the resolution slider to find the right resolution to encode my avi let's say at q=2.8 (and fit it, for example, in 1 cd).
No matter what value I choose in compressibility section (codec settings) in "Save .avs" window, GK uses always q=2. Is this by design? I have check this though GK and Enc, and they gave me very different results (GK: 68,9%, Enc: 96,76%). In fact, when you change codec settings in GK (comp test) and press Ok, then press "codec settings" again, the value of q is again 2.

Please help me!

Bye, Yotsuya.

[manono]

Hi-

I'm near the limits of what I know about this, so if anyone else can help out, then feel free to do so. Yes, the GKnot compress test is always done at Quant 2, and using jonny's Enc. you can pick your Ave. Quant. But the results are comparable. That is, if you set 2.8 in Enc and aim for around 100%, that will be similar to doing the test in GKnot and aiming for 70% or so. If I'm not mistaken, jonny's method (without being able to choose the Ave. Quant) is incorporated into GKnot's compress test. Another way to look at it is:

2.0/2.8=.714=71.4%

[yotsuya-san]

Hi Manono!
jonny told me the same formula. Though I was a little mathematically sceptical about it at first, after some tests I am convinced now, so I won't bother you all again.
Thanks, and bye.

[jonny]

Hi Manono! :)

@yotsuya-san:
Hi!
Yep it works, i've done testing some time ago about this, there is a little deviation from the formula (the curve change a bit depending on the codec-settings-clip used)... anyway can serve well your purpouse.
I'm not a codec developer, so i can't go more deeply :(
(two italians that talk in english... funny ... :D )