Help: zone @Q2 vs @W1.0

[Plamen234]

Can anyone tell me what is the difference between a zone (a whole clip) encoded at Q2 and a zone @Weight=1.0 in the 1st pass?

I did some 2 encodings on a 25min clip and a ssim comparative test (with the 2nd-pass avi).The ssim results showed that no difference could be seen during playback (in my opinion).
I found that the 1st-pass comsumed time is about 2h for Q2 and some 20min for W1.0 - which pizzles me. And the two .pass files are also different, StatsReader gives 294MB for Q2 and 265MB for W1.0.

Any info is appreciated.

p.s. windows, XviD-1.1.0-30122005.exe (628kb) koepi's, athlonXP 1600+

[Koepi]

If you do a first pass at weight 1.0, it's being done with fixed quantizer 2 and some speedups. If you set a fixed quant zone in the first pass, these speed optimizations aren't active.

Cheers
Koepi

[Plamen234]

I see.
Thank you.

[Elic]

Plamen234 >> StatsReader gives 294MB for Q2 and 265MB for W1.0
Koepi > first pass at weight 1.0, [...] some speedups. [...] fixed quant zone in the first pass, these speed optimizations aren't active.
Does this mean that "turbo" and/or "full quality 1st pass" are affected by Q2 (and results in so much difference in size)? But what if I don't use "turbo" and always use "full quality" - are W1.0 and Q2 identical in that case?
And/or, does this mean that Q2.0 is more precise?

[squid_80]

Does this mean that "turbo" and/or "full quality 1st pass" are affected by Q2 (and results in so much difference in size)? But what if I don't use "turbo" and always use "full quality" - are W1.0 and Q2 identical in that case?
And/or, does this mean that Q2.0 is more precise?
q2 = full quality first pass w1.0.
q2 with turbo = full quality w1.0 with turbo.
w1.0 without full quality, turbo makes virtually no difference. (XVID_ME_FASTREFINE8? ask sysKin.)

[Elic]

squid_80
> q2 = full quality first pass w1.0
:thanks:

[Plamen234]

Actually, Koepi said sth different and didn't mention "turbo" at all.

[sysKin]

Actually, Koepi said sth different and didn't mention "turbo" at all.
No, he said the same thing, he didn't mention Turbo like he didn't mention b-frames - they're irrelevant.