fixed quant encode vs. 2-pass at same filesize

[Raptus]

Hi,

i was doing some encodings of the same source with both fixed quant modes and 2-pass, which gave me very near filesizes and similar average quants for the 2-pass encode. So i was wondering if its safe to say that the 2-pass encode should have subjective better quality, considering that the encoder can do "more inteligent" quant distribution decisions.

I am in doubt if that is true in this particular situation because i used q=2 in the fixed quant one, which means that in the 2-pass both lower and higher quants were used to achieve the same average and I don't see much benefit in using q=1. Or am I wrong? Can a mixed quant (with q's=1) encode surpass the quality of a fixed quant=2?

I would investigate myself if i hadn't deleted one of the files (the question only came later to me).

thanx in advance.

[Soulhunter]

IIRC, @ defaults the lowest quant is limited to 2 !!!

So, a 2Pass encode that has the same filesize as a Q2 encode, should have identical quality then... :rolleyes:


Bye

[Raptus]

Nope, q=1 got used too, shown in the xvid stats window.

[Soulhunter]

Really... :confused:

After hitting the "load defaults" button, XviD v.1 sows me this !!!

http://img16.imageshack.us/img16/3807/snap000075.png


Bye

[sysKin]

Single-pass fixed quant gives better results than two-pass. Don't count on ratecontrol being inteligent, it's not - you can make it more inteligent by extra curve compression settings, but if you don't, it's just as stupid as computers are.

Soulhunter :confused: what kind of xvid do you have...?


Radek

[Soulhunter]

Originally posted by sysKin
Soulhunter :confused: what kind of xvid do you have...? Hmm, this question gives me the suspicion that the default isn't 2... :scared:

Anyhow I can only tell what the GUI tells me !!!

And for the version... ;)

http://img12.imageshack.us/img12/2470/snap000076.png


Bye

[sysKin]

Originally posted by Soulhunter
And for the version... ;)

http://img12.imageshack.us/img12/2470/snap000076.png
1.1.-126 "Selam" aka "beta2". That is really really old now ;))

Radek

[Bogalvator]

You're using the Selam build, that was RC2!

The lowest quant defaults in the versions since then have been 1.

Edit: Tsk, too slow as usual.....

[P0l1m0rph1c]

Originally posted by Soulhunter
Hmm, this question gives me the suspicion that the default isn't 2... :scared:

Anyhow I can only tell what the GUI tells me !!!

And for the version... ;)

http://img12.imageshack.us/img12/2470/snap000076.png


Bye

OMG! Where have you been all this time? ^^

[Soulhunter]

Yeah, this confuses me too... :confused:

Something seems to be very wrong with my box !!!


Here I download the latest XviD build...
http://img18.imageshack.us/img18/332/snap000078.png

Here is the downloaded file I install then...
http://img18.imageshack.us/img18/453/snap000077.png

But the GUI still shows me this...
http://img18.imageshack.us/img18/4053/snap000079.png

Even after re-boot, un-install, re-install its the same... :(

Bye

[Leak]

Originally posted by Soulhunter
[B]Yeah, this confuses me too... :confused:

Something seems to be very wrong with my box !!!

How about doing a search for "xvidvfw.dll" on your harddisc? Looks like you've got some old DLLs lying around in the wrong places, i.e. outside your XviD install path but somewhere VFW looks for codecs...

np: Richard Devine - Halicrafter (Asect : Dsect)

[Soulhunter]

Hmm, the registry entry shows its v.1 !!!

http://img11.imageshack.us/img11/4535/snap000081.png

No problem I think I its time to install WinXP on my 2nd HD...

If I see a fresh XviD v.1 then, I simply swap all my other files to it (except the windows stuff..) !!!

So, I see ya back in estimated 4 hours... ;)


Bye

[Soulhunter]

So, its done n' also faster than estimated !!!

Now I have a nice v.1 GUI too... :)

http://img11.imageshack.us/img11/5849/snap000082.png


Bye

[minolta]

@Soulhunter, I had the same XviD problem as well for the longest time. I think we both used the same faulty installer, and I suppose many others have same problem as well (check now!!!). My only way to uninstall XviD was to finnally delete every reference I found in the registry (it's in about 6 places). Only then did the Koepi's installer work. From now on I uninstall instead of trusting it'll upgrade.

Others, if you've installed XviD multiple times, you should definitely check your version...

[Soulhunter]

Someone knows what causes this obscurity ???

Was it really the Selam build Ive used, or v.1 with a Selam info GUI... :confused:

No matter, everything works well now !!!

Time to start the next encode... :D


Bye