How to compare Xvid rips with different settings ?

[nightrhyme]

I'm in the process of making multible encodes of a movie to compare effects of the different Xvid settings. Quantization type,AQ,Qpel,GMC,VHQ Mode, Trellis Quantization and Chroma Motion.

What I would like to know is how to compare ?
What am i looking for ?
Which frames should I use ? Ones with a lot of motion or ?
Should i compare screenshots or watch the clips ?

What I do is capture the same frame with VdubMod and compare with source.
But how do I get a screenshot of the correct source(DVD)frame. I just use one of the Avisynch scripts Gknot geneated and opened it in VdubMod. Is that the source ?

A lot of questions :rolleyes: Hope you guys can answer

Attached a few screens for your pleasure:
These all done with Gknot 2-pass
Source PAL-DVD
Bitrate: 1564 kb/s
Original avi resolution: 696 x 384

Source. Just noticed the black bars. Damn don't know why this is. Used the Smart Crop feature in Gknot. Any advice on that ?
http://img16.exs.cx/img16/2127/source.png

Quantization type:MPEG ,AQ, Qpel, GMC, VHQ Mode 4, Trellis Quantization and Chroma Motion
http://img16.exs.cx/img16/3061/hele-pisset.png

Quantization type:MPEG ,AQ, Qpel, GMC, VHQ Mode 4,and Chroma Motion ----- basically without Trellis
http://img16.exs.cx/img16/4789/No-Trellis.png

Quantization type:MPEG , VHQ Mode 4, and Chroma Motion ----- basically without Trellis and Qpel
http://img16.exs.cx/img16/9866/No-trellis-no-qpel.png


//Thanx in advance and excuse my Newbeeness:rolleyes:

[gircobain]

You should save screenshots as lossless png's

By upscaling and compressing them to jpg you introduced even more lossy compression which makes them useless for any kind of comparison

[nightrhyme]

Originally posted by gircobain
You should save screenshots as lossless png's

By upscaling and compressing them to jpg you introduced even more lossy compression which makes them useless for any kind of comparison

Done.
Any answers to my questions ?

[Koepi]

Yes, a very unpleasant one:

head over to www.doom9.org and read the guides - one for encoding without gknot (some things fail if you try to automise them, look at your cropping which left black bars), one for encoding with xvid 1.0, maybe one about avisynth.

And then make sure to read i.e. crusty's FAQ. It'll help you understand the settings of xvid. If you understand them, you can already guess what you're looking for.

You can't get any better answer because the personal taste and preferences vary from person to person. I could describe you what _I_ would watch out for, but it can be totally to your disliking.

So you have to do all the tests yourself to find your preferences, sorry for that. The other side is, after that, you'll encode top quality for your eyes.

As this thread will lead to nowhere else than some people flaming each other over their preferences, I'll close it now, before any harm is done.

Regards
Koepi