compressibility check, change settings

[TheWiep]

Hi,

I recently started ripping and I followed the XviD guide on the doom9 main site.
Everything went well but when I did the compressibility check, the percentage went to 32.9% for Monsters Inc. and dropped to 19.5% for Oliver & Co.
The guide says that above 40% is good quality but since none of these 2 get there...
I was hoping someone could tell me what setting or so I have to change in order to get a higher percentage.
I didn't know if I should post it in newbies or GKnot so I ended up putting it here :)

Thanks so much in advance.

[jggimi]

Two immediate options come to mind right away: Lower resolution

Larger file sizeThere are other ways to improve compressibility, such as using B-frames, using temporal smoothers ... but these two are the easiest way to increase b/p*f.

[TheWiep]

Thanks for the fast reply,
As the movies only are about 1hour 30min one should be able to rip them to good quality 1 cd
as I recall correctly I used Smart Crop All because the guide told me so (this makes me very newbie I guess :) )
If I was to change the resolution, how should this best be done?
Am I still able to use Smart Crop All?
Will the picture be worse, same or better when seeïng it in full screen?

Thanks.

[manono]

Hi-

As the movies only are about 1hour 30min one should be able to rip them to good quality 1 cd

Not necessarily. I've plenty of 90 minute movies that required 2 CDs at that default resolution. I know that Monsters Inc. isn't very compressible. Don't know the other movie.

If I was to change the resolution, how should this best be done?

In the middle of the Resolution Tab are 2 buttons just below Width x Height. Start hitting the down button. Or move the slider that's a bit further down. Then run another compression test. And as jggimi suggested, judicious use of filters and B-frames will help with the compressibility.

Am I still able to use Smart Crop All?

Yes, but I don't trust it. I'd recommend cutting away the black bars with Pixel Crop, keeping an eye on Aspect Error at the same time.

Will the picture be worse, same or better when seeïng it in full screen?

Both better and worse in some ways. You'll lose some detail by lowering the resolution, but you'll gain in overall quality by having fewer compression artifacts (especially noise) that result from having high average quants.

The guide says that above 40% is good quality...

The guide (http://www.doom9.org/gknot-xvid.htm) sort of says that:
60% or higher will pretty much guarantee that you'll get pretty good looking results. Going over 80% is a serious overkill and you should rather increase the resolution. Values in the range of 50-60% still look pretty good and 40-50 is still OK, especially when you activate B-frames.
But for high quality DVDs of newer movies, I'd want to be much closer to 60% than to 40%.

[TheWiep]

aha, this has been very interesting for me :)
I hear a lot of people say that when a rip has ... resolution and ... bitrate it is good quality, but if I understand correctly this is not always true.
If a movie is good compressible quality will be good and if it isn't like Monsters Inc. the quality won't be that good.
Did I understand this correct?

I will start playing around with the resolution and check out that pixel crop this week.
Also, where can I find more info on them b-frames?

Thanks so much already for the replies, this has been a great help for me.

[manono]

Hi-

If a movie is good compressible quality will be good and if it isn't like Monsters Inc. the quality won't be that good.
Did I understand this correct?

It depends on the bitrate and the resolution. If you only want to make your movies for 1 CD, then there are many movies at that default resolution that won't look good. Try an experiment. Run the first pass. Then run one second pass for 1 CD, and another second pass for 2 CDs. Then compare. An animated movie like Monsters Inc. will show the differences very clearly. If you give it enough bitrate, any movie can be made to look good. Almost as good as the original DVD, anyway.

Here's some information about B-Frames:

http://forum.doom9.org/showthread.php?s=&threadid=19436

[jeremymacmull]

surely thats a bit complex for a relative newbie!!! :D

basically follow the guide which says for one cd rips the bits per pixel should be above .17 ( i think) and for two cds try to keep between .25 and .27 (if i remember correctly) the main thing to look for is the compressibility as it says if it is above 60% after doing a compressibility check at the resolution u want then keep that if it is below consider moving to another cd ie two cds or lowering the resolution

AS For monsters inc i have a perfectly good one cd rip of it so it is possible !! hope this helps

JEREMY

basically read the guide again and it should become apparent.

[manono]

Hi Jeremy-

surely thats a bit complex for a relative newbie!!!

Probably, but that's all I could find with a quick check. I know there's more around. TheWiep can dig them up himself.

AS For monsters inc i have a perfectly good one cd rip of it so it is possible

Did you use 640*xxx? Any tips you can pass to TheWiep? Filters and the like? I only made an SVCD of it, so I can't say, but I do remember reading discussions about it where someone said it was difficult to compress. Here, I just tracked down the thread:

http://forum.doom9.org/showthread.php?s=&threadid=34960&highlight=Monsters

[jeremymacmull]

Firstly if you only recently started ripping i reccomend the divx 5 route and NOT the xvid route as its a much harder thing to get perfect compared ie divx 5.05 is newbie friendly (and a lot quicker)

Also could u post the settings u used for the XVID rip maybe there is your error. VHQ 1 etc or how many b frames u used etc. If in doubt about what these mean then i strongly reccomend usind divx 5.05 instead as xvid is not really the most newbie friendly codec.

Um i cant remember fully im pretty sure i did NOT use 640X YYY but the one below that i think its 608X yyy (not sure of the exact res)

I remember I used soft bicubic and b frames and light phyco acoustics (DIVX 5.05)

and as far as i know the rip was very nice perfectly acceptable (im using the PAL UK version)

JEREMY

AT the end of the day tho if you read that thread mentioned it all depends on WHAT quality u want to go for. im perfectly happy most of the time with 1 CD rips others are not it depends how A**L one is about quality.

quality is a subjective thing

my advice is do the 1 cd rip using the settings i mentioned and if not happy go down the 2 cd route. Cos face it its only another 20-40 p for another cd which is not really a big deal