another oversizing thread

[illdrift]

Sorry to bring up another oversizing thread, but i still haven't solved my problem after trying many different methods ive heard mentioned in other posts, such as changing the minimum quantitizers from 1 to 2 if i read correctly. It only oversizes occasionally with certain video streams. I've got xvid 1.0.1 final if it makes a difference. I've tried playing around with different things like changing the VHQ mode from 1 etc (btw im not very literate with all this stuff so bare with me please). The only thing that seem to have made it the right size (100mb) is changing the overflow control strength and overflow degration to 8-10. The size is right then but the video is blocky/noisy around edges etc. Usually its 140mb, or with the quantitizers at minimum of 2 it turns out at 40mb.

So any ideas to fix my problem? Cheers

[Manao]

We need more information ( first pass size, for example, you can get it if you open your first pass stats file with Stat Reader ( bundled with XviD ), duration of the clip, resolution, source type ( mpeg, mpeg2 ) and content ( anime, movie ) )

With the information you gave, what is likely to happen is the following :
Your video is very compressible, and the first pass size is around 40 MB ( which means that at constant quantizer 2, the video would take 40 MB, and that limiting the quantizer to 2+ wouldn't allow you to reach the 100 MB you're wanting ). The bad quality you're getting with changing the overflow settings is likely to be in fact already present in the source you're encoding.

To solve your issue, I advise you first to get the latest beta ( 1.1 ), which solve some issues concerning the rate control algorithm ( and especially oversizing at default settings ). Other workarounds (especially for the quality problem ) might come if you give more information on your video.

[illdrift]

k thanks for heading me in the right direction. Installed xvid beta 1.1, the source is the staind music dvd, specifically the video epiphany. If you havent seen it before, its a rainy and dark throughout the whole song. im using vfapi to read from the .vob files.

It is 4 mins 29 secs long.
The audio is extracted and encoded to ogg at 192kbps and ends up as ~5mb.
I use the following filters on the video, oh aqnd its vdub 1.5.2:
nulltransform (with cropping)
resize (to 800x450, precise bicubic A=1.00) - its that res so it plays on my tv without having to stretch the picture.
smart deinterlace 2.7beta2 with blend instead of interpolate in motion ares selcted, and use cubic for interpolation selected. All the rest is default.

Then i do the 1stpass with xvid, save it to run later, and then the 2nd pass set to 95000kb (~95mb) and save to run later again. The idea is for it to end up ~100mb. Then i run the jobs panel.

The stats reader says 39mb for that video.pass file.
I had a similar problem with the anime Noir, and some other video streams i cannot remember. The 140mb 2nd pass with default settings doesnt have the blocky/noise areas compared to the 100mb 2nd pass when i changed settings. So its not the video source.

With the newer xvid i still get the same 140mb video

Thanks so far

[illdrift]

so anyone have any ideas how to solve my problem?

[Manao]

Sorry, i didn't see your first answer.

OK, so first, the oversizing issue. The best explanation i can give you there is Koepi's : search for his post on this thread :

http://forum.doom9.org/showthread.php?s=&threadid=89260&highlight=oversiz%2A+xvid+overflow

On a sidenote, i don't know why you want the filesize to be 100 MB, but seeing that the first pass size is 39 MB, i think you should aim at a lower bitrate.

Then, the quality issue. Firstly, an obvius error : you deinterlaced after resizing, that is bad and should never be done : deinterlacing must occur before resizing.

Secondly, you're filtering with virtualdub. Though it's a perfectly valid and easy way to filter a video, avisynth would allow you to do a far better job. It won't be as easy, of course, but results will likely be far better. I advise you strongly to search avisynth forum for scripts such as IIP and LimitedSharpen. Though slightly complicated for a non avisynth user, i hope that those thread are enough decoumented to allow you to use these filters without much trouble.

The effect of these change in the filtering part of your encoding will likely be a higher first pass size, and of course a higher quality.

[illdrift]

alrite thanks for that, i mite try using avisynth and a more appropriate video size. Doubt ill have any problems with this method instead, so thanks for the help :)