AviSynth/VirtualDub Questions

[ivanolo]

I had been using VirtualDub-MPEG2 to rip my DVDs and encode them to XviD using full processing mode until recently, when I read that fast recompress mode is more desirable because it speeds up the process and avoids unnecessary color space conversions. So, I decided to give AviSynth another try, since I had dabbled in it once before, but decided that it was too much of a hassle to use, not realizing its potential.
Now, the first thing I did was create an AVS script to load the M2V file with the DirectShowSource command and the Info command, to see the exact specifications of the stream I was dealing with. AviSynth tells me that the clip is progressive and its color space is YUY2, which confuses me because, from what I understand--and please feel free to correct me if I'm wrong here--MPEG-2 streams should be in YV12, right? Should I use the pixel_type string to specify the color space, then? I'd like to stay in the YV12 color space with no conversions or, at least, the minimal amount of conversions possible. Also, should I use a different method for loading the video, say, by using a plug-in such as MPEG2Dec3? And, one last question, should I stick to VirtualDub-MPEG2, switch to the original version, or get VirtualDubMod?

Thanks in advance.

[manono]

Hi-

The usual method of doing this is to load the vobs into DGIndex, create a D2V Project file, and then open it in VDubMod via the DGDecode.dll (the successor to the MPEG2Dec3.dll) and MPEG2Source, rather than DirectShow source. When you get the DGMPEGDec package, read the Quick Start and DGIndex Manuals included. They will answer all your questions, including the ones about the colorspaces.

[guns1inger]

You can also load the DGDecode.dll as an avisynth plugin, then open your file using mpeg2source()

[ivanolo]

I tried using MPEG2Decoder YV12 2.03a, and it crashes VirtualDub during the 1st pass at around 70%....
I'll give DGMPEGDec a try, then, and I'll post the results. Wish me luck!
Thanks, BTW.

[manono]

OK, Good Luck!

Come back if you need more help.

[ivanolo]

Well, again, thanks A LOT, guys! It worked beautifully.
I have another question now, though. What's the lowest bitrate I can go at 352x240 without getting pixelation? I'd like to burn a couple of long movies to CDs.

[guns1inger]

I don't do much encoding to xvid or Divx, but I would have though at that res somewhere around 500kbps would be reasonable, although not perfect. That would give you around 2 hours.

[ivanolo]

Well, just to let you guys know... I started experimenting and managed to go down to 256kbps without really bad pixelation. A little bit can be seen during a couple of heavy scenes, but it's not as notiable as you'd think, and it's perfect for my purposes.