Decomb for MST3K

[LevelB]

I would appreciate any pointers I can get for this.

I am trying to encode some old VHS tapes of MST3K. It was suggested to me on another site that I should use decomb/avisynth for this type material. The clip has some sections that are video, most of the clip is NTSC 3:2 pulldown material overlain with video.

After reading the decomb helpfile I ran the clip through decomb/avisynth using the default parameters for processing hybrid clips:

LoadPlugin("decomb.dll")
AVISource("hybrid.avi") <- this points to my clip
Telecide()
Decimate(mode=1)

After 4 hours of processing in VirtualDub, the output clip does not look any different than the input clip. What should I be looking for? Also, are my settings even close to what they should be?

I have been encoding these tapes using VirtualDub|NanDub for some time, but am competely new to decomb/avisynth.

Thanks for any|all help.

[Suzahara]

How were you expecting them to look different? Decimate() only changes your framerate from 29.97 to 23.976 (on the defaults. NTSC material is implied). Is interlacing left? Is there any choppy motion? If not, then you did it right. And sometimes for choppy motion, nothing can be done, there's always tradeoffs.

[LevelB]

Just to be sure we are talking about the same thing - decimate() changes the framerate, but decimate(mode=1) does not, correct?

Can you (or anyone) suggest some basic settings for me to experiment with on this type material?

Thanks

[Suzahara]

Originally posted by LevelB
Just to be sure we are talking about the same thing - decimate() changes the framerate, but decimate(mode=1) does not, correct?

Can you (or anyone) suggest some basic settings for me to experiment with on this type material?

Thanks

From the decomb documentation:
If mode=1, instead of discarding the most similar frame, Decimate() will either replace it with a frame interpolated between the current frame (usually a duplicate of the preceding frame) and the following frame, or it will pass the frame through as is. The choice between these two depends on the threshold parameter setting and on how different the frame is from its preceding frame (see below). Decimate(mode=1) is useful for hybrid clips where you do not want to reduce the frame rate but want to ameliorate the effect of duplicate frames that are emitted by Telecide() (frames that are normally removed with mode=0).


I'm not sure what your source is like though. If you could post a small clip of the original source, perhaps I or someone else can test settings.

[LevelB]

First, thanks for the help I have received in the forum and via email.

I guess I should explain what I have. I captured 2 hours of MST3K video from an old source tape using the huffyuv codec|VirtualDub. Edited out the commercials, demuxed the audio, then saved it back as an avi with huffyuv again, leaving me with a 36gb file that is as I described in my first post. I then ran it through avisynth|decomb using VirtualDub, with the settings as described in the first post, saving it again as an huffyuv avi file. This file is ~300mb smaller than before using avisynth|decomb, and very nicely deinterlaced, but I wonder if someone can suggest other settings that might get me even better results.

I will go ahead and clean it up, generate a 700mb file for the project I am working on and author a DVD for myself :) see what it looks like. Thanks again, I do appreciate this site.