Star Trek is progressive AND interlace - can it be encoded?

[mojo]

I'm backing up some DVDs of "Star Trek: The Next Generation" and have been having a hard time encoding them as SVCDs.

DVD2AVI shows the source as being alternately progressive AND interlaced (and subsequently both film and NTSC). I think the live action shots are film and the FX shots are interlaced.

Anyway, this means that when I encode at 23.97 with 3:2 pulldown, the live action looks great, but the FX shots stutter and look jerky.

What can I do make the whole disc happy?

Thanks.

[wulf109]

I do them by remuxing the vob file to mpg and encode directly in Tmpeg with excellent results. I use the standard SVCD template with 720x480 resolution.

[sterno]

You may want to look in to the decomb filter for avisynth, it can handle hybrid material in an intelligent manner. No matter how you do it you won't be able to use Force FILM or encode at 24fps, the CGI was rendered directly to 30fps so reducing it to 24 will give you the jerky playback you're seeing.

[mojo]

Thanks for the replies - but I'm still not clear...

Firstly, how do I remux the .VOB into MPG? I know how to use TMPGenc, but are you saying I should turn the AVI into an MPG before I encode it? How does that solve the 30/24 fps issue?

As far as AVISYNTH goes, I'll take a look. Although if I don't force film and encode at 24 because the fx are at 30, won't all the live action start stuttering?

My first attempt to encode an episode at 24 gave me excellent results for everything except the FX shots - they were quite jerky and looked exactly like you'd expect if you tried encoding 30 at 24.

If anyone has made an SVCD out of these episodes and is sure they got smooth playback from the whole thing, let me know how you did it!

[easydvd]

I did a dvd->svcd with these. I used AVISynth to frameserve into CCE with "GreddyHMA.dll" for de-interlacing. It's based on the greedy de-interlacer from dScaler and personally I think it's the best adaptive de-interlacing that I've seen.......I can do live TV that's a mix of video and film and still get good results with it.

Let dvd2avi do it's thing without "force film"

Use a script similar to this one with avisynth to frameserve it

AviSource("D:\tv.capture.for.edit\CAPTURE.AVI")
LoadPlugin("C:\plugins\Tweak.dll")
LoadPlugin("C:\plugins\GreedyHMA.dll")
Crop(12,4,-4,-4)
BilinearResize(320,240)
Tweak(bright=2,cont=1.25)
GreedyHMA(1,0,4,0,0,0,0,0)




Obviously this is for something I'm doing but you can adapt the settings for GreedyHMA into your script and use it. You can find more info and documentation for this at www.doom9.org

[poopyhead]

or you can just turn off forced film in dvd2avi and in tmpgenc, make your output as 29.97 fps + interlaced (no 3:2 pulldown)

this will still look really nice on your TV (however, there will be loss in quality compared to encoding at 23.976 fps + 3:2 pulldown because there are more frames to split the bitrate between)... however, your dvd rip will be interlaced, so your progressive monitor will not play it very well...but TV is interlaced, so there shouldn't be a problem.

[mojo]

I'll give it a try. But if I rip and encode the whole show at 29.97, won't the 24fps segments look choppy?

[sterno]

I'll give it a try. But if I rip and encode the whole show at 29.97, won't the 24fps segments look choppy?

No, dvd2avi will do the same thing that your DVD player does before sending the video to your TV. The benefit of running the material through a filter is that you can convert it to a progressive stream (for computer playback or VCD), but it will also work fine as an interlaced SVCD with no filtering.

[mojo]

Ok, I found the solution to my problem in another forum - here's the key to anyone who needs to do the same thing with a Star Trek (or any other disc) that contains both film and NTSC elements!

- Rip it normally
- In DVD2AVI, do NOT force film - leave field option as default
- In TMPGenc, encode as an interlace SVCD at 29.97
- Make sure TOP FIELD FIRST is selected
- the Encode mode should be INVERSE 3:2 PULLDOWN

Of course, this is specifically targeted at playing back on TVs, not on computer monitors (although both seemed to give good playback).

If anyone cares to explain exactly why this works and how inverse 3:2 pulldown somehow allows 24 and 30 fps footage to coexist peacefully, I'd love to hear it!