Laserdisc capture - a few recomendations please

[Waylander076]

I'm in the UK and I've managed to get hold of a laserdisc player
that plays PAL and NTSC.

I'm going to try and capture some NTSC laserdiscs to convert them
to DVD with my old WinTV PCI card using Virtualdub and the MJPEG codec.

I don't need to convert the capture to PAL as I have a multiregion DVD
player I'm going to keep them NTSC.

The question is this....what frame rate should I capture the Laserdiscs
at 23.976 or 29.97?

Would I need to do an IVCT on the captured footage?

Thanks
Waylander

[junkmalle]

You have to capture at 29.97 fps because that's what's comes out of the player. For DVD I would IVTC them down to 23.976 if possible (film source).

[Waylander076]

Thanks for that....that's what i thought but wasn't sure!

[lordsmurf]

I wouldn't. Just capture the source 29.97 and leave it alone.

[dphirschler]

If you can't get a perfect IVTC, then do as lordsmurf says, leave it alone. But if you can get the IVTC perfect, then I see no reason not to do it.


Darryl

[Waylander076]

Okay...why leave it at 29.97 and not do an IVCT down to 23.976?

Would leaving it at 29.97 give a better result in someway or is the IVCT
down to 23.976 not required when the source is captured at 29.97?

EDIT: What is a perfect IVCT????

[lordsmurf]

Perfect IVTC is highly unlikely.

[junkmalle]

I IVTC stuff recorded from TV and VHS all the time. When I'm lucky, say 1 out of 10 movies, a whole movie can be IVTC'd in one pass of VirtualDub. Most of the time (8 out of 10) I have to split the movie into 2 to 10 sections to be joined later. The last 1 out of 10 movies has the telecine pattern so badly mangled that I just leave it interlaced.

The movies that are badly mangled tend to be made-for-TV movies. I suspect most of them were shot on film, roughly edited, telecined, then edited again as interlaced video. The telecine breaks are almost always at scene transitions.

For example a few days ago I recorded <edit>Hitchcocks's Rear Window</edit> off Turner Classic Movies. There was a single telecine pattern break in the entire film.

If you're going to watch the video only on a standard interlaced TV it doesn't matter if you IVTC or not. If you do IVTC the DVD player is simply going to telecine the video again for display. I prefer to IVTC because it makes the the movie much more watchable on a computer. And I'm usually not creating movie DVDs, but rather XVID AVI files.

[junkmalle]

What is a perfect IVCT????

A perfect IVTC is when you perfectly restore every original film frame from the interlaced video. In my experience, the automatic IVTC features of VirtualDub and TMPGEnc don't do this very well. You will get many duplicate frames, dropped frames, and some interlaced frames sneaking through (the result will be jerky). You have to use the manual IVTC pattern settings.

I've gotten pretty good at this in VirtualDub, it only takes me a few seconds to determine the proper offset value when using "reconstruct from fields - manual" mode.

[tedkunich]

What is a perfect IVCT????

A perfect IVTC is when you perfectly restore every original film frame from the interlaced video. In my experience, the automatic IVTC features of VirtualDub and TMPGEnc don't do this very well. You will get many duplicate frames, dropped frames, and some interlaced frames sneaking through (the result will be jerky). You have to use the manual IVTC pattern settings.

I've gotten pretty good at this in VirtualDub, it only takes me a few seconds to determine the proper offset value when using "reconstruct from fields - manual" mode.

On a clean source, such as an LD, there is no reason that proper IVTC cannot be done automatically. Using the Decomb package for Avisynth, I have had exellent results. Even if the movie does switch its cadence (which they do from time to time) the decomb plugin never missed a beat on any of my conversions.

T

[dphirschler]

Perfect IVTC is achievable with LD source. If it proves too difficult, then leave it alone. But I will always attempt it, and so far I have not been beaten.


Darryl

[Waylander076]

Thanks for the replies so far guys!

the general thought then is as it's a clean source (LD) capture at 29.97
and then try an IVCT.

If the IVCT works ok then all well and good, if not then don't worry
about it too much just leave the source at 29.97.

If i go the Decomb and Avisynth route (which I probably will)
what settings for decomb do you recommend?

Thanks agin for all the input!

[tedkunich]

Thanks for the replies so far guys!
If i go the Decomb and Avisynth route (which I probably will)
what settings for decomb do you recommend?

For NTSC LD captures, I use this:

Telecide(order=1, guide=1,post=0,nt=30).Decimate(cycle=5,quality=3)



T

[Waylander076]

Will give it a try ...thank you