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Laserdisc capturing - what is to be considered?

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 (Edited)

Hey there!

Inspired by a lot of the restoration attempts for the OT here I've recently aquired a copy of the NTSC CAV Definitve Collection Box and now I'm looking for a suited player for playing them back and a capture card to digitize them. I'm doing this just for the fun of it and I don't wanna spend huge amounts of money on this little project, but I guess there might be others out there who want to the same, so I thought I'd start a brainstorming thread to collect the knowledge about it.

1) What Player to use. Sure, there are the X-Players (X0, X9), but they are almost out of anybody's reach price- and availability-wise. And since the picture undergoes digital processing afterwards anyway, is there any use to use a player that comes with all sorts of filters or would it be better to use one that outputs the composite signal without any processing? Pure or pimped, what do you think? I think the LD9 or the V8000 would do a good job, am I wrong? I might be wrong, but with the tools available today (AfterEffects plugins, AviSynth, etc) a high quality 3D-comb-filter seems rather redundant to me. And using the RGB output is supposedly not the purest way of capturing the video since it's stored on the LD in composite format and then transformed Chroma/Luma separated inside the player to conform it to RGB, am I right?

2) What capture cards are suited for the job? I'm thinking about getting a Blackmagic Design Intensity card for the job, it supposedly works very well with Final Cut Studio 2 and has great quality A/D converters.

3) What codec/resolution to capture in? I'm thinking about capturing in NTSC resolution at 480i/29,97fps, the pulldown will then be removed after capture, obviously. I'd like to use ProRes422 on my MAC, with post-processing done scene-wise uncompressed 4:4:4 on both Windows and MacOSX.

4) Up-converting to HD. Sure, there isn't too much resolution on the LDs to begin with, however, I'd like to have a BluRay25 with some offline-rendered upconversion instead of a DVD that's being upconverted to my display-size in real-time. There must be some benefit of doing it that way. What kinda up-scaling algorithms would you prefer? I recently discovered a Shareware program called VideoEnhancer which does a pretty good job, at least I thought so, until I compared the output with of Lanzcos4Resize and it made no difference whatsoever? Any thoughts on that?

5) Multi-pass. I heard Max_Rebo saying on the V8 thread that there's a way to use multi-pass capture to decrease analog noise. How's that done? And can the same be done to increase the detail-level of the capture?

6) Things not yet considered. Any input?

Shoot (first) guys, I'm really interested in how YOU would do it!

 

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You'll probably get more responses in the "technical discussions" forum. 

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Oh, you're right! I'm sorry, could a moderator please move this thread over there? Thanks.

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1. It has been said that the V8000 is a very good choice; no fancy features like dual side play or AC3 output, just a clean composite output.

You have to put the video through a comb filter at some point in the capture process. In my experience, it is preferable to use a high-quality 3D comb filter, rather than using a basic filter then trying to fix the resulting rainbows and dot crawl in software.

2. I think I read on Doom9 somewhere that the Intensity Pro is designed primarily for HDMI capture, and the analogue capability is almost an "afterthought". Looking on their website I can't see any specs for what kind of comb filter is on the card. The X0 project used the PDI Deluxe, but  this card is quite old now.

Possibly the ideal would be to use a video scaler to convert the composite signal into component outputs (look on ebay, scalers are not as important in the digital age), and get a basic card that can capture component (Compro VideoMate series have 10-bit ADCs, the E500 can capture component).

3. Capture 720 x 480 using a lossless codec.

4. Avisynth/NNEDI.

5. It's a simple theory - analogue noise adds a random variance to the image, if you average out a number of different captures then you - in theory - end up removing the random noise and keeping the detail on the laserdisc.

Unlike other noise reduction methods, this should not be destructive - traditional spatial algorithms may destroy fine texture, temporal algorithms can cause motion smearing (which admitted can be reduced using more advanced "motion-compensated" filters, if you wanted to go that route instead).

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Thanks for your input!

a) I'm glad you "warned" me about the Intensity card, however, I still have a hard time thinking about the necessity of a comb filter. Doesn't it sorta destroy the field order (in other words - deinterlace) and therefor make the process of IVTC somewhat harder?

b) I'm sure I'll try to get a V8000, it seems to be a great choice. THANKS!

c) I'm a little familiar with the process of denoising. However, if you just average out 3 different captures, don't you just end up with a the "average" noise of them? How would this go about efficiently?

 

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 (Edited)
Moth3r said:

Possibly the ideal would be to use a video scaler to convert the composite signal into component outputs (look on ebay, scalers are not as important in the digital age)

 

From what I can find on the net, the Faroudja 'video scalers' and video processors all seem to upsize the image and change it in some way and usually to a higher resolution.  The best I could find convert to 720P output as a minimum which I guess is not ideal considering LD is interlaced.  I thought the idea was to do the scaling and deinterlacing in s/w as this can have better results than scaling in real time.  The only devices that I could find that did not seem to scale the image were the two combfilter/chroma decoder devices that you mentioned in the X0 forum.

 

Has anybody used or owned any of these devices and can comment on all of this stuff please?

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@resonator:
A "comb filter" simply separates the Y (luma) and C (chroma) data from a composite video signal. It does not deinterlace. (Sometimes interlacing artefacts are referred to as "combing" - confusingly, this is in no way related to a comb filter!)

Since digital video is stored as YUV or RGB, an analogue composite signal must be separated into Y/C before it can be digitized. 

@Orinoco_Womble:
This might be a useful read:
http://www.videohelp.com/forum/archive/hardware-video-processors-and-filters-t239205.html

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Think of a "comb filter" as something that, basically, combs through the higher frequencies, separating them out.

 

Ya see...

 

The luminance (B&W) signal clumps up at higher frequencies, leaving lots of gaps. So, when they invented color tv, they forced the color signal to clump up into frequencies that would fit in those gaps. It didn't work very well, until the integrated-circuit age brought us comb filters.

 

TV and Video Comb Filters .

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