How is a Star Wars laserdisc ripped?

Author: electrictroy
Date: 4-May-2005, 9:49 AM

Author: electrictroy
Time: 4-May-2005 9:49 AM
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I assume it involves running the LD's composite output through a COMB filter, to separate the elements into component video, and then feeding it into a computer for analog-to-digital conversion?

Or is it more complicated than that?

Troy Heagy
Electrical Engineer

Author: MeBeJedi
Time: 4-May-2005 11:00 AM
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Actually, it's far easier than that. LD's are a composite signal, so your best bet is to use the composite output. Now, you may or may not know (and this is also for anyone else that doesn't) that the composite signal is eventually upconverted to S-video, then component (which is the DVD format), then RGB for most display devices - so one would ask: why not use one of these better connections?

Well, very few LD players have RGB, and none had component (the combo LD/DVD players did have component - but it was used solely for the DVD signal. That being said, I know of one person who actually connected the LD output to the component-video circuitry, but this procedure is not recommended for the faint of heart.)

So, what about the S-video? Well, you mentioned the comb filter, which shows some sophistication. Now, if you use the S-video of your LD player (assuming it has such - some do not), then you are using a comb filter that is approximately the same age as your LD player, which could be up to 30 years old. Chances are that the TV and/or computer video card that you are using to display or capture your LD signal is much newer, and thus its comb filter is more advanced.

I've also heard mention (though I've forgotten the specifics) that the S-video signal from some LD players has been reprocessed or overprocessed and produces a less-than-spectacular S-video signal.

Point being, you are better off using the comb filter in your TV or computer versus that of the LD player, but you should at least capture a small segment from each output and compare them to see if you notice a difference, and if so, which output produces a better picture to your eye.

MeBeJedi: Sadly, I believe the prequels are beyond repair.
JediRandy: They’re certainly beyond any repair you’re capable of making.

MeBeJedi: You aren’t one of us.
Go-Mer-Tonic: I can’t say I find that very disappointing.

JediRandy: I won’t suck as much as a fan edit.

Author: electrictroy
Time: 4-May-2005 11:17 AM
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I'm surprised that Laserdisc uses a composite signal to store the video.

Even lowly VHS stores the video as 2 separate signals (s-video). I wonder what led the Laserdisc engineers to the "composite storage" decision?

BTW, I still have a couple of RCA Selecta-vision "video-records" in my basement (they use needles, not lasers). Those have really deteriorated over-the-years... clearer than VHS, but with lots of noise in the signal.
troy

Author: MeBeJedi
Time: 4-May-2005 11:36 AM
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I thought only S-VHS did that?

Regardless, VHS is half the resolution of LD, so it could never compete anyways.

MeBeJedi: Sadly, I believe the prequels are beyond repair.
JediRandy: They’re certainly beyond any repair you’re capable of making.

MeBeJedi: You aren’t one of us.
Go-Mer-Tonic: I can’t say I find that very disappointing.

JediRandy: I won’t suck as much as a fan edit.

Author: electrictroy
Time: 4-May-2005 1:00 PM
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"Every VCR records as separate luminance and chrominance" although only Super VHS and Hi-8 provides those two signals to the outside world.

http://www.dansdata.com/video.htm

Author: MeBeJedi
Time: 4-May-2005 1:28 PM
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Ah, I get you now.

MeBeJedi: Sadly, I believe the prequels are beyond repair.
JediRandy: They’re certainly beyond any repair you’re capable of making.

MeBeJedi: You aren’t one of us.
Go-Mer-Tonic: I can’t say I find that very disappointing.

JediRandy: I won’t suck as much as a fan edit.