Extracting Digital Video from LaserDiscs?

americanatavist asks: "I was wondering how feasible it would be to digitally copy LaserDisc movies to DVD. Clearly this would require the standard suite of tools to make a DVD. What method would yield the maximum level of quality? Is it worth the effort to find a means of extracting the digital information using an LD-ROM drive, or would the S-video from a regular LD player suffice?"

Not digital

[alienw]

Laser discs are actually analog. So you can't copy them to DVD directly.

Sell them.

[jpmkm]

Laserdiscs video is analog so you cannot digitally extract it. If you would rather have DVDs then sell your laserdiscs and buy the DVDs. Though I know some movies were released on laserdisc but not on DVD(Johnny Got His Gun comes to mind).

Re:Sell them.

[grotgrot]

then sell your laserdiscs

Sadly there is almost zero market for selling laserdiscs. Many of those on eBay don't even get bids. For those that do get bids, add in the shipping costs and the result is similar in price to DVDs so only few people will buy the disks.

An even bigger problem is the lack of players. Due to the size and weight of the discs, the players do start acting up over time. That makes second hand players a very dicey decision.

Two years ago I needed a new player due to the death of my old one after 7 years of service. The only new one available was the Pioneer DVL-919 at around $1000. That buys a lot of DVDs. Fortunately I managed to get a used player for $50 from my local AV store, but when it dies I'll give up on Laserdisc.

I have about 350 discs, and it will be a sad day when I can no longer watch them. DVDs are a lot more convenient, especially from Netflix :-)

Analog Composite Video, Digital Audio

[toren]

As many others have pointed out, LaserDiscs have analog video. Also of note is that they store composite video, so a LaserDisc player with an S-Video connector is not necessarily better than one without, as your capture card may do a better job than the player of converting composite to S.

The audio on LDs is (except for the very old discs) digital: 16-bit 44KHz PCM, just like CDs. Many newer discs contain AC3 audio (16-bit 48KHz multichannel Dolby Digital) or dts audio, but in either case you'd need a player that supports it.

For convenience, you can't beat hooking the player up to a FireWire DV media converter box. But for the best quality transfer, I recommend:

Video: raw analog capture card; WinTV dbx or preferably PixelView X-Capture, an incredible card for ~$40.

Audio: get an audio card based off of the CMI8738 chipset that has digital in/out. These can capture an externally-clocked digital signal without altering it at all. I've used one of these to capture the 5.1 Dolby Digital stream off of a LaserDisc and (with some slight massaging of the stream) put it on a DVD without recompression. Even if you're just dealing with the 44KHz stereo PCM that's on most LDs, this will get you a cleaner signal that other options. If you're planning on grabbing the AC3 audio, you'll need an AC3-RF demodulator, or a preamp that will take an AC3-RF signal and output SPDIF or TOSLink to the soundcard.

I've successfully used this to get top-notch transfers of my own LaserDiscs to DVDs. Good luck!

I have done LD transfers

[GreatDrok]

LD uses frequency modulation to store an analogue signal on an optical disc. The lengths of the pits and lands correspond to the wavelength and by varying that length (modulating) you can store an analogue signal on an optical disc. LD was originally shown in the early 70's and commercially appeared in the late 70's. Originally it had a high quality analogue stereo sound track to go with the analogue video. Later a 16 bit 44.1Khz PCM sound track was added. On NTSC discs this could co-exist with the old analogue sound but for PAL discs the video signal takes up too much bandwidth to allow this and so the analogue audio was dropped in favour of the PCM audio. Quality wise, there wasn't that much in it, LD analogue audio is very good, much better than VHS Hifi sound. Discs also come in two flavours, Constant Linear Velocity (CLV) and Constant Angular Velocity (CAV). CLV discs play for roughly twice as long per side (about 1 hour) but lose the trick play features of CAV (slow motion and pause) unless there is a digital field buffer in the player. The trick play CLV digital effects are not as nice as a true CAV disc though.

Now, there has been talk of s-video being better to capture from the LD. Others have suggested RGB. Well, the answer is that neither is best. LD video is stored as composite video and any LD player with an s-video or RGB output is extracting that from the composite signal. Depending on the quality of the player you may be better just using the composite signal and using a high quality demodulator. The most modern LD players included advanced 3 line or 3D comb filters to separate the chroma and luma and give an s-video output that looked better than the quality of consumer TVs. Where digital field effects are available it may not be possible to get at the true composite video signal depending on the design of the player as some recombine the internal digital signal extracted from the disc for these effects back into analogue s-video and composite signals. Some players even offer the output as RGB but the picture quality is pretty poor.

Another problem with LDs is that they suffer from chroma noise. Generally the picture quality is very good, way better than SVHS. Resolution is 425 lines (NTSC) or 440 lines (PAL). Remember this has little to do with scanlines. Lines of resolution is a measure of how many lines you can resolve for example on a test card like those provided on Video Essentials. SVHS maxes out around 400 lines so is almost as good and VHS sits at 240 lines. DVD manages around 480 lines so looks a little clearer depending on the transfer. LD looks much better than VHS or SVHS because it has more bandwidth for the chroma (colour) portion of the signal than the VHS formats. The difference is apparent when you make an SVHS tape of an LD, it looks muddier and less colour rich. Betamax recordings look significantly better in this respect. However, some LDs were not great transfers and suffered noise in the colour signal and this appears particularly in the blues which sometimes flicker badly. The Aladdin CAV LD set for instance is very bad for this. Conversely the THX CAV LDs of the Star Wars Trilogy are amazingly clean. The noise levels will affect your ability to get a good digital transfer.

The highest quality LD players were notable for increasing detail through the use of high quality video processing to reduce chroma noise. The Pioneer Elite series LD players were very good in this respect and if you are going to do a transfer you need to get one of those. Budget LD players still look good but may be more noisy.

Ordinary computer capture cards (things like WinTV PCI) are poor at best for this. You may be better getting your hands on a stand-alone DVD recorder and going with that. Of course, you also have the issue of getting the audio. Some LDs contain Dolby Digital or DTS sound. DTS sound is available on the standard optical digitial audio out but DD sound comes from an RF modulated connection that you can't just stuff into a d

Re:doing this with origional STAR WARS trilogy

[vrai]

Someone's already done this. There are torrents around of LD->DVD rips of the original trilogy, sans Lucas' updates. Not that I've downloaded them of course - because, obviously, I'd never engage in the theft of copyrighted material. However for those more morally flexible than myself the torrents are out there.

Practical and usefull advice

[nedron]

I've done this many times for LDs that have not as yet been (and probably never will be) released on DVD.

I have over 1000 Laserdiscs, and two very good players (one brand new in the box, waiting for the day my main one dies). However, a couple of the rare discs that I really like have started to exhibit some speckling, so I've transferred those to DVD.

As others have pointed out, the video track on LDs are actually analog, so the setup is very simple (assuming you don't want to extract the digital audio from the disc). Here's how I do it:

• S-Video and analog R/L outputs of the player connect to the inputs of a Sony DVMC-DA2 Analog-to-DV Firewire bridge.
• The Sony DVMC-DA2 is set for 16-bit audio and the Firewire output of DA2 is connected to my Apple G5.

That's pretty much it. Now, you just start recording in whatever app you use to capture DV, and start the player.

Note that you should be sure to select the correct audio mode on the LD player if you're capturing a disc with Dolby Digital audio. One of the major failings of DD on LD (which DTS didn't have) was that they sacrificed one of the audio channels to contain the DD bitstream.

You may also want de-interlace the footage in your capture app before transcoding for DVD.

-David