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Old 31st December 2001, 04:08   #1  |  Link
swdefdvd
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NEW PROJECT: Star Wars Trilogy The Definitive Collection Laserdisc To DVD Project

Help needed. Go here for more information.

http://www.geocities.com/swdefdvd/

Any help welcomed.
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Old 2nd January 2002, 08:46   #2  |  Link
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Digital transfer

Hi, good to see someone else is ripping the starwars collection. There have been several people to release this collection already on divx but a dvd would definetly be nice.

However if you go ahead with the project i recomend you look into transfering the LD video data digitall to you pc rather than though an analouge capture device. I've only ever seen this happen once and that was when 'funny' (taiwan dvd ripper) released thunderbolt (jackie chan movie) on dvd. When you watched it, it was obvious that the video had been digitall sourced - how he/she/they did that is beyond me. But sice LD's have the same optical technology as cd's it should be possible to make a big cd-rom drive capable copying the laserdisc mpeg1 file to you hdd for re-encoding.

If you can figure out how to connect a LD player up to a pc digitally let me know as this is one thign i've always wanted to do.
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Old 2nd January 2002, 14:51   #3  |  Link
Peter von Frosta
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I'm very confused, how do you want to make a digital copy from an analog laserdisc?
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Old 2nd January 2002, 18:35   #4  |  Link
swdefdvd
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You are correct. Laserdisc video is analogue. The audio is digital. I'm capturing the video through a Dazzle Hollywood DV Bridge using the Microsoft NTSC video codec.

Keep checking the site for an update on this.
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Old 2nd January 2002, 20:32   #5  |  Link
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From my understanding Laser Discs contain ultra high bitrate Mpeg 1 video files hence digital. If someone can prove otherwise i willl gladly concede.

I'd propose to make a digital copy by replacing certain components within a laser disc with those of a pc-cdrom so it can be read through ide/scsi interface. This should work sice a LD is the same make up as a cd-rom only larger.

Alternatively there must be existing laserdisc players for PC's but they're probably hidden away at movie studios or deep within thailand, and near impossible to get a hold of.

The reason to keep everything digital is because you definetly loose quality when converting digital - analouge - digital. Also the audio should turn out slightly crisper as well. ***EDIT*** Ignore that comment if you are already capturing audio through spdif.

Last edited by gooki; 2nd January 2002 at 20:54.
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Old 2nd January 2002, 21:35   #6  |  Link
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Video material on a laserdisc is usually digitally remastered but when it is placed on a disc it is analogue.
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Old 2nd January 2002, 22:20   #7  |  Link
gooki
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Then why do laser disc players have mpeg1 decoder chips built into them? And how can you have chapters on a laserdisc and but not have a digital video source?

***EDIT*** Typo

Just to clear thign up - the two of you agree that DVD video is stored digitally right?

***EDIT*** Lol looks like i fucked up - probably should have done some more reading before i open my mouth. Will post a pic later of a laserdisc 2 dvd conversion, just so you know how high the quality can get if done right.

Last edited by gooki; 2nd January 2002 at 22:37.
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Old 2nd January 2002, 23:29   #8  |  Link
Antti
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Video on laserdisc is stored in analog form, using frequency modulation. The technology is from 1970's, there were no mpeg or any digital video then (in regular use).
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Old 2nd January 2002, 23:38   #9  |  Link
swdefdvd
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I look forward to seeing the picture and any information on how to do it right. Cheers!
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Old 2nd January 2002, 23:51   #10  |  Link
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I still have some of the promotional material circa 1980 advertising and explaining Laser Disc.
According to this material, the picture is stored in an analogue format but by no method as advanded as Frequency Modulation.
This literature claims (and gives diagrams) that each frame of the movie is in fact stored as a tiny image in the pits of the disc which has a laser shone through it and it is magnified onto a camera inside the player. This seems somewhat bizzare but is how Philips claimed it was done around 1980.
The audio was of course stored digitally using the same system which was later used for Compact Disc.
With this in mind, surely the purest way to capture the image from a Laserdisc would be to capture the signal from the camera inside the player and digitise it straight from there...
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Old 3rd January 2002, 01:03   #11  |  Link
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yorkie,
Can you scan in the promotional material and make it available. I would like to see what it says. It seems kind of odd.

pi
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Old 3rd January 2002, 01:16   #12  |  Link
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How laserdiscs work

http://www.laserdiscarchive.co.uk/la...e_produced.htm
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Old 3rd January 2002, 01:47   #13  |  Link
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I Don't have a scanner i'm afraid. It's possible that this may be inaccurate informartion as around 1980 I don't think the concepts used for Laserdisc were something that the general public could have really got their heads around. This may have been simplified (dumbed down) for public comnsumption.
The best I can do is describe the drawings on the leaflet..

It shows a picture of a Laserdisc and a small portion is circled and enlarged (supposedly) to show what happens. It shows several tiny images on the disc. A sepaerate diagram shows one of these images on the disc having a laser fired through it and being magnified up against (what i assume to be) a small tube camera.
As i said, this seems strange as what happened if the unit became jolted and the beam no longer aimed correctly?
Would it have been possible to have got a camera of adequate quality inside a unit this size with late 1970's technology? I doubt it...
I pesonally think the FM method is more feasible as I can actually figure out ways in which this could have been done and given excellent quality (remembering that HI-FI sound on video tapes is analogue FM). It's almost like the FM signal on the disc is simply an analogue waveform similar to the groove on a vinyl record.
Also worth remembering that early TV recordings were made on records. http://www.dfm.dircon.co.uk/ So the idea of analogue recording on a disc is by no means a new idea.
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Old 3rd January 2002, 05:31   #14  |  Link
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I think the brochures must be *very* dumbed down. Remember that a laserdisc is two sided. The laser doesn't shine 'through' the disc, and if it did, it'd pick up two 'pictures'.

I'm virtually certain that a laserdisc basically contains the original broadcast FM modulation encoded as pits of varying length on the disc (as hinted at in the 'producing a laserdisc' article - too bad there isn't a 'how playback works' article). The vertical ramp signal might be removed on the disc and added back by the player, but the concept of directly recording the modulation of the FM signal is the same, and much more in keeping with the capabilites of 70's technology. The laser pickup just has to be a very fast intensity sensor.
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Old 3rd January 2002, 21:02   #15  |  Link
Antti
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Analog television broadcasting is usually AM, this applies to both PAL & NTSC. In SECAM color subcarriers are frequency modulated.

For Laserdisc technology FM is natural, because the pits on a disc contain information about zeroes of modulated signal. To be more accurate, that is pulse width modulation. The player reconstructs the FM signal and demodulates it.

In theory, if you could transfer the PWM signal directly to a computer, you could most accurately regenerate the original video signal, using digital signal processing for demodulating and color decoding. I doubt this is possible, you would have to hack a LD player and use a high frequency A/D converter and then write software to transfer the signal to an ordinary form.
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Old 3rd January 2002, 21:30   #16  |  Link
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I must tell that I found this whole thread, and especially title as ridiculous.

To achieve some decent quality DVD from Laserdisc you will need very expensive equipment, but still be limited with (non)quality of Laserdisc (player).
Of course we can dream about making something better always...

I'm quite sure that Lucas will faster launch regular DVD's.

Btw. there is all 3 part on Chinese DVD's. It's taken from Laserdiscs.
Quality is aprox. as good VHS.
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Old 4th January 2002, 05:32   #17  |  Link
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When I capture from LD to my PC, I use a Sony DVMC-DA2 "Media Converter".. The end result is a 720x480 DV file with 48kHz audio. Excellent quality. Looks much better than those example screen grabs from the website. I use the MainConcept DV codec to work on the resultant files in VirtualDub.
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Old 4th January 2002, 11:28   #18  |  Link
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Re:

Quote:
Originally posted by ppera2

I'm quite sure that Lucas will faster launch regular DVD's.
I wouldn't be to sure of that. I remember hearing that Lucas will not be releasing any of the original trilogy on DVD until he has completed the current trio of films. Something about not wanting to split his focus between projects. This means they probably won't be out until after 2006.

Knowing Lucas, I wouldn't expect a DVD from the original trilogy until 2008. Perhaps it will be an entire episode IV,V,VI set or he could string out the releases until 2010, or maybe 2012. but I could be wrong.
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Old 4th January 2002, 16:49   #19  |  Link
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Back to the Future series, and Indiana Jones series won't be available anytime soon either.

Incidentally, I've done LD captures on my lowly WinTV card and encoded them to SVCD. It required a bit of heavy filtering in vDub, and results weren't perfect, but it was much better than VHS (especially a 20 year old VHS).
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Old 5th January 2002, 08:20   #20  |  Link
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5.1 Starwars Surround

Personally I think this whole situation is sick, and Lucas is a dick for not letting his fans have dvd's. I haven't read the specifications but I believe the video is analog and the audio is same as CD. Isn't it possible to record an analog signal digitally. Anyway, I'm sure there has to be a way to record the sound digitally, yet the video will always look analog. Thats too bad because I've seen LD... Yet a 5.1 Dolby Digital sound track would be nice to go along with that analog captured signal. Anybody think they could capture that?
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