Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!IRO.UMontreal.CA!martin From: martin@IRO.UMontreal.CA (Daniel Martin) Newsgroups: comp.sys.amiga Subject: Re: Multimedia Keywords: CD-ROM, Technical, WORM, Magneto-Optical drives Message-ID: <1990May4.023632.2091@IRO.UMontreal.CA> Date: 4 May 90 02:36:32 GMT References: <17644@snow-white.udel.EDU> <24445@pasteur.Berkeley.EDU> <984@tmiuv0.uucp> <17539@well.sf.ca.us> <5698@gollum.twg.com> Sender: news@IRO.UMontreal.CA Reply-To: martin@iros52.UUCP (Daniel Martin) Organization: Universite de Montreal Lines: 54 in article <5698@gollum.twg.com> david@twg.com (David Herron) writes: >... As others have said the only choice is the expensive route through the > CD-ROM stampers. Not that expensive. Cost per unit is vary with quatities, but go around 2.50$. Making the master cost 1000$. This is an appealing approch for software distributers. >Playing CD ROM's through an Amiga oughta be pretty simple. They just >hook up as an SCSI device and it'd require another file system. Comming soon to an amiga near you! >Wouldn't it be possible to emulate CD ROM's with WORMS? Or even these >magneto-optical drives that are starting to come out? They all have approx >the same storage capacity (600 megs). Is the data throughput approx >the same? The throughput I recall for CD ROM is 150 kbyte/sec which is >more than a bit low for video so maybe that's not right. A CD-ROM is 12cm (4.72inches) and can contain 660megs. A comparable 5 1/4 inches WORM disk can only contain 200megs [1]. No standard has emerge yet, but large disks can go over the 1 gigabyte barreer (perhaps using 2 sides reflective disk instead of transmissive ones). Informations on CD-ROMs is place in a spiral using CLV (constant Linear Velocity). To find information the CD-ROM player must first seek a track and adjust it's speed (varying from 00-530rpm) find the correct position of the spiral track and then find the correct sector. Maximum delay can take over 1 seconds. The new magneto-optical drives seem to be the future. You can write them, they are inexpensive and slowest ones can compare with floppy drives. Transfer rates are in the 1-5 Megabit range. >So you write it onto a WORM or mag-opt and test away. Or just buy a big HD. 660 megs are 3000$ and 1.2 gigabyte 5000$. I wouldn't be surprised if those go under 1000$ in a 4 year period (recent byte pronostic :-) ). > ><- David Herron, an MMDF weenie, Daniel Martin. P.s Where the world is comming to - mailers gave me: Do you wish to subscribe to alt.sex.aluminium.baseball.bat? Reference - [1] Luther, Arch C., "Digital Video in the PC Environment", Mc Graw Hill, pp. 330, 1989. -- // Daniel Martin Universite de Montreal \\ // MediaLab, ca vous regarde! C.P. 6128, Succursale A, \\ \\// Mail: martin@IRO.UMontreal.CA Montreal (Quebec), CANADA, \\// \/ UUCP: ..utai!mcgill-vision!iros52!martin H3C 3J7, Tel: (514)343-7009 \/