home *** CD-ROM | disk | FTP | other *** search
- Path: sparky!uunet!ogicse!uwm.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!hp-col!fc.hp.com!rjn
- From: rjn@FC.HP.COM (Bob Niland)
- Newsgroups: rec.video
- Subject: Re: Video on standard CD's?
- Message-ID: <BxxApC.B9x@fc.hp.com>
- Date: 18 Nov 92 17:46:24 GMT
- Article-I.D.: fc.BxxApC.B9x
- References: <1992Nov18.153215.41492@ns1.cc.lehigh.edu>
- Sender: news@fc.hp.com (news daemon)
- Reply-To: rjn@FC.HP.COM
- Organization: Hewlett-Packard/WSY Ft.Collins,CO,USA
- Lines: 68
- X-Newsreader: TIN [version 1.1.8 PL6]
-
- MARC A. HARLACHER (mah0@ns1.cc.lehigh.edu) wrote:
-
- > While doing some research lately on digital audio encoding, I came across
- > something I thought was quite interesting. Standard audio CD's have the
- > capability to store video images. In fact, I have even gone to a local CD
- > shop and found a Fleetwood Mac CD that has video stored on it. These
- > discoveries have led to a number of questions. First: How does one decode
- > this video so that it can be enjoyed? Obviously we need a CD player with some
- > sort of video output. Will laserdisc players decode this video? From my
- > basic understanding, this technology was built-in to the CD coding scheme
- > developed way back when. It is different from CDV - is that right?
-
- There are several ways to put "video" on a "CD". Since your post was not
- entirely clear, here's most of 'em...
-
- CDV (aka CDV-5) - Up to 6 minutes of NTSC (xor) PAL LaserDisc full-motion
- video, plus up to 20 minutes of normal CD-DA RedBook audio.
- Requires a CD/LD "combi" player. Normal CD players can only play
- the RedBook portion. No new CDV5's have been released in the US
- since 1989, and only a few dozen titles before that. CDV5s are
- still available in Japan, some with only the video track.
-
- CD+G Uses CD-DA RedBook subcodes to store low-res still-frame video
- images and/or text. Requires a CD+G player (rare), Laser Karaoke,
- CD-I or PhotoCD player. Not capable of slow-rate, much less
- full-motion video.
-
- CD-ROM Video images can be stored in any number of open, partly-open and
- proprietary formats. DVI is one, and requires hardware assist.
- Requires a CD-ROM player, and possibly add-on video hardware. Most
- CD-ROMs are YellowBook Mode1 ISO 9660.
-
- CD-I Based on CD-ROM/XA Mode 2 Form 1. Uses compressed video and ADPCM
- audio, and requires a CD-I player (with processor and RTOS op sys).
- Currently can product low-rate low-res motion. Higher rates and
- resolutions are promised when MPEG compression hardware is
- available in 1993, but even then it will barely be VHS-quality.
-
- PhotoCD CD-ROM/XA "bridge" format. Uses proprietary Kodak compression to
- store still frames and various resolutions. Requires a PhotoCD or
- CD-I player or CD-ROM/XA drive and host software. Video output at
- player back panel is NTSC res regardless of stored res. Actual
- PhotoCD media is ablative dye-polymer CD-WORM (incremental write-
- once). No CD-ROM drives are currently available that can read more
- than the first "session" on the CD.
-
- Confused? Join the club. Only a small minority of computer professionals
- understand all these formats and their relation to one another. I have to
- believe that the general population will find it incomprehensible, and that
- there will be a LARGE number of times when people pop an arbitrary 120mm
- optical disc in their XYZplayer/drive, only to discover that the platter is
- totally incompatible with their drive and host software.
-
- I suspect this has already happened many times, as people take CD-I titles
- home and try them in their LD combi players. Bzzzt! No LD players support
- CD-I yet.
-
- If you thought people were confused by LD vs CED videodiscs in 1982, you
- ain't seen nothin' yet.
-
- Regards, Hewlett-Packard
- Bob Niland Internet: rjn@FC.HP.COM 3404 East Harmony Road
- CompuServe: 71044,2124 Ft Collins CO 80525-9599
-
- This article represents only the opinion[s] of its author, and is not an
- official or unofficial position of, or statement by, the Hewlett-Packard
- Company. The text is provided for informational purposes only. It is
- supplied without warranty of any kind.
-