kz08+@andrew.cmu.edu (Ken Zuroski) (07/09/90)
Hi: First of all, I'm not a technical person, so please forgive any inappropriate terminology I might use or any other such denseness on my part. I heard on the radio the other day that instead of using conventional cassette tapes to store commercials and other such clipettes, radio DJ's are beginning to use 3.5 inch microdiskettes instead. It was my understanding from the news I heard that the information was not stored digitally, but rather was analog, much like conventional cassette tapes. The advantage in doing things this way was that they could program a computer (I think they mentioned a macintosh) to play clipettes at appropriate times, do special effects, etc. Can anyone tell me if this is a common thing, that is, storing analog information (or rather, storing information in analog) on media conventionally used to store digital info? Obviously the hardware needed to read/store such analog information would differ from conventional disk drives; does anyone know which manufactures make such equipment? Also: storing a song or a picture in analog takes up much less media space compared to digital, is that not true? (Of course at the expense of many other things, I am aware . . . .). Thank you for reading and for any information you can give me. --Ken Zuroski
hbg6@citek.phx.mcd.mot.com (07/10/90)
In article <Iaa=_e200WBKE57EV0@andrew.cmu.edu> kz08+@andrew.cmu.edu (Ken Zuroski) writes: > >Can anyone tell me if this is a common thing, that is, storing analog >information (or rather, storing information in analog) on media >conventionally used to store digital info? Obviously the hardware We evaluated an inspection system in our plant about 8 months ago which stored frames of video onto a 3 1/2" hard drive. The idea was to store an image of a perfect circuit board in the system, then electronically compare it to a live image of the same board type. It's difficult to get any hard technical details from a salesman but as I understand it, one frame takes up one track on the media. One field is on side one and one field is on side two. As the disk rotates, it switches from one side to the other to construct the full frame. They also had a sharp security system for a guard gate where a person would 'swipe' his badge through a reader and the system would display his picture on a monitor in the guard station. Picture no match - person no enter. If you need it, I can dig out the file and give you their company details. John Schuch ..................................................................... All opinions expressed are mine and not Motorolas, their loss. .....................................................................
sreekanth@rgb.dec.com (Jon Sreekanth) (07/24/90)
In article <13183@mcdphx.phx.mcd.mot.com>, hbg6@citek.phx.mcd.mot.com writes... >In article <Iaa=_e200WBKE57EV0@andrew.cmu.edu> kz08+@andrew.cmu.edu (Ken Zuroski) writes: >> >>Can anyone tell me if this is a common thing, that is, storing analog >>information (or rather, storing information in analog) on media >>conventionally used to store digital info? Obviously the hardware > >We evaluated an inspection system in our plant about 8 months ago which >stored frames of video onto a 3 1/2" hard drive. The idea was to store an >image of a perfect circuit board in the system, then electronically compare >it to a live image of the same board type. > >It's difficult to get any hard technical details from a salesman but as I >understand it, one frame takes up one track on the media. One field is on >side one and one field is on side two. As the disk rotates, it switches from >one side to the other to construct the full frame. > John, I tried sending you email, but it bounced. About the inspection system you mentioned : I assume it was storing digitized (compressed) images on the hard disk, in which case it's just conventional technology ? Or was it actually a hardware-modified drive ? Thanks, / Jon Sreekanth US Mail : J Sreekanth, 79 Apsley Street, Apt #7, Hudson, MA 01749 Digital Equipment Corp., 77 Reed Road, HLO2-1/J12, Hudson, MA 01749 email : sreekanth@rgb.dec.com Voice : 508-562-3358 eves, 508-568-7195 work
hbg6@citek.mcdphx.mot.com (07/25/90)
In article <13807@shlump.nac.dec.com> sreekanth@rgb.dec.com (Jon Sreekanth) writes: > >In article <13183@mcdphx.phx.mcd.mot.com>, hbg6@citek.phx.mcd.mot.com writes... >>It's difficult to get any hard technical details from a salesman but as I >>understand it, one frame takes up one track on the media. One field is on >>side one and one field is on side two. As the disk rotates, it switches from >>one side to the other to construct the full frame. > >John, > >I tried sending you email, but it bounced. >About the inspection system you mentioned : I assume it was storing digitized >(compressed) images on the hard disk, in which case it's just conventional >technology ? Or was it actually a hardware-modified drive ? > >Thanks, >/ Jon Sreekanth > As overwelming as the temptation to dismantle equipment at trade shows is, I seem to be able to restrain myself, most of the time :-) Not being able to peek inside I have to go by what the sales guy said. He lead me to believe that they retained the drive sub-controller to run the heads and spin the platters but the analog lines from the heads were DIRECTLY connected to an external analog video board. I am inclined to believe it given their demonstration. The badge system works by swiping a card through a reader. The number of the card determines which picture is displayed. The time lapse from swipe to display on the CRT was about .1 seconds (judged by eye). It would seem to me that that's about enough time to swing the heads out to the track but not long enough to read a big block of data and cram it through a flash converter. They did not seem to be real willing to get into the nitty-gritty tech. details. Now if I could just figure out why Email can get to me! Thanks, John Schuch ..................................................................... . All opinions expressed are mine and not Motorolas, their loss. . .....................................................................
jack@focsys.uucp (Jack Houde) (07/25/90)
In article <13269@mcdphx.phx.mcd.mot.com> hbg6@citek.mcdphx.mot.com writes: >In article <13807@shlump.nac.dec.com> sreekanth@rgb.dec.com (Jon Sreekanth) writes: >> >>In article <13183@mcdphx.phx.mcd.mot.com>, hbg6@citek.phx.mcd.mot.com writes... >>>It's difficult to get any hard technical details from a salesman but as I >>>understand it, one frame takes up one track on the media. One field is on >>>side one and one field is on side two. As the disk rotates, it switches from >>>one side to the other to construct the full frame. >> We looked into this option some time ago vis-a-vis putting video information on a floppy diskette. Needless to say it went nowhere real quick given a floppy's dynamics. A hard disk on the other hand might hold promise. Most disks rotate at 3600 rpm which means that it would rotate once every 60th of a second, exactly one field time! The only problem is if the media can handle any sort of reasonable bandwidth (ie 640 x 480, 256 x 256 or higher resolution). >>About the inspection system you mentioned : I assume it was storing digitized >>(compressed) images on the hard disk, in which case it's just conventional >>technology ? Or was it actually a hardware-modified drive ? >> >Not being able to peek inside I have to go by what the sales guy said. He >lead me to believe that they retained the drive sub-controller to run the >heads and spin the platters but the analog lines from the heads were >DIRECTLY connected to an external analog video board. I am inclined to I seriously doubt this. You need to work out all sorts of biasing issues here. >believe it given their demonstration. The badge system works by swiping >a card through a reader. The number of the card determines which picture >is displayed. The time lapse from swipe to display on the CRT was about >.1 seconds (judged by eye). It would seem to me that that's about enough You can move a 752 x 484 image onto an SCSI disk in about 1 second (DOS) which is 363968 bytes. .1 seconds would allow 36396 bytes which is lower resolution (142 x 256 if we assume an interlaced image) so it could still be digital. >time to swing the heads out to the track but not long enough to read a big >block of data and cram it through a flash converter. > It takes 1/60th of a second to cram it thru the flash. I would be interested in getting more information on these people if its available. Thanks.
hbg6@citek.mcdphx.mot.com (07/26/90)
OK, enough conjecture! I dug out the file and REALLY read the description of the video on hard drive system. Here are the highlights: Images stored 1230 interlace, 2460 single field Image Full screen, monochrome, single field or interlace Storage media 20 Meg hard drive Access time 65 Ms Disk Organization 1 track per video field Recording Method Bit Cell Modulation Resolution 512 X 256 field mode, 512 X 512 interlace mode Recording time 16.7 Ms Grey scale analog equivalent to 256 grey shades Refresh Continuous "No frame grabber required, video signals are directly recorded" "sequential or random access and display of images [for animation]" "accepts NTSC, PAL, CCIR, SECAM" "stores equivalent of 300 megabytes of video information" The company data is: Image Research Corporation 8260 East Raintree Scottsdale, AZ 85260 (602)998-1113 If you call, tell them a friend saw it at the Mesa trade show last year :-) ( I'm not affiliated with this company but my brother runs the trade show) Now; can someone tell me what bit cell modulation is? Thanks, John Schuch ..................................................................... . All opinions expressed are mine and not Motorolas, their loss. . .....................................................................