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Xref: sserve comp.sys.ibm.pc.hardware.video:4223 comp.windows.x.i386unix:7540 comp.os.386bsd.misc:1989 Newsgroups: comp.sys.ibm.pc.hardware.video,comp.windows.x.i386unix,comp.os.386bsd.misc Path: sserve!newshost.anu.edu.au!munnari.oz.au!yoyo.aarnet.edu.au!news.adelaide.edu.au!news.cs.su.oz.au!harbinger.cc.monash.edu.au!msuinfo!agate!howland.reston.ans.net!europa.eng.gtefsd.com!library.ucla.edu!csulb.edu!csus.edu!netcom.com!hasty From: hasty@netcom.com (Amancio Hasty Jr) Subject: Re: Video output Message-ID: <hastyCLsz1J.GDu@netcom.com> Organization: Netcom Online Communications Services (408-241-9760 login: guest) References: <CLq9pt.Mps@cogsci.ed.ac.uk> <2kjd5f$g32@dingo.cc.uq.oz.au> Date: Fri, 25 Feb 1994 23:10:30 GMT Lines: 56 In article <2kjd5f$g32@dingo.cc.uq.oz.au> ggm@dingo.cc.uq.oz.au (George Michaelson) writes: >richard@cogsci.ed.ac.uk (Richard Tobin) writes: > >>I'm looking for some hardware that will allow me to record the display >>on a PC onto videotape (VHS/PAL). I will be running XFree under >>NetBSD. > >>What are the options for doing this? Will I have to reduce the PC >>display resolution to that of the video? I'm willing to get either an >>external adaptor or a replacement video card, so long as it works >>under X. > >Forgive me if this is wrong... Its my understanding... > >You need either a card with an explicit video output akin to the >(very expensive!) Galileo board on the SGI, or a generic sync rate >converter, which is a black box that plugs into the monitor flyleads >and performs the decimation/rate conversion and provides flyleads for >input to suitable recording/mixing media. (SVHS plug, BNC RGB+sync, whatever) > >VHS recorded tape and broadcast TV is around 15Khz. horizontal sync. >VGA is 35Khz, SVGA/Sun/Dec/Etc is 60, 65, 72, 100+ Khz. You can't get >from this to 15Khz without loosing information. Typically you either >select a zone of the screen for full pixel recording at the appropriate >width x height 1:1 or else do some kind of decimation. a 1024x768 >window cut down to the VHS is going to look ok, but definately not >PIXAR quality. It beats the hell out of pointing a camera at the screen >mind you... > >A sync rate converter for VGA->VHS is around $10k Australian. If you want >from 72+Khz its more like $40k Australian. I suspect a video toaster card >will be cheaper but quality will be an issue, as well as getting a NetBSD >driver. You can probably hire a sync rate converter from a mob doing >TV O/B production work, but you definately need to know the horizontal refresh >rate of the local monitor, and pinouts of the connectors. You can often >use Thinwire and T-pieces but remember Thinwire is 50 Ohm and TV is 75 Ohm >so you loose if the runs are too long. > > >Why not persuade SGI to loan you an Iris with Galileo, and use remote X >to get the NetBSD box to display onto the Iris which can then drive the >tapedeck directly? It'll only cost around $150k to buy the setup :-) > Or he can call up Fry's Electronic in Palo Alto, Ca. and get a video convertor box for his PC for around $150 so much for SGI :) Amancio -- FREE unix, gcc, tcp/ip, X, open-look, interviews, tcl/tk, MIME, midi, sound at freebsd.cdrom.com:/pub/FreeBSD Amancio Hasty, Consultant | Home: (415) 495-3046 | e-mail hasty@netcom.com | ftp-site depository of all my work: ahasty@cisco.com | sunvis.rtpnc.epa.gov:/pub/386bsd/X