Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site nicmad.UUCP
Path: utzoo!linus!philabs!cmcl2!seismo!uwvax!astroatc!nicmad!brown
From: brown@nicmad.UUCP
Newsgroups: net.video
Subject: Re: Gen Lock
Message-ID: <366@nicmad.UUCP>
Date: Fri, 27-Sep-85 10:31:51 EDT
Article-I.D.: nicmad.366
Posted: Fri Sep 27 10:31:51 1985
Date-Received: Tue, 1-Oct-85 11:15:30 EDT
References: <3475@utah-cs.UUCP>
Reply-To: brown@nicmad.UUCP (Mr. Video)
Organization: Nicolet Instrument Corp. Madison WI
Lines: 55

In article <3475@utah-cs.UUCP> crum@utah-cs.UUCP (Gary L. Crum) writes:
>I would like someone to define "gen lock", and perhaps describe some existing
>hardware devices that use gen locked video images for special effects.

It is the means by which ALL of the video equipment in a TV studio, TV network,
pay TV channel, TV production house, etc.,  keeps all of the equipment in sync.
Since the video signal is very time-base dependent, a single source of the
TV video sync signal is used.  This piece of equipment generates the vertical
and horizontal sync pulses.  It also generates some other sync sugnals, such
as the vertical interval window, the horizontal sync window area, etc.

This piece of equipment allows all of the cameras to be in phase, the character
generator to be in phase with the cameras, video decks to be in phase (when
played back), so that they all can be put through a video switcher board.

Genlock is NOT required to just play a video deck onto a TV set.  It is
needed in order to do ANY kind of video mixing or special effects.

>Commodore has recently introduced a new 68000 based microcomputer with nice
>graphics capability, and this is one of their accessories for it:
>(the following is from Commodore's 16-Sep-85 suggested retail price list)
>
>Part #  Product		Description				Price	Avail
>-----------------------------------------------------------------------------
>1300	Genlock		An interface to allow the computer to	249.95	Dec
>			synchronize to external video sources
>			such as VCRs and laser disks for increased
>			graphics cababilities.
>
>Do you think that this would allow the Amiga to display and manipulate
>external video images on the computer's own screen, e.g., TV in a window?

Yes, I suppose that it could.  But the Amiga will need a Analog to Digital
converter first.  Without seeing the complete description of the 1300,
it is kind of hard to determine what they meant it for.  One use would be
to be able to create graphics images so that they could be put through
a video switcher, allowing mixing of the Amiga's graphics images with
other signals.  The ideas of this are really up to the imagination of the
video user.  But, it is the starting point of being able to mix the Amiga's
TV signal with other signals.

One last point to remember about the Amiga.  The graphics are SO MUCH BETTER
than what you can get onto a regular TV screen.  Mixing the Amiga with regular
video may lead to disappointment.  Just keep that in mind.

>Additionally, while deciding what VHS VCR to purchase (I eventually chose
>the old Magnavox VR8445SL for $699), I noticed the AR8214BK Sync Coupler,
>that provides Gen Lock capability for the Magnavox VR8282 video camera.

Same deal with the camera, as with the Amiga.  A means of allowing the
camera's signal to be mixed with other signals.  Very few home cameras
have the ability of being genlocked to the outside world.
-- 

Mr. Video   {seismo!uwvax!|!decvax|!ihnp4}!nicmad!brown


Brought to you by Super Global Mega Corp .com