Definitions for "Macrovision"
Keywords:  videotape, vcr, unwatchable, agc, vhs
Name of the company who developed analogue copy protection systems to prevent recording to VHS. A variant is used to prevent copying of DVD-Video discs. Macrovision also offer Safedisc(tm) copy protection for CD-ROM and SafeAudio(tm) for CD Audio.
A technology that applied to VHS tape and DVD support prevents unauthorized duplication.
Macrovision is a copy protection system designed to prevent the copying of films onto videotape. Most movies released onto DVD are encoded with Macrovision protection. Macrovision can generally be seen as a lightening and darkening of the video picture during play. Macrovision will be visible if the DVD player is piggybacked through a VCR, and also some projection monitors have a decrease in video quality if Macrovision is present, even if the video signal is not passing first through a VCR. Macrovision operates by interfering with the operation of the AGC (Automatic Gain Control) used on VCR machines.