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5.1 Macrovision
5.1.1 Description and specifications
What is “Macrovision”?
Macrovision is a copy prevention system developed by Macrovision Corporation.
Widely used by video sources such as VHS and DVD-Video on the market and by satellite
broadcasts, for instance, the system ensures that, by causing the automatic gain control (AGC) of
the video decks to malfunction, users will not be able to record properly the video output sources
which are protected by the system.
The AGC circuit is designed to adjust the gain of the input signals automatically and maintain the
appropriate sensitivity, and almost all consumer-use VTRs now feature it. It serves to make dark
images a little brighter and excessively light images darker and keep them this way.
While keeping the luminance and chrominance signal components of the video signals unchanged,
Macrovision’s copy prevention signals cause the AGC to malfunction by mixing signals with
non-standard levels in the vertical blanking interval. This is why the brightness of the images will
fluctuate even when the images are recorded. These signals also have the effect of causing trouble
for the sync signals and disturbances in the images.
The trouble caused ensures that content is unwatchable even when it has been copied.
What does the “color stripe” function do?
This function is part of the Macrovision standard, and it provides color stripes to overlap with the
regular Macrovision signals.
It constitutes a method of superimposing the modulated color burst signal onto the video signals,
and it is also referred to as a means of color burst copy prevention.
The color stripe function inserts thin horizontal lines into the copied images and, like the Macrovision
system, it makes the images unwatchable.
* The color stripes are provided only in the Type 2 and 3 modes of the NTSC-M and J systems.
( Macrovision specifications
Macrovision supports the TV signals of the following systems.
Its signals are superimposed onto the composite signals and Y/C signals.
• NTSC-M, NTSC-J, NTSC-443
• PAL-60, PAL, PAL-M, PAL-N, PAL-Nc
• SECAM
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• Macrovision is an option. Contact ASTRODESIGN sales representative or
your dealer.
• The Macrovision signals have different effects depending on the type of VHS
or DVD player. When using the system, please check the terms and conditions
of the agreement with Macrovision Corporation.
CAUTION
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