Technicolor - Thomson ICC19, Principles And Maintenance

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SMOOTHING AND CORRECTION OF SIGNALS Y2H, U2H, AND V2H
Signals Y2H, U2H, and V2H pass through the smoothing filters required after
digital-to-analogue conversion, and are injected at 26, 30, and 28 respectively
on the PSI (Picture Signal Improvement) board, IV001.
In IV001, Signal Y2H passes through the following stages:
• Alignment stage,
• EDGE REPLACEMENT circuit that improves the signal edges without
creating overshoots.
• CORING and PEAKING circuit that improves signal transitions without
increasing noise.
• BLACK STRETCH circuit that increases contrast in a picture with only a few
small dark areas.
After this processing, the luminance signal is available on Output 9 of IV001,
and is sent to Pin 5 of Connector BV011.
Colour difference signals U2H and V2H are injected at 30 and 28 of IV001, and
pass through the COLOR TRANSIENT IMPROVEMENT circuit before
becoming available on Outputs 1 and 3 of IV001, and sent to Outputs 7 and 6
of Connector BV011.
NOTES :
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