[Tig] automatic adjustment of TV receiver

[Gary Brasher]

Remember the old

VIR signal for composite TV.  This is basically what you are looking

for. The idea was that at the point the image was color corrected a

signal was put in the vertical interval. Then, even if the tape was

dubbed or run through a proc or otherwise mangled, this signal would

likewise be mangled. The TV set read this signal and used it to put

things back the way they were supposed to be. I thing it was a GE

invention.VIR Vertical Interval Reference signalColor

television receiving apparatus for receiving and demodulating a

composite color television signal including hrozintal synchronizing

signals, color burst signals, and luminance and chrominance components.

This composite color television signal is of the type which

additionally may or may not include a VIR signal which, typically, is

broadcasted in a predetermined line interval during the vertical

retrace period of the composite color video signal. The apparatus

includes the demodulator for demodulating the chrominance component,

which has been separated from the composite video signal, into its

color signal components. A signal generator generates a signal, such as

a gate signal, during the predetermined line interval in which the VIR

signal is expected. Control circuitry is energized by this generated

signal to respond to selected components produced by the demodulator

during the line interval in which the VIR signal is provided for

producing signals which are used to control the color signal components

demodulated by the demodulator, such as to control the hue and

saturation of such demodulated components. Manually operable adjusting

circuitry is coupled to the control circuitry for selectively varying

the control signals in accordance with an operator's particular

preference for hue and/or saturation characteristics of the reproduced

color video picture. In one embodiment, switching circuitry is provided

to selectively energize the control circuitry either with the

aforementioned generated gate signal or, in the event that the

transmitted video signal is not provided with a VIR signal, with an

alternative periodic gating signal, such as a signal derived from the

horizontal sync signal.

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