The Grass Valley Group, Inc.

Paul M Trethewey

Daniel J Chaplin

Christopher R Hansen

R Barry Angell

A method for accumulating component video signals non-additively adds the luminance components to produce an accumulated luminance component, and additively adds the chrominance components to produce an accumulated chrominance component. The accumulated chrominance component may be clipped to limit chrominance values in an overlap area to legal color values. The intentional overlap of the component video signals produces an accumulation special effect in the overlap area.

Component video accumulation effect

An apparatus for smoothing an abrupt change in signal level generates a control signal having a curvilinear ramp shape. An amplifier has a step input signal applied to a non-inverting input, a delayed slope control signal applied to a bias terminal, and the output of the amplifier fed back to an inverting input. An RC series circuit is connected between the output of the amplifier and a reference potential, with the control signal taken from the node between the resistor and capacitor. The amplifier is saturated by the step input signal, and is subsequently turned on by the delayed slope control signal so that the amplifier acts initially as a current source for the RC circuit until the slope control signal reaches its full value. Then the RC circuit charges linearly until the intercept voltage of the step input is approached, at which point the amplifier comes out of saturation and acts as a voltage source to exponentially charge the capacitor to the intercept voltage.

Apparatus for smoothing an abrupt change in signal level

A device for providing a visual indication of the value of a variable of an electrical signal has a plurality, n, of driver circuits each having an input terminal for receiving the electrical signal and a plurality, m, of output terminals. Each driver circuit is operable in a mode in which it provides an output signal at its ith output terminal when the value of the variable lies in a range corresponding to the ith increment on a scale of m increments. The position of the scale of m increments associated with each circuit is adjustable so that the scale of m increment associated with the jth driver circuit overlaps by ((m-1)+(n-1)/n) increments the scale of m increments associated with at least one of the (j-1)th circuit and the (j+1)th circuit. Light emitting elements, arranged in an interdigitated grand linear array, are coupled to respective output terminals of the driver circuits.

Growing community of inventors

Penn Valley, CA, United States of America

Paul M Trethewey