Precision horizontal positioning system

摘要

A precision horizontal positioning (PHP) system for precisely positioning two overlaid video images includes a phase-locked loop, a frame controller, and a delay circuit. The precision horizontal positioning system adjusts the phase of a second video signal until the start of active video of the second video signal coincides with the start of active video of a first video signal. The delay circuit is incorporated in the feedback path of the horizontal synchronization signal of the second video signal such that the second video signal is pushed forward in time to align horizontally with the first video signal.