SAMPLING PHASE ADJUSTMENT DEVICE IN PICTURE PROCESSING SYSTEM

摘要

PURPOSE:To obtain higher picture quality by realizing the phase adjustment device making a sampling timing of a video camera section coincident with a phase of an A/D conversion timing of a picture processing section automatically. CONSTITUTION:A test signal of a test signal generating circuit 33 is A/D- converted by an A/D converter circuit 28 after the test mode is set and the result is analyzed by a system control circuit 39 to obtain a phase error of timing clocks between a video camera section 21 and a picture processing section 22 and a phase adjustment circuit 27a of a synchronizing coupling circuit 27 adjusts the phase of the clock of a timing clock generating circuit 25 based on the error information. The phases of both the timing clocks are made coincident through the repetition of the sequence thereby eliminating deterioration in picture due to a phase difference of the sampling time in the normal mode and the timing of the A/D conversion.