JPS6455997A - Signal conversion system - Google Patents

Abstract

PURPOSE:To save signal storing memory area and to make an effective use of other memory areas without uselessness, by extracting only such signal parts as corresponding to a valid image on the input side and the output side of an A/D converter means, and storing the signal parts sequentially in a memory. CONSTITUTION:Only the domain corresponding to a valid image of a luminance signal Y is sampled in a first A/D converter 53 by using a first rate (10.7MHz) clock signal f1 from a clock generator 52, and written in the first memory area 55a of a main memory 55. Also, only the domain corresponding to the valid image of a chrominance signal is sampled in a second A/D converter 54 by using a second rate (3.58MHz) clock signal f2 from the clock signal generator 52, and written in the second memory area 55b of the main memory 55. Therefore, the memory area necessary for storing the above signals can be made small in capacity, hence other memory areas can be effectively used without uselessness.