PCM RECORDING SYSTEM FOR PICTURE SIGNAL

• Main Author: KOIKE YUKIO
• Format: Patent
• Language: English
• Published: 13.11.1989
• Subjects: ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; PICTORIAL COMMUNICATION, e.g. TELEVISION

PURPOSE:To avoid unnecessary increase of the hardware and to improve picture quality considerably by varying the A/D conversion characteristic of a color difference signal depending on the level of a luminance signal. CONSTITUTION:The A/D conversion characteristic of a color difference signal is changed depending on the level of the luminance signal. Thus, the conversion circuit 8 varies the converting characteristic of the A/D converters 5, 6 by setting an input level representing the lowest code change point (L level for A/D converters 5, 6) of the A/D converters 5, 6 for the color difference signal depending on the level of the Y signal and an input level (H level for A/D converters 5, 6) representing the highest code change point to a prescribed value. Thus, the accuracy of the A/D converters for the color difference signal is utilized effectively to the utmost so as to avoid the unnecessary increase of the hardware and the picture quality is improved considerably.