Frequency improving circuit for chrominance signal

Abstract

Abstract PURPOSE: To prevent the color blotting of the demodulated chrominance signal by varying the delay amount of the carrier chrominance signal by the correction signal formed based on the high band component of the luminance signal to increase the range of the carrier chrominance signal. CONSTITUTION: Carrier chrominance signal Sc is supplied to color demodulator circuit 2 to change the low-band luminance signal to YN and the narrow-band signals of red, green and blue to RN, GN and BN respectively. In this case, color difference signal RN-YN, GN-YN and BN-YN respectively are demodulated and then supplied to matrix circuit 3 to form primary color signals R, G and B. At the same time, the correction signal corresponding to the contour part of the picture formed based on high-band component YH of the luminance signal is applied to variable delay circuit 10, and the delay amount is varied to increase the range of the carrier chrominance signal. Thus, the color blotting can be prevented for the demodulated chrominance signal. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Takahisa Tsuchiya
• 👤 Takafumi Okada
• 👤 Yoshio Ishigaki
• 👤 Shoji Omori

Bibliographic Details