Signal processing system for video camera

Abstract

Abstract PURPOSE:To obtain proper white balance to a color temperature over a wide range from indoor color temperature to outdoor color temperature by detecting color temperature and varying a matrix constant of a color demodulation matrix in response to the detected color temperature. CONSTITUTION:An automatic white balance circuit 9 generates a DC control signal CD controlling the gain of a red and blue AGC circuit in a process circuit 8 so that a level ratio of color difference signals (R-YL), (B-YL) from a circuit such as the process circuit 8 is a prescribed value, that is, the white balance is taken. The DC control signal CD is fed to a matrix correction circuit 11, from which a control signal CM controlling a color demodulation matrix circuit 3 is formed so as to have a prescribed matrix constant in response to the color temperature. Thus, excellent white balance is obtained over a wide range of color temperature by having only to add a circuit with simple constitution to obtain excellent color reproducibility even at the image pickup at indoor or outdoor.

Inventors

• 👤 Seiji Tanaka
• 👤 誠二 田中

Bibliographic Details