| 摘要 |
PURPOSE:To realize a high-speed masking process and at the same time to reproduce color pictures of high quality by performing the color correction of each color data at a time through the arithmetic processing which is carried out in response to other color data. CONSTITUTION:Each 8-bit chrominance signal of Y, M and C which underwent the photoelectric conversion by a photodetecting unit, the digitization and conversion into color complementary signals are applied to masking processing circuits 150Y, 150M and 150C in the form of 6-bit signal respectively through the shading compensation and the gamma compensation. First, the circuit 150Y performs an operation equivalent to the 1st equation by the 6-bit Y signal, the M signal serving as the color data for compensation and the lower 4 bits of signal C. The value obtained from this operation is outputted as the video data of Y. In the same way, the circuits 150M and 150C also perform operations equivalent to the 2nd and 3rd equations to obtain the video data on compensated M and C. These compensated video data are applied to a laser modulating unit in the form of binary signals underwent modulation of pulse width after the UCR process (160) and the multi-gradation process. |
