| 摘要 |
PURPOSE:To prevent deterioration of vertical resolution by providing a comb- form filter and a Y/C separating circuit comprising BPF, and using Y/C separating circuit with the BPF in a signal area where the deterioration of vertical resolution will be introduced if the Y/C separation circuit is employed. CONSTITUTION:If the vertical correlation of the illuminance signal does not exist, a signal of large amplitude is inputted to a coefficient generating circuit 25, and the weighting signal has a large value. Accordingly, the illuminance signal 6 and the chromaticity signal 7 that are largely weighted by the output of the BPF120 are obtained. Therefore, the Y/C separation is obtained with less deterioration of the vertical resolution. On the contrary, if the illuminance signal is correlated vertically, a signal of small amplitude of approximately zero level is inputted to the circuit 25, hence the weighting signal 22 has a large value. Therefore, the signals 6 and 7 that are largely weighted by the output of the bomb-form filter 110 are obtained. Thus the Y/C separation is achieved with less disturbance by crosscolor/dot, and the horizontal resolution is improved.
|
