| 摘要 |
PURPOSE:To simplify circuit constitution, to decrease the cost and to reduce noise by time-base-compressing so that only one out of two kinds of color difference signals in a narrow band will be transfered in a horizontal blanking period of a luminance signal. CONSTITUTION:An NTSC color video signal entering an input terminal 1 is supplied for a low-pass filter and a band filter 3, and a luminance signal and a carrier chrominance component are separated and filtered. The carrier chrominance component from the band filter 3 is demodulated into an I signal EI and a Q signal EQ by a decoder 4. The former is added to a synthesis circuit 7 through a burst removal circuit 5, and the latter is added to the same synthesis circuit 7 through a 1/5 time base compressing circuit 6. Taking consideration of minimizing quality deterioration of a reproduced picture in case of a color video signal having little line correlation, said circuit 6 time-base-compresses an effective horizontal scanning period of the Q signal EQ and a burst level transfer period to one-fifth, and outputs them so that they will be multified in a horizontal blanking period of a luminance signal and transfered. |
