发明公开
- 专利标题: Method and apparatus for reproducing a chrominance signal
- 专利标题(中): 用于再现色彩信号的方法和装置
-
申请号: EP84307529申请日: 1984-11-01
-
公开(公告)号: EP0140716A3公开(公告)日: 1986-06-25
- 发明人: Nakagawa, Yukio , Tomita, Masao , Matsumoto, Tokikazu
- 申请人: Matsushita Electric Industrial Co., Ltd.
- 专利权人: Matsushita Electric Industrial Co., Ltd.
- 当前专利权人: Matsushita Electric Industrial Co., Ltd.
- 优先权: JP20510883 19831101; JP24940483 19831224; JP22872083 19831202; JP23566083 19831213; JP23844983 19831216; JP2222384 19840208
- 主分类号: H04N09/83
- IPC分类号: H04N09/83
摘要:
A low-range-converted carrier chrominance signal (C L ) is demodulated (17) and a base-band signal is passed through a holding circuit and a comb filter (18a, 18b) in converting the low-range-converted carrier chrominance signal into a base-band chrominance signal or a carrier chrominance signal having a prescribed subcarrier frequency, for thereby removing an unwanted side band component and a crosstalk from adjacent tracks, which are produced upon demodulation, so that a low-pass or bandpass filter (21) for removing a side band produced by the conversion may be dispensed with or may have less strict characteristics. Furthermore, the carrier chrominance signal is generated by a means (22, 23, 24) for synchronising the low-range-converted chrominance signal (62) in phase with the low-range conversion carrier, sampling (16) the low-range-converted i chrominance signal with a first clock signal (eF c ) having a frequency which is a multiple of that of the low-range conversion carrier, converting the sampled data into two color difference signal sampled data (e, f) and synthesizing the two color difference signal sampled data (e, f) for issuance with a reference clock signal (4Fsc) which is n times the carrier frequency of the carrier chrominance signal. With this arrangement, the number of circuit components required is reduced and the circuit components can easily be made as a a semiconductor device.
信息查询