To solve the problem that wiring inside an LSI becomes very complicated when many functions are incorporated in one LSI, clocks, a source oscillation clock ECK and a master clock MCK mutually interfere inside a DSP in a line lock mode and as a result, beat noise is generated in a video signal.

Different frequencies are set as each frequency of the source oscillation clock ECK and the master clock MCK at the time of line lock mode. In this example, the source oscillation clock is set, for example, to 27MHz, the master clock MCK is set, for example, to 28MHz, respectively and difference of frequencies is given to both clocks ECK, MCK.