Clock control method and system

The invention discloses a clock control method which is used for controlling clock synchronization between a transmitting end and a receiving end, and the transmitting end and the receiving end are connected through an audio and video transmission channel. The method comprises the following steps: acquiring a crystal oscillator frequency of the receiving end and a cache parameter of an audio and video signal; calculating a crystal oscillator error between the transmitting end and the receiving end according to the change rate of the cache parameter of the receiving end; generating a correctioncoefficient according to the calculated crystal oscillator error; correcting the crystal oscillator frequency of the receiving end according to the generated correction coefficient to obtain a correction frequency; generating a clock signal of the receiving end according to the obtained correction frequency. According to the clock control method, clock synchronization between the transmitting endand the receiving end can