To successibly transmit moving picture data asynchronously with a transmission clock of a transmission line.

A frame.pulse representing the first time of a frame of a moving picture received from a frame.pulse input section 201 is counted according to a transmission clock generated by a dock generating section 203 and a frame.count is obtained. A data mixer section 205 mixes this frame.count with moving picture data received from a data input section 202 and the result is outputted to a transmission line 206. A bit series received via the transmission line 206 is given to a clock recovery section 207, where the transmission clock is recovered and given to a data separate section 209, in which the bit string is separated into the moving picture data and the frame.count. A clock counter 208 counts the separated frame.count according to the transmission clock to restore the interval of the frame.pulses. The restored frame.pulse is outputted synchronously with the moving picture data.