Patent ID: 7881346

Claim:
An apparatus for transmitting terrestrial digital data that includes image data using a synchronous-optical-network system or a synchronous-digital-hierarchy system, the apparatus comprising: a synchronous-difference calculating unit to receive a synchronous signal used in the synchronous-optical-network system or the synchronous-digital-hierarchy system, receive a first broadcasting transport stream synchronous signal that synchronizes with a starting point in each of the image data included in the terrestrial digital data, calculate a synchronous difference between the synchronous signal and the first broadcasting transport stream synchronous signal, and generate data that notifies an absence of a synchronous difference data if the calculated synchronous difference is not within a cycle of the synchronous signal; and a transmission processing unit to transmit the synchronous difference or the generated data that notifies of an absence of the synchronous difference data together with the terrestrial digital data to a destination.