Video-signal transmitting and receiving apparatus and method for transmitting and receiving high-resolution and low-resolution television signals

摘要

A system capable of performing compatible transmitting and receiving processes, regardless of whether a TV signal on the transmission side is a high-resolution signal or a low-resolution signal or whether the reception side includes a high-resolution display unit or a low- resolution display unit. On the transmission side, a frequency division circuit divides a high-resolution TV signal into signals in a plurality of frequency bands. The signals in each frequency band are converted into signals of a horizontal and vertical low band (a low- resolution TV signal band). The converted signals are coded by coding units, which transmit the coded signals. On the reception side, the coded signals multiplexed on the transmission side are separated and decoded at decoding units. A frequency synthesizing circuit restores the frequency bands of the decoded signals to the original bands. Then, the resulting signals are displayed with a high resolution. A low-resolution signal is coded and then transmitted. The coded signal is decoded on the reception side. The decoded signal is interpolated at an interpolation circuit. The interpolated signal is then displayed on a high-resolution display unit.