| 摘要 |
<p>PURPOSE:To attain the synchronization to an external synchronizing signal without use of a frame synchronizer by providing an address generating means modifying a readout address of a memory based on a phase difference signal from a phase detection means detecting a phase difference between a decoding picture signal and the external synchronizing signal. CONSTITUTION:A filter 3 including a frame memory able to store nearly one pattern, a phase difference detector 4 and a transmission line L are provided to the system for the decoder. Then the phase difference detector 4 detects a phase difference between ain internal control signal and an external synchronizing signal. That is, the detector detects it how many phases in terms of sampling picture element number a frame synchronizing signal based on the internal control signal is deviated from the external synchronizing signal. Then the result of detection is used for modifying the readout address of the frame memory used for the filter 3. Thus, the memory able to store one picture pattern is provided and the filter 3 able to eliminate noise is used and the phase difference between the internal control signal and the external synchronizing signal is detected and the decoding signal is synchronized with the external synchronizing signal. Thus, the economical decoder is obtained without need of a frame synchronizer.</p> |
