Method and device for synchronizing coded signals

A coded signal processing device for executing preselected processing with a first and a second coded signal representative of a particular moving picture each and coded by a preselected coding system while synchronizing said first coded signal and said second coded signal, and outputting processed coded signals, said coded signal processing device comprising:

• a first path;
• a second path;
• and
• a coded signal processor;
• said first path and said second path each including:
• a code storage for sequentially storing an input coded signal;
• a decoder for decoding the input coded signal to thereby produce an original moving picture signal;
• an encoder for re-encoding the moving picture signal output from said decoder by the preselected coding system;
• a selector for selectively outputting a coded signal output from said encoder or the coded signal read out of said code storage;
• and
• a signal controller for controlling reading of the coded signal out of said code storage, output of the coded signal from said encoder, and switching of said selector;
• said coded signal processor executing the preselected processing with the coded signal selected by said selector of said first path and said selector of said second path to thereby process the moving picture, and outputting said coded signal in a form of a coded signal.
• wherein the first coded signal is input to said code storage and said decoder of said first path while the second coded signal is input to said code storage and said decoder of said second path, said signal controller of said first path and said signal controller of said second path respectively feeding, based on a reference synchronizing signal which is a common reference for frame synchronizing signals of moving picture signals, said first coded signal and said second coded signal to said coded signal processor while synchronizing said first coded signal and said second coded signal frame by frame.

A coded signal processing device for executing preselected processing with a first coded signal and a second coded signal representative of a moving picture each and coded by a preselected coding system while synchronizing said first coded signal and said second coded signal to each other, and outputting processed coded signals, said coded signal processing device comprising:

• a first code storage for sequentially storing the first coded signal;
• a first decoder for decoding the first coded signal to thereby produce an original moving picture signal;
• an encoder for re-encoding the moving picture signal output from said first decoder by the preselected coding system;
• a selector for selectively outputting a coded signal output from said encoder or the coded signal read out of said first code storage;
• a signal controller for controlling reading of the coded signal out of said first code storage, output of the coded signal from said encoder, and switching of said selector;
• a second code storage for sequentially storing the second coded signal;
• a second decoder for decoding the second coded signal to thereby produce an original moving picture signal;
• and
• a coded signal processor for executing the preselected processing with the coded signal output from said selector and the coded signal output from said second code storage to thereby process the moving picture, and then outputting said first coded signal and second coded signal in a form of coded signals.

A method of processing a coded signal representative of a moving picture coded by a preselected coding system while synchronizing said coded signals, said method comprising the steps of:

• (a) decoding the coded signal to thereby detect a synchronizing signal picture by picture;
• (b) comparing the synchronizing signal with a preselected reference synchronizing signal to thereby detect a phase difference;
• (c) temporarily storing the coded signal and reading out said coded signal in accordance with the reference synchronizing signal;
• (d) re-encoding one by one moving picture signals produced by decoding the coded signal;
• (e) selecting and then processing either one of the coded signal read out in step (c) and a coded signal output by step (d);
• (f) repeatedly reading out, when the phase difference detected in step (b) is smaller than a first preselected value, an intra-coded frame two times for synchronization in step (c);
• and
• (g) omitting, when the phase difference detected in step (b) is greater than a second preselected value, any one of inter-coded frames of the moving picture signal decoded in step (d) and appearing between two consecutive intra-coded frames, while re-encoding the moving picture signal of the other frames to thereby synchronize the coded signal to the reference synchronizing signal.