| 摘要 |
<p>PURPOSE:To restore occurrence of a data error immediately and automatically by inserting an image frame subject to compression coding in an in-frame coded mode to a video signal sent to a receiver side for each prescribed number of frames. CONSTITUTION:After a video signal is converted into a digital signal by an A/D converter 1, data are rearranged by a format converter 2 and the resulting data are compression-coded by an image compressor 3. A timer 4 counts number of received frames and provides an output of a refresh signal for each prescribed frame number. Upon the receipt of the refresh signal, the compressor 3 is switched to the in-frame coding mode for the transmission of one frame and a new frame is sent. An audio signal is converted into a digital signal by an A/D converter 5, the converted signal is compression-coded by a voice compressor 6 and its timing is adjusted by a delay device 7 in matching with the video signal. The audio signal and the video signal are multiplexed by a multiplexer 8 and the result is fed through a signal line to a coder 9, in which the signal is subject to error correction coding processing, and the resulting signal is sent to a transmission line.</p> |
