Synchronization and multiplexing of HDTV signals for transmission in broadband ISDN

Abstract

When a high-definition video signal such as HDTV is to be transmitted in a Broadband-ISDN with a hierarchy, it is desirable that the video transmitter/receiver systems as well as the transmission system operate asynchronously, so that both synthesis and editing of the video are easier. It is also important to realize clock synchronization/transmission multiplexing without a deterioration of picture quality. From such a viewpoint, this paper first proposes a video stuffing method, which is a video/transmission clock synchronization method based on the concept of the synchronizer. Then the proposed multiplex video transmission system combines the synchronization detection for the video and the transmission in the receiver, based on the integer relation between the video block and the transmission frame. Lastly, the synchronous digital hierarchy (SDH) (STM 4-frame or STM 1-frame) transmission is investigated (it uses the HDTV encoding equipment); the SDH can transmit the Broadband-ISDN signal with H4 × 4 or H4 rate, and the effectiveness of the proposed system is demonstrated. As a result of the experiment, the three clocks for the transmitter/receiver as well as the transmission system operated asynchronously, and a satisfactory video can be transmitted and reproduced without the video synchronization detection in the receiver, and without a deterioration of picture quality.