公开(公告)号：US07020894B1

公开(公告)日：2006-03-28

申请号：US09744374

申请日：1999-07-16

申请人： Russell Mark Godwin ,  John Michael Wilson

发明人： Russell Mark Godwin ,  John Michael Wilson

IPC分类号： H04N7/16 ,  H04N9/475 ,  H04N17/00 ,  H04N17/02

CPC分类号： H04N17/00 ,  H04N5/04 ,  H04N5/60 ,  H04N21/242 ,  H04N21/4307

摘要： In order to synchronise video and audio signals, a video test signal and an audio test signal are generated at the transmitting end of a transmission link, and transmitted over the link. The video test signal has first and second active picture periods of contrasting states. The audio test signal has first and second periods of contrasting states. As generated, the video and audio test signals have a predetermined timing relationship—for example, their changes of respective states may be coincident in time. At the receiving end of the link, the video and audio test signals as received are detected, and any difference of timing between the video and audio test signals is derived from their changes of respective states, measured and displayed, including an indication of whether the video signal arrived before the audio signal or vice-versa. Additionally or alternatively, such a measurement signal can be used in a control loop to compensate for the delay and automatically re-synchronise the audio and video signals. The system is particularly suitable for transmission of video and audio over separate paths of a link—e.g. respectively over satellite and terrestrial paths.

摘要翻译： 为了同步视频和音频信号，在传输链路的发送端生成视频测试信号和音频测试信号，并通过链路发送。 视频测试信号具有对比状态的第一和第二活动图像周期。 音频测试信号具有第一和第二周期的对比状态。 如产生的，视频和音频测试信号具有预定的定时关系，例如，它们各自状态的变化可能在时间上是一致的。 在链路的接收端，检测到接收到的视频和音频测试信号，并且视频和音频测试信号之间的任何时间差异都来源于其测量和显示的各自状态的变化，包括是否 视频信号在音频信号之前到达，反之亦然。 另外或替代地，这样的测量信号可以用在控制环路中以补偿延迟并自动重新同步音频和视频信号。 该系统特别适用于通过链路的单独路径传输视频和音频 - 例如。 分别通过卫星和地面路径。