Relative A/V Delay Testing
In this mode, the relative delay between audio and video is measured. The OmniTek A/V Delay Test Sequence generator may be installed remotely to the video analyzer, which means that it is possible to measure A/V delays in satellite, cable, or terrestrial broadcast links.
Transmission Path |
OmniGen
OmniView
Note that the delay test sequence may be played out from an Gen system, a videotape machine, or a video file server.
In this mode, the View software analyses the input video signal, looking for the first frame in the sequence (identified by the binary code). When this is detected, an internal timer counts the time delay before the audio input pulse is detected. The system automatically detects whether the audio pulse is early or late with respect to the video, and displays the results accordingly.
The delay range that the system is capable of measuring is:
| 50Hz Systems | 60Hz Systems |
Audio early with respect to video: | 0 ~ 5760 ms | 0 ~ 4800 ms |
Video early with respect to audio: | 0 ~ 1920 ms | 0 ~ 1600 ms. |
The relative time delay measurement is always expressed in milliseconds, and the accuracy is better than 1 ms.
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