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OptoFidelity Video Multimeter
– User Manual
Graph scale colors (green, yellow, red) come from different standards and suggestions.
Limits, which are only instructive, are set as follows:
•
Green (Good): within -15 … +45 ms (Acceptance limit according to ATSC IS-
191)
•
Yellow (Moderate): within -45 … +125 ms (Human noticeable limit according
to ITU-R BT.1359-1)
•
Red (Poor): over -45 … +125 ms (Human noticeable limit according to ITU-R
BT.1359-1)
It is important to understand that, for example, a moderate result does not necessarily
indicate that the measured video is perceived as bad. This is because the final user
experience also depends on the video content and watching context (large TV set
versus small mobile terminal). The above-mentioned standards and suggestions are
useful references when product/service–specific acceptance limits are defined.
4.4
Saved data files with Lip sync option
When the
Lip sync
feature is activated an additional column of results appears in the
results data file. The column is named ‘Lip sync (ms)’. The measured lip sync value is
printed at each detected ‘k’ frame (black color marker).
Figure 14: Data file saved from frame rate measurement, including lip sync
5
USB connection
Video Multimeter can be connected to a computer by a USB cable for battery charging
and data transfer. Charging will begin as soon as the USB cable is connected and is
indicated by a red LED next to the USB connector. When the battery is full, the LED
will turn off. Note that if the device is on, the LED will not turn off because power is
being used.
