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Figure 2: Reset the timestamp every second
If one wants to eliminate the (unknown) drift of the master camera’s reset pulse one can use instead a precise
1PPS signal (pulse per second) which can be supplied from host PCs if they are equipped with NTP (network time
protocol software) or GPS devices.
Now the synchronization is very accurate, in the range of several dozen µs due to hardware delay variations in the
input line which acts as reset and the accuracy of the local quartz-based timestamp oscillator (∼100ppm).
Now the counter inside the camera counts seconds and the timestamp adds precise micro seconds resulting in a
very reliable timestamp.
An example of the chunk data attached to the image can be seen below. The timestamp is in µs and Counter1
counts the reset pulses, in this case itself generated by the camera via Timer1.
Figure 3: ChunkData
The task of resetting the counter at the beginning of the acquisition can be done by setting the reset property
accordingly. Of course is this all independent whether the camera is acquiring images in triggered or continuous
mode.
MATRIX VISION GmbH
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