Alkeria NECTA Series - High Resolution Line Period; Line Delay

8. Capturing Images 96
Note
When the minimum line period is recomputed due to parameter changes (e.g.
the packet size), the current line period is automatically reset to the minimum
line period. See Section 8.9.7 for further details.
In general, the minimum value for the line period is determined by four factors:
• the time required for the conversion and transfer of the line from the sensor to the camera;
• the exposure time (that prevails over the line period)
1
;
• the bandwidth available on the USB bus;
• the size of the selected ROI.
To achieve the largest frame rate allowed by the application (see also Section 8.9.8):
• decrease the ADC resolution (decreasing the conversion time for each frame);
• ensure that the shutter time does not increase the minimum acquisition period;
• set the optimal packet size, i.e. the maximum allowed given current operating conditions;
• use the lowest ROI size compatibile with the application.
Example Code 8.9 | Set LinePeriod property
// Set 80 us, without exceeding the minimum allowed value.
device.LinePeriod = Math.Max(device.MinLinePeriod, 80.0);
8.7.1 High resolution Line period
This read-only property gives the actual value of line period that is congured into the sensor. When the
exposure time approach to expected line period (or become longer), line period needs to be incremented
by the given amount of time the sensor requires to perform the acquisition
1
.
Example Code 8.10 | Retireve High Resolution line period
float actualLinePeriod = device.HighResLinePeriod;
8.8 LINE DELAY
The line delay control is available in all double-line (both color and monochrome) cameras.
1
Actual line period is always larger than the current exposure time, plus a 2.1 µs overhead