18 Piranha 2 User’s Manual
03-032-00493-14 Teledyne DALSA
Test Pattern Pixels and End-of-line Sequence
To facilitate system-level debugging and verification of data path integrity, the camera
can generate a test pattern. The test pattern is a ramp from 0 to 255DN, then starts at 0
again. Use the test pattern to verify the proper timing and connections between the
camera and the frame grabber.
To alleviate post-processing, Piranha 2 offers an end-of-line sequence that provides basic
calculations including "line counter", "line average", "pixels above threshold", "pixels
below threshold", and "derivative line sum". These basic calculations are the center of
most automatic gain control (AGC) algorithms.
To further aid in debugging and cable/ data path integrity, the first six bits of the output
of the end-of-line sequence are "aa", "55", "aa". Refer to the table below.
By ensuring these values consistently toggle
between "aa" and "55", you can verify cabling
(i.e. no stuck bits)
Monitor these values (either above or below
threshold) and adjust camera gain to keep
these values relatively constant. This
provides a basis for automatic gain control
(AGC)
Use these values to focus the camera.
Generally, the greater the sum the greater the
image contrast