Basler Vision Technologies Sprint Series, Руководство пользователя

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Features
Basler sprint Mono Cameras 127
However, the data in these lines is not useful to you and should be ignored.
9. Once 128 acquisitions have been completed, the camera calculates the PRNU values:
a. The camera uses the data from the 128 acquisitions to calculate an average gray value for
the pixels in each line.
b. The camera finds the pixel with the highest average gray value in the line.
c. For each of the other pixels in the line, the camera determines the additional gain that
would be needed to make the pixel’s average value equal to the average value for the
highest pixel.
d. The camera generates a set of PRNU values that contains the calculated gain adjustments.
10. The generated set of PRNU values is automatically stored in the user shading values file in the
camera’s non-volatile memory. Existing values in the file will be overwritten.
11. The user shading value file is automatically "activated." See Section 6.3.3 on page 128 for
more information about what it means to activate a shading file.
Note
If you started the generation of the shading values using the CCT+, you are
using an ExSync signal to trigger acquisitions, and you are operating the
camera at a line period greater than approximately 300 ms, you should be
aware of a potential problem. Under these conditions, the CCT+ may time out
while it is waiting for the camera to complete 128 acquisitions and you may
see a “Camera is not responding ...” error message. This error is not fatal to
the shading value creation process. If you close the error message window,
wait several seconds and then click the Refresh button on the CCT+, the
shading values will be properly created.
If you started the generation of the shading values using binary commands,
you are using an ExSync signal to trigger acquisitions, and you are operating
the camera at very low line rates, you should be aware of a restriction. The
camera will not acknowledge or respond to binary commands while it is
performing the 128 acquisitions needed to create a set of shading values.
Once you have issued the binary command to start generating shading
values, you should wait until the generation process is complete before you
issue any further binary commands. The time needed to complete the
generation process will be equal to 128 times the line period.