Basler Vision Technologies Sprint Series, Руководство пользователя

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Features
124 Basler sprint Mono Cameras
b. You can also start the generation of a set of DSNU values by using a binary write command
(see Section 7.3 on page 196 ) to write a value to the Generate field of the Shading Value
Generate CSR (see page 178 ).
6. The camera must make at least 64 acquisitions to create a set of DSNU shading correction
values. If your camera is set to control exposure with an ExSync signal, you must generate at
least 64 ExSync signal cycles after you signal the camera to begin generating the values. If
you are running the camera in a free run exposure time control mode, you must wait long
enough for the camera to complete at least 64 acquisitions.
a. When the camera is acquiring the lines it needs to create the DSNU shading values, the
line valid and data valid signals will go high and low as you would normally expect.
However, the data in these lines is not useful to you and should be ignored.
7. Once 64 acquisitions have been completed, the camera calculates the DSNU values:
a. The camera uses the data from the 64 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 each line.
c. For each of the other pixels in the line, the camera determines the offset 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 DSNU shading values that contains the calculated offsets.
8. The generated set of DSNU values is automatically saved in the user shading values file in the
camera’s non-volatile memory. Existing values in the file will be overwritten.
9. 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 64 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 64 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 64 times the line period.