Photon Focus MV-D1024E-3D01-160, Руководство пользователя

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4 Functionality
User-defined Look-up Table
In the ’User’ mode, the mapping of input to output grey levels can be configured arbitrarily by
the user. There is an example file in the PFRemote folder.
U s e r L U T
y = f ( x )
1 0 b i t
8 b i t
Figure 4.20: Data path through LUT
4.3.5 Test Images
Test images are generated in the camera FPGA, independent of the image sensor. They can be
used to check the transmission path from the camera to the frame grabber. Independent from
the configured grey level resolution, every possible grey level appears the same number of
times in a test image. Therefore, the histogram of the received image must be flat.
A test image is a useful tool to find data transmission errors that are caused most
often by a defective cable between camera and frame grabber.
Test images give the correct result at full resolution only.
Ramp
Depending on the configured grey level resolution, the ramp test image outputs a constant
pattern with increasing grey level from the left to the right side (see Fig. 4.21).
Figure 4.21: Ramp test images: 8 bit output (left), 10 bit output (middle), 12 bit output (right)
LFSR
The LFSR (linear feedback shift register) test image outputs a constant pattern with a
pseudo-random grey level sequence containing every possible grey level that is repeated for
every row. In 12 bit mode only a fourth of all possible grey values appear.
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