Lookup Table (Lut) Overview; Lut Size Vs. Output Pixel Format - Teledyne G3-GM10-M0641 User Manual

Lookup Table (LUT) Overview

The Genie Nano cameras include a user programmable LUT table as a component of its embedded
processing features. A LUT is used for operations such as gamma adjustments, invert and
threshold processes.
The camera LUT table are dependent on the sensor (per pixel – see feature LUT Size) and is
illustrated in the following figure (see Processing path bits per pixel). Pixel data from the sensor is
passed through the LUT memory array, where the new programmed pixel value is then passed to
the Genie output circuit. The LUT data table is stored along with other parameters with the user
configuration function.
Sensor

LUT Size vs. Output Pixel Format

The LUT size will be the same as the camera's sensor pixel size. All camera processing is performed
at the sensor pixel format of the camera, while the user chooses the output pixel format (such as
8-bit).
Using the example of a 10-bit Nano camera, the LUT table is also 10-bit. The Nano default neutral
LUT programming is as follows:
When the Output Pixel format = 10-bit, the default LUT data value is equal to the LUT index
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value for each index. This is a linear LUT that does not modify the sensor data.
When the Output Pixel format = 8-bit, the default LUT data is programmed to map the 1024
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sensor pixel values to 256 output values. Therefore LUT index "0 to 3" have the value "0", LUT
index "4 to 7" have the value "1", and so on until the last group where LUT index "1020 to
1023" have the value "255".
LUT data is selected either as a predefined gamma correction, or is programmed with individual
values for various LUT index entries, or a user LUT data file is upload using the File Access controls.
Refer to the Sapera documentation for information about the SapLut Class. Note that a SapLut file
can be uploaded to the Nano but cannot be read back.
Nano Series GigE Vision Camera
Simplified Nano LUT Block Diagram
(10-bit example)
0 1023
1 1022
Pixel
Data
2 1021
3 1020
1020
1021
1022
1023
Simplified Example 10-bit LUT Block Diagram
Output
LUT Programmed
3
as Invert Function
2
1
0
Operational Reference
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