Sharpness; Gamma And Lookup Table - FLIR GRASSHOPPER 3 Series Technical Reference

Auto Exposure ROI—Allows the user to specify a region of interest within the full image to be used for both auto
exposure and white balance. The ROI position and size are relative to the transmitted image. If the request ROI is
of zero width or height, the entire image is used. Auto Exposure ROI is not supported on quad tap sensor cameras.
To control auto exposure:
GenICam—Acquisition Control
n
FlyCapture
n

8.12 Sharpness

The Grasshopper3 PGE supports sharpness adjustment, which refers to the filtering of an image to reduce blurring
at image edges. Sharpness is implemented as an average upon a 3x3 block of pixels, and is only applied to the
green component of the Bayer tiled pattern. For sharpness values greater than 1024, the pixel is sharpened; for
values less than 1024 it is blurred. When sharpness is in auto mode and gain is low, then a small amount of
sharpening is applied, which increases as gain decreases. If gain is high, a small amount of blur is applied,
increasing as gain increases.
When the camera is outputting raw Bayer data, Sharpness is disabled by default. Otherwise, the default setting is
enabled.
To adjust sharpness use:
GenICam—Analog Control
n
FlyCapture
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8.13 Gamma and Lookup Table

The camera supports gamma and lookup table (LUT) functionality. In a GenICam application, gamma and LUT are
available when the Image Format Control has On Board Color Processing enabled.
Sensor manufacturers strive to make the transfer characteristics of sensors inherently linear, which means that as
the number of photons hitting the imaging sensor increases, the resulting image intensity increases are linear.
Gamma can be used to apply a non-linear mapping of the images produced by the camera. Gamma is applied
after analog-to-digital conversion and is available in all pixel formats except Raw. Gamma values between 0.5 and
1 result in decreased brightness effect, while values between 1 and 4 produce an increased brightness effect. By
default, Gamma is enabled and has a value of 1.25. To obtain a linear response, disable gamma.
For 8-bit, gamma is applied as:
OUT = 255*(IN/255)^1/gamma
Lookup Table allows the user to access and control a lookup table (LUT), with entries stored on-board the camera.
The LUT is modified under the following circumstances:
2/10/2017
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FLIR Integrated Imaging
Solutions Inc. All rights reserved.
API—Setting Auto Exposure Using the FlyCapture API
API—Setting Sharpness Using the FlyCapture API
Note: When Gamma is turned on, Lookup Table is turned off.
When Lookup Table is turned on, Gamma is turned off.
Grasshopper
8 Grasshopper3 PGE Attributes
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3 PGE Technical Reference
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