Point Grey Flea3 GigE Technical Reference
8 Flea3 GigE Attributes
There are four parameters that affect Auto Exposure:
Auto Exposure Range
—Allows the user to specify the range of allowed exposure values to be used by the automatic
exposure controller when in auto mode.
Auto Shutter Range
—Allows the user to specify the range of shutter values to be used by the automatic exposure
controller which is generally some subset of the entire shutter range.
Auto Gain Range
—Allows the user to specify the range of gain values to be used by the automatic exposure controller
which is generally some subset of the entire gain range.
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.
To control auto exposure:
n
GenICam—
Acquisition Control
n
FlyCapture API—
Setting Auto Exposure Using the FlyCapture API
8.12 Sharpness
The Flea3 GigE 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 1000, the pixel is sharpened; for values less than 1000 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:
n
GenICam—
Analog Control
n
FlyCapture API—
Setting Sharpness Using the FlyCapture API
8.13 Gamma and Lookup Table
The camera supports gamma and lookup table (LUT) functionality.
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. 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
Revised 10/29/2013
Copyright ©2010-2013 Point Grey Research Inc.
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