3.6
API Features
Host-assisted image processing features available in xiAPI
3.6.1
Exposure – Auto gain
When AEAG is used, every captured image is evaluated for its mean intensity. Based on the result, the exposure and gain values are
modified with the objective to achieve a target intensity level for the following image. Further, the maximum applicable exposure and gain
values can be defined. Since both, exposure and gain, have an influence on the intensity, the ratio between those two parameters in their
contribution to the algorithm can also be set (exposure priority).
3.6.2
White balance
Only for color models: The white balance can be adjusted with three coefficients kR, kG and kB, one for each color channel. These
coefficients can be set individually in order to increase or decrease each channel’s contribution and therefore allow the user to control the
color tint of the image.
Assisted manual white balance
This feature measures the white balance a single time and sets the white balance coefficient to achieve a mean grey (neutral) tint. The
measurement is performed on the central rectangle of the image, with 1/8th of its width and height. The function expects a white sheet of
paper exposed to 50% of the intensity values (8 Bit RGB values should be around 128) to be visible.
Auto White Balance
The white balance is measured across the full image for every 4th image that is acquired, and the white balance coefficients are set to to
achieve a neutral colour tint.
3.6.3
Gamma
Only for color models: As a part of the color filtering process, it is possible to adjust the gamma level of the image. The adjustment can be
set separately for the luminosity and the chromaticity.
3.6.4
Sharpness
Only for color models: As a part of the color filtering process, it is possible to adjust the sharpness of the image.
3.6.5
Color correction matrix
The color correction matrix is a 4x4-matrix which is applied on each pixel of an image in a host-assisted port-processing step. This Matrix
can be used for example to adjust the brightness, contrast, and saturation.
3.6.6
Sensor defect correction
During the manufacturing process, every camera is tested for various type of defects and a list of the measured defect pixels is created and
stored in the camera’s non-volatile memory. This list is then used for the correction of acquired images during operation. The correction is
inactive by default, but can be turned on by the user if a non-processed output is required.
XIMEA Technical Manual, Version: v230927
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