User`s manual

Color Creation and Enhancement AW00089316000
172 Basler ace GigE
8.4.4 Matrix Color Transformation on
acA750-30gc Cameras
Introduction
The main objective of matrix color transformation is to make corrections to the color information that
will account for the type of lighting used during image acquisition and to compensate for any
imperfections in the sensor’s color generation process.
On this camera model, the pixel values output by the camera’s imaging sensor undergo a several
step process before being transmitted by the camera:
 In the first step, the pixel values from the sensor are converted into a YUV color signal.
 In the second step, a first matrix transforrmation step converts the Y, U, and V components for
very binned pixel to R, G, and B components and another transformation step takes account of
the specific pre-selected light source. The vector consisting of the R, G, or B component for
each pixel in the image is multiplied by a matrix containing a set of correction values. (For
information about binned pixels, see the "Color Creation on the acA750-30gc" section).
 When the pixel values are in the RGB color space, gamma and white balance correction can
be applied using the features described earlier in this chapter, and hue and saturation can be
adjusted using the feature described later in this chapter.
 Finally, the pixel values are converted back to the YUV color space and transmitted from the
camera.
Matrix Color Transformation Parameters
The first camera parameter associated with matrix color transformation is the Color Transformation
Selector parameter. This parameter is used to select the type of transformation that will be
performed. For acA750gc cameras, YUV to RGB is the only setting available.
The second parameter associated with matrix color transformation is the Light Source Selector
parameter. The following settings are available for this parameter:
 Daylight 6500K - This setting will automatically populate the matrix with a pre-selected set of
values that will make appropriate corrections for images captured with daylight lighting that has
a color temperature of about 6500K. When you select this setting, the camera will also adjust
the white balance settings and the color adjustment settings so that they are appropriate for a
daylight light source with a color temperature of about 6500K.
 Custom - The user can set the values in the matrix as desired. When you select this setting,
the camera will also adjust the white balance settings and the color adjustment settings so that
they have neutral values that do not change the appearance of the colors.
In almost all cases, selecting the setting that populates the matrix with pre-selected values will give
you excellent results with regard to correcting the colors for the light source you are using.
The custom setting should only be used by someone who is thoroughly familiar with matrix color
transformations. Instructions for using the custom setting appear in the next section.