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4 Functionality
4.9 Convolver
4.9.1 Functionality
The "Convolver" is a discrete 2D-convolution filter with a 3x3 convolution kernel. The kernel
coefficients can be user-defined.
The M x N discrete 2D-convolution p
(x,y) of pixel p
(x,y) with convolution kernel h, scale s
out
in
and offset o is defined in Fig. 4.46.
Figure 4.46: Convolution formula
4.9.2 Settings
The following settings for the parameters are available:
Offset Offset value o (see Fig. 4.46). Range: -4096 ... 4095
Scale Scaling divisor s (see Fig. 4.46). Range: 1 ... 4095
Coefficients Coefficients of convolution kernel h (see Fig. 4.46). Range: -4096 ... 4095.
Assignment to coefficient properties is shown in Fig. 4.47.
Figure 4.47: Convolution coefficients assignment
4.9.3 Examples
Fig. 4.48 shows the result of the application of various standard convolver settings to the
original image. shows the corresponding settings for every filter.
A filter called Unsharp Mask is often used to enhance near infrared images. Fig. 4.50 shows
examples with the corresponding settings.
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