User Guide

Chapter 10: Visualization And Analysis
3. In the Filter operation mode dialog box, select the options you want to use.
4. Click OK.
Expression
The Math Expression filter can be used to perform mathematical equations on a color channel.
To use the Math Expression filter:
1. Select the color channel from the Target menu. The available color channels depend on the
image mode; i.e., CMYK, RGB, etc.
2. Define the mathematical equation using the Categories scroll box and their related items.
3. Double-click on an item to make it appear in the Expression field.
The lower portion of the dialog box indicates the correct syntax and shows an example
of the expression.
4. Click Apply to see the effect. Clicking Revert stops the effect on the color channel.
5. Click OK to permanently apply the effect to the channel.
To apply the Math Expression filter to multiple images:
1. Select the images.
2. Apply the filter by choosing Image | Filter | Scientific | Expression.
3. In the Filter operation mode dialog box, select the options you want to use.
4. Click OK.
Convolve
The Convolve filter can be used to apply a spatial convolution on an image or selected image area. The
convolution is performed according to a kernel, which is basically a matrix whose size you define in
terms of width and height in pixels. Note that only odd numbers can be used to define the size of the
kernel. The maximum is 11 pixels and the minimum, 3 pixels.
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