Select an image to work with. Extract a small region from it, say 8x8 using
the operator
Extract
and expand it by a factor of 20 using the operator
Expand.
Building the line-grid image.
Use the
Piecewise Linear
operator to create the line-grid image. Look at the
Trapezoidal Data
lesson to find out the proper parameter to generate this image.
Create another similar image, but with horizontal lines and make and
union (maximum) of both using the operator
Maximum.
The image created will have zero as background and the lines with values 255.
To invert the image, use the operator
Subtract From with parameter 255.
Combining the images.
Use the operator
Minimum
applied to the zoomed and the line-grid image.
Exercises
Experiment by changing the pixel values for the line-grid image and
by modifying the magnification factor.