Bipolar Image Display

Bipolar images are those with both positive and negative values. Actual images can only displayed with a positive range, from 0 to 1 or from 0 to 255, for example. Bipolar images must be transformed in some way to a positive range in order to be displayed.

Convolve3.java uses a Sobel edge operator which generates ouput from -255 to +255, when normalized by dividing by a scale of 8.

Usage of Convolve3 is

java Convolve3  filename  bipolar_style scale mag
where bipolar_style can be 0, 1, or 2. Scale should be 8, but smaller values will enhance the bipolar effect.
The mag argument will enlarge the output display by pixel replication.

Examples

binary image

C:\ece538\class\imsrc5>java Convolve3 char.png 0 4 3

convolution mask

 -1   0   1
 -2   0   2
 -1   0   1

originalbipolar_style = 0bipolar_style = 1

Grayscale image

original image

style=0 scl=8style=0 scl=4style=0 scl=2style=0 scl=1
style=1 scl=4style=1 scl=8style=1 scl=2style=1 scl=1


Maintained by John Loomis, last updated 7 March 2018