Hey guys,

So I'm working through Shiffman's book and I'm working through Chapter 15 about Images. I've built from hand a virtual copy of example 15-13 with just a few, purely cosmetic changes.

Please direct your attention to the following code:
Code:

float[][] matrix = { { -1, -1, -1 } , 
			   { -1, 9, -1 } ,
			   { -1, -1, -1 } } ;
 

Shiffman asserts that if you change these values all to the average of the parts ( all values changed to 1/9 ) then you'll get a blur effect, but this doesn't seem to be the case. When I make such a change, all I get is a black box. Other changes seem to do either nothing or make a light/screen effect.

How do I achieve a blur effect? Is there something I'm not getting?

davbol wrote on Dec 17^th, 2008, 1:30am:



Aha! Science praise you. That trick worked. The book doesn't put down 'f' next to each number in the example. I now have a working model that switches back and forth between sharp/blur on a mouse click.

Quick Question: Is that a casting issue

Edit: Correction, I don't have a working model that changes from blur/sharp on a mouse click! What is the deal After the entire series of code, I added a new function that should change the convolution function's chief input:

(appended to the very bottom of the code)
Code:

void mousePressed() { //This sharpens.
  
  float [][] matrix = { { -1, -1, -1},
			     { -1,  9, -1},
			     { -1,  -1, -1} };
}
 

The program itself works but clicking the mouse doesn't do anything when it should change into Sharpen mode. What gives?