Re: entering an equation

Posted by Wayne Rasband on Jan 20, 2009; 1:46pm
URL: http://imagej.273.s1.nabble.com/entering-an-equation-tp3694011p3694012.html

> Dear list members,
>
> I am using the imageJ to produce radiometric images. The images are  
> results
> of division of two probes with different excitation wavelength.
> Since the ration is in correlation to the parameter I interested, I'm
> looking for a tool to replace the ration values with the parameter  
> value by
> entering the equation.

ImageJ 1.42h, due next week, will have a Process>Math>Equation command  
where you can enter an equation, such as

    v2=v1-0.6/(0.5*v1+0.3)

that will be applied to all the pixels in the image. This will be  
equivalent to running the macro:

   for (y=0; y<getHeight; y++) {
     for (x=0; x<getWidth; x++) {
       v1=getPixel(x,y);
       v2=v1-0.6/(0.5*v1+0.3)
       setPixel(x,y,v2)
     }
   }

-wayne