Changing Image Pixels Continuously

Hi all,

I’m new to OF and programming in general. I’m trying to create an application that displays an image of a map. Then, using a range slider from ofxDatGui, I’m trying to alter certain pixels like in examples/graphics/simpleColorKey - except mine needs to continuously change as the slider is moved. I’m just using ofImage right now, and it works overall, but the program responds very slow. Any idea on how to speed up the response time? I’m sure I need to use something other than ofImage, just can’t seem to find what to use. Thanks in advance!!