I used imshow on an image to set up a threshold where the pixels fell below a certain number of counts. And, to see if a new point belongs to one of the sparse regions, I set the (y, x) value to a pixel location (row, column) and then see if the pixel is true or false there at that location.
I would like to convert this pixel data back into the original (y,x) coordinates and put them in a text file so I can associate a position in the image (which is essentially a graph) where the regions are sparse and fall below this threshold.
