For every pixel in a image, we will need to test it against every other pixel. '''This make it makes its complexity of O(n^2)'''. For example a 256x256 has 65536 pixel. Each pixel would have to be tested against 65536 pixels to find out the nearest corresponding pixel. '''So it needs 65536 * 65536 = 4,294,967,296 checksarray element look ups!''' === Why I chose this ===I chose SDF image conversion because it has lots of potential for parallelization. Since all the operations of a pixel are independent of each other and reads data from one single array, this allows for massive gains when using GPU multi-threading.