Hi, i am searching for a smart solution for this problem: A cancer ct picture is stored inside a unsigned short array (1-dimensional). I have the location information of the cancer region inside the picture, but the coordinates (x,y) are in superpixel (128x128 unsigned short). My task is to highlight this region. I already solved this one by converting superpixel coordinates into a offset a can use for the unsigned short array. It works fine but i wonder if there is a smarter way to solve this problem, since my solution needs 3 nested for-loops. Is it possible to access the ushort array "superpixelwise", so i can navigate the ushort array in superpixels. ... // i know this does no work ... just to give you an idea what i was thinking of ... typedef struct { unsigned short[128x128] } spix; spix *spixptr; unsigned short * bufptr = img->getBuf(); spixptr = bufptr; ... best regards, zhengtonic