2016-07-15 05:38:00 -0500 commented question remap single point does not give me the correct value So the mappings work on the whole imframe if I remap it. but if i draw a circle in the remaped image using the mapx.at(imframe.rows/2,imframe.cols/2) it does not follow the remapped image 2016-07-15 05:35:30 -0500 commented question remap single point does not give me the correct value This is the code for creating the maps. This is basically a barrell distortion mapping // clean the room mapx.release(); mapy.release(); // allocate the maps mapx.create( imframe.size(), CV_32FC1 ); mapy.create( imframe.size(), CV_32FC1 ); // the image size int w = imframe.cols; int h = imframe.rows; for (int y = 0; y < h; y++) { int ty= y-Cy; for (int x = 0; x < w; x++) { int tx= x-Cx; int rt= tx*tx+ty*ty; mapx.at(y,x) = (float)(tx*(1+kx*rt)+Cx); } } for (int y = 0;y < h; y++) { int ty= y-Cy; for (int x = 0; x < w; x++) { int tx= x-Cx; int rt= tx*tx+ty*ty; mapy.at(y,x) = (float)(ty*(1+ky*rt)+Cy); } }  2016-07-15 05:22:15 -0500 commented question remap single point does not give me the correct value my mistake... the point can be mapx.at(input.rows/2,input.cols/2) and still give me the wrong value 2016-07-15 05:10:05 -0500 asked a question remap single point does not give me the correct value Hello! I am trying to compute the remaped position of a specific point of an image but it does not give me the correct coordinate as I compare it with the remaped image. is this correct? Point2f relocated = Point2f(mapx.at(input.rows,input.cols),mapy.at(input.rows,input.cols));