func ProcessImage(img *opencv.IplImage, win *opencv.Window, pos int) error { w := img.Width() h := img.Height() // Create the output image cedge := opencv.CreateImage(w, h, opencv.IPL_DEPTH_8U, 3) defer cedge.Release() // Convert to grayscale gray := opencv.CreateImage(w, h, opencv.IPL_DEPTH_8U, 1) edge := opencv.CreateImage(w, h, opencv.IPL_DEPTH_8U, 1) defer gray.Release() defer edge.Release() opencv.CvtColor(img, gray, opencv.CV_BGR2GRAY) opencv.Smooth(gray, edge, opencv.CV_BLUR, 3, 3, 0, 0) opencv.Not(gray, edge) // Run the edge detector on grayscale opencv.Canny(gray, edge, float64(pos), float64(pos*3), 3) opencv.Zero(cedge) // copy edge points opencv.Copy(img, cedge, edge) win.ShowImage(cedge) return nil }