Merge pull request #41 from norcalli/master

Added Sobel filter

opencv/cv.go

@@ -79,6 +79,17 @@ func Canny(image, edges *IplImage, threshold1, threshold2 float64, aperture_size
 //CVAPI(void)  cvCanny( const CvArr* image, CvArr* edges, double threshold1,
 //                      double threshold2, int  aperture_size CV_DEFAULT(3) );
 
+/* Calculates the first, second, third, or mixed image derivatives using an
+* extended Sobel operator.  */
+func Sobel(src, dst *IplImage, xorder, yorder, aperture_size int) {
+	C.cvSobel(unsafe.Pointer(src), unsafe.Pointer(dst),
+		C.int(xorder), C.int(yorder),
+		C.int(aperture_size),
+	)
+}
+
+// C: void cvSobel(const CvArr* src, CvArr* dst, int xorder, int yorder, int aperture_size=3 )
+
 const (
 	CV_INPAINT_NS    = C.CV_INPAINT_NS
 	CV_INPAINT_TELEA = C.CV_INPAINT_TELEA