+
+// CvMat stub;
+ // CvMat * background = cvGetMat(frame, &stub, 0, 0);
+
+// CvMat *cv8u = cvCreateMat(frame->width, frame->height, CV_8U);
+// double min, max;
+// CvPoint a,b;
+// cvMinMaxLoc(background, &min, &max, &a, &b, 0);
+
+// double ccscale = 255.0/(max-min);
+// double ccshift = -min;
+ //cvCvtScale(frame, cv8u, ccscale, ccshift);