message: reduce extra adaptiveThreshold()
diff: @@ -2273,10 +2273,8 @@ bool QRDecode::updatePerspective()
  pts.push_back(centerPt);
  Mat H = findHomography(pts, perspective_points);
  - Mat bin_original;
  - adaptiveThreshold(original, bin_original, 255, ADAPTIVE_THRESH_GAUSSIAN_C, THRESH_BINARY, 83, 2);
  Mat temp_intermediate;
  - warpPerspective(bin_original, temp_intermediate, H, temporary_size, INTER_NEAREST);
  + warpPerspective(bin_barcode, temp_intermediate, H, temporary_size, INTER_NEAREST);
  no_border_intermediate = temp_intermediate(Range(1, temp_intermediate.rows), Range(1, temp_intermediate.cols));
  const int border = cvRound(0.1 * test_perspective_size);
  