Update lsd.cpp

modules/imgproc/src/lsd.cpp

@@ -1146,23 +1146,10 @@ void LineSegmentDetectorImpl::drawSegments(InputOutputArray _image, InputArray l
 
     CV_Assert(!_image.empty() && (_image.channels() == 1 || _image.channels() == 3));
 
-    Mat gray;
     if (_image.channels() == 1)
     {
-        gray = _image.getMatRef();
+        cvtColor(_image, _image, COLOR_GRAY2BGR);
     }
-    else if (_image.channels() == 3)
-    {
-        cvtColor(_image, gray, CV_BGR2GRAY);
-    }
-
-    // Create a 3 channel image in order to draw colored lines
-    std::vector<Mat> planes;
-    planes.push_back(gray);
-    planes.push_back(gray);
-    planes.push_back(gray);
-
-    merge(planes, _image);
 
     Mat _lines;
     _lines = lines.getMat();
@@ -1174,7 +1161,7 @@ void LineSegmentDetectorImpl::drawSegments(InputOutputArray _image, InputArray l
         const Vec4f& v = _lines.at<Vec4f>(i);
         Point2f b(v[0], v[1]);
         Point2f e(v[2], v[3]);
-        line(_image.getMatRef(), b, e, Scalar(0, 0, 255), 1);
+        line(_image, b, e, Scalar(0, 0, 255), 1);
     }
 }