diff --git a/modules/structured_light/CMakeLists.txt b/modules/structured_light/CMakeLists.txt
index 494d58c8b..66bcc2756 100644
--- a/modules/structured_light/CMakeLists.txt
+++ b/modules/structured_light/CMakeLists.txt
@@ -1,2 +1,2 @@
 set(the_description "Structured Light API")
-ocv_define_module(structured_light opencv_core opencv_calib3d opencv_imgproc opencv_highgui opencv_features2d opencv_viz opencv_rgbd)
\ No newline at end of file
+ocv_define_module(structured_light opencv_core opencv_calib3d opencv_imgproc opencv_highgui opencv_features2d opencv_rgbd OPTIONAL opencv_viz)
diff --git a/modules/structured_light/samples/pointcloud.cpp b/modules/structured_light/samples/pointcloud.cpp
index f006dcb0f..97419dcc1 100644
--- a/modules/structured_light/samples/pointcloud.cpp
+++ b/modules/structured_light/samples/pointcloud.cpp
@@ -45,7 +45,12 @@
 #include <opencv2/calib3d.hpp>
 #include <opencv2/imgproc.hpp>
 #include <opencv2/structured_light.hpp>
+#include <opencv2/opencv_modules.hpp>
+
+// (if you did not build the opencv_viz module, you will only see the disparity images)
+#ifdef HAVE_OPENCV_VIZ
 #include <opencv2/viz.hpp>
+#endif
 
 using namespace std;
 using namespace cv;
@@ -73,13 +78,13 @@ static bool readStringList( const string& filename, vector<string>& l )
   if( !fs.isOpened() )
   {
     cerr << "failed to open " << filename << endl;
-    return -1;
+    return false;
   }
   FileNode n = fs.getFirstTopLevelNode();
   if( n.type() != FileNode::SEQ )
   {
     cerr << "cam 1 images are not a sequence! FAIL" << endl;
-    return -1;
+    return false;
   }
 
   FileNodeIterator it = n.begin(), it_end = n.end();
@@ -92,7 +97,7 @@ static bool readStringList( const string& filename, vector<string>& l )
   if( n.type() != FileNode::SEQ )
   {
     cerr << "cam 2 images are not a sequence! FAIL" << endl;
-    return -1;
+    return false;
   }
 
   it = n.begin(), it_end = n.end();
@@ -104,7 +109,7 @@ static bool readStringList( const string& filename, vector<string>& l )
   if( l.size() % 2 != 0 )
   {
     cout << "Error: the image list contains odd (non-even) number of elements\n";
-    return -1;
+    return false;
   }
   return true;
 }
@@ -133,8 +138,8 @@ int main( int argc, char** argv )
   if( argc == 7 )
   {
     // If passed, setting the white and black threshold, otherwise using default values
-    white_thresh = parser.get<size_t>( 4 );
-    black_thresh = parser.get<size_t>( 5 );
+    white_thresh = parser.get<unsigned>( 4 );
+    black_thresh = parser.get<unsigned>( 5 );
 
     graycode->setWhiteThreshold( white_thresh );
     graycode->setBlackThreshold( black_thresh );
@@ -271,6 +276,7 @@ int main( int argc, char** argv )
     resize( thresholded_disp, dst, Size( 640, 480 ) );
     imshow( "threshold disp otsu", dst );
 
+#ifdef HAVE_OPENCV_VIZ
     // Apply the mask to the point cloud
     Mat pointcloud_tresh, color_tresh;
     pointcloud.copyTo( pointcloud_tresh, thresholded_disp );
@@ -283,8 +289,10 @@ int main( int argc, char** argv )
     myWindow.showWidget( "pointcloud", viz::WCloud( pointcloud_tresh, color_tresh ) );
     myWindow.showWidget( "text2d", viz::WText( "Point cloud", Point(20, 20), 20, viz::Color::green() ) );
     myWindow.spin();
+#endif // HAVE_OPENCV_VIZ
+
   }
 
   waitKey();
   return 0;
-}
\ No newline at end of file
+}
diff --git a/modules/structured_light/src/graycodepattern.cpp b/modules/structured_light/src/graycodepattern.cpp
index 0418c8980..d3df7aa2a 100644
--- a/modules/structured_light/src/graycodepattern.cpp
+++ b/modules/structured_light/src/graycodepattern.cpp
@@ -89,11 +89,11 @@ class CV_EXPORTS_W GrayCodePattern_Impl : public GrayCodePattern
 
   // Number between 0-255 that represents the minimum brightness difference
   // between the fully illuminated (white) and the non - illuminated images (black)
-  int blackThreshold;
+  size_t blackThreshold;
 
   // Number between 0-255 that represents the minimum brightness difference
   // between the gray-code pattern and its inverse images
-  int whiteThreshold;
+  size_t whiteThreshold;
 
   // Computes the required number of pattern images, allocating the pattern vector
   void computeNumberOfPatternImages();
@@ -220,8 +220,8 @@ bool GrayCodePattern_Impl::decode( InputArrayOfArrays patternImages, OutputArray
     std::vector<Mat> shadowMasks;
     computeShadowMasks( blackImages, whitheImages, shadowMasks );
 
-    size_t cam_width = acquired_pattern[0][0].cols;
-    size_t cam_height = acquired_pattern[0][0].rows;
+    int cam_width = acquired_pattern[0][0].cols;
+    int cam_height = acquired_pattern[0][0].rows;
 
     Point projPixel;
 
@@ -233,9 +233,9 @@ bool GrayCodePattern_Impl::decode( InputArrayOfArrays patternImages, OutputArray
     for( size_t k = 0; k < acquired_pattern.size(); k++ )
     {
       camsPixels[k].resize( params.height * params.width );
-      for( size_t i = 0; i < cam_width; i++ )
+      for( int i = 0; i < cam_width; i++ )
       {
-        for( size_t j = 0; j < cam_height; j++ )
+        for( int j = 0; j < cam_height; j++ )
         {
           //if the pixel is not shadowed, reconstruct
           if( shadowMasks[k].at<uchar>( j, i ) )
@@ -345,10 +345,10 @@ void GrayCodePattern_Impl::computeShadowMasks( InputArrayOfArrays blackImages, I
     {
       for( int j = 0; j < cam_height; j++ )
       {
-        uchar white = whiteImages_[k].at<uchar>( Point( i, j ) );
-        uchar black = blackImages_[k].at<uchar>( Point( i, j ) );
+        double white = whiteImages_[k].at<uchar>( Point( i, j ) );
+        double black = blackImages_[k].at<uchar>( Point( i, j ) );
 
-        if( white - black > blackThreshold )
+        if( abs(white - black) > blackThreshold )
         {
           shadowMasks_[k].at<uchar>( Point( i, j ) ) = ( uchar ) 1;
         }
@@ -472,4 +472,4 @@ Ptr<GrayCodePattern> GrayCodePattern::create( const GrayCodePattern::Params& par
 }
 
 }
-}
\ No newline at end of file
+}
diff --git a/modules/structured_light/test/test_getProjPixel.cpp b/modules/structured_light/test/test_getProjPixel.cpp
index d90955fbc..91c6db5d9 100644
--- a/modules/structured_light/test/test_getProjPixel.cpp
+++ b/modules/structured_light/test/test_getProjPixel.cpp
@@ -73,12 +73,12 @@ void CV_GetProjPixelTest::run( int )
 
   Point projPixel;
 
-  size_t image_width = pattern[0].cols;
-  size_t image_height = pattern[0].rows;
+  int image_width = pattern[0].cols;
+  int image_height = pattern[0].rows;
 
-  for( size_t i = 0; i < image_width; i++ )
+  for( int i = 0; i < image_width; i++ )
   {
-    for( size_t j = 0; j < image_height; j++ )
+    for( int j = 0; j < image_height; j++ )
     {
       //for a (x,y) pixel of the camera returns the corresponding projector pixel
       bool error = graycode->getProjPixel( pattern, i, j, projPixel );
@@ -97,4 +97,4 @@ TEST( GrayCodePattern, getProjPixel )
 {
   CV_GetProjPixelTest test;
   test.safe_run();
-}
\ No newline at end of file
+}
diff --git a/modules/structured_light/test/test_plane.cpp b/modules/structured_light/test/test_plane.cpp
index 658f24a07..36f5b840c 100644
--- a/modules/structured_light/test/test_plane.cpp
+++ b/modules/structured_light/test/test_plane.cpp
@@ -45,7 +45,6 @@
 #include <opencv2/highgui.hpp>
 #include <opencv2/calib3d.hpp>
 #include <opencv2/imgproc.hpp>
-#include <opencv2/viz.hpp>
 
 using namespace std;
 using namespace cv;
@@ -360,4 +359,4 @@ TEST( GrayCodePattern, plane_reconstruction )
 {
   CV_PlaneTest test;
   test.safe_run();
-}
\ No newline at end of file
+}