build: avoid highgui dependency

modules/calib3d/CMakeLists.txt

 set(the_description "Camera Calibration and 3D Reconstruction")
-ocv_define_module(calib3d opencv_imgproc opencv_features2d WRAP java python)
+set(debug_modules "")
+if(DEBUG_opencv_calib3d)
+  list(APPEND debug_modules opencv_highgui)
+endif()
+ocv_define_module(calib3d opencv_imgproc opencv_features2d ${debug_modules} WRAP java python)

modules/calib3d/src/calibinit.cpp

@@ -76,6 +76,7 @@
 
 //#define ENABLE_TRIM_COL_ROW
 
+// Requires CMake flag: DEBUG_opencv_calib3d=ON
 //#define DEBUG_CHESSBOARD
 #define DEBUG_CHESSBOARD_TIMEOUT 0  // 0 - wait for 'q'
 

modules/calib3d/src/circlesgrid.cpp

@@ -43,6 +43,8 @@
 #include "precomp.hpp"
 #include "circlesgrid.hpp"
 #include <limits>
+
+ // Requires CMake flag: DEBUG_opencv_calib3d=ON
 //#define DEBUG_CIRCLES
 
 #ifdef DEBUG_CIRCLES

modules/features2d/CMakeLists.txt

 set(the_description "2D Features Framework")
-ocv_define_module(features2d opencv_imgproc OPTIONAL opencv_flann opencv_highgui WRAP java python js)
+set(debug_modules "")
+if(DEBUG_opencv_features2d)
+  list(APPEND debug_modules opencv_highgui)
+endif()
+ocv_define_module(features2d opencv_imgproc ${debug_modules} OPTIONAL opencv_flann WRAP java python js)

modules/features2d/src/blobdetector.cpp

@@ -44,15 +44,11 @@
 #include <iterator>
 #include <limits>
 
+// Requires CMake flag: DEBUG_opencv_features2d=ON
 //#define DEBUG_BLOB_DETECTOR
 
 #ifdef DEBUG_BLOB_DETECTOR
-#  include "opencv2/opencv_modules.hpp"
-#  ifdef HAVE_OPENCV_HIGHGUI
-#    include "opencv2/highgui.hpp"
-#  else
-#    undef DEBUG_BLOB_DETECTOR
-#  endif
+#include "opencv2/highgui.hpp"
 #endif
 
 namespace cv
@@ -200,13 +196,13 @@ void SimpleBlobDetectorImpl::findBlobs(InputArray _image, InputArray _binaryImag
     findContours(binaryImage, contours, RETR_LIST, CHAIN_APPROX_NONE);
 
 #ifdef DEBUG_BLOB_DETECTOR
-    //  Mat keypointsImage;
-    //  cvtColor( binaryImage, keypointsImage, CV_GRAY2RGB );
-    //
-    //  Mat contoursImage;
-    //  cvtColor( binaryImage, contoursImage, CV_GRAY2RGB );
-    //  drawContours( contoursImage, contours, -1, Scalar(0,255,0) );
-    //  imshow("contours", contoursImage );
+    Mat keypointsImage;
+    cvtColor(binaryImage, keypointsImage, COLOR_GRAY2RGB);
+
+    Mat contoursImage;
+    cvtColor(binaryImage, contoursImage, COLOR_GRAY2RGB);
+    drawContours( contoursImage, contours, -1, Scalar(0,255,0) );
+    imshow("contours", contoursImage );
 #endif
 
     for (size_t contourIdx = 0; contourIdx < contours.size(); contourIdx++)
@@ -296,12 +292,12 @@ void SimpleBlobDetectorImpl::findBlobs(InputArray _image, InputArray _binaryImag
 
 
 #ifdef DEBUG_BLOB_DETECTOR
-        //    circle( keypointsImage, center.location, 1, Scalar(0,0,255), 1 );
+        circle( keypointsImage, center.location, 1, Scalar(0,0,255), 1 );
 #endif
     }
 #ifdef DEBUG_BLOB_DETECTOR
-    //  imshow("bk", keypointsImage );
-    //  waitKey();
+    imshow("bk", keypointsImage );
+    waitKey();
 #endif
 }