Merge pull request #5390 from StevenPuttemans:add_markers_2.4

modules/core/include/opencv2/core/core.hpp

@@ -2639,6 +2639,44 @@ CV_EXPORTS_W void ellipse(CV_IN_OUT Mat& img, Point center, Size axes,
 CV_EXPORTS_W void ellipse(CV_IN_OUT Mat& img, const RotatedRect& box, const Scalar& color,
                         int thickness=1, int lineType=8);
 
+/* ----------------------------------------------------------------------------------------- */
+/* ADDING A SET OF PREDEFINED MARKERS WHICH COULD BE USED TO HIGHLIGHT POSITIONS IN AN IMAGE */
+/* ----------------------------------------------------------------------------------------- */
+
+//! Possible set of marker types used for the drawMarker function
+enum MarkerTypes
+{
+    MARKER_CROSS = 0,           // A crosshair marker shape
+    MARKER_TILTED_CROSS = 1,    // A 45 degree tilted crosshair marker shape
+    MARKER_STAR = 2,            // A star marker shape, combination of cross and tilted cross
+    MARKER_DIAMOND = 3,         // A diamond marker shape
+    MARKER_SQUARE = 4,          // A square marker shape
+    MARKER_TRIANGLE_UP = 5,     // An upwards pointing triangle marker shape
+    MARKER_TRIANGLE_DOWN = 6    // A downwards pointing triangle marker shape
+};
+
+/** @brief Draws a marker on a predefined position in an image.
+
+The function drawMarker draws a marker on a given position in the image. For the moment several
+marker types are supported (`MARKER_CROSS`, `MARKER_TILTED_CROSS`, `MARKER_STAR`, `MARKER_DIAMOND`, `MARKER_SQUARE`,
+`MARKER_TRIANGLE_UP` and `MARKER_TRIANGLE_DOWN`).
+
+@param img Image.
+@param position The point where the crosshair is positioned.
+@param markerType The specific type of marker you want to use, see
+@param color Line color.
+@param thickness Line thickness.
+@param line_type Type of the line, see cv::LineTypes
+@param markerSize The length of the marker axis [default = 20 pixels]
+ */
+CV_EXPORTS_W void drawMarker(CV_IN_OUT Mat& img, Point position, const Scalar& color,
+                             int markerType = MARKER_CROSS, int markerSize=20, int thickness=1,
+                             int line_type=8);
+
+/* ----------------------------------------------------------------------------------------- */
+/* END OF MARKER SECTION */
+/* ----------------------------------------------------------------------------------------- */
+
 //! draws a filled convex polygon in the image
 CV_EXPORTS void fillConvexPoly(Mat& img, const Point* pts, int npts,
                                const Scalar& color, int lineType=8,

modules/core/src/drawing.cpp

@@ -1797,6 +1797,73 @@ void ellipse(Mat& img, const RotatedRect& box, const Scalar& color,
     EllipseEx( img, center, axes, _angle, 0, 360, buf, thickness, lineType );
 }
 
+/* ----------------------------------------------------------------------------------------- */
+/* ADDING A SET OF PREDEFINED MARKERS WHICH COULD BE USED TO HIGHLIGHT POSITIONS IN AN IMAGE */
+/* ----------------------------------------------------------------------------------------- */
+
+void drawMarker(Mat& img, Point position, const Scalar& color, int markerType, int markerSize, int thickness, int line_type)
+{
+    switch(markerType)
+    {
+    // The cross marker case
+    case MARKER_CROSS:
+        line(img, Point(position.x-(markerSize/2), position.y), Point(position.x+(markerSize/2), position.y), color, thickness, line_type);
+        line(img, Point(position.x, position.y-(markerSize/2)), Point(position.x, position.y+(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // The tilted cross marker case
+    case MARKER_TILTED_CROSS:
+        line(img, Point(position.x-(markerSize/2), position.y-(markerSize/2)), Point(position.x+(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y-(markerSize/2)), Point(position.x-(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // The star marker case
+    case MARKER_STAR:
+        line(img, Point(position.x-(markerSize/2), position.y), Point(position.x+(markerSize/2), position.y), color, thickness, line_type);
+        line(img, Point(position.x, position.y-(markerSize/2)), Point(position.x, position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x-(markerSize/2), position.y-(markerSize/2)), Point(position.x+(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y-(markerSize/2)), Point(position.x-(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // The diamond marker case
+    case MARKER_DIAMOND:
+        line(img, Point(position.x, position.y-(markerSize/2)), Point(position.x+(markerSize/2), position.y), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y), Point(position.x, position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x, position.y+(markerSize/2)), Point(position.x-(markerSize/2), position.y), color, thickness, line_type);
+        line(img, Point(position.x-(markerSize/2), position.y), Point(position.x, position.y-(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // The square marker case
+    case MARKER_SQUARE:
+        line(img, Point(position.x-(markerSize/2), position.y-(markerSize/2)), Point(position.x+(markerSize/2), position.y-(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y-(markerSize/2)), Point(position.x+(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y+(markerSize/2)), Point(position.x-(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x-(markerSize/2), position.y+(markerSize/2)), Point(position.x-(markerSize/2), position.y-(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // The triangle up marker case
+    case MARKER_TRIANGLE_UP:
+        line(img, Point(position.x-(markerSize/2), position.y+(markerSize/2)), Point(position.x+(markerSize/2), position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y+(markerSize/2)), Point(position.x, position.y-(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x, position.y-(markerSize/2)), Point(position.x-(markerSize/2), position.y-(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // The triangle down marker case
+    case MARKER_TRIANGLE_DOWN:
+        line(img, Point(position.x-(markerSize/2), position.y-(markerSize/2)), Point(position.x+(markerSize/2), position.y-(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x+(markerSize/2), position.y-(markerSize/2)), Point(position.x, position.y+(markerSize/2)), color, thickness, line_type);
+        line(img, Point(position.x, position.y+(markerSize/2)), Point(position.x-(markerSize/2), position.y-(markerSize/2)), color, thickness, line_type);
+        break;
+
+    // If any number that doesn't exist is entered, draw a cross marker
+    default:
+        drawMarker(img, position, color, MARKER_CROSS, markerSize, thickness, line_type);
+        break;
+    }
+}
+
+/* ----------------------------------------------------------------------------------------- */
+
 void fillConvexPoly( Mat& img, const Point* pts, int npts,
                      const Scalar& color, int line_type, int shift )
 {