Drawing Function of Keypoints and Matches ========================================= drawMatches --------------- Draws the found matches of keypoints from two images. .. ocv:function:: void drawMatches( const Mat& img1, const vector& keypoints1, const Mat& img2, const vector& keypoints2, const vector& matches1to2, Mat& outImg, const Scalar& matchColor=Scalar::all(-1), const Scalar& singlePointColor=Scalar::all(-1), const vector& matchesMask=vector(), int flags=DrawMatchesFlags::DEFAULT ) .. ocv:function:: void drawMatches( const Mat& img1, const vector& keypoints1, const Mat& img2, const vector& keypoints2, const vector >& matches1to2, Mat& outImg, const Scalar& matchColor=Scalar::all(-1), const Scalar& singlePointColor=Scalar::all(-1), const vector >& matchesMask=vector >(), int flags=DrawMatchesFlags::DEFAULT ) :param img1: First source image. :param keypoints1: Keypoints from the first source image. :param img2: Second source image. :param keypoints2: Keypoints from the second source image. :param matches1to2: Matches from the first image to the second one, which means that ``keypoints1[i]`` has a corresponding point in ``keypoints2[matches[i]]`` . :param outImg: Output image. Its content depends on the ``flags`` value defining what is drawn in the output image. See possible ``flags`` bit values below. :param matchColor: Color of matches (lines and connected keypoints). If ``matchColor==Scalar::all(-1)`` , the color is generated randomly. :param singlePointColor: Color of single keypoints (circles), which means that keypoints do not have the matches. If ``singlePointColor==Scalar::all(-1)`` , the color is generated randomly. :param matchesMask: Mask determining which matches are drawn. If the mask is empty, all matches are drawn. :param flags: Flags setting drawing features. Possible ``flags`` bit values are defined by ``DrawMatchesFlags``. This function draws matches of keypoints from two images in the output image. Match is a line connecting two keypoints (circles). The structure ``DrawMatchesFlags`` is defined as follows: .. code-block:: cpp struct DrawMatchesFlags { enum { DEFAULT = 0, // Output image matrix will be created (Mat::create), // i.e. existing memory of output image may be reused. // Two source images, matches, and single keypoints // will be drawn. // For each keypoint, only the center point will be // drawn (without a circle around the keypoint with the // keypoint size and orientation). DRAW_OVER_OUTIMG = 1, // Output image matrix will not be // created (using Mat::create). Matches will be drawn // on existing content of output image. NOT_DRAW_SINGLE_POINTS = 2, // Single keypoints will not be drawn. DRAW_RICH_KEYPOINTS = 4 // For each keypoint, the circle around // keypoint with keypoint size and orientation will // be drawn. }; }; .. drawKeypoints ----------------- Draws keypoints. .. ocv:function:: void drawKeypoints( const Mat& image, const vector& keypoints, Mat& outImage, const Scalar& color=Scalar::all(-1), int flags=DrawMatchesFlags::DEFAULT ) :param image: Source image. :param keypoints: Keypoints from the source image. :param outImage: Output image. Its content depends on the ``flags`` value defining what is drawn in the output image. See possible ``flags`` bit values below. :param color: Color of keypoints. :param flags: Flags setting drawing features. Possible ``flags`` bit values are defined by ``DrawMatchesFlags``. See details above in :ocv:func:`drawMatches` .