Drawing Function of Keypoints and Matches

drawMatches

Draws the found matches of keypoints from two images.

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:

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.