3.opencv之画图1

程序来源：F:\opencv\opencv\samples\cpp\tutorial_code\core\Matrix

程序：

/** * @file Drawing_1.cpp * @brief Simple sample code */#include <opencv2/core/core.hpp>#include <opencv2/highgui/highgui.hpp>#define w 400using namespace cv;/// Function headersvoid MyEllipse( Mat img, double angle );void MyFilledCircle( Mat img, Point center );void MyPolygon( Mat img );void MyLine( Mat img, Point start, Point end );/** * @function main * @brief Main function */int main( int argc, char **argv ){  /// Windows names  char atom_window[] = "Drawing 1: Atom";  char rook_window[] = "Drawing 2: Rook";  /// Create black empty images  Mat atom_image = Mat::zeros( w, w, CV_8UC3 );  Mat rook_image = Mat::zeros( w, w, CV_8UC3 );  /// 1. Draw a simple atom:  /// -----------------------  /// 1.a. Creating ellipses  MyEllipse( atom_image, 90 );  MyEllipse( atom_image, 0 );  MyEllipse( atom_image, 45 );  MyEllipse( atom_image, -45 );  /// 1.b. Creating circles  MyFilledCircle( atom_image, Point( w/2.0, w/2.0) );  /// 2. Draw a rook  /// ------------------  /// 2.a. Create a convex polygon  MyPolygon( rook_image );  /// 2.b. Creating rectangles  rectangle( rook_image,         Point( 0, 7*w/8.0 ),         Point( w, w),         Scalar( 0, 255, 255 ),         -1,         8 );  /// 2.c. Create a few lines  MyLine( rook_image, Point( 0, 15*w/16 ), Point( w, 15*w/16 ) );  MyLine( rook_image, Point( w/4, 7*w/8 ), Point( w/4, w ) );  MyLine( rook_image, Point( w/2, 7*w/8 ), Point( w/2, w ) );  MyLine( rook_image, Point( 3*w/4, 7*w/8 ), Point( 3*w/4, w ) );  /// 3. Display your stuff!  imshow( atom_window, atom_image );  cvMoveWindow( atom_window, 0, 200 );  imshow( rook_window, rook_image );  cvMoveWindow( rook_window, w, 200 );  waitKey( 0 );  return(0);}/// Function Declaration/** * @function MyEllipse * @brief Draw a fixed-size ellipse with different angles */void MyEllipse( Mat img, double angle ){  int thickness = 2;  int lineType = 8;  ellipse( img,       Point( w/2.0, w/2.0 ),       Size( w/4.0, w/16.0 ),       angle,       0,       360,       Scalar( 255, 0, 0 ),       thickness,       lineType );}/** * @function MyFilledCircle * @brief Draw a fixed-size filled circle */void MyFilledCircle( Mat img, Point center ){  int thickness = -1;  int lineType = 8;  circle( img,      center,      w/32.0,      Scalar( 0, 0, 255 ),      thickness,      lineType );}/** * @function MyPolygon * @function Draw a simple concave polygon (rook) */void MyPolygon( Mat img ){  int lineType = 8;  /** Create some points */  Point rook_points[1][20];  rook_points[0][0] = Point( w/4.0, 7*w/8.0 );  rook_points[0][1] = Point( 3*w/4.0, 7*w/8.0 );  rook_points[0][2] = Point( 3*w/4.0, 13*w/16.0 );  rook_points[0][3] = Point( 11*w/16.0, 13*w/16.0 );  rook_points[0][4] = Point( 19*w/32.0, 3*w/8.0 );  rook_points[0][5] = Point( 3*w/4.0, 3*w/8.0 );  rook_points[0][6] = Point( 3*w/4.0, w/8.0 );  rook_points[0][7] = Point( 26*w/40.0, w/8.0 );  rook_points[0][8] = Point( 26*w/40.0, w/4.0 );  rook_points[0][9] = Point( 22*w/40.0, w/4.0 );  rook_points[0][10] = Point( 22*w/40.0, w/8.0 );  rook_points[0][11] = Point( 18*w/40.0, w/8.0 );  rook_points[0][12] = Point( 18*w/40.0, w/4.0 );  rook_points[0][13] = Point( 14*w/40.0, w/4.0 );  rook_points[0][14] = Point( 14*w/40.0, w/8.0 );  rook_points[0][15] = Point( w/4.0, w/8.0 );  rook_points[0][16] = Point( w/4.0, 3*w/8.0 );  rook_points[0][17] = Point( 13*w/32.0, 3*w/8.0 );  rook_points[0][18] = Point( 5*w/16.0, 13*w/16.0 );  rook_points[0][19] = Point( w/4.0, 13*w/16.0) ;  const Point* ppt[1] = { rook_points[0] };  int npt[] = { 20 };  fillPoly( img,        ppt,        npt,            1,        Scalar( 255, 255, 255 ),        lineType );}/** * @function MyLine * @brief Draw a simple line */void MyLine( Mat img, Point start, Point end ){  int thickness = 2;  int lineType = 8;  line( img,    start,    end,    Scalar( 0, 0, 0 ),    thickness,    lineType );}

运行结果：

函数解释：（画图函数参见：http://www.opencv.org.cn/opencvdoc/2.3.2/html/modules/core/doc/drawing_functions.html）

1.椭圆函数：

void ellipse(Mat& img, Point center, Size axes, double angle, double startAngle, double endAngle, const Scalar&color, int thickness=1, int lineType=8, int shift=0)

该函数是用来在指定图片上绘制椭圆弧线的。

　　参数img为需要绘制椭圆的图像；

　　参数center是该椭圆的中心点坐标；

　　参数axes是该椭圆的长半轴和短半轴；

　　参数angle是该椭圆和水平方向上的旋转夹角；

　　参数startAngle表示绘制椭圆弧线相对该椭圆自己的水平轴的起始角度；

　　参数endAngel表示绘制椭圆弧线相对该椭圆自己的水平轴的终止角度；

　　后面的参数比较普通就不介绍了。

　　绘制椭圆曲线的示意图如下所示：

　　

2.画圆函数：

void circle(Mat& img, Point center, int radius, const Scalar& color, int thickness=1, int lineType=8, intshift=0)

       参数img为需要绘制圆的图像；

　　参数center是该圆的中心点坐标；

　　参数radius是该圆的半径；

        ......

此程序的具体解释见：

http://www.opencv.org.cn/opencvdoc/2.3.2/html/doc/tutorials/core/basic_geometric_drawing/basic_geometric_drawing.html

画图的其他函数见：

http://www.opencv.org.cn/opencvdoc/2.3.2/html/modules/core/doc/drawing_functions.html