目标

我们将学习在 OpenCV 中进行绘制操作，我们的目标包括：

• 绘制直线。使用 line() 函数。

绘制直线

Draws a line segment connecting two points.

头文件

#include <opencv2/imgproc.hpp>

原型

C++/Java
void cv::line(InputOutputArray img,
              Point 	       pt1,
              Point 	       pt2,
              const Scalar &   color,
              int              thickness = 1,
              int              lineType = LINE_8,
              int              shift = 0)
Python:
img	= cv.line(	img, pt1, pt2, color[, thickness[, lineType[, shift]]]	)

输入参数

例子

#include <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/highgui.hpp>

#define w 400

using namespace cv;

void MyLine(Mat img, Point start, Point end);

int main( void ){
    char atom_window[] = "Drawing 1: Atom";
    char rook_window[] = "Drawing 2: Rook";

    Mat rook_image = Mat::zeros( w, w, CV_8UC3 );
    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 ) );

    imshow( atom_window, atom_image );

    waitKey( 0 );

    return 0;
}

void MyLine( Mat img, Point start, Point end ) {
  int thickness = 2;
  int lineType = LINE_8;
  line( img,
    start,
    end,
    Scalar( 0, 0, 0 ),
    thickness,
    lineType );
}