opencv 常用数据结构和函数

点的表示

Point point;

point.x = 10;

point.y = 8;

或者

Point point = point(10, 8);

颜色的表示

Scalar(a, b, c)

红色分量为c，绿色分量为b，蓝色分量为a

尺寸的表示

Size(5, 5)

矩形的表示

Rect(x, y, width, height);

左上角的坐标和矩形的宽和高

颜色空间转换

CV_EXPORTS_W void cvtColor( InputArray src, OutputArray dst, int code, int dstCn=0 );

opencv的图片通道存储顺序是BGR，即蓝绿红，而不是RGB

绘制直线

CV_EXPORTS_W void line(CV_IN_OUT Mat& img, Point pt1, Point pt2, const Scalar& color,
                     int thickness=1, int lineType=8, int shift=0);

绘制椭圆

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

绘制矩形

CV_EXPORTS_W void rectangle(CV_IN_OUT Mat& img, Point pt1, Point pt2,
                          const Scalar& color, int thickness=1,
                          int lineType=8, int shift=0);

绘制圆

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

绘制填充多边形

CV_EXPORTS void fillPoly(Mat& img, const Point** pts,
                         const int* npts, int ncontours,
                         const Scalar& color, int lineType=8, int shift=0,
                         Point offset=Point() );

原文地址：https://www.cnblogs.com/hehe2014/p/10447910.html