本文实例为大家分享了C++ OpenCV绘制几何图形的具体代码，供大家参考，具体内容如下
绘制几何图形
- 直线
- 矩形
- 多边形
- 圆形
- 椭圆
- 文字
API
直线
CV_EXPORTS_W void line(InputOutputArray img, Point pt1, Point pt2, const Scalar& color,
int thickness = 1, int lineType = LINE_8, int shift = 0);
矩形
CV_EXPORTS_W void rectangle(InputOutputArray img, Point pt1, Point pt2,
const Scalar& color, int thickness = 1,
int lineType = LINE_8, int shift = 0);
上方函数通过两点确定矩形的位置和大小，下方函数则是通过矩形对象 Rect 来确定。
CV_EXPORTS_W void rectangle(InputOutputArray img, Rect rec,
const Scalar& color, int thickness = 1,
int lineType = LINE_8, int shift = 0);
多边形
CV_EXPORTS void polylines(InputOutputArray img, const Point* const* pts, const int* npts,
int ncontours, bool isClosed, const Scalar& color,
int thickness = 1, int lineType = LINE_8, int shift = 0 );
CV_EXPORTS_W void polylines(InputOutputArray img, InputArrayOfArrays pts,
bool isClosed, const Scalar& color,
int thickness = 1, int lineType = LINE_8, int shift = 0 );
圆形
CV_EXPORTS_W void circle(InputOutputArray img, Point center, int radius,
const Scalar& color, int thickness = 1,
int lineType = LINE_8, int shift = 0);
椭圆
CV_EXPORTS_W void ellipse(InputOutputArray img, const RotatedRect& box, const Scalar& color,
int thickness = 1, int lineType = LINE_8);
CV_EXPORTS_W void ellipse(InputOutputArray img, Point center, Size axes,
double angle, double startAngle, double endAngle,
const Scalar& color, int thickness = 1,
int lineType = LINE_8, int shift = 0);
文字
CV_EXPORTS_W void putText( InputOutputArray img, const String& text, Point org,
int fontFace, double fontScale, Scalar color,
int thickness = 1, int lineType = LINE_8,
bool bottomLeftOrigin = false );
示例
官方示例一
#include#include #include #define w 400 using namespace cv; void MyEllipse( Mat img, double angle ); void MyFilledCircle( Mat img, Point center ); void MyPolygon( Mat img ); void MyLine( Mat img, Point start, Point end ); int main( void ){ char atom_window[] = "Drawing 1: Atom"; char rook_window[] = "Drawing 2: Rook"; Mat atom_image = Mat::zeros( w, w, CV_8UC3 ); Mat rook_image = Mat::zeros( w, w, CV_8UC3 ); MyEllipse( atom_image, 90 ); MyEllipse( atom_image, 0 ); MyEllipse( atom_image, 45 ); MyEllipse( atom_image, -45 ); MyFilledCircle( atom_image, Point( w/2, w/2) ); MyPolygon( rook_image ); rectangle( rook_image, Point( 0, 7*w/8 ), Point( w, w), Scalar( 0, 255, 255 ), FILLED, LINE_8 ); 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 ); moveWindow( atom_window, 0, 200 ); imshow( rook_window, rook_image ); moveWindow( rook_window, w, 200 ); waitKey( 0 ); return(0); } void MyEllipse( Mat img, double angle ) { int thickness = 2; int lineType = 8; ellipse( img, Point( w/2, w/2 ), Size( w/4, w/16 ), angle, 0, 360, Scalar( 255, 0, 0 ), thickness, lineType ); } void MyFilledCircle( Mat img, Point center ) { circle( img, center, w/32, Scalar( 0, 0, 255 ), FILLED, LINE_8 ); } void MyPolygon( Mat img ) { int lineType = LINE_8; Point rook_points[1][20]; rook_points[0][0] = Point( w/4, 7*w/8 ); rook_points[0][1] = Point( 3*w/4, 7*w/8 ); rook_points[0][2] = Point( 3*w/4, 13*w/16 ); rook_points[0][3] = Point( 11*w/16, 13*w/16 ); rook_points[0][4] = Point( 19*w/32, 3*w/8 ); rook_points[0][5] = Point( 3*w/4, 3*w/8 ); rook_points[0][6] = Point( 3*w/4, w/8 ); rook_points[0][7] = Point( 26*w/40, w/8 ); rook_points[0][8] = Point( 26*w/40, w/4 ); rook_points[0][9] = Point( 22*w/40, w/4 ); rook_points[0][10] = Point( 22*w/40, w/8 ); rook_points[0][11] = Point( 18*w/40, w/8 ); rook_points[0][12] = Point( 18*w/40, w/4 ); rook_points[0][13] = Point( 14*w/40, w/4 ); rook_points[0][14] = Point( 14*w/40, w/8 ); rook_points[0][15] = Point( w/4, w/8 ); rook_points[0][16] = Point( w/4, 3*w/8 ); rook_points[0][17] = Point( 13*w/32, 3*w/8 ); rook_points[0][18] = Point( 5*w/16, 13*w/16 ); rook_points[0][19] = Point( w/4, 13*w/16 ); const Point* ppt[1] = { rook_points[0] }; int npt[] = { 20 }; fillPoly( img, ppt, npt, 1, Scalar( 255, 255, 255 ), lineType ); } 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 ); }
官方示例二
#include#include #include #include #include using namespace cv; const int NUMBER = 100; const int DELAY = 5; const int window_width = 900; const int window_height = 600; int x_1 = -window_width/2; int x_2 = window_width*3/2; int y_1 = -window_width/2; int y_2 = window_width*3/2; static Scalar randomColor( RNG& rng ); int Drawing_Random_Lines( Mat image, char* window_name, RNG rng ); int Drawing_Random_Rectangles( Mat image, char* window_name, RNG rng ); int Drawing_Random_Ellipses( Mat image, char* window_name, RNG rng ); int Drawing_Random_Polylines( Mat image, char* window_name, RNG rng ); int Drawing_Random_Filled_Polygons( Mat image, char* window_name, RNG rng ); int Drawing_Random_Circles( Mat image, char* window_name, RNG rng ); int Displaying_Random_Text( Mat image, char* window_name, RNG rng ); int Displaying_Big_End( Mat image, char* window_name, RNG rng ); int main( void ) { int c; char window_name[] = "Drawing_2 Tutorial"; RNG rng( 0xFFFFFFFF ); Mat image = Mat::zeros( window_height, window_width, CV_8UC3 ); imshow( window_name, image ); waitKey( DELAY ); c = Drawing_Random_Lines(image, window_name, rng); if( c != 0 ) return 0; c = Drawing_Random_Rectangles(image, window_name, rng); if( c != 0 ) return 0; c = Drawing_Random_Ellipses( image, window_name, rng ); if( c != 0 ) return 0; c = Drawing_Random_Polylines( image, window_name, rng ); if( c != 0 ) return 0; c = Drawing_Random_Filled_Polygons( image, window_name, rng ); if( c != 0 ) return 0; c = Drawing_Random_Circles( image, window_name, rng ); if( c != 0 ) return 0; c = Displaying_Random_Text( image, window_name, rng ); if( c != 0 ) return 0; c = Displaying_Big_End( image, window_name, rng ); if( c != 0 ) return 0; waitKey(0); return 0; } static Scalar randomColor( RNG& rng ) { int icolor = (unsigned) rng; return Scalar( icolor&255, (icolor>>8)&255, (icolor>>16)&255 ); } int Drawing_Random_Lines( Mat image, char* window_name, RNG rng ) { Point pt1, pt2; for( int i = 0; i < NUMBER; i++ ) { pt1.x = rng.uniform( x_1, x_2 ); pt1.y = rng.uniform( y_1, y_2 ); pt2.x = rng.uniform( x_1, x_2 ); pt2.y = rng.uniform( y_1, y_2 ); line( image, pt1, pt2, randomColor(rng), rng.uniform(1, 10), 8 ); imshow( window_name, image ); if( waitKey( DELAY ) >= 0 ) { return -1; } } return 0; } int Drawing_Random_Rectangles( Mat image, char* window_name, RNG rng ) { Point pt1, pt2; int lineType = 8; int thickness = rng.uniform( -3, 10 ); for( int i = 0; i < NUMBER; i++ ) { pt1.x = rng.uniform( x_1, x_2 ); pt1.y = rng.uniform( y_1, y_2 ); pt2.x = rng.uniform( x_1, x_2 ); pt2.y = rng.uniform( y_1, y_2 ); rectangle( image, pt1, pt2, randomColor(rng), MAX( thickness, -1 ), lineType ); imshow( window_name, image ); if( waitKey( DELAY ) >= 0 ) { return -1; } } return 0; } int Drawing_Random_Ellipses( Mat image, char* window_name, RNG rng ) { int lineType = 8; for ( int i = 0; i < NUMBER; i++ ) { Point center; center.x = rng.uniform(x_1, x_2); center.y = rng.uniform(y_1, y_2); Size axes; axes.width = rng.uniform(0, 200); axes.height = rng.uniform(0, 200); double angle = rng.uniform(0, 180); ellipse( image, center, axes, angle, angle - 100, angle + 200, randomColor(rng), rng.uniform(-1,9), lineType ); imshow( window_name, image ); if( waitKey(DELAY) >= 0 ) { return -1; } } return 0; } int Drawing_Random_Polylines( Mat image, char* window_name, RNG rng ) { int lineType = 8; for( int i = 0; i< NUMBER; i++ ) { Point pt[2][3]; pt[0][0].x = rng.uniform(x_1, x_2); pt[0][0].y = rng.uniform(y_1, y_2); pt[0][1].x = rng.uniform(x_1, x_2); pt[0][1].y = rng.uniform(y_1, y_2); pt[0][2].x = rng.uniform(x_1, x_2); pt[0][2].y = rng.uniform(y_1, y_2); pt[1][0].x = rng.uniform(x_1, x_2); pt[1][0].y = rng.uniform(y_1, y_2); pt[1][1].x = rng.uniform(x_1, x_2); pt[1][1].y = rng.uniform(y_1, y_2); pt[1][2].x = rng.uniform(x_1, x_2); pt[1][2].y = rng.uniform(y_1, y_2); const Point* ppt[2] = {pt[0], pt[1]}; int npt[] = {3, 3}; polylines(image, ppt, npt, 2, true, randomColor(rng), rng.uniform(1,10), lineType); imshow( window_name, image ); if( waitKey(DELAY) >= 0 ) { return -1; } } return 0; } int Drawing_Random_Filled_Polygons( Mat image, char* window_name, RNG rng ) { int lineType = 8; for ( int i = 0; i < NUMBER; i++ ) { Point pt[2][3]; pt[0][0].x = rng.uniform(x_1, x_2); pt[0][0].y = rng.uniform(y_1, y_2); pt[0][1].x = rng.uniform(x_1, x_2); pt[0][1].y = rng.uniform(y_1, y_2); pt[0][2].x = rng.uniform(x_1, x_2); pt[0][2].y = rng.uniform(y_1, y_2); pt[1][0].x = rng.uniform(x_1, x_2); pt[1][0].y = rng.uniform(y_1, y_2); pt[1][1].x = rng.uniform(x_1, x_2); pt[1][1].y = rng.uniform(y_1, y_2); pt[1][2].x = rng.uniform(x_1, x_2); pt[1][2].y = rng.uniform(y_1, y_2); const Point* ppt[2] = {pt[0], pt[1]}; int npt[] = {3, 3}; fillPoly( image, ppt, npt, 2, randomColor(rng), lineType ); imshow( window_name, image ); if( waitKey(DELAY) >= 0 ) { return -1; } } return 0; } int Drawing_Random_Circles( Mat image, char* window_name, RNG rng ) { int lineType = 8; for (int i = 0; i < NUMBER; i++) { Point center; center.x = rng.uniform(x_1, x_2); center.y = rng.uniform(y_1, y_2); circle( image, center, rng.uniform(0, 300), randomColor(rng), rng.uniform(-1, 9), lineType ); imshow( window_name, image ); if( waitKey(DELAY) >= 0 ) { return -1; } } return 0; } int Displaying_Random_Text( Mat image, char* window_name, RNG rng ) { int lineType = 8; for ( int i = 1; i < NUMBER; i++ ) { Point org; org.x = rng.uniform(x_1, x_2); org.y = rng.uniform(y_1, y_2); putText( image, "Testing text rendering", org, rng.uniform(0,8), rng.uniform(0,100)*0.05+0.1, randomColor(rng), rng.uniform(1, 10), lineType); imshow( window_name, image ); if( waitKey(DELAY) >= 0 ) { return -1; } } return 0; } int Displaying_Big_End( Mat image, char* window_name, RNG ) { Size textsize = getTextSize("OpenCV forever!", FONT_HERSHEY_COMPLEX, 3, 5, 0); Point org((window_width - textsize.width)/2, (window_height - textsize.height)/2); int lineType = 8; Mat image2; for( int i = 0; i < 255; i += 2 ) { image2 = image - Scalar::all(i); putText( image2, "OpenCV forever!", org, FONT_HERSHEY_COMPLEX, 3, Scalar(i, i, 255), 5, lineType ); imshow( window_name, image2 ); if( waitKey(DELAY) >= 0 ) { return -1; } } return 0; }
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。