C++ OpenCV绘制几何图形

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 <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/highgui.hpp>
#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 <opencv2/core.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/highgui.hpp>
#include <iostream>
#include <stdio.h>
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。