随机数发生器&绘制文字---opencv2.4.11

摘自opencv官方例程：随机数发生器&绘制文字---opencv2.4.11

(opencv\sources\samples\cpp\drawing.cpp)

#include "opencv2/core/core.hpp"

#include "opencv2/highgui/highgui.hpp"

#include <stdio.h>

using namespace cv;

static void help()

{

    printf("\nThis program demonstrates OpenCV drawing and text output functions.\n"

    "Usage:\n"

    "   ./drawing\n");

}

static Scalar randomColor(RNG& rng)

{

    int icolor = (unsigned)rng;

    return Scalar(icolor&255, (icolor>>8)&255, (icolor>>16)&255);

}

int main()

{

    help();

    char wndname[] = "Drawing Demo";

    const int NUMBER = 100;

    const int DELAY = 5;

    int lineType = CV_AA; // change it to 8 to see non-antialiased graphics

    int i, width = 1000, height = 700;

    int x1 = -width/2, x2 = width*3/2, y1 = -height/2, y2 = height*3/2;

    RNG rng(0xFFFFFFFF);

    Mat image = Mat::zeros(height, width, CV_8UC3);

    imshow(wndname, image);

    waitKey(DELAY);

    for (i = 0; i < NUMBER; i++)

    {

        Point pt1, pt2;

        pt1.x = rng.uniform(x1, x2);

        pt1.y = rng.uniform(y1, y2);

        pt2.x = rng.uniform(x1, x2);

        pt2.y = rng.uniform(y1, y2);

        line( image, pt1, pt2, randomColor(rng), rng.uniform(1,10), lineType );

        imshow(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    for (i = 0; i < NUMBER; i++)

    {

        Point pt1, pt2;

        pt1.x = rng.uniform(x1, x2);

        pt1.y = rng.uniform(y1, y2);

        pt2.x = rng.uniform(x1, x2);

        pt2.y = rng.uniform(y1, y2);

        int thickness = rng.uniform(-3, 10);

        rectangle( image, pt1, pt2, randomColor(rng), MAX(thickness, -1), lineType );

        imshow(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    for (i = 0; i < NUMBER; i++)

    {

        Point center;

        center.x = rng.uniform(x1, x2);

        center.y = rng.uniform(y1, y2);

        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(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    for (i = 0; i< NUMBER; i++)

    {

        Point pt[2][3];

        pt[0][0].x = rng.uniform(x1, x2);

        pt[0][0].y = rng.uniform(y1, y2);

        pt[0][1].x = rng.uniform(x1, x2);

        pt[0][1].y = rng.uniform(y1, y2);

        pt[0][2].x = rng.uniform(x1, x2);

        pt[0][2].y = rng.uniform(y1, y2);

        pt[1][0].x = rng.uniform(x1, x2);

        pt[1][0].y = rng.uniform(y1, y2);

        pt[1][1].x = rng.uniform(x1, x2);

        pt[1][1].y = rng.uniform(y1, y2);

        pt[1][2].x = rng.uniform(x1, x2);

        pt[1][2].y = rng.uniform(y1, y2);

        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(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    for (i = 0; i< NUMBER; i++)

    {

        Point pt[2][3];

        pt[0][0].x = rng.uniform(x1, x2);

        pt[0][0].y = rng.uniform(y1, y2);

        pt[0][1].x = rng.uniform(x1, x2);

        pt[0][1].y = rng.uniform(y1, y2);

        pt[0][2].x = rng.uniform(x1, x2);

        pt[0][2].y = rng.uniform(y1, y2);

        pt[1][0].x = rng.uniform(x1, x2);

        pt[1][0].y = rng.uniform(y1, y2);

        pt[1][1].x = rng.uniform(x1, x2);

        pt[1][1].y = rng.uniform(y1, y2);

        pt[1][2].x = rng.uniform(x1, x2);

        pt[1][2].y = rng.uniform(y1, y2);

        const Point* ppt[2] = {pt[0], pt[1]};

        int npt[] = {3, 3};

        fillPoly(image, ppt, npt, 2, randomColor(rng), lineType);

        imshow(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    for (i = 0; i < NUMBER; i++)

    {

        Point center;

        center.x = rng.uniform(x1, x2);

        center.y = rng.uniform(y1, y2);

        circle(image, center, rng.uniform(0, 300), randomColor(rng),

               rng.uniform(-1, 9), lineType);

        imshow(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    for (i = 1; i < NUMBER; i++)

    {

        Point org;

        org.x = rng.uniform(x1, x2);

        org.y = rng.uniform(y1, y2);

        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(wndname, image);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    Size textsize = getTextSize("OpenCV forever!", FONT_HERSHEY_COMPLEX, 3, 5, 0);

    Point org((width - textsize.width)/2, (height - textsize.height)/2);

    Mat image2;

    for( 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(wndname, image2);

        if(waitKey(DELAY) >= 0)

            return 0;

    }

    waitKey();

    return 0;

}

#ifdef _EiC

main(1,"drawing.c");

#endif