【opencv450-samples】绘制图形和文本drawing.cpp

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

using namespace cv;

static void help(char** argv)
{
    printf("\nThis program demonstrates OpenCV drawing and text output functions.\n"
        "Usage:\n"
        "   %s\n", argv[0]);
}
//随机颜色
static Scalar randomColor(RNG& rng)
{
    int icolor = (unsigned)rng;
    return Scalar(icolor & 255, (icolor >> 8) & 255, (icolor >> 16) & 255);
}

int main(int /* argc */, char** argv)
{
    help(argv);
    char wndname[] = "Drawing Demo";
    const int NUMBER = 100;
    const int DELAY = 5;
    int lineType = LINE_AA; //将其更改为 LINE_8 以查看非抗锯齿图形 change it to LINE_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);//黑色背景
    waitKey(DELAY);

    for (i = 0; i < NUMBER * 2; 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 arrowed = rng.uniform(0, 6);//是否带箭头

        if (arrowed < 3)
            line(image, pt1, pt2, randomColor(rng), rng.uniform(1, 10), lineType);//随机颜色，随机线宽 直线
        else
            arrowedLine(image, pt1, pt2, randomColor(rng), rng.uniform(1, 10), lineType);//随机颜色 随机线宽 带箭头直线

        imshow(wndname, image);//更新显示
        if (waitKey(DELAY) >= 0)//按键按下
            return 0;//终止程序
    }

    for (i = 0; i < NUMBER * 2; 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);//线宽
        int marker = rng.uniform(0, 10);//标记类型
        int marker_size = rng.uniform(30, 80);//标记轴的长度 [默认 = 20 像素]

        if (marker > 5)
            rectangle(image, pt1, pt2, randomColor(rng), MAX(thickness, -1), lineType);//随机颜色 矩形
        else
            drawMarker(image, pt1, randomColor(rng), marker, marker_size);//在图像中的给定位置绘制一个标记

        imshow(wndname, image);
        if (waitKey(DELAY) >= 0)
            return 0;
    }

    for (i = 0; i < NUMBER; i++)
    {
        Point center;//椭圆中心点坐标
        center.x = rng.uniform(x1, x2);
        center.y = rng.uniform(y1, y2);
        Size axes;
        axes.width = rng.uniform(0, 200);//长轴
        axes.height = rng.uniform(0, 200);//短轴
        double angle = rng.uniform(0, 180);//角度
        //绘制椭圆  
        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] };//轮廓数组
        int npt[] = { 3, 3 };//轮廓点数 数组
        //多边形
        polylines(image, ppt, npt, 2, true, randomColor(rng), rng.uniform(1, 10), lineType);//三角形

        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 };
        //填充多边形
        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);
        //圆
        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);
        //绘制文本
        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);//前景逐渐变暗消失
        putText(image2, "OpenCV forever!", org, FONT_HERSHEY_COMPLEX, 3,
            Scalar(i, i, 255), 5, lineType);//显示文本

        imshow(wndname, image2);
        if (waitKey(DELAY) >= 0)
            return 0;
    }

    waitKey();
    return 0;
}