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 * FileName : random_gen.c
 * Author   : xiahouzuoxin @163.com
 * Version  : v1.0
 * Date     : Tue 29 Jul 2014 08:31:41 PM CST
 * Brief    : 
 * 
 * Copyright (C) MICL,USTB
 */
#include <highgui.h>
#include <iostream>
using namespace std;
using namespace cv;
const char wndname[] = "Drawing";
const int RAND_N = 100;
void (void)
{
    cout<<"Usage:./drawing"<<endl;
}
static Scalar random_color(RNG& rng)
{
    int icolor = (unsigned)rng;
    return Scalar(icolor&0xFF, (icolor>>8)&0xFF, (icolor>>16)&0xFF);
}
int main(int argc, char *argv[])
{
    int line_type = CV_AA;
    int i = 0;
    int width = 1000;
    int height = 700;
    int x1 = -width/2;
    int x2 = width*3/2;
    int y1 = -height/2;
    int y2 = height*3/2;
    const int DELAY = 10;
    RNG rng(0xFFFFFFFF);
    Mat image = Mat::zeros(height, width, CV_8UC3);
    imshow(wndname, image);
    waitKey(DELAY);
    
    for (i=0; i<RAND_N; i++) {
        Point pt1;
        Point 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, random_color(rng), rng.uniform(1,5), line_type);
    }
    imshow(wndname, image);
    waitKey(0);
    for (i=0; i<RAND_N; i++) {
    Point org;
    org.x = rng.uniform(x1, x2);
    org.y = rng.uniform(y1, y2);
    putText(image, "OpenCV",org, rng.uniform(0,8),rng.uniform(0,10)*0.5+0.1, 
            random_color(rng), rng.uniform(1, 10), line_type);
    }
    imshow(wndname, image);
    waitKey(0);
    return 0;
}

1. RNG��OpenCV�е������������࣬�䶨����core.hpp�У�

   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

   class CV_EXPORTS RNG { public: enum { UNIFORM=0, NORMAL=1 }; RNG(); RNG(uint64 _state); //! updates the state and returns the next 32-bit unsigned integer random number unsigned next(); operator uchar(); operator schar(); operator ushort(); operator short(); operator unsigned(); //! returns a random integer sampled uniformly from [0, N). unsigned operator()(unsigned N); unsigned operator ()(); operator int(); operator float(); operator double(); //! returns uniformly distributed integer random number from [a,b) range int uniform(int a, int b); //! returns uniformly distributed floating-point random number from [a,b) range float uniform(float a, float b); //! returns uniformly distributed double-precision floating-point random number from [a,b) range double uniform(double a, double b); void fill( InputOutputArray mat, int distType, InputArray a, InputArray b ); //! returns Gaussian random variate with mean zero. double gaussian(double sigma); uint64 state; };

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2. Mat������ʼ����

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

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   1 2	//! draws the line segment (pt1, pt2) in the image CV_EXPORTS_W void line(Mat& img, Point pt1, Point pt2, const Scalar& color,int thickness=1, int lineType=8, int shift=0);

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4. putText���Խ��������ӵ�ͼƬ�У�

   1 2 3 4 5

   //! renders text string in the image CV_EXPORTS_W void putText( Mat& img, const string& text, Point org, int fontFace, double fontScale, Scalar color, int thickness=1, int linetype=8, bool bottomLeftOrigin=false );

   ����һ������img����Ҫ�������ֵ�ͼ�񣬵ڶ�����������Ҫ���ӵ����֣���������”OpenCV”��

5. ������ɫ����ɫ����RGB��ͨ����ʾ�ģ��������溯������ɫ���������Ͷ���Scalar���͡�Scalar��OpenCV�����������������䳤������Ϊ4ͨ����Դ������

   1	Scalar(icolor&0xFF, (icolor>>8)&0xFF, (icolor>>16)&0xFF);

   ����������ֵȡ���ֱ���ΪRGB����ͨ������ɫֵ��

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