#include #include#include#include#include#include#include#include#include

using namespacecv;using namespacestd;//單通道圖片直方圖繪制

void drawHist(vectornums)

{

Mat hist= Mat::zeros(600, 800, CV_8UC3);

auto Max= max_element(nums.begin(), nums.end());//max迭代器類型,最大數目

putText(hist, "Histogram", Point(150, 100), FONT_HERSHEY_DUPLEX, 1, Scalar(255, 255, 255));//*********繪制坐標系************// Point o = Point(100, 550);

Point x= Point(700, 550);

Point y= Point(100, 150);//x軸

line(hist, o, x, Scalar(255, 255, 255), 2, 8, 0);//y軸

line(hist, o, y, Scalar(255, 255, 255), 2, 8, 0);//********繪制灰度曲線***********// Point pts[256];//生成坐標點

for (int i = 0; i < 256; i++)

{

pts[i].x= i * 2 + 100;

pts[i].y= 550 - int(nums[i]*(300.0/(*Max)));//歸一化到[0, 300]//顯示橫坐標

if ((i + 1) % 16 == 0)

{string num = format("%d", i + 1);

putText(hist, num, Point(pts[i].x,570), FONT_HERSHEY_SIMPLEX, 0.5, Scalar(255, 255, 255));

}

}//繪制線

for (int i = 1; i < 256; i++)

{

line(hist, pts[i- 1], pts[i], Scalar(0, 255, 0), 2);

}//顯示圖像

imshow("直方圖",hist);

}//三通道圖片直方圖繪制

void drawHist(vector &r, vector &g, vector &b)

{

Mat hist= Mat::zeros(600, 800, CV_8UC3);

putText(hist,"Histogram", Point(150, 100), FONT_HERSHEY_DUPLEX, 1, Scalar(255, 255, 255));//*********繪制坐標系************// Point o = Point(100, 550);

Point x= Point(700, 550);

Point y= Point(100, 150);//x軸

line(hist, o, x, Scalar(255, 255, 255), 2, 8, 0);//y軸

line(hist, o, y, Scalar(255, 255, 255), 2, 8, 0);//********繪制灰度曲線***********// auto Max_r =max_element(r.begin(), r.end());

auto Max_g=max_element(g.begin(), g.end());

auto Max_b=max_element(b.begin(), b.end());

Point pts[3][256];//生成坐標點

for (int i = 0; i < 256; i++)

{

pts[0][i].x = i * 2 + 100;

pts[0][i].y = 550 - int(r[i] * (300.0 / (*Max_r)));//歸一化到[0, 300]

pts[1][i].x = i * 2 + 100;

pts[1][i].y = 550 - int(g[i] * (300.0 / (*Max_g)));//歸一化到[0, 300]

pts[2][i].x = i * 2 + 100;

pts[2][i].y = 550 - int(b[i] * (300.0 / (*Max_b)));//歸一化到[0, 300]//顯示橫坐標

if ((i + 1) % 16 == 0)

{string num = format("%d", i + 1);

putText(hist, num, Point(pts[0][i].x, 570), FONT_HERSHEY_SIMPLEX, 0.5, Scalar(255, 255, 255));

}

}//繪制線

for (int i = 1; i < 256; i++)

{

line(hist, pts[0][i - 1], pts[0][i], Scalar(255, 0, 0), 2);

line(hist, pts[1][i - 1], pts[1][i], Scalar(0, 255, 0), 2);

line(hist, pts[2][i - 1], pts[2][i], Scalar(0, 0, 255), 2);

}//顯示圖像

imshow("直方圖", hist);

}//灰度直方圖計算

void calHist(const stringimg)

{

Mat src, grey;//讀取圖象

src =imread(img);if (!src.data)

{

cout<< "Image：" + img + "讀取失敗" <

}//先轉為灰度圖

cvtColor(src, grey, COLOR_BGR2GRAY);

imshow("灰度圖", grey);//計算各灰度級像素個數

vector nums(256);for (int i = 0; i < grey.rows; i++)

{

uchar* p = grey.ptr(i);for (int j = 0; j < grey.cols; j++)

{

nums[p[j]]++;

}

}

drawHist(nums);

}//多通道直方圖計算

void calHist(const string img, intpattern)

{

Mat src, grey;//讀取圖象

src =imread(img);if (!src.data)

{

cout<< "Image：" + img + "讀取失敗" <

}

imshow("原圖像",src);//計算各灰度級像素個數

vector r(256, 0);

vector g(256, 0);

vector b(256, 0);for (int i = 0; i < src.rows; i++)

{

uchar* p = src.ptr(i);for (int j = 0; j < src.cols; j++)

{

r[p[j* 3 + 0]]++;

g[p[j* 3 + 1]]++;

b[p[j* 3 + 2]]++;

}

}

drawHist(r, g, b);

}intmain()

{string img = "D:\\trashBox\\testIMG\\tiger.jpg";

calHist(img);//計算灰度直方圖

calHist(img, 0);//計算三色直方圖

waitKey(0);return 0;

}

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