3-3將圖片加入隨機的雜訊

3-3將圖片加入隨機的雜訊

程式說明:

運行結果:

   底下左圖是增加了高斯雜訊的部分，底下右圖則是增加了椒鹽雜訊的部分

範例程式:

#include <iostream>
#include <opencv2/opencv.hpp>
#include <opencv2/highgui/highgui.hpp>

double normal() // value = -6.0 ~ 6.0
{
   double value = 0;
   for (int i = 0; i != 12; ++i)
   {
     value += ((double)rand() / RAND_MAX); // single from: 0 ~ 1; valueTotal from: 0 ~ 12
   }
   return value - 6.0;
}

void SaltPepperNoiseImage(cv::Mat& Image, float threshold, int imageSize)
{
   float random = 0;
   int value = 0;
   for (int y = 0; y < imageSize; y++)
   {
     for (int x = 0; x < imageSize; x++)
     {
       random = ((float)rand() / RAND_MAX); // from 0 ~ 1
       if (random < threshold)
         value = 0;
       else if (random >(1 - threshold))
         value = 255;
       else
         value = Image.at(y, x);


       Image.at(y, x) = value;
     }
   }
}

void GassianNoiseImage(cv::Mat& Image, float amplitude, int imageSize)
{
   double random = 0;
   int noise = 0;
   int value = 0;
   for (int y = 0; y < imageSize; y++)
   {
     for (int x = 0; x < imageSize; x++)
     {
       random = normal();
       noise = (int)(amplitude*random);
       value = Image.at(y, x) + noise;
       if (value>255)
         Image.at(y, x) = 255;
       else if (value < 0)
         Image.at(y, x) = 0;
       else
         Image.at(y, x) = value;
     }
   }
}

int main(int argc, char** argv)
{
   cv::Mat img = cv::imread("lena.bmp", 0);
   if (img.empty())
   {
     std::cout << "無法讀取圖片" << std::endl;
     return -1;
   }

     cv::Mat imgWithGaussianNoise = img.clone();
     cv::Mat imgWithPepperSaltNoise = img.clone();
     GassianNoiseImage(imgWithGaussianNoise, 30, imgWithGaussianNoise.cols);
     SaltPepperNoiseImage(imgWithPepperSaltNoise, 0.05, imgWithGaussianNoise.cols);

     cv::imshow("ImgWithGaussianNoise", imgWithGaussianNoise);
     cv::waitKey(0);

     cv::imshow("ImgWithPepperSaltNoise", imgWithPepperSaltNoise);
     cv::waitKey(0);

     cv::imwrite("ImgWithGaussianNoise.bmp", imgWithGaussianNoise);
     cv::imwrite("ImgWithPepperSaltNoise.bmp", imgWithPepperSaltNoise);

   return 0;
}