11. 对一幅灰度图像增加高频噪声，再对其进行频域低通滤波。

#include <cv.h>
#include <highgui.h> //图像视频输出/输入头文件
using namespace std;
IplImage* AddGuassianNoise(IplImage* src)    //添加高斯噪声
{
IplImage* dst = cvCreateImage(cvGetSize(src), src->depth, src->nChannels);
IplImage* noise = cvCreateImage(cvGetSize(src), src->depth, src->nChannels);
CvRNG rng = cvRNG(-1);
cvRandArr(&rng, noise, CV_RAND_NORMAL, cvScalarAll(0), cvScalarAll(15));
cvAdd(src, noise, dst);
return dst;
}
IplImage* AddPepperNoise(IplImage* src)      //添加胡椒噪声，随机黑色点
{
IplImage* dst = cvCreateImage(cvGetSize(src), src->depth, src->nChannels);
cvCopy(src, dst);
for (int k = 0; k<8000; k++)
{
int i = rand() % src->height;
int j = rand() % src->width;
CvScalar s = cvGet2D(src, i, j);
if (src->nChannels == 1)
{
s.val[0] = 0;
}
else if (src->nChannels == 3)
{
s.val[0] = 0;
s.val[1] = 0;
s.val[2] = 0;
}
cvSet2D(dst, i, j, s);
}
return dst;
}
IplImage* AddSaltNoise(IplImage* src)       //添加盐噪声，随机白色点
{
IplImage* dst = cvCreateImage(cvGetSize(src), src->depth, src->nChannels);
cvCopy(src, dst);
for (int k = 0; k<8000; k++)
{
int i = rand() % src->height;
int j = rand() % src->width;
CvScalar s = cvGet2D(src, i, j);
if (src->nChannels == 1)
{
s.val[0] = 255;
}
else if (src->nChannels == 3)
{
s.val[0] = 255;
s.val[1] = 255;
s.val[2] = 255;
}
cvSet2D(dst, i, j, s);
}
return dst;
}
IplImage* AddPepperSaltNoise(IplImage* src)    //添加椒盐噪声，随机黑白点
{
IplImage* dst = cvCreateImage(cvGetSize(src), src->depth, src->nChannels);
cvCopy(src, dst);
for (int k = 0; k<8000; k++)
{
int i = rand() % src->height;
int j = rand() % src->width;
int m = rand() % 2;
CvScalar s = cvGet2D(src, i, j);
if (src->nChannels == 1)
{
if (m == 0)
{
s.val[0] = 255;
}
else
{
s.val[0] = 0;
}
}
else if (src->nChannels == 3)
{
if (m == 0)
{
s.val[0] = 255;
s.val[1] = 255;
s.val[2] = 255;
}
else
{
s.val[0] = 0;
s.val[1] = 0;
s.val[2] = 0;
}
}
cvSet2D(dst, i, j, s);
}
return dst;
}
//算术均值滤波器——模板大小5*5
IplImage* ArithmeticMeanFilter(IplImage* src)
{
IplImage* dst = cvCreateImage(cvGetSize(src), src->depth, src->nChannels);
cvSmooth(src, dst, CV_BLUR, 5);
return dst;
}
int main()
{
IplImage * test, *test_1, *test_2;
test = cvLoadImage("6013202130.jpg",0);//图片路径是 ConsoleApplication4 文件夹里，同时实验要求转为灰度图片
test_1 = cvCreateImage(cvSize((test->width), (test->height)), IPL_DEPTH_8U, 1); //创建图像，给指针赋值
test_2 = cvCreateImage(cvSize((test->width), (test->height)), IPL_DEPTH_8U, 1); //创建图像，给指针赋值
test_2 = AddGuassianNoise(test);
test_1 = ArithmeticMeanFilter(test_2);
cvNamedWindow("原图", CV_WINDOW_AUTOSIZE);
cvShowImage("原图", test);
cvNamedWindow("滤波后", CV_WINDOW_AUTOSIZE);
cvShowImage("滤波后", test_1);
cvNamedWindow("噪声后", CV_WINDOW_AUTOSIZE);
cvShowImage("噪声后", test_2);
cvWaitKey(0);//等待按键
cvDestroyWindow("zhang_fei_1");
cvDestroyWindow("zhang_fei_2");
cvDestroyWindow("zhang_fei_3");
cvReleaseImage(&test);//释放内存。 
cvReleaseImage(&test_1);
cvReleaseImage(&test_2);
return 0;
}