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1、 Box filtering ：boxFilter Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "F:/images/renwu1.jpg";
std::string boxFilter_original = "boxFilterOriginal";
std::string boxFilter_result = "boxFilterResult";

static void test()
{
    
	// 1、 Read images 
	Mat image = imread(image_path);

	//2、 create a window 
	namedWindow(boxFilter_original, WINDOW_AUTOSIZE);
	namedWindow(boxFilter_result, WINDOW_AUTOSIZE);
	//3、 Show the original 
	imshow(boxFilter_original, image);

	//4、 Perform block filtering operation 
	Mat result;
	boxFilter(image, result, -1, Size(5, 5));

	//5、 Show renderings 
	imshow(boxFilter_result, result);

	waitKey(0);
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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2、 Mean filtering ：blur Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "F:/images/renwu1.jpg";
std::string blur_original = "blurOriginal";
std::string blur_result = "blurResult";


static void  test()
{
    
	//1、 Load the original drawing 
	Mat srcImage = imread(image_path);

	//2、 Show the original image 
	imshow(blur_original, srcImage);

	//3、 Perform mean filtering operation 
	Mat dstImage;
	blur(srcImage, dstImage, Size(7, 7));

	//4、 Show renderings 
	imshow(blur_result, dstImage);

	waitKey(0);
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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3、 Gauss filtering ：GaussianBlur Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "F:/images/renwu1.jpg";
std::string gaussian_blur_original = "GaussianBlurOriginal";
std::string gaussian_blur_result = "GaussianBlurResult";

static void test()
{
    
	//1、  Load original 
	Mat image = imread(image_path);

	//2、 create a window 
	namedWindow(gaussian_blur_original);
	namedWindow(gaussian_blur_result);

	//3、 Show the original 
	imshow(gaussian_blur_original, image);

	//4、 Gaussian filtering operation 
	Mat result;
	GaussianBlur(image, result, Size(5, 5), 0, 0);

	//5、 Show renderings 
	imshow(gaussian_blur_result, result);

	waitKey(0);
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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4、 Comprehensive examples ： Image linear filtering

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;
using namespace std;

std::string image_path = "F:/images/renwu1.jpg";
std::string image_original = "Original";
std::string boxFilter_result = "boxFilterResult";
std::string blur_result = "blurResult";
std::string gaussian_blur_result = "GaussianBlurResult";


Mat g_srcImage, g_dstImage1, g_dstImage2, g_dstImage3;// Store pictures Mat type 
int g_nBoxFilterValue = 3;  // Block filter parameter value 
int g_nMeanBlurValue = 3;  // Mean filter parameter value 
int g_nGaussianBlurValue = 3;  // Gaussian filter parameter value 


// Callback function 
static void FunBoxFilter(int, void *);		// Mean filtering 
static void FunMeanBlur(int, void *);		// Mean filtering 
static void FunGaussianBlur(int, void *);	// Gauss filtering 



static void  test()
{
    
	// change console The font color 
	system("color 5F");
	//1、  Load original 
	g_srcImage = imread(image_path, 1);
	if (!g_srcImage.data) {
     cout << "not load image!! \n"; return; }

	//2、 Clone the original image to three Mat Type in the 
	g_dstImage1 = g_srcImage.clone();
	g_dstImage2 = g_srcImage.clone();
	g_dstImage3 = g_srcImage.clone();

	//3、 Show the original 
	namedWindow(image_original, 1);
	imshow(image_original, g_srcImage);


	//=================【<1> Box filtering 】==================
	// create a window 
	namedWindow(boxFilter_result, 1);
	// Create a trackbar 
	createTrackbar(" Kernel value ：", boxFilter_result, &g_nBoxFilterValue, 40, FunBoxFilter);
	FunBoxFilter(g_nBoxFilterValue, 0);
	//================================================

	//=================【<2> Mean filtering 】==================
	// create a window 
	namedWindow(blur_result, 1);
	// Create a trackbar 
	createTrackbar(" Kernel value ：", blur_result, &g_nMeanBlurValue, 40, FunMeanBlur);
	FunMeanBlur(g_nMeanBlurValue, 0);
	//================================================

	//=================【<3> Gauss filtering 】=====================
	// create a window 
	namedWindow(gaussian_blur_result, 1);
	// Create a trackbar 
	createTrackbar(" Kernel value ：", gaussian_blur_result, &g_nGaussianBlurValue, 40, FunGaussianBlur);
	FunGaussianBlur(g_nGaussianBlurValue, 0);
	//================================================


	// Output some help information 
	cout << endl << "\t The successful running , Please adjust the scroll bar to observe the image effect ~\n\n"
		<< "\t Press down “q” Key time , Program exit .\n";

	// Press down “q” Key time , Program exit 
	while (char(waitKey(1)) != 'q') {
    }

	return;
}

int main()
{
    
	test();
	system("pause");
	return 0;
}


static void FunBoxFilter(int, void *)
{
    
	// Block filter operation 
	boxFilter(g_srcImage, g_dstImage1, -1, Size(g_nBoxFilterValue + 1, g_nBoxFilterValue + 1));
	// Display window 
	imshow(boxFilter_result, g_dstImage1);
}


static void FunMeanBlur(int, void *)
{
    
	// Mean filtering operation 
	blur(g_srcImage, g_dstImage2, Size(g_nMeanBlurValue + 1, g_nMeanBlurValue + 1), Point(-1, -1));
	// Display window 
	imshow(blur_result, g_dstImage2);
}


static void FunGaussianBlur(int, void *)
{
    
	// Gaussian filtering operation 
	GaussianBlur(g_srcImage, g_dstImage3, Size(g_nGaussianBlurValue * 2 + 1, g_nGaussianBlurValue * 2 + 1), 0, 0);
	// Display window 
	imshow(gaussian_blur_result, g_dstImage3);
}

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5、 median filtering ：medianBlur Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "F:/images/renwu1.jpg";
std::string median_blur_original = "medianBlurOriginal";
std::string median_blur_result = "medianBlurResult";

static void test()
{
    
	//1、  Load original 
	Mat image = imread(image_path);

	//2、 create a window 
	namedWindow(median_blur_original,WINDOW_AUTOSIZE);
	namedWindow(median_blur_result,WINDOW_AUTOSIZE);

	//3、 Show the original 
	imshow(median_blur_original, image);

	// Carry out median filtering operation 
	Mat result;
	medianBlur(image, result, 7);

	//4、 Show renderings 
	imshow(median_blur_result, result);

	waitKey(0);
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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6、 Bilateral filtering ：bilateralFilter Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "F:/images/renwu1.jpg";
std::string bilateralFilter_original = "bilateralFilterOriginal";
std::string bilateralFilter_result = "bilateralFilterResult";

static void test()
{
    
	//1、  Load original 
	Mat srcImage = imread(image_path);

	//2、 create a window 
	namedWindow(bilateralFilter_original);
	namedWindow(bilateralFilter_result);

	//3、 Show the original 
	imshow(bilateralFilter_original, srcImage);

	//4、 Perform bilateral filtering operation 
	Mat result;
	bilateralFilter(srcImage, result, 25, 25 * 2, 25 / 2);

	//5、 Show renderings 
	imshow(bilateralFilter_result, result);

	waitKey(0);
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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7、 Comprehensive examples ： Image filtering

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;
using namespace std;

std::string image_path = "F:/images/renwu1.jpg";
std::string image_original = "Original";
std::string median_blur_result = "medianBlurResult";
std::string bilateralFilter_result = "bilateralFilterResult";

Mat g_srcImage, g_dstImage1, g_dstImage2;
int g_nMedianBlurValue = 10;       // Median filter parameter value 
int g_nBilateralFilterValue = 10;  // Bilateral filtering parameter value 



// Callback function 
static void FunMedianBlur(int, void *);		// Median filter 
static void FunBilateralFilter(int, void *);// Bilateral filter 


static void test()
{
    
	system("color 4F");
	//  Load original 
	g_srcImage = imread(image_path, 1);
	if (!g_srcImage.data) {
     std::cout << "image not load! \n"; return; }

	// Clone the original image to four Mat Type in the 
	g_dstImage1 = g_srcImage.clone();
	g_dstImage2 = g_srcImage.clone();
	// Show the original 
	namedWindow(image_original, WINDOW_AUTOSIZE);
	imshow(image_original, g_srcImage);

	//=================【<2> median filtering 】===========================
	// create a window 
	namedWindow(median_blur_result, WINDOW_AUTOSIZE);
	// Create a trackbar 
	createTrackbar(" Parameter values ：", median_blur_result, &g_nMedianBlurValue, 50, FunMedianBlur);
	FunMedianBlur(g_nMedianBlurValue, 0);
	//=======================================================


	//=================【<3> Bilateral filtering 】===========================
	// create a window 
	namedWindow(bilateralFilter_result, 1);
	// Create a trackbar 
	createTrackbar(" Parameter values ：", bilateralFilter_result, &g_nBilateralFilterValue, 50, FunBilateralFilter);
	FunBilateralFilter(g_nBilateralFilterValue, 0);
	//=======================================================


	// Output some help information 
	cout << endl << "\t The successful running , Please adjust the scroll bar to observe the image effect ~\n\n"
		<< "\t Press down “q” Key time , Program exit .\n";
	while (char(waitKey(1)) != 'q') {
    }

	return;
}

int main()
{
    
	test();
	system("pause");
	return 0;
}


static void FunMedianBlur(int, void *)
{
    
	medianBlur(g_srcImage, g_dstImage1, g_nMedianBlurValue * 2 + 1);
	imshow(median_blur_result, g_dstImage1);
}


static void FunBilateralFilter(int, void *)
{
    
	bilateralFilter(g_srcImage, g_dstImage2, g_nBilateralFilterValue, g_nBilateralFilterValue * 2, g_nBilateralFilterValue / 2);
	imshow(bilateralFilter_result, g_dstImage2);
}

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8、 inflation ：dilate Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "1.jpg";
std::string dilate_original = "dilateOriginal";
std::string dilate_result = "dilateResult";

static void test()
{
    

	//1、 Load original  
	Mat src_image = imread(image_path);

	//2、 create a window  
	namedWindow(dilate_original, WINDOW_AUTOSIZE);
	namedWindow(dilate_result, WINDOW_AUTOSIZE);

	//3、 Show the original 
	imshow(dilate_original, src_image);

	//4、 Perform the expansion operation  
	Mat element = getStructuringElement(MORPH_RECT, Size(15, 15));
	Mat result;
	dilate(src_image, result, element);

	//6、 Show renderings  
	imshow(dilate_result, result);

	waitKey(0);
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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9、 corrosion ：erode Use of functions

result

C++ Code example

#include<opencv2/opencv.hpp>
#include<string>
using namespace cv;

std::string image_path = "1.jpg";
std::string erode_original = "erodeOriginal";
std::string erode_result = "erodeResult";

static void test()
{
    
	//1、 Load original  
	Mat srcImage = imread(image_path);
	//2、 Show the original 
	imshow(erode_original, srcImage);
	//3、 Carry out corrosion operation  
	Mat element = getStructuringElement(MORPH_RECT, Size(15, 15));
	Mat dstImage;
	erode(srcImage, dstImage, element);
	//4、 Show renderings  
	imshow(erode_result, dstImage);
	waitKey(0); 
}

int main()
{
    
	test();
	system("pause");
	return 0;
}

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