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asked 2014-05-13 10:28:41 -0600

abir gravatar image

How to cut an image in small images with opencv !!!

Hello I need to cut an image in small images with opencv for my algo please help me . thank you

How to cut an image in small images with opencv !!!

Hello I need to cut an image in small images with opencv for my algo ! please help me . thank you

How to cut an image in small images with opencv !!!

Hello I need to cut an image in small images with opencv for my algo ! please help me . thank you 

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/core/core.hpp"

using namespace std;
using namespace cv;

int main()
{
Mat image,I2;

image = imread("crop_uEyeImg1.tif",1);
if(image.empty())
{
cout << "Could not open or find the image" << std::endl ;
return -1;
}

/// Convert it to gray
//cvtColor( image, image, CV_RGB2GRAY );
//resize(image,image,Size(0,0),0.5,0.5,INTER_LINEAR);
namedWindow("Image", CV_WINDOW_AUTOSIZE );
imshow("Image", image);
/// Generate grad_x and grad_y
Mat grad_x, grad_y;
Mat abs_grad_x, abs_grad_y;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
Mat grad;

   // get the image data
 int height = image.rows;
 int width = image.cols;

 printf("Processing a %dx%d image\n",height,width);

cv :: Size smallSize ( 110 , 70 );

std :: vector < Mat > smallImages ;


for  ( int y =  0 ; y < image . rows ; y += smallSize . height )
{
    for  ( int x =  0 ; x < image . cols ; x += smallSize . width )
    {
        cv :: Rect rect =   cv :: Rect ( x , y , smallSize . width , smallSize . height );
        smallImages . push_back ( cv :: Mat ( image , rect ));



///// Gradient X
////Scharr( image, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
Sobel( I2, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_x, abs_grad_x );

///// Gradient Y
//// Scharr( image, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
Sobel( I2, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_y, abs_grad_y );
///// Total Gradient (approximate)

addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad );

namedWindow("ImageSobel", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobel", grad );

namedWindow("ImageSobelGx", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGx", abs_grad_x );

namedWindow("ImageSobelGy", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGy", abs_grad_y );

// // Calculate orientations of gradients --> in degrees
// //Loop over all matrix values and calculate the accompanied orientation

Mat orientation = Mat::zeros(abs_grad_x.rows, abs_grad_y.cols, CV_32F); //to store the gradients

grad_x.convertTo(grad_x,CV_32F);
grad_y.convertTo(grad_y,CV_32F);
//phase(grad_x, grad_y, orientation);
//cv::normalize(orientation, orientation, 0x00, 0xFF, cv::NORM_MINMAX, CV_8U);

////namedWindow("Orientation", CV_WINDOW_AUTOSIZE );
////imshow( "Orientation", orientation );

phase(grad_x, grad_y, orientation, true);
ofstream file1("orient.txt"); file1 << orientation; file1.close();
  }
}
waitKey(0);
return 0;
}

How to cut an image in small images with opencv !!!

Hello I need to cut an image in small images with opencv for my algo ! please help me . thank you 

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/core/core.hpp"

using namespace std;
using namespace cv;

int main()
{
Mat image,I2;
image;

image = imread("crop_uEyeImg1.tif",1);
if(image.empty())
{
cout << "Could not open or find the image" << std::endl ;
return -1;
}

/// Convert it to gray
//cvtColor( image, image, CV_RGB2GRAY );
//resize(image,image,Size(0,0),0.5,0.5,INTER_LINEAR);
namedWindow("Image", CV_WINDOW_AUTOSIZE );
imshow("Image", image);
/// Generate grad_x and grad_y
Mat grad_x, grad_y;
Mat abs_grad_x, abs_grad_y;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
Mat grad;

   // get the image data
 int height = image.rows;
 int width = image.cols;

 printf("Processing a %dx%d image\n",height,width);

cv :: Size smallSize ( 110 , 70 );

std :: vector < Mat > smallImages ;


for  ( int y =  0 ; y < image . rows ; y += smallSize . height )
{
    for  ( int x =  0 ; x < image . cols ; x += smallSize . width )
    {
        cv :: Rect rect =   cv :: Rect ( x , y , smallSize . width , smallSize . height );
        smallImages . push_back ( cv :: Mat ( image , rect ));



///// Gradient X
////Scharr( image, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
Sobel( I2, image, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_x, abs_grad_x );

///// Gradient Y
//// Scharr( image, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
Sobel( I2, image, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_y, abs_grad_y );
///// Total Gradient (approximate)

addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad );

namedWindow("ImageSobel", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobel", grad );

namedWindow("ImageSobelGx", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGx", abs_grad_x );

namedWindow("ImageSobelGy", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGy", abs_grad_y );

// // Calculate orientations of gradients --> in degrees
// //Loop over all matrix values and calculate the accompanied orientation

Mat orientation = Mat::zeros(abs_grad_x.rows, abs_grad_y.cols, CV_32F); //to store the gradients

grad_x.convertTo(grad_x,CV_32F);
grad_y.convertTo(grad_y,CV_32F);
//phase(grad_x, grad_y, orientation);
//cv::normalize(orientation, orientation, 0x00, 0xFF, cv::NORM_MINMAX, CV_8U);

////namedWindow("Orientation", CV_WINDOW_AUTOSIZE );
////imshow( "Orientation", orientation );

phase(grad_x, grad_y, orientation, true);
ofstream file1("orient.txt"); file1 << orientation; file1.close();
  }
}
waitKey(0);
return 0;
}

How to cut an image in small images with opencv !!!

C:\fakepath\small image.jpgHello I need to cut an image in small images with opencv for my algo ! please help me . thank you 

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/core/core.hpp"

using namespace std;
using namespace cv;

int main()
{
Mat image;

image = imread("crop_uEyeImg1.tif",1);
if(image.empty())
{
cout << "Could not open or find the image" << std::endl ;
return -1;
}

/// Convert it to gray
//cvtColor( image, image, CV_RGB2GRAY );
//resize(image,image,Size(0,0),0.5,0.5,INTER_LINEAR);
namedWindow("Image", CV_WINDOW_AUTOSIZE );
imshow("Image", image);
/// Generate grad_x and grad_y
Mat grad_x, grad_y;
Mat abs_grad_x, abs_grad_y;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
Mat grad;

   // get the image data
 int height = image.rows;
 int width = image.cols;

 printf("Processing a %dx%d image\n",height,width);

cv :: Size smallSize ( 110 , 70 );

std :: vector < Mat > smallImages ;


for  ( int y =  0 ; y < image . rows ; y += smallSize . height )
{
    for  ( int x =  0 ; x < image . cols ; x += smallSize . width )
    {
        cv :: Rect rect =   cv :: Rect ( x , y , smallSize . width , smallSize . height );
        smallImages . push_back ( cv :: Mat ( image , rect ));



///// Gradient X
////Scharr( image, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
Sobel( image, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_x, abs_grad_x );

///// Gradient Y
//// Scharr( image, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
Sobel( image, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_y, abs_grad_y );
///// Total Gradient (approximate)

addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad );

namedWindow("ImageSobel", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobel", grad );

namedWindow("ImageSobelGx", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGx", abs_grad_x );

namedWindow("ImageSobelGy", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGy", abs_grad_y );

// // Calculate orientations of gradients --> in degrees
// //Loop over all matrix values and calculate the accompanied orientation

Mat orientation = Mat::zeros(abs_grad_x.rows, abs_grad_y.cols, CV_32F); //to store the gradients

grad_x.convertTo(grad_x,CV_32F);
grad_y.convertTo(grad_y,CV_32F);
//phase(grad_x, grad_y, orientation);
//cv::normalize(orientation, orientation, 0x00, 0xFF, cv::NORM_MINMAX, CV_8U);

////namedWindow("Orientation", CV_WINDOW_AUTOSIZE );
////imshow( "Orientation", orientation );

phase(grad_x, grad_y, orientation, true);
ofstream file1("orient.txt"); file1 << orientation; file1.close();
  }
}
waitKey(0);
return 0;
}
click to hide/show revision 6
retagged

updated 2017-10-09 01:56:11 -0600

sturkmen gravatar image

How to cut an image in small images with opencv !!!

C:\fakepath\small image.jpgHello I need to cut an image in small images with opencv for my algo ! please help me . thank you 

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/core/core.hpp"

using namespace std;
using namespace cv;

int main()
{
Mat image;

image = imread("crop_uEyeImg1.tif",1);
if(image.empty())
{
cout << "Could not open or find the image" << std::endl ;
return -1;
}

/// Convert it to gray
//cvtColor( image, image, CV_RGB2GRAY );
//resize(image,image,Size(0,0),0.5,0.5,INTER_LINEAR);
namedWindow("Image", CV_WINDOW_AUTOSIZE );
imshow("Image", image);
/// Generate grad_x and grad_y
Mat grad_x, grad_y;
Mat abs_grad_x, abs_grad_y;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
Mat grad;

   // get the image data
 int height = image.rows;
 int width = image.cols;

 printf("Processing a %dx%d image\n",height,width);

cv :: Size smallSize ( 110 , 70 );

std :: vector < Mat > smallImages ;


for  ( int y =  0 ; y < image . rows ; y += smallSize . height )
{
    for  ( int x =  0 ; x < image . cols ; x += smallSize . width )
    {
        cv :: Rect rect =   cv :: Rect ( x , y , smallSize . width , smallSize . height );
        smallImages . push_back ( cv :: Mat ( image , rect ));



///// Gradient X
////Scharr( image, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
Sobel( image, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_x, abs_grad_x );

///// Gradient Y
//// Scharr( image, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
Sobel( image, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_y, abs_grad_y );
///// Total Gradient (approximate)

addWeighted( abs_grad_x, 0.5, abs_grad_y, 0.5, 0, grad );

namedWindow("ImageSobel", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobel", grad );

namedWindow("ImageSobelGx", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGx", abs_grad_x );

namedWindow("ImageSobelGy", CV_WINDOW_AUTOSIZE );
imshow( "ImageSobelGy", abs_grad_y );

// // Calculate orientations of gradients --> in degrees
// //Loop over all matrix values and calculate the accompanied orientation

Mat orientation = Mat::zeros(abs_grad_x.rows, abs_grad_y.cols, CV_32F); //to store the gradients

grad_x.convertTo(grad_x,CV_32F);
grad_y.convertTo(grad_y,CV_32F);
//phase(grad_x, grad_y, orientation);
//cv::normalize(orientation, orientation, 0x00, 0xFF, cv::NORM_MINMAX, CV_8U);

////namedWindow("Orientation", CV_WINDOW_AUTOSIZE );
////imshow( "Orientation", orientation );

phase(grad_x, grad_y, orientation, true);
ofstream file1("orient.txt"); file1 << orientation; file1.close();
  }
}
waitKey(0);
return 0;
}
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