Matlab C: differenze tra le versioni

#include "engine.h"

#include <iostream>

using namespace std;

unsigned char** getRawGrayScaleImage(mxArray *);

void putRawGrayScaleImageInMatlab(unsigned char ** mat, int n);

void countAboveBelowThreshold(unsigned char ** mat, int n, int th);

void invertImage(unsigned char ** mat, int n);

//declare pointer to engine

Engine *eng;

int main() {

	//initialize it with the handle to a new session of MATLAB engine

	eng = engOpen(NULL);

	engSetVisible(eng, 0);

	//check status 

	if (!(eng)) {

		exit(-1);

	}

	//open image in MATLAB engine (using image path)

	engEvalString(eng, "I = imread('C:\\Users\\Irio\\Desktop\\\Esercizio_05122019\\MATLAB&VISUAL STUDIO\\codes\\Heatmap.jpg');");

	//show image I

	engEvalString(eng, "imshow(I)");

	//wait engine

	system("PAUSE");

	//....manage your matrix in MATLAB (crop and convert)

	// MATLAB functions:

	// imcrop - creates a crop of the image

	engEvalString(eng, "I = imcrop(I,[276,279,844,844]);");

	engEvalString(eng, "imshow(I)");

	system("PAUSE");

	// rgb2gray - convert RGB image or colormap to grayscale.

	engEvalString(eng, "I = rgb2gray(I);");

	engEvalString(eng, "imshow(I)");

	system("PAUSE");

	//get mxArray of the image (C++ style)

	mxArray *imageML = engGetVariable(eng, "I");

	unsigned char **rawimage = getRawGrayScaleImage(imageML);

	//....manage your matrix in C++ 

	// count and print elements above and below a threshold value

	countAboveBelowThreshold(rawimage, 845, 127);

	system("pause");

	// invert image

	invertImage(rawimage, 845);

	system("pause");

	//put image back in MATLAB

	putRawGrayScaleImageInMatlab(rawimage, 845);

	//show image

	engEvalString(eng, "imshow(I)");

	system("pause");

	//close the session

	engClose(eng);

	return 0;

}

//extract image from mxArray pointer

unsigned char** getRawGrayScaleImage(mxArray *imagePtr) {

	int n = (int)mxGetN(imagePtr);

	unsigned char **mat = new unsigned char*[n];

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

		mat[i] = new unsigned char[n];

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

		for (int j = 0; j < n; j++) {

			mat[i][j] = *((unsigned char*)mxGetData(imagePtr) + i + j*n);

		}

	return mat;

}

//create mxArray from image

void putRawGrayScaleImageInMatlab(unsigned char ** mat, int n) {

	mxArray *matrix = mxCreateNumericMatrix(n, n, mxUINT8_CLASS, mxREAL);

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

		for (int j = 0; j < n; j++) {

			unsigned char *data = (unsigned char*)mxGetData(matrix) + i + j*n;

			*data = mat[i][j];

		}

	engPutVariable(eng, "I", matrix);

}

// count elements over and under threshold

void countAboveBelowThreshold(unsigned char ** mat, int n, int th) {

	int above = 0;

	int below = 0;

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

		for (int j = 0; j < n; j++) {

			if (mat[i][j] <= th)

				below++;

			else

				above++;

		}

	cout << "Threshold: " << th << endl;

	cout << "Elements above the threshold: " <<  above << endl;

	cout << "Elements below the threshold: "<< below << endl;

}

// invert image

void invertImage(unsigned char ** mat, int n) {

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

		for (int j = 0; j < n; j++) {

			mat[i][j] = 255 - mat[i][j];

		}

}