Example #1
0
void process_image(PNG_Canvas_BW& image) {
    int width = image.get_width();
    int height = image.get_height();


    double kernel[5][5];
    double sum = 0;
    for (int x=0; x< 5; x++) {
        for (int y = 0; y < 5; y++) {
            kernel[x][y] = exp((-(x*x)+(y*y))/(2*sigma*sigma));
            sum += kernel[x][y];
        }
    }

    /*
    for (int x = 0; x<5; x++){
    	for(int y = 0; y < 5; y++){
    		printf(" %f ",kernel[x][y]);
    	}
    	printf("\n");
    }
    printf("%f\n",sum);
    */

    int K = 2;
    double s = 1.0/sum;


    //Make a new image canvas for the output to avoid conflicts
    PNG_Canvas_BW outputImage(width,height);

    for (int y = K; y < height-K-1; y++) {
        for (int x = K; x < width-K-1; x++) {
            int sum = 0;
            for (int j = -K; j <= K; j++) {
                for (int i = -K; i <= K; i++) {
                    int p = image.get_pixel(x+i,y+j);
                    int c = kernel[j+K][i+K];
                    sum += c * p;
                }
            }
            int q = round(s*sum);
            if (q < 0) q = 0;
            if (q > 255) q = 255;
            outputImage.set_pixel(x,y,q);
        }
    }









    image = outputImage;
}
Example #2
0
void process_image(PNG_Canvas_BW& image){
	int width = image.get_width();
	int height = image.get_height();


	
	//image dilatate with and then erode with H

	//Make a new image canvas for the output to avoid conflicts
	int new_w = width_in;
	int new_h = height_in;
	PNG_Canvas_BW imagenew(new_w,new_h);
	
	float wnw = ((double) width)/((double)new_w);
	float hnh = ((double) height)/((double)new_h);
	//printf("%f",wnw);
	for (int x = 0; x < new_w; x++){
		for (int y = 0; y < new_h; y++){
			int x0 = floor(x * wnw);
			int y0 = floor(y*hnh);
			int x1 = ceil(x*wnw);
			int y1 = ceil(y*hnh);
			int xs = x - x0;
			int ys = y - y0;
			int dx = 1 - xs;
			int dy = 1 - ys;
			int p0 = (image.get_pixel(x0,y0)*dx)+(image.get_pixel(x1,y0)*xs);
			int p1 = (image.get_pixel(x0,y1)*dx)+(image.get_pixel(x1,y1)*xs);
			int result = (p0 * dy) + (p1 *ys);
			if (result > 255) result = 128;
			if (result < 0) result = 128;
			imagenew.set_pixel(x,y,result);

		}
	}


			
			
	//Copy the result back into the provided image
	image = imagenew;
}
Example #3
0
void process_image(PNG_Canvas_BW& image){
	int width = image.get_width();
	int height = image.get_height();

	int h[256] = {0};
	for (int x =0; x < width; x++){
		for (int y = 0; y < height; y++){
			h[image.get_pixel(x,y)] = h[image.get_pixel(x,y)]+1;
		}
	}

	int H[256] = {0};
	for (int x =0; x < width; x++){
		for (int y = 0; y < height; y++){
			H[image[x][y]] = H[image[x][y]]+1;
		}
	}
	H[0] = h[0];
	for (int a = 1; a < 256; a++){
		H[a] = H[a-1] + H[a];
	}

	//gaussian distribution
	double normal[256] = {0};
	int sigma = 50;
	int m = 128;
	float sigmasqr2pi = sigma * sqrt(2*M_PI);
	float twosigma2 = 2 * sigma * sigma;
	for (int x = 0; x< 256; x++){
		normal[x] = exp((-pow((x-m),2))/twosigma2)/(sigmasqr2pi);
	}

	//inversed bell curve
	double gx[256] = {0};
	for (int b = 0; b < 256; b ++){
		int sigma = 50;
		int m = 128;
		float sigmasqr2pi = sigma * sqrt(2*M_PI);
		float twosigma2 = 2 * sigma * sigma;
		float gm = exp((-pow((m-m),2))/twosigma2)/(sigmasqr2pi);
		gx[b] = gm - normal[b];
		//printf("%f\n",gx[b]);
	}

	for (int b = 1; b < 256; b++){
		gx[b] = gx[b-1]+gx[b];
	}


	//for (int i = 0; i < 256; i++){
	//	printf("%f\n",gx[i]);
	//}


	int F[256] = {0};

	int n = width * height;
	int r = n/1;
	int i = 0;
	int c = 0;
	int j = 0;
	while (i < 256){
		if (c <= r*gx[j]){
			//printf("%f\n", r*normal[i]);
			c += h[i];
			F[i] = j;
			i = i + 1;
		} else {
			j = j + 1;
		}
	}






	//Make a new image canvas for the output to avoid conflicts
	PNG_Canvas_BW outputImage(width,height);
	
	for (int y = 0; y < height; y++){
		for (int x = 0; x < width; x++){
			outputImage[x][y] = F[image[x][y]];
		}
	}





	image = outputImage;
}