学步园

论文作者 Derek Bradley*   Gerhard Roth

论文给的伪代码：

void vvAdaptiveThreshold( IplImage* inImg, IplImage* outImg)
{
	int S = inImg->width >> 5;
	int T = 10;

	char *input, *bin;
	input = inImg->imageData;
	bin = outImg->imageData;

	int width = inImg->width;
	int height = inImg->height;

	unsigned long* integralImg = 0;
	int i, j;
	long sum=0;
	int count=0;
	int index;
	int x1, y1, x2, y2;
	int s2 = S/2;

	//bin = new unsigned char[width*height];
	// create the integral image
	integralImg = (unsigned long*)malloc(width*height*sizeof(unsigned long*));
	for (i=0; i<width; i++)
	{
		// reset this column sum
		sum = 0;
		for (j=0; j<height; j++)
		{
			index = j*width+i;
			sum += input[index];
			if (i==0)
				integralImg[index] = sum;
			else
				integralImg[index] = integralImg[index-1] + sum;
		}
	}
	// perform thresholding
	for (i=0; i<width; i++)
	{
		for (j=0; j<height; j++)
		{
			index = j*width+i;
			// set the SxS region
			x1=i-s2; x2=i+s2;
			y1=j-s2; y2=j+s2;
			// check the border
			if (x1 < 0) x1 = 0;
			if (x2 >= width) x2 = width-1;
			if (y1 < 0) y1 = 0;
			if (y2 >= height) y2 = height-1;
			count = (x2-x1)*(y2-y1);
			// I(x,y)=s(x2,y2)-s(x1,y2)-s(x2,y1)+s(x1,x1)
			sum = integralImg[y2*width+x2] -
				integralImg[y1*width+x2] -
				integralImg[y2*width+x1] +
				integralImg[y1*width+x1];
			if ((long)(input[index]*count) < (long)(sum*(100-T)/100))
				bin[index] = 0;
			else
				bin[index] = 255;
		}
	}
	free (integralImg);
}

这个源码请参考  http://blog.csdn.net/hhygcy/article/details/4280165

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论文效果

而  我跑了下：