how to program median-filter processing on 24 bitmap instead of 8 bitmap?

Hi,guys!
i have done a little change to the code snippets from some website capable of doing median-filter processing on 24 bitmap,such code as following:

Code:

	typedef struct element{
		UCHAR b;
		UCHAR g;
		UCHAR r;
	}element;

void CIMGutility::_medianfilter(const element* image, element* result, int N, int M)
{
	//   Move window through all elements of the image
	for (int m = 1; m < M - 1; ++m)
		for (int n = 1; n < N - 1; ++n)
		{
			//   Pick up window elements
			int k = 0;
			element window[9];
			for (int j = m - 1; j < m + 2; ++j)
				for (int i = n - 1; i < n + 2; ++i)
					window[k++] = image[j * N + i];
			//   Order elements (only half of them)
			for (int j = 0; j < 5; ++j)
			{
				//   Find position of minimum element
				int min = j;
				for (int l = j + 1; l < 9; ++l)
					if (window[l].b < window[min].b)
						min = l;
				//   Put found minimum element in its place
				byte temp = window[j].b;
				window[j].b = window[min].b;
				window[min].b = temp;


				min = j;
				for (int l = j + 1; l < 9; ++l)
					if (window[l].g < window[min].g)
						min = l;
				//   Put found minimum element in its place
				temp = window[j].g;
				window[j].g = window[min].g;
				window[min].g = temp;


				min = j;
				for (int l = j + 1; l < 9; ++l)
					if (window[l].r < window[min].r)
						min = l;
				//   Put found minimum element in its place
				temp = window[j].r;
				window[j].r = window[min].r;
				window[min].r = temp;
			}
			//   Get result - the middle element

			result[(m - 1) * (N - 2) + n - 1] = window[4];
		}
}

but final output image doesn't seem to be correct result. so anything wrong with the above code.thank you !