Average low pass filter for 24-bit color Image

The average low-pass filter is a algorithm where we take average of all adjacent pixels for the each pixel.We start it from the pixel [1][1] and to the pixel[h-2][w-2] and the boundary pixels copy same as available in input image.So we get a filter which takes a pixel and take average of all 8-neighbor and put it into the pixel.Thus if a pixel having a higher value than its neighbors it  is reduced thus there is only  a pass for the low value pixels and it reduces the pixels with high value.So it is called low pass filter.Here is the input and output image used for the program .There is a slight change in input and output image which very difficult to see.

Input Image

Output Image