original photo
greyscale photo
To turn the color photo into a greyscale one, I averaged the values of the three color channels
blurred greyscale photo
To blur the image, I used the average pixel values within a 2 pixel radius (the original pixel and the 24 closest pixels to it). The above image is the result of 2 rounds of this blurring algorithm. I found that this algorithm blurred the image faster than the 8 neighbors algorithm.