CodeBrawl pixelating contest entry

pixelate.rb

require 'chunky_png'

image = ChunkyPNG::Image.from_file('input.png')
width = image.width
height = image.height

size_factor = 10

pixelated_width = width / size_factor
pixelated_height = height / size_factor

for x in 0.upto(pixelated_width - 1)
    for y in 0.upto(pixelated_height - 1)             #For each block on the pixelated output image
        min_x_real = x * size_factor                  #we get the range of pixels from the original image
        max_x_real = min_x_real + size_factor - 1
        min_y_real = y * size_factor
        max_y_real = min_y_real + size_factor - 1
        count = 0

        total_r = 0
        total_g = 0
        total_b = 0

        for x_real in min_x_real..max_x_real         #For each pixel on the original image corresponding
            for y_real in min_y_real..max_y_real     #to the current block of the pixelated output
                count += 1                           #we get the sum of the r, g and b components
                color = image[x_real, y_real]
                total_r += ChunkyPNG::Color.r color
                total_g += ChunkyPNG::Color.g color
                total_b += ChunkyPNG::Color.b color
            end
        end
        total_r /= count                             #Average colors
        total_g /= count
        total_b /= count
        for x_real in min_x_real..max_x_real         #Paint the block color on the original image
            for y_real in min_y_real..max_y_real
                image[x_real, y_real] = 
                    ChunkyPNG::Color.rgb(total_r, total_g, total_b)
            end
        end
    end
end

image.save('output.png')