-- maximumSharpen_Luminance.lua
-- search for maximum luminance difference and replace current pixel
-- with pixel having max lum difference
-- author: Sinisa Petric, (pixopedia@sigmapi-design.com), 2008

image_OUT = 0
image_INP = 1

size = 2

function maxlumdiff (x,y, size)
   local i, j, x_pos, y_pos, lum, lum_max, lum_center
   x_pos, y_pos = x, y   
   lum_max = 0  
   lum_center =   fp24_getImageLuminance01(image_INP, x, y)
   for i=-size,size do
       for j=-size,size do
       lum = math.abs(fp24_getImageLuminance01(image_INP, x+j, y+i) - lum_center)
       if lum > lum_max then
            lum_max = lum
            x_pos, y_pos = x + j, y + i 		             
         end   
      end
   end
   return x_pos, y_pos
end
for y=0, vp24_height-1 do
   for x= 0, vp24_width-1 do
       new_x, new_y = maxlumdiff(x, y, size) 
       r, g, b = fp24_getImageRGB(image_INP, new_x, new_y)
       fp24_setImageRGB (image_OUT, x, y, r, g, b)
   end
   fp24_showProgress (y, vp24_height)
end