from PIL import Image, ImageFilter
 
original = Image.open("images/books-edited.jpg") # load an image from the hard drive
changed = original.convert("L") # Convert from RGB to YCbCr
pixarr = changed.load() # load pixels from image into array

for j in range(changed.size[1]): # For every single pixel
	for i in range (changed.size[0]):
		#print(pixarr[i,j])
		pixarr[i,j] = 125 # Change the pixel to grey
		#print(pixarr[i,j])

changed.show() # will print just grey

# helpful documentation for this library @ http://effbot.org/imagingbook/image.htm

@@ -143,17 +143,21 @@
 onvert(%22
-L
+YCbCr
 %22) # Con
@@ -362,24 +362,84 @@
 %0A%09%09p
-ixarr%5Bi,j%5D = 125
+lace=pixarr%5Bi,j%5D%5B1%5D%0A%09%09holder=pixarr%5Bi,j%5D%5B2%5D%0A%09%09pixarr%5Bi,j%5D = (0,place,holder)
  # C
@@ -452,21 +452,17 @@
 the 
-pixel to grey
+luminance
 %0A%09%09#
@@ -513,17 +513,119 @@
 int 
-just grey
+it as dark%0A%0Anew = changed.convert(%22RGB%22) # Convert back to RGB%0Anew.show() # Should be equal to the changed one 
 %0A%0A# 

Update piltest.py