1 import coloreffect
3 class C(coloreffect.ColorEffect):
4 def colmod(self,r,g,b):
5 #ITU-R Recommendation BT.709
6 #l = 0.2125 * r + 0.7154 * g + 0.0721 * b
7 #NTSC and PAL
8 l = 0.299 * r + 0.587 * g + 0.114 * b
9 ig=int(round(l))
10 #coloreffect.debug('gs '+hex(r)+' '+hex(g)+' '+hex(b)+'%02x%02x%02x' % (ig,ig,ig))
11 return '%02x%02x%02x' % (ig,ig,ig)
13 c = C()
14 c.affect()