Looking first at modification of the alpha value, for each pixel in the design image {HEAD ~ a modified alpha value} for {TAIL ~ that pixel} is calculated based on the value of MIN and the original alpha of the pixel as follows: 
for
Looking first at modification of the alpha value , for each pixel in the design image { HEAD ~ a modified alpha value } for { TAIL ~ that pixel } is calculated based on the value of MIN and the original alpha of the pixel as follows :
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH