“…A differential vector for point (x i , y i ) is determined by taking differences (or deltas) between the current point (x i , y i ) and its previous point on the line segment (x i-1 , y i-1 ) [5]. For example, consider a line with coordinates (1, 1), (2, 3), (3,2) and (5,4). The line is encoded using differential vectors as follows: (1,1) , (1,2) , (1,-1) and (2,2) using the formula of Delta(x) = X i -X (i-1) and Delta(y) = Y i -Y (i-1) .…”