Homographies of points and lines
	Computed by 3x3 matrix multiplication • To transform a point:  p’ = Hp • To transform a line:  lp=0 ® l’p’=0
		– 0 = lp = lH-1Hp = lH-1p’ Þ  l’ = lH-1 – lines are transformed by postmultiplication of H-1