I pick up 4 correspondence point in 2 image: im1 and im2. I calculated the Homogeneous matrix H. In this case, I used normalized DLT algorithm to get H. Here: im2=H*im1 Then I follow that command as above to display the im2' from im1 by multiply with H. I just want to compare im2' and im2. But it does not work at all, As soon as I get the im2', it can not be displayed, maybe the problem is from the matrix H which is normalized. anybody can help me? Thank in advanced!