code: public boolean computeRectifyingHomography( DMatrixRMaj H ) {
  		H.reshape(4,4);
  
  		// insert the results into H
  		// H = [K 0;-p'*K 1 ]
  		H.zero();
  		for (int i = 0; i < 3; i++) {
  			for (int j = i; j < 3; j++) {
  				H.set(i,j,k.get(i,j));
  			}
  		}
  		// p and k have different scales, fix that
  		H.set(3,0, -(p.a1*k.a11 + p.a2*k.a21 + p.a3*k.a31));
  		H.set(3,1, -(p.a1*k.a12 + p.a2*k.a22 + p.a3*k.a32));
  		H.set(3,2, -(p.a1*k.a13 + p.a2*k.a23 + p.a3*k.a33));
  		H.set(3,3,1);
  
  		return true;
  	}
docs: Computes the rectifying homography from the decomposed Q
  
  H = [K 0; -p'*K 1]  see Pg 460