code: void convertW( Homography2D_F64 w , CameraPinhole c ) {
  		// inv(w) = K*K'
  		tmp.set(w);
  		CommonOps_DDF3.divide(tmp,tmp.a33);
  		CommonOps_DDF3.cholU(tmp);
  		CommonOps_DDF3.invert(tmp,K);
  		CommonOps_DDF3.divide(K,K.a33);
  
  		c.fx = K.a11;
  		c.fy = knownAspectRatio ? (K.a22 + c.fx*aspectRatio)/2.0 : K.a22;
  		c.skew = zeroSkew ? 0 : K.a12;
  		c.cx = principlePointOrigin ? 0 : K.a13;
  		c.cy = principlePointOrigin ? 0 : K.a23;
  	}
docs: Converts W into a pinhole camera model by finding the cholesky decomposition