From: Bc on
"chee ali" <chase_the_dawn_2000(a)yahoo.com> wrote in message <hhl32n$e1d$1(a)fred.mathworks.com>...
> hi,i want 2 ask somthing about homography.i want to calculate homography matrix H,the equation is x&#8217;=Hx.
> x&#8217; is 3xN set of homogeneous points,now i am not getting the point that how to calculate this 3xN set of homogeneous points.
> please give me some idea.i hope you ill rep.

I have a feeling that what you want is to take point from your image using ginput and then used those points for the homography. This would probably mean that you will get the pixel coordinates (xi,yi) for each point and append the 1, to make them homogeneous:

(x1,y1,1)
(x2,y2,1)...

-Bc