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From: Bc on 9 Feb 2010 15:31
"John D'Errico" <woodchips(a)rochester.rr.com> wrote in message <gssi41$igm$1(a)fred.mathworks.com>...
> hajoura <fradi.hajer(a)gmail.com> wrote in message <83b5d771-5ab9-45fd-9cb1-4efe819ea633(a)k2g2000yql.googlegroups.com>...
> > Thank u,
> > yes , i know that they used delaunay not delaunay3, but this paper
> > contain a lot of mistakes.
>
> Unfortunate that my French is so poor.
>
> > for example , they use delaunay and with 3 parametrs X,Y, IT. so, it
> > 's so clear it is false,
> > that's why, i think that the command is delaunay3.
>
> It is definitely not appropriate to use delaunay3 here.
>
>
> > Ok, let's forget this paper, u said that we can interpolate within
> > that triangulation.; ok,
> > i have two low resolution images about the same scene and i want to
> > interpolate them
> > using the triangulation of delaunay ;how can i do that?
>
> Sorry. I was wrong to say tsearch. You would use
> tsearchn.
>
> You have two images, offset from each other.
>
> 1. Combine the two sets of pixel coordinates,
> each built using meshgrid.
>
> 2. Use delaunay to build a triangulation of the
> combined image space.
>
> 3. Use tsearchn to give the index of the triangle
> in the triangulation that contains a given point.
> tsearchn also returns a set of barycentric weights
> or coordinates for that point within the triangle.
> Apply those weights to the image values at the
> vertices of the indicated triangle.
>
> For a random example, since I don't have an image...
>
> x = rand(100,1);
> y = rand(100,1);
> z = exp(x+y);
> tri = delaunay(x,y);
>
> Now, interpolate the resulting surface at some
> candidate point. For example, (0.5, 0.5).
>
> [T,P] = tsearchn([x,y],tri,[0.5 0.5])
> T =
> 188
> P =
> 0.62224 0.0048745 0.37289
>
> The point lies in triangle 188.
>
> zpred = z(tri(T,1))*P(1);
> for i = 2:3
> zpred = zpred + z(tri(T,i))*P(i);
> end
>
> Our prediction is
>
> zpred =
> 2.7243
>
> How well did we do?
>
> exp(0.5 + 0.5)
> ans =
> 2.7183
>
> John
=======================================
Hi everyone,

So I was reading your comments and I wanted to ask elaboration on this topic. I have also image matrices I would like to combine, so I have been trying to figure out how to do this. I tried putting them together by putting one column on one matrix followed by the corresponding column of the other matrix, but this cause my result to be larger ont he horizontal only.

For example, I image that there must be a way to combine 4 images that are of some size(4x4) into one large one that is 16x16, right? What methods are there to do this? Any functions?
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