Change the number of bins in Radon transform

Dear experts,

Is there any way to change the defaut munber of bins in matlab built in Radon transform? I want to perform a Radon transform on an image with a specific number of bin (stand for the munber of detectors), and a specific bin width.

thank you.

Answer 1

[Walter Roberson]

% Grandfathered syntax
%   R = RADON(I,THETA,N) returns a Radon transform with the
%   projection computed at N points. R has N rows. If you do not
%   specify N, the number of points the projection is computed at
%   is:
%
%        2*ceil(norm(size(I)-floor((size(I)-1)/2)-1))+3
%
%   This number is sufficient to compute the projection at unit
%   intervals, even along the diagonal.

[Hieu Phan]

Thank you,i totaly missed it.But what about the bin's space? Can somehow modify that too?

[Walter Roberson]

radon() does not give any control for that.

[Hieu Phan]

If there is an agorithim alow control that variable, would that come into any practice?

[Walter Roberson]

I do not know.

When you use a fixed bin size, then you are not using a constant angle: you are using a larger angle when you are closer to the origin and a smaller angle further from the origin. That changes the mathematics of the transform, and the usual calculations do not apply.