How to import images to this function? need help

function sp = LoG(varargin)
%  USAGE:
% sp = LoG(<input image>, <minimum radius>, <maximal raidus> , <detection threshold>);
% Get arguments and/or default values    
[im, Rmin, Rmax, peakthr] = checkargs(varargin(:)); 

if size(im,3) >1
    img = rgb2gray(im);
else
    img = im;
end

img = double(img);

block = [];
for s = Rmin:Rmax
    h = -(s^2) * fspecial('log',s*5,s); % minus just so max is what we want
    result = imfilter(img,h,'replicate');
    
    % creates a scale space block to find location and scale of nuclei
    block = cat(3,block, result);
end

[Cxy, indx] = max(block,[],3);

G     = fspecial('gaussian', 20, 2);
Cxy_g = imfilter(Cxy, G,'symmetric');

ir_max = imregionalmax(Cxy_g);
ir_max = ir_max.*Cxy_g;
ir_med = imdilate(ir_max,strel('disk',min(Rmax,6),0));
ir_max = (ir_med == ir_max).*ir_max;

[r, c] = find(ir_max>peakthr);

sp = struct('radius',[],'x',[],'y',[],'px',[],'py',[],'resp',0);
for p = 1:length(r)
    sp(p).x = c(p);
    sp(p).y = r(p);
    sp(p).radius = indx(r(p),c(p)) + Rmin - 1;
    sp(p).resp = Cxy(r(p),c(p));
end

Answer 1

[Image Analyst]

You'd do

im = varargin{1};
minRadius = varargin{2}
maxRadius = varargin{3}

[Arshad Ali]

i am new in matlab don,t have any idea how would i do that? can you please tell me more clearly? and how i use this in the above code to import images? Thanks in advance

[Image Analyst]

function sp = LoG(varargin)
%  USAGE:
% sp = LoG(<input image>, <minimum radius>, <maximal raidus> , <detection threshold>);
% Get arguments and/or default values    
im = varargin{1};
if nargin >= 2
    % They've passed something in.
    minRadius = varargin{2}
else
    % Nothing passed in use default
    minRadius = 5;
end
if nargin >= 3
    % They've passed something in.
    maxRadius = varargin{3}
else
    % Nothing passed in use default
    maxRadius = 10;
end
if size(im,3)  > 1

etc.

[Arshad Ali]

hello sir it gives me error likr this

Index exceeds array bounds.

Error in Untitled2 (line 5)

im = varargin{1};

[Image Analyst]

Then nothing is being passed in at all, not even an image. Try this

if nargin == 0
    im = varargin{1};
else
    im = imread('cameraman.tif') % Create some default.
end

[Arshad Ali]

agian it gives me the same error

Index exceeds array bounds.

Error in Untitled2 (line 6)

im = varargin{1};

[Image Analyst]

1. What is nargin's value?
2. Attach your .m and .fig file, and
3. tell me how you're calling sp = LoG(varargin).

[Arshad Ali]

any value you can give to varargin.

i am calling function like that.

sp = LoG(5);

[Image Analyst]

OK, that answered only #3.

Why are you not answering the two others?

[Arshad Ali]

actually this code is written by other person. you can check the LoG.m files

[Walter Roberson]

You cannot call that code just passing in a single scalar value. You must pass in at least 4 values.

1. The first must be an image array -- not the name of an image, but the content of the image, such as the result of imread() of an image
2. the second must be the minimum radius to use
3. the third must be the maximum radius to use
4. the fourth must be the dection threshold

[Image Analyst]

The code I gave you (and attach here) does work if you put it in, and call the functions with the variables in the right order: image, minRadius, maRadius.

You can't just pass in 5, which is one of the radii, without passing in things that come before it also. For example if you pass in the min radius, you must pass in the image. So here are the ways you can call it

sp = LoG(grayImage) % Pass in image but no radii
sp = LoG(grayImage, 5) % Pass in image and min radius, but no max radius
sp = LoG(grayImage, 5, 10) % Pass in everything you can, in proper order.

but you cannot do this:

sp = LoG(5)  % Pass in either min or max radius with no image first.

as you did.