how to find impulse location of an image?

the image can be cosine function, after taking dft we will get impulse at some points, here i need to find the position of impulse. pls help me

Answer 1

[Image Analyst]

How about thresholding followed by regionprops() to ask for the centroid?

binaryImage = real(fftImage) > threshold;
labeledImage = bwlabel(binaryImage);
measurements = regionprops(labeledImage, 'Centroid');

How about imregionalmax() followed by regionprops() to ask for the centroid?

binaryImage = imregionalmax(real(fftImage));
labeledImage = bwlabel(binaryImage);
measurements = regionprops(labeledImage, 'Centroid');

You forgot to post your image by the way.