Locating peaks on complex image

I would like to read, process and analyse complex images:

The first task I have is to locate 'maxima' and 'minima' on these images. By minima I mean dark spots in light background and by maxima I mean the opposite.

Any help is appreciated,

Thank you

Arthur

[KSSV]

Attach one image..so that we can help you. YOu need to read image using imread and then check for pixel values.

[Arthur Moya]

KSSV thank you for the quick response. The Imread command cannot read complex images. I cannot seem to attach the image in its 'true' format which is a complex image in the Digital Micrograph 3 format (.dm3). It is a file extension common for electron microscopy data acquired using Gatan software. I converted it into a png format for you to have an idea of what I am looking at, if that would be useful. Or I can just email you the file. Ps- I have tried using a matlab extension for reading DM3 files (by Dr Fred Sigworth) and it still cannot read complex images.

[Sushant Mahajan]

What do you mean when you say 'maxima' or 'minima'? Is it the maxima/minima of the absolute value (sqrt(real^2+imaginary^2))? Or the maxima/minima of either the real or imaginary components?

[Image Analyst]

"I converted it into a png format for you" <= OK fine, but why didn't you attach it? You might be able to use a bottom hat filter, or maybe just simple thresholding if the image is simple enough..

[Arthur Moya]

Dear @Sushant Mahajan I am looking for the minima and maxima of the imaginary component of the image. @Image Analyst, here is the image. Thank you for your responses,

I truly appreciate your input,

Arthur Moya

[Guillaume]

It seems to me that if you want to process your raw image with matlab, before thinking of that min/max algorithm you first need to solve the import problem since you say that the current import function that you tried does not work with your images.

Unless you're happy to work with your images converted to png of course.

Note that matlab has no concept of a complex image, so to use the image processing toolbox functions you'll have to split to convert your complex numbers to real numbers at some point (or work on imaginary and real part separately).