2D fourier transform of interferometric images

Hello Everyone

I have a stack of images from my white light interferometer to measure the surface topography and the first image is the xz cross section of image where z represents the vertical direction. Now when I perform the 2D fft of this first image, I get the 2nd image and 3rd image image is just the colored version of it , but as it can be seen that the fft is has lot of artifacts , so can anyone provide me some suggestion as I read from post that windowing can be done , please help and I don’t have much experience in image processing

The first image is real image with same pixel size as taken by camera but other images i just saved and pixel size may be rescaled.

I can only upload one image so i will upload fft imges in comment

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color2dfft

Hi @Ankit_singh_rawat,

I’m less accustomed to looking at this type of image, so just to confirm, this is an axial cross section of a stack of images right? What are those faint darker vertical lines where the interference fringes break? (I’m mostly curious if that’s some sort of stitching artifact, or if that’s in the raw data)

Is the core question here, “how do i perform windowing before taking an FFT”? If so, please let me know what software you’re using (e.g. python, imagej, matlab, etc…)

Hi Talley

Thanks for your response.

Actually this is the interferometric fringe pattern for a step height structure as this is a fringe pattern for surface profiling of step height structure and yes this is the axial cross section of stack of images.

I am using MATLAB for this.

Hi @talley

I have attached an image and I want to perform these steps with my image.

I have attached another image in next reply which is the final result of these 5 steps

THis is the final 2DFFT after performing above steps
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