FFT of an image

Hello
I have an image of size M X N (pixel).
Fisrt of all i have read the image from the path location. Then I used Unflatten Pixmap VI to convert the image to array. Now i need to find the 2 D FFT. I have to do the FFT by fist computing the transforms of the rows in parallel and then the transforms of the columns of the result. For that i extracted the N Resolution value and gave it to ta for loop ( since there are N rows for the image.) Then I calculated the FFT for these rows. The resulting array is transposed to do the FFT for the columns. Is the VI i made correct? Please see the attchement for the image.
How can i get the 2D- FFT plot ?
Thankss
Nghtcwrlr
********************Kudos are alwayzz Welcome !! ******************
Solved!
Go to Solution.
Attachments:
Question Ni 1.JPG ‏23 KB

Here is a simple program that performs frequency filtering of an image using the forward and reverse FFT transforms. I've saved a native 8.6 version and attempted to save an 8.0 version. I suspect the 8.0 version will not work properly because LabVIEW acted flakey when saving it out. The main VI is called "FFT madness RUN ME.vi"
Message Edited by Root Canal on 01-12-2009 12:43 PM
global variables make robots angry
Attachments:
fft madness eight point six.llb ‏249 KB
fft madness eight point oh.llb ‏250 KB
FFT madness duck.PNG ‏420 KB

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Hallo Filip,
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interferm.llb ‏182 KB
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Hi Vaeryn,
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Attachments:
1335097296331.jpg ‏59 KB

Hello aziz-be,
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Runing matlab in Labview

السلام عليكم
هل يمكن معالجة الصور عن طريق الماتلاب و اظهارها على الابفيو مثلا انا عندي الكود التالي:
% Load jpeg files
orgImage = imread('Pixel.jpg', 'jpg');
figure(1); imshow(orgImage);
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ampImage= abs(fftImage);
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"out put" ماهو
الذي ساختاره لاظهار الصور على الابفيو مع العلم ان هذا الكود شغال
على الماتلاب.
دعوة للكل للتفاعل معنا في الموضوع وشكرا.
تحياتي
Attachments:
Matlab script.jpg ‏59 KB

Another idea is to access Matlab using its external interfaces that match with LabVIEW possibilities (like ActiveX for example) [http://www.mathworks.com/access/helpdesk/help/techdoc/matlab_external/matlab_external.shtml].
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Good Luck!

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Thanks in advance.
Solved!
Go to Solution.
Attachments:
Resolution Decrease.vi ‏46 KB

Thank you for the prompt reply Daniel.
What we are attempting is a de-resolution of a hi resolution image to simulate what a 1-4 reduction in resolution using a fiber optic taper will look like to a customer without having to built a very expensive actual optical system. If it proves to be an acceptable resolution, then we can move forward. The point is we need a fiberoptic imaging system due to environmental issues prevernting having an actual camera up close to the work being inspected.
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Hello,
I am new to using LabVIEW so please bear with me!
I am reading/working my way through the IMAQ user manual for LabVIEW and I am trying to get IMAQ FFT working. But I have trouble finding the VI that the destination image of IMAQ FFT VI should be connected to. At the second it gives me an error when I try and run the program.
At the second I am really struggling to find the correct VI
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Hi,
For IMAQ FFT Destination Image should be connected and must be complex:
Andrey.
PS
Forum for Vision-related questions here
Message Edited by Andrey Dmitriev on 01-28-2009 12:52 PM
Attachments:
FFT Sample.png ‏24 KB
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I need use the line data(basler spl2048 camera,NI1433 board) to perform FFT transform ,how can i use transformed data to construct an image

hello everyone! as what i haved mentioned in the title.In optical coherence tomography system ,i need to perform for every line data whick accquired by NI1433,how can i use
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This is no longer my main area of expertise, but here is results of brief search:
Spectral Domain Optical Coherence Tomography System Design: sensitivity fall-off and processing speed enhancement
look at Chapter 5
https://circle.ubc.ca/bitstream/id/91474/ubc_2010_fall_chan_kenny.pdf
Ultrahigh-resolution, high-speed, Fourier
domain optical coherence tomography and
methods for dispersion compensation
http://www.opticsinfobase.org/oe/abstract.cfm?uri=OE-12-11-2404
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Attachments:
GrabWhileLoop.png ‏34 KB
MainWhileLoop.png ‏68 KB

Thanks for the comment. I have looked into the producer/consumer architecture, but to be honest, I'm not quite sure how everything will work while doing that. I have seen the example codes, and I have thought about implementing (or at least attempting to) but I'm still unconvinced that it will run that much more efficiently. There is other setup outside of the images that had to be done outside of either while loop. Also, I don't know where I would put both loops.
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IMAQ FFT multiplication and MATLAB Script Nodes/Compact Rio

I would like to automatically generate a frequency kernel to multiply with the FFT of my IMAQ image. I was wondering if there was a way for LabVIEW to automatically set up 2D arrays (with a lower bound, a step size and a higher bound) like what is done in MATLAB.
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may the G be with you ....

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Attachments:
phase fft.vi ‏153 KB

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