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11-20-2012 11:23 PM

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I have an array of size 600 by 600 pixels. In a circle of given radius (say 50 pixels) and given origin (given ith row and jth column), I want to plot gaussian distribution, i.e., give the pixels

the value of a 2-D gaussian distribution with peak at the origin. How do I do this in labview ?

Thanks.

Solved! Go to Solution.

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Solution

Accepted by Alice12

11-21-2012 12:57 AM

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You would run your x and y values through the 2D Gaussian function but making the origin 300,300 (for your given 600x600 pixel array). Here's what I get on an intensity chart given an amplitude of 10 and sigma = 100 pixels:

Here's the example (quick and dirty) code:

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11-21-2012 07:35 AM - edited 11-21-2012 07:48 AM

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--

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11-21-2012 07:48 AM - edited 11-21-2012 07:53 AM

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Thanks for your reply.

How do I convert this intensity distribution into a greyscale (uint8) image (a matrix with all elements between 0 and 255) ?

I used "To Unsigned Byte Integer" function but it doesn't seem to solve the problem ?

11-21-2012 02:09 PM

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11-22-2012 12:27 AM

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I tried to follow your hints but didn't succeed. May be I'm missing something silly.

Attached is my program. Please change it to obtain the desired pattern.

Thanks.

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11-22-2012 12:57 AM

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You used the wrong exponential...Use "exp(x)" instead of "exp(x) - 1".

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11-22-2012 01:07 AM

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Thank you for pointing out the mistake.

It works.

Regards.

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11-22-2012 01:08 AM - edited 11-22-2012 01:39 AM

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Here's a one-loop version. It is sufficient to calculate a singe 1D gaussan once, then use the outer product to generate the 2D array.

This means we only need to evaluate only 600 exponential functions instead of 360000! 😄 (You could reduce it again by 50% taking advantage of symmetry. Try it!)

(see also)

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11-22-2012 02:18 AM

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Thanks.

It's definitely a better approach.

Regards.