A3 P1

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Dragon
Mausschubser
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Wohnort: Darmstadt

A3 P1

Beitrag von Dragon » 13. Dez 2008 15:06

I have implemented the mrf log prior with Matrix operations and I get as result for big images always result -inf because so many multiplications of small values are round to 0.0000 in MATLAB.
How can I avoid this?

C.
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Re: A3 P1

Beitrag von C. » 13. Dez 2008 17:06

What multiplications do you mean? There shouldn't be any multiplications (but the ones in the log studentt) to compute the log prior.
I think you take the log of the prior after you've evaluated formular (1). Think about the 'log' again, it turns a product of elements to a ......, and how you could change formular (1) with this rule.
One reason to use the log of the prior is to get rid of the numerical issues you mentioned.

Dragon
Mausschubser
Mausschubser
Beiträge: 80
Registriert: 18. Apr 2006 15:36
Wohnort: Darmstadt

Re: A3 P1

Beitrag von Dragon » 13. Dez 2008 17:35

thank you for your help. Know I think it works finde :D

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