How to remove Poisson noise in an image? Which filter is suitable for this noise removal?

I want to remove poisson noise from an image and it is to be further enhance... So please help me to denoise the poisson noise. Please tell a suitable filter to remove the poisson noise

[gizem kalkanci]

hi have you any answer in this problem. ı have a image with poisson noise and ı couldnt found solving how to remove poisson noise from image. pls can you help me

Answer 1

[Image Analyst]

It's very rare to have Poisson noise or "shot" noise. Why do you think you have it? I have doubts. What is your imaging situation? You'd have to have extremely low light levels or be using an image intensifier. The best solution is to simply collect more light.

[Guilherme Silva]

Isn't it the noise present at low intensity images? Or low intesity patches of images, like shaded regions. "The best solution is to simply collect more light." That's not possible in my case.

[Image Analyst]

As this article says "In general, the only way to reduce the effect of photon noise is to capture more signal." If you can't do that you may be out of luck. Note that you can have a low intensity image that has noise that is NOT Poisson/shot noise. For example if you took a picture of a scene with a digital camera with just a fast exposure, it may be noisy but not photon limited. You're really only photon noise limited in the situation where you have like 1 to 20 photons per CCD well (pixel) and this occurs only in special optics or astonomical imaging situations. Just setting your DSLR to 1/2000 of a second and getting a dark noisy/grainy image does not mean that the noise is photon noise.

Discussion of photon limited images in Wikipedia: https://en.wikipedia.org/wiki/Shot_noise

You can also try this link but you may not find much help.

For a comprehensive overview of image filtering methods, see this paper https://users.soe.ucsc.edu/~milanfar/publications/journal/ModernTour.pdf by one of the premier image noise professors in the world.

You might be able to use some sort of noise removal method. It might not give you the same image that you'd get if you had 100 times more light collected, but it may give you something that you might be able to use to make whatever measurements you want, like an estimate of the area of some blob.