How to determine the radial porosity distribution in the particle image?

Dear all,

I would like to determin the radial porosity distribution of these particles,

Could u give me some ideas how to determine it?

Thanks so much for your help.

JL

Answer 1

[Image Analyst]

Radial of the whole circle, or of each particle inside it?

See attached demo.

[Jialin Men]

Hallo Image Analyst,

Thanks so much for your help.

I want to know the each particle this emage.

Thanks in advance

JL

[Image Analyst]

The particles are not even circular so the radial distribution would not make any sense. Moreover, the particles are uniform intensity inside, except for a bit of noise, so the radial profile would be essentially flat. You'd have to first segment each particle individually, which maybe you can do, and then do the computation I showed you. But you'd end up with an unhelpful flat profile. I don't see any point in that.

[Voss]

@Image Analyst: To try to clarify somewhat what I think the OP's intent is, "porosity" would be an estimate of the fraction of the image that is not in any particle/grain, i.e., the "void space" or "pore space" between the particles/grains.

@Jialin Men: Is that right?

[Jialin Men]

Hallo Voss,

You are right. I try some method, but it doesn't work.

Do you have ideas?

Best reagrds

Jialin

[Image Analyst]

First of all you have to segment the image and label the blobs so that each particle is it's own blob. I think you had code for doing that. Now if you take the histogram of each particle/blob, you will se a fairly narrow histogram. Most will be dark but there are a few particles that are brighter so those will have their histogram hump shifted closer to 255. But both will have a really narrow histogram. So, looking at one particular particle, how are you deciding which pixels are solid and which are void space? It's not like you have a nice bimodel histogram that you can split down the middle into clear solid and void classes. So how do you define solid and how to you define void? And is that decision different for the bright particles versus the dark particles?

[Jialin Men]

Hallo Image Analyst,

Thanks very much for your advices, you are right, with this image it is really diffcult to define the void. I think i just make a radial distribution of particles.