What is the number of slip bands within a grain about defdap HOT 14 CLOSED

I think an idea for counting slip traces that shouldn't be too hard to implement would be:

• Find the slip band angle with the radon transform and peak utils as normal
• Take a line profile of strain perpendicular to this direction, see attached image. Knowing where to place the line automatically could be tricky though, maybe just through the centre of the grain would do.
• Count the peaks in this profile. The peaks should be easier for peak utils to spot in your high resolution maps too.

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Good idea with the line scan, I could easily implement this. It might be tricky for oddly-shaped grains as we wouldn't be able to get a single linescan to all corners.. and there could be issues in grains with multiple slip systems.

I will look into the Hough transform Joao, but my limited understanding of it is that it results in something very similar to the radon transform

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I'm just going to try the Hough transform now on a very simplified image. I'm not sure it will pick out similar repeated features but I want to see

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Hough transform is definitely a possibility.
I just used this: http://scikit-image.org/docs/dev/auto_examples/edges/plot_line_hough_transform.html

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Ok looks promising! Thanks for looking into it. In applying this on a grain basis we would have to make sure that the edge or boundary of the grain is not included in the calculation - I assume that the radon transform function we have does this already

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No the current radon function uses the whole grain but applying binary erosion to the outline of the grain should remove a pixel from the boundary. Then use that as a mask for the grain image

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I have got this working to some extent; I can detect some bands but not them all. As @JQFonseca suggested, filtering is required but I found that the FFT filter is selective in sharpness and what I need is filtering based on strain value - this highlights the bands better.

The images below show with and without a minimum limit on the strain value in the input image. The example is made by slicing the data so as to look in the grain centre - I have not been able to degrade the boundaries as @mikesmic suggested. Michael, can you point me towards where the radon transform does this so that I might imitate it? I couldn't find it in the hrdic grain class.

You'll notice that I'm still not getting all of the bands, not sure why at the moment

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Looks good. Could you create a new branch and I'll try and add to what you have done?

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I have created a branch from the master and then committed a change to hrdic.py. I have not used GitHub like this before so I'd appreciate feedback as to whether that's the right thing to do! Thanks

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I have now added a notebook for the Hough transform work in my repository. There is example ebsd data in example_data_AH but the hrdic data was too large for the repository (85 MB and the limit is 25MB). I have added a dropbox link to the hrdic data in the notebook. It will need to be downloaded and moved into the example_data_AH directory.

I tried using Michael's example_data but the Hough transform didn't seem to work as well - the slip traces in gamma prime strengthened alloys are much sharper.

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