Sentinel 1 HH Pol Required

good idea :slight_smile:
And good luck with your study

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Hi @ABraun,
I performed the HAalpha decomposition on sentinel 1 img. When I shared the results with my supervisor he replied this is wrong. How come two 2x2 matrix C11 and C22 return Entropy Anisotropy and Alpha. It should’ve Entropy and Alpha Only. My question is wether something is wrong with SNAP or what the three bands comprehend here?

I’m not sure how anisotropy is calculated in the dual-pol operator, but you find the source code here: https://github.com/senbox-org/s1tbx/blob/master/rstb/rstb-op-polarimetric-tools/src/main/java/org/csa/rstb/polarimetric/gpf/decompositions/HAlphaC2.java

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I think I need a developer

@ABraun check this out. SNAP doesn’t have the Claude-Potteir Dual Pol as you suggested and the HAlpha Dual pol returns three bands. I am on latest version of SNAP all plugins updated.

Screen Shot 2021-03-26 at 6.04.30 AM|690x431

you are right - it must have gone since the last update. I don’t see it any longer.

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Should I downgrade? Or wait for the new update? Maybe that’ll have the fix for dual pol H-Alhpa decomposition. I hope. What do you think?

How much time will it take for the new updates and the fixes for these minor issues?

I am not sure there is an issue - did you read the corresponding help?

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I don’t know - the Claude Pottier Dual Pol Decomposition was there 5 days ago.
@jun_lu Has this operator been changed with a last update?

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Mine shows three bands for HAlhpa decomposition (Entropy Anisotropy and Alpha), and Cloude Pottier dual pol decomposition is not available at all. As @ABraun ascertained three threads above.

A post was split to a new topic: Problem installing sen-et

I think H-Alpha decomposition is the only available dual-pol decomposition. However, there is a “Cloude-Pottier” classification for dual-pol product

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Cloude Potteir is not available in the new update and HAlpha dual pol returns three bands “Entropy Anisotropy and Alpha”

There is no Cloud Potteir decomposition for dual-pol product. The H-Alpha decomposition for dual-pol used to return just two bands. The third band (alpha band) was added on users’ request. Basically it mimic the alpha computation for quad-pol case. You can ignore it

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Wow, never knew it. Haha

Thank you so much :blush:

Although there’s an option available “Cloude - Pottier Dual Pol”

BTW is that alpha or Anisotropy you’re talking about? H α has “alpha” not Anisotropy.

I also wonder what it is:

grafik

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Hmm PolSAR pro then :thinking:

I don’t know how many dual polarization tools it offers

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