Bugs in Virtual Dimensionality

Summary

Correction of the Virtual Dimensionality (VD) algorithm. This fixes the bug #1841 (closed).

Rationale

In the virtual dimensionality algorithm, according to [1] (this is the reference cited in the code), the variance of the noise should be estimated as sigma = 2/N * (lambdaK^2 + lambdaR^2) instead of sigma = 2/N * (lambdaK + lambdaR + lambdaK*lambdaR). lambdaK and lambdaR being the sorted eigenvalues of the covariance and the correlation matrices, respectively.

[1] C.-I. Chang and Q. Du, "Estimation of number of spectrally distinct signal sources in hyperspectral imagery", IEEE Transactions on Geoscience and Remote Sensing, vol. 43, no. 3, mar 2004.

Additional notes

The baselines for virtual dimensionality (class and application) has been modified

Copyright

The copyright owner is CNES and has signed the ORFEO ToolBox Contributor License Agreement.

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