Hi Eric,

I did not look in detail to the implementation but I know that textures
computation in this filter is mostly based on the implementation
available in ITK class HistogramToTextureFeaturesFilter:

http://www.itk.org/Doxygen/html/classitk_1_1Statistics_1_1HistogramToTextureFeaturesFilter.html

Please let us know if you find something wrong between formulas provided
in ITK and OTB dowygen documentation and references and the current
implementation

Note also that there is a test in OTB which create "by hand" a
co-occurence matrix and compute texture features (could help to
investigate possible problems):

http://hg.orfeo-toolbox.org/OTB/file/b7cbca69fc3d/Testing/Code/FeatureExtraction/otbGreyLevelCooccurrenceMatrixAdvancedTextureCoefficientsCalculator.cxx

Regards,

Manuel

Le 22/09/2014 14:53, Erik a écrit :
> Hello Everybody!
>
> i have a question concerning the derivation of Haralick features
> implemented in the 
> |
>
>
>       otb::ScalarImageToTexturesFilter
>
> |
> class:
>
> Perhaps i am missing something but i do not understand why a different
> mean value is used for the Haralicks Correlation feature and the rest
> of the features. Following this i do not get what the 
> |
> marginalSum
> |
> variable represents and why it is used to calculate the mean and
> deviation for the Haralick Correlation feature.
> I am referring to the file /otbHaralickTexturesImageFunction.txx/
> (doc: 
> http://orfeo-toolbox.org/doxygen/otbHaralickTexturesImageFunction_8txx_source.html)
>
> Below is the part of the code my question is related to
> |
> while(it !=glcVector.end())
> {
> doublefrequency =(*it).second /totalFrequency;
> CooccurrenceIndexType
> <http://orfeo-toolbox.org/doxygen/classitk_1_1Index.html>index
> =(*it).first;
> pixelMean +=index[0]*frequency;
> marginalSums[index[0]]+=frequency;
> ++it;
> }
> --------------------------------------------------
> textures[7]+=index[0]*index[1]*frequency;
> textures[7]=(fabs(marginalDevSquared)>1E-8)?(textures[7]-marginalMean
> *marginalMean )/marginalDevSquared :0;
>
> |
>
> Many thanks in advance for your help!
> Greetings,
> Erik
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-- 
Manuel GRIZONNET
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31401 Toulouse Cedex 09 - France
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