[Inquery] Change distance in Haralick features

[glemaitre]

Hi,

I am currently working with Haralick features and wanted to have a discussion about that. Sometimes, it could be handy to play with a distance parameter when computing the co-occurence instead of using the default value (1 px).

I was checking what could be the best way to modify the source and thought that it could be easier to discuss here. I see two possibilities:

• Modifying the distance for the variable _2d_deltas and _3d_deltas with an initialisation. However, I do not have a clear idea of the consequences (I did not go into detail in the C file which allow to compute the GLCM)
• Resample the input image. But again, I am not really sure of the consistency.

  Cheers,

Guillaume Lemaitre

[luispedro]

The resampling is the easiest and can be done with the existing code, but it is not the exact same result.

You don't need to change the C code, you just need to pass it a correct "neighborhood", for example for D=2, direction "right", instead of

[[0 0 0]
 [0 0 1]
 [0 0 0]]

you need to pass it:

[[0 0 0 0]
 [0 0 0 1]
 [0 0 0 0]]

HTH Luis

[glemaitre]

thanks

[luispedro]

Actually, that probably should be:

[[0 0 0 0 0]
 [0 0 0 0 1]
 [0 0 0 0 0]]

(ie, a 5x5 matrix).

[glemaitre]

Ok if I come to do it, I would make a pull request if you are interested.

[luispedro]

Thanks. I would certainly be happy to see this feature (I use the downsampling method myself, but others have asked about it).