I'm applying between QGIS and GRASS to apply a semi-automatic classification of aerial photos. In practice I would like to use the combination of the grass modules in the processing of QGIS; i.cluster and i.maxlink. My problem is that with i.cluster I can not create the "spectral signature" which then must be used in the second module. Why? In practice I use two photo areas and I left (As proof) the preset parameters but at the end of the process (Although it does not give me errors), only a final report is created and no spectral signature files. Why?