I'm using GRASS to perform an unsupervised classification on a time series of LANDSAT images (monthly temporal res, over 30 years), in order to compare land cover change in a particular area.
I'm concerned that if I run
i.cluster for each map in the time series the signatures used for the classes may be slightly different for each map, affecting the validity of the comparison. Would this be the case? If so, is there a way to ensure that the class signatures used on each map in the time series are identical throughout?
My initial idea was to run
i.cluster on a particular map where all classes are well represented, then use the sigfile generated from this as the input sigfile to
i.maxlik for all maps.