Performing change analysis between two time series images (2010-2000)

Question

I performed the difference between two images, 2010-2000, with the command in Arcmap10: Image Analysis and raster difference,based on the pixel value difference in the two image tables (2010, 2000). The pixel value in each image represents the land cover aggregated class, with 6 class at all, and I need to represent the change value in the table of the output image as a combination of the single values in the two original images, ex: image 2000 pixel value=1; image 2010 pixel value=3, the pixel value of the output image should be: value= 13, which means that the land cover classes changed from 1 in 2000 to 3 in 2010.

How can I remap the pixel value in the output table like that?

Answer 1

If you need to deal with NoData pixels you could use the Raster Calculator Tool and enter the following expression :

Con(IsNull("Raster2000"),0,"Raster2000" * 10) +  
Con(IsNull("Raster2010"),0,"Raster2010")

That would create an output of all possible land use change combinations including the pixels that changed from NoData to a land use and vice versa.