functions with multiband raster datasets

Discussion created by gatewing on May 8, 2014
Latest reply on May 14, 2014 by gatewing

I have loaded several tiff files containing R, G and B bands. My first action was to resample these raster datasets, which resulted correctly in resampled raster datasets, each still containing R, G and B bands. Based on these multiband raster datasets, I now want to do some math functions, but it seems that these are performed on only one of the raster bands, and result in a single band raster. For instance, when I use Minus or Divide on two of these multiband raster datasets, I get a single band raster in return, whereas I would expect a resulting multiband raster where R(result) = R(1) / R(2), G(result) = G(1) / (G2) etc. More specifically, it seems that only the red bands (listed first) are considered and make up the resulting single band. The same goes for local statistics (for instance when calculating the mean of two multiband raster datasets).

- how can I perform spatial analyst functions on the multiband raster datasets and get multiband rasters as outcome, with the functions applied to each of the corresponding bands?
- alternatively, I could first split all the raster datasets into multiple single band rasters and work from there with the spatial analyst functions. But how do I split these bands or how do I batch load the individual bands of my original RGB tiffs?

Thanks for any help