Changes in pixel values and colours after resample+subset

s2tbx
#1

Hi there,
I have been resampling and subsetting a load of S2 imagery to convert them to geotiff to import into ENVI through the batch processing operation. However, my resampled and subset imagery looks markedly different to the 2A product and the pixel values are very different. I was wondering if I have missed a key step somewhere. I pulled together a graph first with read, resample (to 10m using B2 as a reference band) and then subset using a WKT in the geographic coordinates and then write the end product as a geotiff. I then used this graph as the basis for my batch processing. Should I have saved a s beam-dimap and then exported this out as a geotiff?

Any help much appreciated.

cheers
Liz

#2

Hi Liz,

by different pixel values you mean they differ by a factor of 10000?
That’s because in GeoTiff the raw values are stored. The scaling factor is not applied.
If you want to use ENVI, it would be the easiest way to save to BEAM-DIMAP and use the files from the *.data directory.
You can also use the band math or convert band.
See this thread: Exporting OLCI WFR TSM as GeoTIFF