[R] Reading a TIFF file

Uwe Ligges ligges at statistik.tu-dortmund.de
Fri Apr 22 12:37:18 CEST 2011

Unless you can provide a small reproducible example (say a very small 
tiff including the values you got from the non-R software) it will be 
hard to tell what is going on.

Uwe Ligges

On 22.04.2011 11:23, Julio Rojas wrote:
> Dear all, I have been trying to speed up a process we have been done in ArcGIS. We have to read a single layer TIFF (monochrome image) in . For this, I have used the "rtiff" package. After reading the TIFF file, I compared the raw values for each pixel that I have in ArcGIS to the ones obtained in R. In ArcGIS I have discrete values in the range 0..255, while in R I have continuous values between 0..1. This, in itself might not be a problem if the values obtained in R, times 255 would show the values obtained in ArcGIS, but this is not the case. The images are very different. I tried to settle matters using Photoshop, and the values there are completely different from the other two (using RGB, the K value (in CMYK) or the B value (in HSB))!!!
> Can somebody help me with this problem? Can I trust "rtiff"? Should I stick to a very slow process in ArcGIS? Why PS, which should be the perfect measuring stick, is showing another set of values?
> Thanks in advance. Regards.
> Julio
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

More information about the R-help mailing list