My machine currently has 4 GB on it, but a lot of that's getting eaten by video memory and the other programs I have in memory. Also, some of my image cubes are 12 GB in size, so I'd need to find a workaround anyways. However, since what my colleagues and I are interested in are pixel-by-pixel spectral analyses, I assume the best approach would be to pass the spectra either from ENVI/IDL (for which there is no frontend, but I have logged a request with ITT Visual Solutions to develop one) or conversely from ArcGIS (which can read ENVI data with the ENVI Reader) into R for analysis.
Are you aware of ways to send arrays back and forth between R and ArcGIS? Guy On Tue, Jul 29, 2008 at 4:24 PM, Roger Bivand <[EMAIL PROTECTED]> wrote: > On Tue, 29 Jul 2008, Guy Serbin wrote: > >> Thank you all for the help- I successfully read an image into R using >> these methods. >> >> I did, however, encounter some problems when loading a hyperspectral >> image cube into R as it was unable to allocate the 2.9 GB of volatile >> memory that it needed. > > Buy more memory, 64-bit Linux works fine. Seriously, R is for statistics, so > its memory management is designed for samples, even though very large > samples can be handled when used appropriately. If your data are in a > GeoTiff, you can read them by band using functions in the rgdal package, or > equally well many bands in a window or tile of a larger scene. Note that > ArcGIS uses GDAL too for handling some raster formats. Using R does mean > thinking through your work flow. > > Roger > >> >> Is there a way to improve memory management by R, so that it only >> reads in the data when actually needed for processing, e.g., only read >> in the bands I need, or conversely read in spectra on a per-pixel >> basis? >> >> Guy >> >> On Tue, Jul 29, 2008 at 4:05 PM, PUJAN RAJ REGMI >> <[EMAIL PROTECTED]> wrote: >>> >>> This might help to mange the orientation of image: >>> >>> # To read ENVI format >>> cir.image<-("YOUR_ENVI_FILE") >>> CIR.envi<-read.ENVI(cir.image,headerfile=paste(cir.image,".hdr",sep="")) >>> # To Show image >>> CIR.envi.band1<-CIR.envi[,,1] >>> CIR.envi.band1.s<-CIR.envi.band1[order(nrow(CIR.envi.band1):1),] >>> CIR.envi.band1.t<-t(CIR.envi.band1.s) >>> image(CIR.envi.band1.t,main="") >>> mtext("Raw Matrix ENVI Image for Band1", side=3,line=2, font=3,cex=1.25) >>> >>> Pujan >>> ________________________________ >>>> >>>> From: [EMAIL PROTECTED] >>>> To: [EMAIL PROTECTED]; R-sig-Geo@stat.math.ethz.ch >>>> Date: Tue, 29 Jul 2008 14:24:04 -0400 >>>> Subject: Re: [R-sig-Geo] ENVI data and R >>>> >>>> This code might help: >>>> >>>> >>>> >>>> ############################################################################ >>>> #### >>>> >>>> >>>> ############################################################################ >>>> #### >>>> ## Read in envi file >>>> cir.image <- "C:/YOUR_ENVI_FILE" >>>> CIR.envi = read.ENVI(cir.image, headerfile=paste(cir.image,".hdr", >>>> sep="")) >>>> >>>> >>>> >>>> ############################################################################ >>>> #### >>>> >>>> >>>> ############################################################################ >>>> #### >>>> ## Show image >>>> CIR.envi.band1 <- CIR.envi[,,1] >>>> image(CIR.envi.band1, main="") >>>> mtext("Raw Matrix ENVI Image for Band 1", side=3,line = 2, font=3, >>>> cex=1.25) >>>> >>>> >>>> >>>> ############################################################################ >>>> #### >>>> >>>> >>>> ############################################################################ >>>> #### >>>> >>>> Andrew Niccolai >>>> Doctoral Candidate >>>> Yale School of Forestry >>>> >>>> >>>> >>>> -----Original Message----- >>>> From: [EMAIL PROTECTED] >>>> [mailto:[EMAIL PROTECTED] On Behalf Of Guy Serbin >>>> Sent: Tuesday, July 29, 2008 12:55 PM >>>> To: R-sig-Geo@stat.math.ethz.ch >>>> Subject: [R-sig-Geo] ENVI data and R >>>> >>>> Hi, >>>> >>>> I was wondering if anyone knows how to either call up R functions from >>>> within IDL, or conversely read ENVI image data into R. If you have >>>> any advice I'd greatly appreciate it. >>>> >>>> Thanks, >>>> Guy Serbin >>>> >>>> -- >>>> Guy Serbin, Ph.D. >>>> Research Soil Scientist >>>> Hydrology and Remote Sensing Lab >>>> Bldg 007 Rm 104 BARC-West >>>> 10300 Baltimore Blvd >>>> Beltsville, MD 20705-2350 USA >>>> +1(301)504-5250 [EMAIL PROTECTED] >>>> >>>> _______________________________________________ >>>> R-sig-Geo mailing list >>>> R-sig-Geo@stat.math.ethz.ch >>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo >>>> >>>> _______________________________________________ >>>> R-sig-Geo mailing list >>>> R-sig-Geo@stat.math.ethz.ch >>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo >>> >>> ________________________________ >>> Stay in touch when you're away with Windows Live Messenger. IM anytime >>> you're online. >> >> >> >> > > -- > Roger Bivand > Economic Geography Section, Department of Economics, Norwegian School of > Economics and Business Administration, Helleveien 30, N-5045 Bergen, > Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 > e-mail: [EMAIL PROTECTED] > > -- Guy Serbin, Ph.D. Research Soil Scientist Hydrology and Remote Sensing Lab Bldg 007 Rm 104 BARC-West 10300 Baltimore Blvd Beltsville, MD 20705-2350 USA +1(301)504-5250 [EMAIL PROTECTED] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@stat.math.ethz.ch https://stat.ethz.ch/mailman/listinfo/r-sig-geo