On Mon, 21 Nov 2005, Sydler, Dominik wrote: > Hi there > > I'm looking for a function to read PNG-bitmap-images from a file into R. > I only found: > - the pixmap-package which cannot import png or similar formats > - the rimage-package which can only import lossy jpeg-images (the > convertion from png to jpeg modifies the data!) > > Is there any possibility to read PNG-files?
Under Linux, install GDAL directly then package rgdal from source, I guess some variant of this under OSX. Under Windows, install the rgdal binary package from Prof. Ripley's repository - for me: > options("repos") $repos CRAN CRANextra "@CRAN@" "http://www.stats.ox.ac.uk/pub/RWin" or download from: http://www.stats.ox.ac.uk/pub/RWin/bin/windows/contrib/2.2/ directly. Then: > x.png <- GDAL.open(file.choose()) > getDriverLongName(getDriver(x.png)) [1] "Portable Network Graphics" >From there you use getRasterData() on the bands and subscenes you want, GDAL.open() just returns a file handle, letting you choose the parts you need. That is probably the least resistance path. > > Thanks for any help > Dominic Sydler > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > -- 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] ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html