[R-sig-Geo] raster or rgdal: problem with geometry of tif + tifw file

[Agustin Lobo]

Hi!

I read a tif fle (with a companion tifw file) for which gdalinfo states:

alobo at alobo-laptop:/media/TRANSCEND2/VegcamPro/MATA20090729/Proc2$
gdalinfo SDIM0114.tif
Warning 1: TIFFReadDirectory:Unknown field with tag 37717 (0x9355) encountered
Driver: GTiff/GeoTIFF
Files: SDIM0114.tif
Size is 2640, 1760
Coordinate System is `'
GeoTransform =
  445548.7745816645, -0.109570548549058, 0.216912817625298
  4628418.279379116, 0.216912817625298, 0.109570548549058
Metadata:
  TIFFTAG_SOFTWARE=SIGMA Photo Pro 3.5.2.0000
  TIFFTAG_DATETIME=2010:02:27 15:40:55
  TIFFTAG_XRESOLUTION=180
  TIFFTAG_YRESOLUTION=180
  TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)
Image Structure Metadata:
  INTERLEAVE=PIXEL
Corner Coordinates:
Upper Left  (  445548.775, 4628418.279)
Lower Left  (  445930.541, 4628611.124)
Upper Right (  445259.508, 4628990.929)
Lower Right (  445641.275, 4629183.773)
Center      (  445595.025, 4628801.026)


Then I read it in R:
> test= brick("/media/TRANSCEND2/VegcamPro/MATA20090729/TIFFOri/SDIM0114.tif")
> show(test)
class       : RasterBrick
dimensions  : 1760, 2640, 3  (nrow, ncol, nlayers)
resolution  : 0.1095705, 0.1095705  (x, y)
extent      : 445548.8, 445838, 4628418, 4628611  (xmin, xmax, ymin, ymax)
projection  : NA
values      : /media/TRANSCEND2/VegcamPro/MATA20090729/TIFFOri/SDIM0114.tif
min values  : 0 0 0
max values  : 65535 65535 65535

and write it back to disk:

> writeRaster(test,file="test.tif", format="GTiff", overwrite=TRUE,datatype='FLT8S')

But gdalinfo states a different bounding box for the new file:
alobo at alobo-laptop:/media/TRANSCEND2/VegcamPro/MATA20090729/Proc2$
gdalinfo test.tif
Driver: GTiff/GeoTIFF
Files: test.tif
Size is 2640, 1760
Coordinate System is `'
Origin = (445548.774581664009020,4628611.233115110546350)
Pixel Size = (0.109570548549241,-0.109570548548469)
Image Structure Metadata:
  COMPRESSION=LZW
  INTERLEAVE=PIXEL
Corner Coordinates:
Upper Left  (  445548.775, 4628611.233)
Lower Left  (  445548.775, 4628418.389)
Upper Right (  445838.041, 4628611.233)
Lower Right (  445838.041, 4628418.389)
Center      (  445693.408, 4628514.811)
.../...

Somehow the geometric properties are modified in R

I've made a single geotif file with gdal_transform (no tifw created)
and read it in R in the same way and get the same result, so the
problem does not come
from using a tifw file as I initially thought.

Perhaps a bug in brick() ?

Thanks

Agus

Files:
http://dl.dropbox.com/u/3180464/SDIM0114.tif
http://dl.dropbox.com/u/3180464/SDIM0114.tifw

> sessionInfo()
R version 2.13.0 (2011-04-13)
Platform: i486-pc-linux-gnu (32-bit)

locale:
 [1] LC_CTYPE=en_US.UTF-8          LC_NUMERIC=C
LC_TIME=en_US.UTF-8
 [4] LC_COLLATE=en_US.UTF-8        LC_MONETARY=en_US.UTF-8
LC_MESSAGES=en_US.UTF-8
 [7] LC_PAPER=en_US.UTF-8          LC_NAME=en_US.UTF-8
LC_ADDRESS=en_US.UTF-8
[10] LC_TELEPHONE=en_US.UTF-8      LC_MEASUREMENT=en_US.UTF-8
LC_IDENTIFICATION=en_US.UTF-8

attached base packages:
[1] grid      stats     graphics  grDevices utils     datasets
methods   base

other attached packages:
[1] gridExtra_0.7 ggplot2_0.8.8 rgdal_0.6-31  raster_1.8-15 sp_0.9-72
   reshape_0.8.3
[7] plyr_1.2.1    proto_0.3-8   rkward_0.5.6

loaded via a namespace (and not attached):
[1] lattice_0.19-26 tools_2.13.0