[Gdal-dev] transparent Geotiff?

[Bart van den Eijnden]

Hi list,

I have a lot of geotiff files which have a white background. Because many of the tiffs overlap, I need a way to create transparent tiffs (set white as the transparency color). Does anybody know how to do this?

This is the output from gdalinfo:

C:\Programs\FWTools0.9.8>gdalinfo D:\wormerland\new\De_Poel.tif
Driver: GTiff/GeoTIFF
Size is 8677, 4811
Coordinate System is `'
GCP Projection =
GCP[  0]: Id=1, Info=
          (1457.5,1476.75) -> (114791,502268,0)
GCP[  1]: Id=2, Info=
          (672,4319.25) -> (114759,501887,0)
GCP[  2]: Id=3, Info=
          (2465.88,1705.75) -> (114921,502250,0)
GCP[  3]: Id=4, Info=
          (6097.5,1095.75) -> (115360,502420,0)
GCP[  4]: Id=5, Info=
          (3687.38,1458.75) -> (115069,502315,0)
Metadata:
  TIFFTAG_SOFTWARE=Oi/GFS, writer v00.06.02
  TIFFTAG_XRESOLUTION=200
  TIFFTAG_YRESOLUTION=200
  TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)
Corner Coordinates:
Upper Left  (    0.0,    0.0)
Lower Left  (    0.0, 4811.0)
Upper Right ( 8677.0,    0.0)
Lower Right ( 8677.0, 4811.0)
Center      ( 4338.5, 2405.5)
Band 1 Block=8677x1 Type=Byte, ColorInterp=Red
Band 2 Block=8677x1 Type=Byte, ColorInterp=Green
Band 3 Block=8677x1 Type=Byte, ColorInterp=Blue

Thanks in advance.

Best regards,
Bart

Bart van den Eijnden
Syncera-ITSolutions
Postbus 270
2600 AG  DELFT

tel.nr.: 015-7512436
email: BEN at Syncera-ITSolutions.nl