[FWTools] ECW Conversion and TIF Tiling

[Frank Warmerdam]

Eric Legge Smith wrote:
> Hello List,
> 
> Newbie questions -
> I'm looking for documentation on how to use FWTools to...
> (1) convert an ECW raster to an indexed set of tiled TIFs?
> (2) convert a 1.5Gb TIF with an external 'tfw' file to a set of tiled TIF's?
> (3) crop the 1.5Gb TIF with external 'tfw' file and convert to  a GeoTIFF

Eric,

As I think Travis mentioned, there is no handing tiling tool in FWTools.
I will mention that you could write a python script to do this, but it isn't
exactly trivial.  The easiest approach is like to write a batch script of some
kind using gdal_translate with varying -srcwin (or -projwin) windows for each
tile.

I will note that gdal_translate will by default produce a geotiff from a
TIFF+tfw, but if you want to provide a coordinate system to you need to
specify that on the commandline.  The following would read in.tif (and in.tfw)
and produce an output out.tif GeoTIFF file with the georeferencing info and
the coordinate system set to UTM 11 WGS84.

eg.
gdal_translate in.tif out.tif -a_srs '+proj=utm +zone=11 +datum=WGS84'

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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