[Gdal-dev] gdalwarp Transparency Question

[Frank Warmerdam]

Reinaldo Escada Chohfi wrote:
> Matt,
> 
> I've been successfully using the attached command lines in .bat files to 
> crop and mosaic a large number of tiles.  Frank suggested to use 
> gdalwarp because my input images are large (approx. 2 GB each) and 
> gdal_merge loads entire images in memory and I was running into 
> problems. You have to use gdal_merge first to create the image and them 
> use gdalwarp to mosaic.  In my case the src and dst srs are the same.
> 
> I also use gdal_translate because I load the tiles into another program 
> that wants tiffs as INTERLEAVE=PIXEL.

Reinaldo,

I would add that gdalwarp should now support many input files, like
gdal_merge, and that creation options can be used directly with gdalwarp.
So, in theory your case could be expressed as:

gdalwarp -te 569600 10064800 578300 10057600 C:\Subsets\input\*.tif CD-043.tif
          -co INTERLEAVE=PIXEL

The many files in gdalwarp support was new for GDAL 1.3.2 in an effort
to de-emphasize gdal_merge.py.

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