I've created a hillshade image using the NASA SRTM3 data following the
notes at: http://wiki.openstreetmap.org/wiki/HikingBikingMaps. Looks
great except for the occasional 'black hole' in the image, I expect
this is due to data voids not being rendered correctly.
What's got me puzzled about this is that the wiki page suggests using
a value of 32767 for the -srcnodata and -dstnodata options to
gdalwarp, howver in the NASA docs (http://dds.cr.usgs.gov/srtm/version2_1/Documentation/Quickstart.pdf
) it says data voids are assigned the value -32768.
Should I be using the NASA value for -srcnodata and -dstnodata instead?
Cheers
Adam Ratcliffe
Software Developer
GeoSmart
PO Box 101001
29 Apollo Drive, Mairangi Bay, Auckland, NZ
Ph: +64 9 9668757 Fx: +64 9 966 8721
Email: [email protected]
Web: www.GeoSmart.co.nz
SmartNAV - The premier Car Navigation dataset for NZ
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