[Gdal-dev] gdalwarp on CADRG / gltp: maps

[Leibold, David]

I'm trying to reproject some CADRG map files to UTM grid with gdalwarp.

gdalwarp straightens out individual tiles OK (e.g. *.TL2 files), then gdal_merge can build the full map from the tiles.

But when I attempt gdalwarp on the entire CADRP map using OGDI gltp:/rpf addressing, it always produces all-black images (albeit georeferenced images, when default GeoTiff output is used).

Do I need other options in gdalwarp for CADRG reprojections? Or will I have to warp and merge the individual tiles?


Further detail on what I tried:

gltp: addressing and OGDI seems to be working - gdalinfo produces info on the CADRG map with a gltp: address.

gdalwarp was tried with both the Matrix and Image datasets on the CADRG. No error messages were seen.

Example command:

C:>gdalwarp -t_srs "+proj=utm +zone=19 +datum=wgs84" "gltp:/rpf/map1/rpf" test99.tif
Using band 4 of source image as alpha.
Creating output file that is 1993P x 2136L.
:0...10...20...30...40...50...60...70...80...90...100 - done.

gdalwarp was also tried using the more precise gltp: addresses for each subdataset listed in gdalinfo (Matrix and Image sets).

Also tried pre-processing with gdal_translate - even trying -b switches to try different image bands than #4 Alpha. Still got black maps.

Thanks.

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David Leibold