[gdal-dev] Conversion from ASCII to GeoTIFF with gdalwarp: incorrect output

[Andre Joost]

Am 12.10.2014 22:43, schrieb Lukasz Tracewski:
> Hi, I have a few thousands of ESRI ASCII rasters in World_Mollweide
> (EPSG:54009) projection, which I need to convert to GeoTIFF. Usually
> it goes fine, but there are certain special cases that resist
> peaceful conversion. They are all placed on Fiji, which is special in
> a sense being on very border of a world's map.

> Thing is if I crop the ASCII in QGIS to include only left side of the
> image, then it's fine. If I take the right side, then again I get
> incorrect output.

Your dataset crosses the 180° meridian, that's why gdalwarp does not 
like reprojecting to EPSG:4326.

What you can do:

- Reproject to a transverse mercator projection with 180° as central 
meridian

- Clip your raster at 180° (or rather +/- 179.95°). Thats not very 
difficult if you have done the tmerc reprojection.

- translate the data to XYZ format and import that as delimited text 
point data. Reprojection of points is a lot easier.

HTH,
André Joost