Hi, I've brought up this issue on stackoverflow but thought I'd get better visibility here. https://stackoverflow.com/questions/47019616/gdal-doesnt-recognize-bipolar-conic-western-hemisphere-projection
I'm having trouble with a particular projection. It seems supported within proj4 (http://proj4.org/usage/operations/projections/bipc.html) But when I use it within gdal it's as if it doesnt exist: gdalsrsinfo: ``` gdalsrsinfo -o proj4 "+proj=bipc +ns" ``` yields ``` failed to load SRS definition ``` gdalwarp: ``` gdalwarp -overwrite -s_srs EPSG:4326 -t_srs "+proj=bipc +ns" -of GTiff in.tiff out.tiff ``` yields ``` ERROR 1: Translating source or target SRS failed: +proj=bipc +ns ``` Also, running `proj -lp` lists it bipc : Bipolar conic of western hemisphere. These commands work fine for me with more common (re)projections, and I've tried this on GDAL 1.11.5 and 2.2.2. I was able to get this sort of to work within a mapbox rasterio script (not sure what the difference is, given that it is GDAL powered). There's a different problem. I'm doing a reprojection from WGS84 raster data to "+proj=bipc +ns" and it blots out a bunch of the data through the center of the image. Before: <http://osgeo-org.1560.x6.nabble.com/file/t382003/Screen_Shot_1.png> After: <http://osgeo-org.1560.x6.nabble.com/file/t382003/Screen_Shot_2.png> (NODATA is black) This seems like some sort of artifact from the hybrid nature of the projection (http://www.quadibloc.com/maps/images/bocc.gif). But I'm not sure how to remedy this. I can put `SOURCE_EXTRA=1000 SAMPLE_GRID=YES SAMPLE_STEPS=100` gdalwarp flags in the rasterio script (a la http://osgeo-org.1560.x6.nabble.com/gdalwarp-cutting-off-projected-image-td3756390.html) but they dont seem to have an effect. The relevant rasterio code is here ``` destCrs = rasterio.crs.CRS.from_string("+proj=bipc +ns") width = 3142 height = 4788 bounds = rasterio.coords.BoundingBox(left=-8140886.583, bottom=-11629369.004, right=6276024.286, top=10340131.073) affine = rasterio.transform.from_bounds(bounds.left, bounds.bottom, bounds.right, bounds.top, width, height) bandIn = src.read(1) np.putmask(bandIn, bandIn < 0, 0) bandOut = np.empty((height, width), np.float32) reproject( source=bandIn, destination=bandOut, src_transform=src.affine, src_crs=src.crs, dst_transform=affine, dst_crs=destCrs, resampling=RESAMPLING.nearest, # Commented out GDAL flags for now: # SOURCE_EXTRA=1000, SAMPLE_GRID="YES", SAMPLE_STEPS=100 ) ``` Thanks for any help on either route. -- Sent from: http://osgeo-org.1560.x6.nabble.com/GDAL-Dev-f3742093.html _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
