I have a Python script that I am using to load .asc raster files and then work with the contents therein. However, it isn't loading the correct information that is specified in the headers. The .asc file that I am using has the following for headers:
ncols 2131 nrows 2220 xllcorner 670813.505443912582 yllcorner 5480455.007973534055 cellsize 3.000109992417
But when I run the following simple script to obtain the values of xllcorner, yllcorner, and cellsize:
from osgeo import gdal dempath = 'My_DEM.asc' dem_file = gdal.Open(dempath) dem_transform = dem_file.GetGeoTransform() print(dem_transform)
I get the following as output:
(670813.5054439126, 3.000109992417, 0.0, 5487115.2521567, 0.0, -3.000109992417)
So as we can see, the yllcorner value that is loaded from the asc file isn't 5480455.007973534055, or any rounding off of it, that I would expect it to be. Instead I am getting 5487115.2521567, which is far off enough that it causes problems for me later on. I can import the correct header information with a variety of ways that are not using the GDAL Python wrappers, but ideally I'd like to keep using the GDAL Python wrappers. Is there something special I am forgetting to specify in my script like projection information? Is this a known bug in GDAL? How can I resolve this issue without having to write my own asc file parser?