[mapserver-users] WCS 1.0 vs 1.1 image shifted

Ben Tuttle benjamin.tuttle at gmail.com
Fri Apr 30 16:18:08 EDT 2010


I am trying to understand the results I am getting from WCS requests
to MapServer.
If I make the same request changing only the WCS version the images I
get back are shifted by 1 pixel in the x and y directions. A request
for VERSION=1.1.0 gives me the image I expect while VERSION=1.0.0
gives me back an image shifted by 1 pixel in the x and y directions to
the North and West.
The underlying data and mapfile are the same in both cases. So I am
not sure if this is perhaps a MapServer bug or if perhaps I am reading
the WCS spec incorrectly and this is actually the intended result (I
hope it's not). Can anyone help me out?

Request Examples:
http://map.ngdc.noaa.gov/cgi-bin/mapserver/test_image_ms_wcs100_avgvis42_23_47_28.tif?map=../../../nfs/gisdata/mapserver/gcv4/index.map&request=GetCoverage&service=WCS&COVERAGE=F162008_v4_avg_vis&crs=EPSG:4326&VERSION=1.0.0&format=geotiff&resx=0.0083333333&resy=0.0083333333&bbox=42,23,47,28

http://map.ngdc.noaa.gov/cgi-bin/mapserver/test_image_ms_wcs110_avgvis42_23_47_28.tif?map=../../../nfs/gisdata/mapserver/gcv4/index.map&request=GetCoverage&service=WCS&COVERAGE=F162008_v4_avg_vis&crs=EPSG:4326&VERSION=1.1.0&format=geotiff&resx=0.0083333333&resy=0.0083333333&bbox=42,23,47,28


System Details:
MapServer version 5.6.3 OUTPUT=GIF OUTPUT=PNG OUTPUT=JPEG OUTPUT=WBMP
OUTPUT=SVG SUPPORTS=PROJ SUPPORTS=AGG SUPPORTS=FREETYPE SUPPORTS=ICONV
SUPPORTS=WMS_SERVER SUPPORTS=WMS_CLIENT SUPPORTS=WFS_SERVER
SUPPORTS=WFS_CLIENT SUPPORTS=WCS_SERVER SUPPORTS=SOS_SERVER
SUPPORTS=THREADS SUPPORTS=GEOS INPUT=TIFF INPUT=EPPL7 INPUT=POSTGIS
INPUT=ORACLESPATIAL INPUT=OGR INPUT=GDAL INPUT=SHAPEFILE

Red Hat Enterprise Linux Server release 5.5 (Tikanga)

-- 
Cheers, Ben Tuttle


More information about the mapserver-users mailing list