To our request defines the grid locations, you may have to read the standard to determine exactly how the grid is defined for your request. The standard is available on the OGC website.
Thanks On Mon, Apr 3, 2023 at 7:00 AM Pham Huu Bang <a09...@gmail.com> wrote: > Hello Jody, > > >I find WCS tricky to use, did you use the WCS Request Builder to produce > your curl command? > No, I didn't use any tool for that. The parameters in curl command are > standard WCS 2.0.1 GetCoverage request. > > >One thing I could not determine from your curl example is what what > target coverage layout is being used (which is probably what your question > is about). I am not sure if WCS 2 allows you to specify that manually or > not. > I'm not sure about this either. I used only standard parameters request > for WCS GetCoverage. > > >Given your raster contains both shifted pixels and one additional row > than anticipated by gdal. This may be a difference between sampling at the > grid locations defined (WCS), rather that defining a grid of pixels and > sampling in the middle of each pixel defined (gdal)? > I'm not sure about this either. I used GeoServer normally to create a data > source as one TIFF file, then published it as a Layer and I didn't define > any grid locations. > > On Mon, 3 Apr 2023 at 15:56, Jody Garnett <jody.garn...@gmail.com> wrote: > >> I find WCS tricky to use, did you use the WCS Request Builder to produce >> your curl command? >> >> One thing I could not determine from your curl example is what what >> target coverage layout is being used (which is probably what your question >> is about). I am not sure if WCS 2 allows you to specify that manually or >> not. >> >> Given your raster contains both shifted pixels and one additional row >> than anticipated by gdal. This may be a difference between sampling at the >> grid locations defined (WCS), rather that defining a grid of pixels and >> sampling in the middle of each pixel defined (gdal)? >> >> Jody >> >> On Mon, Apr 3, 2023 at 5:48 AM Pham Huu Bang <a09...@gmail.com> wrote: >> >>> Hello, >>> >>> I've a hard time understanding which one should be the correct result by >>> gdal_translate or GeoServer. >>> >>> My system (Ubuntu 22.04) has: >>> - GDAL 3.4.1 >>> - Geoserver 2.22 running on Tomcat on port 9090 >>> >>> I have a small tiff file (link to download at the bottom of this thread) >>> in EPSG:4326, then I wanted to have a small subset on Lat and Long axes >>> from it by running: >>> >>> - gdal_translate -projwin 137.915315044103 -36.51629558851893 >>> 154.64770004642423 -40.081875882617666 test.tif gdal.tif >>> >>> >>> - curl ' >>> http://localhost:9090/geoserver/wcs?service=WCS&version=2.0.1&request=GetCoverage&format=image/tiff&coverageId=test_raster:output&subset=Lat(-40.081875882617666,-36.51629558851893)&subset=Long(137.915315044103,154.64770004642423)' >>> -o geoserver.tiff >>> >>> - Then gdalinfo gdal.tif returns: >>> >>> Size is 17, 4 >>> >>> and gdalinfo geoserver.tif returns >>> >>> Size is 17, 3 >>> >>> - Also the geo bbox of gdal.tif and geoserver.tif are different. >>> First file gives: >>> >>> Upper Left ( 136.9750000, -35.9750000) >>> >>> Second file gives: >>> >>> Upper Left ( 137.9750000, -36.9750000) >>> >>> >>> More importantly, the pixels are shifted from gdal.tif at the top to >>> geoserver.tif at the bottom which you can see from this image: >>> https://imgur.com/a/L0vKvYk >>> >>> Here is the link to download test.tif, gdal.tif and geoserver.tif >>> https://drive.google.com/file/d/1dawCy38FMwx4J7OQsky-gAHHOXsMuDcy/view?usp=sharing >>> >>> Please share your opinion which result (gdal.tif or geoserver.tif) >>> should be correct? >>> >>> Thanks, >>> >>> _______________________________________________ >>> Geoserver-users mailing list >>> >>> Please make sure you read the following two resources before posting to >>> this list: >>> - Earning your support instead of buying it, but Ian Turton: >>> http://www.ianturton.com/talks/foss4g.html#/ >>> - The GeoServer user list posting guidelines: >>> http://geoserver.org/comm/userlist-guidelines.html >>> >>> If you want to request a feature or an improvement, also see this: >>> https://github.com/geoserver/geoserver/wiki/Successfully-requesting-and-integrating-new-features-and-improvements-in-GeoServer >>> >>> >>> Geoserver-users@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/geoserver-users >>> >> -- >> -- >> Jody Garnett >> > -- -- Jody Garnett
_______________________________________________ Geoserver-users mailing list Please make sure you read the following two resources before posting to this list: - Earning your support instead of buying it, but Ian Turton: http://www.ianturton.com/talks/foss4g.html#/ - The GeoServer user list posting guidelines: http://geoserver.org/comm/userlist-guidelines.html If you want to request a feature or an improvement, also see this: https://github.com/geoserver/geoserver/wiki/Successfully-requesting-and-integrating-new-features-and-improvements-in-GeoServer Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
