[gdal-dev] [Question]Output from gdal_translate projwin is different from geoserver WCS GetCoverage request?

[Pham Huu Bang]

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,
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