[Geoserver-users] WCS Cell Size

Jukka_Rahkonen · September 4, 2014, 8:56pm

Hi,

Perhaps we should have some WCS GET demo request. I have an initial list here:

http://localhost:8080/geoserver/ows?service=wcs&version=1.1.1&request=GetCapabilities

http://localhost:8080/geoserver/ows?service=wcs&version=1.1.1&request=DescribeCoverage&identifiers=mosaic

http://localhost:8080/geoserver/ows?service=wcs&version=1.1.1&request=GetCoverage&identifier=mosaic&BoundingBox=41,8,42,9,urn:ogc:def:crs:EPSG:4326&RangeSubset=contents&format=image/png&store=true

http://localhost:8080/geoserver/ows?service=wcs&version=1.1.1&request=GetCoverage&identifier=mosaic&BoundingBox=41,8,42,9,urn:ogc:def:crs:EPSG:4326&RangeSubset=contents&format=image/png&store=true&GridOffsets=0.01,0,0,0.01

->requires 2

http://localhost:8080/geoserver/ows?service=wcs&version=1.1.1&request=GetCoverage&identifier=mosaic&BoundingBox=41,8,42,9,urn:ogc:def:crs:EPSG:4326&RangeSubset=contents&format=image/png&store=true&GridOffsets=0.01,0.01

->works

http://localhost:8080/geoserver/ows?service=wcs&version=1.1.1&request=GetCoverage&identifier=mosaic&BoundingBox=41,8,42,9,urn:ogc:def:crs:EPSG:4326&RangeSubset=contents&format=image/png&store=true&GridOffsets=0.001,0.001

->gives different size

-Jukka-

···

Lähettäjä: Timothy Astle [mailto:timothy.astle@anonymised.com]
Lähetetty: 4. syyskuuta 2014 17:20
Vastaanottaja: geoserver-users@lists.sourceforge.net
Aihe: Re: [Geoserver-users] WCS Cell Size

I’m not going to be of much help on this.

I’ve noticed some very odd stuff with WCS.

http://sedac.ciesin.columbia.edu/geoserver/ows?SERVICE=WCS&VERSION=1.1.1&REQUEST=DescribeCoverage&IDENTIFIERS=species-v1-global-amphibian-family-richness

Things I’ve observed are:

The grid definition’s axis ordering doesn’t obey the coordinate reference systems’ axis ordering.
** http://osgeo-org.1560.x6.nabble.com/WCS-Img-Sample-GridOrigin-and-GridOffsets-appear-flipped-td5158701.html
** In your example, the origin values look like they should be reversed, but I don’t believe it’s something you did.
Apparent upsampling of data.
** http://osgeo-org.1560.x6.nabble.com/WCS-GetCoverage-The-smaller-the-bounding-box-the-more-data-you-get-td5158916.html

The offsets indicate a direction (sign) and distance from the origin. Your current origin is -179.991667 84.99436. Did you try defining the entire output grid in your KVP request to see if it gets you closer to what you want? (i.e., Adding your GridOrigin.)

Tim

On 04/09/2014 10:39 AM, Kytt MacManus wrote:

Hello and good day,

I have what I think is a simple question.  I am trying to make a WCS

1.1.1 GetCoverage request to a Geoserver running version 2.5

[http://sedac.ciesin.columbia.edu/geoserver/ows?SERVICE=WCS&VERSION=1.1.1&REQUEST=GetCoverage&IDENTIFIER=species-v1-global-amphibian-family-richness&FORMAT=image%2Ftiff&BOUNDINGBOX=42.0,16.0,45.5,18.5,urn:ogc:def:crs:EPSG:4326&RangeSubset=contents&GridOffsets=0.008333,0.008333](http://sedac.ciesin.columbia.edu/geoserver/ows?SERVICE=WCS&VERSION=1.1.1&REQUEST=GetCoverage&IDENTIFIER=species-v1-global-amphibian-family-richness&FORMAT=image%2Ftiff&BOUNDINGBOX=42.0,16.0,45.5,18.5,urn:ogc:def:crs:EPSG:4326&RangeSubset=contents&GridOffsets=0.008333,0.008333)

For some reason the TIFF that is returned has an irregular cell size of:

0.005952381, 0.011666667

The expected cell size are the contents of GridOffsets=0.008333,0.008333

What am I doing wrong?

Many thanks,

Kytt