[Geoserver-users] Difference in the resolution between WMS and WCS Geoserver 1.5.0 queries

GeoServer GeoServer User
1

FYI below I had to remove the attachments since geoserver-users@lists.sourceforge.net would not allow these attachments.

On 5/4/07, John Mitchell <mitchelljj98@anonymised.com> wrote:

Hi,

I have run the identical queries against a pyramid within geoserver 1.5.0 one is a wms query and the other is a wcs query.

The WCS query generates a GeoTiff which accurately renders the 6 inch GeoTiff with full resolution.
Note this image also has the same resolution from what is generated from UMN MapServer.
The query is the following:
https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID=

The WMS query generates a image/png within a web page and looks like 1/4 resolution of the original.
The query is the following:
https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=

As you can see above the queries are identical except for: wms is wcs, version=1.1.1 is 1.0.0, REQUEST=GetMap is GetCoverage, Layers is Coverage, SRS is CRS, and FORMAT=image/png is GeoTiff.

Why would an identical query generate such a difference in the resolution?

Thanks,

John Mitchell

On 5/1/07, John Mitchell < mitchelljj98@anonymised.com> wrote:

Andrea,

I have attached a geotiff file as you requested.

John

On 4/27/07, Andrea Aime < aaime@anonymised.com > wrote:

John Mitchell ha scritto:

Hi,

I tried enabling bilinear interpolation in the WMS settings, and I still
have the issue with 6 inch geotiff data pixelizing much sooner with
geoserver compared to mapserver or the desktop application global
mapper. I did find that a different 20 meter geotiff did not pixelize
prematurely compared to other applications like the 6 inch geotiff did.
So maybe geoserver just has a problem very high resolution imagery like
6 inch.

Has anyone who has both used geoserver and umn mapserver (in the past)
for high resolution geotiff’s had similar problems?

Nope. As you can see, imagery support in Geoserver is pretty new…
can you provide us a data sample?

Cheers
Andrea

–
John J. Mitchell

–
John J. Mitchell

–
John J. Mitchell

2

John Mitchell ha scritto:

    Hi,

    I have run the identical queries against a pyramid within geoserver
    1.5.0 one is a wms query and the other is a wcs query.

    The WCS query generates a GeoTiff which accurately renders the 6
    inch GeoTiff with full resolution.
    Note this image also has the same resolution from what is generated
    from UMN MapServer.
    The query is the following:
    https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
    <https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID=&gt;

    The WMS query generates a image/png within a web page and looks like
    1/4 resolution of the original.
    The query is the following:
    https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
    <https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=&gt;

    As you can see above the queries are identical except for: wms is
    wcs, version=1.1.1 is 1.0.0, REQUEST=GetMap is GetCoverage, Layers
    is Coverage, SRS is CRS, and FORMAT=image/png is GeoTiff.

    Why would an identical query generate such a difference in the
    resolution?

John, I've just tried out the current version of Geoserver, comparing
its rendering with the OpenEV one (part of the FWTools distribution),
and with QGIS, which both use the same raster access library as MapServer, and using the GeoTIFF you sent me by private mail.
Once you disable subpixel interpolation in OpenEV, so that you can see the real pixels as they are, the three of them generate exactly the same image. (I've sent you a sample where you can see exactly the same pixels
in the three images).

May it be that you're just looking for subpixel interpolation, since it's not enabled by default in Geoserver 1.5.0? If so, go in the
WMS configuration section (Config/WMS/Rendering) and play with
the interpolation settings.

Let me know
Cheers
Andrea

3

Andrea,

I tried the other settings for Config/WMS/Rendering and I still get the problem with the image pixelizing sooner than it should be.
I ran the identical query as a GetCoverage request and outputted as png and the image is as expected, so that don’t understand how the identical query with the only differerence that it is GetCoverage/WCS instead GetMap/WMS would generate such a difference in resolution?
GetCoverage query with full resolution link below:
https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
GetMap query with 1/4 resolution link below:
https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=

John

On 5/7/07, Andrea Aime <aaime@anonymised.com> wrote:

John Mitchell ha scritto:

Hi,

I have run the identical queries against a pyramid within geoserver
1.5.0 one is a wms query and the other is a wcs query.

The WCS query generates a GeoTiff which accurately renders the 6
inch GeoTiff with full resolution.
Note this image also has the same resolution from what is generated
from UMN MapServer.
The query is the following:
https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
< https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID= >

The WMS query generates a image/png within a web page and looks like
1/4 resolution of the original.
The query is the following:
https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
< https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID= >

As you can see above the queries are identical except for: wms is
wcs, version=1.1.1 is 1.0.0, REQUEST=GetMap is GetCoverage, Layers
is Coverage, SRS is CRS, and FORMAT=image/png is GeoTiff.

Why would an identical query generate such a difference in the
resolution?

John, I’ve just tried out the current version of Geoserver, comparing
its rendering with the OpenEV one (part of the FWTools distribution),
and with QGIS, which both use the same raster access library as
MapServer, and using the GeoTIFF you sent me by private mail.
Once you disable subpixel interpolation in OpenEV, so that you can see
the real pixels as they are, the three of them generate exactly the same
image. (I’ve sent you a sample where you can see exactly the same pixels
in the three images).

May it be that you’re just looking for subpixel interpolation, since
it’s not enabled by default in Geoserver 1.5.0? If so, go in the
WMS configuration section (Config/WMS/Rendering) and play with
the interpolation settings.

Let me know
Cheers
Andrea

–
John J. Mitchell

4

Hi,

The problems that I have mentioned within previous emails are when I am utilizing the mosaic plug-in and the pyramid plug-in to reference these mosaics. I just tried accessing one of these tiles directly via “Tagged Image File Format with Geographic Information” option within Geoserver and I get full resolution as is expected, so it must be one of the parameters within the mosiac or the pyramid. I brought up the full resolution mosaic in order to see if I get full resolution, and I get the same problem with the image showing up as 1/4 resolution instead of full resolution.
I have attached the shape files, properties file and projection file along with the gdalinfo dump of one the geotiff files.

John

On 5/7/07, John Mitchell <mitchelljj98@anonymised.com> wrote:

Andrea,

I tried the other settings for Config/WMS/Rendering and I still get the problem with the image pixelizing sooner than it should be.
I ran the identical query as a GetCoverage request and outputted as png and the image is as expected, so that don’t understand how the identical query with the only differerence that it is GetCoverage/WCS instead GetMap/WMS would generate such a difference in resolution?
GetCoverage query with full resolution link below:
https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
GetMap query with 1/4 resolution link below:
https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=

John

On 5/7/07, Andrea Aime < aaime@anonymised.com> wrote:

John Mitchell ha scritto:

Hi,

I have run the identical queries against a pyramid within geoserver
1.5.0 one is a wms query and the other is a wcs query.

The WCS query generates a GeoTiff which accurately renders the 6
inch GeoTiff with full resolution.
Note this image also has the same resolution from what is generated
from UMN MapServer.
The query is the following:
https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
< https://localhost:8443/geoserver_extra/wcs?VERSION=1.0.0&REQUEST=GetCoverage&SERVICE=WCS&COVERAGE=gv:stlouis&CRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=GeoTIFF&STYLES=&TRANSPARENT=TRUE&UNIQUEID= >

The WMS query generates a image/png within a web page and looks like
1/4 resolution of the original.
The query is the following:
https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID=
< https://localhost:8443/geoserver_extra/wms?VERSION=1.1.1&REQUEST=GetMap&SERVICE=WMS&Layers=gv:stlouis&SRS=EPSG:4326&BBOX=-90.19327277589079,38.62381624049176,-90.19254329251484,38.62423204601606&WIDTH=800&HEIGHT=456&FORMAT=image/png&STYLES=&TRANSPARENT=TRUE&UNIQUEID= >

As you can see above the queries are identical except for: wms is
wcs, version=1.1.1 is 1.0.0, REQUEST=GetMap is GetCoverage, Layers
is Coverage, SRS is CRS, and FORMAT=image/png is GeoTiff.

Why would an identical query generate such a difference in the
resolution?

John, I’ve just tried out the current version of Geoserver, comparing
its rendering with the OpenEV one (part of the FWTools distribution),
and with QGIS, which both use the same raster access library as
MapServer, and using the GeoTIFF you sent me by private mail.
Once you disable subpixel interpolation in OpenEV, so that you can see
the real pixels as they are, the three of them generate exactly the same
image. (I’ve sent you a sample where you can see exactly the same pixels
in the three images).

May it be that you’re just looking for subpixel interpolation, since
it’s not enabled by default in Geoserver 1.5.0? If so, go in the
WMS configuration section (Config/WMS/Rendering) and play with
the interpolation settings.

Let me know
Cheers
Andrea

–
John J. Mitchell

–
John J. Mitchell

stlouis.dbf (24.1 KB)

fullResolution.prj (675 Bytes)

stlouis.properties (126 Bytes)

stlouis.shp (12.8 KB)

stlouis.shx (868 Bytes)

gdalinfo.txt (1.57 KB)

5

John Mitchell ha scritto:

Hi,

The problems that I have mentioned within previous emails are when I am utilizing the mosaic plug-in and the pyramid plug-in to reference these mosaics. I just tried accessing one of these tiles directly via "Tagged Image File Format with Geographic Information" option within Geoserver and I get full resolution as is expected, so it must be one of the parameters within the mosiac or the pyramid. I brought up the full resolution mosaic in order to see if I get full resolution, and I get the same problem with the image showing up as 1/4 resolution instead of full resolution.
I have attached the shape files, properties file and projection file along with the gdalinfo dump of one the geotiff files.

Ah, I see. Well, for the next 4 days I won't be working on Geoserver at all, besides that, there are more qualified people to answer your
question.
Simone, Alessio, does this report ring a bell to you?
Cheers
Andrea