[Geoserver-users] Borders around geotiff image mosaic

GeoServer GeoServer User
1

Hello,

I have a number of geotiff files that I'm attempting to mosaic and use
as an overlay on top of a base map. My problem is that I can't get rid
of the a border on the boundary of the geotiff mosaic. I've set
BackgroundValues to -9999 and the OutputTransparentColor to 000000
which takes care of most of the area not occupied by images.

The border seems to occur at almost all edges. For instance, I've
attached an image of the open layers preview for the west coast of the
US. (The actual image data is removed and replaced with a gray field.)
There are three tiles present in this portion of the mosaic, I'm
attempting to get rid of the blue border. The white area to the left
is what I want, transparent tiles. This blue border changes width
depending on the zoom level and the suggested_tile_size setting. The
bigger the tile size the wider the border.

The border isn't part of the geotiffs, I've checked, and I have no
idea why it is blue. I can try to make the border insubstantial by
changing the suggested_tile_size to something insanely small, but that
isn't an acceptable solution (it is already 32,32 in the attached
image)

Any suggestions?

Thanks,

Mark

GeoTiff_Border.png

2

Ciao Mark,
please, read below...

Regards,
Simone Giannecchini

GeoServer training in Milan, 6th & 7th June 2013! Visit
http://geoserver.geo-solutions.it for more information.

Ing. Simone Giannecchini
@simogeo
Founder/Director

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 333 8128928

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

-------------------------------------------------------

On Mon, Jun 3, 2013 at 9:37 PM, Mark <kc8khl2@anonymised.com> wrote:

Hello,

I have a number of geotiff files that I'm attempting to mosaic and use
as an overlay on top of a base map. My problem is that I can't get rid
of the a border on the boundary of the geotiff mosaic. I've set
BackgroundValues to -9999 and the OutputTransparentColor to 000000
which takes care of most of the area not occupied by images.

Can you paster here the output of the gdalinfo tool on one of these images?

Rationale. If your geotiff are RGB and they contain black portions we
can use the InputTransparentColor to remove such areas.
If the overall mosaic has holes (portions not covered by data) I would
suggest to set the BackgroundValues to 0 and leave the
OutputTransparentColor to 000000.
This is a two steps approach:
-1- use InputTransparentColor to remove blackportions within the images
-2- use BackgroundValues to ask for a black background
-3- use OutputTransparentColor to make the background go away

ok, that was 3 steps, but I guess you got the idea :slight_smile:

The border seems to occur at almost all edges. For instance, I've
attached an image of the open layers preview for the west coast of the
US. (The actual image data is removed and replaced with a gray field.)
There are three tiles present in this portion of the mosaic, I'm
attempting to get rid of the blue border. The white area to the left
is what I want, transparent tiles. This blue border changes width
depending on the zoom level and the suggested_tile_size setting. The
bigger the tile size the wider the border.

Thinking, this is actually strange. If you configure the geotiff as a
single geotiff store does it look differently?
Which version of GeoServer are you working with?

The border isn't part of the geotiffs, I've checked, and I have no
idea why it is blue. I can try to make the border insubstantial by
changing the suggested_tile_size to something insanely small, but that
isn't an acceptable solution (it is already 32,32 in the attached
image)

K, this answer partially to my question above, however the gdalinfo
would be very useful anyway.
It would be probably also good to have access to a couple of samples
to reproduce the issue. You can
send them privately if you wish.

Any suggestions?

Thanks,

Mark

------------------------------------------------------------------------------
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1. A cloud service to automate IT design, transition and operations
2. Dashboards that offer high-level views of enterprise services
3. A single system of record for all IT processes
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3

Caio Simone,

Here is the output of gdalinfo and I suppose that explains where the
blue color comes from since the color map defines 0 as exactly that
shade of blue.

Based on your comments and that colormap I set the BackgroundValues to
255 and both InputTransparentColor and OutputTransparentColor to
#000000. Now everything works wonderfully. I suppose I should have
studied that gdalinfo dump a little closer!

Thanks for the help.

Mark

Driver: GTiff/GeoTIFF
Files: ***.tif
Size is 2168, 2208
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-97.277345999999994,49.416856000000003)
Pixel Size = (0.003600000000000,-0.002700000000000)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left ( -97.2773460, 49.4168560) ( 97d16'38.45"W, 49d25'0.68"N)
Lower Left ( -97.2773460, 43.4552560) ( 97d16'38.45"W, 43d27'18.92"N)
Upper Right ( -89.4725460, 49.4168560) ( 89d28'21.17"W, 49d25'0.68"N)
Lower Right ( -89.4725460, 43.4552560) ( 89d28'21.17"W, 43d27'18.92"N)
Center ( -93.3749460, 46.4360560) ( 93d22'29.81"W, 46d26'9.80"N)
Band 1 Block=2168x3 Type=Byte, ColorInterp=Palette
  Color Table (RGB with 256 entries)
    0: 7,23,178,255
    1: 247,245,245,255
    2: 124,137,224,255
    3: 245,237,226,255
... snip ...
  214: 21,47,9,255
  215: 51,17,66,255
  216: 0,0,0,255
  217: 0,0,0,255
  218: 0,0,0,255
... snip ...
  253: 0,0,0,255
  254: 0,0,0,255
  255: 0,0,0,255

On Tue, Jun 4, 2013 at 6:38 AM, Simone Giannecchini
<simone.giannecchini@anonymised.com> wrote:

Ciao Mark,
please, read below...

Regards,
Simone Giannecchini

GeoServer training in Milan, 6th & 7th June 2013! Visit
http://geoserver.geo-solutions.it for more information.

Ing. Simone Giannecchini
@simogeo
Founder/Director

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 333 8128928

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

-------------------------------------------------------

On Mon, Jun 3, 2013 at 9:37 PM, Mark <kc8khl2@anonymised.com> wrote:

Hello,

I have a number of geotiff files that I'm attempting to mosaic and use
as an overlay on top of a base map. My problem is that I can't get rid
of the a border on the boundary of the geotiff mosaic. I've set
BackgroundValues to -9999 and the OutputTransparentColor to 000000
which takes care of most of the area not occupied by images.

Can you paster here the output of the gdalinfo tool on one of these images?

Rationale. If your geotiff are RGB and they contain black portions we
can use the InputTransparentColor to remove such areas.
If the overall mosaic has holes (portions not covered by data) I would
suggest to set the BackgroundValues to 0 and leave the
OutputTransparentColor to 000000.
This is a two steps approach:
-1- use InputTransparentColor to remove blackportions within the images
-2- use BackgroundValues to ask for a black background
-3- use OutputTransparentColor to make the background go away

ok, that was 3 steps, but I guess you got the idea :slight_smile:

The border seems to occur at almost all edges. For instance, I've
attached an image of the open layers preview for the west coast of the
US. (The actual image data is removed and replaced with a gray field.)
There are three tiles present in this portion of the mosaic, I'm
attempting to get rid of the blue border. The white area to the left
is what I want, transparent tiles. This blue border changes width
depending on the zoom level and the suggested_tile_size setting. The
bigger the tile size the wider the border.

Thinking, this is actually strange. If you configure the geotiff as a
single geotiff store does it look differently?
Which version of GeoServer are you working with?

The border isn't part of the geotiffs, I've checked, and I have no
idea why it is blue. I can try to make the border insubstantial by
changing the suggested_tile_size to something insanely small, but that
isn't an acceptable solution (it is already 32,32 in the attached
image)

K, this answer partially to my question above, however the gdalinfo
would be very useful anyway.
It would be probably also good to have access to a couple of samples
to reproduce the issue. You can
send them privately if you wish.

Any suggestions?

Thanks,

Mark

------------------------------------------------------------------------------
How ServiceNow helps IT people transform IT departments:
1. A cloud service to automate IT design, transition and operations
2. Dashboards that offer high-level views of enterprise services
3. A single system of record for all IT processes
http://p.sf.net/sfu/servicenow-d2d-j
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users

4

Ciao Mark,
problem solved then :slight_smile:

Just for the uninitiated a quick explanation.

The BackgroundValues can be used to set the value to be used in gaps
for mosaic. In this case a value of 0 means "use the first color in
the color table" as the mosaics are paletted images
and the 0 index point to a blue color.

InputTransparentColor and OutputTransparentColor works in color space
(e.g. with color) hence asking black to become transpare really means
asking black to become transparent :slight_smile:

So in this case, to be on the safe side, we ask ImageMosaic to turn
black pixels in single granules to transparent via the
InputTransparentColor, then we fill the gaps with 255 to make the gaps
black as well and then we use OutputTransparentColor for black to
turn the black pixels in the final mosaic to transparent.

Side note, I believe in this case it might be enough to set
BackgroundValues and OutputTransparentColor. It is worth a try as it
would make image serving faster (less operations).

Ing. Simone Giannecchini
@simogeo
Founder/Director

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 333 8128928

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

-------------------------------------------------------

On Tue, Jun 4, 2013 at 2:49 PM, Mark <kc8khl2@anonymised.com> wrote:

Caio Simone,

Here is the output of gdalinfo and I suppose that explains where the
blue color comes from since the color map defines 0 as exactly that
shade of blue.

Based on your comments and that colormap I set the BackgroundValues to
255 and both InputTransparentColor and OutputTransparentColor to
#000000. Now everything works wonderfully. I suppose I should have
studied that gdalinfo dump a little closer!

Thanks for the help.

Mark

Driver: GTiff/GeoTIFF
Files: ***.tif
Size is 2168, 2208
Coordinate System is:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0],
    UNIT["degree",0.0174532925199433],
    AUTHORITY["EPSG","4326"]]
Origin = (-97.277345999999994,49.416856000000003)
Pixel Size = (0.003600000000000,-0.002700000000000)
Metadata:
  AREA_OR_POINT=Area
Image Structure Metadata:
  INTERLEAVE=BAND
Corner Coordinates:
Upper Left ( -97.2773460, 49.4168560) ( 97d16'38.45"W, 49d25'0.68"N)
Lower Left ( -97.2773460, 43.4552560) ( 97d16'38.45"W, 43d27'18.92"N)
Upper Right ( -89.4725460, 49.4168560) ( 89d28'21.17"W, 49d25'0.68"N)
Lower Right ( -89.4725460, 43.4552560) ( 89d28'21.17"W, 43d27'18.92"N)
Center ( -93.3749460, 46.4360560) ( 93d22'29.81"W, 46d26'9.80"N)
Band 1 Block=2168x3 Type=Byte, ColorInterp=Palette
  Color Table (RGB with 256 entries)
    0: 7,23,178,255
    1: 247,245,245,255
    2: 124,137,224,255
    3: 245,237,226,255
... snip ...
  214: 21,47,9,255
  215: 51,17,66,255
  216: 0,0,0,255
  217: 0,0,0,255
  218: 0,0,0,255
... snip ...
  253: 0,0,0,255
  254: 0,0,0,255
  255: 0,0,0,255

On Tue, Jun 4, 2013 at 6:38 AM, Simone Giannecchini
<simone.giannecchini@anonymised.com> wrote:

Ciao Mark,
please, read below...

Regards,
Simone Giannecchini

GeoServer training in Milan, 6th & 7th June 2013! Visit
http://geoserver.geo-solutions.it for more information.

Ing. Simone Giannecchini
@simogeo
Founder/Director

GeoSolutions S.A.S.
Via Poggio alle Viti 1187
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272
mob: +39 333 8128928

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

-------------------------------------------------------

On Mon, Jun 3, 2013 at 9:37 PM, Mark <kc8khl2@anonymised.com> wrote:

Hello,

I have a number of geotiff files that I'm attempting to mosaic and use
as an overlay on top of a base map. My problem is that I can't get rid
of the a border on the boundary of the geotiff mosaic. I've set
BackgroundValues to -9999 and the OutputTransparentColor to 000000
which takes care of most of the area not occupied by images.

Can you paster here the output of the gdalinfo tool on one of these images?

Rationale. If your geotiff are RGB and they contain black portions we
can use the InputTransparentColor to remove such areas.
If the overall mosaic has holes (portions not covered by data) I would
suggest to set the BackgroundValues to 0 and leave the
OutputTransparentColor to 000000.
This is a two steps approach:
-1- use InputTransparentColor to remove blackportions within the images
-2- use BackgroundValues to ask for a black background
-3- use OutputTransparentColor to make the background go away

ok, that was 3 steps, but I guess you got the idea :slight_smile:

The border seems to occur at almost all edges. For instance, I've
attached an image of the open layers preview for the west coast of the
US. (The actual image data is removed and replaced with a gray field.)
There are three tiles present in this portion of the mosaic, I'm
attempting to get rid of the blue border. The white area to the left
is what I want, transparent tiles. This blue border changes width
depending on the zoom level and the suggested_tile_size setting. The
bigger the tile size the wider the border.

Thinking, this is actually strange. If you configure the geotiff as a
single geotiff store does it look differently?
Which version of GeoServer are you working with?

The border isn't part of the geotiffs, I've checked, and I have no
idea why it is blue. I can try to make the border insubstantial by
changing the suggested_tile_size to something insanely small, but that
isn't an acceptable solution (it is already 32,32 in the attached
image)

K, this answer partially to my question above, however the gdalinfo
would be very useful anyway.
It would be probably also good to have access to a couple of samples
to reproduce the issue. You can
send them privately if you wish.

Any suggestions?

Thanks,

Mark

------------------------------------------------------------------------------
How ServiceNow helps IT people transform IT departments:
1. A cloud service to automate IT design, transition and operations
2. Dashboards that offer high-level views of enterprise services
3. A single system of record for all IT processes
http://p.sf.net/sfu/servicenow-d2d-j
_______________________________________________
Geoserver-users mailing list
Geoserver-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/geoserver-users