large geotiff data file

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tkani tkani
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large geotiff data file

hi, i would like to know how the cache optimization could be used to display for example this kind of geotiff file:

http://dl.free.fr/getfile.pl?file=/tJ1JM3HH  : link to the geotiff file(571MB)

in order to make it works reproject it : gdalwarp -t_srs epsg:4326  mapoic.tif mapoicp.tif  (3800MB)

here is the earth file :

<map name="sample" type="globe">
<image name="test" driver="gdal">
        <url>mapoicp.tif</url>
        <tile_size>64</tile_size>
        <cache_format>
            png
    </cache_format>
</image>
</map>

in order to see the data on the globe make the viewpoint here :

osg::ref_ptr<osgEarthUtil::EarthManipulator> manip = new osgEarthUtil::EarthManipulator();
d_viewer.getViewer()->setCameraManipulator(manip);

osgEarthUtil::Viewpoint viewpoint(osg::Vec3d(-73.777, 40.57796, 0), 0, -90, 100000);
manip->setViewpoint(viewpoint, 3);


the processor is used a lot when I zoom in or zoom out, but the projection is normally already adapt, the <cache format> section dont seems to improve (perhaps I dont use it well), I tried to use the gdal_translate to tiled the data but it ddont seems to improve either...

if you have ideas to improve the display.

thanks
Thomas canipel
jasonbeverage jasonbeverage
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Re: large geotiff data file

Hi,

Setting the cache_format simply changes the format that the file is
saved as when it is cached.  You'll need to actually define a cache
for osgEarth to cache the data.

For example:

 <map name="sample" type="globe">
 <image name="test" driver="gdal">
         <url>mapoicp.tif</url>
         <cache_format>png</cache_format>
 </image>

<!--Define a cache that will save tiles to the osgearth_cache directory-->
<cache>
  <path>osgearth_cache</path>
</cache>

 </map>

Also, for imagery, you'll probably be fine keeping the default
tile_size of 256 of changing it to 64.

Thanks!

Jason

On Mon, Feb 8, 2010 at 4:23 PM, tcanipel [via osgEarth]
<[hidden email]> wrote:

> hi, i would like to know how the cache optimization could be used to display
> for example this kind of geotiff file:
>
> http://dl.free.fr/getfile.pl?file=/tJ1JM3HH  : link to the geotiff
> file(571MB)
>
> in order to make it works reproject it : gdalwarp -t_srs epsg:4326
>  mapoic.tif mapoicp.tif  (3800MB)
>
> here is the earth file :
>
> <map name="sample" type="globe">
> <image name="test" driver="gdal">
>         <url>mapoicp.tif</url>
>         <tile_size>64</tile_size>
>         <cache_format>
>             png
>     </cache_format>
> </image>
> </map>
>
> in order to see the data on the globe make the viewpoint here :
>
> osg::ref_ptr<osgEarthUtil::EarthManipulator> manip = new
> osgEarthUtil::EarthManipulator();
> d_viewer.getViewer()->setCameraManipulator(manip);
>
> osgEarthUtil::Viewpoint viewpoint(osg::Vec3d(-73.777, 40.57796, 0), 0, -90,
> 100000);
> manip->setViewpoint(viewpoint, 3);
>
>
> the processor is used a lot when I zoom in or zoom out, but the projection
> is normally already adapt, the <cache format> section dont seems to improve
> (perhaps I dont use it well), I tried to use the gdal_translate to tiled the
> data but it ddont seems to improve either...
>
> if you have ideas to improve the display.
>
> thanks
>
>
> ________________________________
> View message @
> http://n2.nabble.com/large-geotiff-data-file-tp4537181p4537181.html
> To start a new topic under osgEarth, email
> [hidden email]
> To unsubscribe from osgEarth, click here.
>
tkani tkani
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Re: large geotiff data file

thanks fro the answer, I would like to know if the data is reprojected during the osgearth display, is there a way to compute everyting before the display like that it will be fast ?

thanks a lot

thomas
Thomas canipel
gwaldron gwaldron
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Re: large geotiff data file

You can either reproject your source file using gdalwarp, or you can seed the cache using osgearth_seed. See http://osgearth.org/wiki/EarthFileCaching#SeedingtheCache

Glenn
Glenn Waldron / Pelican Mapping