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I need third party image tiles (probably world imagery) under sweref99_1800 projection and coordinate system (EPSG 3008). I found this link http://www.naturalearthdata.com/downloads/10m-raster-data/10m-cross-blend-hypso/ for downloading world imagery but it is in spherical mercator projection (EPSG 4326). Is there any link from where we can download world imagery in sweref99_1800 format.

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is it possible to change the projection and coordinate system of image tiles (world imagery) from spherical mercator(EPSG 4326) to swereff99_1800 format (EPSG 3008) ?

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Note 4326 is not a spherical mercator projection, it's unprojected lat/lon (or lon/lat). –  iant Mar 14 '12 at 14:49
    
Spherical mercator is defined as EPSG:3857 (and some other too). –  Andre Joost Dec 12 '13 at 16:16
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2 Answers

up vote 1 down vote accepted

From spatialreference.org I can see that you'll need to clip your image to 10.5700, 55.2000, 24.1800, 69.1000 first then warp it. (see the faq)

gdalwarp -projwin 10.5700 69.1000 24.1800 55.2000 -s_srs EPSG:4326 -t_srs EPSG:3008 yourfile.tif outfile.tif
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Thanks for this useful information. As i understand, -projwin will extract a small window (a part of imagery)with 10.57, 55.200, 24.180, 69.100 bounding box from world imagery and then will change the projection/coordinate system to 3008. Am i write in my understanding ? –  user1899 Mar 15 '12 at 12:38
    
that is correct –  iant Mar 15 '12 at 13:10
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What you want is to project the image. You can do so by installing the GDAL package and using gdalwarp.

In your case, you would run this command

gdalwarp -s_srs EPSG:4326 -t_srs EPSG:3008 yourfile.tif outfile.tif

You can play around with the various resampling methods (bilinear, cubic, cubicspline, lanczos) to see which produces the best results.

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This will not work with a worldwide source file, because SWEREF like every transverse mercator projection will produce artefacts outside its area of definition. –  Andre Joost Dec 12 '13 at 16:15
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