[mapserver-users] Re: Raster Strategies Examples

[Frank Warmerdam]

Edi.Karadumi wrote:
> Sorry to bother again, when i use gdal_merge.py the part -ps 160 160, thats
> the pixel dimension and i get an image 1kb. The pixel size of the original
> file is 0.08 meters. So i think i should use 0.08x32 in the gdal_merge.py
> command? 

Edi,

If the original resolution is 8cm then the 1/32nd overview should indeed
have a pixel size of 0.08x32 or 2.56m.

 > And how many tiles should i merge together? Now i have 2T images
 > and 2000Gb/32 = 62Gb the rezult image. Should i merge them all together and
 > than recreate tiles? Even if i had 1200gb, 1200/32=37.5gb for an image not
 > 1gb. That is still an image size that cant be handled

Note that the 1/32nd overview is reduced by a factor of 32 in x and y
so overall it will be original_size/(32*32).  So 2TB would reduce to
about 1.95GB.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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