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<div>Hello all,</div>
<div>I have a grid on a 1m resolution with a tilesize of 8000x8000.</div>
<div>To speed up the rendering process I have created overviews with gdaladdo, the result you can see in the gdalinfo below.</div>
<div>The default blocksize is 512x512.</div>
<div>My questing handles the combination of blocksize and overviews. The blocksize is 512x512 and the lowest resolution of the overview generates a block of 63x63. Are the lower resolution overviews usefull? I suppose it is only usefull to create overviews
until 500x500 if I have a blocksize of 512x512. Am I right?</div>
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<div><em style="font-size: 10pt;">[root@-appl bin]# gdalinfo /dsg/data/2d008/01/01/box_524_5689_hist.tiff</em></div>
<div><em style="font-size: 10pt;">Driver: GTiff/GeoTIFF</em></div>
<div><em style="font-size: 10pt;">Files: /dsg/data/2008/01/01/box_524_5689_hist.tiff</em></div>
<div><em style="font-size: 10pt;">Size is 8000, 8000</em></div>
<div><em style="font-size: 10pt;">Coordinate System is:</em></div>
<div><em style="font-size: 10pt;">PROJCS["ETRS89 / UTM zone 31N",</em></div>
<div><em style="font-size: 10pt;"> GEOGCS["ETRS89",</em></div>
<div><em style="font-size: 10pt;"> DATUM["European_Terrestrial_Reference_System_1989",</em></div>
<div><em style="font-size: 10pt;"> SPHEROID["GRS 1980",6378137,298.2572221010002,</em></div>
<div><em style="font-size: 10pt;"> AUTHORITY["EPSG","7019"]],</em></div>
<div><em style="font-size: 10pt;"> TOWGS84[0,0,0,0,0,0,0],</em></div>
<div><em style="font-size: 10pt;"> AUTHORITY["EPSG","6258"]],</em></div>
<div><em style="font-size: 10pt;"> PRIMEM["Greenwich",0],</em></div>
<div><em style="font-size: 10pt;"> UNIT["degree",0.0174532925199433],</em></div>
<div><em style="font-size: 10pt;"> AUTHORITY["EPSG","4258"]],</em></div>
<div><em style="font-size: 10pt;"> PROJECTION["Transverse_Mercator"],</em></div>
<div><em style="font-size: 10pt;"> PARAMETER["latitude_of_origin",0],</em></div>
<div><em style="font-size: 10pt;"> PARAMETER["central_meridian",3],</em></div>
<div><em style="font-size: 10pt;"> PARAMETER["scale_factor",0.9996],</em></div>
<div><em style="font-size: 10pt;"> PARAMETER["false_easting",500000],</em></div>
<div><em style="font-size: 10pt;"> PARAMETER["false_northing",0],</em></div>
<div><em style="font-size: 10pt;"> UNIT["metre",1,</em></div>
<div><em style="font-size: 10pt;"> AUTHORITY["EPSG","9001"]],</em></div>
<div><em style="font-size: 10pt;"> AUTHORITY["EPSG","25831"]]</em></div>
<div><em style="font-size: 10pt;">Origin = (524000.000000000000000,5696999.000000000000000)</em></div>
<div><em style="font-size: 10pt;">Pixel Size = (1.000000000000000,-1.000000000000000)</em></div>
<div><em style="font-size: 10pt;">Metadata:</em></div>
<div><em style="font-size: 10pt;"> AREA_OR_POINT=Area</em></div>
<div><em style="font-size: 10pt;">Image Structure Metadata:</em></div>
<div><em style="font-size: 10pt;"> COMPRESSION=LZW</em></div>
<div><em style="font-size: 10pt;"> INTERLEAVE=BAND</em></div>
<div><em style="font-size: 10pt;">Corner Coordinates:</em></div>
<div><em style="font-size: 10pt;">Upper Left ( 524000.000, 5696999.000) ( 3d20'42.66"E, 51d25'25.28"N)</em></div>
<div><em style="font-size: 10pt;">Lower Left ( 524000.000, 5688999.000) ( 3d20'40.71"E, 51d21' 6.32"N)</em></div>
<div><em style="font-size: 10pt;">Upper Right ( 532000.000, 5696999.000) ( 3d27'36.86"E, 51d25'23.86"N)</em></div>
<div><em style="font-size: 10pt;">Lower Right ( 532000.000, 5688999.000) ( 3d27'34.27"E, 51d21' 4.90"N)</em></div>
<div><em style="font-size: 10pt;">Center ( 528000.000, 5692999.000) ( 3d24' 8.62"E, 51d23'15.14"N)</em></div>
<div><em style="font-size: 10pt;">Band 1 Block=512x512 Type=Int16, ColorInterp=Gray</em></div>
<div><em style="font-size: 10pt;"> NoData Value=10000</em></div>
<div><em style="font-size: 10pt;"> Overviews: 4000x4000, 2000x2000, 1000x1000, 500x500, 250x250, 125x125, 63x63</em><br>
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