Crunching overviews

Continuing my tale about loading big raster datasets into PostGIS database with WKT Raster extension, I’d like to post an update about experience with processing overviews.

For testing purposes, I built excessive number of overviews for japan.tif dataset using gdaladdo utility:

$ gdaladdo -r average japan.tif 2 4 8 16 32 64 128

The command above produced 7 overviews with the following dimensions:

$ gdalinfo japan_2_4_8_16_32_128.tif | grep -m 1 Ov
Overviews: 7000x7000, 3500x3500, 1750x1750, 875x875, 438x438, 219x219, 110x110

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