ST_CreateOverview — Create an reduced resolution version of a given raster coverage.
regclass
ST_CreateOverview
(
regclass
tab
, name
col
, int
factor
, text
algo='NearestNeighbor'
)
;
Create an overview table with resampled tiles from the source table.
Output tiles will have the same size of input tiles and cover the same
spatial extent with a lower resolution (pixel size will be
1/
factor
of the original in both directions).
The overview table will be made available in the
raster_overviews
catalog and will have raster
constraints enforced.
Algorithm options are: 'NearestNeighbor', 'Bilinear', 'Cubic', 'CubicSpline', and 'Lanczos'. Refer to: GDAL Warp resampling methods for more details.
Availability: 2.2.0
Output to generally better quality but slower to product format
SELECT ST_CreateOverview('mydata.mytable'::regclass, 'rast', 2, 'Lanczos');
Output to faster to process default nearest neighbor
SELECT ST_CreateOverview('mydata.mytable'::regclass, 'rast', 2);