Re: Decimated and windowed read in rasterio


Thanks to @Sean Gillies.

Posting here the solution I also posted on (

Maybe it would be useful for others in search of a solution for a similar problem.

Basically, it is not possible to simultaneously make a windowed AND decimated read, so the answer to my question is NO.

However, there is an undocumented (AFAIK) parameter called overview_level which can be passed to

This parameter takes the 0-based index of an overview level. So, assuming overviews are present in a source raster, one can do

src =, overview_level=0)

to create a Rasterio dataset from the first level of overview of source raster.

Then, simply do a windowed read in the common format:

for ji, src_window in src.block_windows(1):
    arr =, window=src_window)

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