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I am working on large raster in QGIS and I am doing various simulations on them. There is one thing that I don't understand.
I have a large raster (111 072 kb) that I clip to only have the values I'm interested in. The new raster only retains 3% of the values from the original raster. When I look at the values in QGIS, everything seems right. The values that I clipped have the good values and outside it's only a No data area (which is what I want). However, the clipped raster is still pretty heavy for the amount of value it has (85 596 kb), so approximately 77% of the size of the original raster.
Why is the clipped raster still so heavy and not more or less 3% of the original file size?