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Given a raster layer (e.g 10km resolution) and a vector layer with many features (with finer resolution), is it possible to redistribute the value of each raster pixel in an attribute among the underlying polygons, so that the sum of that attribute in the underlying features is equal to the overlaying pixel value?

If so, can this be done either homogeneously across underlying features, or based on a weight given by another attribute in the polygon layer?

QGIS-based solutions are favoured.

Jackk
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in QGIS you can use the Processing Tool "Zonal Statistic" for that task:

enter image description here

eurojam
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    No, I think you missed the point. Zonal statistics can give me the sum within polygon. So in case of multiple polygons underlying a single raster pixel, it would likely repeat the same total value in each polygon. While I would like the value to be redistributed across polygons. – Jackk May 22 '19 at 08:36
  • ok, I missed that. – eurojam May 22 '19 at 08:39
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    There have been discussion about distributing the values from polygons across overlapping polygons based on area of overlap. If you polygonize the raster you could then apply polygon value-redistribution techniques. – csk May 22 '19 at 20:46
  • for example: https://gis.stackexchange.com/questions/214893/calculating-proportional-area-of-polygon-within-another-layers-polygon-using-qg, https://gis.stackexchange.com/questions/81159/calculate-area-proportional – csk May 22 '19 at 20:48
  • @csk's first example seems to be what you are looking to do using the union tool: https://gis.stackexchange.com/questions/214893/calculating-proportional-area-of-polygon-within-another-layers-polygon-using-qg – Erich Purpur May 22 '19 at 21:19