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I have a raster which I want to cut. A second raster smaller, should be exactly the part where I want to cut the first layer (so I cut the same size as raster 2).

The idea is that raster 2 become the mask for the cut. How can I do this?

Joseph
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Magus
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3 Answers3

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You could convert "raster 2" to a polygon (Raster > Conversion > polygonize). Then run the Clipper tool (Raster > Extraction > Clipper...) and use the polygonized "raster 2" as the mask layer.

Joseph
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  • thank you alot it worked. If the clipper becomes 4 times bigger? the clipping times to extract the first raster is muuuuuch longer is that normal? – Magus Oct 06 '15 at 08:55
  • @Magus - Glad it worked! I think one of the main reasons which affect the length of processing time is the size of the rasters in the first place. So if the mask is larger, more processing needs to be done by the clipper :) – Joseph Oct 06 '15 at 09:55
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You can use Vector -> Research Tools -> Polygon from Layer Extent on the smaller raster.

In a second step, use this polygon as a clip mask for the second raster with Raster -> Extraction -> Clipper.

AndreJ
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  • I find this method the easiest/quickest. But it is now: Vector -> Research Tools -> Extract Layer Extent – Beardsley Feb 01 '21 at 21:19
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Try using "raster calculator": Deduct raster 2 from raster 1 and then change zero values to null values.

Hairy
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Damian
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