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qgis_slope [2021/02/20 09:50] – created bushwalkingqgis_slope [2023/03/05 11:40] (current) bushwalking
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 {{::qgis_styling_slope.png?nolink|}} {{::qgis_styling_slope.png?nolink|}}
 +
 +===== Compressing large slope files =====
 +
 +Because the Slope layer is just a style file on top of a (possibly very large) DEM, it can take up a lot of space when it comes to saving the files for use in [[qgis_qfield|QField]].
 +
 +Converting the DEM to a much simpler raster can save large amounts of space, and make using the data in a mobile device much more responsive.
 +
 +From the Processing Toolbox, use the Raster Calculator with the DEM (or depressionless DEM) as Input A, the output type as Int32, and the following formula in the Calculation box:
 +
 +''(A>40)*(A<=50)*1 + (A>50)*(A<=60)*2 + (A>60)*(A<=70)*3 + (A>70)*4''
 +
 +The resulting calculated layer can be as little as 10% of the size of the original. 
 +
 +You need a slightly different {{ :slope_cliffline_category.qml |style file}} to style this layer, but it should look identical in use.
qgis_slope.txt · Last modified: 2023/03/05 11:40 by bushwalking

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