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SINTEF / Geomaker

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Feature request: "fill missing data with XXX" in export window #42

Open VikingScientist opened 4 years ago

VikingScientist commented 4 years ago

This is especially annoying when considering islands as large sea-areas surrounding the island typically are omitted from the data. The geoTIFF approach is to set this to negative infinity or something of the sort. I would like an option in the export window to fill all missing data points with a given value. For the island scenario above, this would typically be sea-level (z=0), but I'm sure there are cases where you want to fill it with something else than sealevel.

VikingScientist commented 4 years ago

And now I see that this is exactly what the "zero at sea level" checkbox is suppose to do, however it seems to only work for the thumbnails, or at least it fails when exporting to geotiff format. I'm happy with having a checkbox solution (even more happy that it defaults to checked), but I'm suspecting this is a bug in the geotiff-export functionality, of which I'm not happy with.

TheBB commented 4 years ago

No actually the zero at sea level checkbox was supposed to be for inland areas where the lowest elevation may not be zero. If you uncheck it then the zero level in the output will be whatever the lowest elevation in the input is, not necessarily exactly at sea level.

The negative infinity (which is actually more like -32000 or thereabouts) actually comes from kartverket. If you request DTM1 data from areas where it's not available, for example, that's how missing data is denoted. I'd call it a bug but it's really just a case of not sufficiently sanitized data.