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the gdal driver (used by QGIS) supports eight, sixteen and thirty-two bit integer raster data types as well as 32 bit floating points for conversion to bil. based on the error message, your tiff data seems to be 64 bit (double) type, which is not supported. You could try to change the pixel depth before converting to .bil


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A solution to this is discussed on the ESRI forum here: Every planar surface has a simple formula, Jesse, in the form (something)*x + (something else)*y + (constant). In the Raster Calculator, x is $$XMap and y is $$YMap. The trick is figuring out the coefficients. Often you want to specify a plane in terms of its slope (s), aspect (a), ...


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Constructing lidar DEMs from unclassified point clouds with: MCC-LiDAR using the Multiscale Curvature Classification (MCC) algorithm. MCC-LIDAR is a command-line tool for processing discrete-return LIDAR data in forested environments" (Evans & Hudak, 2007). Workflow illustration (gross cloud --> ground returns classified --> bare-earth DEM): ...


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From a theoretical point of view depression filling only has one solution, although there can be numerous ways of coming to that solution, which is why there are so many different depression filling algorithms. Therefore, theoretically a DEM that is filled with either the Planchon and Darboux or the Wang and Liu, or any of the other depression filling ...


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I will attempt to answer my own question - dun dun dun. I used SAGA GIS to examine the differences in filled watersheds using their Planchon and Darboux (PD) based filling tool ( and their Wang and Liu (WL) based filling tool for 6 different watersheds. (Here I only show case two sets of results - they were similar across all 6 watersheds) I say "based", ...


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Use Get Raster Properties, specifically the MINIMUM and MAXIMUM values. In theory, this code should make a temporary raster layer using the display extent -- although I have not tested it, and am not sure whether it will work -- and then the raster properties tool will apply to only the raster currently shown in the display. import arcpy arcpy.env.extent ...


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Not sure why, but if you rename your layer to "p", it works for me: <OGRVRTDataSource> <OGRVRTLayer name="p"> <SrcDataSource>p.csv</SrcDataSource> <GeometryType>wkbPoint</GeometryType> <GeometryField encoding="PointFromColumns" x="field_1" y="field_2" z="field_3"/> </OGRVRTLayer> ...


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After I checked my data source and used different GIS Tools (under them 3DEM a really nice DEM Viever, that gave me the right heights), I came to the conclusion that the grayband values, that are shown by QGIS, when you drag your DEMs in it, are simply wrong and aren't the height values. Both SRTM and ASTER DEMs store (in general) their data in meter. If ...


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Attempt to answer my own question: The cause of striping in the examples I provided are entirely due my workflow, not any legacy issue with how the data was originally assembled or mosaiced together. The DEMs I was dealing with were all generated from newer techniques, as evidenced by this map: The two methods that cover the areas I was working with are ...


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There are a few posts on the possible source of the striping that are too long to copy here and post, for example https://geonet.esri.com/message/248734?sr=search&searchId=8194652f-cac8-4737-93a2-c5dccdeb29ff&searchIndex=5#248734 http://ned.usgs.gov/about.html http://www.ctmap.com/assets/pdfprojects/destripe.pdf Some of the issues are associated ...


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Try using this, http://resources.arcgis.com/en/help/main/10.1/index.html#//0017000000m3000000 Turn the current data frame extent to a polygon via this extent = inFeature.extent extentPoly = drive + "\\NCT_GIS\\Projects\\Temp\\extentPoly.shp" # Array to hold points array = arcpy.Array() # Create the bounding box ...


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As others have suggested, reproject to something with a linear measurement. But be sure to use BILINEAR interpolation (not the default of Nearest Neighbor). This should avoid the grid-like artifacts that stem from resampling patterns (you may notice that if you do multiple reprojections and change the cell size among them, you can get the cross-hatching to ...



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