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5

I would first assign an elevation to your road network by creating a new field in your vector data, and populating it with the desired elevation value of your roads. Then, convert it to raster using your existing DEM as the 'master raster' - ie. use the same cell size, extent, snap raster, etc. Now you have your road network in raster form, with the values ...


3

You can create a local CRS with an oblique mercator projection, and transform the data with gdalwarp and gdal_translate into it. See my advice here: Using customized Coordinate System for Archaeological site data This should work with 16-bit or grayscale data the same way. Paletted colours shoud be expanded to RGBA in advance. UPDATE Using QGIS, ...


2

Rather simple method is to write a new world file (.tfw) which contains rotation parameters. You can make such with OpenOffice Calc, for example. If you have a GeoTIFF file which contains reoreferencing info as stored into the image tag you must clear the geotiff tags and create a baseline tiff to start with. It can be done with gdal_translate: ...


2

You're better off mosaicing first. It will save you time and effort to do so. Setting up a batch process in general usually takes a bit more time than firing off a single calculation on a single raster. This is especially true in ArcGIS, whose batch tools aren't always user friendly and are sometimes completely separate geoprocessing tools from the ...


1

It would be best to resample the DEM and then create the slope layer. Take a look at this thread (particularly post 2) from the ESRI forums. You might end up saving yourself some time this way as well. Resampling a DEM will reduce it's size (in terms of disk space), and should allow the slope tool to process in a shorter amount of time.


1

You can do this in R. Here's a script that reads in your DEMs, calculates your stats, plots your results and then writes to csv (if you really want to plot in a spreadsheet). Remember to add your own file locations and you may need to tweak the RMSE, I didn't check that. install.packages("raster") install.packages("e1071") library(raster) library(e1071) # ...


1

If you have a statistically sufficient number of survey data points you could use the elevation values in those points to calculate the RSME using the code below. The survey data table would need to have some existing fields including the surveyed elevation, and the interpolated elevations (from the add surface information tool in the 3d analyst toolbox). ...


1

I'd look at the source data for the DEM. Was it a bunch of points and breaklines you interpolated? How much do you want to decrease the elevation by? Is it a constant value across the surface or only in certain areas? If it's the whole surface, and you have the points in a .CSV file or similar, just open it in Excel, subtract from the elevation field ...


1

As well as Mark Bryant's answer. Also available from the Ordnance Survey Open Data portal is the "Ordnance Survey Meridian2 Map set" This is a vector (Shape file set) with many different layers, however one of the vector layers provided is a 1 meter gridded height point map that can be use to create a tin layer among other things. I've used it previously ...


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OS Terrain 50 is available through the Ordnance Survey OpenData portal. You can find details about OS Terrain 50 at this link: http://www.ordnancesurvey.co.uk/business-and-government/products/terrain-50.html


1

You should look at the geomatics LIDAR group site. registration is required but it is freely available in many part of UK as long as it is for non commercial use. Otherwise, there are of course the SRTM and the ASTER DEM, but the resolution is not as good, respectively 90 and 30 m.


1

The aspect of the question addressed by this answer concerns an efficient way to burn variable-width buffers into a DEM. Although it obviously could be done by extracting each road type, buffering it, and merging the resulting datasets, there's a better way. The immediate objective is to create a 0-1 indicator grid of where to burn the DEM. After that, ...


1

rasterlite_load does have logic to handle imagery other than RGB, but it may not deal with your situation. From the code, the supported combinations are: bits_per_sample == 1 && samples_per_pixel == 1, interpreted as a CCITT 4 fax. bits_per_sample == 8 && samples_per_pixel == 1 && photometric == 3, interpreted as paletted image ...


1

That's very odd because in creating an ESRI floating point raster, Whitebox simply changes the extension of the .tas file (Whitebox) to .flt (ESRI). They share the same basic data format so there is no need to convert anything but the accompanying header file. Given this, I just don't see how the data could be changed in the process. Have you confirmed that ...


1

Maybe your 'Identify from:' choice is set to Visible, Selectable or All layers in the Identify window. Select the Image layer instead, as shown in the screenshot below: EDIT With mosaic datasets, it's not possible to hide the name of the dataset you're identifying (you can actually do it by right-clicking the name of the dataset under Image in the ...


1

For getting DSM or a DTM some countrys have thier own DSM for free, for example in Spain is this page www.cnig.es, and you can download for free the DSM and DTM but only for Spain. Search if your country have similar system.



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