0
votes
1answer
36 views

removing spurious lines in raster before or after vector conversion?

I'm looking for a feature/function in either python opencv/ndimage/gdal/etc. or qgis/saga/grass that will help clean up a skeletonized image that I'd like to vectorize into a shapefile of ...
0
votes
1answer
32 views

Trouble with r.out.gdal in GRASS GIS

I'm processing some landsat 8 files. I'm using this scene LC82260982013325LGN00 and I have to apply i.landsat.toar and export the result as a GTiff. However when I use r.out.gdal it takes a very long ...
0
votes
0answers
143 views

libgdal1 and libgdal1h conflict

I am on Ubuntu 14.04. When I am installing PostGIS-2.1, it's asking for libgdal1 library. But when I am installing libgdal1, it's removing grass and gdal. Can someone please guide me how to install ...
1
vote
1answer
64 views

List the projection & datum of all the files in a folder

In QGIS/GRASS, is it possible to list the projection details of all the shp,tab,dxf files in a folder ? We are having 100 - 150 files in too many folders. We would like to create a table of Proj ...
1
vote
2answers
153 views

How to create a time series with a NetCDF raster from Ensembles E-OBS using GDAL, R, GRASS GIS or SAGA GIS

I downloaded a NetCDF file that contains daily precipitation values from 1-1-1950 to 30-6-2013. The raster has 23191 bands. http://eca.knmi.nl/download/ensembles/download.php My goal is to analyze ...
0
votes
0answers
91 views

No data appears when using gdal_calc.py but source had data values

I'm in the process of calculating topographic exposure using a mix of GDAL, grass, R and python in Windows. I need to process a very large tiff file using the following calculation: ...
4
votes
2answers
211 views

Merge two rasters with no data value

I have two rasters: Raster A and B. Raster A has has only values of 0. The white area in Raster B are No Data values. I want to merge them to one raster (Raster C). So basically I want all pixels in ...
0
votes
0answers
69 views

gdalbuildvrt ------— Problems with binary rasters used by grass

r.in.gdal is used for importing tif images in grass environment and they were changed to binary by default. I am trying to make a stack from them but unfortunately grass does not see my rasters ...
2
votes
1answer
162 views

Installing QGIS 2.0 with the newest gdal and geos libraries

I want to install QGIS 2.0 on Ubuntu 12.04 LTS. I followed these steps until the final installation command. Before I compiled gdal 1.10, geos 3.4.2 and grass 6.4.3 on my own. In the synaptic ...
0
votes
1answer
50 views

How to import r.in.gdal from WCS (only region extent)

Can I import WCS-Data only for the current region by r.in.gdal? I tried to import raster data from my WCS into GRASS GIS, using r.in.gdal as proposed in ...
1
vote
1answer
324 views

What is the best way to ortho-rectificate image from the plane?

I am very new in GIS and I am trying to ortho-rectificate my images. But after putting it on the map I see that results are not precise. We have images taken from the airplane, it's longitude, ...
1
vote
2answers
364 views

How to remove z & m coordinates from shapes with QGIS? (Or arcgis, grass, gdal, Python…)

I've recently received some parcel data in shapefile format that has z & m coordinates (all = 0.0). The WKT for a typical parcel looks like this: "MULTIPOLYGON (((2672464.560700002 ...
1
vote
1answer
117 views

How to duplicate this QGIS workflow with gdal/GRASS? (reproject and crop a raster)?

I have a number of rasters (rgb images) that I want to re-project and crop. I have established a workflow for doing this in QGIS, but I'd like to do it using gdal modules, because the output is being ...
3
votes
2answers
469 views

How to set output resolution for gdalwarp to that of source file?

I have a large raster, which I want to re-project and crop for a new location that I'm creating in GRASS. I seem to have gotten the re-projection and cropping right with this call to gdalwarp: ...
0
votes
1answer
72 views

Where do I find the code for gd_calc.py?

I need to create a raster that is the average of a large set of other rasters (many thousands). I've learned from another question that the script gd_calc.py can do a limited version of this, limited ...
0
votes
2answers
156 views

How to average a set of n rasters using gdal or other GRASS module? [duplicate]

I need to average a set of n rasters using gdal or some other GRASS module. What command exists for this purpose?
1
vote
0answers
796 views

How do I change from lat/long to a metric coordinate system in GRASS?

Yes, it's yet another transformation question. I am working with ASTER DEM data, which is LatLong WGS84. I want to process the DEM map into an STL file for use in a CFD simulation. The script I am ...
0
votes
2answers
176 views

Handling MODIS NoData cells with gdalwarp

I'm using the gdalwarp tool to convert MODIS .hdf into GeoTiff files. I want to set the value of the nodata cells so that when I import the .tif image into Grass there is no black edge. I'm using the ...
1
vote
1answer
266 views

Rasterize vector with gdal

"I would like to calculate the Euclidian distance from a residence to a public service of interest e.g. the distance from a residence to a green space (as the crow flies) in QGIS. After browsing the ...
4
votes
1answer
164 views

Programmatic raster-vector calculation

I currently use GRASS' r.mapcalc to find the difference between vector and raster data using a loop and temporary files and layers. Is it possible to do the core calculation between raster with a ...
3
votes
1answer
445 views

Is it possible to produce a decent looking shaded-relief map at 50K-scale-or-larger using SRTM3 DEM?

I'm trying to make a decent-looking shaded-relief map of a particular area in 50K-scale-or-larger using open-source tools. The best (and free) option I have for DEM data for that area right now is the ...
3
votes
1answer
631 views

Cell calculations; QGIS,GRASS,GDAL,SAGA

I recently asked a question about trying to calculate the slope over distance (manually) using QGIS, but then I came up with another way of solving the problem, but I would have to get some help for ...
1
vote
0answers
283 views

gdal-grass plugin for gdal 1.8 [closed]

I'm facing a big issue...i moved from the ubuntugis version of grass to the svn one. I managed to compile the svn (releasebranche6.4) version nicely but i can't download the gdal-grass plugin for ...
6
votes
2answers
694 views

What's a good toolchain to reproject some PNGs in plate carre to UTM?

I have some PNGs produced from Canadian DEM data. They're 1201px by 1201px heightmaps. Each one represents one quarter of a degree latitude and one quarter of a degree longitude. But I want to work ...
5
votes
1answer
592 views

What is north-up projection?

How do I know what projection to use for north-up or 0 rotation? I have a gtiff (ND83-nf) that gives me the error when importing to Grass. Should I re-project or recreate the image with the rotation ...