The Shuttle Radar Topography Mission (SRTM) obtained elevation data on a near-global scale to generate the most complete high-resolution digital topographic database of Earth. SRTM consisted of a specially modified radar system that flew onboard the Space Shuttle Endeavour during an 11-day mission ...
3
votes
1answer
37 views
What is the difference between TIFF and ArcASCII file?
what is the difference between the ArcInfo ASCII format and the geotiff file format when downloading the SRTM data.
I downloaded the tiles (21) for the Tibetan Plateau and imported thme into ARCMAP ...
3
votes
2answers
108 views
Hillshade for 30m NED at continental scale
I'm new to terrain analysis. I have a 30m NED DEM (.tif) for the conterminous US. I would like to generate a nice looking hillshade for the US, but it looks bad - as in pixelated and rough (See ...
1
vote
0answers
52 views
Conversion from CGIAR GEOTIFFs to SRTM3 like HGTs
Im writing a C program for querying height information from SRTM data. Since reading directly GeoTIFF format is tough job, I decided to load HGT format, which serves great for the purpose.
Since ...
1
vote
2answers
159 views
Using SRTM DEM files in ArcMap for shaded relief
I would like to create a nice shaded relief for France using SRTM3 data. Most of the threads on the subject are from awhile ago, when ArcMap was not able to import these without changing the file ...
1
vote
0answers
58 views
How to convert DTED Level 1 into SRTM DTED
We have a GIS tool that handles only SRTM DTED level 1 terrain files. SRTM level 1 terrain files are limited to 60 deg lat. So I need to fill up the gap from 60 lat up to 90 deg lat.
I have DTED ...
2
votes
3answers
2k views
How to extract elevation from .HGT file?
I want to asign a specific long/lat position on a map the elevation from SRTM3 data files, but have no idea how to find the specific value. So I want some example of how I can find in N50E14.hgt ...
2
votes
1answer
216 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 ...
2
votes
0answers
204 views
How to read Geotiff tags and pixel per pixel values using GDAL C#
I'm new here and I'm new at programing with GDAL C#.
My question is how I can get the value of SRTM GEOTIFF pixel to compare with it's neighbors, and how can I get the values of Geotiff tags.
1
vote
1answer
222 views
Using SRTM data, how to get the coordinates of the peaks visible from a location?
Using SRTM data and a coordinate-altitude database of the peaks, I want to get the coordinates of the visible peaks from my location. I want to make an application similar to this.
How is this ...
1
vote
1answer
116 views
How can I recalculate an attribute based on overlap with another layer?
I have 2 layers: The first one is a point Layer (converted from SRTM) with height information. The second one is a polygon layer (shows the forest).
I want to reduce the height value - let's say ...
4
votes
0answers
122 views
How to stop gdalwarp creating world-spanning outputs near the dateline?
I'm using gdalwarp to manipulate SRTM tiles near the the dateline (i.e. 180°, aka the antimeridian). SRTM tiles have a very slight (1/2 pixel) overlap with the meridian. You can see this using ...
1
vote
1answer
261 views
Using Latitude and Longitude with SRTM3 DEM file
I am new to working with DEM files but have a need to be able to work with SRTM3 DEM files to calculate elevation given a Lat,lon coordinates.
I understand from reading the documentation that the ...
4
votes
4answers
302 views
Does a value in srtm dem file refer to the center or corner of a cell?
I'm working with srtm dem files. They are ascii text files containing a table/grid of elevation values. At the top of the file is some metadata to locate the grid in lat/lon:
xllcorner ...
3
votes
1answer
369 views
Correct ASTER with SRTM or Topographic Map
I have a problem with my DEM again. I decided to use ASTER GDEM2 (for different reasons). ASTER GDEM2 have its problems, I know, and I dont want to discuss that again. I have to use it, because SRTM ...
2
votes
1answer
415 views
Export SRTM30 Dem file as 3d
i have downloaded some SRTM Dem files here: http://dds.cr.usgs.gov/srtm/version2_1/SRTM30//srtm30
They are from the USGS site.
I would like to export them as 3d.
I have ran through a few ...
2
votes
2answers
827 views
How to use SRTM30 Plus data with QGIS or other GIS tool?
I am trying to access the new Bathymetry data published here:
http://topex.ucsd.edu/WWW_html/srtm30_plus.html
Is there a way QGIS or similar tool can read these files. Nothing seems to be working, ...
0
votes
1answer
1k views
How can I convert SRTM data to DEM or DTED?
i am working on a project which is not commercial and i need some digital elevation data for visualization. in net i have found a link and i have downloaded .asc data from following link..
SRTM Data ...
3
votes
1answer
794 views
How to read GeoTIFF using PHP?
My current pet project involves creating a web service that uses the CGIAR SRTM worldwide elevation data set. Each request to the service will query for elevation data from a small geographic area.
...
12
votes
5answers
2k views
How to get an elevation profile for a gps track?
I'd like to get a reasonably accurate elevation profile for a track recorded with a GPS (which often has very unreliable altitude data and occasionally none at all, depending on the model.)
Does ...
2
votes
2answers
1k views
Converting ASCII grid/NTF to SRTM/DEM
I want to use the Ordnance Survey Land-Form Panorama product in some software called Maperitive, which can read custom SRTM DEM files.
The data is provided in the following formats:
DXF [Contours]
...
14
votes
7answers
3k views
Are there open access terrain tiles with a permissive license like OSM?
Are there open access terrain pyramidal map tiles with a permissive usage license like OpenStreetMap's? I'm building aviation-related maps with Polymaps and need a good raster basemap. The Google ...
0
votes
1answer
293 views
How to transform a DEM to a cartesian coordinate system?
I am using the script r.inund.fluv. I run the script with all the required parameters and it produced a lot or errors.
I emailed the author of the script and he said that
"I think you are not ...
3
votes
2answers
167 views
How to make the arrows in d.rast.arrow GRASS script visible?
I'm trying to create a Flow or directional raster map (with arrows) from an SRTM elevation map that I downloaded from CGIAR.
I already created an aspectMap to be used for the d.rast.arrow. I used ...
4
votes
3answers
566 views
How to get the elevation of the areas in a raster file from SRTM?
I have an SRTM elevation map. How do I get the elevation of each point in the map? I am using GRASS. Is there a GRASS script to do such?
2
votes
2answers
493 views
How to query data from a vector map (shapefile)?
We want to obtain the specific place of the boundaries of a shapefile. We want to be able to get the points of each polygon corresponding to a specific place in order to use these data in an ...
7
votes
4answers
2k views
Downloading SRTM data
Is there an easy way to mass download SRTM data? The data is published for download here, but it's sliced into thousands of small files, and I don't see an FTP option for more efficient ...
3
votes
1answer
369 views
Where can I find USGS SRTM 3 index grid or what procedure should I employ to select tiles?
I would like to download all USGS SRTM 3 tiles for Ontario, Canada from the USGS site: http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/North_America/
Where can I obtain the index that will assist me in ...
