YunoSeeMe

This is a collection of tools to compute elevation profiles between two points.

It makes an extensive use of GDAL to handle DEM files to get elevation data from.

Setup

Clone this repository
Check the requirements (python >= 2.7 and the libraries listed bellow)
Download a DEM (see DEM maps and Tests)

Run

Raw data from the command line

./profile_output.py lat1 long1 lat2 long2 -d path/to/dem/file

Look for the generated profile.json file

Generate a PNG picture of a profile

./profile_output.py lat1 long1 lat2 long2 -d path/to/dem/file -of png

Look for the generated profile.png file

Start a webserver serving both (JSON and PNG)

./profile_server.py -d path/to/dem/file

Browse to http://localhost:8080/profile/json?lat1=lat1&long1=long1&lat2=lat2&long2=long2 for JSON
Browse to http://localhost:8080/profile/png?lat1=lat1&long1=long1&lat2=lat2&long2=long2 for PNG

Following parameters can be used :

lat1: latitude of the first point
long1: longitude of the first point
lat2: latitude of the second point
long2: longitude of the second point
og1: line of sight offset (in meters) from the ground level of the first point
os1: line of sight offset (in meters) from the sea level of the first point
og2: line of sight offset (in meters) from the ground level of the second point
os2: line of sight offset (in meters) from the sea level of the second point

Dependencies

It needs the following python libraries to work correctly:

NumPy (1.9.2)
GDAL (1.11.2 <- not the last one)
CherryPy (3.8.0) (to run the web server)
pytest (2.7.2) (to run tests)
matplotlib (1.4.3)

These libraries can be obtained by pip or easy_install. They may need two following system packages to work correctly:

GDAL headers (gdal-devel), libs (libgdal1) and python bindings (python-gdal), main binaries can be useful too (gdal)
NumPy headers (python-numpy-devel) and libs (python-numpy)
PROJ headers (libproj-devel) and libs (libproj0 and libproj9)

See https://trac.osgeo.org/gdal/wiki/DownloadingGdalBinaries to know how to get GDAL.

virtualenv

A virtualenv can be used (in fact, I use one). Consider using the --no-site-packages option.

Linux

On Linux based systems, GDAL python module install may need to have the headers location correctly specified:

export CPLUS_INCLUDE_PATH=/usr/include/gdal
export C_INCLUDE_PATH=/usr/include/gdal

MacOS X

The MacOS X link (http://www.kyngchaos.com/software:frameworks) contains a package that bundles all the GDAL requirements (GDAL Complete Framework) except NumPy that should already be installed in the system.

The gdal python library may not work in a virtualenv, in that case, you can copy the library included in the GDAL Framework using the following command inside your environment:

cp -R /Library/Frameworks/GDAL.framework/Versions/1.11/Python/2.7/site-packages/* <env>/lib/python2.7/site-packages

DEM maps

The elevation related tools need a data elevation model (DEM) to work correctly.

These DEMs are known to work:

Digital Elevation Model over Europe (EU-DEM)

The EU-DEM dataset is a realisation of the Copernicus programme, managed by the European Commission, DG Enterprise and Industry.

The EU-DEM is a hybrid product based on SRTM and ASTER GDEM data fused by a weighted averaging approach and it has been generated as a contiguous dataset divided into 1 degree by 1 degree tiles, corresponding to the SRTM naming convention.

http://www.eea.europa.eu/data-and-maps/data/eu-dem#tab-metadata

Shuttle Radar Topography Mission (SRTM)

SRTM was a joint project of NASA, the German and Italian space agencies, and the National Geospatial-Intelligence Agency.

It was managed by NASA's Jet Propulsion Laboratory, Pasadena, California, for NASA's Science Mission Directorate, Washington, D.C.

SRTM flew aboard the Space Shuttle Endeavour in February 2000, mapping Earth's topography between 56 degrees south and 60 degrees north of the equator

http://www.jpl.nasa.gov/news/news.php?release=2014-321

Tests

Tests use the following DEM: _dem/N43E001.hgt from SRTM.

It was downloaded from the following link: http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/Eurasia/N43E001.hgt.zip

It is also the default DEM when running the tools (specified in the config.ini file). It can be changed either in the config file or by command line.

Known limitations

Only works with 1 DEM file, if the path is among 2 or more DEMs, it won't work

TODO

More tests (there are currently not enough)
Add some scoring about the probable visibility between two elevated points

Q&A

Q: Why not use existing tools or websites such as heywhatsthat, Google Maps or OpenStreetMap?

A: I wanted to propose an alternative that could be completely independent. It could be run on a notebook without an Internet connection if needed.

Q: Why python?

A: When I searched for elevation profile dev topics on the Internet, I saw a lot of source code written in python, so I choose it to have more support in case of problems. Moreover it was a good occasion to learn python because I'm a newb.

Q: What is that name?!? (YunoSeeMe)

A: It comes from a popular meme (Y U NO...), the letter case is similar to YunoHost. It is the question that these tools try to answer => Why don't you se me? In fact the real question answered is: How well do you see me?

License

All files provided here are licensed under the Simplified BSD "2-Clause" License. See the LICENSE file for the complete copyright notice.

superbob/YunoSeeMe