celutz

Celutz

Visualize a collection of panoramic photos.

Celutz allows you to upload/share/visualize/reference panoramic photos. It has been created for evaluating lines-of-sight for radio networks.

The first version of this tool was written in PHP/js by Marc Souviron, Victor Pongnian, and subsequent work by Jocelyn Delalande. The project originated at tetaneutral.net, a non-profit radio ISP in France.

This is version 2 of celutz, with a backend rewritten in Django. For more information, see CHANGELOG.md.

Features

• upload panoramas to a web server (i.e: made with Hugin);
• visualize, pan and zoom panoramas, as if you were on site;
• georeference panoramas : set GPS coordinates and elevation of known reference points, and calibrate orientation of panoramas by visually pointing at these reference points;
• visualize a point by its lat/lon/altitude on your panorama;
• see other panoramas locations to evaluate the lines-of-sight.

Getting started: basic usage of celutz

Add reference points

If this is a new installation, you first need to add reference points to the database.

Reference points are needed to visually calibrate panoramic photos: they can be high buildings, clock towers, radio towers, or even natural features such as mountains. In short, reference points should be easily and accurately recognisable when seen on a picture.

To add new reference points, go to the Django admin, for instance at http://localhost:8000/admin/panorama/referencepoint.

You need a name, GPS coordinates, and an altitude. The altitude is relative to the sea level, so you need to figure out the ground altitude and add the height of the reference point (e.g. height of the building). In the future, the ground altitude will be computed automatically.

Hint: it is better to set the altitude of the topmost part of a building. This is because it will be much easier to aim when viewing a panorama.

Upload a new panoramic photo

You can upload a new panoramic photo from the home page. Besides the actual picture, you need to specify the GPS coordinates where the picture has been made, and the altitude (exactly like reference points). If the picture encompasses 360° (i.e. the left-most edge connects to the right-most edge), then tick the appropriate box.

Once the picture is uploaded, it may take a while for the tiles to be generated. If the visualisation only show grey squares, wait a bit and try to refresh. Depending on the size of the picture and the CPU of the server, generating tiles can take from a few seconds to a minute.

Calibrate the panoramic photo

Now, you should be able to zoom and pan in your picture. But the azimuth and elevation are completely wrong, because the panorama is not yet calibrated.

To calibrate it, you need to do the following:

1. Find a known reference point on your picture
2. Right-click on its location, and in the menu, select its name

You should repeat these steps for as much reference points as possible, since it will increase the accuracy of the interpolation. The minimum number of reference points is two for normal pictures, and one for 360° pictures.

Once the panorama is calibrated, the azimuth and elevation should be meaningful! You should also see colored circle indicating the location of other panoramas.

Panorama view

This is the main view, where you can pan and scroll a panorama.

Color code

In a calibrated panorama, you should see colored circles:

• Blue circle: reference point that was referenced by a user during calibration;
• Green circle: estimated location of a reference point, determined by interpolation between known reference points (the blue circles);
• Red circle: estimated location of another panorama. You can click on the circle to switch to the view from this panorama!

Mouse interaction for panorama view

• drag image to move around
• scroll to zoom in/out
• right-click to get the Reference points menu, where you can add and remove reference points

Keyboard shortcuts for panorama view

• Pgup/Pgdown: zoom in/out
• ←/↑/↓/→: pan the image
• Home/End: turn backwards (180°)

Installing celutz

See INSTALL.md.