====== gipfel ====== gipfel is a tool to find the names of mountains or points of interest on a picture. It uses a database containing names and GPS data. With the given viewpoint (the point from which the picture was taken) and two known mountains on the picture, gipfel can compute all parameters needed to compute the positions of other mountains on the picture. Additionally, gipfel can try to guess these parameter if only one mountain is known on the picture. In this case, a few other peaks need to be marked, but it is not necassary to know their names. gipfel can also be used to play around with the parameters manually. But be warned: It is pretty difficult to find the right parameters for a given picture manually. Requirements ============ - gipfel works on UNIX-like system (e.g. Linux, *BSD and probably others). - You need fltk-1.1.x from www.fltk.org. - You need the ccmath library (http://freshmeat.net/projects/ccmath/). Installation ============ - Unpack the tar file and run ./configure; make; make install The Data File ============= As stated before, gipfel needs GPS input data. The input data must be an ASCII file with one line per mountain / point of interest. Each line must contain the following values separated by a comma: ,,,,, and may be left empty. The following line is a valid example: SMTSBG,Simetsberg,,47.56617,11.25358,1836 Fortunately, there is a great website http://www.alpin-koordinaten.de, where you can download a suitable file containg quite a lot of data mostly concerning the alps: Click on the "Suchen" button and the click on the diskette symbol below the first table then select "Fugawi 3 TXT" format and click on "Download". The resulting file has already the right syntax for gipfel, but contains some duplicate entries. Use: sort -u -t , -k 2,2 > to remove these duplicate entries. Obviously you can easily add your own entries to the data file or add them to the database at http://www.alpin-koordinaten.de. Running ======= To start gipfel, enter gipfel -v -d Where is the name of the location from which the picture has been taken. This name must be found exactly in the datafile. is the file conatining the GPS data. is the actual picture in JPEG format. You should now see a control window and the actual picture. You can use the controls in the control window to modify the view parameters. These are: - View direction - Nick angle - Tilt angle - Scale - Visibility Play around with these parameters, until you see the names of one or two mountains, which you already recognize on the picture. Now click on the small cross at the left of the name to mark it and drag them to the position of the mountain on the picture. The marked mountains should have a red flag. If you have positioned two mountains, you can now click on the "comp" button in the control window. If you have only marked one mountain, you need to mark other peaks on the picture using the green flags which you find at the center of the picture. Make sure, that the one marked mountain has a red flag containing a "1" if it has a "2" in its flag, just keep clicking on it until it changes to a "1". Then click on the "guess" button. If the result is disapointing, try to adjust the visibility parameter as only visible mountains are taken into account during the "guess"-process. Troubleshooting =============== - Obviously gipfel can only be as good as its input data. If there is no data about the mountains on your picture, you are out of luck... But as the data file format is pretty simple and GPS receivers are common, you can build up your own datafile. - gipfel only works with full normal unmodified pictures taken with a non-distorting standard objektive. Stitched panorama pictures will not work! - I have no idea, whether gipfel works correctly on pictures taken on the southern hemisphere, but I would appreciate any feedback about it. Commercial Applications ======================= If you are interested in a commercial application of the methods used in gipfel, feel free to contact me. Acknowledgements ================ Thanks to the guys from http://www.alpin-koordinaten.de for their public GPS database. Thanks to Carsten Clasohm for his great gallery at http://www.clasohm.com/. His pictures are good test cases for gipfel! Also have look at their other site http://www.alpen-panoramen.de/ ! I also want to thank my brother Martin Hofmann for his tips and the discussions. DISCLAIMER ========== gipfel must NOT be used for real navigation. You should not rely on the results of gipfel. Johannes Hofmann (Johannes.Hofmann@gmx.de) May 10, 2005