FYI, I am just in the process of completing an introductory tutorial on MicMac including orthorectified imaging. At the moment it is all in French, I will translate it to English as soon as this initial draft is proofread by some friends (ongoing work so the included images have not yet been shrunk to a manageable size ... huge PDF document at the moment).
In the mean time you can have a look at the pictures to see what topic will be addressed: http://jmfriedt.free.fr/lm_sfm.pdf The topic of UAV is addressed with some images acquired from a toy and processed using MicMac (p.13 of my document). MicMac is absolutely fascinating and well worth the time: I have only been involved for the last couple of months but can't stop acquiring pictures for SfM everywhere I go now. Any French speaking reader on this list who might have some comment on the document is welcome to do so. JM ----- Mail original ----- De: "Brent Fraser" <[email protected]> À: "Lene Fischer" <[email protected]>, [email protected] Envoyé: Vendredi 20 Juin 2014 15:32:41 Objet: Re: [Qgis-user] OpenSource software for Drones Lene, While I had been following DIY UAV effort for may years, I just seriously started about 18 months ago. My goal was to be able to reliably provide ortho-rectified high resolution imagery. Here are some of things I've learned: 1. It is possible to buy some off-the-shelf systems (e.g. www.aeryon.com/products/avs/aeryon-scout.html ) but they can cost $20K to $60k and are not "open" (on the other hand, they are very reliable). 3DR (the commercial store for DiyDrones) has cost-effective, open systems. They just released their Iris/Pixhawk systems. 2. The DIY Drones ecosystem is mostly populated with people who just want to build, fly, and experiment with their own UAV platforms (frame, powertrain and flight controller), but there a few people interested in acquiring and processing UAV imagery as well. Personally, I look at a UAV as [just] a camera positioning system ;) 3. Most of the software development effort in UAV image processing comes from the "computer vision" space (e.g OpenCV). Google "structure from motion" for more info on that type of processing chain. I'm unsure if that method pays enough attention to rigorous image geometry to produce accurate ortho-rectified imagery. Maybe; at any rate I want DEMs and geotiffs as an end result (I think) and that chain tends to produce non-georeferenced 3D models. And if you've got a few hours to burn reading current research, google "UAV SLAM"... 5. MicMac ( http://logiciels.ign.fr/?-Micmac,3- ) seems to use photogrammetric principles, is set up to use UAV imagery, and is Open Source, but as I mentioned before the learning curve is steep. Their user forum ( http://forum-micmac.forumprod.com/ ) has links to the user doc (280 page PDF!) and some sample data to work thru the examples in the user doc. Another possibility is OSSIM/OTB, and while their algorithms are excellent, I don't think the software is set up to deal with hundreds of images (bundle adjustment, etc), and it doesn't produce DEMs (yet). 6. Lots of R & D to be done yet. For example, using RTK/Post-processing to calculate accurate camera centers (so no ground control points necessary). Some models of the cheap UBLOX GPS receivers can generate pseudo-range info, so RTKLib is a possibility. Good Luck! Best Regards, Brent Fraser On 6/19/2014 9:29 AM, Lene Fischer wrote: Thanks for all the good links – I´ll now have something to look into Regards Lene Fischer Associate Professor Department of Geosciences and Natural Resource Management University of Copenhagen MOB +45 40115084 [email protected] SCIENCE_bomaerke_UK Fra: [email protected] [ mailto:[email protected] ] På vegne af Stefan Sylla Sendt: 19. juni 2014 04:39 Til: [email protected] Emne: Re: [Qgis-user] OpenSource software for Drones Even though its not QGIS-related, but check this out: http://wiki.paparazziuav.org/wiki/Main_Page View this message in context: Re: OpenSource software for Drones Sent from the Quantum GIS - User mailing list archive at Nabble.com. _______________________________________________ Qgis-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-user _______________________________________________ Qgis-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-user _______________________________________________ Qgis-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-user
