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7

Full Credit to Henri EisenbeiƟ (Author) from the dissertation 1.1.1 UAV photogrammetry Extract: "The new terminology UAV photogrammetry describes aphotogrammetric measurement platform, which operates remotely controlled, semi-autonomously, or autonomously, without a pilot sitting in the vehicle. The platform is equipped with a photogrammetric ...


5

For ground control, you're going to want something easily visible from your UAV. Temporary GCPs may be good enough for your purposes. Personally, I've used weighted plywood painted with an arrow in bright colors like yellow and red. The tip of the arrow gives you a precise location to both set your RTK unit over and visually identify when georeferencing ...


5

So if I assume the following variables: x = camera sensor x size y = camera sensor y size f = focal length h = height above ground And I am looking for: ay = photo y ground distance ax = photo x ground distance Would these formulas work? making sure that I compare the proper units to the proper units. (f/h)*x = ax (f/h)*y = ay Does this make ...


4

In Austria and Germany Karl Kraus taught remote sensing and photogrammetry and wrote several books which are IMO fundamental and very good for the understanding of this matter, despite the age of these books. Unfortunally he died in 2006. There is a translation made by Ian Harley and Stephen Kyle. Karl Kraus, Photogrammetry, Volume 1, 2007: Geometry from ...


4

fiducial mark are used to define the coordinate system of the photograph. With film photograph, the paper moves under the objective and can get further distorted during storage and development, so you need to localise the image on each frame. On the other hand, digital sensors are fixed, so you don't need any mark on the image to define the coordinate ...


4

I can confidently say yes. Add in some surveyed ground control points and you can easily get 10 cm positional accuracy. So far there are two big players that I have been using pix4d is by far the best but it is the most expensive it is really good for editing mosaics. Actually pix4d now has apps to directly work with your phantom and even has a free ...


3

To calculate a volume, you need the 3D Analyst extension. 3D Analyst has several ways to calculate volumes. All methods require the data to be in a projected coordinate system. You can use TIN or Terrain surfaces. Method 1: Surface Volume This method assumes one of the surfaces is a flat plane and the other surface varies. It can calculate volumes ...


3

Opticks Image Segmentation Opticks is an open source Imagery Analysis Software. It will perform segmentation on an image and save the results to a Shapefile. The link has a short segmentation tutorial. The software runs on Windows 32/64, Linux and Solaris.


3

There is something better! Check this out: http://www.123dapp.com/. You can use 123Catch to combine many photo's into a 3D model. Then use 123Sculpt to make the model better! Alternately, try this stuff for a home-made solution: http://www.visual-experiments.com/ the guy who put it together has gone to work with Microsoft, so he's doing good things!


3

Open Aerial Map's wiki (http://openaerialmap.org/Processing) suggests GRASS GIS' i.ortho.photo and related modules (per Micha's suggestion). OSSIM http://trac.osgeo.org/ossim/ - probably best bet. http://www.digilab.uni-hannover.de/index.html - looks like it would require some development work to be useful http://www.orfeo-toolbox.org/otb/ - very active ...


2

For looking at points in QGIS you could check out lastools and their las2shp tool. That would turn your 3d point cloud (in las format) into a vector point file. lastools even has a QGIS toolbox now for full integration. Edit: Check out http://opendronemap.github.io/odm/ as an open source alternative to agisoft. https://www.youtube.com/watch?v=e2qp3o8caPs


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We have found the image segmentation model in Spring to be comparable to eCognition. Spring is a free remote sensing software developed by the Brazilian government.


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There are successful solutions available based on eCognition, for instance: http://www.trimble.com/imaging/pdf/TM18_FINAL_INPHO.pdf eCognition offers the possibility to translate your mind model (why you see buildings in our images) into computer understandable code (= rule set). The eCognition Developer is the environment to create rule set. A good rule ...


2

There are several softwares for doing this. Here is a non exhaustive list : Commercial licence : Imagine Photogrammetry (= formerly LPS) This is very powerful but very expensive ENVI DEM module photoscan Not very expensive, but more oriented toward drone image processing, so not the best for satellite data Open source : Orfeo Toolbox Not tested for ...


2

We have created an webpage with a script that will perform the calculation for you: Aerial Camera Ground Footprint Calculator. You just have to enter the variables mentioned and click the Calculate button. Please note the calculator interface is in English, but the primary site language and explanations are in Spanish.


2

I guess that your fish fence polygon covers several DEM grid cells. Normally you would extract DEM grid values to a point layer with a plugin tool like Point sampling tool. If you polygons are very small in relation to the DEM cells you could use the centroid of the polygon as a new point layer doing the Point sampling plugin tool on that point layer. With ...


2

I think the paper Application of RPC model for InSAR phase evaluation is good to start with and then you can continue with the references of that paper The paper Robust Estimating Three-Dimensional Ground Motions from Fusion of InSAR and GPS Measurements is another good resource This book can be a good resource, too. It's not completely relevant but ...


2

My photogrammetry lessons are way back so this is just a suggestion. First of all, read some documents, like this or that. I think you need more params, e.g. the FOV of your camera. Also what you need to keep in mind, is that you want to preserve an "endlap of at least 50%" for total stereoscopic coverage in resulting stereo pairs, according to this ...


1

You may click on some automatic tie point (the one you want to assign the elevation to), and then click: After clicking the correct position on more than 2 images, the coordinates will be displayed in the up-right. Change the point type from "manual tie points" to "3D GCP" and then change the elevation value. Repeat this for 3 points, well-distributed on ...


1

Yes you can. I been flying a Phantom 2 for the last year. The phantom 2 does not have the camera like the new Phantom 3 does so I been using the H4-3D gimbal with a Go pro Hero 3.Unfortunately Go pro cameras do not have the capability to attach coordinates to images so I use control points to georefence the models. I process the data with Agisoft photoscan ...


1

For the past two months since I asked this question, I haven't been able to reproduce the problem. I have come to the conclusion that the star markers indicated photocenters that contain generated tie points, and even when those tie points are deleted the attribution remains.


1

small format aerial photography is another option. http://www.amazon.ca/Small-Format-Aerial-Photography-Principles-applications/dp/0444532609 it is a great book with several different approaches to collecting small format high resolution imagery (kites, balloons, uav etc). they also have chapters on workflows, types of error, and case studies. lots of ...


1

So i found the answer and i decided to shere it. Apparently R0 , A1 , A2 has only one value and they are the radialdist_A1 , radialdist_A2 and distortion_R0 in the code. I also discovered that i needed only to convert the (lat,lon) to utm zone 32. And then everthing works!


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First part is getting the point cloud on the correct scale, this can be done with GCP that are set to known real-world co-ordinates, or tied to GPS. Measurement functionality isn't present within VisualSFM, so Meshlab will need to do the job for you. Once you have imported the PLY file that visualsfm has generated into Meshlab, click edit, Measuring tool. ...


1

http://books.google.co.in/books/about/Introduction_to_Modern_Photogrammetry.html?id=JdNTAAAAMAAJ&redir_esc=y is an other good option. Clear and simple explanation.


1

Yes, I think SFM Toolkit (FOSS)is used for this task. Although I have not used it, it is very well reviewed. I have used Stereo GIS by SimWright and had good success. They may give you a free trial.


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if your UAV images are well overlapping (at least 3 images for each observed feature), I recommend Agisoft Photoscan. It is not free but not very expensive. You can also have a look at orfeo toolbox, but it is not as easy to use as Erdas. However, they do have some tools for residual registration http://orfeo-toolbox.org/


1

Here is Easiest and free way to georeference an image file using QGIS and here are more links Georeferencing an image in QGis is a very simple task. Here is how: Run QGis and create a new, blank project. You don't need to save it. You should already have some other georeferenced material, the best is aerial photos, but also shapes could do. Open ...


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Multipatch feature are supported 3D building. So you can try to do this method. plz refer to this link. http://resources.arcgis.com/en/help/main/10.1/index.html#//00q80000007n000000


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Some time has passed, the topic is still relevant since new software became available: Did anyone try out the NASA Ames Stereo Pipeline (ASP, http://ti.arc.nasa.gov/tech/asr/intelligent-robotics/ngt/stereo/)? The source code is on github. Furthermore, in the open source software Orfeo Toolbox (OTB, http://orfeo-toolbox.org) they offer "One-click DEM ...



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