Questions tagged [photogrammetry]

The practice of determining the geometric properties of objects from photographic images.

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1answer
57 views

CHM (Canopy height model) = DSM (Digital surface model) - DTM (Digital terrain model)

I want to create a canopy height model (CHM) which has the height of objects (trees, building, etc.) from DSM and DTM. Below is the step by step procedures which I did so far. I use open source s2p ...
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0answers
16 views

Calculate canopy openness using RGB mosaic from UAV orthorectified aerial images

Canopy openness of trees was obtained easily from digital photographs processed with Gap Light Analyzer. Image processing involves the transformation of image by the division of pixel intensities into ...
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0answers
88 views

Conversion of Fbx or Obj to Cesium Tiling [closed]

I have a an OBJ File and a FBX File of very large size (OBJ = 25GB & FBX = 6GB) I'm looking for a way to convert either of them into Cesium Tile Format. I have tried using Pix4D software which is ...
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0answers
89 views

Extract water areas from aerial photogrammetry DEM in QGIS

We are working with peatland restoration sites providing aerial photogrammetry of the restoration progress. We want to differentiate between areas water and bare peat which can look very similar in ...
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1answer
40 views

How to generate DEM Generation in LPS

I have a Cartosat 2.5 m Imagery and Block files along with DSM Data. I wanted to generate DEM using Leica Photogrammetry Suite Software. Does anyone know the steps of generating same? I have to edit ...
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26 views

Object height determination through Split Stereo image visualization QGIS

Is there any way to display (Aero-triangulated) left and right images (Stereo photogrammetry) in 2 mapview/viewport(different viewport/Map View/Multiple Canvas) in QGIS. So that we can use Sensor ...
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1answer
50 views

Focal length vs Principal point

I have set of areal imagery. One of a parameters I get with images is camera's Principal Distance , what I'm looking for is Focal length, but I don't have Focal length at the moment I tried to ...
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27 views

Coordinate system of OpenDroneMap georeferenced PLY

I'm trying to work out the coordinate system of the georeferenced PLY from opendronemap. I have found a proj.txt file that contains the proj4 projection: +units=m +no_defs=True +datum=WGS84 +proj=utm ...
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0answers
55 views

Automatically Recognised Targets for Combined Laser Scanning and Photogrammetry

I'm currently performing an engineering honours thesis on terrestrial photogrammetry and laser scanning in Archaeology. Both methods will be used to document a single location first and analysis will ...
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1answer
121 views

PDAL error: “Couldn't create filter stage of type 'filters.cpd'”

I would like to use the cpd filter to transform a point cloud, but I am heading to the following error: RuntimeError: Couldn't create filter stage of type 'filters.cpd' which comes from the ...
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1answer
44 views

Interpolation of holes resulting from DTM groundfiltering of SfM pointcloud

I am wondering if there is an efficient interpolation method to close the holes in a dtm resulting from groundfiltering. At the moment I am directly interpolating the point cloud to a raster using ...
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1answer
185 views

Building height calculation from stereo Satellite images (Satellite Azimuth and Satellite Elevation)

Can anybody help me in how to calculate building height from stereo satellite images sensor metadata (Mean satellite Azimuth and Mean Satellite Elevation) Stereo Satellite Images Azimuth's (335....
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1answer
285 views

DSM quality lower in ArcGIS Pro than PhotoScan

I am processing aerial photos collected with an automated drone flight into orthomosaics and DSMs, and have noticed the quality of outputs produced in PhotoScan is much higher than those produced in ...
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1answer
79 views

Error importing ground control points ArcGIS Pro

I am working on processing aerial images from an automated drone flight in ArcGIS Pro. The photos import into the Ortho Mapping workspace just fine, and the Quick Adjust alignment runs without ...
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0answers
65 views

GDAL : transfer metainformation

I'm using Agisoft Photoscan 1.4.2 to build DEM from UAV photos and in last versions thay produce DEM multipage tiff format and I want to convert it to tiff with metainformation preserved. According ...
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1answer
567 views

Photogrammetry route flown using Litchi misses photos at some waypoints

I have recently started using Litchi to fly waypoint-based photogrammetry flights with a DJI Phantom 4 Pro. The routes were created in DJI Flight Planner, then edited, uploaded, and executed in the ...
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2answers
2k views

What is the difference between Key-Point, Tie-Point in Photogrammetry?

I'm looking into the reports & the Mechanism of UAV Photogrammetry software like Pix4D and AgiSoft. These two words are mentioned in a lot of support documentation, but they are defined no-where. ...
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1answer
86 views

Aerial Triangulation by using GPS height

Is it possible to use GPS geographic coordinates & ellipsoidal height not orthometric heights in Aerial Triangulation?
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1answer
340 views

Which type of point cloud is more accurate: from airborne LiDAR or aerial photos?

I have been offered two types of point cloud for my 3D Project. The data will be used by the environmental agency in various projects e.g. flood-risk analysis, dyke conservation, and nature ...
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2answers
102 views

Getting a flat surface from DSM for height calculation?

I have a DSM done trough photogrammetry with the software Agisoft Photoscan of a forestry experiment and I need to accomplish an analysis of the mean height from it. My problem is that the profile has ...
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3answers
69 views

How many forest clear cuts and how big are they?

I have forest stand characteristic data from northern Sweden. We have interpreted multiple years of aerial photos and now have polygons outlining different forest stand ages over time (e.g. clear cuts,...
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0answers
60 views

Pixel values in a mosaic with TIFF images in Photoscan? [closed]

I´m trying to understand how works the creation of a mosaic in photoscan or in other photogrammetry software. When I use various TIFF images with information in their pixels (in my case temperatures) ...
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0answers
111 views

Counting treetops from the DSM [duplicate]

I want to measure tree heights in the forest using drone photogrammetry. So far it's easy to measure single trees height using fugroviewer in the pointcloud, but I would really like to measure whole ...
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0answers
42 views

Cropping Oblique Photos to Geographic Feature

Let me preface this by stating that I know I'm in the GIS neighborhood and I'm asking a code heavy question, but my hiccup here isn't the programming - it's the GIS and associated math. I am writing ...
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1answer
181 views

Dependence of point cloud data on camera parameters? [closed]

I want to do a 3d-reconstruction of a road surface using 'Structure from motion'. After taking the required image set of the road surface, I want to obtain the point cloud data using some open source ...
3
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1answer
447 views

gdal_merge.py with memory constrains

I export bunch of DEM files (10000x5000) from Photoscan and I need to combine them with gdal_merge.py but the problem is that it consumes all the memory availible and can't finish processing. What ...
4
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1answer
676 views

OpenDroneMap: How to produce correct georeference ortophoto from UAV?

I am trying to produce proper georeferenced ortophotomap from UAV mission using OpenDroneMap (ODM), like I have done the same thing using APS Suite from Menci In both cases I have the same images ...
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7answers
17k views

Drone aerial imagery to QGIS

I used Phantom DJI Standard 3 drone for some aerial photos of an archaeological site. When I viewed the properties of the jpeg file, it contained Longitude (like this: 22; 14; 37.701258239) and ...
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5answers
2k views

Creating photogrametric point cloud of an object from distributed photographs, here: Making accurate 3D model of building using UAV imagery?

Is there a way of creating a photogrametric point cloud from a set of densly distributed photographs of an object? Application: I am trying to investigate if creating a 3D model (point cloud) of the ...
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1answer
59 views

Can targets placed on the facades of a building be used to increase the accuracy of a point cloud of a building generated from Drone/UAV/UAS imagery?

Can targets (used for registering point clouds) mounted on a building be used to increase the accuracy of a point cloud generated from UAV imagery?
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1answer
199 views

Creating vector datasets from 3D models

I'm an archaeologist and have been using photogrammetry to record rock art sites in northern Australia. That is working very well (we're using Agisoft Photoscan, it's fantastic). My question relates ...
2
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1answer
361 views

Georeferencing an oblique angle photograph in repeat-photograph studies

Backround: Aerial photography and remote sensing can be used to measure current land cover and recent land use change. However, these technologies are fairly recent and therefore time series are ...
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2answers
527 views

Looking for real-world DJI Phantom 3 Professional sample geo-tagged images for testing

I am looking for sample DJI Phantom 3 Professional imagery for testing purposes with the Drone2Map for ArcGIS Beta software. So far I am finding the application very polished and easy to use but I am ...
2
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1answer
442 views

Setting elevation data for tie points in Pix4D

I am currently working in Pix4D and am trying to assign elevation data to my selected tie points. I have aerial images taken using a camera with GPS from an aircraft and am working with a fairly ...
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0answers
199 views

How Does Erdas calculates the ground coordinates for each pixel in the image

How Does Erdas calculates the ground coordinates for each pixel in the image I have a conceptual question regarding photogrammetry, what is the formula used by Erdas to find the (X,Y,Z) on ground. ...
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0answers
47 views

Erdas LPS : how to rename points_ID values?

I'm working with ERDAS LPS 2014, i would like edit the name given for my GCPs and TPs (add the following suffix : "_w"). I tried to do that using the "formula" menu... in vain. I did not find a ...
2
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1answer
692 views

Existence of fiducials marks in a digital camera file

Existence of fiducials marks in a digital camera file I have created a generic digital camera file using Erdas 2015 with the following data in it: LPS Camera File Version: 2.0 Camera Name: "generic ...
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0answers
187 views

ArcGIS Pro crashes when importing photogrammetric multipatch? [closed]

I am new to the ArcGIS platform, so please bear with me. I have run some tests on both ArcScene and ArcGIS Pro before my jobs decides with program to buy. ArcScene imports 3d models exported from ...
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1answer
89 views

Deriving equations of Epipolar lines for linear array scanners? [closed]

I'm going to obtain the equations of the Epipolar lines of a given image captured with linear array scanners. There are some papers addressed this subject, but they haven't stated key points in detail,...
2
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1answer
91 views

Rigorous geometrical models for InSAR imagery?

I'm looking for rigorous geometrical models for InSAR imagery. I'm familiar with the rigorous models for SAR images, but I don't know the model for InSAR. I searched through the internet, but I didn't ...
2
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1answer
243 views

UAVs and using ground control

I have been having a conversation at the office about whether to use ground control when using drones/UAVs to capture aerial images. The ground control that I am referring too is any permanent survey ...
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2answers
7k views

Using Phantom 3 Pro to capture aerial imagery for small site plans and derive DEM? [closed]

I am curious if this consumer UAV can be used to capture imagery for further processing to stitch seamless imagery and to use as input into stereo/photogrametry software to create reasonably accurate ...
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1answer
583 views

Open source software for 3 D vector editing on top of stereo images

I am looking for an open source software that could be used to digitize 3D vector objects from a stereo pair of remotely sensed images. Photogrammetry softwares are too expensive for my use (giving an ...
2
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1answer
769 views

Automatically adding Z-values from a DEM to an already created polygon

We have excavated a very large 5.000 year old fish fence, which was documented by photogrammetry, and is now being digitized. I started digitizing the orthophoto in QGIS and everything is cool. Now I'...
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1answer
110 views

latitude longitude into corresponding location in a image [closed]

I have an image , some data on this image, some data on the camera that took that image and a piece of code. And i'm trying to find the location (Px,Py) in the image from (lat,lon). my problem is ...
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1answer
2k views

Real-world dimensions of a 3D object in VisualSFM or MeshLab

I have a good-quality, precise 3D scene reconstructed from photographs/video by VisualSFM. All camera parameters, including 3D position and lens details, are known. Now, that the hardest work has ...
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2answers
819 views

Aerial photogrammetry book with all the math

Can anyone recommend a book that hits all the math for the general situation of doing serious photogrammetry calculations on aerial photographs? Particularly an inexpensive book or one I can get ...
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0answers
514 views

Orthorectification errors in ArcMap when including RPC data

I am trying to orthorectify satellite imagery with a DEM in ArcMap. I have already georeferenced the raster. The imagery came with an RPC TXT file, but when I change the name of the RPC file to match ...
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1answer
1k views

Software for image orientation (aerial triangulation)

I'm trying find a software which can orient an UAV Imagery using GCPs (Ground control points in UTM Coordinates system) and Camera calibration (only camera focal length, p1,p2, k0, k1, k2, k3 and ...
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2answers
237 views

Stereoscopy Software

I'm learning the Manual Photogrammetry process, Stereoscopy, to Process UAV Imagery. I'd like to know about others software, especially open source or low cost. ERDAS Imagine, Erdas Extensions for ...