Questions tagged [photogrammetry]

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

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37 views

Extract terrain coordinates as seen from a viewpoint + FoV in a digital globe

Context Every one working with photogrammetry or 3D knows what a depth image is. For example OpenCV defines a "depth map" from a stereo pair, e.g.: where the darker a pixel is, the greater ...
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34 views

Difference between GIS mapping and Photogrammetric mapping

I can't seem to understand both type of mapping. I am planning to make a drone for mapping and I am confused about picking one. My purpose is to take photos of specific area and do 3D modeling of that ...
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2answers
37 views

Do I need IMU data for image stitching and orthomosaic generation?

Background: I am working on low-cost raspberry pi based camera system to integrate it on drones as an external module. So, I am using Pi camera and UBLOX Low cost GPS receiver which logs data in CSV ...
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83 views

Standard(s) to store and share geolocation and 3D orientation data for an object, e.g. a raster

As an example, GeoTIFF is a great standard to embed geolocation data into a raster file for cartographic purposes. But in that case, raster files are usually supposed to be on the projection plane. ...
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12 views

Orientation in 3D coordinate space of a pixel in georeferenced video imagery

I am trying to find (a) method(s) to extract the position in 3D coordinate space of a bounding box (detected object in 2D video imagery) having knowledge the below: I have multiple images with ...
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DEM from overlap monocular images Pleiades

I am trying to create a DEM from 4 overlap monocular satellite images of different dates from Pleiades using UP42.com. But I could find only information about stereo images processing. Is it even ...
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383 views

Importing .obj-file in QGIS 3.10.5

I wonder if it is possible to simply import .obj and .jpg (texture) files in QGIS and implement them in an existing map. I found this answer QGIS, point clouds and photogrammetry but it isn´t exactly ...
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1answer
122 views

Photo has bright and darker on an aerial photo question

For those that work in photogrammetry world, my question is how can I correct this old aerial photo that needed to be correct from a darker and bright black and white. I would have like to have both ...
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68 views

las2las X scale and offset combination error

I am trying to reproject a section of a pointcloud from UTM30N (EPSG 32630) to OSGB36 (EPSG 27700). My pointcloud has no crs assigned to it having been saved from Cloud Compare. It originated as a ....
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62 views

Automatically georeference non-intersecting UAS photos based on contained EXIF metadata

I need to know how to automatically create georeferenced rasters from multiple non-intersecting photos taken by UAS DJI Phantom 4 Pro. All EXIF metadata is present in every photo - coordinates, ...
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1answer
159 views

Point Residual in photogrammetry

I have been working on old aerial photos on Agisoft Metashape and there is a button that company added this called the "show" point residuals. When you turn it on, it shows where the line shows. I ...
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DSM results from WebODM are not correct [closed]

I am new to WebODM and I am trying to generate DSM and Orthomosaic images using default settings in WebODM. The Orthomosaic image is correct by providing GCP but the DSM file is having inaccurate ...
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1answer
61 views

How to transform camera calibration parameters to other coordinate system?

I have all camera calibration parameters (X0, Y0, focal length, R0, P0, P1, K0, K1, coarse rotation, rotation, translation) and position of the image in WGS84 (XYZ in meters) and other parameters like ...
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Where is the option to correct for rolling shutter in ESRI's Drone2Map software?

I am looking for the proper way to enable a software fix for rolling shutter in Drone2Map.
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1answer
50 views

Drone Imagery Footprints & Quaternions [closed]

I'm trying to use Drone Imagery Metadata to plot precise (or nearly precise) Imagery footprints on the the ground and I need some help with Photogrammetry / Trigonometry / Quaternions My repo is ...
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35 views

CSF Filter for creating Bare Earth Model use in Agisoft

Can anybody tell, how to use CSF filter Plugin(Cloud Compare) in Agisoft. I am having Agisoft Metashape Professional
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1answer
542 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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320 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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156 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
71 views

Generating 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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36 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
81 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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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
186 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
51 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
265 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
417 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
144 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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85 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
716 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
3k 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
117 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
363 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
209 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
81 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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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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172 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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44 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
195 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 ...
4
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1answer
725 views

gdal_merge.py with memory constraints

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 ...
5
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1answer
839 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 with ...
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7answers
20k 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
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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
61 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
221 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 ...
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1answer
469 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
572 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
457 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
219 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
48 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 ...