Questions tagged [photogrammetry]
The practice of determining the geometric properties of objects from photographic images.
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Dashcam imagery and object location x and y to lat/long [closed]
If I have a dashcam mounted on a vehicle looking ahead, how can I find a location of a point on the ground? The dashcam is recording at 60fps. Basically, the idea is first to use deep learning models ...
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Photogrammetry and stereo with QGIS [closed]
QGIS for stereo and photogrammetry
I am looking for a stereographic photogrammetry solution package for QGIS software.
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Couldn't find coordinate system NRW Netz zone 2 in Metashape
I have photogrammetry data from Germany, I got information of the coordinate system used in this project for Ground Control Point (GCP) is NRW Netz77 zone 2. I couldn't find anything on epsg.io or ...
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Metashape outliers underneath the ground surface
I flew a DJI Mavic 2 Pro with 80% overlap horizontal and vertical at 30m high with little wind at an angle of 80 degrees. It seems that the points are also mirrored underneath the ground surface. What ...
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Orthophoto showing image banding along flight lines after reconstruction
I'm currently flying a mapping mission with a DJI P1 with the following flight parameters:
Altitude: 250m
Side/Forward Overlap: 60/80
Terrain Follow: Enabled
RTK: Enabled
Regardless of the time of day ...
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Problem with wrong DEM output after georeferencing
My goal is to georeference a DEM tiff file that I have with a reference orthophoto.
Steps to reproduce
Open orthophoto (EPSG2056) in QGIS
Open the DEM (EPSG2056) in the Georeferencer
Add GCP (I am ...
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How do LiDAR and photogrammetry DTMs differ?
Recently, I received two temporally distinct DTMs of a particular area processed with photogrammetry. The datasets were acquired about one year apart and no landscaping activity occurred at the site ...
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Classify faces of steep vertical slopes using point cloud as input
I’m trying to develop a tool for slope risk analysis with 3D models like showed in the image below. In this 3D model, the slope faces oriented in the same direction and with the same inclination have ...
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Determine Lat/Long of "off-center" point of a top-down image
I am a computer science student with a top down photo taken by a drone. This drone has relatively low to zero gimble yaw/pitch (0-10deg), isn't very high up (~15m) in flat lands pretty close to sea ...
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Does LiDAR tend to georeference better than photogrammetry?
I noticed whenever I get a photogrammetry dataset, the products (like DTM, DSM) are always misaligned from satellite imagery of the same area by a few metres. Today I received a LiDAR dataset and they ...
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Including height information when exporting images from SlantView 2
I have a set of images that were collected with a slantrange multispectral sensor (S3P). To include the radiometric calibration information from the sensor, I use SlantView 2 (Ver. 2.17.4).
I will ...
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Options for making a DEM of single-return point cloud?
I have a project site surveyed with single return photogrammetry so, all points are unclassified. It was not a problem to create a DSM of this data, but I also need a DTM.
What are my options? Will I ...
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Can PPK (NOT RTK) be done with any mapping drone?
If PPK is by definition post processed and does not require a live connection to the base-station, why wouldn’t be possible to use any drone and post process the resulting coordinate data (assuming ...
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Accuracy of key points for moving subjects
I am currently working on a project where I have a fast-moving subject (a tree) which I capture from multiple angles using multiple cameras. My intention is to use photogrammetry to create a 3D model ...
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DEM generation using Agisoft Metashape Professional
Currently, I am processing Aerial photographs acquired in 1967 and 1984 (all are acquired by frame camera) using Agisoft Metashape Professional software. What I faced is; the DEM generated from 1967 ...
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Measure an angle on an orthophoto or on a dense cloud
I'm currently working on QGIS 3..10.1, and I would to analyse my roof with UAV analysis. I have already made a dense cloud, an orthophoto and a DEM on agisoft metashape but now I would make few ...
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Georeferencing single drone image from metadata (gimbal angles, flight angles)
My question is in regards to the answer given to Georeference single drone image from EXIF data.
The answer describes how to georeference a single drone (DJI) image using EXIF data but, in the ...
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How can I have the ground sampling distance from the images?
I have some aerial images and I need to know how if I can have the ground sampling distance value from the image without calculate it from the plane fly's parameters.
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Georeference single drone image from EXIF data
Looking for an algorithm (python, formulas, whatever...) to georeference a single drone image based on its EXIF data.
Specifically, I need to translate drone GPS latitude and longitude (after ...
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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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