Skip to main content
16 votes
Accepted

Drone aerial imagery to QGIS

Yes you need to Georeference the images. The Exif data explains where the photo was taken, so it describes where your drone/camera was at that time and often many other values (heigth, bearing etc). ...
Andrew Jeffrey's user avatar
11 votes
Accepted

Merging drone/photogrammetry-derived DEM and satellite-derived DEM using ArcGIS Pro

Assuming: both are in the same projection / coordinate reference system, you have a Image/Spatial Analyst license, and NoData has been set correctly on the High res DEM. You could use a Raster ...
user2856's user avatar
  • 66.6k
9 votes

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

I've done this before with success using the Photosynth Toolkit (http://www.visual-experiments.com/demos/photosynthtoolkit/), except instead of a drone I was hanging my head out of a small plane ...
crld's user avatar
  • 892
7 votes

Drone aerial imagery to QGIS

Give RAPID for DJI a try. It will geo-reference and process up to 100 images from any DJI sensor or drone for free. The results are WGS84 Lat/Lon GeoTIFF format digital elevation models, point clouds ...
dronemapper's user avatar
6 votes

Determining bare earth DEM from unclassified LAS file?

This can be done with a pdal filter using either Simple Morphological Filter (SMRF) or Progressive Morphological Filter (PMF) algorithms. Quick pdal ground --cell_size=5 --extract input.laz out-...
matt wilkie's user avatar
  • 28.2k
6 votes
Accepted

Obtaining the average red, green, blue values within grid cells in QGIS?

You can use Zonal Statistics tool.
Kadir Şahbaz's user avatar
5 votes
Accepted

Postprocessing with NMEA-data if no rinex-data is available

It is not possible to do post-processing using NMEA output only, because it only contain final computed positions. And to do post-processing you need the pseudaranges, phases, etc. for each satellite ...
Camilo Rada's user avatar
  • 1,219
5 votes
Accepted

Georeference single drone image from EXIF data

As requested, posting my own (partial) answer. The actual math is not too bad, but there are surrounding issues making application difficult: UAV camera focal length specs seem to be before sensor ...
Houska's user avatar
  • 8,016
4 votes

Seeking software for making digital elevation models from UAV aerial imagery

For commercial solution take a look at http://www.3dsurvey.si/ And for opensource I would certainly try https://github.com/OpenDroneMap/OpenDroneMap
Uroš Preložnik's user avatar
4 votes

EVI calculation from UAV multispectral survey

The common definitions for these coefficients when using MODIS are: L=1, C1 = 6, C2 = 7.5. The C1 and C2 coefficients are aerosol resistance terms that rely on the blue band to partial out atmospheric ...
Jeffrey Evans's user avatar
4 votes
Accepted

Finding long, lat coordinates of points on building pictured by drone

You can't unless you know the distance from the ground, and the pitch, roll, and yawl of the camera (in addition to the CCD size and camera lens info you have). Plus, the onboard drone GNSS may not ...
GBG's user avatar
  • 9,930
4 votes
Accepted

Why do RGB values seem very high for my multispectral orthomosaic imagery?

Your imagery is 16bit. 16bit data can contain a lot more information than 8bit. The signed range of integer values that can be stored in 16 bits is −32,768 to 32,767 and the unsigned range is 0 to ...
user2856's user avatar
  • 66.6k
4 votes
Accepted

Wrong parameters when georeferencing single drone images

My experience is with a Mavic Mini, which does not have published lens distortion specs and has only consumer-grade GPS, not RTK correction. With that caveat in mind, I've found you just need to ...
Houska's user avatar
  • 8,016
3 votes
Accepted

Drone that generates a point cloud from photography

Probably they have made a structure from motion function. With the mosaic of several pictures around an object you can create its 3d model and get also the point cloud. Thats nothing too spectacular. ...
Matte's user avatar
  • 6,245
3 votes

Satellite signature of reindeer carcasses

I had a look at Sentinel imagery. The S2 images are too cloudy, as you can check here. And with S1 there is an image on 27/8 (the day after the lightning) and another one with similar characteristics ...
Simon Gascoin's user avatar
3 votes

Why is the altitude information of the geotag from a drone/uav/uas/rpas (Phantom 3) so innaccurate?

10-15 m is indeed the uncertainty that you get with a normal GPS in Z (it is roughly 3 times less accurate than XY). Furthermore, the XY errors are compensated by the large number of photograph on ...
radouxju's user avatar
  • 49.7k
3 votes

Seeking software for making digital elevation models from UAV aerial imagery

A high level method for creating Digital Elevation Models, Point Clouds and Orthomosaic maps using UAV aerial imagery and open source software (linux workflow). Obtain a set of NADIR or NADIR + ...
dronemapper's user avatar
3 votes

Seeking software for making digital elevation models from UAV aerial imagery

Delft University is doing a lot of research into CityGML, one of the upcoming standard formats for visualising 3D building information. They have a viewer and also this tool, to turn LIDAR info into ...
Peter's user avatar
  • 51
3 votes
Accepted

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

I found this page in the Pix4D documentation which states: Keypoints are points of interest (high contrast, interesting texture) on the images that can be easily recognized. The number of keypoints ...
Fezter's user avatar
  • 21.9k
3 votes
Accepted

Smooth mosaicking of smaller orthomosaics to form a homogenous mosaic

That is noise / offset pixels or unexpected dark or light strips fringing an object. Data from airborne multispectral or hyperspectral imaging scanners shows a pronounced striping pattern due to ...
Maxima's user avatar
  • 1,701
3 votes

Seeking algorithms for DEM generation?

Based on this post How can i create a Digital Elevation Model from satellite Images? If you have stereo pair of satellite images or overlapping aerial photographs or even UAV acquired imagery, you ...
whyzar's user avatar
  • 12.1k
3 votes
Accepted

Software Recommendations: make a flyover video from GPX log?

I can't tell how that video was created, but you should be able to do something pretty similar with a combination of several techniques in Google Earth Pro. I'll list the general steps here, and you ...
Christiaan Adams's user avatar
3 votes
Accepted

Getting coordinates of pixel from georeferenced drone photo?

The approach you're looking for is called monoplotting in photogrammetry. If given your assumptions on camera orientation, you will need a digital elevation model (unless you also assume the ground is ...
danscr's user avatar
  • 121
3 votes
Accepted

Abnormal Output of OpenDroneMap with GCP file

The problem in its processing is that it is georeferencing all ground control points with the same elevation, when they clearly do not have the same elevation. The georeferencing process is not ...
Gabriel De Luca's user avatar
3 votes
Accepted

Higher spectral and spatial detail for high-resolution images using ArcGIS Pro Image Segmentation

The spectral and spatial detail values range from 0 to 20. Since they are using the default values of 15, you wouldn't be able to increase your spatial and spectral detail by much more. However, the ...
Riley Anderson's user avatar
3 votes

Selecting grid cells by color of image

To solve your problem, you can use an expression to create a new field in the grid layer and then select them for a range of colour. Open the Field Calculator, select Create a new field (I suggest ...
Val P's user avatar
  • 3,868
3 votes
Accepted

Classification of drone imagery (RGB) with SCP

It is possible to split the orthophoto into 4 rasters with each a band and use them to create the ROI polygons. Open SCP --> Click on 'Split Raster Bands' --> Select your orthophoto in Multiband ...
OmteK.'s user avatar
  • 81
3 votes

Georeferencing single drone image from metadata (gimbal angles, flight angles)

An application like EXIFTool will allow you to see the pitch, roll, and yawl for both the camera and the aircraft. There are also Python solutions for reading the EXIF data from the aircraft camera ...
GBG's user avatar
  • 9,930
3 votes

Mapping image from drone in QGIS

No, QGIS cannot exploit the image location, elevation,pitch, roll, and yaw to automatically georeference your images. You can manually georeference individual drone image yourself using QGIS. See ...
GBG's user avatar
  • 9,930
3 votes

Can PPK (NOT RTK) be done with any mapping drone?

Post-processing depends on raw GNSS data being captured (pseudo-ranges for Code post-processing, Phase information for Carrier post-processing.) If the drone has only captured coordinates, you don't ...
Trams's user avatar
  • 749

Only top scored, non community-wiki answers of a minimum length are eligible