Questions tagged [orthophoto]
An aerial photograph geometrically corrected and adjusted for topographic relief, lens distortion, and camera tilt - such that the scale is uniform.
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Rotating orthophoto based on polygon boundary (rotated pixel)?
When I clip an orthophoto using a vector polygon, the resulting pixels orientation is north-up like as shown in the graphic below. I used Global Mapper, ERDAS, Arcmap "Clip" "Extract by Mask", "...
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Measure building lean in ArcMap?
I was wondering if anyone is aware of any tools that are available to measure building lean in ortho images from within ArcMap. I am aware of calculations and processes that can be used to measure and ...
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Using Mosaic + Orthophotos to create Mosaic produce overlap error?
I am using Mosaic + Orthophotos from the package from Datem Software. I have 7 photos that I need to generate Mosaic from Orthophotos . I am not very familiar with this software and just learn how to ...
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Orthorectification with R
How can I orthorectify an oblique image of a flat landscape when I know the conditions of the photo (coords, height, direction, lens, etc)?
I would like to perform this kind of stuff from GRASS ...
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Orthophoto land use classification in QGIS
I am using a CIR orthophoto and tried to make a land use classification with the use of Semi-Automatic Classification Plugin in QGIS. I work in QGIS 3.2 but I get errors that my ROI are too small (...
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Scale bars moving after update cause measurement issues
I'm trying to create orthomosaics with accurate measurements of rocks in a stream bed. All the photos were taken from a fixed height and scale bars were added by knowing the dimensions of GCP's along ...
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Trying to deal with pure whites, and transparency of orthomosaic in MapInfo
I'm hoping to deal with this using the raster calculator in QGIS. But, here's my issue (and I'm a pretty novice GIS user); when you bring a raster image into MI, it turns all the null ("no data") ...
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Orthophoto processed with Photoscan distorted in QGis
I processed an orthophotomosaic via Photoscan using geotagged images in EPSG 4326 and it is displayed correctly in Photoscan and GoogleEarth. When I put it in QGis it is distorted. The coordinate ...
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DroneDeploy generated Ortho shows skewed in QGIS (projections OK?)
I've recently bought a drone and have been having a lot of fun enhancing maps with very detailed orthomosaics.
The images place correctly once loaded in QGis, absolute positioning is good enough for ...
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Using Orthophotos - not multispectral - to generate Object-oriented image classification vectors?
I'm using QGIS version 2.14.3-Essen on a Macbook pro. I'm sort of new to this and feeling my way through this.
I have high-resolution Orthophotos officially sourced from local country in Sub-saharan ...
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extract roads, railways and canals out of old orthophoto
how is it possible to extract the roads, canals and or railways out of this image (black-white)?
Or how is possible to create lines at the edges of the roads, canals and or railways?
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Geometric quality of orthophotos
I have a lot of historical orthophotos, like the year 1950 of a region
I have also of the same region the orthophotos of more recent years such as 2012
The question is how to compare and quantifying ...
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Georeferencing declassified CORONA images of coastlines?
I'm trying to georeference declassified CORONA images of coastlines in order to asses coastline changes and human impact.
In most case, georeferencing is easy, but since images of coastlines can only ...
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3D visualization of terrain data and orthophoto using GRASS NVIZ via QGIS
How can I make 3D visualization of terrain data and orthophoto using GRASS NVIZ via QGIS? I am quite new with GRASS. I have only managed to get a 3D view of the terrain so far.
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Coordinate Operations Error for NAD83(2011) Alaska Zone 1
I am receiving the following error below when running gdalwarp to crop an input orthomosaic in the NAD83(2011)-Alaska Zone 1 CRS. The command still runs and the output cropped TIFF file renders fine ...
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Using ERDAS Imagine 2020 orthophotos
I am dealing with how to figure it out how to export an orthomosaic from my Agisoft Metashape because when I did the merge chunks there. When you merge there, it doesn't provide what I need because of ...
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Combining orthophoto and DEM to export xyz-CSV
I have a georeferenced orthophoto and a DEM as tiff-file. For my further workflow I want to export x,y,z (x,y from the orthophoto and z from the DEM).
I already managed to create a point layer and ...
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Co-registering multiple temporal orthomosaics?
I have multiple (19) orthomosaics of the same approximate region taken regularly over the course of a couple months with a UAV. Some, but not all, include ground control points we placed in the scene....
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Rotating ortho-satellite imagery so that square polygon perpendicular to the viewer
I'm trying to figure out how to rotate this satellite geotiff so that the rooftop polygon would appear as square as possible to the viewer rather than a diamond shape. See example below.
How to ...
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Where can I find decent resolution (5m ish) night time orthophotography/satellite imagery data for Ireland?
Anything I've found so far has been incredibly granular. I need a resolution which is fine enough to see general lighting footprints for motorway junctions.
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Light normalization of Orthophotos to increase comparability
I would like to work with the RGB-values of different orthophotos. Now I noticed that the light conditions are not the same in the different orthophotos. I was wondering if there is a sound way to ...
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Method in QGIS to classify veg from HiRes geotiffs created in Pix4D?
I have 10 2D geoTIFF orthophotos (~2GB each, ~3km2 each, all 4.2cm/pixel) that I generated from Vis RGB 12MP images in Pix4D for a desert vegetation survey over 30km2 for a development. I need to ...
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Storing non-orthorectified images in GeoTIFF
I'm reading GeoTIFF and GDAL documentations and I'm trying to understand what type of transformations are supported.
GeoTIFF documentation says you can use ModelTransformationTag to define a ...
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Aerial mosaic of thermography
I have a large set of aerial images (thermography) some of them are very tilted due to the airplane turning. I want to merge all the images into a unique orthorectified image. I have not the GPS ...
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qgis2threejs and large area
In my project I am trying to create a model of a large territory (10 kilometres square area) through the use of Threejs plugin to be able to export it in glTF.
By opening the DTM and the ortho on ...
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All layer in QField-project are greyed out and not visible
I wanted to create a QField project with orthophotos from different years to digitise a how a river basin changed due to erosion. However, when I load the project in QField onto my iPad it only shows ...
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Incorrect NDVI range results in ArcMap
I am creating NDVI from multispectral orthoimagery for multiple years. For the majority of the data, results from NDVI using the Image Analysis window range between -1 and 1 as expected.
However for ...
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Georeferencer producing unusable results
Using QGIS 3.26.1 Buenos Aires.
I am georeferencing orthophotos produced with an RTK drone and Reality Capture software. These are typically a few centimetres out of alignment with one another. ...
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Automated aerial image registration/GCP definition in QGIS ecosystem
I have a couple of aerial orthos from different sources and different years (governmental agencies, UAV mapping, etc). Unsurprisingly, they are not perfectly aligned, in a nonlinear way (i.e. it's not ...
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Pointcloud to RGB raster (orthomosaic)
I am trying to create an orthomosaic for as cheap as possible. The project I am working on has absolutely no budget and the methods I use need to be easily used by someone who has no experience in GIS/...
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Weird issue in orthophoto of canpy in rough terrain
After postprocessing drone imagery of a forest area in rough terrain, I had a weird issue such as in the images below.
The effect is like the cropping of trees following the DSM.
If you have ...
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gdalwarp on County-wide mosaic or COG takes forever or seems to hang
I am creating Cloud Optimized GeoTIFFs using gdal from a folder of TIFF files in GDAL for an entire county. After creating a mosaic of these files (in EPSG:6551) using gdalbuildvrt I can create a COG ...
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Area measurement validation: ellipsoid vs geoid
I try to validate area measurements on orthomosaics using objects of known size on the ground. I'm working on centimeter level measurements.
As far as i understand an orthomosaic in WGS 84 is ...
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Adding ortophoto to map through hyperlink in ArcMap
I would like to add layers (more specifically Orthophotos) through the hyperlink function in ArcMap 10.3.
With hyperlinks it is possible to add script (VBscript), documents and URL.
If I add the ...
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Calculating exterior and interior orientation of any drone without camera calibration
I have a drone, how can I find the projection matrix without calibration?
Since the drone has a GPS, I know some angles and the distance between the two photos in meters. I also know the formula of ...
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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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Splitting GeoTIFFs
I have three different GeoTIFF orthophotos I am trying to tile (the editing program I use can't accept the GeoTIFFs as is), and I would like to retain the geographical information. Can someone offer ...
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How to retrieve GIS data in Multiple Orthophoto at point level
I have been using a python script that can read Data from Orthophoto(*.tiff) of size 300Mb-2Gb. But this is taking 32s per request of lat-long, which is not ok.
I have different Orthophotos with ...
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Grass Gis: What is the meaning of a TARGET LOCATION?
I am attempting to follow a guide on creating ortho-photos in Grass GIS, available here:
https://grassbook.org/extra/sample-chapter/
The chapter suggests that a separate cartesian LOCATION should be ...
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Converting a drone orthophoto saved as KMZ to TIFF in QGIS
Dragging a drone-obtained orthomosaic image saved as a KMZ file (167mb) into QGIS results in the image being very poor resolution. But when KMZ file is loaded into Google Earth, it's very high ...
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