7

Set your project CRS to a pacific centered CRS like EPSG:3832 or EPSG:8859. Your map canvas with basemap should than look like in screenshot 3 below. Than georeference your map using the same CRS for transformation settings (screenshot 2). Once you georeferenced the image, you can change your project CRS back to the one you used before or re-project your ...


6

You can create an external world file, which provides the georeferencing information for the raster image you export. ... # save the image img.save('/home/bera/Desktop/test_render.png') # world file content pgw_content = QgsMapSettingsUtils.worldFileContent(ms) with open('/home/bera/Desktop/test_render.pgw', "w") as f: f.write(pgw_content) ...


4

I found that both datasets should be in the same coordinate system, epsg:25832. That solved the problem. This GDAL command solved the problem: gdalwarp -t_srs epsg:25832 oJostedal_k3_2016_ps.tif oJostedal_k3_2016_ps_25832.tif


4

To go from image coordinates to geographic coordinates, get the geotransform using img.GetGeoTransform(), then the transform is as follows: gt = img.GetGeoTransform() x_pixel = cX y_line = cY x_geo = gt[0] + x_pixel * gt[1] + y_line * gt[2] y_geo = gt[3] + x_pixel * gt[4] + y_line * gt[5] Source: https://gdal.org/tutorials/geotransforms_tut.html#...


4

The original scan of the map can be found here: http://legacy.lib.utexas.edu/maps/ams/india/nc-43-03.jpg I have enlarged the details on central bottom of the map The CRS of the blue lines can be identified as EPSG:24374, Kalianpur 1880 / India zone IV The map projection proper is transverse mercator, likely also on Kalianpur 1880, eyeballing the central ...


4

Yes, just say that you work in meter, and the resolution of your png is 25 cm, and your png has no rotation. So your pgw file looks like that: 0.25 0.00 0.00 -0.25 2539000.049999999813735 1153999.949999999953434 Save it as name_of_your_png.rtf and change the extension to pgw. So it means: Line 1: resolution in x (25 cm) Line 2: no rotation in y Line 3: no ...


3

Python and GDAL provide this functionality. Have a look at GDAL.GCP for adding the ground control to the TIF. See this Stack Exchange example, the GDAL GCP class in the GDAL Python API, and this well documented link to get you started. I see that there is also a Java/GDAL bindings.


3

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 cropping. In addition, there is post-processing to remove distortion. Therefore the published focal length, sensor size, and/or angular field of view specs need ...


3

I have just updated the QGIS docs (v3.16) with more comprehensive information on this. See https://docs.qgis.org/3.16/en/docs/user_manual/working_with_raster/georeferencer.html#available-transformation-algorithms The new docs capture some of the information from prior answers to this question, as well as comments/experiences from elsewhere. In particular, ...


3

OpenCV is a powerful and useful tool for 'contour detection' and convert them in vector layers. However, they are produced in image coordinates (i, j indices); not in map coordinates. For overcoming this issue you need to have your binary mask with buildings' footprints georeferenced by using your specific reference building. With your data (center of the ...


3

Double-check that the PDF does not includes a coordinate reference system (CRSinformation). You may have a geo-spatial PDF which includes a coordinate reference system but that may not be obvious to you. ArcGIS Desktop does not consume geo-spatial PDFs but there are tools to convert those to geoTIFFS. See PDF To TIFF. If that is the case, do the ...


3

In surveying, we called "the world file" the georeferenced portion of a file. It tells the GIS or mapping software where the file is located and at what scale to display it at. If a CAD drawing/file is georeferenced, it means this location and scale data is embedded in it and can be used to place its contents on the map appropriately. DXF file: ...


2

In Photoshop (or other image package) crop to the actual map export to tiff In QGIS load the crop tiff into the georeferencer. Using Linear (to create a wordfile) 4 GCP points (make sure residual error is kept to a minimum) georefence the tiff reload into QGIS with the world file 50.23252856955928536 0 0 -50.00689541422411111 1427952.16767665231600404 492023....


2

It is normal that your map looks streched: that what Island looks like if you set the project CRS to EPSG:4326 (check it with a basemap like OpenStreetMap). If you change the project CRS to another value (like WebMercator EPSG:3857), everything will be fine. Your "streched" georeferenced image will be transformed (again) to fit the project CRS. See ...


2

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 such as PILLOW. Some data may be stored in the XMP tags. XMP tags can also be extracted from images using this library. I have developed Python code to do ...


2

It's always a challenge to help people with site-specific installation issues, and it's perhaps not best suited to this forum (gis.stackexchange.com). But let me try to give a generalizable answer that will hopefully benefit you now and others later. QGIS exists as part of an ecosystem of open-source geospatial tools. QGIS displays, edits, and does ...


2

Both the four GCP images and the six GCP images display with an affine transformation in ArcGIS Pro 2.7, QGIS 3.4, and QGIS 3.10 on Windows 10. QGIS 3.18 Ubuntu Linux v20.04 is not displaying the six GCP images correctly. The 6 GCP images displayed with the upper left image corner at the equator/greenwich with no rotation, scaling, or resizing. The problem ...


2

Short answer: use GDAL tools to extract lat and long data from an .nc file. Merge it with the data from any band you want to see to make an x,y,z dataset. Convert the irregular x,y,z data to a shapefile and apply a CRS. Grid the shapefile at desired resolution. The lat/long data are not regularly sampled, so the data can't be loaded as an XYZ raster ...


2

The CAD drawing seems to use a local coordiante system with meters or feet as units. Furthermore, the map is rotated, because 56th East Street stretches East-West and Drum street North-South. Best choice would be to ask the author of the drawing what coordinate origin they have used, and what units of measurement. A brute force method would be to ...


2

There is a tool called "Composite Bands" https://pro.arcgis.com/en/pro-app/latest/tool-reference/data-management/composite-bands.htm that will stack your single bands into a multiclass raster. Run this tool. Then georeference your image. To unstack them just right-click on the individual band in the catalog window, click export, and then "...


2

It looks like your coordinates need to be converted. The example coordinates you provided are not standard latitude/longitudes. Latitudes have a maximum of +/- 90 degrees (at the poles) and longitudes have a maximum of +/- 180 degrees (at the anti-meridian). Your numbers are in the hundreds of thousands, which makes me wonder if they are in some UTM ...


2

As it says in the video at about 1:40 the EPSG used here is 24879, but as @Ian Turton points out, that does not mean, that yours should be the same. To change the coordinates in your system you have to go to Transormation Paramters (via settings in the Georeferencer) and set the Target SRS to the correct SRS (what ever your data have).


2

Looks like you really want to use the -a_ullr argument to set the four corners of the image. I have a png with no coordinate info, and if I do this: $ gdal_translate -a_srs epsg:4326 -a_ullr 49.01991 65.28265 53.18008 63.48401 exceed4.png exceed4.tiff I get a tiff with these coordinates: Corner Coordinates: Upper Left ( 49.0199100, 65.2826500) Lower ...


2

You can use gdal_translate (https://gdal.org/programs/gdal_translate.html) with parameter -a_ullr to georeference your image. In the example below I'm georeferencing a PDF file: gdal_translate --config GDAL_PDF_BANDS 4 --config GDAL_CACHEMAX 1024 -co NUM_THREADS=ALL_CPUS -co COMPRESS=DEFLATE -co ZLEVEL=9 -co PREDICTOR=2 -co TILED=YES -a_srs EPSG:31255 -...


2

You could do something like this in python using rasterio. UAV_image = rasterio.open('UAV_image.tif') new_tif = rasterio.open('new.tif','w', driver='Gtiff', height = UAV_image.height, width = UAV_image.width, count = 1, crs = UAV_image.crs,...


2

If you have an accurate location of your balloon, as well as accurate yaw, pitch, and roll (YPR) for the camera, calculating the direct vector between the lens and the ground is a matter of trigonometry. With that vector, an elevation model, and the camera specs, you can calculate the expected footprint of your image. You can look at this description from ...


2

Your CAD drawing is a detailing some features or object distributed in Euclidean space. That drawing can reference some arbitrary datum like 'paper coordinates' (0, 0). That drawing can also be georeferenced to use the datum of a coordinate reference system datum like (0, 0) UTM. In the case of the UTM georeferenced drawing your features would have ...


2

The look of the georeferencer may have changed since the tutorial was written. No automatic prompting happens but user must load the image and open the raster settings Press the globe icon and select the coordinate reference system


1

Looking at the source code for qgsgeorefmainwindow.cpp, function QgsGeoreferencerMainWindow::calculateMeanError in particular, the calculated "mean error" is the sum of the squares of the residuals divided by the number of points minus the minimum points required to specify the transform, i.e. adjusted for the degrees of freedom. I haven't redone ...


1

This is caused by trying to read in a "normal" tiff file with no spatial data in it. GeoTools is trying to find the required parts of a GeoTiff and not finding them. You should read in your tiff using BufferedImage image = ImageIO.read(inputFile); and you can then create a coverage using GridCoverage2D gc = gcf.create("name", image, ...


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