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5

I think there may be an issue with your app_code and app_id. I was able to add that service as an XYZ Tile in QGIS using my App_id/App_code, but not with yours. Is yours restricted to a domain? And: If you are adding this as an XYZ Tile, you have to put the z,x,y parameters in place of actual values: https://2.aerial.maps.api.here.com/maptile/2.1/...


4

The Rasterio Plotting documentation describes how to visualize multiband imagery. For example, using 4-band NAIP imagery: import rasterio from rasterio.plot import show src = rasterio.open("path/to/your/image/m_3511642_sw_11_1_20140704.tif") show(src) To visualize specific band combination use the following approach (source). In this case, I am creating a ...


3

It looks like different images to me... On the right side, there is much less green a much more "something" that looks like water. I think that image was acquired with different conditions (during floods?) Images from same sensor can substantially differ in quality, based on weather, time of day, angle of camera and so on... As another one sugestet, try to ...


2

MODIS imagery is publicly available via satellite imagery service called LandViewer. You can download it with ease via the toolbar on the right or use dozens of tools for image analysis directly on the platform. Besides that there are already ready-made tools for obtaining multispectral indices, flexible processing of data on AOI, elementary clustering, ...


2

Unfortunately, there’s no such thing as live satellite imagery yet. Space agencies and commercial imaging companies are trying to reduce interval between image acquisition and delivery, but the most frequently updated imagery in free public use is still the one from weather satellites. You may choose to buy commercial images from DigitalGlobe, Airbus, ...


2

First - the overly broad answer. Yes - objects shift over time due to continental drift. However, that is not what you are seeing in your data (I hope, for your sake, as that would likely result in some massive earthquakes in your area). What you are likely seeing is inaccurate georeferencing. Highly accurate and automated georeferencing is not easy. The ...


2

Basically, what you need is to compute the RMS of the positionning error. This type of analysis requires a manual input of points that you should place on your satellite image where you SEE that it should be according to the location on the ground where you took the measurement. So the procedure in ArcGIS would be : 1) create a point feature class 2) In an ...


2

There are lots of places to download GIS data and imagery around the web but they can be tricky to find. Earth Explorer is a good option that searches by location, time, and data set, giving you access to lots of imagery for free. This includes imagery from NAIP / NAPP, which is probably the most applicable to your project. https://earthexplorer.usgs.gov/ ...


2

To read an image using gdal as a numpy array you can use the following two lines: ds = gdal.Open('path_to_img', 0) arr = ds.ReadAsArray() However, you can run into a MemoryError if your image is too large. Depending on your needs, you can read one chunk of the image at the time. The ReadAsArray() method can take four useful arguments to accomplish this: ...


2

I'd take a lookt at Planet. They offer three different resolutions (1, 3 and 5m). You can get a free-trial and check if it fits your needs. For the costs, maybe check this conference paper that does a benchmark of different satellites or this pricing information for reference.


1

This report uses the Forest Discrimination Index (FDI), described by Bunting and Lucas (2006) to create a mask. Essentially, the FDI for worldview2 is NIR2 - (RE + Blue), or band8 - (band6 + band2). You have to play around with the threshold, but here is a function I used in arcGIS Pro. One of the problems is that it will cut out buildings, roads, etc. For ...


1

Create layer group, add image layers to group and then add layer group to map: var imageOverlays = L.layerGroup(); L.imageOverlay(priorycourt, imageBounds).setOpacity(0.75).addTo(imageOverlays); L.imageOverlay(ipswich3a, imageBounds).setOpacity(0.75).addTo(imageOverlays); imageOverlays.addTo(map); or var priorycourtLayer = L.imageOverlay(priorycourt, ...


1

Yes. Your understanding of the formula is correct. TOA_radiance = DN * absCalFactor / effectiveBandwidth This is the formula that you need. However, as you likely already know, your example value of 4 is a rather unrealistic value. Values around 200 to 400 are more normal.


1

I think you are getting wrong altitude values not because the focal distance. The altitudes computations depends of some factors: Numbers of photos for intersection calculus: If you have few photos for each point, errors in the intersection will be absorbed in Z coordinate. Number and distribution of GCP's: The ground control points must to be correctly ...


1

I thought that I had seen a new feature in ArcGIS Pro 2.3 to be able to designate a polygon feature to act as a graphic clip on a map frame. However, when I looked just now I found that it was not there. What you can do is to digitize a polygon to act as a graphic clip on a map frame and this is described in the Modify a map frame help: On the Insert ...


1

Saving imagery from webmapping services like those you mentioned sounds more like a webscraping task: Open the desired website, then open the inspection tool of your browser (ctrl+shif+c or ctrl+shift+i for firefox) and check in the network tab for image-tile-urls like this: https://maptiles.finncdn.no/tileService/1.0.3/norortho/9/265/145.png Further ...


1

You could reference About automatic vectorization Automatic (batch) vectorization can involve a series of procedures to achieve an acceptable raster-to-vector conversion. It can be as simple as executing one command to generate the vector features. Depending on the state of the input raster data you are working with, the vectorization process varies. This ...


1

I have gone through some more answers and found this nice stuff. Here it is: https://github.com/publiclab/Leaflet.DistortableImage


1

For those looking for the new atlas site to get NAIP imagery..... hot off the press.... http://gisarchive.cnra.ca.gov/iso/ImageryBaseMapsLandCover/NAIP/


1

You may download such date from a service called LandViewer. All the satellite data is free to use and easy to find thanks to the convenient search interface, which reduces time needed to find right image data. LandViewer has a list of default band combinations and spectral indexes for extracting information based on spectral signatures. You can also create ...


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