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I'm trying to georeference and later obtain spectral bands of a given specified region but I can't find a way to georeference it because its difficult to find the control points in the images acquired due to their high pixel to meter ratio.

closed as unclear what you're asking by Aaron Feb 20 '17 at 6:37

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    Got example data files? Normally satellite data is georeferenced so has it been lost somewhere? – Spacedman Jul 20 '16 at 20:45
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Don't worry about GeoREferencing. Just add a WMTS from many different providers of the Landsat 7 or 8 data.

You can access Landsat imagery from ESRI or from the US Navy Research Lab or from the USGS

http://geoint.nrlssc.navy.mil/nrltileserver/wmts Landsat7

http://earthexplorer.usgs.gov/

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If you want to georeference the Landsat images themselves, they should have a native georeference so you might have no correct data or files. If you want to georeference other data (another raster perhaps?) using the Landsat images as a reference map to extract GCP, thats a whole different case: remember that Landsat images have a rather large pixel size (15m pan, 30m multispectral) so accuracy of ground control points for georeferencing is rather low. Also identifying small features on a Landsat image could be impossible or extremely challenging (due to pixel size). Very detailed maps of small areas for example cannot be georeferenced based on a Landsat image or similar sensor. Prominent features such as main roads and intersections, built up areas, man-made structures (e.g. port facilities) and large streams/rivers (warning: rivers and streams with changing fluvial features with time - e.g. meanders, avulsion, deltas should be avoided in images with more than one year apart) are ideal GCP for Landsat images but not small features as individual building, small roads or property boundaries that cannot be clearly seen in those images.

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I would recommend the Semi-Automatic Classification Plugin. Go to plugins -> Manage and Install Plugins -> type in 'semi-automatic classification' and you should be able to install it. The tool can be quite intimidating but it allows you to generate 'regions of interests' (e.g. from shapefiles), set different false colour band combinations, and even download landsat images directly if you fancy!

Semi-Automatic Classification Plugin

As a start, I would recommend you watch the video at http://fromgistors.blogspot.com/p/semi-automatic-classification-plugin.html to get a feel for how to use the tools. Then you can work out the Landsat stuff by following this tutorial. Let me know how it goes.

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ESRI has many services for Landsat http://www.esri.com/software/landsat-imagery/image-services All of them can be accessed via web, mobile and desktop clients here's an example URL. http://landsat2.arcgis.com/arcgis/rest/services/Landsat8_Views/ImageServer

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    Instead of answering again, edit your previous answer to add more information – Midavalo Sep 18 '16 at 5:34

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