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As far as I know there is indeed no pre-implemented module for the automated conversion of SPOT DN values to reflectance. If you insist on doing it in ERDAS Imagine, then you should use the Spatial Modeler for the conversion. Maybe this might help you getting started. You need to look up the gain parameters of the SPOT sensors in order to apply the right ...


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I assume you are going to apply an automated classification algorithm to detect roads in the imagery. I would recommend two products: 4-band NAIP imagery at 1m spatial resolution and Landsat 8 (15m (panchromatic)- 100m (SWIR))--both of which are free and available from Earth Explorer and from a variety of state web sources. The 30m Landsat data would be ...


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Your script is configured to take a point shapefile of training data and use that to train a Random Forest classifier. The screenshot shows the form the shapefile attribute table needs to take in order to be used as a training set. The important fields here are 1) the XY coords, 2) the pixel values for each band at that XY coordinate, and 3) the class of ...


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NASA hosts a paper that can be found here which gives detailed answer to your title question. In particular page 2, paragraph 3 and page 21 starting at paragraph 2. The short answer is no, SRTM data is not necessarily bare-earth measurement and may be tree canopy. However, radar can potentially partially penetrate tree canopies, so the given height might not ...


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I'm not an SRTM expert, not even an SRTM novice. http://www.opendem.info/technology.html provides a nice methodology for correcting for tree canopy height. So, no, it does not appear that the SRTM data is corrected. However, there are ways to do such a thing. Good Luck.


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I don't know about any European database of ready-made high resolution NDVI, but it's relatively easy to create it from raw Landsat imagery in 30m resolution. Access to the Landsat archive is free of charge (only registration needed) via EarthExplorer web service link. In the Data Sets tab, expand "Landsat Archive" list and check L8 checkboxes for ...


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This depends what you are trying to do with the data, i.e. what really matters to you? Question is which one you need more, high spatial or high temporal resolution since it's hard to get both. In high temporal resolution I think the MODIS or AVHRR products mentioned above will be the choice, but if high spatial resolution is a must, then I think Landasat 8 ...



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