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9

ESRI has a pretty good help section on LiDAR (below). For more formal details on LiDAR, I would recommend the following books: Topographic Laser Ranging and Scanning: Principles and Processing Airborne and Terrestrial Laser Scanning Remote Sensing and Image Interpretation LiDAR Laser Returns Laser pulses emitted from a lidar system reflect from ...


3

Yes, there are free object-oriented (segmentation) software available. A few that come to mind are Spring, ITK, Orfeo toolbox and GRASS GIS. I would however point out that image segmentation is a poor direction to peruse when trying to model fractional cover. A segmentation algorithm is designed to minimize within unit variance and maximize between unit ...


2

This is not exactly the answer to your question, but rather a suggestion. For RS, I would not use QGIS as a core software, because it is more oriented for GIS (even if it includes many tools). I suggest that you have a look at GRASS 7 (the new GUI is a true step forward). I don't have a look of experience because it is new, but I got some feedback and I've ...


2

Just use the ArcGIS raster calculator with a CON statement. CON(("h2005" - "h2015") >= 30, 1, 0) This will result in a binary raster where [1] represents differences of >= 30m and [0] no change at this threshold. And yes, set your analysis environment for extent and snap raster.


2

I have attended training in use of the Semi-Automatic Classification Plugin for QGIS. From what I could see it could be what you are looking for. The whole rig is available for free, so money should not be an issue. Admittedly I am no expert in these tools, but the author says it includes several classification algorithms (Minimum Distance, Maximum ...


2

As mentioned by @nicholaschris, Zhu et al's paper is nice, and they have a tool associated with it. Note that the shift is a function of 1) the position of the sun (doesn't vary on one image), 2) the position (XYZ) of the cloud and 3) the elevation of the ground (2 and 3 do vary). So that a unique shift could not be enough. To answer the question with ...


1

Use the Layer Stack tool in reverse by using your 11 band stack as the input and selecting only the bands you want in the output. For example, in the attached screenshot I added bands 1, 2, 3 to the stack (omitting band 4).


1

As @user30184 says, gdal is just reading the values of your raster band, but you should be able to know the wavenlenght of each band based on the metadata (information you should get about the data). the two values returned by "ComputeBandStats()" will be the mean and standard deviation of the values in your bands. If the mean value is between zero and ...


1

The picture below from Fernandez-Diaz (2011) might help complementing Aaron's answer. Lidar returns are discrete observations* recorded when a laser pulse is intercepted and reflected by targets. Multiple returns derive from one laser pulse intercepting multiple targets (e.g. a top of a tree, its branches, and the ground). *such as coordinates x, y and z; ...


1

The Cal-Atlas site has 2012 NAIP R,G,B,NIR quarter-quad tiffs available for download. The USDA-APFO provides a REST ArcGIS webmap service which now contains the NIR band. To use this service you will need to add a GIS Server in ArcGIS. 1) Open ArcCatalog and in the Catalog Tree select "GIS Servers" 2) Double click "Add ArcGIS Server" 3) In wizard select ...


1

Not exactly "high-resolution," but the price is right. Esri's World Imagery map service presents satellite imagery for the world and high-resolution imagery for the United States and other areas around the world.


1

I just found a proceeding paper by Maurice Schönert et al. (2014) in which they derive Tasseled Cap Coefficients for the RapidEye sensors. I haven't tested it myself, but it looks promising.


1

The short answer is that you can't. The documentation says: The Advanced Wide Field Sensor (AWiFS), on-board IRS-P6 operates in four spectral bands in green (0.52-0.59µm), red (0.62-0.68µm), near infrared (0.77-0.86µm) and short wave infrared (1.55-1.70µm) Since the data does not have the regular 3 bands, you cannot get a True color composite of ...


1

Landsat 8 is now being digested by AWS. There is a standard directory structure and the data can be accessed via an http or through the AWS commandline interface. While this not an ftp interface, it will be quite easy to batch download in a scripting language.



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