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7

The following is basically quoted from the book: "Mastering QGIS" by Kurt Menke, Luigi Pirelli, Richard Smith Jr & John Van Hoesen on page 199: mapX and mapY are the Destination Coordinates. pixelX and pixelY are the Source Coordinates. enable has a boolean value where 1 means it will be used in the transformation; 0 means it will not be used. Hope ...


4

The simplest way to run your analysis (without trying to define your actual inputs) is to do some basic raster algebra. Have a go with the raster calculator: https://docs.qgis.org/2.8/en/docs/user_manual/working_with_raster/raster_calculator.html You can build up some other vector layers too, such as 'distance to waterbody' as a distance raster. To ...


3

If you load an unreferenced raster into the georeferencer, the question for the CRS is surely useless. The referencing assings values of pixel/line to target coordinates, so the source CRS does not play any role. The target CRS however is important, it depends on the way you are doing the georeferencing. You have lat/lon grid lines imprinted on the map, ...


2

When modelling the distributions of species, may they be animals or plants, fuzzy overlays are typically used. For an introduction into habitat suitability modelling, I suggest you take a look at GISLounge - Overview of Fuzzy Logic Site Selection in GIS. As Michael has already pointed out correctly, you will need more than one criterion (in your case ...


2

The columns mean: Geographical easting/longitude Geographical northing/latitude Location of the ground control point in image pixel space from left to right Location of the ground control point in image pixel space from top to bottom Boolean selection if the GCP should be used (1) or not (0) in computing The anchor point in the image space is at top-left ...


1

A map is not georeferenced. Shapefiles and feature classes (s/fc, for short)) can and usually do have a coordinate system, either geographic or projected. Other items, typically imagery such as a jpg or CAD data, are then georeferenced to the s/fc. Basically, georeferencing refers to the process of 'rubbersheeting' the image to known reference points in the ...


1

If the file is a tif, you can add transparency to it, either by adding a transparency channel, or with additional NODATA values. For the first solution, you might clip your data by a polygon layer of the red line. For the second solution, you can use the information tool on the raster layer, note the raster value in the black and white areas you want ...


1

I seem to have found the cause of the problem. It seems if I rotate an image using windows photo viewer prior to bringing it into ArcMap and georeferencing it, this will cause the problem (for me at least!)



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