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@@ -6,27 +6,23 @@ based on spatial dependence matrices at 0, 45, 90, and 135
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degrees for a <em>distance</em> (default = 1).
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<p>
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-The output of <em>r.texture</em> can be used as additional input for
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-image classification or image segmentation (object recognition). The output
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-of <em>r.texture</em> can thus be used as input to supervised classification
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-algorithms such as <a href="i.maxlik.html">i.maxlik</a> or
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-<a href="i.smap.html">i.smap</a>, or for characterizing objects resulting
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-from <a href="i.segment.html">i.segment</a>, for example as one of the
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-raster inputs of the
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-<a href="https://grass.osgeo.org/grass70/manuals/addons/i.segment.stats.html">
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- i.segment.stats</a> addon.
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+Texture is a feature of specific land cover classes in satellite imagery.
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+For example an inland water body will generally have a quite homogeneous
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+texture (unless strong winds create many waves), but mixed forests or urban
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+areas will have more heterogeneity amongst neighboring pixels. Obviously,
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+this is highly dependend on the resolution of satellite imagery (also see the
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+discussion of scale dependency below).
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<p>
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-<em>r.texture</em> assumes grey levels ranging from 0 to 255 as input.
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-The input is automatically rescaled to 0 to 255 if the input map range is outside
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-of this range.
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-
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-<p>
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-In order to reduce noise in the input data, and to speed up processing,
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-the input map it is recommended that the user recode the data using
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-equal-probability quantization. Quantization rules for <em>r.recode</em>
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-can be generated with <em>r.quantile -r</em> using e.g 16 or 32 quantiles
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-(see example below).
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+The output of <em>r.texture</em> can thus constitute additional variables
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+usable as input for image classification or image segmentation (object
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+recognition). It can be used in supervised classification algorithms such
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+as <a href="i.maxlik.html">i.maxlik</a> or <a href="i.smap.html">i.smap</a>,
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+or for the identification of objects in <a href="i.segment.html">i.segment</a>,
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+and/or for the characterization of these objects and thus, for example, as one
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+of the raster inputs of the
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+<a href="https://grass.osgeo.org/grass70/manuals/addons/i.segment.stats.html">
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+ i.segment.stats</a> addon.
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<p>
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In general, several variables constitute texture: differences in grey level values,
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@@ -41,6 +37,15 @@ are defined in degrees of east and they increase counterclockwise, so 0 is
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East - West, 45 is North-East - South-West, 90 is North - South, 135 is
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North-West - South-East.
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+<p>
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+<em>r.texture</em> assumes grey levels ranging from 0 to 255 as input.
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+The input is automatically rescaled to 0 to 255 if the input map range is outside
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+of this range. In order to reduce noise in the input data, and to speed up processing,
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+it is recommended that the user recode the data using equal-probability quantization.
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+Quantization rules for <em>r.recode</em> can be generated with <em>r.quantile -r</em>
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+using e.g 16 or 32 quantiles (see example below).
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+
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+
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<h2>NOTES</h2>
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<p>
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Moritz Lennert