39 lines
1.4 KiB
HTML
39 lines
1.4 KiB
HTML
---
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layout: example.html
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title: Region Growing
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shortdesc: Grow a region from a seed pixel
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docs: >
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<p>Click a region on the map. The computed region will be red.</p>
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<p>
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This example uses a <code>ol/source/Raster</code> to generate data
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based on another source. The raster source accepts any number of
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input sources (tile or image based) and runs a pipeline of
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operations on the input data. The return from the final
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operation is used as the data for the output source.
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</p>
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<p>
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In this case, a single tiled source of imagery data is used as input.
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The region is calculated in a single "image" operation using the "seed"
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pixel provided by the user clicking on the map. The "threshold" value
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determines whether a given contiguous pixel belongs to the "region" - the
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difference between a candidate pixel's RGB values and the seed values must
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be below the threshold.
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</p>
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<p>
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This example also shows how an additional function can be made available
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to the operation.
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</p>
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tags: "raster, region growing, maptiler"
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cloak:
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- key: get_your_own_D6rA4zTHduk6KOKTXzGB
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value: Get your own API key at https://www.maptiler.com/cloud/
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---
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<div id="map" class="map"></div>
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<div>
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<label class="input-group">
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Threshold:
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<input id="threshold" type="range" min="1" max="50" value="20">
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<span id="threshold-value"></span>
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</label>
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</div>
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