22 lines
1.1 KiB
Text
22 lines
1.1 KiB
Text
A file format and library for storing and rapidly accessing point
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cloud data, in particular LIDAR data.
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GeoHashTree organizes points into a tree structure for fast spatial
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access. The tree structure itself encodes the significant bits of
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at each node, so child nodes can omit them. The result is a smaller
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file than if all the points were stored with full precision. Each
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node includes statistical information about the children below (e.g.
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average/median Z value) permitting fast overview generation.
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Additional attributes are attached to the tree at parent nodes,
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below which all children share the attribute value. This reduces
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duplicate data storage further.
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The advantage of a GeoHashTree file over a LAS file is fast access
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and filtering, since the tree encodes useful information at each
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node to speed searches over the full set of points in the file.
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LASZ zipped files can be smaller, but will be less efficient at
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overviews, searching and sub-setting. GHT is a good working format
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for applications that will be filtering and querying large sets of
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LIDAR data.
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WWW: https://github.com/pramsey/libght
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