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