The essential utility of intelligent extraction.
CleverExtract is a standalone tool that is available independently from Terasurf.
You have too big “3D” datasets (irregular survey points or gridded data) in which the 3rd dimension (the “Z”) means elevation, depth, temperature, pressure, or any other parameter whatever the unit is (decibel, volt/meter, etc.). The data is in any projected or geographical coordinate system.
CleverExtract retrieves from your datasets the minimal distribution of irregular points which then allows for the construction of a digital model using Delaunay triangulation in accordance with the input data and within a given vertical tolerance. In case the 3D data comes from LIDAR, bathymetric or land surveys, we can speak about height or depth tolerance.
The essential tool for a clever extraction
A very simple user interface
The CleverExtract interface is particularly simple:
It is also possible to produce the result as a TIN (Triangulated Irregular Network):
CleverExtract allows to parameter the tolerance according to the Z and to limit the extraction within a given vertical range:
In blue: the input points – In red: the retrieved points with tolerance based on elevation.
Extraction with tolerance based on depth (shallow water studies).
CleverExtract allows for the simultaneous selection of several files in order to process automatically, for example, a batch of adjacent grid squares:
The processing of a set of 172 ASC 1000 X 1000 files to a resolution of 1m: CleverExtract has generated sufficient files to retrieve 4,893,423 points in just 4min45 (with a height tolerance of 25cm).
Due attention user interface
In the case where the input data is a dataset of gridded data files constituting a series of adjacent tiles, CleverExtract allows to extract also the boundary of each tile in the form of points or break lines. It is then possible to rebuild a model from the retrieval that complies scrupulously with the specified tolerance even over the tiles boundaries.
CleverExtract takes into account the random triangulation when the triangles share a same circumscribed circle, a case that happens very often when the input is gridded data. Doing so, CleverExtract ensures that the Delaunay triangulation produced then by any software will scrupulously comply with the specified tolerance.
Two possible triangulations: triangles sharing a same circumscribed circle.
All the points retrieved by CleverExtract correspond most rigorously with the original values. None of the output points is issued from interpolation.
Using the GDAL library, CleverExtract allows to read the gridded data ASC format, the XYZ and CSV formats, as well as the vector formats SHP, TAB, MIF/MID, DXF, DGN, GMT, SGF and OBJ. CleverExtract allows for the production of files in similar point and vector formats.
Performances
The input limitations are the followings:
- Only limited by memory for irregular data files (about 6 Gb for 50 millions points)
- 1 billion of pixels per gridded data file
From a 1000 X 1000 ASC grid to a resolution of 1m, the following table indicates the number of points retrieved and the processing time for the following height tolerances:
From an XYZ file of 426 658 points, the following table indicates the number of points retrieved and the processing time for the following height tolerances:
