reads LIDAR data in the LAS format and computes statistics that tell us whether the precision “advertised” in the header is really in the data. Often I find that the scaling factors of a LAS/LAZ file is miss-leading because they make it appear as if there was much more precision than there really is.
To judge that we compute coordinate difference histograms that allow you to easily decide whether there is artificially high precision in the LAS/LAZ/BIN file. This may have been introduced during LAS conversion by “upsampling” to a higher precision “to play it safe”.
Once you figured out the “correct” precision you can also use this tool to resample the LAS/LAZ file to an appropriate level of precision. A big motivation to remove “fake” precision is that LAS files compress much better with laszip without this “fluff” in the low-order bits.
For example I find “fluff” in those examples:
- Grass Lake Small.las
- MARS_Sample_Filtered_LiDAR.las
- Mount St Helens Oct 4 2004.las
- IowaDNR-CloudPeakSoft-1.0-UTM15N.las
- LAS12_Sample_withRGB_QT_Modeler.las
- Lincoln.las
- Palm Beach Pre Hurricane.las
There are also options to look at the ‘-gps’ time and the ‘-rgb’
colors in the same manner. You can change the amount of lines
that are output per statistic with ‘-lines 30’.
See README file for more information.