LASzip

LASzip is an open-source lossless compression library and format for LiDAR point cloud data. It compresses LAS files into LAZ files, reducing storage requirements while preserving all original measurements. The project was initiated by Martin Isenburg as part of the rapidlasso project in the late 2000s and has since become the de facto standard for compressed LAS data.

LAZ files produced by LASzip store the standard LAS point record fields, including X, Y, Z coordinates, intensity, return number, number of returns, classification, scan angle, user data, and point source ID, along with any extra bytes. The compression is lossless, achieved through delta coding and other entropy-coding techniques optimized for LiDAR data, enabling exact reconstruction of the LAS file when decompressed. LASzip supports multi-threaded operation and is designed to handle very large LiDAR datasets.

LASzip is distributed as open-source software and is commonly used in conjunction with the LAStools suite. It has been integrated into other LiDAR processing ecosystems, such as PDAL, making LAZ widely readable across many workflows. The availability of LASzip has contributed to broader data sharing and archiving of LiDAR surveys due to its substantial size reductions without data loss.