The Open Geospatial Consortium (OGC) is excited to announce the publication of the LAZ 1.4 Community Standard, which defines a lossless compression format for LAS 1.4 point cloud data.
LAZ uses lossless compression to reduce the size of a LAS file while maintaining the general structure of the LAS format. The LAZ 1.4 format is based on LAS 1.4, as specified in the LAS Specification 1.4 — R15 by the American Society for Photogrammetry Remote Sensing (ASPRS), also an OGC Community Standard. LAZ compresses the point data block, while other LAS 1.4 structures, such as the header format, remain unchanged, although some header fields are slightly changed. The specific meaning of the uncompressed LAS point data fields is not changed.
Point data is stored in chunks, where each chunk can be decompressed independently from the other chunks. This enables random access at the granularity of the chunk size: when reading a randomly selected point, only the chunk containing that point needs to be decompressed.
LAZ 1.4 also adds support for LAS 1.4 point formats 6 to 10. For these point formats, LAZ further subdivides chunks into layers, with each layer containing a subset of fields. This allows specific fields to be accessed without decompressing all other fields.
An open source implementation of the LAZ standard is provided in the LASzip library. The relevant versions of the LASzip library are Release 3.4.3, released on November 11, 2019, and Release 3.4.4, released on April 17, 2024. These releases are identical in terms of specification.
The History of LASzip
LASzip was developed between 2007 and 2010 by rapidlasso founder and LiDAR pioneer Dr. Martin Isenburg. Martin initially developed LASzip to support his LiDAR processing software, LAStools. In 2011, he converted the implementation from an academic prototype into industry-grade production code and made LASzip open source.
In November 2011, Martin introduced LASzip to the audience at ELMF in Salzburg, Austria, through a paper and video. The innovation quickly became very popular. LASzip went on to win the 2012 Geospatial World Forum Technology Innovation Award in LiDAR Processing and was runner-up for the Most Innovative Product at INTERGEO 2012. Over the years, LASzip has become the industrial de facto standard for LiDAR compression and is supported by virtually all existing point-cloud processing tools.
Martin’s contribution extended beyond his work as a gifted software developer. He was deeply aware of technology’s impact on the world and had great respect for nature and the environment. He cared not only about technology itself, but also about its potential to improve our planet and the human condition. Martin passed away on September 7, 2021.
Learn More
As with all OGC Standards, the OGC LAZ 1.4 Community Standard is freely available to download and implement.
About OGC
The Open Geospatial Consortium (OGC) is a membership organization dedicated to using the power of geography and technology to solve problems faced by people and the planet. OGC unlocks value and opportunity for its members through Standards, Innovation, and Collaboration. Our membership represents a diverse and active global community drawn from government, industry, academia, international development agencies, research & scientific organizations, civil society, and advocates.
Visit ogc.org for more information about our work.
