The increasing use of laser scanning technology has identified a need to establish professional practices and guidelines covering the proper planning, implementation, data processing and QA/QC of laser/lidar data in various mapping projects. Further adoption of ALS (Airborne Laser Scanning) and TLS (Terrestrial Laser Scanning) technologies by data users and mapping practitioners requires common data exchange formats, sensor calibration routines, uniform data analysis, and accuracy assessments. The ASPRS decided to form our group of interest. Its first meeting was held on November 3, 1999. The ASPRS LC has several initiatives underway in conjunction with sensor manufacturers, data providers and data users to address these issues.
Committee Review Materials
At our annual meeting in Portland 2008, several committee members volunteered their time to generate best practice documents for review (see April 29th 2008 committee meeting minutes). So far, documents relating to accuracy assessment frameworks, lidar point spacing definitions, and lidar sensor calibration have been submitted. These documents are attached here for review and comment by committee members:
- Quality Assurance and Quality Control of LiDAR Systems and Derived Data. Prepared by Ayman Habib & Jim Van Rens (Adobe PDF 468Kb)
- A New Framework for Accuracy Assessment of Lidar Data and Derived Elevation Models. Karen Schuckman, Penn State University and Lewis Graham, GeoCue Corporation (Adobe PDF 2.1Mb)
- Unbiased LiDAR Data Measurement (Draft), Ty Naus, Fugro Horizons, Inc. (Adobe PDF 680Kb)
Feel free to download and review these materials, and send your feedback either to the authors directly or to the current Airborne Lidar Committee Chair.
ASPRS Board Approves LAS 1.3 Specification (08/05/2009)
The American Society for Photogrammetry and Remote Sensing (ASPRS) is pleased to announce LAS 1.3, a new release of the open file format for lidar data storage and delivery. ASPRS has been maintaining and updating this widely used specification since its inception at the beginning of this decade.
The 1.3 release adds support for waveform encoding of laser returns. The encoding of this new data extension is optional, allowing LAS 1.3 to be used as the specification in normal multi-return delivery products.
“ASPRS has been very proactive in accommodating the rapid advances in LIDAR hardware technology with frequent updates to the LAS specification,” said Jim Plasker, Executive Director of the ASPRS. “This latest update allows lidar system vendors to store waveform information directly in the LAS file. This new capability offers exciting opportunities for developing advanced algorithms for application areas such as urban modeling and forestry. Over 50 hardware vendors, software developers, production companies and commercial/government agencies participated in the development of this latest version of the specification and thus we expect that it will be rapidly adopted for both exploitation and data delivery.”
The LAS version 1.3 specification was approved by the ASPRS Board of Directors on July 14, 2009 and is available for immediate use. The current version of the full specification, together with superseded or suspended versions, can be downloaded from the ASPRS Standards Committee LASer (LAS) File Format Exchange Activities page.
Committee Reference Materials