Lidar Base Specification 2020 rev. A is now available

Lidar Base Specification: Table of Contents

Lidar Base Specification 2024 rev. A

Table of Contents

The major headings link to pages which contain the specifications for that section. 

Update LAS reference to R15

There are currently eleven (11) references to LAS v.1.4-R13 in the Lidar Base Specification v. 2.1. All of these will be updated to LAS v.1.4-R15. 

Require Photographs of Checkpoints

Photographs will be required for checkpoints to help identify potential sources of error in the quality control process. There are currently no requirements in the Lidar Base Specification to provide photographs of checkpoints. 

Clarify Class 0 and Withheld Flagging

The current text regarding Point Classification can be confusing with regard to points flagged as withheld. This revision clarifies the requirement.

Revise Swath Polygon Requirements

The current usage of swath polygons has moved beyond the requirements in LBS v.2.1. This revision brings the requirements into better agreement with usage.

Revise use of the LAS Withheld Bit Flag

Current wording of requirement is too broad and lacks clarity regarding which points must be flagged and how the bit flag relates to other classifications.

Vertical Accuracy Assessment Using Ground Points

This revision modifies the method for assessing absolute vertical accuracy for both NVA and VVA to require the use of ground-classified points. The requirement that unclassified point data shall meet required VVA before further classification and processing has been removed. 

Swath Separation Images

This is a new requirement for delivery of Swath Separation Images. Swath separation images use color-coding to illustrate differences in elevation (z-) values where swaths overlap. They are ancillary metadata used as visual aids to more easily identify regions within point cloud datasets that may have suspect interswath alignment or other geometric issues.