Lidar Base Specification: Table of Contents

Download a copy of the Lidar Base Specification 2024 rev. A online content

Revision History

• 2024 rev. A
• 2023 rev. A
• 2022 rev. A
• 2021 rev. A
• 2020 rev. A
• Version 2.1
• Version 2.0
• Version 1.3
• Version 1.2
• Version 1.1

Collection

• Collection Area
• Quality Level
• Multiple Discrete Returns
• Intensity Values
• Nominal Pulse Spacing
• Data Voids
• Spatial Distribution and Regularity
• Collection Conditions

Data Processing and Handling

• American Society for Photogrammetry and Remote Sensing LAS File Format
• Time of Global Positioning System Data
• Datums
• Coordinate Reference System
  • Well-Known Text
• Units of Reference
• File and Point Source Identification
• Positional Accuracy Validation
  • Absolute Horizontal Accuracy
  • Relative Vertical Accuracy
    • Intraswath Precision
    • Interswath (Overlap) Consistency
  • Check Points
  • Absolute Vertical Accuracy
• Use of the LAS Withheld Bit Flag
• Use of the LAS Overlap Bit Flag
• Point Classification
• Classification Consistency
• Tiles
• Point Duplication

Deliverables

• Metadata
• Survey Point Delivery
• Swath Separation Images
• Classified Point Data
• Bare-Earth Surface (Raster Digital Elevation Model)
• Breaklines

Digital Elevation Model Surface Treatments

• Bridges
• Hydro-Flattening

References

Tables

• Table 1: Aggregate nominal pulse spacing and density.
• Table 2: Relative vertical accuracy for light detection and ranging swath data.
• Table 3: Land cover classes.
• Table 4: Absolute vertical accuracy for light detection and ranging data and digital elevation models.
• Table 5: Minimum light detection and ranging data classification scheme.
• Table 6: Minimum digital elevation model cell size.

Figures

1. Image showing single coverage collection, no overlap.
2. Image showing designed double coverage collection, 50-percent overlap.
3. Image showing designed double coverage collection, cross-flights with 20-percent overlap.
4. Example of survey point delivery in a GeoPackage.
5. Example of a swath separation image.

Glossary

Appendix 1: Maximum Surface Height Raster 

Appendix 2: Hydro-Flattening Reference 

Appendix 3: Light Detection and Ranging Metadata Example 

Appendix 4: Light Detection and Ranging Metadata Template 

Appendix 5: Well-Known Text Coordinate Reference System Examples

Appendix 6: Supplemental Information

Appendix 7: Common Data Upgrades