# 1 Introduction

lidR is an R package for manipulating and visualizating airborne laser scanning (ALS) data with an emphasis on forestry applications. The package is entirely open source and is integrated within the geospatial R ecosytem (i.e. raster, sp, sf, rgdal etc.). This guide has been written to help both the ALS novice, as well as seasoned point cloud processing veterans. Key functionality of lidR includes functions to:

• Read and write .las and .laz files and render customized point-cloud display (section 2)
• Process point clouds including point classification (section 3), digital terrain models (section 4), normalization (section 5) and digital surface models (section 6)
• Perform individual tree segmentation (section 7)
• Compute standard and user-defined metrics at different levels of regularisation (sections 8, 9, 10, 11, 12 and 13)
• Manage processing for sets of point-cloud files - referred to as a LAScatalog (sections 14 and 15)
• Guidelines for implementing area-based approaches to forest modelling using ALS data (section 16)
• Facilitate user-defined processing streams for research and development (section 17)
• Discover the plugin system (section 18)

The current release version of lidR can be found on CRAN and the source code is hosted on GitHub.

Development of the lidR package between 2015 and 2018 was made possible thanks to the financial support of the AWARE project NSERC CRDPJ 462973-14; grantee Prof. Nicholas C. Coops.

Development of the lidR package between 2018 and 2020 was made possible thanks to the financial support of the Ministère des Forêts, de la Faune et des Parcs of Québec.

The book is shared under CC-BY-NC-SA 2.0

This book was created to provide hands on descriptions and tutorials for using lidR and is not the formal package documentation. The comprehensive package documentation is shipped with the package.