<commit_before>---
layout: post
title:  "What is a CHM, DSM and DTM? About Gridded, Raster LiDAR Data"
date:   2014-07-11 20:49:52
category: remote-sensing
categories: [remote-sensing]
tags : [lidar]
description: "Understand two common LiDAR data product formats: raster and vector and learn the basics of how a LiDAR data are processed."
image:
  feature: lidar_GrandMesa.jpg
  credit: LiDAR data collected over Grand Mesa, Colorado - National Ecological Observatory Network (NEON)
  creditlink: http://www.neoninc.org
---

<section id="table-of-contents" class="toc">
  <header>
    <h3 >Contents</h3>
  </header>
<div id="drawer" markdown="1">
*  Auto generated table of contents
{:toc}
</div>
</section><!-- /#table-of-contents -->


### Three Common LiDAR Data Products ###
- [Digital Terrain Model](http://neoninc.org/NEONedu/ESA2014/DTM.html) - This product represents the ground.
- [Digital Surface Model](http://neoninc.org/NEONedu/ESA2014/DSM.html) - This represents the top of the surface (so imagine draping a sheet over the canopy of a forest).
- [Canopy Height Model](http://neoninc.org/NEONedu/ESA2014/CHM.html) - This represents the elevation of the Earth's surface - and it sometimes also called a DEM or digital elevation model.


## LiDAR Point Clouds -- The Basics  ##
Each point in a LiDAR dataset has a X, Y, Z value and other attributes. The points may be located anywhere in space are not aligned within any particular grid. <image: LiDAR data point spacing>.
<commit_msg>rs fixed<commit_after>---
layout: post
title:  "What is a CHM, DSM and DTM? About Gridded, Raster LiDAR Data"
date:   2014-07-11 20:49:52
category: remote-sensing
categories: [Remote Sensing]
tags : [lidar]
description: "Understand two common LiDAR data product formats: raster and vector and learn the basics of how a LiDAR data are processed."
image:
  feature: lidar_GrandMesa.jpg
  credit: LiDAR data collected over Grand Mesa, Colorado - National Ecological Observatory Network (NEON)
  creditlink: http://www.neoninc.org
---

<section id="table-of-contents" class="toc">
  <header>
    <h3 >Contents</h3>
  </header>
<div id="drawer" markdown="1">
*  Auto generated table of contents
{:toc}
</div>
</section><!-- /#table-of-contents -->


### Three Common LiDAR Data Products ###
- [Digital Terrain Model](http://neoninc.org/NEONedu/ESA2014/DTM.html) - This product represents the ground.
- [Digital Surface Model](http://neoninc.org/NEONedu/ESA2014/DSM.html) - This represents the top of the surface (so imagine draping a sheet over the canopy of a forest).
- [Canopy Height Model](http://neoninc.org/NEONedu/ESA2014/CHM.html) - This represents the elevation of the Earth's surface - and it sometimes also called a DEM or digital elevation model.


## LiDAR Point Clouds -- The Basics  ##
Each point in a LiDAR dataset has a X, Y, Z value and other attributes. The points may be located anywhere in space are not aligned within any particular grid. <image: LiDAR data point spacing>.

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