Lab 5

Goal

The goal of this lab is to gain basic knowledge on Lidar data structure and processing. Some of the objectives are processing and retrieval of various surface and terrain models, and processing and creation of intensity image and other derivative products from point cloud. 

Methods

Part one of lab 5 was "Point cloud visualizatoin in Erdas Imagine". In this section we used Erdas to view a lidar point cloud file. We looked at things like the metadata and tile index. We then opened the same image in ArcMap because it gives a better interface to work with the image. 

The real fun started in Part two of the lab. The title was, "Generate a LAS dataset and explore lidar point clouds with ArcGIS. We were supposed to pretend that we were a GIS manager working on a project for the City of Eau Claire. We had acquired lidar point cloud in LAS format for a portion of the City. We first wanted to initiate an initial quality check on the data by looking at its area and coverage, and also verify the current classification of the lidar. We were given the tasks of creating a LAS dataset, explore the properties of the dataset, and visualize the LAS dataset as point cloud in 2D and 3D. 

We started off by creating a LAS folder and a dataset in the folder. We added in data that was given to us. From there, you could look at all the data and observe all of the values that came with it. We added a coordinate system to the dataset for both the XY coordinate system and the Z system. Once the dataset was finished, we brought it into ArcMap and explored the data. Looking at the elevation and point density on the map. 

In Part 3 of the lab, we worked on the "generation of lidar derivative products". This meant that we were deriving DSM and DTM products from our point cloud data. We used tools in ArcMap to create our DSM, DTM, and Hillshade images. The image below, is one of the Hillshade images

 In the last section of our lab, we derived a lidar intensity image from point cloud data. The image below is a screenshot of my lidar intensity image taken from Erdas Imagine.






















Sources

All data used was given to us and explored in ArcMap and Erdas Imagine.