UW - Eau Claire Geography 338 Remote Sensing of the Environment

Goal and Background           Before a satellite image is analyzed, a number of preprocessing activities must be performed first to prepare the image for accurate information extraction. For Lab 6, students were introduced to the preprocessing exercise known as geometric correction. The two geometric correction processes introduced in this lab are image-to-map rectification and image-to-image rectification.  Methods           In Erdas Imagine, display the Chicago USGS 7.5 minutes Digital Raster Graphic and the 2000 Chicago satellite image from the Lab 6 folder in two separate viewers. The satellite image needs to be geometrically corrected based on the accurate DRG in a image-to-map rectification. With the satellite image activated, click on Control Points in the Multispectral tab. Select Polynomial in the Set Geometric window. Accept Image Layer (New View) as the default in the GCP Tool Reference Setup window. Next, navigate...

Goal and Background           The purpose of Lab 5 was to be introduced basic LiDAR data structure and processing, such as processing and retrieving surface models and digital terrain models (DTM) and processing and creating intensity images and other derivative products from a point cloud. The LiDAR data in this lab is in LAS format. It's important for a student to have experience in working with LiDAR data, as its role and potential is only growing in the remote sensing world.  Methods           For the first part of the lab, bring in the .las files in the Lab 5 folder into Erdas Imagine viewer. Change File Type to LAS as Point Cloud so the las. files can be retrieved from the Select Files window. A warning will pop up about the layer not having level of detail (statistics). Uncheck Always Ask and click Ok as this will be computed later. It's essential that LAS data that is being worked on have Metadata and a Tile Index. Th...