Module 3 - Intro to Electromagnetic Radiation (EMR) & Satellite Sensors and Digital Image Processing - Intro to ERDAS Imagine and Digital Data Lab

 This module's lab assignment was quite different from previous coursework up to this point, as it brought the challenge of learning and working with a new program: ERDAS Imagine. ERDAS Imagine is software designed to best manipulate and extract data from raster imagery. This assignment was performed in two parts, A & B, and taught many skills involving how to effectively use this software.

Part A:

To begin this assignment, I was first to get comfortable with the basics of essential tool locations in ERDAS Imagine. Once comfortable, I was to open my first image as a 2D View. I learned the importance of which preferences to select or not select, depending on the image type, in the Raster Options tab before adding the image as a layer. I got comfortable using multiple views and how to stack them properly for ease of use. I also learned how to properly navigate an image and change its display using tools like the bands in the Multispectral tab to change the type of RGB display, depending on the images use. Once I had these basic functions under my belt, I was to prepare data for display in an ArcGIS Pro layout. I was given an image and was tasked to create a subset image from it that would carry area data relevant to the subset into a program such as ArcGIS Pro. I achieved this by first adding an area column to the attribute table of the image using the Add Area tool from the Table tab. Next, I created an Inquire Box from the Home tab and chose a subset area to extract. In the Raster tab, I selected Create Subset Image and selected the option to create From Inquire Box. To get the area of classified sections of my subset image, I repeated the steps I detailed earlier on creating an area field in the attribute table of the new layer and saved the changes. I was now able to load this subset image into ArcGIS Pro and symbolize the image based on classifications and their individual areas. 

Final layout created for Part A of the Module 3 assignment. The image above shows the subset area created (left) with a legend containing color patches and area in hectares for each classification (right). All other essential map items are present.

Part B:

This part of the lab assignment was more practice using ERDAS Imagine. I practiced examining layer information like height and width by pixel. I learned how to identify darkest and lightest pixels in a layer as well as other key statistics. I also looked at various images that highlighted the relationships of spatial, radiometric, temporal, and spectral resolution differences. Perhaps the most useful information presented was how to perform attribute calculations and selection by criteria, as these are processes I perform often in ArcGIS Pro and will undoubtedly have to perform in ERDAS Imagine in the future. I was pleasantly surprised by the similarities between Pro and Imagine.