Module 6 - Image Preprocessing 1: Spatial Enhancement & Radiometric Correction

In this week's module we covered two major image enhancing techniques that are commonly used as a "preprocessing" step before analysis: spatial enhancement and radiometric correction.

For our lab assignment, specifically, we learned how to download satellite imagery using U.S. Geological Survey's (USGS) Global Visualization Viewer (GloVis). Then we performed spatial enhancements to a Landsat 7 ETM+ image, which are known to have lines of no data, giving the image a "striped" effect due to a malfunction that occurred in 2003 called Scan Line Corrector failure.

We enhanced our image by applying Low Pass and High Pass Filters using the Convolution tool in ERDAS Imagine, as well as utilizing the Fourier Transformation functions. In addition, I personally attempted to use the Focal Analysis tool and the Destrip TM Data tools to no avail. Lastly, we also performed spatial enhancements using a tool in ArcMap: the Focal Statistics tool under Spatial Analyst > Neighborhood. This lab session was very interesting, but quite challenging.