Wednesday, April 20, 2016

Lab 4 - Miscellaneous Image Functions

Goals:

The goals for this lab were as follows:
  1. Delineate a study area from a larger satellite image scene
  2. Demonstrate how spatial resolution of images can be optimized for visual interpretation purposes
  3. Introduce some radiometric enhancement techniques in optical images
  4. Link a satellite image to Google Earth which can be a source of ancillary information
  5. Introduce students to various methods of resampling satellite images
  6. Explore image mosaicking
  7. Expose students to binary change detection with the use of graphical modeling

Methods: 

Part 1: Image subsetting of study area

Section 1: subsetting with the use of an Inquire box
  • Open the TM image eau_claire_2011.img, click on Raster
  • Right click and click on Inquire Box; this brings up the Inquire Box in the viewer
  • Put cursor inside the Inquire Box, hold down left mouse button (LMB), and position the box over the Eau Claire/Chippewa counties area
  • Click Apply in the viewer window and use the LMB to position the inquire box viewer away from the raster tools
  • Under the Raster tab, click Subset & Chip and then Create Subset Image from the drop down menu
  • Click on the folder icon under Output File and save the subset as eau_claire_2011sb_ib.img in Image_Subset folder in the Lab 4 personal folder; next click on From Inquire Box, accept remaining default values, and click OK
  • Once the model has ran, click Dismiss and then Close; close the inquire box and clear the view
For the result, see Figure 1 in the results section below

Section 2: subsetting with the use of an area of interest (AOI) shape file



Results:

Figure 1: Subset image using Inquire box

Figure 2: Subset image using an area of interest shape file

Figure 3: Mosaicked image using Mosaic Express

Figure 4: Mosaicked image using MosaicPro

Figure 5: Histogram of difference image 

Figure 6: Map showing change in brightness values using the spatial modeler 

Sources: 
  • Earth Resources Observation and Science Center
  • United States Geological Survey (USGS)
  • Mastering ArcGIS 6th Edition Dataset by Maribeth Price, McGraw Hill. 2014.