This is a test of Andrew Klein's New Document Formt

More documents

Recommendations

Info

Task 2. The thermal image band that we have is low gain representation. Given a subset of Landsat ETM+ band 6 image sub_etm6, you are required to perform the following quantitative analysis: Question 6. Determine the L MAX, L MIN, Q CALMAX, Q CALMIN values for the low gain representation of ETM+ band6, and construct the correct formula for converting the DN values in band 6 to the absolute radiance. Question 7. Now apply (using band math) this formula to the entire image to calculate the absolute radiance for each pixel, and determine the range of radiance values for this sub image using the compute statistics function. Question 8. Determine average radiance values for typical pixels of water, grass, forest, buildings and roads. Question 9. Write out the formula to convert the absolute radiance to temperature. Using band math apply this formula to each pixel in the image to calculate the effective at-satellite temperatures, and find out the temperature range for this sub image and also determine the temperatures for the typical pixels of water, grass, forest, buildings and roads you analyzed in Question 8. Question 10. Smooth the temperature image using a low-pass filter and display the temperature image using the pseudo-color mode and select an appropriate color table to display surface temperature. Make a hardcopy map to show the spatial distribution of the temperature. - 6 -
Tips Much of what is required here you have done before so you should try to remember how to do this again. 1. To convert the DN values to at-satellite radiance, you first need to construct a formula of the type listed in equation (1). You can then apply this formula using either band math or the gain/offset preprocessing function. [To do a log use the alog function and be sure to use your parentheses correctly]. 2. You can use ROI tool to determine both the at-satellite radiance and at-satellite temperatures for the different surface features. 3. You can use Basic Tools Statistics Compute Statistics to compute the statistics for an image. 4. To do pseudocolor mapping of temperature on the Image menu select Tools Color Mapping ENVI Color Tables to set a pseudo-color for displaying a temperature image. Select an appropriate color table that makes sense to correctly display temperatures. 5. To smooth the temperature image suing a low-pass filter, which can be found in Filter Convolutions and morphology on the ENVI main menu bar. You should select the Convolutions and Morphology Tool window, and use a Low Pass with a 3×3 Kernel Size. Click Quick Apply; select the appropriate input band Notice that the temperature image is smoothed. Make a hard copy of this image and include it in your lab report. - 7 -
Page 1 and 2: -1- Lab Exercise GEOG 361/651 Dr. A
Page 3 and 4: The L MINs and L MAXs are the spect
Page 5: III. Instructions Task 1: The therm
Page 9: Task 4. Under the ATLAS subdirector

This is a test of Andrew Klein's New Document Formt

Create successful ePaper yourself

Delete template?

Save as template?