Photo Interpretation and Remote Sensing - Mod 4
Using the map from last weeks lab we investigated random areas of the map to verify the classification schemes we had selected. Since we weren't able to field check the areas we used Google maps to do so.
We started by creating a point shapefile, then starting an editing session to add 30 points to the file. I chose the Stratified Random Sample Protocol to select the locations for my points.
Once I had the points selected I used the Identify tool to determine their coordinates in Degrees, Minutes and Seconds and entered that data in Google. The image in Google was much clearer than the TIFF we worked from originally. Even in those areas where I wasn't able to get a street view I was able to see the area clear enough to tell if I had gotten it right or not. I was not surprised to discover I made the most mistakes on the islands in the river. They were very difficult to distinguish in the TIFF so I guess at most of them. In Google I was better able to tell there were no trees so what I had marked as Forested Wetlands was actually Non-Forested Wetlands. The only real surprise was to find a house with a nice lawn, trees and even a few flower gardens in what had once been just a sandy area. Overall my accuracy came to 67%
No comments:
Post a Comment