By
spatially and spectrally enhancing an image, pattern recognition can be
performed with human eye. Spectral recognition can be more scientific using a
computer system The pixels are sorted based on mathematical criteria. The
classification process breaks down into two parts: training and classifying
(using a decision rule).
Step 1: Gathering/Acquiring
Digital image
Step 2: a) Selection of Training sets for
classification for specific cover types. b) Establish spectral
signature for each cover type. Step 3: Signature statistics – Mean Plots – The mean plots
shows the separation of all the landcover signature in all channels. Histograms
– It shows the distribution of the signature in multiple bands.
Step 4: Classified
Image.
Step 5: Accuracy Assessment.- Overall Accuracy 84% Ancillary Data: Aerial
Photography of Lucas County, Topozone Maps, and Teraserver. Results: The supervised
classification performed on both the Landsat 5 images is 84% accurate. The 2004
image shows sufficient urban growth in south of Lucas county and slight
decrease in forested areas.