GIS 5027 - Spatial Enhancement, Multispectral Data, and Band Indices

 As the title of this week's blog suggests, week 4 of Remote Sensing and Photo Interpretation was focused on various types of spatial enhancement, multispectral data and band indices. Spatial enhancement is a key preprocessing step that usually takes place before using or conducting detailed analysis of imagery. Some of the spatial enhancement processes explored include low pass filter, high pass filter and focal statistics. In addition to spatial enhancement, geospatial professionals also usually view the properties of the multispectral data to help understand what the imagery is depicting. To garner more information about the imagery we explored the histogram and manipulated it to bring attention to features that may have otherwise not been seen, and we learned about the inquire cursor that displays information on individual pixels in an image. Lastly, we learned how to create a Normalized Differential Vegetation Index (NDVI) and the various band combinations used to highlight certain features. 

The lab assignment then put students knowledge to the test by requiring us to identify features using the skills learned. Below are three maps, each highlighting a specific feature. 

Map depicting a river feature in the area of the Olympic Mountains, Washington State,  using band combination False Natural Color.

Map depicting snow caps in the Olympic Mountains, Washington State, using band combination True Color. 

Map depicting water feature in the area of the Olympic Mountains, Washington State, using band combination False Color IR. 







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