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. 







Comments

Post a Comment

Popular posts from this blog

GIS 5935 - Data Quality Assessment

Image
Like the second assignment, this module continues to focus on data quality. More specifically, this week focused on data quality of road networks. As such, we were tasked with performing a comparative assessment to determine the completeness of a street centerline shapefile and a Topologically Integrated Geographic Encoding and Referencing (TIGER) road shapefile for Jackson County, Oregon.  To perform this assessment we utilized a non standard method, based on that used by M. Haklay in the "Comparative Study of OpenStreetMap and Ordinance Survey datasets" in 2010. This included using a grid, which encompasses the study area, to clip the road network into smaller sections. These smaller sections give more detailed insight into areas which may be considered complete or incomplete. Once the roads were clipped to each grid cell/section the lengths were calculated and then compared.  My analysis determined that 134 of the grid cells/sections contained parts of the street centerlin
Read more

GIS 5935 - Surfaces - TINs and DEMs

Image
Having moved on from the modules regarding data quality, this week we were introduced to surfaces and surface models, more specifically Triangulated Irregular Networks (TINs) and Demographic Elevation Models (DEMs). TINs are based on vector data and are made up of a series of linked triangles that vary in shape and size, but display a 3D representation of a surface. DEMs are based on raster data, more specifically the spot heights associated with each grid part of a raster.  For this lab we were tasked with creating a TIN and DEM, as well as displaying contours based on both of them. We were then tasked with comparing the contours produced by both. Below I have included images of my results.  (a) Contour lines based on the TIN (b) Contour lines based on the DEM The contours produced as a result of the TIN appear to be more jagged, while the contours produced from the DEM have a smoother appearance. There is also a noticeable difference between the derived contours in areas that hav
Read more

GIS 5100 - Who is Gabrielle Hudson?

Image
Hi! My name is Gabrielle. I am currently a part time student in the MSc. Geographic Information Science Administration program at the University of West Florida (UWF), but I'm also a full time employee at the Bahamas National Geographic Information Systems (BNGIS) Centre, in The Bahamas. My official position is GIS Analyst and GI Education Coordinator, however due to the small staff compliment we all wear many hats. Some of my responsibilities include maritime delimitation, disaster preparedness and response, training, mentoring, data collection and data management. While I enjoy most aspects of GIS, my favorite part is producing a meaningful and esthetically pleasing map. I decided to pursue a masters level degree with the hope of increasing my knowledge in GIS, which will better prepare me for future opportunities at my current place of employment, or where ever the opportunity may present itself. The degree option at UWF seemed to perfectly match my goal of future advancement as
Read more