CGIA Geospatial Imaging . Image Processing . Feature Extraction . Visualization .

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CGIA Geospatial Imaging. Image Processing .
Feature Extraction . Visualization .

• Frank Obusek
• Program Manager
• frank.obusek_at_ncmail.net

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Geospatial Imaging

• Remotely sensed image data acquired from airborne
  and earth-orbiting acquisition systems are a
  source for much of the geographic information the
  GIS community uses today.  Expertise and tools to
  generate the data have previously not existed
  within North Carolina state government.  The
  Center for Geographic Information and Analysis
  has established Geospatial Imaging services that
  provides expertise to state and local government
  agencies that depend on up-to-date geographic
  information to meet their GIS needs.
• (use with animated sequence of images, filename
  intro_anima.gif)

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CGIAs Geospatial Imaging

• CGIA's Geospatial ImagingSupporting North
  Carolina State and Local Government Agencies with
  services and expertise in the application of
  remotely sensed image data.
• Image Processing Processing and manipulating
  image data into GIS-ready formats ready for
  feature extraction
• Feature Extraction Converting geospatial
  features from airborne and space-based imagery
  into usable GIS layers
• Visualization Visualizing multiple data layers
  of image and GIS data in one environment
• The NC Center for Geographic Information
  Analysis, a receipt-funded program in the
  Department of Environment and Natural Resources
  (DENR) (LINK TO DENR SITE) is the lead
  organization in state government for geographic
  information systems (GIS). Through a NASA funded
  research grant, CGIA has developed the expertise
  and operational capacity to obtain and use
  remotely sensed data and image processing
  technology to help support the operational
  requirements of state and local government
  agencies in North Carolina. 

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CGIAs Geospatial Imaging

• Remotely sensed image data provides a timely
  cost-effective resource to derive GIS data
• Defining methods to extract GIS information for
  multiple applications
• Helps support the daily operational programs of
  state and local government agencies

. I m a g e P r o c e s s i n g . F e a t u r
e E x t r a c t i o n . V i s u a l i z a t i
o n .
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CGIAs Geospatial Imaging

• Services
• Image Processing
• Feature Extraction
• Visualization

. I m a g e P r o c e s s i n g . F e a t u r
e E x t r a c t i o n . V i s u a l i z a t i
o n .
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Image Processing

• Image processing involves the processing and
  manipulation of aerial photography and satellite
  imagery into GIS-ready image formats.  To
  accurately derive geospatial information from
  image data, it is critical that imagery be
  properly registered, enhanced and prepared.

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CGIAs Geospatial Imaging

• Image Processing Services
• Format Conversion
• Geo-registration
• Orthorectification
• Image Reprojection
• Image Enhancement
• Image Mosaics Clipping
• Stereo Model Creation

. I m a g e P r o c e s s i n g .
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Feature Extraction

• Features visible in aerial photography and
  satellite imagery provides a valuable source of
  GIS data.  Users are able to take advantage of
  the increased availability of higher-resolution
  imagery to extract useful information. However,
  extracting impervious surface or land cover data
  using traditional pixel-based classifiers poses
  challenges.  Feature extraction tools that
  incorporate image texture and spatial context
  classifiers better permit the conversion of these
  features into a GIS environment.

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CGIAs Geospatial Imaging

• Feature Extraction Services
• Man-made features
• Natural features
• Landcover
• Change Detection

. F e a t u r e E x t r a c t i o n .
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Geospatial Imaging Workflow
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Visualization

• Visualization is a powerful rendering capability
  to interpret geospatial relationships
  between objects and features extracted from
  imagery.  Multiple layers of data can be viewed
  at once.  Desktop visualization can make time in
  the field more efficient. 

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CGIAs Geospatial Imaging

• Visualization Services
• Perspective views
• Fly-throughs
• Scenario Modeling
• Veiwshed Analysis
• Disaster Planning

. V i s u a l i z a t i o n .
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Technical Support

• Technical Support Services offers a resource of
  expertise to state and local government agencies
  interested in the utility and  benefit of
  remotely sensed data products. Outreach is a key
  component of CGIAs future design of
  image-derived geospatial products and the
  campaign to assist NC state and local government
  agencies in the education to use image-derived
  geospatial products.

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CGIAs Geospatial Imaging

• Technical Support Services
• Workshops
• Project Support
• Software Support
• Applications Research
• Project Development

. S u p p o r t .
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Geospatial Imaging Applications Demonstrations
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Geospatial Imaging Workflow
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Stormwater Billing Impervious surface area per
parcel
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Updating Impervious Surface Data
A.
B.
2002 Impervious
2004 Aerial Photography
C.
D.
2004 Impervious Update
2004 Impervious using 2002 Mask
Figure demonstrates the successful application of
using image masking to update existing impervious
surface data. The example shown here is of the
Mallard Creek East annex north of Charlotte, NC.
A.) Impervious surface data (yellow polygons) was
generated from 30 cm resolution true color aerial
photography. B.) New 2004 aerial photography was
flown with 15 cm resolution. Compared to the
2002 impervious surface data, the imagery clearly
shows the development of new homes. C.) Using
the existing impervious surface data from 2002 as
an image mask, the feature extraction method is
focusing on only the new developed areas visible
in the image. The orange polygon data, along
side the yellow polygon data, show the new
impervious surface to be added to the existing
impervious surface data layer. D.) Combing the
2004 impervious surface data with the 2002
results in an updated data set that can be
immediately implemented into storm water billing
structure.
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NPDES Phase II Stormwater

• Benefit from accurate impervious surface data in
  developing SW management plans
• Feature Extraction saves time and costs
• Updating impervious surface data becomes easier
  once it is collected

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Landcover Feature Extraction
Input Data
Output GIS Data
New Bern, NC Landcover Data
Using 1998 NC DOQQ color-infrared orthorectified
aerial photography
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Tree Type Delineation
Input Data
Output GIS Data
Hardwood leaf off features
Hardwood leaf off features
Pine leaf on features
Pine polygons
Using Orange County 2003 true color
orthorectified aerial photography
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Urban Green Space Delineation
Input Data
Output GIS Data
Downtown Charlotte, NC
Using Mecklenburg County 2002 true color
orthorectified aerial photography
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Mapping Development GIS Update Revisit
Input Data
Output GIS Data
Using Mecklenburg County 2002 true color
orthorectified aerial photography
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Contact Information

• Contact InformationCGIA's RSP is headquartered
  in the DENR Asheville Regional Office and
  operates under normal business hours 8 AM to 5 PM
  eastern standard time.  Direct contact can be
  made using the information below.   For
  information, please contact RSP Manager Frank
  ObusekTelephone [phone]FAX (828)
  299-7043 Postal address2090 US Highway 70,
  Asheville, NC 28778 Electronic mail
  Frank.Obusek_at_ncmail.net