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State of Indiana Orthophotography and LiDAR Program. R.N. Wilkinson Special thanks to: Jim Sparks Jim Stout Phil Worrall. Indiana’s Statewide GIS Framework Data Layers At the edge of some great accomplishments. Statewide GIS Initiatives. IndianaMap Data Sharing Initiative
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State of Indiana Orthophotography and LiDAR Program R.N. Wilkinson Special thanks to: Jim Sparks Jim Stout Phil Worrall
Indiana’s Statewide GIS Framework Data LayersAt the edge ofsome great accomplishments
Statewide GIS Initiatives • IndianaMap Data Sharing Initiative • Broadband Mapping Program • Local-Resolution NHD Development • Orthophotography & LiDAR Program • IGIC/ISPLS Height Modernization Pilot & the INDOT CORS Network • The New IndianaMap Viewer R3
Program History • 2005 Statewide Imagery Project • DHS Grant was stimulus • Program the result of the IGIC Orthophoto Workgroup • Primary goal was a one-year statewide acquisition • $8.5 Million cost • Completed in 2006
2005 Ortho Project Benefits $1.7 Billion worth of project and operationssupport
Deliverables - • Orthophotography • ECW files • Compressed files • GeoTiff • Located geographically • Metadata • Tile Index • 5000 x 5000 index • LiDAR • Digital Elevation Models • DEMs • LAS files • Hydro Line Work • Used to hydro flatten water bodies • Tile Index • 5000 x 5000 index
2011 Indiana Statewide Program • Administered through Indiana Office of Technology – State Geographic Information Officer – Jim Sparks • Base Products • 1’ Pixel Resolution – 4-Band Imagery • USGS-compliant, 1.5 meter post spacing LiDAR • Digital Elevation Model • Available Buy-up Options • 6”-inch Resolution Ortho • 3”-inch Resolution Ortho • 1-meter post spacing LiDAR
What is an Orthophotograph? Definition: A digital (electronic) aerial photograph that has been modified to remove distortion from the camera & airplane and adjusted to fit the ground surface. It is a photo that can be used as a MAP.
Cameras Distort Images All imagery hasspatial error dueto the distortingnature ofphotography. & Don’t forgetTerrain Distortion
2002 Orthos with old DEM 2003 Orthos with new DEM
Orthophoto Uses Orthophotography has the geometric characteristics of a map and the image qualities of a photograph. • distance measurements • area calculations • determination of feature shape • direction calculations • determination of coordinates at a location • analyze change
Orthoimagery • Deliverables • 4-Band 1”=200’ scale seamless orthoimagery • GeoTIFF format • Enhanced Compression Wavelet (ECW) format • 5,000 X 5,000 tiles • +/- 5.0 horizontal accuracy • NSSDA Standards • FGDC Metadata
Indiana LiDAR Program • Capture 1/3 of state/year • Base LiDAR product is: • LiDAR Point Cloud1.5 Meter Post Spacing1st & Last & Intensity(LAS v12 format) • Digital Elevation Model5-foot pixel, 5k-foot tiles,hydro-flattened(ERDAS Imagine IMG format) • Buy-up: • 1-meter LiDAR • Contours
Statewide LiDAR Data Sources • Blue counties (new 2011 -2013 LiDAR capture planned) • Other Counties (recent County LiDAR projects) • Other Areas (recent FEMA LiDAR projects ) • All data homogenized into statewide data product / delivery standard
Indiana LiDAR Program Objective • New LiDAR data – with many benefits beyond standard DEM and DTM production, especially when combined with 4-band imagery: • Automatic Feature Extraction • Change Detection • Impervious Surface Analysis • Land Use/Land Cover Extraction • Forestry Analysis • Flood Analysis • Line of Site Analysis
LiDAR • Light Detection and Ranging – laser range finding from an airplane or helicopter. • Builds a “cloud” of X,Y,Z points reflected back to the receiver. • Captures all reflective surfaces (ground, buildings, trees, utility lines). Not water. • Reflectivity can be used to determine type of surface.
LiDAR shaded blue to red, oblique view. Arrow shows perspective of next slide.
LiDAR of tree stand, oblique view. Note Cyan dots represent points on the ground. So, about 1/1000 points get to the ground through dense forest.
Definition – Digital Elevation Model • A 3D computerized representation of the variation of relief of the earth’s surface in the form of points of elevation (often supplemented by breaklines depicting severe changes in slope). • Used for:- Rectifying aerial photography.- Calculating ground contours.- 3D modeling of slope and drainage.
DTM DEM
Uses for LiDAR Data and DEM’s • Point elevations • Warp correction on imagery • Building outline detection • Forestry production determination • 3d Modeling • 3d Mapping • Change detection on built up areas
LiDAR shaded red to blue elevations. Trees are easily identifiable.
Depth Grids • Depth of flooding derived from subtracting WSEL and terrain grids • To be a standard deliverable for FEMA Flood Insurance Study modeling under RiskMAP • Also a standard input for HAZUS-MH to determine flood loss impacts
Access to Data • IU Indiana Spatial Data Portal • Single file download • Multi-file download tool • Indiana Map • State of Indiana • County Governments • Open Topography website • IGIC Corporate or Institutional Members • Hard drives available through Phil Worrall
Indiana Map A WORK IN PROGRESS Internet dependant
Indiana Map http://maps.indiana.edu/layers.html Through the Layer Gallery
Access • State of Indiana – GIO office • County Govt – • Check with local government for availability • Each County got their data delivered on hard drives.
IndianaStatewide LiDARData Introducing the Open Topography Server for Indiana
Open Topography ServerClasses of data types available • LiDAR point cloud data • Standard digital elevation models (DEMs) • For LiDAR point cloud data, web-based tools are also available to process these data into custom DEMs.