City of Wahpeton, ND Digital Orthophotography and Topographic Mapping
Metadata also available as
Metadata:
- Identification_Information:
-
- Citation:
-
- Citation_Information:
-
- Originator: City of Wahpeton, ND
- Publication_Date: 20121130
- Title:
-
City of Wahpeton, ND Digital Orthophotography and Topographic Mapping
- Publication_Information:
-
- Publication_Place: Wahpeton, ND
- Publisher: City of Wahpeton, ND
- Description:
-
- Abstract:
-
This image and LiDAR data is the result of private and government
entities working together under the guidance of the City of
Wahpeton, ND. Fugro Earthdata, Inc. acquired Digital Imagery
with sensor ADS80 SH82 for areas of Wahpeton, ND
project area April 11, 2012. The project encompassed an
area of approximately 24 square miles. A Leica ADS80/SH82
Digital Camera system including an inertial measuring unit
(IMU) and a dual frequency airborne GPS receiver was used
for the digital image acquisition. Imagery acquisition was
performed April 11, 2012 at 2400' AMT (above mean terrain),
with 30 percent sidelap between the flight lines. Ground
control survey was provided by the City of Wahpeton. Digital
orthophotos in TIFF format were produced with a resolution
of 0.25 foot utilizing the ADS80/SH82 imagery and the
Red River mapping Initiative LiDAR DEM. Delivery was on an
External Hard Drive. Fugro Earthdata, Inc. acquired LiDAR
data with Fugro's proprietary LiDAR sensor for of Wahpeton,
ND project area March 30,2012. The project encompassed an
area of approximately 7.6 square miles. A FLIMAP LiDAR system
including an inertial measuring unit (IMU) and a dual
frequency airborne GPS receiver was used for the LiDAR acquisition.
Acquisition was performed March 30, 2012 at 2100' AMT (above mean
terrain), with 20 percent sidelap between the flight lines.
Ground control survey was provided by the City of Wahpeton.
Delivery was on an External Hard Drive.
- Purpose: The orthophotos will be used for GIS and planning.
- Time_Period_of_Content:
-
- Time_Period_Information:
-
- Range_of_Dates/Times:
-
- Beginning_Date: 20120330
- Ending_Date: 20121130
- Currentness_Reference: Acquisition Date
- Status:
-
- Progress: Complete
- Maintenance_and_Update_Frequency: None planned
- Spatial_Domain:
-
- Bounding_Coordinates:
-
- West_Bounding_Coordinate: -096.679236
- East_Bounding_Coordinate: -096.574127
- North_Bounding_Coordinate: +46.355299
- South_Bounding_Coordinate: +46.209747
- Keywords:
-
- Theme:
-
- Theme_Keyword_Thesaurus: None
- Theme_Keyword: Aerial Photography
- Theme_Keyword: Orthophoto
- Theme_Keyword: LiDAR
- Place:
-
- Place_Keyword_Thesaurus: Geographic Names Information System
- Place_Keyword: ND
- Place_Keyword: Wahpeton
- Access_Constraints: There are no limitations for access.
- Use_Constraints: unknown
- Point_of_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: City of Wahpeton
- Contact_Person: Randy Nelson
- Contact_Position: Public Works Director
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 1900 Fourth Street North
- City: Wahpeton
- State_or_Province: ND
- Postal_Code: 58075
- Country: United States
- Contact_Voice_Telephone: 701-642-6565
- Contact_Electronic_Mail_Address: RandyN@wahpeton.com
- Hours_of_Service: 8am-5pm, Central Time
- Data_Quality_Information:
-
- Attribute_Accuracy:
-
- Attribute_Accuracy_Report:
-
GPS phase data was post processed with continuous
kinematic survey techniques using "On the Fly" (OTF)
integer ambiguity resolution. The GPS data was processed
with forward and reverse processing algorithms. The
results from each process, using the data collected at the
airport, were combined to yield a single fixed integer phase
differential solution of the aircraft trajectory. The
differences between the forward to reverse solution within
the project area were within project specifications (<10cm)
in both the horizontal and vertical components, indicating a
valid and accurate solution. An IMU was used to record
precise changes in position and orientation of the ADS80
Digital Camera System. All IMU data was processed post
flight with a filter to integrate inertial measurements and
precise phase differential GPS positions. The resulting
solution contains geodetic position, omega, phi, kappa,
and time for digital image processing.
- Logical_Consistency_Report: Tiling is based on quarter section sheets.
- Completeness_Report: Complete
- Positional_Accuracy:
-
- Horizontal_Positional_Accuracy:
-
- Horizontal_Positional_Accuracy_Report:
-
The orthophotography meets National Map Accuracy Standards
of 1947 for map scale at 1" = 50'
- Lineage:
-
- Source_Information:
-
- Source_Citation:
-
- Citation_Information:
-
- Originator: Fugro Earthdata, Inc.
- Publication_Date: 20121130
- Title:
-
City of Wahpeton, ND Digital Orthophotography and Topographic Mapping
- Source_Scale_Denominator: 6000
- Type_of_Source_Media: Digital Data
- Source_Time_Period_of_Content:
-
- Time_Period_Information:
-
- Range_of_Dates/Times:
-
- Beginning_Date: 20120330
- Ending_Date: 20120411
- Source_Currentness_Reference: Date of Photography
- Source_Citation_Abbreviation: Ortho Imagery and LiDAR
- Source_Contribution: ADS80 SH82 and FLIMAP
- Process_Step:
-
- Process_Description:
-
The Leica GeoSystems XPro software was used for
downloading and preparing imagery collected with the
ADS80 Airborne Digital Sensor for softcopy
photogrammetric use. The raw image was download in the
field with XPro to a portable workstation. This enabled a
quick look at image quality and coverage. Using the
Leica Geosystems IPAS software package the GPS data was
differentially processed against a base station. After the
differential GPS solution was checked and verified the
Leica Geosystems IPAS program was used to compute an
integrated GPS/IMU navigation solution at one-second
intervals. Using the GPS/IMU trajectory computed by the
Leica Geosystems IPAS software and the camera calibration,
XPro computed a full x,y,z, omega,phi,kappa exterior
orientation of each scan line. Using the orientation data
file produced the L0 imagery was resampled. The
resampling removes most aircraft motion and provides
epipolar geometry imagery for stereo viewing, automated
aerotriangulation and automated DEM extraction. The
Level 1 epipolar-resampled and georeferenced imagery
usually will provide a pixel’s true ground location to within a
few pixels without any additional processing. To improve
accuracy, a fully automatic aerotriangulation process was
performed to minimize the residual errors in the GPS/IMU
derived exterior orientations. The aerotriangulation also
allowed the introduction of ground control and checkpoints
to ensure the accuracy specifications were achieved.
Automated aerotriangulation of ADS80 imagery was
performed with the Socet Set Automatic Point
Measurement (APM) tool. A digital elevation model (DEM)
was required for orthophoto production. Iowa Statewide
LiDAR Data was used as the DEM for orthophoto creation.
Orthophotos were created utilizing Leica Geosystem XPro
software. Orthos were created in UTM Zone 15
meters. The orthos were mosaiced together using
proprietary image database and mosaicing software.
The database was edited for seamlines, and other artifacts.
Since the imagery was calibrated by the system calibration
no color correcting was done to the imagery. The imagery was
clipped out of the database into the sheet layout generated
based on client use requirements. In the clipping stage,
the coordinate system and georeferencing was embedded
into the header of the TIFF file. The imagery tiles were
QC'ed and delivered on an External Hard Drive.
- Process_Date: 20120930
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: Fugro Earthdata Inc.
- Contact_Person: Michael Larson
- Contact_Position: Project Manager
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 3600 Jet Drive
- City: Rapid City
- State_or_Province: South Dakota
- Postal_Code: 57703
- Country: United States
- Contact_Voice_Telephone: 605-343-0280
- Contact_Facsimile_Telephone: 605-343-0305
- Contact_Electronic_Mail_Address: mlarson@fugro.com
- Hours_of_Service: 8am-5pm Mountain Time
- Process_Step:
-
- Process_Description:
-
Fugro EarthData utilized a XPro workflow for processing the
Aerotriangulation for the imagery covering Wahpeton. The
airborne GPS data was processed and integrated with the
inertial measurement unit (IMU). The resulting imagery and
control were imported into the XPro system for use in the
aerotriangulation. The ADS40 SH52 imagery was
downloaded onto the server and brought over to the XPro
system. The ground control was used in conjunction with
the processed airborne global positioning system (ABGPS)
results for the aerotriangulation. The ground control points
were read in all available imagery and tie points between
flight lines were selected. A fully analytical bundle
adjustment was run. The properly formatted GPro results
were used for subsequent processing.
- Source_Used_Citation_Abbreviation: Aerotriangulation
- Process_Date: 20120930
- Source_Produced_Citation_Abbreviation: AT
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: Fugro EarthData, Inc.
- Contact_Person: Michael Larson
- Contact_Position: Project Manager
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 3600 Jet Drive
- City: Rapid City
- State_or_Province: SD
- Postal_Code: 57703
- Country: USA
- Contact_Voice_Telephone: 605-343-0280
- Contact_Facsimile_Telephone: 605-343-0305
- Contact_Electronic_Mail_Address: mlarson@fugro.com
- Hours_of_Service: Mon - Fri 8:00am to 5:00pm Mountain Time
- Process_Step:
-
- Process_Description:
-
KLT Atlas was used in the planimetric feature collection
from the ADS40 SH52 imagery acquired over the Wahpeton
project area. The imagery along with airborne GPS and
IMU data was exported out of XPro in a format usable by
KLT Atlas software. The imagery and exterior orientation
parameters were brought into KLT Atlas software for 3D
collection of the planimetric features. The softcopy
technicians used the RGB forward bands and the RGB
nadir bands for the stereo viewing of and collection from the
imagery. The areas of collection were tiled out into more
manageable sizes to accommodate the software and
workstation capabilities. The softcopy technician then
collected the planimetric features identified on the
planimetric list. After the technicians completed collection
of the planimetric features, a QC was completed to ensure
the thoroughness of the collection This review began by
ensuring coverage and then that all features were
collected and reside on the appropriate layers in support of
the graphics editing process. After the planimetric QC was
completed, the graphics edit technicians generated the
polygons and polylines that were used to generate the
ArcGIS Personal Geodatabase. The ArcGIS File
Geodatabase is in ArcGIS Version 9.3.
- Source_Used_Citation_Abbreviation: Planimetric Feature Collection
- Process_Date: 20121130
- Source_Produced_Citation_Abbreviation: Planimetric Features
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: Fugro EarthData, Inc.
- Contact_Person: Michael Larson
- Contact_Position: Project Manager
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 3600 Jet Drive
- City: Rapid City
- State_or_Province: SD
- Postal_Code: 57703
- Country: USA
- Contact_Voice_Telephone: 605-343-0280
- Contact_Facsimile_Telephone: 605-343-0305
- Contact_Electronic_Mail_Address: mlarson@fugro.com
- Hours_of_Service: Mon - Fri 8:00am to 5:00pm Mountain Time
- Process_Step:
-
- Process_Description:
-
LiDAR timed reflection data and the IMU SBET flies were
processed together using LiDAR processing software.
The data set for each flight line was checked for project
area coverage, data gaps between overlapping flightlines,
and tension/compression areas (areas where data points
are more or less dense that the average project specified
post spacing). Using an iterative process that involves
analyzing raster difference calculations the
omega,phi,kappa angle corrections for the LiDAR
instrument were determined. Corrections were applied to
the LiDAR data set. Extensive comparisons were made of
vertical and horizontal positional differences between
points common to two or more LiDAR flight lines. An
intensity raster for each flight line was generated and
verified that intensity was recorded for each LiDAR point.
LiDAR ground points were compared to independently
surveyed and positioned ground control points at both the
airport bore-sight area and the project area. Based on the
results of these comparisons, the LiDAR data was
vertically biased to the ground.
1) PRE-PROCESSING STAGE
LiDAR, GPS and IMU data are processed together using
LiDAR processing software. The LiDAR data set for each
flight line is checked for project area coverage and LiDAR
post spacing is checked to ensure it meets project
specifications. The LiDAR collected at the calibration area
is used to correct the rotational, atmospheric, and vertical
elevation differences that are inherent to LiDAR data.
Intensity rasters are generated to verify that intensity was
recorded for each LiDAR point. LiDAR data is transformed
to the specified project coordinate system. By utilizing the
ground survey data collected at the calibration site and
project area, the LiDAR data is vertically biased to the
ground. Comparisons between the biased LiDAR data and
ground survey data within the project area are evaluated
and a final RMSE value is generated to ensure the data
meets project specifications. The data set is trimmed to
the digital project boundary including an additional buffer
zone which is typically about 50 meters (buffer zone
assures adequate contour generation from the DEM). The
resulting data set is referred to as the raw LiDAR data.
2) SURFACING STAGE
The raw LIDAR data is processed through a minimum
block mean algorithm and points are classified as either
bare earth or non-bare earth. User developed "macros"
that factor mean terrain angle and height from the ground
are used to determine bare earth point classification. The
next phase of the surfacing process is a 2D edit procedure
that ensures the accuracy of the automated feature
classification. Editors use a combination of LiDAR
reflection and tin-editing software to assess points. The
LiDAR data is filtered, as necessary, using a quadric error
metric to remove redundant points. This method leaves
points where there is a change in the slope of surfaces
(road ditches) and eliminates points from evenly sloped
terrain (flat field) where the points do not affect the surface.
The resulting data set is referred to as "bare-earth LiDAR"
3) BREAKLINE COLLECTION
Breaklines will be collected on hyrdo features in order to
properly define the topography. Breaklines were collected
utilizing the stereo imgery collected for ortho production.
4) CREATION OF THE DEM
The bare-earth LiDAR surface will be triangulated to form
an evenly spaced DEM.
-No data voids due to system malfunctions or lack of
overlap
-Dense vegetation data voids minimized by automatic
removal process
-instrument calibrated for every mission
-flight plans are parallel flight lines with at least one cross
flight line to assure positional accuracy.
-Flight plan considers requirements for point density, terrain,
PDOP, and KP index
-All data and products associated with contract
deliverables will meet or exceed relevant NMAS
standards and full comply with FGDC metadata format
standard
-Standard coordinates, projections and datums available.
- Process_Date: 20121130
- Process_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: Fugro EarthData, Inc
- Contact_Person: Michael Larson
- Contact_Position: Project Manager
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 3600 Jet Drive
- City: Rapid City
- State_or_Province: SD
- Postal_Code: 57703
- Country: USA
- Contact_Voice_Telephone: 605-343-0280
- Contact_Facsimile_Telephone: 605-343-0305
- Contact_Electronic_Mail_Address: mlarson@fugro.com
- Spatial_Data_Organization_Information:
-
- Direct_Spatial_Reference_Method: Raster
- Raster_Object_Information:
-
- Raster_Object_Type: Pixel
- Row_Count: 11600
- Column_Count: 11600
- Vertical_Count: 3
- Spatial_Reference_Information:
-
- Horizontal_Coordinate_System_Definition:
-
- Planar:
-
- Grid_Coordinate_System:
-
- Grid_Coordinate_System_Name: State Plane Coordinate System 1983
- State_Plane_Coordinate_System:
-
- SPCS_Zone_Identifier: North Dakota State Plane South Zone 3302
- Lambert_Conformal_Conic:
-
- Standard_Parallel: 46.183333
- Standard_Parallel: 47.483333
- Longitude_of_Central_Meridian: -100.500000
- Latitude_of_Projection_Origin: +45.666666
- False_Easting: 1968500.0
- False_Northing: 0
- Planar_Coordinate_Information:
-
- Planar_Coordinate_Encoding_Method: row and column
- Coordinate_Representation:
-
- Abscissa_Resolution: 0.25
- Ordinate_Resolution: 0.25
- Planar_Distance_Units: Survey Feet
- Geodetic_Model:
-
- Horizontal_Datum_Name: North American Datum of 1983
- Ellipsoid_Name: Geodetic Reference System 80
- Semi-major_Axis: 6378434.181
- Denominator_of_Flattening_Ratio: 298.257222101
- Vertical_Coordinate_System_Definition:
-
- Altitude_System_Definition:
-
- Altitude_Datum_Name: North American Vertical Datum of 1988
- Altitude_Resolution: 0.001
- Altitude_Distance_Units: Feet
- Altitude_Encoding_Method:
-
Explicit elevation coordinate included with horizontal coordinates
- Entity_and_Attribute_Information:
-
- Overview_Description:
-
- Entity_and_Attribute_Overview:
-
0.25 foot pixel resolution Orthophotography and 1 foot contour interval LiDAR
- Entity_and_Attribute_Detail_Citation:
-
Project was also delivered in MN DOT Watkins County Coordinate System
- Distribution_Information:
-
- Distributor:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: City of Wahpeton
- Contact_Person: Randy Nelson
- Contact_Position: Public Works Director
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 1900 Fourth Street North
- City: Wahpeton
- State_or_Province: ND
- Postal_Code: 58075
- Country: United States
- Contact_Voice_Telephone: 701-642-6565
- Contact_Electronic_Mail_Address: RandyN@wahpeton.com
- Hours_of_Service: 8am-5pm, Central Time
- Resource_Description: Iowa County Orthophotography Spring 2012
- Distribution_Liability:
-
In no event shall the creators, custodians, or distributors of
this information be liable for any damages arising out of its
use (or the inability to use it).
- Metadata_Reference_Information:
-
- Metadata_Date: 20121008
- Metadata_Contact:
-
- Contact_Information:
-
- Contact_Organization_Primary:
-
- Contact_Organization: City of Wahpeton
- Contact_Person: Randy Nelson
- Contact_Position: Public Works Director
- Contact_Address:
-
- Address_Type: mailing and physical address
- Address: 1900 Fourth Street North
- City: Wahpeton
- State_or_Province: ND
- Postal_Code: 58075
- Country: United States
- Contact_Voice_Telephone: 701-642-6565
- Contact_Electronic_Mail_Address: RandyN@wahpeton.com
- Hours_of_Service: 8am-5pm, Central Time
- Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
- Metadata_Standard_Version: FGDC-STD-001-1998
- Metadata_Access_Constraints: None
- Metadata_Use_Constraints: None
Generated by mp version 2.8.11 on Tue Dec 11 10:55:43 2012