Radiometric or visual consistency for Study Area One (SA1) was accomplished using a two-step image post processing procedure. The first step was Front-End Post Processing. Vexcel UltraMap image processing software was used to acomplish this goal. Primary front-end post processing within the UltraMap RawDataCenter uses UltraMap-AT to develop a consistent color adjustment with one or more sorties to create a Look-Up Table (LUT) setting an initial color, tone and contrast solutions for the raw post processed imagery. Upon analyzing and testing random images from different sorties, random images from each subsequent sortie were tested using this same LUT, once radiometric continuity within reasonable expectations was achieved, the LUT was applied to remainder of images, with no modifications. The UltraMap Radiometry module was used as final step of image processing to define final color of aerial images, where hotspots, haze and other atmospheric effects were removed or reduced. This technical approach was applied across all sorties for SA1 and it did achieve radiometric consistency within reasonable expectations across the entire study area. The second step of the process was Back-End Post Processing. Upon completing primary post processing within the UltraMap software, supplementary "back-end" image post processing was applied systematically to ensure radiometric continuity between each flight line, from sortie to sortie, across the entire project study area, and to further ensure compliance with the State specifications and "Land Cover Samples" image post processing guidelines. Back-End post processing to improve overall radiometric quality and continuity was accomplished using Adobe Photoshop 22.5.1.
Totally interactive mosaic tools and methods were used to provide complete seamless orthoimagery for Study Area One (SA1). An automated seamline generation tool was used to create initial mosaic polygons. Generated seamlines and resulting polygons were then manually reviewed, edited and digitized to provide the best and most complete mosaic result possible. All SA1 orthoimage tiles were full tiles, covering 5,000' x 5,000', with no void areas. All final orthoimage tiles were visually inspected for completeness, to ensure that no gaps or void areas exists. Consistent radiometry, feature distortion, artifacts, image motion, edge matching and accuracy were all checked to ensure compliance to the project scope of work and North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014.
Source_Information:
Source_Citation:
Citation_Information:
Originator: The Sanborn Map Company, Inc.
Publication_Date: 20240110
Title: Imagery Acquisition and Ground Control Plan, Attachment-C
Edition: 1.0
Geospatial_Data_Presentation_Form:
Microsoft Word DOC, UltraCam Eagle Flight Plan, Excel Spreadsheat (Photo position and control location)
Publication_Information:
Publication_Place: Pineville, NC
Publisher: The Sanborn Map Company, Inc.
Type_of_Source_Media: FTP
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2024
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: FLGCPLN
Source_Contribution:
The Imagery Acquisition and Ground Control Plan, Attachment-C, once approved by CGIA and NCDOT, provided the source data, materials and technical plan to execute the ground control and imagery acquisition phases outlined in Sub-Tasks 1.2 to 1.6 under the CO24 Scope of work.
Source_Information:
Source_Citation:
Citation_Information:
Originator: The Sanborn Map Company, Inc.
Publication_Date: 20240215
Title: Microsoft Vexcel UltraCAM Eagle M3 Digital Airborne Imagery
Edition: 1.0
Geospatial_Data_Presentation_Form: raster digital data
Publication_Information:
Publication_Place: Pineville, NC
Publisher: The Sanborn Map Company
Type_of_Source_Media: Solid-State Hard Drive
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2024
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: DAIMGRY
Source_Contribution:
The raw imagery captured with the Eagle M3 digital airborne imagery served as the foundation image component for Study Area 1 (SA1). The raw imagery was collected at an altitude of approximately 12,300' above sea level (ASL) elevation. The imagery was collected in a proprietary RAW image format at 12-bit resolution per pixel and post processed as a 4-band (RGBN) color, 8-bit, uncompressed TIFF raster image file, tiled at 256 with averaged overviews. The final post processed 8-bit TIFF images were used during the Aero-Triangulation, DEM update, Seamline generation and Orthoimagery production phases.
Source_Information:
Source_Citation:
Citation_Information:
Originator: The Sanborn Map Company, Inc.
Publication_Date: 20240215
Title: Airborne GPS and Inertial Measurement Unit (IMU) Data
Edition: 1.0
Geospatial_Data_Presentation_Form: tabular digital data
Publication_Information:
Publication_Place: Pineville, NC
Publisher: The Sanborn Map Company
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2024
Source_Currentness_Reference: ground conditions
Source_Citation_Abbreviation: AGPSIMU
Source_Contribution:
The Airborne GPS data provides accurate geodetic coordinates for the nadir point of each image at the precise time of exposure. The IMU data provides accurate omega, phi and kappa orientation angles representing the attitude of the sensor at the precise time of exposure for each image. The Airborne GPS coordinates and IMU orientation angle values play a key role to support the desired accuracy of the Aero-Triangulation process, by supplementing the field survey ground control, thus saturating the project study area with control. The Airborne GPS coordinates were expressed horizontally in NC SPC NAD83 (2011), US Survey Feet units, and vertically in NAVD 1988 (GEOID12A), US Survey Feet. The omega, phi and kappa IMU orientation angles were expressed in decimal degrees.
Source_Information:
Source_Citation:
Citation_Information:
Originator: The Sanborn Map Company, Inc.
Publication_Date: 20240607
Title: GPS Ground Control
Edition: 1.0
Geospatial_Data_Presentation_Form: tabular digital data
Publication_Information:
Publication_Place: Pineville, NC
Publisher: The Sanborn Map Company
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2022
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: GPSCTRL
Source_Contribution:
The GPS Ground Control provided precise geodetic coordinates and elevations for pre-paneled and photo-identifiable positions throughout Study Area 1 (SA1). These control point positions were measured along with pass and tie points on the imagery and used during the Aero-Triangulation (AT) measurement process. The precise coordinate values along with the GPSIMU data were then applied in an absolute AT adjustment in order to accurately control and geo-reference each block of photos. The AT adjustment was processed in bundle method and used to validate the control and check points used during the process. The precise ground control coordinates were also used during the accuracy quality control process. The locations of the pre-paneled and photo-identifiable points as they appeared in the final ortho-imagery were compared to their precise coordinates in Global Mapper 23 to ensure compliance with ASPRS Class I Horizontal accuracy requirements. The control coordinates were expressed horizontally in NC SPC NAD83 (2011), US Survey Feet and vertically in NAVD 1988 (GEOID12A), US Survey Feet.
Source_Information:
Source_Citation:
Citation_Information:
Originator: The Sanborn Map Company, Inc.
Publication_Date: 20200101
Title: 2020 Orthoimagery Ground Control-Check Points
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: NC Geodetic Survey
Type_of_Source_Media: FTP
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2020
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: 2020CKPT
Source_Contribution:
The 2020 Ground Control-Check Points provided by NCGS were utilized during the Aero-Triangulation phase and Horizontal Accuracy quality control task for Study Area 1 (SA1). The 2020 Ground Control Check Points also demonstrated reuse of data and provided redundancy to the 2024 project from the 2011 and 2012-2023 projects, while adding integrity to the final 2024 project outcome.
Source_Information:
Source_Citation:
Citation_Information:
Originator: NC Department of Transportation
Publication_Date: 20240607
Title: NCDOT Bridge Locations
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: NC Department of Transportation
Online_Linkage:
Type_of_Source_Media: Digital and/or Hardcopy
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20240607
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: BRDGLOC
Source_Contribution:
The NCDOT Bridge Location shapefile was utilized during sub-task 3.4, LiDAR DEM update and during Internal Level-1 Macro (IL1M) quality control review process to visit each bridge location in the orthoimagery within Study Area 1 (SA1) to ensure no distortion was introduced to the bridge, overpass or culvert by the original NC Floodplain Mapping LiDAR at each location.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Geospatial & Technology Management Office
Publication_Date: 20200101
Title:
NC Floodplain Mapping Program (FMP) LIDAR digital elevation model
Geospatial_Data_Presentation_Form: vector digital data
Type_of_Source_Media: Digital and/or Hardcopy
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2020
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: LIDAR_DEM
Source_Contribution:
The LIDAR digital elevation data used for the rectification of the orthophotos was provided by the Department of Public Safety, Division of Emergency Management, Office of Risk Management Office.
Source_Information:
Source_Citation:
Citation_Information:
Originator:
Department of Public Safety, Division of Emergency Management, Office of Risk Managment
Publication_Date: 20240301
Title: Tile Index
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital data
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20240301
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: INDEX
Source_Contribution:
The tile definition is used to cut orthorectified imagery into manageable, usable images. Each tile measures 5000' X 5000'.
Source_Information:
Source_Citation:
Citation_Information:
Originator: NC Geodetic Survey
Publication_Date: 20240301
Title: North Carolina County Boundaries
Edition: 1.0
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: NC Geodetic Survey
Type_of_Source_Media: digital download
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20240301
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: CB
Source_Contribution:
The county boundaries are used to select tiles by county for packaging imagery for offline distribution.
Process_Step:
Process_Description:
North Carolina Validation Range. The airborne acquisition systems used comprised of a twin engine aircraft, UltraCam Eagle M3 Digital Airborne Sensor, Applanix Inertial Navigation System and Track-Air flight management system. One system configurations was used: aircraft N910FC camera Eagle 5 SN 2156. These systems were approved by acquiring digital airborne imagery, airborne GPS and IMU data over the North Carolina Validation Range in Surry County, NC. The Sanborn Map Company, Inc. processed the imagery and aero-triangulation as a mini project or expedited sensor system validation procedure including project deliverables, reports or selective tabular data under the NC scope of work. The Aero-Triangulation (AT) results and Orthoimage tiles for each Validation Range mission were reviewed and verified by NCDOT and NCGS for compliance with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 1, 2009 and ASPRS Class I horizontal accuracy requirements prior to execution of the CO24 project. The processes and results for each acquisition system verified under the Validation Range procedure were reported and documented in or under portions of Attachment C, D, and E. These Attachments are obtainable from CGIA.
Process_Date: 20240112
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Imagery Acquisition Flight and Ground Control Planning. Sanborn Photogrammetrists and Surveyors planned and identified flight and control plans for SA1 in compliance with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 1, 2014. Preliminary flight and control plans in the form of Attachment-C were submitted to CGIA and NCDOT for approval prior to execution of CO24 Project Study Area 1. The flight and control plan for SA1 detailed in Attachment-C is obtainable from CGIA. Flight plans were based on north-south oriented flight lines. The Flight and Control Plan included one Aero-Triangulation (AT) block used for entire SA1.
Source_Used_Citation_Abbreviation: FLGCPLN
Process_Date: 20240110
Source_Produced_Citation_Abbreviation: DAIMGRY
Source_Produced_Citation_Abbreviation: GPSCTRL
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Pre-Paneling and GPS Ground Control Survey. Sanborn under the direction of Sanborn's NC-PLS used existing points set as control from the 2020 NC Orthoimagery Project. Control points were used as check points during the initial Aero-Triangulation (AT) process and later as control points in the final AT process. All surveyed control points were referenced horizontally to NC SPC, NAD83 (NA2011) US Survey Feet, and vertically to NAVD88 (GEIOD12A), US Survey Feet. A Control Surveys Report, Attachment C-1 was signed and sealed by the North Carolina Professional Land Surveyor (PLS) in responsible charge and was submitted to CGIA and NCGS for approval and acceptance. Attachment C-1 is obtainable from CGIA.
Process_Date: 20240405
Source_Produced_Citation_Abbreviation: GPSCTRL
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Eagle Digital Airborne Imagery, Airborne GPS and IMU raw data acquisition. With consideration to geographic location, vegetation, weather conditions, PDOP, ground control and other relative ground or atmospheric conditions, the Digital Aerial Imagery, Airborne GPS and IMU raw data was acquired in the most efficient time frame possible beginning February 4, 2024 and ending on February 15, 2024. A total of five (5) sorties were performed for Study Area 1 (SA1). Sanborn acquired digital aerial imagery utilizing one (1) UltraCam Eagle M3 digital airborne sensor installed on top of Track-air stabilizers mounted and controlled by track-air flight management system. Raw Airborne GPS and IMU data was collected utilizing Applanix INS system with a Dual Frequency L1/L2+ GPS Receiver and LV200 Inertial Position and Orientation System. Airborne acquisition was conducted during leaf off, cloud free, 33 degree sun angle conditions, in compliance with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014. Airborne acquisition tasks were detailed in Attachment-D submitted to CGIA and NCDOT for acceptance and approval. Attachment D is obtainable from CGIA.
Process_Date: 20240215
Source_Produced_Citation_Abbreviation: DAIMGRY
Source_Produced_Citation_Abbreviation: AGPSIMU
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Digital Airborne Imagery Post Processing, The RAW digital airborne imagery was post processed using a two-step image post processing procedure with concern for radiometric and visual consistency across Study Area 1 (SA1) in consideration of exploitation land cover samples provided by CGIA and NCDOT. The first step was Front-End Post Processing utilizing UltraMap-AT and Radiometry software to develop look-up-tables (LUTs) to provide initial color, tone and contrast solutions for the raw post processed imagery. Upon analyzing and testing random images to create a Look-Up Table from different sorties; random images from each subsequent sortie were tested using this same LUT, if radiometric continuity within reasonable expectations was achieved, the LUT was applied with no modifications. This technical approach was applied across all sorties for SA1 and did achieve radiometric consistency within reasonable expectations across the entire study area. The second step of the process was to ensure radiometric continuity between each flight line, from sortie to sortie, across the entire project study area, and to further ensure compliance with the State specifications and the "Land Cover Samples" image post processing guidelines. Post processing to improve overall radiometric quality and continuity was accomplished using Adobe Photoshop 22.5.1. Systematic and or variable adjustments for color, tone and contrast were tested and applied to individual images, flight lines and entire sorties as necessary to correct issues of radiometric inconsistency of unreasonable or unacceptable probability. Final digital airborne images were post processed as a 4-band (RGBN) color, 8-bit, uncompressed TIFF raster image file, tiled at 256 with averaged overviews. Digital airborne image post processing was conducted in compliance with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014 and the CO24 "Land Cover Samples" image Post processing guidelines.
Source_Used_Citation_Abbreviation: FLGCPLN
Process_Date: 20220413
Source_Produced_Citation_Abbreviation: DAIMGRY
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
To process the Airborne GPS-IMU data for this project, Sanborn utilized Applanix POSPac – Mobile Mapping Suite processing software, version 8.8; specifically developed for accurate Direct Georeferencing of airborne sensors.The POSPac MMS software computes a combined solution of position and attitude of the airborne sensor by processing the raw IMU and GPS data collected with a POS/AV system during the flight, along with recorded GPS time of the events when the digital sensor or aerial camera trigged a photo, within milli-second precision. With the use of differential correction techniques and Kalman filter, POSPac computes the GPS (Global Positional System) solution for the aerial path, and blends it with the inertial data, collected with the IMU (Inertial Measurement Unit). The differential correction of the Airborne GPS data is accomplished in the first 3 to 5 minutes of the processing and carried throughout the processing of entire mission. With POSPac, a solution is computed in a forward (begin-to-end) and reverse (end-to-begin) mode, and the variation between each mode, together with satellite configuration, is used for statistical evaluation of the quality and accuracy of the data. The use of AGPS-IMU allows for a positional accuracy of each aerial photo within 10cm or better of its real position. Applanix POSPac MMS version 8.1 PP-RTX uses satellite data to apply real time corrections. PP-RTX is a Precise Point Positioning (PPP) technology. The satellites (geostationary L-band satellites) retrieve the data and transmit it through the L-band range of frequencies. The corrections are derived from Trimble's global network of base stations and applied using advanced algorithms on the rover receiver. Upon extraction of all files belonging to one mission (or sortie), POSPac was used to retrieve the positional corrections via satellite around the aerial mission area. The positional corrections are received from Trimble's global network of base stations and advanced algorithms are applied. Sanborn used POSPac MMS with IN-Fusion technology for this project. The IN-fusion PP-RTX technology uses the L-band frequencies of satellites as reference for the differential processing and computation of coordinate for each epoch of the GPS-IMU dataset. After final GPS-IMU processing is completed; entire mission can be viewed and selected in many different ways including the 2D Plan View, 3D View, and Points Spreadsheet for final review. The processed GPS-IMU was combined with the GPS Event time for each photo. The GPS Event Time is a sequential time, stored in seconds of GPS time relative to the specific GPS week. GPS time is stored in seconds with 6 decimal places. The Exterior Orientation file was exported based on the interpolated position at the event-time for each photo, with all photo centers in State Plane NC Coordinate System, NAD83/2011 adjustment. GPS-IMU post processing was conducted in compliance with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014. GPS-IMU post processing procedures and results were detailed in Attachment-E, per AT block, submitted to CGIA and NCDOT for acceptance and approval. Attachment E is obtainable from CGIA. The final Airborne GPS coordinates were expressed horizontally in NC SPC NAD83 (2011), US Survey Feet and vertically in NAVD 1988 (GEOID12A), US Survey Feet. The omega, phi and kappa IMU orientation angles were expressed in decimal degrees.
Source_Used_Citation_Abbreviation: AGPSIMU
Source_Used_Citation_Abbreviation: GPSCTRL
Source_Used_Citation_Abbreviation: 2020CKPT
Process_Date: 20220218
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Digital Softcopy Aero-Triangulation. Sanborn completed all phases of Digital Softcopy Aero-Triangulation (AT) across Study Area 1 (SA1) from May 24, 2024. The Aerotriangulation is a process of densification of control points for accurate georeferencing of a block of images. Few ground control survey points combined with the GPS post-processed photo center position, are used as source of ground control coordinate for the aerotriangulation process. In the Aerotriangulation phase, photogrammetric image points are measured on overlap areas of each aerial photo and its image coordinate stored. A bundle adjustment is computed and the ground coordinate is computed for all points measured on the block of aerial photos. The standard workflow procedure for aerotriangulation starts with the release of the EO files from the GPS-IMU processing. Softcopy workstations were used for the aerotriangulation phase. Coordinates of targeted ground control points were loaded and measured on each photo where it appears. The GPS-IMU direct exterior orientation was combined with conventional ground control in an AT- bundle adjustment for each block of photos. Airborne GPS photo centers were matched with the image names and the EO (Exterior Orientation) file used to load the AT (aerotriangulation) files. Inpho MATCH-AT was used to perform automated matching measurement of photogrammetric points, for aerial triangulation process and for final photo orientation. MATCH-AT automated tie point selection and multi-ray point matching provide efficient point match. MATCH-AT was used for manual measurements, processing and bundle adjustment, GNSS and IMU support, allowing precise aerial image triangulation, with high performance, fast processing and fully automated processing. Pass/tie points between frame images and flight lines were automatically matched with Inpho MATCH-AT, followed by manual measurement of additional points at optimal locations. All ground control points and checkpoints were manually measured on the images. This MATCH-AT solution forms the basis for the accuracy final orthophotos to be derived for this project. The final step in the Aerotriangulation included the ground control surveyed XYZ positions to constrain the block adjustment. The RMSE at the ground control points and the XYZ misfits were analyzed. Additional checkpoints where provided by CGIA and measured on the images where it appeared. The aerotriangulation solution was processed and adjusted coordinates of checkpoints computed and compared. A final bundle adjustment was then processed using all control points to support the final image orientation. The final pass, tie and control point coordinates derived from the AT were expressed horizontally in NC SPC NAD83 (2011), US Survey Feet and vertically in NAVD 1988 (GEOID12A), US Survey Feet. The exterior orientation parameters X, Y and Z were expressed horizontally in NC SPC NAD83 (2011), US Survey Feet and vertically in NAVD 1988 (GEOID12A), US Survey Feet. The exterior orientation angles omega, phi and kappa were expressed in decimal degrees. The AT process was conducted in compliance with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014. AT procedures and results were detailed in Attachment-E, per AT block, submitted to CGIA and NCDOT for acceptance and approval. Attachment E is obtainable from CGIA.
Source_Used_Citation_Abbreviation: DAIMGRY
Source_Used_Citation_Abbreviation: AGPSIMU
Source_Used_Citation_Abbreviation: GPSCTRL
Process_Date: 20220524
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
LiDAR DEM Review and Update. Sanborn reviewed the NC Floodplain Mapping LiDAR elevation data (as needed) at a density level sufficient to accurately represent the shape of the ground and to meet the required ASPRS Class I horizontal accuracy for cultural features at a design scale of 1:2,400 (1'= 200') where the limiting RMSE in either X or Y is not greater than 1.5'. NCDOT provided a construction history shapefile which was converted to Microstation V8 and utilized during the NC Floodplain Mapping LiDAR review and update task. The Microstation V8 construction history data was referenced to the NC Floodplain Mapping LiDAR bare earth data in 3D utilizing Intergraph ImageStation Stereo Display (ISSD).
Source_Used_Citation_Abbreviation: LIDAR_DEM
Source_Used_Citation_Abbreviation: DAIMGRY
Process_Date: 20220422
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc.
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Preliminary Orthoimage Rectification. Sanborn utilized OrthoPro to process the digital orthophoto imagery. Color balanced and adjusted by Sanborn, aerial photos were orthorectified using the final aero-triangulation (AT) data files processed by Sanborn and the Floodplain Map LiDAR DEM elevation data to produce preliminary orthorectified images. The preliminary orthoimages were used for the purpose of visual internal quality control and for manual seamline polygon digitizing. During the manual seamline digitizing process, each image was cursory inspected visually for overall image quality, distortion due to erroneous LiDAR data, artifacts, clouds, cloud shadows, smoke or any other anomaly that would not comply with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014. The NCDOT bridge shapefile was also used during this step to visit each bridge, overpass or major culvert location within the project area to determine if special DEM treatment would be necessary to remove distortion from these features. Any problem or issue detected during this process step along with its predicted resolution was recorded graphically in Global Mapper 23 and exported to a SHP file. The preliminary orthoimages were used to identify any correction needed on the DEM, to evaluate and confirm quality of aerotriangulation results, and for overall inspection of color match between all aerial images. Sanborn performed full Quality Assurance and Quality Control of every tile produced.
Source_Used_Citation_Abbreviation: DAIMGRY
Source_Used_Citation_Abbreviation: LIDAR_DEM
Source_Used_Citation_Abbreviation: BRDGLOC
Process_Date: 20220503
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Seamline Polygon Generation. Sanborn processed automated seamline cut between each preliminary orthoimage and performed a visual inspection to determine accepted lines and where needed, a most precise and logical location for the seamline was manually digitized between all orthoimages in order to produce the best possible mosaic result across Study Area 1 (SA1). The manually digitized seamlines and resulting seamline polygons were again visually inspected, refined and updated throughout the remaining production and quality control process performed by Sanborn. Final seamline polygon data was delivered in ESRI shapefile format with the following attributes: ProjectID, StdAreaID, VendorID, STRIP, EXPOSURE_ID and ACQUISITION_DATE.
Source_Used_Citation_Abbreviation: DAIMGRY
Process_Date: 20240829
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28226
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Final Orthoimage Rectification. Sanborn utilized OrthoPro to process the final ortho-rectified exploitation imagery, using the final aero-triangulation (AT) data files and updated LiDAR DEM elevation data, to produce final orthorectified images. Final orthoimages incorporated all resolutions for any distortion due to erroneous LiDAR data, artifacts, clouds, cloud shadows, smoke or any other anomaly that would not comply with the North Carolina Technical Specifications for Digital Orthophoto Base Mapping, adopted October 2014; detected and recorded during the internal cursory inspection of the preliminary orthoimages, manual seamline digitizing or comparing the NCDOT bridge location data. The final orthoimages were used in the final mosaic process step.
Source_Used_Citation_Abbreviation: LIDAR_DEM
Source_Used_Citation_Abbreviation: BRDGLOC
Process_Date: 20240712
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Orthoimage Tile Mosaic Processing. Sanborn utilized OrthoPro to edit digitized seamlines and produce seamline polygons to be applied to each individual final orthorectified exploitation image during the final mosaic process step. A product definition file was used with a 5,000' x 5,000' orthoimage tile layout required for Study Area 1 (SA1). The final orthoimages, seamline polygons and product definitions were processed in the final mosaic process step to output the final 5,000' x 5,000' orthoimage tiles, which incorporates final mosaic color and tone balance processing. All SA1 final orthoimages, mosaic polygons and product definitions were processed simultaneously to ensure the final mosaic output, edge matching, color and tone balancing was absolutely consistent across the entire study area. The orthoimage tiles were named using the required file naming convention (e.g. OF6i0_37_000_10670103_20220130_0209R0.tif). The orthoimage tiles were subject to four (4) different levels of quality control. Resolutions for problems detected during these levels of quality control were documented and reported in VOICE and Attachment-F. Delivery of the final orthoimage tiles and ancillary data was documented and reported in Attachment-F. Attachment-F is obtainable from CGIA.
Source_Used_Citation_Abbreviation: DAIMGRY
Source_Used_Citation_Abbreviation: INDEX
Source_Used_Citation_Abbreviation: BRDGLOC
Source_Used_Citation_Abbreviation: 2010CKPT
Process_Date: 20240712
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28134
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Level-1 Macro Quality Control Review. Sanborn performed 100% Quality-Assurance & Quality-Control (QA&QC) on all ortho tiles produced during previous process steps, to guarantee all specifications and requirements of the projects were met. The final ortho tiles were corrected for any anomaly or remaining issue and delivered to the service provider selected by CGIA to host the orthophoto tiles for visual inspection by the County, NCDOT and CGIA reviewers.
Process_Date: 20220713
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: The Sanborn Map Company, Inc
Contact_Person: Christian Ulloa
Contact_Position: Manager of Operations
Contact_Address:
Address_Type: mailing and physical
Address: 600 Towne Centre Blvd, Suite 401
City: Pineville
State_or_Province: NC
Postal_Code: 28226
Country: USA
Contact_Voice_Telephone: 704-347-4552
Contact_Electronic_Mail_Address: christian@sanborn.com
Process_Step:
Process_Description:
Visual quality control consisted of several levels of review. Project contractors conducted both initial macro and micro level review of all data. After the data was released to the State, NCDOT reviewed 30% of each county's ortho tiles, CGIA reviewed 5% and the counties had the ability to review the full county worth of data and were provided a list of 25% of tiles to review. CGIA then reviewed all submitted issues and submitted those considered to be in scope to project guidelines to the contractors for review. Contractor teams reviewed these submitted issues and assessed whether a fix was feasible. Tiles that were repaired were validated by NCDOT to ensure that fixes were made and did not introduce new issues. All review by NCDOT, CGIA, and other end-users as well as contractors' assessment and evaluation was conducted in an cloud-hosted environment accessible through an online webservice INSITE.
Process_Date: 20240916
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: NC Center for Geographic Information and Analysis
Contact_Person: Benjamin Shelton
Contact_Position: Project Manager
Contact_Address:
Address_Type: mailing address
Address: 20322 Mail Service Center
City: Raleigh
State_or_Province: NC
Postal_Code: 27699-0322
Country: USA
Contact_Voice_Telephone: 919-754-6377
Contact_Facsimile_Telephone: 919-715-8551
Contact_Electronic_Mail_Address: ben.shelton@nc.gov
Process_Step:
Process_Description:
Horizontal quality control consists of utilizing quality control test points obtained from an independent source of higher accuracy of the tested product. The purpose of the quality control test is to determine the horizontal accuracy of the product and produce a report documenting the result of the accuracy test.
Source_Used_Citation_Abbreviation: GPSCTRL
Source_Used_Citation_Abbreviation: 2020CKPT
Process_Date: 20240524
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: NC Geodetic Survey
Contact_Person: Gary Thompson
Contact_Position: Director
Contact_Address:
Address_Type: physical
Address: 4105 Reedy Creek Rd Bowers Building
City: Raleigh
State_or_Province: NC
Postal_Code: 27607
Country: USA
Contact_Voice_Telephone: 919-948-7844
Contact_Facsimile_Telephone: 919-733-4407
Contact_Electronic_Mail_Address: gary.thompson@ncdps.gov
Process_Step:
Process_Description:
20:1 MRSID Tile Creation- NCDOT created a standalone 20:1 compressed copy of each orthoimagery tile delivered in the 2024 project. Lizardtech software was used to compress each TIFF tile to a 20:1 MRSID formatted file. The resulting MRSID files maintain the same file name as the TIFF tiles.
Process_Date: 2024
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: NC Department of Transportation
Contact_Person: Keith Johnston
Contact_Position: State Photogrammetric Engineer
Contact_Address:
Address_Type: mailing
Address: 1585 Mail Service Center
City: Raleigh
State_or_Province: NC
Postal_Code: 27699-1585
Country: USA
Contact_Voice_Telephone: 919.707.7093
Contact_Facsimile_Telephone: 919.250.4176
Contact_Electronic_Mail_Address: kjohnston@ncdot.gov
Process_Step:
Process_Description:
50:1 MRSID Countywide Mosaic Creation- NCDOT created a standalone 50:1 compressed file of all of the imagery that intersects each county. Lizardtech software was used to merge all of the 20:1 MRSID tiles into a unified singular 50:1 compressed file containing all imagery for a county, excluding any sensitive military areas where necessary.
Process_Date: 2024
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: NC Department of Transportation
Contact_Person: Keith Johnston
Contact_Position: State Photogrammetric Engineer
Contact_Address:
Address_Type: mailing
Address: 1585 Mail Service Center
City: Raleigh
State_or_Province: NC
Postal_Code: 27699-1585
Country: USA
Contact_Voice_Telephone: 919.707.7093
Contact_Facsimile_Telephone: 919.250.4176
Contact_Electronic_Mail_Address: kjohnston@ncdot.gov
Process_Step:
Process_Description:
CGIA product validation process: Before delivery of data to each county, CGIA validated that each county would receive all TIFF and MRSID 20:1 compression tiles that intersect that county and ensured that the files were named correctly, were correctly spatially referenced, and validated that each drive contains a countywide MRSID 50:1 compression mosaic, an index shapefile denoting the location of each tile, a seamline polygon that denotes the location and date of each discrete image used to create the imagery, project documentation about the ortho creation process, any updated elevation information, and both MRSID 20:1 compression tiles and a MRSID 50:1 mosaic for each neighboring county.
Process_Date: 2024
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: NC Center for Geographic Information and Analysis
Contact_Person: Benjamin Shelton
Contact_Position: Project Manager
Contact_Address:
Address_Type: mailing address
Address: 20322 Mail Service Center
City: Raleigh
State_or_Province: NC
Postal_Code: 27699-0322
Country: USA
Contact_Voice_Telephone: 919-754-6377
Contact_Facsimile_Telephone: 919-715-8551
Contact_Electronic_Mail_Address: ben.shelton@nc.gov
Process_Step:
Process_Description: Metadata imported.
Process_Date: 20241015