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Metadata:
Identification_Information:
Citation:
Citation_Information:
Originator: USDA-FSA-APFO Aerial Photography Field Office
Publication_Date: 20121002
Title: NAIP Digital Ortho Photo Image
Geospatial_Data_Presentation_Form: remote-sensing image
Publication_Information:
Publication_Place: Salt Lake City, Utah
Publisher: USDA-FSA-APFO Aerial Photography Field Office
Description:
Abstract:
This data set contains imagery from the National Agriculture Imagery Program (NAIP). NAIP acquires digital ortho imagery during the agricultural growing seasons in the continental U.S.. A primary goal of the NAIP program is to enable availability of of ortho imagery within one year of acquisition. NAIP provides four main products: 1 meter ground sample distance (GSD) ortho imagery rectified to a horizontal accuracy of within +/- 5 meters of reference digital ortho quarter quads (DOQQ's) from the National Digital Ortho Program (NDOP); 2 meter GSD ortho imagery rectified to within +/- 10 meters of reference DOQQs; 1 meter GSD ortho imagery rectified to within +/- 6 meters to true ground; and, 2 meter GSD ortho imagery rectified to within +/- 10 meters to true ground. The tiling format of NAIP imagery is based on a 3.75' x 3.75' quarter quadrangle with a 300 meter buffer on all four sides. NAIP quarter quads are formatted to the UTM coordinate system using NAD83. NAIP imagery may contain as much as 10% cloud cover per tile.
Purpose:
NAIP imagery is available for distribution within 60 days of the end of a flying season and is intended to provide current information of agricultural conditions in support of USDA farm programs. For USDA Farm Service Agency, the 1 meter GSD product provides an ortho image base for Common Land Unit boundaries and other data sets. The 1 meter NAIP imagery is generally acquired in projects covering full states in cooperation with state government and other federal agencies who use the imagery for a variety of purposes including land use planning and natural resource assessment. With an annual cycle, NAIP is also used for disaster response often providing the most current pre-event imagery. While suitable for a variety of uses the 2 meter GSD NAIP imagery is primarily intended to assess crop condition and compliance to USDA farm program conditions. The 2 meter imagery is generally acquired only for agricultural areas within state projects.
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20120706, 20120712, 20120721, 20120725, 20120807, 20120817, or 20120821
Currentness_Reference: Ground Condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Irregular
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -73.7500
East_Bounding_Coordinate: -71.7500
North_Bounding_Coordinate: 42.0625
South_Bounding_Coordinate: 40.9375
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: farming
Theme_Keyword: Digital Ortho rectified Image
Theme_Keyword: Ortho Rectification
Theme_Keyword: Quarter Quadrangle Centered
Theme_Keyword: NAIP
Theme_Keyword: Aerial Compliance
Theme_Keyword: Compliance
Place:
Place_Keyword_Thesaurus: Geographic Names Information System
Place_Keyword: CT
Place_Keyword:
Place_Keyword:
Place_Keyword:
Place_Keyword:
Place_Keyword:
Place_Keyword:
Access_Constraints: There are no limitations for access.
Use_Constraints:
Imagery may be replaced to address defects found in a small number of products through quality assurance processes. Imagery containing defects that require the acquisition of new imagery, such as excessive cloud cover, specular reflectance, etc., will not be replaced within a NAIP project year.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Aerial Photography Field Office (APFO)
Contact_Address:
Address_Type: mailing and physical address
Address: 2222 West 2300 South
City: Salt Lake City
State_or_Province: Utah
Postal_Code: 84119-2020
Country: USA
Contact_Voice_Telephone: 801-844-2922
Contact_Facsimile_Telephone: 801-956-3653
Contact_Electronic_Mail_Address: apfo.sales@slc.usda.gov
Browse_Graphic:
Browse_Graphic_File_Name: None
Browse_Graphic_File_Description: None
Browse_Graphic_File_Type: None
Native_Data_Set_Environment: Unknown
Data_Quality_Information:
Logical_Consistency_Report:
NAIP 3.75 minute tile file names are based on the USGS quadrangle naming convention.
Completeness_Report: None
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
FSA Digital Orthophoto Specs.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: USDA-FSA-APFO Aerial Photography Field Office
Publication_Date: approximately 201210
Title:
Geospatial_Data_Presentation_Form: remote-sensing image
Type_of_Source_Media: UnKnown
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 20120706-20120821
Source_Currentness_Reference:
Aerial Photography Date for aerial photo source.
Source_Citation_Abbreviation: Georectifed Image
Source_Contribution: Digital Georectifed Image.
Process_Step:
Process_Description:
DOQQ Production Process Description USDA FSA APFO NAIP Program 2012 State: Connecticut
The imagery was collected using ADS40-SH51,ADS40-SH52, and ASD40-SH81 digital sensors. Collection was performed using a combination of twin-engine aircraft flying at 22,500 or 27,000 ft above mean terrain with 25% sidelap, giving the collected data nominal ground sampling distance of 0.7 meters. Based-upon the CCD Array configuration present in the ADS40 digital sensor, imagery for each flight line is 12,000-pixels in width. Red, Green, Blue, Near-Infrared and Panchromatic image bands were collected.

Collected data was downloaded to portable hard drives and shipped to the processing facility daily. Raw flight data was extracted from external data drives using GPro software. Airborne GPS / IMU data was post-processed using IPAS, PosPac and/or TerraPos software and reviewed to ensure sufficient accuracy for project requirements.

Using Pictovera software, planar rectified images were generated from the collected data for use in image quality review. The planar rectified images were generated at five meter resolution using a two standard deviation histogram stretch. Factors considered during this review included but were not limited to the presence of smoke and/or cloud cover, contrails, light conditions, sun glint and any sensor or hardware-related issues that potentially could result in faulty data. When necessary, image strips identified as not meeting image quality specifications were re-flown to obtain suitable imagery.

Aero triangulation blocks were defined primarily by order of acquisition and consisted of four to seventeen strips. Image tie points providing the observations for the least squares bundle adjustment were selected from the images using an auto correlation algorithm. Photogrammetric control points consisted of photo identifiable control points, collected using GPS field survey techniques. The control points were loaded in to a softcopy workstation and measured in the acquired image strips. A least squares bundle adjustment of image pass points, control points and the ABGPS was performed to develop an aero triangulation solution for each block using Pictovera software.
Upon final bundle adjustment, the triangulated strips were ortho-rectified to the DEM. Digital elevation models (DEM) auto-correlated from imagery acquired for project items will be used in the orthorectification process. The PictoVera autocorrelation module is used to generate digital surface model (DSM) mass points for each survey line. The autocorrelation module uses an APM algorithm to measure mass points from the forward, nadir, and backward images; searching in the three images throughout the entire width and length of each flightline for matching features. The DSM mass points will model the ground surface and above ground features, and must be filtered to a digital terrain model (DTM) representing only ground features for use in orthorectification. PremierGeo uses the SimActive Correlator 3D software to generate the required DTM from the PictoVera DSM. Correlator 3D uses geometric algorithms to identify and filter above ground features from the DSM based on size and shape. The filtered DTM is then interpolated to a regularly gridded DEM for use in the PictoVera rectification module. The DEM is reviewed for any elevation anomalies that would introduce image smearing during orthorectification, and manual edits made as necessary to remove any anomalies.

Positional accuracy was reviewed in the rectified imagery by visually verifying the horizontal positioning of the known photo-identifiable survey locations using ArcGIS software.
The red, green, and blue bands were combined to generate a final ortho-rectified image strip. The ADS40 sensor collects twelve bit image data which requires radiometric adjustment for output in standard eight bit image channels. The ortho- rectified image strips were produced with the full 12 bit data range, allowing radiometric adjustment to 8 bit range to be performed on a strip by strip basis during the final mosaicking steps.
The imagery was mosaicked using manual seam line generation in Orthovista Seam Editor (OVSE). The 12 bit data range was adjusted for display in standard eight bit image channels by defining a piecewise histogram stretch using OrthoVista software. A constant stretch was defined for each image collection period, and then strip by strip adjustments were made as needed to account for changes in sun angle and azimuth during the collection period. Strip adjustments were also made to match the strips histograms as closely as possible to APFO specified histogram metrics and color balance requirements. Automated balancing algorithms were applied to account for bi- directional reflectance as a final step before the conversion to 8 bit data range.
Process_Date: approximately 201210
Spatial_Data_Organization_Information:
Indirect_Spatial_Reference: CT
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Pixel
Row_Count: 1
Column_Count: 1
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: Universal Transverse Mercator
Universal_Transverse_Mercator:
UTM_Zone_Number: 18 or 19
Transverse_Mercator:
Scale_Factor_at_Central_Meridian: 0.9996
Longitude_of_Central_Meridian: -75.0 (zone 18) or -69.0 (zone 19)
Latitude_of_Projection_Origin: 0.0
False_Easting: 500000
False_Northing: 0.0
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 1
Ordinate_Resolution: 1
Planar_Distance_Units: meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80 (GRS 80)
Semi-major_Axis: 6378137
Denominator_of_Flattening_Ratio: 298.257
Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview:
32-bit pixels, 4 band color(RGBIR) values 0 - 255
Entity_and_Attribute_Detail_Citation: None
Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Supervisor Customer Services Section
Contact_Organization:
USDA-FSA-APFO Aerial Photography Field Office
Contact_Address:
Address_Type: mailing and physical address
Address: 2222 West 2300 South
City: Salt Lake City
State_or_Province: Utah
Postal_Code: 84119-2020
Country: USA
Contact_Voice_Telephone: 801-844-2922
Contact_Facsimile_Telephone: 801-956-3653
Contact_Electronic_Mail_Address: apfo.sales@slc.usda.gov
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).
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: GeoTIFF - Georeferenced Tagged Image File Format
Format_Information_Content: Multispectral 4-band
Digital_Transfer_Option:
Offline_Option:
Offline_Media: CD-ROM
Recording_Format: ISO 9660 Mode 1 Level 2 Extensions
Fees:
Contact the Aerial Photography Field Office for more information
Resource_Description:
Metadata_Reference_Information:
Metadata_Date: approximately 201210
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
USDA-FSA-APFO Aerial Photography Field Office
Contact_Address:
Address_Type: mailing and physical address
Address: 2222 West 2300 South
City: Salt Lake City
State_or_Province: Utah
Postal_Code: 84119-2020
Country: USA
Contact_Voice_Telephone: 801-844-2922
Metadata_Standard_Name:
Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998