Orthorectified Photomosaic Metadata

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Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: U.S.G.S

Publication_Date: Unknown

Title: Fort Union Trading Post National Historic Site Vegetation Mapping Project - Orthorectified Photomosaic

Online_Linkage: <http://biology.usgs.gov/npsveg/ftp/vegmapping/fous/fousortho.zip>

Geospatial_Data_Presentation_Form: remote-sensing image

Description:

Abstract:

Orthophotos combine the image characteristics of a photograph with the geometric qualities of a map. The primary digital orthophoto quarter quadrangle (DOQQ) is a 1-meter ground resolution quarter-quadrangle (3.75-minutes of latitude by 3.75-minutes of longitude) image cast on the Universal Transverse Mercator Projection (UTM) on the North American Datum of 1983 (NAD83). The geographic extent of a DOQQ is approximate to one quarter of a standard USGS 7.5-minute quadrangle. This image has been clipped to the area around KNRI. The radiometric image brightness values are stored as 256 gray levels ranging from 0 to 255. Image data are stored in TIFF format and clipped to the minimum bounding rectangle for the quarter-quadrangle to reduce file size.

Purpose:

DOQQ's serve a variety of purposes, from interim maps to field references for earth science investigations and analysis. A DOQQ is useful as a layer of a geographic information system and as a tool for development and revision of GIS databases.

Time_Period_of_Content:

Time_Period_Information:

Single_Date/Time:

Calendar_Date: Unknown

Currentness_Reference: ground condition

Status:

Progress: Complete

Maintenance_and_Update_Frequency: Irregular

Spatial_Domain:

Description_of_Geographic_Extent: Fort Union Trading Post National Historic Site and environs

Bounding_Coordinates:

West_Bounding_Coordinate: -104.069717

East_Bounding_Coordinate: -104.006046

North_Bounding_Coordinate: 48.028842

South_Bounding_Coordinate: 47.974197

Keywords:

Theme:

Theme_Keyword_Thesaurus: None

Theme_Keyword: rectified image

Theme_Keyword: 1-meter orthophoto

Theme_Keyword: 3.75- x 3.75-minute orthophoto

Theme_Keyword: aerial photograph

Theme_Keyword: DOQ

Theme_Keyword: DOQQ

Theme_Keyword: orthophoto

Theme_Keyword: orthophotograph

Theme_Keyword: quarter-quadrangle orthophoto

Theme_Keyword: rectified photograph

Access_Constraints: None

Use_Constraints: None

Point_of_Contact:

Contact_Information:

Contact_Person_Primary:

Contact_Organization: U.S. Bureau of Reclamation

Contact_Person: David Salas

Contact_Position: Project Manager

Contact_Address:

Address_Type: Mailing Address

Address: P.O. Box 25007

City: Denver

State_or_Province: Colorado

Postal_Code: 80225

Country: USA

Contact_Voice_Telephone: 303-445-3619

Contact_Electronic_Mail_Address: desalas@do.usbr.gov

Native_Data_Set_Environment:

Microsoft Windows NT Version 4.0 (Build 1381) Service Pack 6; ESRI ArcCatalog 8.2.0.700

Data_Quality_Information:

Attribute_Accuracy:

Attribute_Accuracy_Report:

The USGS reports that during photographic reproduction of the source photography, limited analog dodging is performed to improve image quality. The diapositive is inspected to insure clarity and radiometric uniformity. Diapositive image brightness values are collected with a minimum of image quality manipulation. Image brightness values may deviate from brightness values of the original imagery due to image value interpolation during the scanning and rectification processes. Radiometry is verified by visual inspection of the digital orthophoto quadrangle with the original unrectified image to determine if the digital orthophoto has the same or better image quality as the original unrectified input image. Systematic radiometric differences can be detected between adjacent DOQQ files due primarily to differences in source photography capture dates and sun angles of aerial photography along flight lines. These differences can be observed in an image's general lightness or darkness when compared to adjacent DOQQ images. In processing this data the Bureua of Reclamation's GIS and Remote Sensing Group did not alter the attribute accuracy.

Logical_Consistency_Report:

The USGS reports that the DOQQ header data and image file sizes are validated by the Tape Validation System (TVS) software prior to archiving in the National Digital Cartographic Data Base (NDCDB). This validation procedure assures correct physical format and field values for header record elements. Logical relationships between header record elements are tested. In processing this data the Bureua of Reclamation's GIS and Remote Sensing Group did not alter the attribute accuracy.

Completeness_Report:

The USGS reports that DOQQ imagery is visually inspected for completeness to ensure that no gaps or image misplacement exists in the 3.75' image. In processing this data the Bureua of Reclamation's GIS and Remote Sensing Group did not alter the attribute accuracy.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

The USGS reports that the DOQQ horizontal positional accuracy and the assurance of that accuracy depends, in part, on the accuracy of the data inputs to the rectification process. These inputs consist of the digital elevation model (DEM), aerotriangulation control and methods, the photo source camera calibration, scanner calibration, and aerial photographs that meet National Aerial Photography Program (NAPP) standards. The vertical accuracy of the verified USGS format DEM is equivalent to or better than a USGS level 1 or 2 DEM, with a root mean square error (RMSE) of no greater than 7.0 meters. Field control is acquired by third order class 1 or better survey methods sufficiently spaced to meet National Map Accuracy Standards (NMAS) for 1:12,000-scale products. Aerial cameras have current certification from the USGS, National Mapping Division, Optical Science Laboratory. Test calibration scans are performed on all source photography scanners. Horizontal positional accuracy is determined by the Orthophoto Accuracy (ORACC) software program for DOQQ data produced by the National Mapping Division. The program determines the accuracy by finding the line and sample coordinates of the passpoints in the DOQQ and fitting these to their ground coordinates to develop a root mean square error (RMSE). From 4 to 9 points are checked. As a further accuracy test, the image line and sample coordinates of the DEM corners are transformed and compared with the actual X,Y DEM corner values to determine if they are within the RMSE. Additional information on this testing procedure can be found in U.S. Department of the Interior, U.S. Geological Survey, 1993, Technical Instructions, ORACC Users Manual (draft): Reston, VA. Adjacent DOQQ's, when displayed together in a common planimetric coordinate system, may exhibit slight positional discrepancies across common DOQQ boundaries. Linear features, such as streets, may not be continuous. These edge mismatches, however, still conform to positional horizontal accuracy within the NMAS. Field investigations to validate DOQQcositional accuracy reliabilty are periodically conducted by the USGS, National Mapping Division, Geometronics Standards Section. DOQQ's produced approved RMSE test procedures. In processing this data the Bureua of Reclamation's GIS and Remote Sensing Group did not alter the positional accuracy.

Lineage:

Process_Step:

Process_Description:

The production procedures, instrumentation, hardware and software used in the collection of standard USGS DOQQ's vary depending on systems used at the contract, cooperator or USGS production sites. The majority of DOQQ datasets are acquired through government contract. The process step describes, in general, the process used in the production of standard USGS DOQ data sets. 1. The rectification process requires, as input, a user parameter file to control the rectification process, a digital elevation model (DEM1) gridded to user specified bounds, projection, zone, datum and X-Y units, a scanned digital image file (PHOTO1) covering the same area as the DEM, ground X-Y-Z point values (CONTROL_INPUT) and their conjugate photo coordinates in the camera coordinate system, and measurements of the fiducial marks (CAMERA_INPUT) in the digitized image. The camera calibration report (CAMERA_INPUT) provides the focal length of the camera and the distances in millimeters from the camera's optical center to the camera's 8 fiducial marks. These marks define the frame of reference for spatial measurements made from the photograph. 2. Ground control points (CONTROL_INPUT) acquired from ground surveys or developed in aerotriangulation, are third order class 1 or better, and meet National Map Accuracy Standard (NMAS) for 1:12,000-scale. Ground control points are in the Universal Transverse Mercator or the State Plane Coordinate System on NAD83. Horizontal and vertical residuals of aerotriangulated tie-points are equal to or less than 2.5 meters. Standard aerotriangulation passpoint configuration consists of 9 ground control points, one near each corner, one at the center near each side and 1 near the center of the photograph, are used. The conjugate positions of the ground control points on the photograph are measured and recorded in camera coordinates. 3. The raster image file (PHOTO_1) is created by scanning an aerial photograph film diapositive with a precision image scanner. An aperture of approximately 25 to 32 microns is used, with an aperture no greater than 32 microns permitted. Using 1:40,000-scale photographs, a 25-micron scan aperture equates to a ground resolution of 1-meter. The scanner converts the photographic image densities to gray scale values ranging from 0 to 255 for black and white photographs. Scan files with ground resolution less than 1 meter or greater than 1 meter but less than 1.28 meters are resampled to 1 meter. 4. The principal elevation data source (DEM1) are standard DEM datasets from the National Digital Cartographic Data Base (NDCDB). DEM's that meet USGS standards are also produced by contractors to fulfill DOQQ production requirements and are subsequently archived in the NDCDB. All DEM data is equivalent to or better than USGS DEM standard level 1. The DEM used in the production of DOQQ's generally has a 30-meter grid post spacing and possesses a vertical RMSE of 7-meters or less. A DEM covering the extent of the photograph is used for the rectification. The DEM is traversed from user-selected minimum to maximum X-Y values and coordinates in the digitized photograph using transformations mentioned above. For each raster image cell subdivision, a brightness or gray-scale value is obtained using nearest neighbor, bilinear, or cubic convolution resampling of the scanned image. The pixel processing algorithm is indicated in the header file . An inverse transformation relates the image coordinates referenced to the fiducial coordinate space back to scanner coordinate space. For those areas for which a 7.5-minute DEM is unavailable and relief differences are less than 150 feet, a planar-DEM (slope-plane substitute grid) may be used. 5. Rectification Process: The photo control points and focal length are iteratively fitted to their conjugate ground control points using a single photo space resection equation. From this mathematical fit is obtained a rotation matrix of constants about the three axes of the camera. This rotation matrix can then be used to find the photograph or camera coordinates of any other ground X-Y-Z point. Next a two dimensional fit is made between the measured fiducial marks on thedigitized photograph and their conjugate camera coordinates. Transformation constants are developed from the fit and the camera or photo coordinates are used in reverse to find their conjugate pixel coordiates on the digitized photograph. 6. Quality Control: All data is inspected according to a quality control plan. DOQ contractors must meet DOQQ standards for attribute accuracy, logical consistency, data completeness and horizontal positional accuracy. During the initial production phase, all rectification inputs and DOQQ data sets are inspected for conformance to standards. 7. After a production source demonstrates high quality, inspections will be made to 10% of delivery lots (40 DOQs per lot).All DOQ's are visually inspected for gross positional errors and tested for physical format standards.

Process_Date: Unknown

Process_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Person: David Salas

Contact_Organization: U.S. Bureau of Reclamation

Contact_Position: Project Manager

Contact_Address:

Address_Type: Mailing Address

Address: P.O. Box 25007

City: Denver

State_or_Province: Colorado

Postal_Code: 80225

Country: USA

Contact_Voice_Telephone: 303-445-3619

Contact_Electronic_Mail_Address: desalas@do.usbr.gov

Spatial_Data_Organization_Information:

Direct_Spatial_Reference_Method: Raster

Raster_Object_Information:

Raster_Object_Type: Pixel

Row_Count: 6016

Column_Count: 4675

Vertical_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: 13

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: 0.9996

Longitude_of_Central_Meridian: -105

Latitude_of_Projection_Origin: 0

False_Easting: 500000

False_Northing: 0

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: Coordinate Pair

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

Semi-major_Axis: 6378137

Denominator_of_Flattening_Ratio: 298.257222

Entity_and_Attribute_Information:

Overview_Description:

Entity_and_Attribute_Overview:

For DOQQ's from panchromatic source each pixel contains an 8-bit gray-scale value between 0-255. A value of 0 representsr black while a value of 255 represents white. Values between 0 and 255 are repesented as a shade of gray. Areas where the rectification process is incomplete due to incomplete data (i.e., lack of elevation data, gaps), are represented with the numeric value of 0.

Entity_and_Attribute_Detail_Citation:

U.S. Department of the Interior, U.S. Geological Survey, 1992, Standards for digital orthophotos: Reston, VA. A hypertext version is available at: <URL:http://rockyweb.cr.usgs.gov/nmpstds/doqstds.html>

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: USGS/CSS/Core Science Analytics and Synthesis

Contact_Person: USGS-NPS Vegetation Mapping Program Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: Denver Federal Center, Building 810, Room 8000, MS 302

City: Denver

State_or_Province: Colorado

Postal_Code: 80225

Contact_Voice_Telephone: (303) 202-4220

Contact_Facsimile_Telephone: 303-202-4219

Contact_Electronic_Mail_Address: gs-b-npsveg@usgs.gov

Resource_Description:

Downloadable Data.

Distribution_Liability:

The U.S. Geological Survey and the National Park Service shall not be held liable for improper or incorrect use of the data described and/or contained herein. These data and related graphics (if available) are not legal documents and are not intended to be used as such.

The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular. Any related graphics (if available) are intended to aid the data user in acquiring relevant data; it is not approriate to use the related graphics as data.

The U.S. Geological Survey and the National Park Service gives no warranty, expressed or implied, as to the accuracy, reliability, or completeness of these data. It is strongly recommended that these data are directly acquired from an U.S. Geological Survey and National Park Service servers and not indirectly through other sources which may have changed the data in some way. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the utility of the data on another system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. Mention of trade names or commercial products in this metadata report does not constitute endorsement or recommendation for use by the U. S. Department of the Interior, U. S. Geological Survey and National Park Service.

Standard_Order_Process:

Digital_Form:

Digital_Transfer_Information:

Format_Name: HTML

Digital_Transfer_Option:

Online_Option:

Computer_Contact_Information:

Network_Address:

Network_Resource_Name: <http://biology.usgs.gov/npsveg/fous/index.html>

Access_Instructions: Internet Access

Fees: None

Metadata_Reference_Information:

Metadata_Date: 20021205

Metadata_Review_Date: 20100524

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: USGS/CSS/Core Science Analytics and Synthesis

Contact_Person: USGS-NPS Vegetation Mapping Program Coordinator

Contact_Address:

Address_Type: mailing and physical address

Address: Denver Federal Center, Building 810, Room 8000, MS 302

City: Denver

State_or_Province: Colorado

Postal_Code: 80225

Contact_Voice_Telephone: (303) 202-4220

Contact_Facsimile_Telephone: 303-202-4219

Contact_Electronic_Mail_Address: gs-b-npsveg@usgs.gov

Metadata_Standard_Name:

FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata

Metadata_Standard_Version: FGDC-STD-001.1-1999

Metadata_Extensions:

Online_Linkage:

<http://www.nbii.gov/portal/server.pt/community/fgdc_metadata/255>