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Table of Contents
IDENTIFICATION_INFORMATION
DATA_QUALITY_INFORMATION
SPATIAL_DATA_ORGANIZATION_INFORMATION
SPATIAL_REFERENCE_INFORMATION
ENTITY_AND_ATTRIBUTE_INFORMATION
DISTRIBUTION_INFORMATION
IDENTIFICATION_INFORMATION
Citation:
Citation_Information:
Originator:
Publication_Date: 2002/05/28
Title:
Edition: Second Generation National
Digital Ortho Photography
Geospatial_Data_Presentation_Form: Raster
Publication_Information:
Publication_Place:
Publisher:
Other_Citation_Details:
Online_Linkage:
http://www.cast.uark.edu/cast/geostor/
Larger_Work_Citation:
Citation_Information:
Originator:
Conservation Service; Farm Service
Agency;
Publication_Date: 1990
Title: National Digital Ortho Program
Publication_Information:
Publication_Place:
Publisher:
Online_Linkage:
http://edcwww.cr.usgs.gov/webglis/
Description:
Abstract:
Orthophotos combine the image characteristics of a photograph with
the geometric qualities of a map. The primary digital orthophoto quadrangle
(DOQ) 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 the DOQ is equivalent to a quarter-quadrangle plus the
overedge ranges from a minimum of 50 meters to a maximum of 300 meters beyond
the extremes of the primary and secondary corner points. The overedge is
included to facilitate tonal matching for mosaicking and for the placement of
the NAD83 and secondary datum corner ticks. The normal orientation of data is
by lines (rows) and samples (columns). Each line contains a series of pixels
ordered from west to east with the order of the lines from north to south. This
series of DOQs was produced as a part of the Arkansas Digital Orthophotography
Program headed by the Arkansas State Land Information Board and the Arkansas
Geographic Information Office. The aerial photography used to create the
digital images was flown between January 15th and March 31st during
2000-2002. The images make use of three separate spectral bands to form a color
infrared composite, which allows easier analysis of agriculture, land use,
vegetation, and other features with infrared reflectance. Areas of high vegetative
vigor appear bright red in color infrared imagery.
Purpose:
DOQs serve a variety of purposes, from interim maps to field
references for Earth science investigations and analysis. The DOQ is useful as
a layer of a geographic information system and as a tool for revision of
digital line graphs and topographic maps. It is the intention of the Arkansas
State Land Information board to facilitate the dissemination of public data.
Supplemental_Information:
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 200001
Ending_Date: 200204
Currentness_Reference:
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -94.6333
East_Bounding_Coordinate: -89.5987
North_Bounding_Coordinate: 36.5235
South_Bounding_Coordinate: 32.9574
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: DOQ, DOQQ, Digital, Ortho, Quadrangles, ADOP,
Aerial, Photography, Rectified Image, Orthophoto, quarter quadrangle,
Place:
Place_Keyword_Thesaurus: None
Place_Keyword:
Access_Constraints:
None
Use_Constraints:
Acknowledgement of the Arkansas State Land Information Board would
be appreciated in products derived from this data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Contact_Person: Shelby Johnson
Contact_Position:
Contact_Address:
Address_Type: mailing
Address:
City:
State_or_Province:
Postal_Code: 72201
Country:
Contact_Voice_Telephone: 501-682-2767
Contact_Facsimile_Telephone: 501-682-2040
Contact_Electronic_Mail_Address:
shelby.johnson@mail.state.ar.us
Hours_of_Service: Monday - Friday
Native_Data_Set_Environment:
PCI Ortho Engine 8x
Tiff /TFW
DATA_QUALITY_INFORMATION
Attribute_Accuracy:
Attribute_Accuracy_Report:
During photographic reproduction of the source photography,
limited analog dodging is performed to improve image quality. Analog dodging
consists of holding back light from certain areas of the sensitized
photographic material to avoid overexposure. 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, rectification, and mosaicking 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. Slight systematic radiometric differences can
be detected between adjacent DOQ 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 DOQ file coverages.
Logical_Consistency_Report:
All DOQ image file sizes are validated by
visual inspection.
Completeness_Report:
All DOQ imagery is visually inspected for completeness to ensure
that no gaps or image misplacements exist in the image area or in overedge
coverage. DOQ images may be derived by mosaicking multiple images, in order to
insure complete coverage. All DOQs are cloud free within the image area. Some
clouds may, very infrequently, be encountered only in the overedge coverage.
Source photography is leaf-off.
Positional_Accuracy:
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The DOQ horizontal positional
accuracy and the assurance of that accuracy depend, in part, on the accuracy of
the data inputs to the rectification process. These inputs consist of the
digital elevation model (DEM), aero-triangulation control and methods, 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. Planimetric
control is measured and analyzed to produce residuals of less than 2.5 meters. The controls are 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, and
Optical Science Laboratory. Test calibration scans are performed on all source
photography scanners. Horizontal positional accuracy
is determined by the PixMap software programs Main_BC and RectifyQC for DOQ
data produced by Pixxures. The programs determines the accuracy by finding
sample coordinates of control points in the DOQ and fitting these to their
ground coordinates in base or control imagery to develop a root mean square
error (RMSE). From 4 to 9 points are checked. Adjacent DOQs, when
displayed together in a common planimetric coordinate system, may exhibit
slight positional discrepancies across common DOQ 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 DOQ positional accuracy
reliability are periodically conducted by the Arkansas Geographic Information
Office, following the National Standard for Spatial Data Accuracy (Part 3)
testing methodologies.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Not Applicable
Source_Information:
Source_Citation:
Citation_Information:
Originator:
Publication_Date:
1999
Title: National
Elevation Dataset
Edition: 1
Geospatial_Data_Presentation_Form: raster digital data
Publication_Information:
Publication_Place:
Publisher:
Other_Citation_Details:
Online_Linkage:
<http://gisdata.usgs.net/ned/default.htm>
Larger_Work_Citation:
Citation_Information:
Originator:
Publication_Date:
Title:
Publication_Information:
Publication_Place:
Publisher:
Online_Linkage:
Source_Scale_Denominator:
Type_of_Source_Media: cartridge tape
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19990201
Ending_Date:
unknown
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: DEM 1
Source_Contribution:
Elevation data in the form of an
ortho-DEM regridded to
user-specified intervals and
bounds.
Alternate Source_Information:
Source_Citation:
Citation_Information:
Originator:
Publication_Date: 1988
Title: Digital Elevation Model
Edition: DEM 1
Geospatial_Data_Presentation_Form:
map
Publication_Information:
Publication_Place:
Publisher:
Other_Citation_Details:
Online_Linkage:
Larger_Work_Citation:
Citation_Information:
Originator:
Publication_Date:
Title:
Publication_Information:
Publication_Place:
Publisher:
Online_Linkage:
Source_Scale_Denominator:
Type_of_Source_Media: cartridge tape
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 1988
Ending_Date: present
Source_Currentness_Reference: ground
conditions
Source_Citation_Abbreviation: DEM 1
Source_Contribution:
Elevation data in the form of an
ortho-DEM regridded to
user-specified intervals and bounds.
Process_Step:
Process_Description:
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.
Ground control points (CONTROL_INPUT) acquired from base imagery
or existing orthophotos 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.
The overlap area between every other image in a 60%
forward overlap is populated with tie/pass points and ground control points.
The conjugate positions of the ground control points on the
photograph are measured and recorded in camera coordinates. Aerotriangulation tie/pass point and control point
configuration consists of 6 tie/pass points in each 2-way overlap between
adjacent frames, both forward and side.
In a 4-way overlap one control point (CONTROL_INPUT) is used in
conjunction with 6 tie/pass points.
A quaternion based iterative analytical adjustment
calculates XYZ and Omega, Phi, and Kappa values for each frame. Self-calibrating the camera internal
geometries build a camera model (CAMERA_INPUT) to support rectification. Horizontal and vertical residuals
of aerotriangulated tie-points are equal to or less than 2.5 meters.
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.
The principal elevation data sources (DEM1) are standard DEM
datasets from the National Digital Cartographic Data Base (NDCDB). DEMs that
meet USGS standards are also produced by contractors to fulfill DOQ 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
DOQs 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 the DEM X-Y-Z values are used to find pixel 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.
Source_Used_Citation_Abbreviation: PixMap
Process_Date: 20020528
Source_Produced_Citation_Abbreviation:
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Organization: Pixxures,
Inc.
Contact_Person: Kathy St. Amand
Contact_Position: Pixxures Project
Manager
Contact_Address:
Address_Type: mailing and physical
address
Address:
City:
State_or_Province:
Postal_Code: 80007
Country:
Contact_Voice_Telephone: (303)
302-8563
Contact_Facsimile_Telephone:
Contact_Electronic_Mail_Address:
kstamand@Pixxures.com
Hours_of_Service: Monday- Friday
SPATIAL_DATA_ORGANIZATION_INFORMATION
Direct_Spatial_Reference_Method: Raster
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type:
Point_and_Vector_Object_Count:
SPATIAL_REFERENCE_INFORMATION
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: Universal
Transverse Mercator
Universal_Transverse_Mercator:
UTM_Zone_Number: 15
Transverse_Mercator:
Scale_Factor_at_Central_Meridian:
0.999600
Longitude_of_Central_Meridian:
-93.000000
Latitude_of_Projection_Origin:
0.000000
False_Easting: 500000.000000
False_Northing: 0.000000
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: GRS 80
Semi-major_Axis: 6378137.0000000
Denominator_of_Flattening_Ratio: 298.26
ENTITY_AND_ATTRIBUTE_INFORMATION
Overview_Description:
Entity_and_Attribute_Overview:
Each DOQ is made up of three separate spectral bands. Each pixel in each spectral band is assigned
a digital number from 0 to 255, indicating the amount of reflectance (within
the desired spectrum) of the corresponding ground location. Each of the three
bands contributes a part of the RGB value for pixel display, with band 1
(near-infrared) representing the red value, band 2 (red) representing the green
value, and band 3 (green) representing the blue value. Each band can be viewed
separately as a greyscale image.
DISTRIBUTION_INFORMATION
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Contact_Person: Shelby Johnson
Contact_Position:
Contact_Address:
Address_Type: Mailing address
Address:
City:
State_or_Province:
Postal_Code: 72201
Country:
Contact_Voice_Telephone: 501-682-2767
Contact_Facsimile_Telephone: 501-682-2040
Contact_Electronic_Mail_Address:
shelby.johnson@mail.state.ar.us
Hours_of_Service: Monday - Friday
Resource_Description:
Distribution_Liability:
The data herein, including but not limited to geographic data,
tabular data, analytical data, electronic data structures or files, are
provided "as is" without warranty of any kind, either expressed or
implied, or statutory, including, but not limited to, the implied warranties or
merchantability and fitness for a particular purpose. The entire risk as to the
quality and performance of the data is assumed by the user. No guarantee of
accuracy is granted, nor is any responsibility for reliance thereon assumed. In no event shall the
Arkansas State Land Information Board be liable for direct, indirect,
incidental, consequential or special damages of any kind, including, but not
limited to, loss of anticipated profits or benefits arising out of use of or
reliance on the data. The Arkansas State Land Information Board does not accept
liability for any damages or misrepresentation caused by inaccuracies in the
data or as a result of changes to the data caused by system transfers or other
transformations or conversions, nor is there responsibility assumed to maintain
the data in any manner or form. These data have been developed from the best
available sources. Although efforts have been made to ensure that the data are
accurate and reliable, errors and variable conditions originating from physical
sources used to develop the data may be reflected in the data supplied. Users
must be aware of these conditions and bear responsibility for the appropriate
use of the information with respect to possible errors, scale, resolution,
rectification, positional accuracy, development methodology, time period,
environmental and climatic conditions and other circumstances specific to these
data. The user is responsible for understanding the accuracy limitations of the
data provided herein. The burden for determining fitness for use lies entirely
with the user. The user should refer to the accompanying metadata notes for a
description of the data and data development procedures. Although these data
have been processed successfully on computers at the Arkansas Geographic
Information Office, no guarantee, expressed or implied, is made by Arkansas
State Land Information Board regarding the use of these data on any other
system, nor does the act of distribution constitute or imply any such warranty.
Distribution of these data is intended for information purposes and should not
be considered authoritative for engineering, legal and other site-specific
uses.
Custom_Order_Process:
ADOP data may be searched, and retrieved in a number of user
defined projections through GeoStor http://www.cast.uark.edu/cast/geostor/
There is no fee associated with acquiring ADOP data from GeoStor.
METADATA_REFERENCE_INFORMATION
Metadata_Date: 20020528
Metadata_Review_Date: 20020528
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Contact_Person: Learon Dalby
Contact_Position: GIS Program Manager
Contact_Address:
Address_Type: Mailing address
Address:
City:
State_or_Province:
Postal_Code: 72001
Country:
Contact_Voice_Telephone: 501-682-2929
Contact_Facsimile_Telephone: 501-682-
4020
Contact_Electronic_Mail_Address:
learon.dalby@mail.state.ar.us
Hours_of_Service: Monday - Friday
Metadata_Standard_Name: FGDC CSDGM
Metadata_Standard_Version: FGDC-STD-001-1998