Georgia GIS Data Clearinghouse
Metadata for Digital Raster Graphic
Table of Contents
-Citation-
8.1 ORIGINATOR: USGS
8.2 PUBLICATION DATE: 19960917
8.4 TITLE: Georgia DRG
8.6 GEOSPATIAL DATA PRESENTATION FORM: "map"
-Publication Information-
8.8.1 PUBLICATION PLACE: Reston, VA
8.8.2 PUBLISHER: USGS
-Description-
1.2.1 ABSTRACT: The Digital Raster Graphic (DRG) is a raster image of a
scanned USGS topographic map including the collar information,
georeferenced to the UTM grid.
1.2.2 PURPOSE: A DRG is useful as a source or background layer in a GIS,
as a means to perform quality assurance on other digital products,
and as a source for the collection and revision of DLG data. DRG's
can also be merged with other digital data, e.g. DEM's or DOQ's, to
produce a hybrid digital file.
1.2.3 SUPPLEMENTAL INFORMATION: 746533.13006588, 3572061.36143461
-Time period of content-
Single Date/Time
9.1.1 CALENDAR DATE: 19960917
1.3.1 CURRENTNESS REFERENCE: "Ground Condition"
-Status-
1.4.1 PROGRESS: "Complete"
1.4.2 MAINTENANCE AND UPDATE FREQUENCY: "Irregular"
-Spatial Domain-
Bounding Coordinates
1.5.1.1 WEST BOUNDING COORDINATE:
1.5.1.2 EAST BOUNDING COORDINATE:
1.5.1.3 NORTH BOUNDING COORDINATE:
1.5.1.4 SOUTH BOUNDING COORDINATE:
-Keywords-
Theme
1.6.1.1 THEME KEYWORD THESAURUS: "None"
1.6.1.2 THEME KEYWORD: digital raster graphic
1.6.1.2 THEME KEYWORD: DRG
1.6.1.2 THEME KEYWORD: topographic map
Place
1.6.2.1 PLACE KEYWORD THESAURUS: Department of Commerce, 1977, Countries,
Dependencies, Areas of Special Sovereignty, and their Principal
Administrative Divisions (Federal Information Processing Standard
10-3): Washington, Department of Commerce, National Institute of
Standards and Technology.
1.6.2.2 PLACE KEYWORD: US
1.6.2.1 PLACE KEYWORD THESAURUS: Department of Commerce, 1987, Codes for
the Identification of the States, The District of Columbia and the
Outlying Areas Of The United States, and Associated Areas (Federal
Information Processing Standard 5-2): Washington, Department of
Commerce, National Institute of Standards and Technology.
1.6.2.2 PLACE KEYWORD: GA
1.6.2.2 PLACE KEYWORD:
1.6.2.2 PLACE KEYWORD:
1.6.2.2 PLACE KEYWORD:
1.7 ACCESS CONSTRAINTS: "None"
1.8 USE CONSTRAINTS: Acknowledgment of the USGS would be appreciated in
products derived from these data.
1.11 DATA SET CREDIT: This DRG was produced through an Innovative
Partnership agreement between The Land Information Technology
Company, Ltd., of Aurora, CO and the USGS.
-Attribute Accuracy-
2.1 ATTRIBUTE ACCURACY REPORT: The DRG is an 8-bit color image that employs
a color palette to ensure uniform colors throughout a particular DRG
series. All DRG's within a series must have the same RGB value.
2.2 LOGICAL CONSISTENCY REPORT: Not Applicable
2.3 COMPLETENESS REPORT: The DRG is a faithfully reproduced digital image of
the original source map. Some differences may be detected between the
source graphic used and the DRG due to the RGB values assigned that
particular color. The intent is to recreate those colors as near as
possible. Data completeness for DRG files reflect content of the source
graphic. Features may have been eliminated or generalized on the source
graphic due to scale and legibility constraints. For information on
collection and inclusion criteria, see U.S. Geological Survey, 1994,
Standards for 1:24,000-Scale Digital Line Graphs and Quadrangle Maps:
National Mapping Program Technical Instructions and U.S. Geological
Survey, 1994, Standards for Digital Line Graphs: National Mapping Program
Technical Instructions.
-Positional Accuracy-
Horizontal Positional Accuracy
2.4.1.1 HORIZONTAL POSITIONAL ACCURACY REPORT: While the datum of the
published map is retained to be consistent with other USGS digital
data, this image is cast on the UTM and may be INCONSISTENT with the
credit note on the image collar.
Vertical Positional Accuracy
2.4.2.2 VERTICAL POSITIONAL ACCURACY REPORT: Refer to the DRG collar for
information about vertical positional accuracy.
-Lineage-
Source Information
Source Citation
2.5.1.5 SOURCE CITATION ABBREVIATION: map1
8.1 ORIGINATOR: USGS
8.2 PUBLICATION DATE: 1981
8.4 TITLE: [DOQQ within the state of Georgia]
8.6 GEOSPATIAL DATA PRESENTATION FORM: "map"
--Publication Information--
8.8.1 PUBLICATION PLACE: Reston, VA
8.8.2 PUBLISHER: USGS
2.5.1.2 SOURCE SCALE DENOMINATOR: 24000
2.5.1.3 TYPE OF SOURCE MEDIA: "paper"
-Source Time Period of Content-
Single Date/Time
9.1.1 CALENDAR_DATE: 1981
2.5.1.4.1 SOURCE CURRENTNESS REFERENCE: "ground condition"
2.5.1.6 SOURCE CONTRIBUTION: The source map is scanned to produce the DRG.
-Process Step-
2.5.2.1 PROCESS DESCRIPTION: The production procedures, instrumentation,
hardware, and software used in the collection of standard DRG
products vary depending on systems used at the contract, cooperator
or USGS production sites. The majority of DRG data sets are
acquired through government contract. The process step describes,
in general, the process used in the production of standard DRG data
sets.
1. Production of a DRG begins with the scanning of a paper
7.5-minute topographic map (map1) on a high-resolution scanner.
Scanning resolutions range from 500 - 1000 dpi with the output file
running between 160-300 mb.
2. Removal of screens (descreening) and color quantization to reduce
the number of colors also takes place during the scanning phase.
3. The raw scan file is then transformed and georeferenced using UTM
coordinates of the sixteen 2.5-minute grid ticks, which are obtained
using the in-house produced program COORDAT and stored in a ground
control file. Those sixteen 2.5-minute ticks are interactively
visited and assigned their respective UTM coordinates. USGS program
XSHAPES4 then performs a piecewise linear rubber sheet
transformation.
4. An output resolution of 2.4 meters (8.2 feet) is chosen in order
to resample the file to 250 dpi.
5. The image file is converted to a TIFF and further reduced by
converting the file to a run length encoding Packbits
compression(type 32773).
6. The color palette of the compressed DRG is then standardized by
replacing the original RGB values assigned during the scanning
process with standard RGB value combinations using the in-house
produced TIFFREMAP program.
7. Prior to archiving the DRG undergoes the following quality
assurance procedures:
a. The color index values of each DRG are checked to ensure
the RGB combinations are consistent with the standardized
color palette.
b. All DRG files are inspected to ensure that they are
geometrically consistent with normal map presentation.
c. Selected DRG's are checked to ensure that data elements in
the DRG metadata file correspond to the map collar information
and to the information in the associated image file.
d. Selected DRG's are checked for georeferencing accuracy by
comparing the book value of latitude and longitude tick marks
with corresponding tick intersections in the DRG image.
e. Transformations are checked on selected DRG's by comparing
the positions of well defined points, such as UTM grid
intersections in the graphic product, with the corresponding
image points in the DRG.
USGS DRG production specifications are available on request from
the National Mapping Division and Mid-Continent Mapping Center by
contacting:
Rolla-ESIC
U.S. Geological Survey
1400 Independence Rd., MS231
Rolla, MO 65401-2602
Phone (314)341-0851
Facsimile (314)341-9375
E-mail to esic@mcdgs91.cr.usgs.gov
World Wide Web: http://mcmcweb.cr.usgs.gov/gdc/
2.5.2.2 SOURCE USED CITATION ABBREVIATION: map1
2.5.2.3 PROCESS DATE: 19960917
3.2 DIRECT SPATIAL REFERENCE METHOD: "Raster"
-Raster Object Information-
3.4.1 RASTER OBJECT TYPE: "Pixel"
3.4.2 ROW COUNT: 6825
3.4.3 COLUMN COUNT: 5627
-Horizontal Coordinate System Definition-
Planar
4.1.2.2.1 GRID COORDINATE SYSTEM NAME: "Universal Transverse Mercator"
Universal Transverse Mercator (UTM)
4.1.2.2.2.1 UTM ZONE NUMBER: 16 or 17
Transverse Mercator
4.1.2.1.2.17 SCALE FACTOR AT CENTRAL MERIDIAN: 0.9996
4.1.2.1.2.2 LONGITUDE AT CENTRAL MERIDIAN: -87.000
4.1.2.1.2.3 LATITUDE OF PROJECTION ORIGIN: 0.0
4.1.2.1.2.4 FALSE EASTING: 500000.
4.1.2.1.2.5 FALSE NORTHING: 0.0
--Planar Coordinate Information--
4.1.2.4.1 PLANAR COORDINATE ENCODING METHOD: "row and column"
-Coordinate Representation-
4.1.2.4.2.1 ABSCISSA RESOLUTION: 2.43840000
4.1.2.4.2.2 ORDINATE RESOLUTION: -2.43840000
4.1.2.4.4 PLANAR DISTANCE UNITS: "meters"
-Geodetic Model-
4.1.4.1 HORIZONTAL DATUM NAME: North American Datum 1927
4.1.4.2 ELLIPSOID NAME: Clarke 1866
4.1.4.3 SEMI-MAJOR AXIS: 6378206.4
4.1.4.4 DENOMINATOR OF FLATTENING RATIO: 294.98
-Overview Description-
5.2.1 Each raster entity or pixel contains a color index from 0 through 12
referencing a color palette of RGB values from 0 through 255 in
which the standard colors used in the DRG are defined.
USGS DRG Color Palette
Digital Number Color Red Green Blue
0 Black 0 0 0
1 White 255 255 255
2 Blue 0 151 164
3 Red 203 0 23
4 Brown 131 66 37
5 Green 201 234 157
6 Purple 137 51 128
7 Yellow 255 234 0
8 Light Blue 167 226 226
9 Light Red 255 184 184
10 Light Purple 218 179 214
11 Light Grey 209 209 209
12 Light Brown 207 164 142
5.2.2 ENTITY AND ATTRIBUTE DETAIL CITATION: Draft Standards for Digital
Raster Graphic.
-Distributor-
Contact Organization Primary
10.1.2 CONTACT ORGANIZATION: Earth Science Information Center, U.S.
Geological Survey Contact Address
10.4.1 ADDRESS TYPE: "mailing address"
10.4.2 ADDRESS: 507 National Center
10.4.3 CITY: Reston
10.4.4 STATE OR PROVINCE: Virginia
10.4.5 POSTAL CODE: 22092
10.5 CONTACT VOICE TELEPHONE: 1 800 USA MAPS
10.5 CONTACT VOICE TELEPHONE: 1 703 648 6045
6.3 DISTRIBUTION LIABILITY: Although these data have been processed
successfully on a computer system at the USGS, no warranty expressed
or implied is made by the USGS regarding the use of the data on any
other system, nor does the act of distribution constitute any such
warranty. The USGS will warrant the delivery of this product in
computer-readable format and will offer appropriate adjustment of
credit when the product is determined unreadable by correctly
adjusted computer input peripherals, or when the physical medium is
delivered in damaged condition. Requests for adjustment of credit
must be made within 90 days from the date of this shipment from the
ordering site.
-Standard Order Process-
Digital Form
Digital Transfer Information
6.4.2.1.1 FORMAT NAME: TIFF
6.4.2.1.2 FORMAT VERSION NUMBER: 6.0
6.4.2.1.6 FILE DECOMPRESSION TECHNIQUE: Packbits
Digital Transfer Option
Offline Options
6.4.2.2.2.1 OFFLINE MEDIA: "CD-ROM"
6.4.2.2.2.3 RECORDING FORMAT: "ISO 9660"; DRG image files with
corresponding metadata files.
6.4.3 FEES: For delivery on CD-ROM, the charge is $32 per CD-ROM
7.1 METADATA DATE: 19960917
Metadata Contact
Contact Organization Primary
10.1.2 CONTACT ORGANIZATION: U.S. Geological Survey
Contact Address
10.4.1 ADDRESS TYPE: "mailing address"
10.4.2 ADDRESS: 590 National Center
10.4.3 CITY: Reston
10.4.4 STATE OR PROVINCE: Virginia
10.4.5 POSTAL CODE: 22092
10.5 CONTACT VOICE TELEPHONE: 1 703 648 4533
10.8 CONTACT ELECTRONIC MAIL ADDRESS: Copies of this publication are
available from anonymous File Transfer Protocol (anonymous FTP);
ftp://fgdc.er.usgs.gov/
7.5 METADATA STANDARD NAME: "Content Standards for Digital Geospatial
Metadata"
7.6 METADATA STANDARD VERSION: 19940608