National Spatial Data Infrastructure
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National Spatial Data Infrastructure
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USGS Geospatial Data Clearinghouse
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A Digital Raster Graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. This is a data-set level implementation of the Federal Geographic Data Committee's Content Standards for Digital Geospatial Metadata.
Information about prepackaged CD DRG records can be obtained from the EROS Data Center.
Identification_Information:
Citation:
Citation_Information:
Originator:
U.S. Geological Survey
EROS Data Center
Publication_Date: 1996
Title: Digital Raster Graphics (DRGs)
Edition: 1.0
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Digital Raster Graphics
Issue_Identification:
Digital Raster Graphics (DRGs) are scanned color images of USGS
topographic maps.
Publication_Information:
Publication_Place: Sioux Falls
Publisher:
U.S. Geological Survey
EROS Data Center
Other_Citation_Details:
Earth Science Information Centers (ESIC) offer nationwide information
and sales service for USGS map products and earth science publications.
For additional information, contact any USGS Earth Science Information
Center (ESIC), or call 1-888-ASK-USGS.
Online_Linkage: http://edc.usgs.gov/
Description:
Abstract:
A digital raster graphic (DRG) is a scanned image of a U.S. Geological
Survey (USGS) topographic map. The scanned image includes all map
collar information. The image inside the map neatline is georeferenced
to the surface of the Earth. The DRG can be used to collect, review,
and revise other digital data, especially digital line graphs (DLG).
When the DRG is combined with other digital products, such as digital
orthophoto quadrangles (DOQ) or digital elevation models (DEM), the
resulting image provides additional visual information for the extract-
ion and revision of base cartographic information. The USGS is producing
DRG's of the 1:24,000-,1:24,000/1:25,000-, 1:63,360- (Alaska), 1:100,000-,
and 1:250,000-scale topographic map series.
Purpose:
The DRG is used for validating digital line graphs (DLG's) and for
DLG data collection and revision. The DRG can help assess the
completeness of digital data from other mapping agencies. It can also
be used to produce "hybrid" products. These include combined DRG's
and DOQ's for revising and collecting digital data, DRG's and
DEM's for creating shaded-relief DRG's, and combinations of DRG, DOQ,
and DLG data. Although a standard DRG is an effective mapping tool,
its full potential for digital production is realized in combination
with other digital data
Supplemental_Information:
Digital raster graphic (DRG) data on CD-ROM are being produced
by the U.S. Geological Survey (USGS) through an Innovative Partnership
agreement with The Land Information Technology Company, Ltd., of
Aurora, CO. This series includes DRG's of USGS standard series
quadrangle maps of the United States, its Trusts, and Territories.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 1996
Ending_Date: Present
Currentness_Reference: ground condition
Status:
Progress: In work
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -124.7333
East_Bounding_Coordinate: -067.9500
North_Bounding_Coordinate: 49.3833
South_Bounding_Coordinate: 24.5333
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: digital elevation model
Theme_Keyword: DEM
Theme_Keyword: digital terrain model
Theme_Keyword: contour line
Theme_Keyword: digital contours
Theme_Keyword: DOQ
Theme_Keyword: digital orthophoto
Theme_Keyword: digital orthophotoquad
Theme_Keyword: digital image map
Theme_Keyword: aerial photograph
Theme_Keyword: paper map
Theme_Keyword: map
Theme_Keyword: digital line graph
Theme_Keyword: U.S. Public Land Survey System
Theme_Keyword: hydrography
Theme_Keyword: transportation
Theme_Keyword: hydrography
Theme_Keyword: topographic
Theme_Keyword: Universal Transverse Mercator (UTM)
Theme_Keyword: scanner
Theme_Keyword: raster
Theme_Keyword: digital image
Place:
Place_Keyword_Thesaurus:
U.S. Department of Commerce, 1977, Countries, dependencies, areas of
special sovereignty, and their principal administrative divisions
(Federal Information Processing Standard 10-3):Washington, D.C.,
National Institute of Standards and Technology.
Place_Keyword: US
Place_Keyword: United States
Place_Keyword: FIPS codes for states covered
Place_Keyword: Puerto Rico
Temporal:
Temporal_Keyword_Thesaurus: None
Temporal_Keyword: true ground conditions
Access_Constraints: None
Use_Constraints:
Acknowledgement of the U.S. Geological Survey would be appreciated
n products derived from these data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
U.S. Geological Survey
EROS Data Center
Contact_Position: Customer Services Representative
Contact_Address:
Address_Type: mailing and physical address
Address:
U.S. Geological Survey
EROS Data Center
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198-0001
Country: USA
Contact_Voice_Telephone: (605) 594-6151
Contact_TDD/TTY_Telephone: (605) 594-6933
Contact_Facsimile_Telephone: (605) 594-6589
Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov
Hours_of_Service: 0730 - 1615 CST
Contact_Instructions: URL: http://edc.usgs.gov/eros-home.html
Browse_Graphic:
Browse_Graphic_File_Name: Digital Raster Graphic
Browse_Graphic_File_Description: Dover, Delaware
Browse_Graphic_File_Type: JPEG
Security_Information:
Security_Classification_System: None
Security_Classification: Unclassified
Security_Handling_Description: None
Native_Data_Set_Environment: Unix
Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The DRG uses a standard palette to ensure uniform color
throughout a particular map series. The RGB values for a particular
color, therefore, will remain consistent throughout that DRG series.
Although the color values of the DRG may sometimes match those
of the paper source map, a user will usually notice small differences
between the colors on the digital image and on the paper map. Also,
the quality of the user's monitor affects the DRG color displayed.
Although the DRG generally contains the complete content of the
source map, features may occasionally be blurred because of
substandard source materials. The DRG also may contain
misclassified pixels (color noise).
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.
Quantitative_Attribute_Accuracy_Assessment:
Attribute_Accuracy_Value: 00
Attribute_Accuracy_Explanation:
DRG's are examined to ensure color consistency within a series.
Inspections are performed on selected DRG's to ensure that both the
order of digital numbers (see table 2-2) and digital number values
are correct. Colors will be checked for color compliance to map
series and for major color differences between features on the DRG
and similar features on the source map. Color consistency
throughout each series is checked by comparing a DRG to its
neighboring quadrangles whenever possible.
Logical_Consistency_Report:
The USGS DRG is produced with the intention of replicating as close
as possible the original source map. Users of the DRG will note,
however, that a certain amount of "noise" can be discerned when
small areas are blown up or viewed under zoomed-in conditions. This
noise is in the form of random specks or pixels of color and halos
due to any number of factors, such as, the quality of the source,
the use of screens and patterns on the litho, and the unevenness of
ink due to saturation and absorption. Discontinuities or breaks in
linear features may also be present and are due to improper
calibration or usage of the scanner, the condition of the source,
and resampling. Descreening, quantizing, and noise filtering are
methods used to reduce noise, which, besides creating a more
aesthetically pleasing image, have the added benefit of reducing the
size of the image file. Removal of lithographic screen patterns is
preferred but not required.
Completeness_Report:
Image completeness is checked by visually inspecting a sampling of
DRG's. Each selected DRG will be examined for gaps (missing data)
in the main body of the map, the map collar, the overedge areas, and
any insets
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
A random sampling of DRG's will be accuracy tested. The accuracy
test will be performed by comparing the positions of UTM grid
intersections on the source graphic against the corresponding
location on the digital image. A visual inspection will determine
whether those coordinates fall within the pixels that define a grid
tick. DRG's duplicate the horizontal accuracy of its source.
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: 0
Horizontal_Positional_Accuracy_Explanation:
DRG's will retain the horizontal accuracy of the source maps. Most
USGS printed maps contain the National Map Accuracy Standards (NMAS)
note in the collar area. The NMAS states that for maps on
publication scales of 1:20,000 or smaller, not more than 10 percent
of the points tested shall be in error by more than 1/50 inch
measured on the publication scale. Test points must be "well-defined",
that is, easily visible or recoverable on the ground. For
DRG's this accuracy statement applies only to that area of the DRG
that falls within the neatline of the source map (excluding inset
areas). Overedge areas falling outside the transformation boundary
area (the map neatline), can exhibit anomalies or discrepancies.
These anomalies also will appear in the map inset areas and in the
map collar. For maps without the NMAS note, the horizontal accuracy
is unknown. However, the DRG will retain the accuracy of the source
map.
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
In the DRG the vertical positional accuracy is referenced in the DRG
collar.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: U.S. Geological Survey
Publication_Date: 0000
Title: USGS Topographic maps
Geospatial_Data_Presentation_Form: map
Other_Citation_Details:
The source for DRG's are the standard quadrangle format USGS
topographic maps as described in the Federal Geographic Data
Committee "Manual of Federal Geographic Data Products." They
include 1:20,000-, 1:24,000-, 1:25,000-, 1:30,000-, 1:63,360-,
1:100,000- and 1:250,000-scale topographic maps. Included in the
1:24,000- and 1:25,000-scale series are provisional (P) maps and
color orthophotomaps.
Type_of_Source_Media: paper
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 0000
Ending_Date: present
Source_Currentness_Reference: ground condition
Source_Citation_Abbreviation: USGS Topo
Source_Contribution:
The standard area of coverage of a DRG is the entire area printed
on a USGS standard series topographic map including the map collar,
any overedge areas, and insets. These standard series maps include:
7.5-minute map series: Conterminous United States, Hawaii, and
limited areas of Alaska at 1:24,000 and 1:25,000 scale.
7.5- by 15-minute map series: Covers limited areas of the
conterminous United States at 1:25,000 scale.
30- by 60-minute map series: Conterminous United States
Process_Step:
Process_Description:
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 500-1,000 dpi with an output file of
160-300 Mb in size. Removal of screens (descreening) and color
quantization to reduce the number of colors also takes place during
the scanning phase.
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. The USGS
program XSHAPES4 then performs a piecewise linear rubber sheet
transformation.
An output resolution of 2.4 meters (8.2 feet) is chosen to resample
the file to 250 dpi. The image file is converted to a TIFF 6.0
image and further reduced by converting the file to a run length
encoded PackBits compression (type 32773).
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.
Source_Used_Citation_Abbreviation: map1
Process_Date: 0000
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Rolla-ESIC
U.S. Geological Survey
Contact_Position: Customer Services Representative
Contact_Address:
Address_Type: mailing and physical address
Address: 1400 Independence Rd., MS231
City: Rolla
State_or_Province: MO
Postal_Code: 65401-2602
Country: USA
Contact_Voice_Telephone: 573-308-3577
Contact_Facsimile_Telephone: 573-308-3652
Contact_Electronic_Mail_Address: esic@mcmcmail.er.usgs.gov
Contact_Instructions: URL: http://mcmcweb.er.usgs.gov/drg/
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Pixel
Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview:
Each raster entity or pixel contains a digital number 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.
Entity_and_Attribute_Detail_Citation: Standards for Digital Raster Graphic.
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
U.S. Geological Survey
EROS Data Center
Contact_Person: Customer Services
Contact_Position: Customer Services Representative
Contact_Address:
Address_Type: mailing and physical address
Address:
Customer Services
U.S. Geological Survey
EROS Data Center
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198
Country: USA
Contact_Voice_Telephone: 605-594-6151
Contact_TDD/TTY_Telephone: 605-594-6933
Contact_Facsimile_Telephone: 605-594-6589
Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov
Hours_of_Service: 7:30 am to 4:00 pm CT
Contact_Instructions:
Automated Ordering. Your order is forwarded to Customer Services at the U.S.
Geological Survey's EROS Data Center. A Customer Services Representative
contacts you to discuss your order and your mode of payment.
Manual Ordering. Write down the ordering ID(s) for your item(s). Contact
Customer Services between the hours of 8:00 a.m. and 4:00 p.m. CST.
Resource_Description: DRG CD-R
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:
Format_Name: Tagged Image File Format (TIFF)
Format_Version_Number: version 6.0
Format_Specification:
Download WinCATS USGS DRG and DLG-O & DRG viewing software available
from USGS.
Format_Information_Content:
To facilitate file manipulation by the widest possible range of
potential users, data and text files on the CD-ROM conform to the
DOS "eight plus three" (8.3) file naming convention.
The associated DRG image (.TIF), world (.TFW), and metadata
(.FGD) files incorporate an intelligent data set name (DSN)
consisting of descriptive metadata wrapped around a standardized
kernel that describes the spatial location of the file. The
intent of this file naming protocol is to positively identify the
spatial identity of the file and describe its categoric
identity.
The DSN is designed to geographically locate DRG's of quadrangles
using the 7.5-minute grid, clearly identifying those that fall
exactly on the grid. DRG's that are not aligned with the
7.5-minute grid can be named with this convention but additional
consideration is required to relate these undersize, oversize, or
offset quadrangles to their most logical and unique 7.5-minute
grid location.
File_Decompression_Technique: PackBits
Transfer_Size: 5 to 15 megabytes.
Digital_Transfer_Option:
Offline_Option:
Offline_Media: CD-ROM
Recording_Capacity:
Recording_Density: 650
Recording_Density_Units: megabytes
Recording_Format: ISO 9660
Compatibility_Information: None
Fees:
The current costs are available at:
URL: http://edc.usgs.gov/glis/hyper/order_info/prices#DRG_CD
DRG File size may necessitate distribution on multiple CD-ROMs
Ordering_Instructions:
Dataset searching and ordering capabilities are available through the
Global Land Information System (GLIS) at:
URL: http://edc.usgs.gov/webglis
Turnaround: ASAP
Technical_Prerequisites: Adobe Acrobat Reader 2., CD-ROM drive
Available_Time_Period:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1997
Metadata_Reference_Information:
Metadata_Date: 19970904
Metadata_Review_Date: 19970904
Metadata_Future_Review_Date: 19971230
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
U.S. Geological Survey
EROS Data Center
Contact_Position: Customer Services Representative
Contact_Address:
Address_Type: mailing and physical address
Address:
Customer Services
U.S. Geological Survey
EROS Data Center
City: Sioux Falls
State_or_Province: SD
Postal_Code: 57198-0001
Country: USA
Contact_Voice_Telephone: (605) 594-6151
Contact_TDD/TTY_Telephone: (605) 594-6933
Contact_Facsimile_Telephone: (605) 594-658
Contact_Electronic_Mail_Address: custserv@edcmail.cr.usgs.gov
Hours_of_Service: 0700 - 1615 CST
Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: June 8, 1994
Metadata_Time_Convention: local time
Metadata_Access_Constraints: None
Metadata_Use_Constraints: None
Metadata_Security_Information:
Metadata_Security_Classification_System: None
Metadata_Security_Classification: Unclassified
Metadata_Security_Handling_Description: None