IDENTIFICATION_INFORMATION : CITATION : CITATION_INFORMATION : ORIGINATOR = U.S. Tennessee Valley Authority, Geographic Information and Engineering PUBLICATION_DATE = 19960710 TITLE = Gilt Edge, TN GEOSPATIAL_DATA_PRESENTATION_FORM = map DESCRIPTION : ABSTRACT = The Digital Raster Graphic (DRG) is a raster image of a scanned USGS topographic map georeferenced to the Universal Transverse Mercator grid. 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. SUPPLEMENTAL_INFORMATION = The Universal Transverse Mercator meters coordinates of pixel 1,1 are x = 237957.06 y = 3946831.57 TIME_PERIOD_OF_CONTENT : TIME_PERIOD_INFORMATION : SINGLE_DATE/TIME : CALENDAR_DATE = 1975 CURRENTNESS_REFERENCE = Ground Condition STATUS : PROGRESS = Complete MAINTENANCE_AND_UPDATE_FREQUENCY = Irregular SPATIAL_DOMAIN : BOUNDING_COORDINATES = WEST_BOUNDING_COORDINATE = -89.875 EAST_BOUNDING_COORDINATE = -89.750 NORTH_BOUNDING_COORDINATE = 35.625 SOUTH_BOUNDING_COORDINATE = 35.500 KEYWORDS : THEME : THEME_KEYWORD_THESAURUS = None THEME_KEYWORD = digital raster graphic THEME_KEYWORD = DRG THEME_KEYWORD = topographic map PLACE : 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. PLACE_KEYWORD = US 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. PLACE_KEYWORD = TN ACCESS_CONSTRAINTS = None USE_CONSTRAINTS = Acknowledgement of the U.S. Tennessee Valley Authority, Geographic Partnerships Program would be appreciated in products derived from these data. DATA_SET_CREDIT = This DRG was produced through the Tennessee Valley Authority, Geographic Partnerships program. External partners on the project included the Tennessee Department of Transportation and the Natural Resources Conservation Service (Tennessee). POINT_OF_CONTACT : CONTACT_INFORMATION : CONTACT_ORGANIZATION_PRIMARY : CONTACT_ORGANIZATION = U.S. Tennessee Valley Authority, Geographic Information and Engineering CONTACT_ADDRESS : ADDRESS_TYPE = mailing address ADDRESS = HB 2A-C, 1101 Market St. CITY = Chattanooga STATE_OR_PROVINCE = TN POSTAL_CODE = 37402-2801 CONTACT_VOICE_TELEPHONE = 1 423 751 8640 CONTACT_TDD/TTY_TELEPHONE = 1 423 751 8500 CONTACT_FACSIMILE_TELEPHONE = 1 423 751 8525 CONTACT_ELECTRONIC_MAIL_ADDRESS = mapstore@tva.gov DATA_QUALITY_INFORMATION : ATTRIBUTE_ACCURACY : ATTRIBUTE_ACCURACY_REPORT = The DRG is an 8-bit color image which employs a color palette to ensure uniform colors throughout a particular DRG series. That is to say, if a color is defined as having a particular RGB value, for all DRG's within that series, the RGB value is the same. LOGICAL_CONSISTENCY_REPORT = Not Applicable COMPLETENESS_REPORT = The Digital Raster Graphic (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 digital raster graphic 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 : HORIZONTAL_POSITIONAL_ACCURACY_REPORT = The horizontal position accuracy is that of the original map. The map scanning process introduces an insignificant amount of distortion. The coordinate system of the DRG is Universal Transverse Mercator and may be different from that of the original map (as shown on the map image collar). VERTICAL_POSITIONAL_ACCURACY : VERTICAL_POSITIONAL_ACCURACY_REPORT = Refer to the DRG collar or the collar of the published map for information about vertical positional accuracy. LINEAGE : SOURCE_INFORMATION : SOURCE_CITATION : CITATION_INFORMATION : ORIGINATOR = USGS PUBLICATION_DATE = 1975 TITLE = Gilt Edge, TN GEOSPATIAL_DATA_PRESENTATION_FORM = map PUBLICATION_INFORMATION : PUBLICATION_PLACE = Reston, VA PUBLISHER = USGS SOURCE_SCALE_DENOMINATOR = 24000 TYPE_OF_SOURCE_MEDIA = paper SOURCE_TIME_PERIOD_OF_CONTENT : TIME_PERIOD_INFORMATION : SINGLE_DATE/TIME : CALENDAR_DATE = 1975 SOURCE_CURRENTNESS_REFERENCE = ground condition SOURCE_CITATION_ABBREVIATION = map1 SOURCE_CONTRIBUTION = The source map which was scanned to produce the digital raster graphic. PROCESS_STEP : PROCESS_DESCRIPTION = The production procedures, instrumentation, hardware and software used in the collection of standard U.S. Geological Survey (USGS) Digital Raster Graphic (DRG) products vary depending on systems used at the contract, cooperator or National Mapping Division (NMD) production sites. The majority of DRG datasets are acquired through government contract. The process step describes, in general, the process used in the production of standard USGS DRG datasets. 1. Production of a DRG begins with the scanning of a paper 7.5-minute topographic map (map1) on a high resolution scanner. The map is scanned at 500 dpi and produces an output file of between 15-75 mb in size. 2. Color classification to reduce the number of colors and assigning the standard DRG colors takes place during the scanning phase. 3. The image is then descreened (removal of map printing screens) to reduce file size. 4. The raw scan file is then transformed and georeferenced using plane coordinates of the 16 2.5-minute grid ticks which are obtained using the Intergraph Projection Manager program and stored in a ground control file. Those 16, 2.5-minute ticks are interactively visited and assigned their respective grid coordinate. Intergraph IRASC program then performs an affine coordinate transformation warp. The image is subsampled to 250 dots per inch (dpi) to produce resolution of 2.4 meters (8.0 feet) in the warp process. 5. The image file is converted to a Tagged Image File Format (TIFF), and further reduced by converting the file to a run length encoding PackBit compression (type 32773). 6. Prior to archival the DRG undergoes the following quality assurance procedures; a. All DRG files are inspected to ensure that they are geometrically consistent with normal map presentation. b. 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. c. Selected DRG's are checked for georeferencing accuracy by comparing the book value of latitude and longitude tick marks to corresponding tick intersections in the DRG image. d. Transformations are checked on selected DRG's by comparing the positions of well defined points such as plane grid intersections in the graphic product to the corresponding image points in the DRG. SOURCE_USED_CITATION_ABBREVIATION = map1 PROCESS_DATE = 19960710 SPATIAL_DATA_ORGANIZATION_INFORMATION : DIRECT_SPATIAL_REFERENCE_METHOD = Raster RASTER_OBJECT_INFORMATION : RASTER_OBJECT_TYPE = Pixel ROW_COUNT = 7079 COLUMN_COUNT = 5760 SPATIAL_REFERENCE_INFORMATION : HORIZONTAL_COORDINATE_SYSTEM_DEFINITION : PLANAR : GRID_COORDINATE_SYSTEM : GRID_COORDINATE_SYSTEM_NAME = Universal Transverse Mercator UNIVERSAL_TRANSVERSE_MERCATOR UTM_ZONE_NUMBER = 16 Transverse_Mercator LONGITUDE_OF_CENTRAL_MERIDIAN = -87.000 LATITUDE_OF_PROJECTION_ORIGIN = 0.0 FALSE_EASTING = 500000.0 FALSE_NORTHING = 0.0 SCALE_FACTOR_AT_CENTRAL_MERIDIAN = 0.9996 PLANAR_COORDINATE_INFORMATION : PLANAR_COORDINATE_ENCODING_METHOD = row and column COORDINATE_REPRESENTATION : ABSCISSA_RESOLUTION = 2.4 ORDINATE_RESOLUTION = 2.4 PLANAR_DISTANCE_UNITS = meters GEODETIC_MODEL = HORIZONTAL_DATUM_NAME = North American Datum of 1927 ELLIPSOID_NAME = Clark 1866 SEMI-MAJOR_AXIS = 6378206.40 DENOMINATOR_OF_FLATTENING_RATIO = 294.98 ENTITY_AND_ATTRIBUTE_INFORMATION : OVERVIEW_DESCRIPTION : ENTITY_AND_ATTRIBUTE_OVERVIEW = Each raster entity or pixel contains a color index from 0 through 12 referencing a color palette of RGB values from O through 255 in which the standard colors used in the DRG are defined. Index 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 ENTITY_AND_ATTRIBUTE_DETAIL_CITATION = Draft Standards for Digital Raster Graphic. DISTRIBUTION_INFORMATION : DISTRIBUTOR : CONTACT_INFORMATION : CONTACT_ORGANIZATION_PRIMARY : CONTACT_ORGANIZATION = U.S. Tennessee Valley Authority, Geographic Information and Engineering, Map Information and Records Team. CONTACT_ADDRESS : ADDRESS_TYPE = mailing address ADDRESS = HB 2A-C, 1101 Market St. CITY = Chattanooga STATE_OR_PROVINCE = TN POSTAL_CODE = 37402-2801 CONTACT_VOICE_TELEPHONE = 1 800 MAPSTVA CONTACT_TDD/TTY_TELEPHONE = 1 423 751 8500 CONTACT_FACSIMILE_TELEPHONE = 1 423 751 8525 CONTACT_ELECTRONIC_MAIL_ADDRESS = mapstore@tva.gov DISTRIBUTION_LIABILITY = Although these data have been processed successfully on a computer system at the U.S. Tennessee Valley Authority (TVA), no warranty expressed or implied is made by the TVA regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. The TVA 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 30 days from the date of this shipment from the ordering site. STANDARD_ORDER_PROCESS : DIGITAL_FORM : DIGITAL_TRANSFER_INFORMATION : FORMAT_NAME = TIFF FORMAT_VERSION_NUMBER = 5.0 FILE_DECOMPRESSION_TECHNIQUE = PackBit DIGITAL_TRANSFER_OPTION : OFFLINE_OPTION : OFFLINE_MEDIA = CD-ROM RECORDING_FORMAT = ISO 9660; DRG image files with corresponding metadata files. FEES = Contact TVA Map Store at 1-800-MAPSTVA for current price. METADATA_REFERENCE_INFORMATION : METADATA_DATE = 19960710 METADATA_CONTACT : CONTACT_INFORMATION : CONTACT_ORGANIZATION_PRIMARY : CONTACT_ORGANIZATION = U.S. Tennessee Valley Authority, Geographic Information and Engineering. CONTACT_ADDRESS : ADDRESS_TYPE = mailing address ADDRESS = HB 2A-C, 1101 Market St. CITY = Chattanooga STATE_OR_PROVINCE = TN POSTAL_CODE = 37402-2801 CONTACT_VOICE_TELEPHONE = 1 423 751 8640 CONTACT_TDD/TTY_TELEPHONE = 1 423 751 8500 CONTACT_FACSIMILE_TELEPHONE = 1 423 751 8525 CONTACT_ELECTRONIC_MAIL_ADDRESS = mapstore@tva.gov METADATA_STANDARD_NAME = Content Standards for Digital Geospatial Metadata METADATA_STANDARD_VERSION = 19940608