Digital raster graphic

A digital raster graphic (DRG) is a digital image resulting from scanning a paper USGS topographic map for use on a computer. DRGs created by USGS are typically scanned at 250 dpi and saved as a TIFF. The raster image usually includes the original border information, referred to as the "map collar". The map file is UTM projected and georeferenced to the surface of the earth. DRG's are regularly used in GIS applications. DRGs were first produced in 1995.

A small portion of a USGS DRG

See also

• GeoTIFF

External links

• Libre Map Project
  • All 50 States USGS Topographic Maps on the Internet Archive
  • USGS Topographic Maps of ALL 50 States
• USGS Sites
  • Digital Raster Graphics
• Kentucky Raster Graphics Image Download Center
• Montana State Library Digital Raster Graphics download page
• Pennsylvania Spatial Data Access sites
• FTP site, DRGs for West Virginia (free)^{[permanent dead link]}
• FTP site, DRGs for New York (free)^{[permanent dead link]}
• FTP site, DRGs for Virginia (free)^{[permanent dead link]}
• FTP site, DRGs for Maryland (free)^{[permanent dead link]}
• FTP site, DRGs for Washington DC (free)^{[permanent dead link]}
• FTP site, DRGs for Delaware (free)^{[permanent dead link]}
• FTP site, DRGs for North Carolina (free)^{[permanent dead link]}
• Texas Natural Resources Information System