Track: Database Design and Automation
Practical Guidance on the Use of Raster Graphics
Dave NouzaRaster graphics can provide a useful backdrop to a mapping project. Unfortunately, there is no direct method for removing the image boundary from raster graphics to allow multiple images to be aligned and edgematched. As well, it can be difficult to properly align multiple images without areas of NODATA being introduced into the images. By using several of ARC GRID functions it is possible to remove the legend surrounding a raster graphic and merge adjacent images to fill in NODATA areas. This results in a seamless boundary between images. Several techniques for accomplishing these tasks are examined in detail. Although the specific procedures discussed in this paper are geared toward utilizing USGS Digital Raster Graphic (DRG) images, the steps generally can be applied to the processing of any set of raster graphics.
Dave Nouza
National Institute for Environmental Renewal
1300 Old Plank Road
Mayfield, PA 18433
USA
Telephone: 717-282-6456, ext 121
Fax: 717-282-3381
E-mail: nouza@nier.org