During the vectorization process, the satellite imagery was displayed on a computer screen using ESRI's ArcGIS 8.2 software. In order to obtain the highest degree of accuracy from the imagery, the one-meter panchromatic imagery was used as a base layer for digitizing. In an effort to better visualize the land-water interface, the one-meter imagery was overlaid on top of the four-meter multispectral imagery using a 35 % transparency value. The near-infrared band (Band 4) was used in the display of the multispectral imagery. The resultant base layer contained the one-meter resolution of the panchromatic imagery and the colorization of the four-meter imagery. The display was zoomed to the image resolution of the panchromatic imagery and the shoreline was manually digitized. All lines are coded with length, ID, origin, and source
Note - Areas of the shoreline that were obscured by cloud cover were digitized from USGS Digital Rater Graphics (DRGs). The USGS DRG for Tinian had to be adjusted in the x and y directions using ERDAS Imagine 8.5 to match the IKONOS imagery. This shoreline was produced during a two year period ending 20030923.