Each NAPP photograph covers approximately 9km X 9km. The Western Mapping Center of the USGS in Menlo Park scanned the photographs at a resolution of 25 microns, or approximately 1 meter ground resolution. They also determined the altitude and orientation of the camera for each photograph using a space resection and block-adjustment algorithm.
An SRI system called TerraForm was used to rectifiy each of the images. 30 of the images were converted to black/white and were then mosaicked together to form a 35K x 24K image (about 1 GByte in size). You can view a low-resolution version of the image by clicking on the icon at the beginning of this section or by viewing parts of the data set using the Tile Set Manager Web Interface by browsing the SRI database and selecting the "ntc-1-lvcs-30scene" GeoPyramid.
The processing was done on the CM-200 Connection Machine at the Minnesota Supercomputer Center, Inc. (MSCI) using SRI's TerraForm system. Unfortunately, the StarLisp language that TerraForm was written in is no longer supported, so further processing of the images will not be possible until the port of TerraForm to a distributed processing environment is complete.
The TerraVision home page shows
views from a smaller (2 image) dataset. They're in the original CIR
pseudo-color format. A couple of black/white views of the larger
dataset are available below.
Points of contact for TerraVision: Stephen Q. Lau, or Yvan G. Leclerc. Wed Jul 27 1994
(*) TerraVision is a trademark of SRI International.