Process and apparatus for cross-correlating digital imagery

摘要

The present invention involves a system and method for processing information from high resolution data from maps, aerial photographs and other spatial data with low resolution data from limitation in order to accurately identify changes in the studied areas. The system and method relies upon a vectorized database which has been classified according to topographical features. Change is defined by a Z-statistic. The Z-statistic is calculated in a two-pass cross-correlation technique when pixel brightnesses are compared to a mean brightness for the typical topographical class and to a standard deviation for that class. The normalized difference values are accumulated across different bands, are scaled and then compared to a threshold which defines high, medium and low change values. A map is automatically produced illustrating areas of significant change.