[ToC]

 

Hal Hellman, Controlled Guidance Systems, Howard W. Sams & Co., 1967

MOVEMENT OF THE SUN CHANGES APPARENT SHAPE OF THE BUILDING

Matching a live scene with a stored map of the area is called correlation. A number of techniques are being explored which, while promising, cause tremendous problems. For example, attempting to correlate terrain against reconnaissance pictures taken only hours before can be burdensome because of changes in lighting and shadowing [see right], the angles from which they are viewed, and so on.