Analog spatial-filtering techniques are applied to the restoration of images degraded by propagation through random media. The image-forming system is assumed to be linear and stationary so that optically dividing the degraded image spectrum by the degrading transfer function suppresses the degradation. Images are stored and filters fabricated by controlled photographic methods. Preliminary experimental results have successfully demonstrated the feasibility of this filtering technique. In particular, degradations produced by cosine fringes and hot turbulent air were suppressed and enhanced images obtained.
PETER F. MUELLER and GEORGE O. REYNOLDS, "Image Restoration by Removal of Random-Media Degradations," J. Opt. Soc. Am. 57, 1338-1344 (1967)