Correction of atmospheric turbulence degraded sequences using grid smoothing

Abstract

Heat scintillation occurs due to the index of refraction of air decreasing with an increase in air temperature, causing objects to appear blurred and waver slowly in a quasi-periodic fashion. This imposes limitations on sensors used to record images over long distances resulting in a loss of detail in the video sequences. A method of filtering turbulent sequences using grid smoothing is presented that can be used to either extract a single geometrically improved frame or filter an entire turbulent sequence. The extracted frame is in general sharper than when utilising simple GFATR (Generalized First Average Then Register). It also better preserves edges and lines as well as being geometrically improved. © 2011 Springer-Verlag.