During the course of turbulence-degraded image restoration,an improved image restoration algorithm is proposed based on APEX method.The algorithm improves the course of estimating point spread function(PSF) in the APEX method by utilizing the basic principle of the APEX method and combining the frequency-spectrum information of real turbulence-degraded image.It substitutes the single estimation by synthetic estimation in multi-direction.So the method reduces the error of PSF estimation,and enhances the stab...