Anew noise removal and enhancement method of infrared image
Ying Chen · Journal of Sichuan University · 2012
The SNR(Signal-to-Noise) of infrared image is generally very low,In this point,a new denoising algorithm based on Prewitt operator,named IDMF(Improved Directional Median Filter) is proposed. First,the Prewitt operator is used to calculate the gradient direction of TBA(Target-and-Background Area) and the corresponding contour direction is calculated.Second,the median filter is applied to remove the noise in this direction and the detail information can be farthest preserved.Meanwhile, considering the low overall gray distribution of the infrared image and its low contrast,a new contrast enhancement algorithm combined of a partial contrast enhancement and overall contrast enhancement is proposed.The Roberts cross gradient operator is used to achieve the partial enhancement and the piecewise nonlinear function is introduced to the overall contrast enhancement.Experimental results show that our method is effective.