Fast and effective image denoising is critical for improving the accuracy of laser active imaging guidance.Focusing on the speckle noise in imaging,a denoising algorithm based on the combination of improved wavelet threshold denoising algorithm and integral image based non-local means filtering is proposed.Firstly,noise analysis of laser active imaging is performed.Secondly,speckle noise is converted from multiplicative noise to additive noise by logarithmic transform.Then,the image is decomposed into two layers by wavelet transform:the improved wavelet threshold denoising algorithm is used for the high-frequency part of the first layer,and non-local means filtering is used for the high-frequency part of the second layer.Finally,inverse transforms are carried out and the denoised intensity image is obtained.Theoretical analysis and experimental results show that the proposed algorithm has fine denoising performance and the details of image are well protected.Meanwhile,the proposed algorithm meets the requirements of laser active imaging guidance for real-time image denoising.