Video Noise Reduction in 3-D Mixed Transform Domain Using Its Efficient Wavelet Structure

In this paper, we propose a novel 3-D mixed transform based video denoising scheme for additive white gaussian noise. The 3-D mixed transform consists of lapped biorthogonal transform (LBT) in vertical and horizontal directions and discrete cosine transform (DCT) in temporal direction. The efficient wavelet structure of 3-D mixed transform coefficients is used for denoising the video data. The concept of wavelet structure of 3-D mixed transform coefficients is taken from our recent successful lossy color image compression scheme. The wavelet structure of 3-D mixed transform coefficients allow to use efficient wavelet based image denoising algorithms without wavelet transform. We use the approximate minimum mean square error (MMSE) estimation procedure to denoise each individual slice of 3-D mixed transform coefficients. We propose to use the simple selective recursive temporal filtering with the proposed denoising scheme which improves the average peak signal to noise ratio (PSNR) further by 1 dB - 2 dB. Experimental results demonstrate that the proposed scheme shows encouraging results when compared to many existing complex wavelet based denoising schemes both in terms of PSNR and visual quality.