A novel tap coefficients codec method based on DC offset(DCTCC)is proposed to overcome the redundant shortcoming in describing tap coefficients of adaptive loop filter in the video coding. Firstly
DCTCC performs compensating on the DC offset between the restored picture and the original picture. Then
the Wiener filter is designed in terms of the compensated picture as the filter input and the original picture as the desired response to further compensate AC distortion in restored picture. Finally
only the non-center tap coefficients are coded and transmitted
while the value of the center tap coefficient is derived by the feature that the sum of the tap coefficients equals 1
so that the transmission efficiency of the filter parameters is improved. Experimental results with test sequences in different formats show that DCTCC outperforms the existing algorithm with adaptive loop filter. Comparisons with H.264/AVC show that the coding efficiency of DCTCC has an improvement up to 26.31%.
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references
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