N stage non-separable two dimensional wavelet transform for reduction of rounding errors
نویسندگان
چکیده
This paper proposes an N stage "non-separable" two-dimensional (2D) wavelet transform (WT) for lossless / lossy unified coding of digital images. The proposed method achieves better coding performance especially at high bit rate since it has fewer rounding operations. We convert the conventional "separable" 2D WT into "non-separable" one without changing its frequency characteristics so that the number of the rounding operations is reduced and also the proposed method has compatibility with the conventional one. Effectiveness of the proposed coding system is confirmed experimentally and theoretically.
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