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Warped Discrete Cosine Transform-Based Low Bit-Rate Block Coding Using Image Downsampling


This paper presents warped discrete cosine transform (WDCT)-based low bit-rate block coding using image downsampling. While WDCT aims to improve the performance of conventional DCT by frequency warping, the WDCT has only been applicable to high bit-rate coding applications because of the overhead required to define the parameters of the warping filter. Recently, low bit-rate block coding based on image downsampling prior to block coding followed by upsampling after the decoding process is proposed to improve the compression performance for low bit-rate block coders. This paper demonstrates that a superior performance can be achieved if WDCT is used in conjunction with image downsampling-based block coding for low bit-rate applications.


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Correspondence to Sarp Ertürk.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Ertürk, S. Warped Discrete Cosine Transform-Based Low Bit-Rate Block Coding Using Image Downsampling. EURASIP J. Adv. Signal Process. 2007, 043948 (2007).

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