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arXiv · 2207.14463

Low-Complexity Loeffler DCT Approximations for Image and Video Coding

D. F. G. Coelho·R. J. Cintra·F. M. Bayer·S. Kulasekera·A. Madanayake·P. A. C. Martinez·T. L. T. Silveira·R. S. Oliveira·V. S. Dimitrov
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Abstract

This paper introduced a matrix parametrization method based on the Loeffler discrete cosine transform (DCT) algorithm. As a result, a new class of eight-point DCT approximations was proposed, capable of unifying the mathematical formalism of several eight-point DCT approximations archived in the literature. Pareto-efficient DCT approximations are obtained through multicriteria optimization, where computational complexity, proximity, and coding performance are considered. Efficient approximations and their scaled 16- and 32-point versions are embedded into image and video encoders, including a JPEG-like codec and H.264/AVC and H.265/HEVC standards. Results are compared to the unmodified standard codecs. Efficient approximations are mapped and implemented on a Xilinx VLX240T FPGA and evaluated for area, speed, and power consumption.

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D. F. G. Coelho, R. J. Cintra, F. M. Bayer, S. Kulasekera, A. Madanayake, P. A. C. Martinez, T. L. T. Silveira, R. S. Oliveira, V. S. Dimitrov. 2022-07-29. Low-Complexity Loeffler DCT Approximations for Image and Video Coding. https://doi.org/10.3390/jlpea8040046

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