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A comparative study of transforms for use in digital audio data compression.

B E Rulon·M F Shaw·K D Donohue
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Abstract

This paper provides a subjective quality analysis of transforms used in audio compression algorithms for a class of music signals. A 34-subject listener test compares three transforms in conjunction with an MPEG I layer 1 compression scheme. One test compares the performances of the discrete wavelet packet transform (DWPT) and the modified discrete cosine transform (MDCT) used in MPEG. Another test compares the performances of a DWPT eight-level nonuniform critical-band split and a DWPT five-level uniform subband split. Results indicate that the critical-band split provides significantly better quality than the uniform subband split for sounds with tonal and strong low-frequency content, while the DWPT outperforms the MDCT with significant improvement for nontonal sounds.

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BibTeXRIS

B E Rulon, M F Shaw, K D Donohue. 2000. A comparative study of transforms for use in digital audio data compression.. https://doi.org/10.1121/1.429479

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