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DCT_M model for excitation parameter in low bit rate vocoder

  • Research Article
  • Published:
Frontiers of Electrical and Electronic Engineering in China

Abstract

The description precision of an excitation signal greatly influences the quality of reconstructed speech in low bit rate vocoders. To improve the reconstruction quality, the DCT_M model is proposed to express the excitation spectral parameter, which transforms the variable length vector to fixed dimension vector through DCT transformation. It then quantizes the fixed length vector using multi-stage vector quantization. Tests show that the proposed method can keep the shape of the entire spectral envelope and reduce model error thus greatly improve the description precision. Test results in the sine excitation linear prediction (SELP) vocoder show that the DCT_M model can improve the naturalness of reconstructed speech, with subjective test score of 65%.

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References

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Authors and Affiliations

  1. State Key Laboratory on Microwave and Digital Communications, Department of Electronic Engineering, Tsinghua University, Beijing, 100084, China

    Xiaoyan Dang & Kun Tang

Authors
  1. Xiaoyan Dang
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  2. Kun Tang
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Corresponding author

Correspondence to Xiaoyan Dang.

Additional information

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Translated from Journal of Tsinghua University (Science and Technology), 2007, 47(4): 578–580 [译自: 清华大学学报(自然科学版)]

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Dang, X., Tang, K. DCT_M model for excitation parameter in low bit rate vocoder. Front. Electr. Electron. Eng. Ch 3, 204–207 (2008). https://doi.org/10.1007/s11460-008-0043-1

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  • DOI: https://doi.org/10.1007/s11460-008-0043-1

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