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An Efficient Objective Intelligibility Measure for Frequency Domain Scramblers


An objective performance measure is proposed to evaluate the intelligibility of a speech signal having its frequency subbands permuted. The proposed tool can be used to generate efficient keys for frequency domain scramblers as well as to assess the results of cryptanalysis.



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Correspondence to AMCR Borzino or JA Apolinário Jr..

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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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Borzino, A., Apolinário, J. & da Silva, D. An Efficient Objective Intelligibility Measure for Frequency Domain Scramblers. EURASIP J. on Info. Security 2007, 032028 (2008).

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  • Frequency Domain
  • Speech Signal
  • Objective Performance
  • Data Security
  • Intelligibility Measure