Open AccessPESQ‐Based Selection of Efficient Partial Encryption Set for Compressed Speech
Author(s) -
Yang HaeYong,
Lee KyungHoon,
Lee SangHan,
Ko SungJea
Publication year - 2009
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.09.0108.0508
Subject(s) - pesq , encryption , computer science , codec , speech coding , speech recognition , selection (genetic algorithm) , bitstream , distortion (music) , selection algorithm , algorithm , speech enhancement , artificial intelligence , computer network , computer hardware , decoding methods , noise reduction , amplifier , bandwidth (computing)
Adopting an encryption function in voice over Wi‐Fi service incurs problems such as additional power consumption and degradation of communication quality. To overcome these problems, a partial encryption (PE) algorithm for compressed speech was recently introduced. However, from the security point of view, the partial encryption sets (PESs) of the conventional PE algorithm still have much room for improvement. This paper proposes a new selection method for finding a smaller PES while maintaining the security level of encrypted speech. The proposed PES selection method employs the perceptual evaluation of the speech quality (PESQ) algorithm to objectively measure the distortion of speech. The proposed method is applied to the ITU‐T G.729 speech codec, and content protection capability is verified by a range of tests and a reconstruction attack. The experimental results show that encrypting only 20% of the compressed bitstream is sufficient to effectively hide the entire content of speech.