Perception-based partial encryption of compressed speech

摘要: Mobile multimedia applications, the focus of many forthcoming wireless services, increasingly demand low-power techniques implementing content protection and customer privacy. In this paper low complexity perception-based partial encryption schemes for speech are presented. Speech compressed by a widely-used coding algorithm, ITU-T G.729 standard at 8 kb/s, is partitioned in two classes, one, most perceptually relevant, to be encrypted, other, left unprotected. Two partial-encryption developed, low-protection scheme, aimed preventing kinds eavesdropping high-protection based on larger share important bits meant perform as well full bitstream. The about 45% bitstream, achieves comparable that obtained encryption, verified both objective measures formal listening tests. For little 30% bitstream virtually eliminates intelligibility remaining perceptual information. Low-power, portable devices could therefore achieve very high levels speech-content only 30-45% computational load current techniques, freeing resources other tasks enabling longer battery life.