The characteristics of digital audio such as a large quantity of data
strong correlation and high redundancy
make it difficult to meet real-time security to encrypt digital audio by using conventional encryption algorithms. An audio cryptography scheme based on binary audio is proposed by using the auditory properties of human being. In order to reduce the amount of audio data
the secret audio is transformed into binary audio by halftone as in the image process. The basic array of(k
n)threshold in visual cryptography scheme is used to share the binary audio so that correlations in audio data is removed. The secret audio information can be directly decrypted through human auditory system by synchronously playing any k shares of the binary audio
but synchronously playing any m(m<k)shares does not disclose any information. Experiments show that the encrypted audio by the proposed scheme has high randomicity and security. Comparisons with original secret audio show that although the decrypted secret voice has some distortion
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