Tatouage audio par EMD

In this paper a new adaptive audio watermarking algorithm based on Empirical Mode Decomposition (EMD) is introduced. The audio signal is divided into frames and each one is decomposed adaptively, by EMD, into intrinsic oscillatory components called Intrinsic Mode Functions (IMFs). The watermark and the synchronization codes are embedded into the extrema of the last IMF, a low frequency mode stable under different attacks and preserving audio perceptual quality of the host signal. The data embedding rate of the proposed algorithm is 46.9–50.3 b/s. Relying on exhaustive simulations, we show the robustness of the hidden watermark for additive noise, MP3 compression, re-quantization, filtering, cropping and resampling. The comparison analysis shows that our method has better performance than watermarking schemes reported recently

Quaternion-based Encryption/Decryption of Audio Signal Using Digital Image as Variable Key

With the rapid growth of communication technology, cryptography plays a significant role in securing and verification of information exchanged via public communication channels.   The current paper introduces a novel method for encrypting/decrypting audio signal using a selected digital image as a complicated key and cover for audio signal.  Each sample of the audio signal is combined with the values of the three color components of a pixel fetched from the cover image yielding a quaternion number.   The absolute value of this quaternion number is then transmitted and when received, the original value of the audio sample can be extracted using simple quaternion mathematics. A second level of complexity can be added to this approach by applying one of the well-known cryptographic techniques (symmetric or asymmetric).   The suggested approach is implemented using Matlab simulation software and the generated audio signal is compared with the original one using some performance metrics.  The obtained results show that the proposed approach is robust and more secure against cryptanalysis attacks

DWT-SMM-based audio steganography with RSA encryption and compressive sampling

Problems related to confidentiality in information exchange are very important in the digital computer era. Audio steganography is a form of a solution that infuses information into digital audio, and utilizes the limitations of the human hearing system in understanding and detecting sound waves. The steganography system applies compressive sampling (CS) to the process of acquisition and compression of bits in binary images. Rivest, Shamir, and Adleman (RSA) algorithms are used as a system for securing binary image information by generating encryption and decryption key pairs before the process is embedded. The insertion method uses statistical mean manipulation (SMM) in the wavelet domain and low frequency sub-band by dividing the audio frequency sub-band using discrete wavelet transform (DWT) first. The optimal results by using our system are the signal-to-noise ratio (SNR) above 45 decibel (dB) and 5.3833 bit per second (bps) of capacity also our system has resistant to attack filtering, noise, resampling and compression attacks

Методика скрытой передачи данных при связи через воздушный аудиоканал

This article proposes a method for secure data transmission in the audible domain of the frequency spectrum of the air environment. Specifically, it proposes the method of construction, embedding, extraction and recovery of a hidden signal transmitted through the air audio channel. The hidden signal consists of two parts. One part is used for synchronization, and the other one is used for carrying information. The basis of the synchronization part is the Kasami sequence, whereas the basis of the information part is a code word of the binary BCH code. Both parts of the hidden signal are obtained through special encoding of their binary elements. The encoding uses Gold sequences and RZ codes. Speech or music are used as a carrier signal. The hidden signal is embedded in the frequency domain of the carrying signal. The embedding is based on amplitude modulation of individual spectral components of the carrying signal. The article discusses the possibility of restoring the hidden signal after the transmission of the stego-audio signal through the air audio channel. The article presents the results of simulation modeling and field experiments of transmission of the stego-audio signal through the air audio channel.В этой статье предлагается методика скрытой передачи информации в слышимой области частотного спектра воздушной среды, а именно — построения, внедрения, выделения и восстановления скрываемого сигнала, когда передача осуществляется через воздушный аудиоканал. Скрываемый сигнал состоит из двух частей. Одна часть используется для синхронизации, а другая часть — информационная. В основе синхронизационной части лежит последовательность Касами, тогда как в основе информационной — кодовое слово кода БЧХ. Обе части скрываемого сигнала получаются путем специального кодирования своих двоичных элементов. При выполнении этого кодирования используются последовательности Голда и RZ коды. В качестве скрывающего или несущего сигнала используется аудиосигнал, который может представлять собой как речь, так и музыку. Построение стегоаудиосигнала выполняется путем внедрения скрываемого сигнала в частотную область скрывающего сигнала. Внедрение представляет собой амплитудную модуляцию отдельных спектральных составляющих скрывающего сигнала. В статье аналитически рассматривается вопрос возможности восстановления скрываемого сигнала, после передачи стегоаудиосигнала через воздушный аудиоканал. Статья снабжена результатами имитационного моделирования и натурных экспериментов передачи стегоаудиосигнала через воздушный аудиоканал

A robust audio watermarking scheme based on reduced singular value decomposition and distortion removal

This paper presents a blind audio watermarking algorithm based on the reduced singular value decomposition(RSVD). A new observation on one of the resulting unitary matrices is uncovered. The proposed scheme manipulates coefficients based on this observation in order to embed watermark bits. To preserve audio fidelity a threshold- based distortion control technique is applied and this is further supplemented by distortion suppression utilizing psychoacoustic principles. Test results on real music signals show that this watermarking scheme is in the range of imperceptibility for human hearing, is accurate and also robust against MP3 compression at various bit rates as well as other selected attacks. The data payload is comparatively high compared to existing audio watermarking schemes