Enhancing the Hiding Capacity of Audio Steganography Based on Block Mapping

With the rapid growth in exchanging personal and confidential data through an unsecure channel like the internet and exposing it though disclosing by intruders, the necessity of information security became a great demand. As a result, data hiding or steganography appeared as a vital solution. Audio hiding is a concept of injecting the secret data in an audio carrier. This paper proposes a scheme known as ECA-BM, to improve the performance of the audio steganography. ECA-BM contributes in: (1) increases the hiding capacity, (2) maintains the transparency of carrier and (3) enhance the security of the proposed model. To increase the hiding capacity, fractal coding is adopted to create a mapping between the cover and secret blocks in order to encode the secret data into a set of coefficients with minimum size. To maintain the fidelity of the stego file, only 1-LSB from each cover sample is used for embedding. To increase the security of the ECA-BM, the cover samples for embedding are selected in a chaotic manner. LSB technique is utilized for embedding after converting secret coefficients into a binary sequence. Objective metrics, SNR, HC, and NC is used to evaluate the performance of ECA-BM. The Experimental results show a significant increase in the hiding capacity compared with some related studies. Moreover, the fidelity of the stego and reconstructed secret file are preserved.