Abstract

Due to rapid increase in digital data transmission over internet, information security becomes a vital issue. Audio steganography is one of the ways used for information security over the internet. In audio steganography, the secret data is transmitted with audio signal as the carrier. In this paper, an algorithm for hiding image data in an audio signal is proposed. The cover audio signal is transformed from time domain to wavelet domain using lifting wavelet transformation. Image is encrypted using Arnold transformation. Transformed image is then hidden in wavelet coefficients of cover audio. The quality of the resulting stego audio signal is tested by computing Squared Pearson Correlation Coefficient (SPCC) and SNR values. And the extracted image quality is tested by computing Peak Signal to Noise Ratio (PSNR), Structural Similarity Index Metric (SSIM) and Universal Image Quality Index (UIQI). Results show that stego audio is perceptually indistinguishable from the cover audio. Cover audio is robust even in presence of external noise. It provides high capacity, secure data extraction.