Chaos-based image hiding scheme between silent intervals of high quality audio signals using feature extraction and image bits spreading

Audio steganography is the science of hiding data in audio files such that it becomes undetectable to any third party except the sender and the receiver. High quality audio files refer to files that are compressed but in a way that (in theory) no information is lost like the format used on Audio CD's and FLAC files (Free Lossless Audio Codec), so it is considered the best way to represent music rather than compressed and processed files when the use of bandwidth is not restricted. In this paper, a new technique for image hiding in high bitrate audio files is presented. The proposed method depends on hiding data within silent intervals of audio signal by changing their sample values according to a specific thresholding criterion without a great effect on the main audio file. The silent intervals are extracted using two simple and effective features, namely signal energy and spectral centroid. For increasing robustness, image bits are encrypted using hopping between several chaotic maps, and then encrypted image bits are spread and hidden in specific embedding positions using chaotic map random sequence. Experimental results show that the proposed method has high transparency, robustness and inaudibility.