Adaptive Image Steganography: A Review and Research Directions

Steganography involves concealing secret information in an appropriate multimedia carrier, such as text, image, audio, and video files, in such a way that only the sender and receiver suspect the existence of the secret information. Images are the most popular multimedia carriers. Adaptive image steganography is a promising new trend in the steganographic field. It basically means that the embedding locations are altered adaptively depending on the image content. The primary objective of this paper is to investigate and discuss various approaches to adaptive image steganography. The approaches can be broadly categorized as CNN-based, end_to_end GAN-based, and minimizing additive distortion function-based, both huristically and automatically designed. In addition to discussing the four categorized approaches, this paper provides an overview of image steganography including its characteristics or properties, and evaluation metrics. A summary table of all the details is also provided for convenience. The purpose of this paper is to assist fellow researchers by compiling current trends, their advantages and disadvantages, and identifying improvement gaps