A high quality image hiding scheme based upon noise visibility function and an optimal chaotic based encryption method

This paper presents a novel image steganographic approach for hiding a secret image in the cover image deals with improving both visual quality of the stego-image and the security of the secret image, while still providing a large embedding capacity. First, to improve both the visual quality and to keep the embedding capacity at an acceptable level, the payload of each region of the cover image is determined dynamically based on Noise Visibility Function (NVF). Second, to ensure the security of the secret image, an optimal chaotic based encryption method is generalized to transform the secret image into an encrypted image. Third, the optimal chaotic based encryption method is obtained by using GAiPSO algorithm to find an optimal secret key. The optimal secret key is able to encrypt the secret image in such a way that after embedding, the rate of changes in the stego-image can be decreased which result in increasing the quality of the stego-image. The experimental results demonstrate that the proposed scheme is able to achieve a good trade-off between the payload and the setgo-image quality.