Double-image encryption by utilizing the Fourier domain, singular value decomposition, chaotic phase mask and wavelet transform
Kapil Shankar Gaur, Hukum Singh, Seema Thakran, Kehar Singh · Journal of Modern Optics · 2025
This paper introduces a double-image asymmetric cryptosystem by employing singular value decomposition (SVD), chaotic phase mask (CPM) and discrete wavelet transform (DWT). The system has six keys, of which four keys are image-dependent (two for each image), while the other two keys are combined keys. One of the combined keys is generated using the CPM, and the other is obtained by the DWT operation. The DWT used in the cryptosystem decomposes the image into four components. The proposed cryptosystem is designed in such a way that both images require their own two separate private keys, and two combined keys to decipher the ciphertext. As both images have the same ciphertext, our cryptosystem is useful for addressing the storage challenges of the encrypted images. The efficacy of the system is proved by numerical simulations performed on MATLAB (R2022a) to calculate the evaluation metrics.