A robust visual image encryption scheme based on controlled quantum walks

Considering that traditional cryptographic systems are under threat of quantum computing, a visual image encryption algorithm based on controlled quantum is proposed. First, the plaintext image is encrypted by compressed sensing, and the compressed image is scrambled using Arnold to obtain the secret image. Then the segmented secret image is embedded into the carrier image by singular value decomposition (SVD) in accordance with different intensities to generate images with visual significance. In order to make the algorithm more secure, the controlled quantum walk is used to generate pseudorandom sequence to construct the measurement matrix of compressed sensing and the position of the secret image embedded into the carrier image. In addition, the use of SVD embedding can make the plaintext image flexible to choose the carrier image.