Quantum image scaling with applications to image steganography and fusion

A quantum hue, saturation, and lightness model is proposed in which a triple qubit sequence (QHTS) is encoded and used as a data model for the implementation of quantum image scaling. The preparation and retrieval of QHTS images is presented, in which only q+2 qubits (where q is the bit depth) are required to encode color information while retaining relevant HSL image features and operability. A conventional nearest neighbor interpolation was adopted to implement quantum image up-scaling and down-scaling operations, from which two other scaling applications were developed. One such technique is a form of quantum steganography based on end-to-end encryption, which provides high capacity while ensuring the security of carrier images and secret messages. The other is a spatial remote sensing image fusion algorithm, based on QHTS images, which pioneers quantum pseudocolor composites of multi-spectral and panchromatic images. Simulation experiments demonstrated the proposed methodology provides an embedding capacity more than double that of existing quantum image steganography algorithms. In addition, a complexity analysis demonstrated the efficiency of the two proposed quantum image scaling applications, which take full advantage of quantum parallelism.