Quantum-inspired video encryption for real-time surveillance using continued fractions and coset graph permutation

This research proposes a video encryption system based on quantum principles that integrates number-theoretic key generation along with algebraic permutation of a graph, and quantum gate-based substitution to secure an actual time stream of multimedia data. A 16 [Formula: see text] 16 key matrix is created through the employment of continued fractions of irrational numbers to yield a key with high entropy by enjoying a plethora of possible generated key values to prevent two keys from ever equating. The key matrix is algebraically permutated through a coset graph traversal constructed from group theory, to yield organized, but random key scrambling impact on the indexed values. A substitution step is suggested in the algorithm by employing transformations reminiscent of quantum gates that introduce added randomness into the bits and destroy correlation. The process of encryption is carried out through a series of substitution and permutation steps to produce cipher frames that yield statistically uniform intensity distributions with low correlation between frames. Experimental analysis conducted on thermal video datasets indicates almost flat histograms, entropy values close to the theoretical value of 8, correlation coefficients close to zero, NPCR 99.6%, and UACI 33.2%. Encryption of a frame occurs in an average of 0.0632 s per frame and is with uniform spatial complexity, making the proposed scheme an effective, mathematically sound approach for secure video surveillance applications demanding lightweight, real-time encryption.