In view of the limitations of existing image encryption technique and high security of quantum key distribution scheme, an image encryption algorithm based on six-state quantum key distribution scheme is proposed. On the basis of two groups of conjugate bases of four states scheme(BB84 protocol), another pair of rotating measuring bases are introduced to constitute six state base space; random binary key strings are generated with six-state scheme, then the key strings and image data are operated with XOR, and image data are replaced with the operation results. Experimental results and security analysis show that with the new algorithm key space increased, the brute force attack can be resisted; with lower relevancy of plaintext and cipher text, the chosenplaintext attack can be effectively resisted; the algorithm achieves better sensitivity and security.
In view of the limitations of existing image encryption technique and high security of quantum key distribution scheme, an image encryption algorithm based on six-state quantum key distribution scheme is proposed. On the basis of two groups of conjugate bases of four states scheme(BB84 protocol), another pair of rotating measuring bases are introduced to constitute six state base space; random binary key strings are generated with six-state scheme, then the key strings and image data are operated with XOR, and image data are replaced with the operation results. Experimental results and security analysis show that with the new algorithm key space increased, the brute force attack can be resisted; with lower relevancy of plaintext and cipher text, the chosenplaintext attack can be effectively resisted; the algorithm achieves better sensitivity and security.
In this paper, a quantum image encryption scheme is proposed by using the inter–intra bit-level permutation strategy. The image to be encrypted is first represented by a novel enhanced quantum representation model, and then, the intra and inter permutation operations are successively performed on bit planes. The intra bit permutation is achieved by sorting chaotic sequence, and the inter bit permutation is accomplished with qubit XOR operations between the two selected bit planes. The ciphertext image is finally obtained through a chaotic diffusion procedure implemented with a quantum image XOR operation. The XOR operation is realized by controlled- NOT gates, which is controlled by a chaotic sequence generated with a logistic map. The parameters of the logistic map are sensitive, which makes the key space large enough to resist brute-force attack. The proposed scheme not only modifies the pixel positions and gray values but also makes the bit distribution more uniform. The quantum circuits for the proposed encryption algorithm are devised. The simulation results and theoretical analysis show that the proposed method is more efficient than its classical counterpart, and its security is verified by the statistical analysis, keys sensitivity, and key space analysis.
Given the limitations of current classic image encryption algorithms and the unconditional security characteristics of quantum key distribution protocols, the author proposes an image encryption method based on quantum key distribution and pixel scrambling. The author first analyzed the security issues of quantum image encryption algorithms based on image scrambling methods, namely that image scrambling methods have periodicity, which can ensure that the image can be restored after scrambling. If an image cannot be guaranteed to return to its original state after performing scrambling operations, legitimate users cannot obtain the secret information in the original image, and image scrambling loses its original meaning; However, the periodicity of image scrambling methods not only ensures that legitimate users can decrypt images, but also provides convenience for attackers to steal original image information. Secondly, it is pointed out that when evaluating and analyzing quantum image encryption algorithms, the evaluation indicators should include two parts: One is performance analysis, which is the analysis of the network complexity of quantum circuits. In quantum computing, the network complexity of quantum circuits is usually represented by the number of quantum basic logic gates. The second is security analysis, which mainly includes key analysis (including key space size and key sensitivity analysis), statistical analysis (including pixel correlation, histogram analysis, information fusion, and scatter plot distribution density analysis). Finally, experimental simulations have shown that the NPCR values of the plaintext and ciphertext images of the three images tend to 100%. The encrypted image histogram is evenly distributed, with very weak pixel correlation and high pixel change rate and information entropy.
In order to improve the security of traditional encryption systems, hyper-chaotic systems are introduced into the field of quantum image encryption. Firstly, the image is bitwise XOR by He fractional order hyper-chaotic Rabinovich system, and then the color image is represented as a quantum superposition state. The quantum image is scrambled by the unitary matrix generated by Logistic hyper-chaotic sequence, and then a hyper-chaotic sequence is generated to randomly replace the red, green and blue primary colors of each pixel to achieve the purpose of quantum image encryption. Finally, numerical simulation experiments are carried out on a computer. The experimental results show that the histogram of the encrypted image is flatter and even, the pixels are evenly distributed between 0 and 255, the correlation between adjacent pixels of the image is low. The average correlation coefficients of the red, green, and blue pixels of the encrypted image are 0.0012, 0.0025, and 0.0018. The system has high key sensitivity and can effectively resist statistical analysis attacks. The algorithm has good security and robustness.
Secure image transmission is increasingly vital in the digital era, especially against emerging quantum threats. This study proposes a hybrid image encryption scheme that integrates Quantum Key Distribution (QKD) using the BB84 protocol with a combination of 7-dimensional (7D) and 2-dimensional (2D) hyperchaotic systems to achieve robust security. The BB84 protocol facilitates quantum-assisted key exchange, ensuring resistance to eavesdropping, while the hyperchaotic systems provide high entropy and complex randomness, utilized in a layered permutation-substitution encryption framework. The initial seeds for chaotic sequences are derived using a SHA-512 hash of both the input image and quantum-generated key, ensuring uniqueness and sensitivity. Experimental validation was conducted using several benchmark images. The information entropy values of the ciphered images reached up to 7.9993, indicating excellent randomness. Differential analysis showed high resistance to small perturbations, with NPCR exceeding 99.61% and UACI averaging around 33.47%, which meet standard security thresholds. Histogram and chi-square tests confirmed the uniform pixel distribution, with chi-square values below 280, satisfying the randomness criterion for 8-bit images. Furthermore, correlation coefficients of adjacent pixels dropped to near zero, evidencing effective decorrelation. The encryption scheme also demonstrated robustness to data loss, as shown by the successful decryption of partially corrupted cipher images. Robustness testing under partial data loss (200×200-pixel blocks) also demonstrated visual recoverability and algorithm resilience. Overall, the proposed BB84-assisted dual-hyperchaotic encryption scheme offers a secure and computationally effective solution for protecting sensitive image data, making it suitable for post-quantum secure communications.
Abstract Quantum Key Distribution (QKD) is one type of Quantum Cryptography (QC) which is based on quantum mechanics fundamentals such as Heisenberg’s uncertainty principle and No-cloning theory. The usage of QKD warns the legitimate communicated parties to any attack attempt and this is the most interesting security parameter. Therefore, QKD provides unconditional secure communication method and supports a powerful encryption scheme. The combination between classical communication and QKD creates a new technique called semi quantum key distribution SQKD. Unfortunately, SQKD increases the schemes complexity and requires two steps for ciphering, scramble and encryption. In this paper an enhance image encryption algorithm is proposed based on QKD that eliminates most of the drawbacks of SQKD. The proposed algorithm is simpler than other encryption schemes as it exploits only one encryption step based on the power and the randomness of the generated secret key, which decreases the chance to be cracked. The correctness and efficiency of the proposed algorithm are validated by numerical simulations.
In the digital era, the security of image data has become increasingly important. This study aims to develop an image encryption scheme based on Quantum Key Distribution (QKD) and Fractional Fourier Transform (FRFT) to enhance the security of image data transmission and storage. The proposed scheme first utilizes QKD to generate and distribute secure encryption keys, ensuring the unconditional security of the key distribution process. Subsequently, FRFT is employed to perform complex transformations on the image data, using fractional order parameters to achieve multi-scale representation of the image in both time and frequency domains, thereby increasing the complexity and security of the encryption process. Experimental results demonstrate that this scheme exhibits significant advantages in terms of the quality of encrypted images and their resistance to attacks. Specifically, the encrypted images possess high Peak Signal-to-Noise Ratio (PSNR) and Structural Similarity Index (SSIM), effectively resisting various attacks. Comparative analysis further verifies the superiority of this scheme in terms of security and efficiency. In summary, the proposed combination of QKD and FRFT for image encryption holds great potential and research value in the protection of image data.