Background: The growth in the field of communication has enabled the people at miles apart to communicate easily.Once the online sharing of information is made possible.It is necessary to ensure about the security of the information that is shared.Materials and Methods: In this study, three levels of encryption process has been carried out.Quantum Key Distribution(QKD) with bit XOR forms the first level of encryption.Flipping and swapping of the ciphered block images were done using quantum walk principle forms the second and the third level of encryption.Results and Discussion: To prove the robustness of the proposed scheme, image encryption metrices like horizontal, vertical, diagonal correlations, No. of Pixel Change Rate (NPCR), Unified Average Changing Intensity(UACI) were estimated and compared with the available literature.Conclusion: The QKD and quantum walks forms the basic level of image encryption and offers NPCR 99.68 and UACI of 30.50.Flipping, swapping and bit XOR of the ciphered block images were done.To verify the robustness of the proposed method and the values are found to be better.
Background: The growth in the field of communication has enabled the people at miles apart to communicate easily.Once the online sharing of information is made possible.It is necessary to ensure about the security of the information that is shared.Materials and Methods: In this study, three levels of encryption process has been carried out.Quantum Key Distribution(QKD) with bit XOR forms the first level of encryption.Flipping and swapping of the ciphered block images were done using quantum walk principle forms the second and the third level of encryption.Results and Discussion: To prove the robustness of the proposed scheme, image encryption metrices like horizontal, vertical, diagonal correlations, No. of Pixel Change Rate (NPCR), Unified Average Changing Intensity(UACI) were estimated and compared with the available literature.Conclusion: The QKD and quantum walks forms the basic level of image encryption and offers NPCR 99.68 and UACI of 30.50.Flipping, swapping and bit XOR of the ciphered block images were done.To verify the robustness of the proposed method and the values are found to be better.
To secure and protect the photos from unfair tactics, the encryption process is used. the advent of the digital era has made it exceedingly easy to hack any data kept on the cloud. Encryption is critical to ensuring communication security, which is a crucial issue. There are numerous photo encryption methods that mostly rely on chaotic logistic maps; however, they have downsides such a small key space and low security. Current analysis introduced experimental results of quantum chaotic cryptosystem,3D-Chaotic map and quantum chaotic logistic map. This paper we measure image encryption parameters are Entropy, structural similarity index measure, combined average changing intensity and net pixel change rate which defines utilization of suitable image encryption approaches. For the cypher and the original image, we quantify the correlation coefficient value in both the horizontal and vertical positions with comparison of all three existing Approach-es performance. The scientific and practical economic results reveal that the quantum chaotic cryptosystem has outstanding performance and in future with utilization of advanced Approaches we can resist various cryptographic attacks.
This research introduces a novel cryptographic system that enhances the security of steganographic images by integrating Quantum Key Distribution (QKD) with traditional encryption. Using the E91 QKD protocol, it generates a shared secret key between parties, leveraging quantum entanglement to provide superior protection against eavesdropping. The quantum key is then hashed with the Secure Hash Algorithm (SHA) to produce a fixed-length, high-entropy key for symmetric encryption . The Advanced Encryption Standard (AES) is employed to encrypt steganographic images, which conceal critical data within digital images, adding an extra layer of security through obscurity. Experiments with images of varying resolutions (64 × 64 to 512 × 512 pixels) show consistent encryption performance. The encrypted images exhibit high randomness, with an average entropy of 7.9929. Differential attack resilience is demonstrated by a Number of Pixels Change Rate (NPCR) averaging 99.6928% and a Unified Average Changing Intensity (UACI) of 56.1549%. The average E91 protocol key generation time is 5.78 s with a key rate of 7.43 bps. Encryption and decryption times for test images are 0.00149 and 0.00175 s, respectively. This research combines quantum and classical cryptography with steganography, providing a robust security framework highly resistant to both quantum and classical threats.
Quantum image encryption (QIE) loads a digital image into qubits and ciphers it with unitary circuits, usually keyed by chaotic maps, quantum walks or quantum random numbers. This review follows the field from an early geometric-transformation scheme (2013) to designs executed on 127-qubit IBM processors (2025). We organise the literature by image representation (FRQI, NEQR, amplitude encoding), confusion and diffusion mechanism, key source and validation level, and we compare recent schemes on entropy, NPCR, UACI, correlation and key space. Reported statistics sit close to their ideals almost everywhere; recent quantum-walk and chaos-based designs report NPCR of 99.6 to 99.97% and UACI of 33.5 to 33.9%, so these metrics no longer separate strong schemes from weak ones. Three gaps stand out. Most evidence comes from classical simulation. The secret usually sits in a classical key generator rather than in the quantum circuit. And loading an image into qubits, then reading it back, remains the main hardware bottleneck. Hybrid designs that distribute keys with BB84 and cipher the image classically offer the most deployable route today. We close with a research agenda: attack-based benchmarks, error-aware hardware validation, cheaper state preparation and explicit security definitions.
In order to further improve the security and efficiency of quantum image encryption, a three-layer encryption scheme for quantum color images based on 6D hyperchaos is proposed for the improved quantum representation model. The sequences generated by the 6D hyperchaotic system are applied to each layer of image encryption as keys. First, the quantum Fibonacci matrix is used to scramble the pixel value positions of the image to achieve the spatial scrambling of the quantum image; then, the position exchange of red, green, and blue channels and the bit-level cycle shift of pixel value are carried out alternately to realize the bit-level scrambling of quantum images; Finally, the XOR operation is performed on the quantum image whose position has been scrambled to realize the bit-level diffusion of the quantum image and obtain the final encrypted image. Simulation results show that the encryption algorithm is highly sensitive to the initial key, and the pixel values of the encrypted image are evenly distributed. In addition, quantum circuits are designed to implement the image encryption steps of each layer.
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.
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.