Based on the Flexible Representation for Quantum Image(FRQI),a secure quantum watermark protocol is proposed.The new protocol is enhanced in invisibility by making full use of continued-fraction algorithm.It is impossible for anyone except the copyrighter to extract and recover the water image during the protocol execution,which ensures the security of the watermark image,while also providing effective copyright certificate.Simulation results show that compared with the traditional watermark protocol,the size of watermark image reaches the maximum value and the capacity of the new protocol is expanded to eight times that of the previous protocols,and it can better measure the performance of the computation load that is executed by the protocol.
Based on the Flexible Representation for Quantum Image(FRQI),a secure quantum watermark protocol is proposed.The new protocol is enhanced in invisibility by making full use of continued-fraction algorithm.It is impossible for anyone except the copyrighter to extract and recover the water image during the protocol execution,which ensures the security of the watermark image,while also providing effective copyright certificate.Simulation results show that compared with the traditional watermark protocol,the size of watermark image reaches the maximum value and the capacity of the new protocol is expanded to eight times that of the previous protocols,and it can better measure the performance of the computation load that is executed by the protocol.
A universal watermarking protocol for quantum images is designed in this paper. The protocol is developed based on quantum transform (QT) and quantum add operation (QAO). Moreover, a dynamic vector is introduced to control the embedding strength in the embedding process, which is obtained through the constraint that quantum image state should keep normalized in the entire computation process. Therefore, the dynamic vector is an optimal solution of an optimization equation, which makes the watermarked image with better visual quality. Compared with the other protocols or schemes, the proposed one can improve watermarking performance of visual quality and capacity. Experiments based on flexible representation of quantum image (FRQI) and Quantum Fourier transform (QFT) illustrate the superior effectiveness of the proposed protocol.
With the development of Globe Energy Internet, quantum steganography has been used for information hiding to improve copyright protection. Based on secure quantum communication protocol, and flexible steganography, secret information is embedded in quantum images in covert communication. Under the premise of guaranteeing the quality of the quantum image, the secret information is transmitted safely with virtue of good imperceptibility. A novel quantum watermark algorithm is proposed in the paper, based on the shared group key value of the communication parties and the transmission of the selected carrier map pixel gray higher than 8 bits. According to the shared group key value of the communication parties, the two effective Bell state qubits of the carried quantum streak image are replaced with secret information. Compared with the existing algorithms, the new algorithm improves the robustness of the secret information itself and the execution efficiency of its embedding and extraction. Experimental simulation and performance analysis also show that the novel algorithm has an excellent performance in transparency, robustness and embedded capacity.
Most of the studied quantum encryption algorithms are based on square images. In this paper, based on the improved novel quantum representation of color digital images model (INCQI), a quantum color image watermarking scheme is proposed. First, INCQI improved from NCQI is used to represent the carrier and watermark images with the size [Formula: see text] and [Formula: see text], respectively. Secondly, before embedding, the watermarking needs to be preprocessed. That is, the watermark image with the size of [Formula: see text] with 24-qubits color information is disordered by the fast bit-plane scramble algorithm, and then further expanded to an image with the size [Formula: see text] with 6-qubits pixel information by the nearest-neighbor interpolation method. Finally, the dual embedded algorithm is executed and a key image with 3-qubits information is generated for retrieving the original watermark image. The extraction process of the watermark image is the inverse process of its embedding, including inverse embedding, inverse expand and inverse scrambling operations. To show that our method has a better performance in visual quality and histogram graph, a simulation of different carrier and watermark images are conducted on the classical computer’s MATLAB.
Quantum watermarking technology, which is used in anti-counterfeiting and copyright protection, play an important role in the future quantum computer era. To embed more data and reduce image distortion, a novel quantum watermarking method of combining spatial domain and frequency domain is proposed. To this end, the carrier and watermark image are prepared by the novel quantum model of color digital images. The proposed quantum watermarking method is divided into two parts according to the needs of the owner and the importance of the watermarks. These two parts of watermark are embedded into the cover using the spatial and frequency domain. Analysis indicates that the complexity of the watermark separation process increases the difficulty for the attacker to reconstruct the quantum watermarking. Numerical simulation results using MATLAB software shows that this algorithm has better embedding capacity. Not only that, it also has good invisibility and can ensure the security.
Quantum watermarking technology embeds invisible watermark images into carrier images to mark ownership, which has broad application prospects. In the paper, with using the novel enhanced quantum representation (NEQR) of the image, a quantum watermarking scheme based on a novel space geometric transformation and Fibonacci scrambling is proposed. Combined with the Quantum Majority Finder (QMF) method, the watermark information is embedded into various positions of the carrier image. The Fibonacci scrambling disperses the pixel information of the watermark image into the entire image range, and the space geometric transformation rearranges the individual watermark pixel information. These methods improve the robustness and security of watermarked images against noise and cropping attacks and ensure the watermark's visual invisibility. Applying simulation experiments, these quantum processes are implemented on a classical computer. The visual quality quantified by Peak Signal-to-Noise Ratio (PSNR) and robustness of the proposed method are analyzed. Our watermarking scheme has good visual quality, and the PSNR of the watermarked image is approximately 45. Compared to existing methods, our scheme exhibits robustness to resist noise and cropping attacks. Especially in large-scale cropping, the proposed scheme has excellent advantage. Experiment results verify the effectiveness and superiority of the proposed scheme and provide new ideas and methods for developing quantum watermarking technology.
Quantum image watermarking technology is influenced by embedding algorithm, which permanently distorts the embedded quantum carrier image.To protect and authenticate quantum images without damaging the carrier images, this study proposed a quantum image reversible watermarking algorithm combining the most significant qubit (MSQb) and the least significant qubit (LSQb).First, a binary watermark image, a grayscale carrier image, and an empty key image were represented using the novel enhanced quantum representation of digital images.Second, the encrypted qubit of the binary watermark image was matched with the MSQb of the carrier image.If they were equal, then the high qubit of the quantum key image was flipped.Otherwise, the encrypted qubit of the binary watermark image was matched with the XOR value of the lowest two qubits of the carrier image.The LSQb of the carrier image was modified according to the matching result.Finally, the quantum watermarked image was obtained.Simulation experiments and theoretical analysis verified the feasibility and watermark performance of the scheme.Results demonstrate that the scheme achieves correct extraction of quantum image watermark and lossless restoration of original image.The visual quality PSNR of the carrier image embedded with watermark through the scheme is improved by approximately 4% compared with that through the traditional LSQb method.The study provides a reference for studying and implementing reversible image watermarking technology in the era of quantum computer, which can be applied to harsh copyright protection and authentication of the visual quality of the original carrier image.