A Study On Quantum Image Steganography Algorithm Based On Gray Code Mapping And LSB

In recent years,with the rapid development of computer technology,people’s attention to information security has been increasing.Quantum image steganography technology utilizes the basic characteristics of quantum states to protect the security of images,thus becoming one of the hot topics of current attention.Quantum image steganography algorithms mainly focus on performance indicators such as embedding capacity,security,and robustness.Reviewing existing research results,it can be found that quantum image steganography algorithms still have shortcomings in embedding capacity and security.In response to the above issues,this article proposes two high-capacity color image quantum steganography schemes based on Gray code mapping and LSB(Least Significant Bit).The specific research content is as follows.1.Designed a quantum description method and quantum image scrambling method for color images.This paper improves the QRMW quantum representation model by constructing three balanced superposition states using two quantum bits and using them to represent RGB three channels of color images.Compared with existing methods,channel redundancy is eliminated.For the disadvantage of classical image scrambling methods that can only perform position scrambling,this paper proposes a quantum bit random flipping scrambling method based on pixel color value scrambling.This method can not only change the histogram of the image,improve the security of scrambling,but also enable rectangular images to be scrambled.2.A quantum image steganography scheme based on Gray code mapping and single-stage LSB is proposed.The scheme uses color image as the carrier,divides the scrambled secret information into 3 bit segments,and then embeds each segment of secret information into the LSB of the RGB channel of the carrier pixel based on the gray code rule to complete the information embedding process;Extraction is the inverse process of embedding.First,the secret information segment is extracted from the RGB channel of the carrier pixel,and then it is spliced and restored to the original secret information.Each carrier pixel can hold 3 bits of secret information and has high embedding capacity;The embedding rule based on Gray code effectively improves the security of the embedding scheme.3.A quantum image steganography scheme based on Gray code mapping and two-level LSB is proposed.The embedding capacity of this scheme is up to 6 bits per pixel.In this scheme,in order to ensure the security of the embedded information,the secret information is first scrambled,and then divided into 6 bit segments.Finally,the first three bits are embedded into the second LSB of the RGB channel of the carrier image using gray code rules,and the remaining three bits are embedded into the first LSB of the RGB channel of the carrier image.According to the embedding rules,the difference between the LSB of the steganographic image and the embedded secret bit is almost 50%,which further ensures the security of the embedded information.Extraction is the inverse process of embedding.In this thesis,a quantum circuit for related operations is designed.The simulation results on a classical computer show that the two schemes proposed in this thesis are not only superior to other similar schemes in terms of embedding capacity,but also have high security,which further proves the feasibility of using Gray code mapping and LSB to implement quantum steganography research scheme.