Research On Chaotic Encryption,Hiding And Lossless Extraction Algorithm Of Color QR Code

The rapid development of network transmission technology not only brings innovation to electronic technology and people's life,but also makes a qualitative leap in the speed of information transmission.However,the following information transmission security issues have also attracted much attention.Increasing the capacity of information hiding effectively and solving the problem of secure transmission of image secret information have become the research hotspot for scholars.At present,information hiding technology mainly focuses on text,binary image and gray image as secret information for hiding and extraction.Some scholars hide simple color images,but most of them are lossy extraction of secret information,and identify the extracted information by humans.Although the decoding of color QR(quick response)code requires high accuracy of color block,it has the characteristics of large capacity of encoded information,fast and objective reading information.With the development of research,color QR code will have a wide application prospect.Combined with the characteristics of color QR code,secret information is encoded to generate color QR code,which is encrypted and hidden in the color image to realize color QR code encryption,imperceptible hiding and lossless extraction.The main work is as follows:(1)In order to solve the problem of low hiding capacity of frequency domain information,secret information is encoded to generate color QR code,which is encrypted and hidden as secret image.The coding capacity and characteristics of color QR code are compared with traditional black and white QR codes.The features and advantages of color QR code as secret image hiding are analyzed and discussed.The combination of color QR code as secret image and information hiding technology is proposed to increase the information hiding capacity.(2)In order to solve the problem of small key space in traditional one-dimensional Logistic chaotic mapping encryption method,an improved one-dimensional Logistic chaotic image encryption algorithm is designed to ensure the information security of color QR code(color secret image).After the color secret image is encrypted by Arnold transform,the gray value of the scrambled image is encrypted by using the improved one-dimensional logistic chaos map.The improved one-dimensional logistic has a larger key space and better chaos effect than the classical one-dimensional logistic mapping.It has large key space,strong sensitivity to initial value,good encryption security.It can resist exhaustive type cracking and enhance the security of color secret image.(3)An information hiding algorithm for color QR code hiding and lossless extraction is proposed.This paper analyzes the color image hiding algorithm based on discrete cosine transform(DCT).The data type of DCT frequency domain transform information hiding is floating-point type.When the image is displayed and stored,the data type is integer type.In the process of data type conversion,the rounding error is generated,The rounding error data will also be hidden in the secret image,and used for error compensation when extracting the secret image,so as to improve the color image quality The accuracy of color image extraction.The algorithm can realize perceptual hiding and lossless extraction of color QR code,and provide a new idea for objective authentication of secret information.Moreover,the algorithm can be applied to ordinary secret color images.