Research On Steganography Based On Local Distortion Function Design

Steganography can hide secret information in cover and transmit stego through the common channel,so that both sides of the communication can achieve secret communication.As an important branch in the field of information hiding,steganography is highly valued and studied by many scholars in the field of information security due to its good confidentiality.Nowadays,the key problem in the field of steganography is to design a steganography algorithm with various forms,high information embedding rate and high security.In this thesis,two different designs of steganography are proposed under the existing framework of minimum embedded distortion.The main works are as follows.Aiming at the problem that using the additive distortion design cost function will affect the security of the steganography algorithm,a scheme for using Daubechies wavelet to enhance steganography security is proposed.The advantages of Daubechies wavelet in image processing are combined with WOW steganography algorithm framework.Average filter is used to deal with noise and enhance the correlation of pixels.On the BOSSbass1.01 image database,an integrated classifier was used to classify the SRM features and SRMQ1 features of the cover and stego to test the security of the steganographic scheme.Experimental results show that the proposed steganography scheme is much safer than the mainstream steganography algorithms.Aiming at the problem that the steganographic analyzer will focus on detecting complex areas of texture,a steganography scheme using RGB color channel differences is proposed.From the perspective of RGB color space,controversial pixels are defined in the way of statistical differences between different color channels,and the value of the image is weighted and redistributed,and secret information is embedded in the cover according to the value of the generation after the smooth processing by combining the Syndrome-Trellis coding scheme.2044 images were extracted from the NRCS image library,UCID image library and the standard image library of the university of Washington to form an experimental database for the security detection of steganography algorithm.Through comparison with the security of mainstream steganography algorithm,it was found that the proposed steganography scheme can greatly improve the security of steganographic algorithm.