Image Information Hiding Program

With the network technique and digital multimedia technology development, the people's life gradually become digital and network, but people are suffering from information security while also enjoying the convenience. Compared With the traditional "passive" password protection technology, information hiding technology has the advantage. At home and abroad, the information hiding technology and information hiding detection technology have developed to a mature stage. There are many important applications, such is the copyright protection, information authentication, anti-counterfeiting mark, tamper with Prompt, secret communication etc all.This article main research direction is information hiding technology of digital image. This article systematically introduces research background and significance of the information hiding technology and developing situation of domestic and overseas, summarizing the basic principle of universal model, technical classification, technological characteristics and subjective and objective evaluation standard. Through the analysis of the space algorithms and transform algorithms, this article chose three existing algorithms and improved them, finally doing experiment:1. Proposed block LSB algorithm based on human visual system (HVS). Using the human vision characteristics, this algorithm sorted cover image into smooth area, border area and texture area with threshold and variance, embedding respectively 1 bit,2 bit and 3bit secret message in these three kinds block according JND (Just Noticeable Difference) threshold value. This algorithm ensures utterly embedding capacity and imperceptible.2. Through improving the traditional sub-affine transformation which is a image scramble method, the algorithm's security is to be higher. Use Logistic chaotic sequence for cover images and secret image fusion in order to achieve the purpose of large capacity information hiding.3. Decompose the cover image using integer lifting wavelet transform (IWT) while encode the secret image using reduced frequency. Using polymorphism embedded technology embed secret image's character encoding in the LH2 sub-image. Follow some certain criteria while choose embedded sub-band and set the value for the difference state division threshold which make the embedding algorithm followed the original digital image's features distribution.