| Recently, the development of multimedia storage and transmission technology,especially the popularization of the Internet technology push the development of the digital media application,Many types of multimedia works such as image,video and music can be conveyed in a new way of network.These technologies bring people many conveniences,but they also bring us some large side effects,for example,anybody can get the original products of others easily, especially digital products such as images,musics,films. Someone can copy and tamper the original works arbitrarily under disagree,as infringes the author's copyright. How to protect the copyright effectively and solve the problem of information safeties on network is a urgent subject.Under this condition, as a kind of technology to solve multimedia information security problem on network, watermarking technology comes up into being.It embeds watermarks into the digital medias,then carries out the functions such as informations hiding,storing, copyright safeguarding by tracking the use of the image by detecting the watermarks.At present,watermark technology becomes a kind of effective means to multimedia copyright authentication and its integrity safeguarding.This paper takes still images as example,firstly researches the urgent problems of the watermark technology, it brings present popular image process technology into watermark technology in succession(such as DCT,DWT ,fractal technology).It firstly innovates a watermark scheme based on fractal transform,and studies the zero-watermark technology. The main contents are described as followed:1. makes general analysis and research on Human Visual SystemThe characteristicness of Human Visual System is the process being considered firstly for every image process technology,include watermark technology,In order to join the characteristicness of HVS and the watermark technology together,this paper analyses and researches the HVS theoretics particularly firstly.It build the aesthesia models and the JND models after discussing eyes' biology configuration particularly and expatiating eyes' aesthesia process.These works provide the foundation for the later research of watermarkchannel capacity and the watetmark embedding intensity.2. Researches the basis watermark managing works particularly and systemly. There are many works to do on watermak technology except watermarkembedding and extraction arithmetics such as the watermark choosing, encoding, modulating, demodulating and the watermark capacity.These prior and ultimate works ensure that the arithmetic is brought into effect.Just understanding these,this paper analyses and researches the basic watermark theoretics in many pages.It brings forward chaos modulation on watermark modulating, brings forward Chaos permuting on image permuting, introduces BCH encoding on letter watermark processing and discusses the approximate estimate of the watermark capacity in DCT domain and DWT domain by applying the current communication theoretics.There works not only extend ways for the later work but also are significative on watermark research.3. Brings forward a watermark method based on fractal theoreticsThis paper has a novelty that joins the fractal technology,DCT and DWT transform,watermark technology together.Fractal technology has strong vitality on the image encoding.DCT and DWT transforms have broad applications on the image process. So this paper introduces fractal technology into watermark technology, brings forward fractal watermark technology in DCT and DWT domain and tests the fractal watermark technology by many tests.Fractal technology is a new thought and solved scheme without doubt.4. Bring forward a now zero-watermark technology and scheme in the DWT domain.This paper changes the traditional and common scheme that embeds watermark into original image and brings forward a new zero-watermark technology.This method starts from the motive of watermark to solves the image authenticate problem without embedding any data into image.It not...
|
PDF Full Text Request