Research On Self-adapting Watermaking For Color Image Based On Dct

In the latest several years,the sharp development of digital techniques and computer network gives the application of digital multimedia(digital images,digital audio,digital video and 3-D computer images)a stupendous development and bring along with our work and life great convenience.But just because of this,digital multimedia is very easy to be copied, jug gled,illegally diffused and purposive attacked.So,the problem of copy right protection to digital multimedia is being given more and more attention and digital watermarking technique is so far the most effective digital product copyright protection technique.In this paper,we primarily investigate and discuss the color image digital watermarking in this field.Starting from the basic conception and characters,this dissertation firstly analyzed the characters of Discrete Cosine Transform.On the basis of the above,an adaptive watermarking algorithm for color images based on DCT was proposed and the process of its generating,embedding,detecting and extracting were expatiated in detail.Experimental results show that the watermarking algorithm for colorful image is invisible and robust against various signal processing such as cropping,JPEG compression,filtering,noise adding,image enhance-ment and mosaic.