Digital Watermarking And Its Application In Still Images

Digital watermarking has recently been proposed as a new mean to provide copyright protection of multimedia data and image authentication. Discrete Cosine Transform and Wavelets are respectively the key technique in the subsistent source compression coding Standard JPEG and ongoing source compression Standard JPEG-2000, the applications of digital watermarking in still images systematically are discussed. two robust watermark schemes based on DCT domain and DWT domain are given separately ; both schemes used modular arithmetic , in embedding arithmetic had no use for original image ,experiment result indicated that both schemes are robust to JPEG compression, noise, and cropping ; a frail watermark based on DWT domain is also introduced , computer simulation indicates this scheme not only robust to JPEG compression and noise but sensitive to spitefully attack; image's attacking is discussed an attack scheme based on bit plane is given finally.