Research Of Digital Image Watermarking Based On Wavelet Lifting Scheme

With the development of information technology, the simple safe precaution that relied onthe traditional cryptography theory to carry on information can't already meet demands ofsociety . Shield by the normal multimedia files (such as image , video , audio), the transmissionhiding the secret file and carrying on information becomes an important developing direction.The technology of watermark relative to copyright protection, it is an information hiddentechnology that demanded blindly drawn, large capacity and good imperceptibility. Seeingthat image compress field at present, JPEG2000 have an extensive application prospect, this textpropose one image digital watermark technology based on JPEG2000 standard.Thesis analyses characteristic of Wavelet Lifting Scheme and the putting haphazardpretreatment impacts on image DWT coefficient under JPEG2000 standard, according to theanalysis results, have proposed the watermark embedded algorithm. This algorithm combines theWavelet Lifting Scheme and characteristic of human eye vision system (HVS ), through puttingthe haphazard pretreatment to the primitive figure, changes its DWT energy distribution , thenembeds watermark data by means-quantization to its low frequency affiliated terrain. Thismethod has the watermark demands of intangiblity and robustness at the same time , and has thecapacity of larger data. On this foundation, the article improves the embedded tactics further,expands embedded range of watermark, improves the data capacity of carrier , makes theembedded amount of the data reach a satisfied degree under attacking condition.The artificialresult indicates , the algorithm has a large data capacity and intangibility, can resist the attackthat has no intention , has realized the re-set target. At the same time the Algorithm is proposedbased on JPEG2000 standard, with the application of JPEG2000 compression form ,it has abetter applied cost.