Research of possibility of improvement of realization of algorithm of method of koch for embedding of digital watermarks in images

Abstract

In a modern information society the problem of the control of use of the property rights to digital information resources becomes more and more actual. One of the most effective ways of the decision of this problem is use of digital watermarks - digital labels, not visible without the special software and a confidential key. A digital watermark - the technology created for protection of copyrights to multimedia files. It can be the text or a logo unequivocally identifying the author of a file. Digital watermarks are applied in coding and decoding of the acoustic information, in technologies of search and definition of illegal copies of audio materials. In the given work research of algorithms of embedding of digital watermarks in images was conducted. In practice more often the others for embedding of digital watermarks in images are used by the algorithms based on discrete cosine transformation. In article research which allows to conclude is resulted that the method of Koch is the most effective for protection of copyrights by introduction digital watermarks in the image. The analysis of lacks of a method is carried out. Owing to double application discrete cosine transformation to the image at introduction and extraction digital watermarks, and also applications of the return discrete cosine transformation for return to integer matrixes of pixels after introduction the parity of factors of a frequency matrix can be broken, and it is inadmissible, as the result of work of algorithm directly depends on it. Avoid occurrence of the given problem during embedding of bit digital watermarks it is offered to spend correction of values of factors of a frequency matrix. The algorithm of realization of a method of Koch is resulted and its modernization for embedding of digital watermarks is proved. The way and algorithm of return transformation is described. Results of research about dependence of value of factor of force of embedding ε from brightness of the image-container and built in digital watermark are resulted the size.

Keywords

• digital watermark, discrete cosine transformation, a method of Koch.