DIGITAL SIGNATURE CREATIONS BY USING DISCRETE COSINE AND WAVELET TRANSFORMATIONS

Abstract

The bringing on of digital signature (DS)–is a method of revealing unique owner sight and used first of all for identifications and protections copyrights.Depending on the method of data conversion, the technology of applying the DS can use spatial method, frequency method and spectral connections method. At present moment methods of DS constantly perfected. Int hisreport the applying of DS two algorithms are used-DCT and WLT Selection of algorithms depends from selections by users the types of DS. The DC being processed after selections, including transformations to the grayscale. For the realizations of  DCT the algorithms Hsu was used . This algorithm is used in the case, where DS is more than twice smaller from the document. For the realizations of wavelets transformations, Pitas algorithm was used. This algorithm is useful in the case of DS with size more than half of image value.

Key words: digital signature, discrete cosine transformations, discrete wavelet transformations, algorithms Hsu, Pitas algorithm