A survey of digital image watermarking techniques based on discrete cosine transform

In this study, a literature review is presented to examine the Discrete Cosine Transform (DCT) based digital image watermarking techniques since 2010. General features of the digital watermarking, frequency domain & spatial domain watermarking techniques, DCT and various watermarking researches with DCT in last decade were stated. The studies were classified according to the application methods of DCT, features of the watermarking technique, watermark extraction method, robustness, and usage area. Results have shown that DCT has increased the robustness of watermarking by performing with a union of several methods from simple to complex. In this case, the main purpose of this study can be considered as making a compilation of DCT techniques and preparing an information note that can be a reference for those working in this field. For the future studies to improve watermarking with DCT, a combination between machine learning and optimization techniques would be preferred. According to the obtained and collected knowhow, DCT was combined with Single Value Decomposition and Arnold Transformation which are transformations made in the spatial domain and a reversible digital image watermarking study was carried out with a secret key that was generated from Hash function. Then watermak techniques was examined with attack analysis. As a result of the study, it has been determined that the use of DCT with different transformations increases the robustness of the digital image watermarking.