Review of the current methods for robust image hashing

The development of an Internet of things concept has led to an essential increase in the amount of data processed via the Internet. Multimedia data constitute a significant proportion of this information. This type of data often contains user’s personal information or copyright protected data. The issue of copyright protection of digital imagery has remained topical for the last decades. Traditional information protection tools cannot provide the required level of image protection from possible threats due to specific features of format representation. This article contains a comparative analysis of published research papers concerned with the robust image hashing as one of possible methods of copyright protection of digital imagery. It also includes a classification of robust image hashing methods, discussing their advantages and drawbacks, and their major characteristics. At the end of the article some directions of further research are outlined.