Aggregation of Discrete Cosine Transform Digital Image Watermarking with Advanced Encryption Standard Technique

Signal is a function of one or more independent variables which contain some information. Signals are of different category depending upon their characteristics. They are classified as noise signal, deterministic signal, random signal, periodic signal, non-periodic signal, physically realizable and non-realizable, energy and power signals, analog and digital signals, etc. The Information carry by these signals are in different formats like text, image, audio, video, etc. Due to advance internet technology, it is very easy to transfer data from source to destination within second. Thus, issue of security and copyright protection of data increases. There are different methods and techniques used for providing security and copyright protection used for data. In this research, aggregation of two techniques i.e. 2D-DCT based digital watermarking for copyright protection and AES technique using 256 bits key for security of digital image against different attacks like as jpeg compression, salt pepper noise, gaussian noise, median filter, cropping, etc.