A Review of Digital Image Watermarking Techniques for Secure Data Transmission

Nowad a y s, a c h ief problem encountered by content provide r s and owners i s t h e p r otec t ion of their m aterial. The e a se b y which d i gital in f or m ation c a n be duplicated and distributed has led to the need for effective c o p y right protection tool s . Re c e ntly digital watermarking technology has e m erged a s an e f f e ct i ve s o lution for prot e cting the digital c o nte n t fr o m u n a uthorized c op y ing.  With its area of application coexisting in all three forms of media, i.e., image, music and video, the process of watermarking is as widespread as any digital media. Watermarking can be defined as the practice of perceptibly or imperceptibly altering a given work to embed a message about that work. This paper surveys the features and concepts pertaining to the two popular watermarking algorithm types, i.e., A) Spatial based techniques (under which we analyzes Least Significant Bit (LSB ) modification, correlation based and  Code-Division Multiple Access ( CDMA ) based techniques) and B) Transform based techniques (DCT and DWT based techniques).