Mitigation of Geometrical Attack in Digital Image Watermarking using Different Transform Based Functions

The illegal act of digital multimedia data loss the value of information and integrity. The loss of information and integrity born the process of piracy of digital data. The piracy of digital data loss the brand value of documents and products. For the prevention of piracy used the digital watermarking technique. The digital watermarking techniques provide copyright protection and increase the value of brands — Watermarking techniques used in various fields such as image, video, audio, and text. The process of watermarking techniques proceeds in two manners spatial domain and frequency domain. The processing of frequency based watermarking techniques is roughest and fast processing of watermarking. Now in the current scenario, various transform function is used for the embedding process of watermarking techniques. In this approach present the studied of digital watermarking techniques based-on different transform function such as DCT, DWT, FFT, and many more transform function. The transform function based watermarking techniques faced a problem of geometrical attack. The Geometrical attack deforms the watermark and gets information. The prevention of watermarking techniques against the Geometrical attacks is a big challenge for the researcher in the field of digital watermarking.