WATERMARKING SCHEMES FOR COPY PROTECTION : A SURVEY

DIGITAL WATERMARKING IS THE PROCESS OF EMBEDDING INFORMATION INTO A DIGITAL SIGNAL, I.E. AUDIO , PICTURES , VIDEO , ETC . EMBEDDED MARKS IN THE MESSAGE ARE GENERALLY IMPERCEPTIBLE BUT CAN BE DETECTED OR EXTRACTED. THE EMBEDDING TAKES PLACE BY MANIPULATING THE CONTENT OF THE DIGITAL DATA , WHICH MEANS THE INFORMATION IS NOT EMBEDDED IN THE FRAME AROUND THE DATA . IF THE SIGNAL IS COPIED , THEN THE EMBEDDED INFORMATION IS ALSO IN THE COPY . BY IMPERCEPTIBLY HIDING INFORMATION INTO THE VIDEO CONTENT IT WILL BE POSSIBLE TO PREVENT COPYING OR PLAYBACK OF SUCH CONTENT . SO , WATERMARKING IS AN EMERGING TECHNOLOGY THAT IS CLAIMED TO HAVE AN IMPORTANT APPLICATION IN COPY PROTECTION . A VARIETY OF WATERMARKING TECHNIQUES HAVE BEEN PROPOSED BY RESEARCHERS FOR THE COPY -PROTECTION . THIS PAPER PRESENTS AN EXTENSIVE REVIEW OF THE PREVAILING LITERATURE IN WATERMARKING FOR COPY PROTECTION .