NETWORK CAMERA APPARATUS, NETWORK CAMERA SERVER AND DIGITAL VIDEO RECORDER FOR PREVENTING FORGERY AND ALTERATION OF A DIGITAL IMAGE, AND APPARATUS FOR AUTHENTICATING THE DIGITAL IMAGE FROM SAID APPARATUS, AND METHOD THEREOF

摘要

The present invention discloses a network camera apparatus, network camera server and digital video recorder which makes it possible to prevent a digital image from being forged or altered by embedding a watermark into an image signal input through a camera in a real time. Two types of watermark, i.e. a robust watermark for authenticating whether the image is original image or not and a fragile watermark whether the image is forged or altered or where the forgery or alteration of image takes place. An authentication apparatus for authenticating the watermark-embedded image is further disclosed.