Oblivious fragile watermarking scheme for image authentication

An efficient fragile watermarking scheme intended for image authentication and integrity verification is proposed in this work. To watermark the underlying image, the gray scale of each pixel is adjusted by an imperceptible quantity according to the consistency between a key-dependent binary watermark bit and the parity of a bit stream converted from the gray scales of a secrete neighborhood of the pixel. To counter “collage” and “look-up table inferring” attacks, the scanning / watermarking order of the pixels follows a zig-zag path and the secrete neighborhood of a pixel is formed by picking previously watermarked pixels before the current pixel on the scanning path.