Invisible Watermarking Based on Creation and Robust Insertion-Extraction of Image Adaptive Watermarks
Principal Investigator: Bharat Bhargava
This paper presents a novel invisible robust watermarking scheme for embedding and extracting a digital watermark in an image. The novelty lies in determining a perceptually important sub-image in the host image. Invisible insertion of the watermark is performed in the most significant region of the host image such that tampering of that portion with an intention to remove or destroy will degrade the esthetic quality and value of the image. One feature of the algorithm is that this sub-image is used as a region of interest for the watermarking process and eliminates the chance of watermark removal. Another feature of the algorithm is the creation of a compound watermark using the input user watermark (logo) and attributes of the host image. This facilitates the homogeneous fusion of a watermark with the cover image, preserves the quality of the host image, and allows robust insertion-extraction. Watermark creation consists of two distinct phases. During the 1st phase, a statistical image is synthesized from a perceptually important sub-image of the image. A compound watermark is created by embedding a watermark (logo) into the statistical synthetic image by using a visible watermarking technique. This compound watermark is invisibly embedded into the important block of the host image. The authentication process involves extraction of the perceptive logo as well statistical testing for two-layer evidence. Results using standard benchmarks demonstrates the robustness and efficacy of the proposed watermarking approach. Ownership proof could be established under various hostile attacks.
Students: S. P. Mohanty
Keywords: authenticity, image, security, watermark