An imperceptible spatial domain color image watermarking scheme

Abstract

The paper proposes a novel scheme for color image watermarking. Spatial domain techniques are used here for embedding the watermark information to generate high quality watermarked image. Spatial domain methods are popular with fragile watermarking techniques that mostly use two or three least significant image bits for storing the recovery information. Here spatial domain methods are further explored to develop a robust mechanism for copyright protection. The method presented gradually spreads the watermark information over a region of pixels as implemented by the transform domain techniques. Thus the method is designed to deliver the two essential features required of watermarking systems namely, high image quality and high robustness to attacks. Also after watermark embedding it is ensured that the alterations in one color component are well compensated and no color difference or variations is visually evident. For watermark embedding and color compensation two masks are proposed. The algorithm is experimentally analyzed using various quality metrics and watermark removal attacks. The results prove the model support imperceptible watermarking and high resilience to attacks. Keywords: Color image watermarking, Spatial domain, Watermark, Embedding, Extraction, Attacks