A novel robust approach for image copyright protection based on concentric rectangles

Abstract

This paper presents an adaptive and robust method for image copyright protection to control ownership and prevent unauthorized usage of image property. The image is transformed into a wavelet domain using a multi-level of lifting wavelet transform; the lowest frequency band is globally divided into several concentric rectangles to withstand cropping. Pixels of a user-selected rectangle are designated for embedding flag bits to protect against rotational attacks. The proposed embedding operation takes into consideration the coefficient of high energy to be identified as potential positions for the embedding process. This procedure reduces the total error presented by the embedding process and protects hidden data against noise and jpeg-compression attacks. A reversible scrambling is applied to a pre-defined region from the watermarked image to prevent unauthorized users from attaining a high quality watermarked image. Experimental results show that the proposed algorithm achieves a range of PSNR (44–50) dB and a normalized correlation range of (1–0.9) for the watermarked image and reconstructed logo. Results also demonstrate the robustness against various attacks, such as rotation, cropping, noise adding, and JPEG-compression.

Keywords

• Watermarking
• Concentric rectangles
• Attacks
• Robustness
• Padding, lifted wavelet transform, potential embedding positions