Abstract—Image watermarking is of interesting in the multimedia and information security research fields. This paper presents an improved discrete cosine transform (DCT)-based image watermarking scheme using the fast Walsh Hadamard transform (FWHT) for image authentication. As a fast transformation with good energy compaction, this transform is frequently applied in image processing operations, such as image data compression and filtering. In the proposed scheme, the fast Walsh Hadamard transform is applied to the watermark signal before it is embedded into the DCT coefficients. The low signal coefficients are expected to produce a high visual quality of the watermarked image. The performance of the proposed scheme is then compared with the DCT-based image watermarking scheme performance itself. This experiment is simulated by several attacks to test the robustness of the watermark, such as noise insertion, JPEG compression, cropping, rotation, and scaling. Experimental results show that the imperceptibility of the watermarked image could be improved. The robustness of the watermark is also improved depend on the level distortion.

Index Terms—Image watermarking, discrete cosine transform, fast Walsh Hadamard transform, imperceptibility, robustness, watermarked image.

Aris Marjuni and Mohammad Fasizal Ahmad Fauzi are with the Faculty of Engineering, Multimedia University, Cyberjaya 63100, Selangor, Malaysia (e-mail: arism240669@gmail.com , faizal1.mmu@mmu.edu.my).
Rajasvaran Logeswaran is with the School of Engineering, Science and Technology, Nilai University College 71800 Nilai, Negeri Sembilan , Malaysia (e-mail: logeswaran@gmail.com).
Swee-Huay Heng is with the Faculty of Information Science & Technology, Multimedia University, Bukit Beruang 75450, Melaka, Malaysia (e-mail: shheng@mmu.edu.my)