A Blind Robust Image Watermarking on Selected DCT Coefficients for Copyright Protection

Abstract

This paper proposes a blind and robust image watermarking technique using Discrete Cosine Transform (DCT) for copyright protection on color images called BRIW-DCT. Each channel of the host image is divided into non-overlapping image blocks with the size of 8×8 pixels. Each image block is transformed into a frequency domain using the DCT transformation. The watermark image is embedded into the host image by modifying the 11th to the 15th DCT coefficient. The experimental result shows that the watermarked image achieved a high PSNR value of 50.4489 dB and a high SSIM value of 0.9991. Furthermore, various attacks are performed on the watermarked image. BRIW-DCT can successfully recover the watermark image from the tampered image, which produces a high NC value of 0.7805 and a low BER value of 0.1126.