A Digital Watermarking Scheme Using Hologram Quantization

In this paper, we propose a digital watermarking scheme that uses hologram quantization to spread the watermark information and analyze the cover image detail. The watermark is a hologram generated using a QR code and quantization based on the cover image. This hologram is transformed by a discrete fractional random transform with a random seed β to make the watermark. The generated watermark can then be embedded into the subband of the discrete wavelet transform (DWT). The proposed scheme includes encryption techniques for security, and is robust because the watermark is inserted in the DWT. When conventional methods are used to watermark an image, the invisibility is poor in the boundary region, but using the proposed method reduces the bit error rate to just 0–0.45%.