Exploiting Digital Watermarking to Preserve Integrity of the Digital Holy Quran Images

The Holy Quran is very important to the Muslims with respect to its authenticity. This paper studies and exploits the fragile watermarking method that works on block-wise in the wavelet domain and pixel-wise in the spatial domain. The input image is transformed into wavelet domain using discrete wavelet transform. Then, using block-wise based approach the coefficients matrix of wavelet-transformed image is divided into several blocks for further watermark the authentication bits. The authentication bits are embedded into a block with 2n elements by modifying only one original element with ±1. Afterward, the modified coefficients matrix is inverted back to the spatial domain. The difference of coefficients matrix of the modified and the inverse is embedded on the pixel by changing one insignificant bit. Obviously, it ensures imperceptible watermark on the host image. Public-key cryptography is utilized to encrypt the authentication bits. The authentication bits are derived from input image using well-known hash function. The experimental result shows proposed method is able to detect any manipulation on the content of digital Holy Quran and thus preserves its content´s integrity.