A novel watermarking scheme based on discrete wavelet transform-singular value decomposition

Due to the rapid advancement in information technology, individuals as well as organizations frequently transfer or share their digital content via cyberspace. The security and integrity of this digital content become a big concern, as any middleman can misuse or temper this content. Digital watermarking is a blessing to protect it from any unwanted tampering. Even though many researchers have implemented various watermarking approaches, but still ownership protection and reliability concerns are not fully mitigated. This paper proposes an improved novel hybrid watermarking scheme by combining discrete wavelet transform (DWT) with singular value decomposition (SVD) to minimize these concerns. At first, the host image is decomposed by multi-level DWT and a two-level SVD is applied to the fourth lower-level coefficient (LL5) of the host image. Then the watermark is inserted into the specified sub-band of the host image. The watermark is extracted in a reverse manner. The hybridization of DWT and SVD ensures that the watermarking technique performs better in terms of visual distortion and robustness. The outcomes of the expeiiment show that our proposed method is more robust, imperceptible, and secure than the existing DWT-SVD based methods, even with a broad watermark scale.