Wavelet-based copyright-protection scheme for digital images based on local features

A lossless, robust copyright-protection scheme for digital images based on cryptography and watermarking is proposed. In the proposed wavelet-based scheme, the logo image is not embedded into the protected image. The secret key is generated during the embedding process using local features extracted from the perceptually prominent components of the host image after the digital wavelet transform. Digital signature and time-stamping technologies are then used for further protection. With the secret key, the logo image extraction process can be completed without the host image. Experimental results show that the proposed scheme is effective and robust against common image processing and geometric distortions.