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This paper proposes a blind multi-watermarking scheme based on designing two back-to-back encoders. The first encoder is implemented to embed a robust watermark into remote sensing imagery by applying a Discrete Cosine Transform (DCT) approach. Such watermark is used in many applications to protect the copyright of the image. However, the second encoder embeds a fragile watermark using 'SHA-1' hash function. The purpose behind embedding a fragile watermark is to prove the authenticity of the image (i.e. tamper-proof). Thus, the proposed technique was developed as a result of new challenges with piracy of remote sensing imagery ownership. This led researchers to look for different means to secure the ownership of satellite imagery and prevent the illegal use of these resources. Therefore, Emirates Institution for Advanced Science and Technology (EIAST) proposed utilizing existing data security concept by embedding a digital signature, "watermark", into DubaiSat-1 satellite imagery. In this study, DubaiSat-1 images with 2.5 meter resolution are used as a cover and a colored EIAST logo is used as a watermark. In order to evaluate the robustness of the proposed technique, a couple of attacks are applied such as JPEG compression, rotation and synchronization attacks. Furthermore, tampering attacks are applied to prove image authenticity. Downloaded From: http://proceedings.spiedigitallibrary.org/ on 08/25/2015 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx Proc. of SPIE Vol. 8895 889504-4 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 08/25/2015 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

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This paper deals with a blind hybrid digital watermarking algorithm for the copyright protection and authentication of magnetic resonance tomography images. Medical image watermarking requires extreme care when embedding watermark information in the medical images, to protect the image quality from being violated and to avoid the wrong diagnosis that might occur. The proposed algorithm contains robust watermark for the ownership protection and fragile watermarks for checking the authenticity. In the proposed algorithm, the medical image is divided into two regions, called the Region of Interest and Region of Non-Interest using histogram technique and the watermarks are embedded in both wavelet domain and spatial domain in the Region of Non-Interest Area. The proposed hybrid watermarking technique was successfully tested on a variety of MRI medical images and offerd high peak signal to noise ratio and similarity structure index measure values.