A Hybrid Approach for Image Security by Combining Watermarking with Encryption

Abstract

In todays networked world, security of digital data is of uttermost importance. Digital data are extensively used throughout the world in almost every field. Banking, social media, hospitals, hotels, theaters are some of the areas where security of digital data is very important. The need for securing the data increases, as they need to travel over the network vulnerable. Thus, before sending digital data over the insecure network, The sender must take some measures to ensure protection of the sensitive data. For this, the sender may choose various techniques such as watermarking, cryptography or steganography. These techniques ensure different aspects of security. Watermarking ensures data authentication and copyright protection, whereas cryptography and steganography both ensures confidentiality and integrity. For very sensitive data any one of these techniques is not sufficient, thus a hybrid approach is recommended to ensure multi-dimensional security. In this thesis, a hybrid approach for securing images using watermarking and encryption is presented to improve the overall security of images. This approach ensures the integrity, authenticity, copyright protection, confidentiality of images. Here security of digital data is ensured twice. First using encryption, it is encrypted and then it is hide in cover image using watermarking. Watermarking is also applied in edges of cover image, due to which visual quality of the image is maintained. Using this approach overall security of the image is improved. Experimental results show that quality of image after watermarking is improved. Results were compared on PSNR and MSE metrics.