HDR Image Watermarking

In this Chapter we survey available solutions for HDR image watermarking. First, we briefly discuss watermarking in general terms, with particular emphasis on its requirements that primarily include security, robustness, imperceptibility, capacity and the availability of the original image during recovery. However, with respect to traditional image watermarking, HDR images possess a unique set of features such as an extended range of luminance values to work with and tone-mapping operators against whom it is essential to be robust. These clearly affect the HDR watermarking algorithms proposed in the literature, which we extensively review next, including a thorough analysis of the reported experimental results. As a working example, we also describe the HDR watermarking system that we recently proposed and that focuses on combining imperceptibility, security and robustness to TM operators at the expense of capacity. We conclude the chapter with a critical analysis of the current state and future directions of the watermarking applications in the HDR domain

A Novel Approch for Digital Image Watermarking Using Cryptography

Medicinal images can be made more secure by using enhanced watermarking technique; it allows us to embed the related information with the image, which provides secrecy, integrity and validation by embedding encrypted digital signature with the image. The diverse characteristics of watermarking algorithms are discussed in this paper. The performance evaluation of embedding the watermark in DWT domains is analyzed taking PSNR and MSE as the evaluation parameters. In this paper, data hiding and cryptographic techniques are combined into one secure simple algorithm. So, the original image is not mandatory at the time of watermark recovery. Because we insert final watermark in DWT domain, so this procedure is robust against many attacks

A robust audio watermarking scheme based on reduced singular value decomposition and distortion removal

This paper presents a blind audio watermarking algorithm based on the reduced singular value decomposition(RSVD). A new observation on one of the resulting unitary matrices is uncovered. The proposed scheme manipulates coefficients based on this observation in order to embed watermark bits. To preserve audio fidelity a threshold- based distortion control technique is applied and this is further supplemented by distortion suppression utilizing psychoacoustic principles. Test results on real music signals show that this watermarking scheme is in the range of imperceptibility for human hearing, is accurate and also robust against MP3 compression at various bit rates as well as other selected attacks. The data payload is comparatively high compared to existing audio watermarking schemes

Digital watermarking : applicability for developing trust in medical imaging workflows state of the art review

Medical images can be intentionally or unintentionally manipulated both within the secure medical system environment and outside, as images are viewed, extracted and transmitted. Many organisations have invested heavily in Picture Archiving and Communication Systems (PACS), which are intended to facilitate data security. However, it is common for images, and records, to be extracted from these for a wide range of accepted practices, such as external second opinion, transmission to another care provider, patient data request, etc. Therefore, confirming trust within medical imaging workflows has become essential. Digital watermarking has been recognised as a promising approach for ensuring the authenticity and integrity of medical images. Authenticity refers to the ability to identify the information origin and prove that the data relates to the right patient. Integrity means the capacity to ensure that the information has not been altered without authorisation. This paper presents a survey of medical images watermarking and offers an evident scene for concerned researchers by analysing the robustness and limitations of various existing approaches. This includes studying the security levels of medical images within PACS system, clarifying the requirements of medical images watermarking and defining the purposes of watermarking approaches when applied to medical images