In this paper we present a combined hashing/watermarking method for image authentication. A robust image hash, invariant to legitimate modifications, but fragile to illegitimate modifications is generated from the local image characteristics. To increase security of the system the watermark is generated using the image hash as a key. Quantized Index Modulation of DCT coefficients is used for wa...

In this paper we propose a wavelet transform based watermarking method. The wavelet coefficients of the watermark are embedded to the most significant coefficients at the low and high frequency bands of the discrete wavelet transform of an image. A multeresolution nature of wavelet transform can be exploit in the process of detection. Experimental results show that the proposed watermarking met...

robust, watermarking, invisible This paper addresses the problem of watermarking a digital image, in order to detect or verify ownership. An invisible and resilient watermark is one that is not ordinarily visible and is robust in the face of common image manipulations such as lossy compression, scaling, cropping, rotation, reflection, and brightness/contrast adjustment. A watermarking scheme is...

in this article, we focus on the complementary role of watermarking with respect to medical information security (integrity, authenticity ...) and management. We review sample cases where watermarking has been deployed. We conclude that watermarking has found a niche role in healthcare systems, as an instrument for protection of medical information, for secure sharing and handling of medical im...

This paper investigates digital data hiding schemes. The concept of information hiding will be explained at first, and its traits, requirements, and applications will be described subsequently. In order to design a digital data hiding system, one should first become familiar with the concepts and criteria of information hiding. Having knowledge about the host signal, which may be audio, image, ...

Watermarking is a technique for labelling digital pictures by hiding secret information in the images. A digital watermark is a kind of marker covertly embedded in a noise tolerant signalsuch as audio or image data. It is typically used to identify ownership of the copyright of such signal. An original image is decomposed into wavelet coefficients. Then, multi-energy watermarking scheme based o...

Digital watermarking technology is a very good method for protecting copyright. In this paper, in terms of requisition of imperceptibility and robustness of watermarking, the coefficient features of Discrete Cosine Transform (DCT) are introduced and a new image watermarking scheme based on Discrete Cosine Transform is proposed. Digital watermark is embedded in original image by subtle perturbat...

By expansion of digital multimedia and networking technology, the problem of ownership protection has become increasingly important. Digital watermarking is an efficient way for copyright protection of digital images. Traditional watermarking techniques degrade the quality of host image by embedding a watermark logo. Facing this problem, a new watermarking approach called zero-watermarking has ...

A good watermarking scheme should be able to perform equally well on all types of images irrespective of image contents because practically watermarking has to be applied to images of all types. In this paper, it is shown that in wavelet based spread spectrum technique, watermarking at level 1 decomposition is better for textured images while watermarking at level 2 decomposition is better for ...

The imaging technology is being enhancing day by day, there are a lot of possibilities of reproduction and manipulation of digital data such as digital image, digital audio and digital video, hence a strong digital copyright mechanism must be produced in place. So the protection of digital data content from unauthorized users and the problem of copyright management plays very vital role. The Di...