Tampering with a watermarking-based image authentication scheme

We analyse a recent image authentication scheme designed by Chang et al. [A watermarking-based image ownership and tampering authentication scheme, Pattern Recognition Lett. 27 (5) (2006) 439–446] whose first step is based on a watermarking scheme of Maniccam and Bourbakis [Lossless compression and information hiding in images, Pattern Recognition 37 (3) (2004) 475–486]. We show how the Chang et al. scheme still allows pixels to be tampered, and furthermore discuss why its ownership cannot be uniquely binding. Our results indicate that the scheme does not achieve its designed objectives of tamper detection and image ownership

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

A Feature-Based Fragile Watermarking of Color Image for Secure E-Government Restoration

this research developed a method using fragile watermarking technique for color images to achieve secure e-government tamper detection with recovery capability. Before performing the watermark insertion process, the RGB image is converted first into YCbCr image. The watermark component is selected from the image feature that approximates the original image, in which the chrominance value features as a watermark component. For a better detection process, 3-tuple watermark, check bits, parity bits, and recovery bits are selected. The average block in each 2 x 2 pixels is selected as 8 restoration bits of each component, the embedding process work on the pixels by modifying the pixels value of three Least Significant Bit (LSB) . The secret key for secure tamper detection and recovery, transmitted along with the watermarked image, and the algorithm mixture is used to extract information at the receiving end. The results show remarkably effective to restore tampered image

Fragile Watermarking of Medical Image for Content Authentication and Security

Currently in the health environment, medical images are a very crucial and important part of the medical information because of the large amount of information and their disposal two-dimensional. Medical images are stored, transmitted and recovered on the network. The images users await efficient solutions to preserve the quality and protect the integrity of images exchanged. In this context, watermarking medical image has been widely recognized as an appropriate technique to enhance the security, authenticity and content verification. Watermarking image may bring elements of complementary research methods of classical cryptography. The objective of this paper is to develop a method to authenticate medical images to grayscale, detect falsified on these image zones and retrieve the original image using a blind fragile watermarking technique. We propose a method based on the discrete wavelet transform (DWT) for the application of content authentication. In our algorithm, the watermark is embedded into the sub-bands detail coefficient. The subbands coefficients are marked by adding a watermark of the same size as three sub-bands and a comparison of embedding a watermark at vertical (LH), horizontal (HL) and diagonal (HH) details. We tested the proposed algorithm after applying some standard types of attacks and more interesting. The results have been analyzed in terms of imperceptibility and fragility. Tests were conducted on the medical images to grayscale and color size 512 × 512