• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.6 no.12
• /
• pp.3100-3116
• /
• 2012

Reversible data hiding enables the embedding of messages in a host image without any loss of host content, which is proposed for image authentication that if the watermarked image is deemed authentic, we can revert it to the exact copy of the original image before the embedding occurred. In this paper, we present an improved histogram-based reversible data hiding scheme based on prediction and sorting. A rhombus prediction is employed to explore the prediction for histogram-based embedding. Sorting the prediction has a good influence on increasing the embedding capacity. Characteristics of the pixel difference are used to achieve large hiding capacity while keeping low distortion. The proposed scheme exploits a two-stage embedding strategy to solve the problem about communicating peak points. We also present a histogram shifting technique to prevent overflow and underflow. Performance comparisons with other existing reversible data hiding schemes are provided to demonstrate the superiority of the proposed scheme.

• The KIPS Transactions:PartC
• /
• v.14C no.3 s.113
• /
• pp.221-228
• /
• 2007

For the usage of the different standard technology among DRM vendors, the DRM technologies in today could not guarantee the interoperability between the digital contents and digital devices. While users have been guaranteed the protection of contents, they have to put up with the limitation and inconvenience. The Superdistribution methods that InterTrust has proposed is the content distribution technology which is possible to use the content only by the user authentication with the license regardless of the acquisition of the DRM contents. However, it need a additional license with re-authentication from DRM server when the original contents need to be moved to other devices from the own device. In this paper, to reduce the inconveniences of re-authentication and re-issue procedures of the license and continually to protect the rights of contents on the offline, we propose the DRM system that creates domain between home devices and enable users to freely transfer contents with the domain.

• Journal of the Korea Society of Computer and Information
• /
• v.24 no.12
• /
• pp.59-65
• /
• 2019

Hospital Information System includes a wide range of information in the medical profession, from the overall administrative work of the hospital to the medical work of doctors. In this paper, we proposed a Vision-based Authentication and Registration of Facial Identity in Hospital Information System using OpenCV. By using the proposed security module program a Vision-based Authentication and Registration of Facial Identity, the hospital information system was designed to enhance the security through registration of the face in the hospital personnel and to process the receipt, treatment, and prescription process without any secondary leakage of personal information. The implemented security module program eliminates the need for printing, exposing and recognizing the existing sticker paper tags and wristband type personal information that can be checked by the nurse in the hospital information system. In contrast to the original, the security module program is inputted with ID and password instead to improve privacy and recognition rate.

• Journal of KIISE
• /
• v.42 no.4
• /
• pp.419-426
• /
• 2015

This paper proposes a fingerprint verification system on a fuzzy vault with steganography for a smartphone. While biometric-based authentication can provide strong security, the biometric data must be handled carefully as it cannot be re-enrolled when it is revealed to other people. When the transformed data is used for authentication, the original biometric data can be protected. In this paper, we combine a fingerprint verification system with a fuzzy vault scheme to protect the fingerprint data of a smartphone user. In addition, the transformed data using a fuzzy vault scheme increases the security as it is concealed by the steganography scheme. The result of the experiment using fingerprint databases shows that the proposed scheme provides a high level of convenience and security for authentication of a smartphone having with a fingerprint sensor.

• The KIPS Transactions:PartB
• /
• v.19B no.2
• /
• pp.83-92
• /
• 2012

Multimedia contents can be copied and manipulated without quality degradation. Therefore, they are vulnerable to digital forgery and illegal distribution. In these days, with increasing the importance of multimedia security, various multimedia security techniques are studied. In this paper, we propose a content authentication algorithm based on reversible watermarking which supports JPEG compression commonly used for multimedia contents. After splitting image blocks, a specific authentication code for each block is extracted and embedded into the quantized coefficients on JPEG compression which are preserved against lossy processing. At a decoding process, the watermarked JPEG image is authenticated by extracting the embedded code and restored to have the original image quality. To evaluate the performance of the proposed algorithm, we analyzed image quality and compression ratio on various test images. The average PSNR value and compression ratio of the watermarked JPEG image were 33.13dB and 90.65%, respectively, whose difference with the standard JPEG compression were 2.44dB and 1.63%.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.11
• /
• pp.2874-2892
• /
• 2013

Since security plays an important role in several ZigBee applications, such as Smart Energy and medical sensor applications, ZigBee Specification includes various security mechanisms to protect ZigBee frames and infrastructure. Among them, the Join and Leave operations of ZigBee are investigated in this paper. The current Join-Leave operation is protected by the network key (a kind of group key). We claim it is not adequate to employ the network key for such purpose, and propose a new Join-Leave operation protected by the application link key (a kind of pairwise key), which is based on a more efficient key management scheme than that of ZigBee. Hence, the original Join operation consists of a total of 12 command frames, while the new Join operation consists of only 6 command frames. In particular, the security of the proposed Join-Leave operation is equivalent to or better than that of the original Join-Leave operation. The new Join-Leave operation is extensively analyzed in terms of security and efficiency, and compared with the original Join-Leave operation of ZigBee.

• Journal of KIISE:Information Networking
• /
• v.34 no.3
• /
• pp.168-174
• /
• 2007

In this paper, we propose a reversible watermarking algorithm where an original image can be recovered from the watermarked image. Most watermarking algorithms cause degradation of image quality in original digital contents in the process of embedding watermarks. In the proposed algorithm, the original image can be obtained when the degradation is removed from the watermarked image after extracting watermark information. In the proposed algorithm, we utilize a peak point of image histogram and the location map and modify pixel values slightly to embed data. Because the peak point of image histogram and the location map are employed in this algorithm, there is no need of extra information transmitted to the receiving side. As the locations watermark embedding are identified using the location map, the amount of watermark data can increase through recursive embedding.

• The KIPS Transactions:PartC
• /
• v.14C no.1 s.111
• /
• pp.39-44
• /
• 2007

In this paper, we propose a reversible watermarking method to recover an original image after the watermark has been extracted. Most watermarking algorithms cause degradation of image quality in original digital content in the process of embedding watermark. In the proposed algorithm, the original image can be obtained when the degradation is removed from the watermarked image after extracting watermark information. In the proposed method, we utilize histogram shifting concept and Location Map structure. We could solve the Filp-Flop problem by using Location Map structure and enlarge the information embedding capacity by embedding recursively. Experimental results demonstrate that the embedding information as large as 120k bits can be realized while the invisibility as high as 41dB can be maintained.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.4
• /
• pp.1499-1513
• /
• 2014

This paper proposes a novel blind image watermarking scheme exploiting Block Truncation Coding (BTC). Most of existing BTC-based watermarking or data hiding methods embed information in BTC compressed images by modifying the BTC encoding stage or BTC-compressed data, resulting in watermarked images with bad quality. Other than existing BTC-based watermarking schemes, our scheme does not really perform the BTC compression on images during the embedding process but uses the parity of BTC quantization data to guide the watermark embedding and extraction processes. In our scheme, we use a binary image as the original watermark. During the embedding process, the original cover image is first partitioned into non-overlapping $4{\times}4$ blocks. Then, BTC is performed on each block to obtain its BTC quantized high mean and low mean. According to the parity of high mean and the parity of low mean, two watermark bits are embedded in each block by modifying the pixel values in the block to make sure that the parity of high mean and the parity of low mean in the modified block are equal to the two watermark bits. During the extraction process, BTC is first performed on each block to obtain its high mean and low mean. By checking the parity of high mean and the parity of low mean, we can extract the two watermark bits in each block. The experimental results show that the proposed watermarking method is fragile to most image processing operations and various kinds of attacks while preserving the invisibility very well, thus the proposed scheme can be used for image authentication.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.11
• /
• pp.3576-3583
• /
• 2000

Digital watermarks have recently been proposed for the purposes of copyright ptotechtion and autheutication for multimedia contents. A watermarking technique consists of an algorithm that incorporates a watermarking structure into an image in the spatial or frequency domains. In this paper we proposed a new watermarking method for authentication and integrity of digital images and the proposed algorithm uses the MD5 hash funiction and a symmetric key encryption algorithm. To decide the position of embedding watermark and the bit pasitionin the original image, the secret key is used as an input of the MD5 hash function. The simulation results show that the proposed algorithm has the advantage of difficulty to find positions of inserted watermarks, and keep the similar watermarked image quabty with Wong's method.