• Title/Summary/Keyword: watermark

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Reversible Watermarking based on Predicted Error Histogram for Medical Imagery (의료 영상을 위한 추정오차 히스토그램 기반 가역 워터마킹 알고리즘)

  • Oh, Gi-Tae;Jang, Han-Byul;Do, Um-Ji;Lee, Hae-Yeoun
    • KIPS Transactions on Software and Data Engineering
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    • v.4 no.5
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    • pp.231-240
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    • 2015
  • Medical imagery require to protect the privacy with preserving the quality of the original contents. Therefore, reversible watermarking is a solution for this purpose. Previous researches have focused on general imagery and achieved high capacity and high quality. However, they raise a distortion over entire image and hence are not applicable to medical imagery which require to preserve the quality of the objects. In this paper, we propose a novel reversible watermarking for medical imagery, which preserve the quality of the objects and achieves high capacity. First, object and background region is segmented and then predicted error histogram-based reversible watermarking is applied for each region. For the efficient watermark embedding with small distortion in the object region, the embedding level at object region is set as low while the embedding level at background region is set as high. In experiments, the proposed algorithm is compared with the previous predicted error histogram-based algorithm in aspects of embedding capacity and perceptual quality. Results support that the proposed algorithm performs well over the previous algorithm.

UCI Embedder: A Real-time Broadcast-Content-Identifier Watermarking System for Broadcast Content Distribution Services (방송콘텐츠 유통서비스를 위한 실시간 콘텐츠식별자 은닉삽입 시스템)

  • Kim, Youn-Hee;Kim, Hyun-Tae;Lee, Joo-Young;Nam, Je-Ho
    • Journal of Broadcast Engineering
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    • v.16 no.3
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    • pp.394-402
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    • 2011
  • We introduce the standard content identifier Universal Content Identifier (UCI) and a watermarking system that embeds UCI for the broadcast content distribution services. Our proposed UCI embedder is designed in consideration of integrating with the previously established broadcast system and protecting the illegal distribution of broadcast contents. Our goal is that when broadcast content is transmitted, 28 byte UCI is embedded imperceptibly in the content itself in real-time and the embedded UCI is successfully extracted not only in the typical format used in the broadcast content distribution service but also in the illegally distributed broadcast contents. Usually the illegally distributed contents are modified from the original by changing resolutions, frame rates, or adjusting colors. In this paper, we present a watermarking scheme that embeds 28 byte UCI in broadcast content in real-time while keeping the visual quality high and the embedded watermark robust enough to survive through the various modification. The experimental results show that the embedded UCI remains in the various modified versions of content and that the visual degradation by embedding is not noticeable.

Security Analysis and Improvement of an Anonymous Asymmetric Fingerprinting Scheme with Trusted Third Party (익명적 비대칭 핑거프린팅 기법의 보안 취약성 분석 및 개선 방안)

  • Kwon, Sae-Ran
    • Journal of KIISE:Computer Systems and Theory
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    • v.36 no.5
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    • pp.396-403
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    • 2009
  • An anonymous asymmetric fingerprinting protocol combined with watermarking techniques, is one of the copyright protection technologies keeping both right of a seller and that of a buyer, where a seller and an anonymous buyer perform such a protocol that employs various cryptographic tools in order that the seller does not know the exact watermarked copy that the buyer receives, while inserting an invisible non-removable fingerprint i.e., each different unique watermark, into each copy of the digital content to be sold. In such a protocol innocent buyers are kept anonymous during transactions, however, the unlawful reseller is unambiguously identified with a real identity as a copyright violator. In 2007, Yong and Lee proposed an anonymous asymmetric fingerprinting scheme with trusted third party. In this paper we point out the weakness of their scheme such as: the buyer with intention can remove the fingerprint in the watermarked content, because he/she can decrypt the encrypted fingerprint with a symmetric key using man-in-the-middle-attack; a real identity of a buyer can be revealed to the seller through the identification process even though he/she is honest. Furthermore, we propose an improved secure and efficient anonymous asymmetric fingerprinting scheme which enables to reduce the number of communication between the participants.

An Illegally-copied App Detecting Method by Using Odex File in Android Platform (안드로이드 플랫폼에서 odex 파일을 이용한 불법 복제 앱 탐지 방법)

  • Cho, Dueckyoun;Choi, Jaeyoung;Kim, Eunhoe;Gang, Gi-Du
    • Journal of Internet Computing and Services
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    • v.16 no.2
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    • pp.67-75
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    • 2015
  • According to the changes of the mobile environments, the usage and interest of the Android apps have been increased. But the usage of illegally-copied apps has been also increased. And the transparency and dependability of the app markets has been decreased. Therefore there are many cases for the copyright infringement of app developers. Although several methods for preventing illegally-copied apps have been studied, there may exist possible ways to bypass the methods. Since it is difficult to find out the first distributors of the illegally-copied apps, it is not easy to punish them legally. This paper proposes the method of detecting illegally-copied apps. The proposed detector can detect the illegally-copied apps using odex file, which is created when the app is installed. The detector can also find out the information of the first distributors based on forensic watermark technique. Since the illegally-copied app detector is running as a service on the system server, it is granted that the detector hides from the users. As an experiment result, the illegally-copied app detector takes on average within 0.2 seconds to detect and delete an illegally-copied app.

Study on SCS CN Estimation and Flood Flow Characteristics According to the Classification Criteria of Hydrologic Soil Groups (수문학적 토양군의 분류기준에 따른 SCS CN 및 유출변화특성에 관한 연구)

  • Ahn, Seung-Seop;Park, Ro-Sam;Ko, Soo-Hyun;Song, In-Ryeol
    • Journal of Environmental Science International
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    • v.15 no.8
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    • pp.775-784
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    • 2006
  • In this study, CN value was estimated by using detailed soil map and land cover characteristic against upper basin of Kumho watermark located on the upper basin of Kumho river and the hydrologic morphological characteristic factors were extracted from the basin by using the DEM document. Also the runoff analysis was conducted by the WMS model in order to study how the assumed CN value affects the runoff characteristic. First of all, as a result of studying the soil type in this study area, mostly D type soil was Identified by the application of the 1987 classification criteria. However, by that in 1995, B type soil and C type soil were distributed more widely in that area. When CN value was classified by the 1995 classification criteria, it was estimated lower than in 1987, as a result of comparing the estimated CNs by those standars. Also it was assumed that CN value was underestimated when the plan for Geum-ho river maintenance was drawn up. As a result of the analysis of runoff characteristic, the pattern of generation of the classification criteria of soil groups appeared to be similar, but in the case of the application of the classification criteria in 1995, the peak rate of runoff was found to be smaller on the whole than in the case of the application of the classification criteria in 1987. Also when the statistical data such as the prediction errors, the mean squared errors, the coefficient of determination and other data emerging from the analysis, was looked over in total, it seemed appropriate to apply the 1995 classification criteria when hydrological soil classification group was applied. As the result of this study, however, the difference of the result of the statistical dat was somewhat small. In future study, it is necessary to follow up evidence about soil application On many more watersheds and in heavy rain.

Feasibility of the Lapse Rate Prediction at an Hourly Time Interval (기온감률의 일중 경시변화 예측 가능성)

  • Kim, Soo-ock;Yun, Jin I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.18 no.1
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    • pp.55-63
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    • 2016
  • Temperature lapse rate within the planetary boundary layer shows a diurnal cycle with a substantial variation. The widely-used lapse rate value for the standard atmosphere may result in unaffordable errors if used in interpolating hourly temperature in complex terrain. We propose a simple method for estimating hourly lapse rate and evaluate whether this scheme is better than the conventional method using the standard lapse rate. A standard curve for lapse rate based on the diurnal course of temperature was drawn using upper air temperature for 1000hPa and 925hPa standard pressure levels. It was modulated by the hourly sky condition (amount of clouds). In order to test the reliability of this method, hourly lapse rates for the 500-600m layer over Daegwallyeong site were estimated by this method and compared with the measured values by an ultrasonic temperature profiler. Results showed the mean error $-0.0001^{\circ}C/m$ and the root mean square error $0.0024^{\circ}C/m$ for this vertical profile experiment. An additional experiment was carried out to test if this method is applicable for the mountain slope lapse rate. Hourly lapse rates for the 313-401m slope range in a complex watershed ('Hadong Watermark 2') were estimated by this method and compared with the observations. We found this method useful in describing diurnal cycle and variation of the mountain slope lapse rate over a complex terrain despite larger error compared with the vertical profile experiment.

Copyright Protection for Fire Video Images using an Effective Watermarking Method (효과적인 워터마킹 기법을 사용한 화재 비디오 영상의 저작권 보호)

  • Nguyen, Truc;Kim, Jong-Myon
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.8
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    • pp.579-588
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    • 2013
  • This paper proposes an effective watermarking approach for copyright protection of fire video images. The proposed watermarking approach efficiently utilizes the inherent characteristics of fire data with respect to color and texture by using a gray level co-occurrence matrix (GLCM) and fuzzy c-means (FCM) clustering. GLCM is used to generate a texture feature dataset by computing energy and homogeneity properties for each candidate fire image block. FCM is used to segment color of the fire image and to select fire texture blocks for embedding watermarks. Each selected block is then decomposed into a one-level wavelet structure with four subbands [LL, LH, HL, HH] using a discrete wavelet transform (DWT), and LH subband coefficients with a gain factor are selected for embedding watermark, where the visibility of the image does not affect. Experimental results show that the proposed watermarking approach achieves about 48 dB of high peak-signal-to-noise ratio (PSNR) and 1.6 to 2.0 of low M-singular value decomposition (M-SVD) values. In addition, the proposed approach outperforms conventional image watermarking approach in terms of normalized correlation (NC) values against several image processing attacks including noise addition, filtering, cropping, and JPEG compression.

A Watermarking Scheme Based on k-means++ for Design Drawings (k-means++ 기반의 설계도면 워터마킹 기법)

  • Lee, Suk-Hwan;Kwon, Ki-Ryong
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.46 no.5
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    • pp.57-70
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    • 2009
  • A CAD design drawing based on vector data that is very important art work in industrial fields has been considered to content that the copyright protection is urgently needed. This paper presents a watermarking scheme based on k-means++ for CAD design drawing. One CAD design drawing consists of several layers and each layer consists of various geometric objects such as LINE, POLYLINE, CIRCLE, ARC, 3DFACE and POLYGON. POLYLINE with LINE, 3DFACE and ARC that are fundamental objects make up the majority in CAD design drawing. Therefore, the proposed scheme selects the target object with high distribution among POLYLINE, 3DFACE and ARC objects in CAD design drawing and then selects layers that include the most target object. Then we cluster the target objects in the selected layers by using k-means++ and embed the watermark into the geometric distribution of each group. The geometric distribution is the normalized length distribution in POLYLINE object, the normalized area distribution in 3DFACE object and the angle distribution in ARC object. Experimental results verified that the proposed scheme has the robustness against file format converting, layer attack as well as various geometric editing provided in CAD editing tools.

Metadata production system based on MPEG-21 IPMP for protection and management of The Digital contents (디지털 콘텐츠 보호 관리를 위한 MPEG-21 IPMP 기반의 메타데이터 저작 시스템)

  • Ryu Kwang-Hee;Hong Hyen-Woo;Kim Kwang-Yong;Kim Jae-Gon;Jung Hoe-Kyung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.577-580
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    • 2006
  • The rapidly growth of Internet is main factor that activates the Digital Contents market. However imprudent Digital Contents market could be shrunk by imprudent illegal copy and delivery. MPEG(Moving Picture Experts Group) proposed MPEG-21 Multimedia frameworks in order to solve these problem. IPMP is parts of MPEG-21 Multimedia Frameworks, when Digital Contents goes through production delivery consumption, which defines standard to keep the Digital Contents in safety. Currently IPMP defined by FCD(Final Committee Draft) level. Therefore development of system which applied to latest standard to protect and manage the Digital Contents is required. and the system consists of fourth organizations which means Metadata Production server, Tool server, License server, Consumption server. In this Paper, we made production server to parse REL(Rights Expression Language) document that has right information for content from license server, and create metadata based on MPEG-21 IPMP about the content that applied to watermark. then, after it do remuxing, transmit the protected data to consumption server.

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Numerical Analysis of Riverbed Changes at the Downstream of the Ji-Cheon (수치모형을 이용한 지천하류부의 하상변동 분석)

  • Choi, Ho;Rim, Chang-Soo;Jung, Jae-Wook
    • Journal of the Korean Society of Hazard Mitigation
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    • v.11 no.3
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    • pp.117-125
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    • 2011
  • River bed variation drops storage capacity of dams and reservoirs, and furthermore deteriorates safety of banks and peers. Therefore, understanding of bed variation is important to use and manage river water. Study section is downstream part of Ji- Cheon nearby Ji-Cheon Bridge which is located in Gum river basin. The river surveying at fourteen places with the length of 1,320m were undertaken on November 7, 2003 and September 24, 2004, and the results of river surveying were analyzed for the study. Real bed variation was compared with the simulation results of HEC-6 and GSTARS 3.0. Cross section data for the simulation of HEC-6 and GSTARS3.0 were composed of the basis of river surveying data on November 7, 2003. Hydrological data were acquired from Gu-Ryong watermark located at Ji-Chun Bridge. The research results revealed that when using Toffaleti equation, simulation results of two models were similar to the real bed variation. The bed variation simulated by using GSRARS 3.0 with only one stream tube was similar to the real bed variation. The bed variation simulated by using two models(HEC-6 and GSTRARS 3.0) with Toffaleti equation was also similar to the real bed variation. Therefore, it is expected that HEC-6 and GSTARS 3.0 models have applicability to predict the bed variation at the downstream of Ji-Cheon.