• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2002년도 ITC-CSCC -1
• /
• pp.454-457
• /
• 2002

In this paper, we proposed digital audio watermarking algorithm for high quality audio. Nowadays, digital watermark used to confirm to digital copyright protection, not only digital image but also digital audio is active in the digital watermarking study. In this paper, we proposed digital audio watermarking algorithm using psychoacoustics model and MDCT/IMDCT (Modified Discrete Cosine Transform/Inverse Modified Discrete Cosine Transform) for the high quality audio watermark. In the proposed scheme, we used to 441KHz, 128kbps and stereo audio data for audio watermarking algorithm. Audio data is passed by MDCT; watermark can be inserted into the frequency domain with 256,1024 and 2048 interval.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2002년도 ITC-CSCC -1
• /
• pp.466-469
• /
• 2002

Using intelligent information contained within the speech to identify the specific hidden data in the watermarked multimedia data is considered to be an efficient method to achieve the speech digital watermarking. This paper presents the performance comparison between various types of speech codec in order to determine an appropriate one to be used in digital watermarking applications. In the experiments, the speech signal encoded by four different types of speech codec, namely CELP, GSM, SBC and G.723.1codecs is embedded into a grayscale image, and theirs performance in term of speech recognition are compared. The method for embedding the speech signal into the host data is borrowed from a watermarking method based on the zerotrees of wavelet packet coefficients. To evaluate efficiency of the speech codec used in watermarking applications, the speech signal after being extracted from the attacked watermarked image will be played back to the listeners, and then be justified whether its content is intelligible or not.

• 한국멀티미디어학회논문지
• /
• 제10권12호
• /
• pp.1601-1611
• /
• 2007

In this paper, we presented geometric CAD watermarking scheme for Architectural design drawings using line, arc, and circle components to prevent infringement of copyright from unlawfulness reproductions and distribution. The conventional CAD watermarking scheme can be applied to both line and arc components. But the proposed scheme consists of line, arc and circle watermarking schemes for three basic components of CAD design. After extracting line, arc and circle components from designed drawing, the watermark is embedded into the length of Line component, the angle of arc component, and the radius of circle component considering the robustness against various geometric transformations. The embedding strengths in each component are determined to be preserving the transparency of the watermark. By experimental result, we confirmed the robustness and the invisibility of embedded watermarks in several conversions of architectural design drawing.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• 제1권1호
• /
• pp.24-28
• /
• 2001

Wavelet transforms are used for implementing digital watermarking methods in the frequency domain. In this paper, we construct the digital watermarking using various wavelet transforms such as the Daubechies transform, Coiflets transform, Symlets transform and the biorthogonal transform, and we compare each digital watermarking method with the others. We investigate the preservation of the watermark after the data compression attack based on the discrete on the discrete cosine transform. We show that the biorthogonal wavelet, denoted by bior3.5, has the best performance among the wavelet types we selected in an experiment.

• Journal of information and communication convergence engineering
• /
• 제16권3호
• /
• pp.179-188
• /
• 2018

This paper proposes a quick response (QR) barcode watermarking algorithm in order to improve readability of the QR barcode in a JPEG image. The proposed algorithm embeds a watermark in a wavelet based-low frequency band for watermark robustness, and visually extracts a QR barcode after embedding the QR barcode image with confidential information into the original image via imperceptible watermarking technology. The visually extracted QR barcode watermark uses an approach to authenticate the ownership more easily through a common hardware and software-based mobile barcode reader app. Therefore, the QR barcode watermark may improve the ability to easily detect watermarks efficiently as well as imperceptibility and robustness, which is the main watermark requirement by embedding the QR barcode with watermark text information in a digital image and when compare to conventional watermarks.

• 한국통신학회논문지
• /
• 제28권9C호
• /
• pp.898-907
• /
• 2003

대부분의 영상 워터마킹 기법은 공격에 대한 강인성과 비가시성을 동시에 만족시키기 위하여 중간 주파수 영역에 워터마크를 삽입하는데 반해, 본 논문에서는 웨이브렛 분해된 입력 영상에서 가장 낮은 주파수 성분들을 갖는 부대역의 계수들에 워터마크 정보를 삽입하는 새로운 워터마킹 방법을 제안한다. 제안한 새로운 워터마크 삽입 알고리즘은 삽입된 워터마크 비트의 강인성을 보다 높이도록 하기 위해 웨이브렛 최저주파수 대역에서 랜덤하게 선택된 계수들에 대해 양자화 방식을 이용하여 삽입이 이루러진다. 실험 결과에서 나타난 것처럼 제안한 새로운 삽입 방식이 비가시성과 강인성 측면에서 우수한 특성을 보이는 것을 확인하였다.

• 한국멀티미디어학회:학술대회논문집
• /
• 한국멀티미디어학회 2000년도 추계학술발표논문집
• /
• pp.493-497
• /
• 2000

Fragile watermarking is a technique far autoentication/integrity of digital data. Unlike robust watermarking, il has to design to be vulnerable against some slight processing to verify the modification of digital data. Feature of fragile watermarking is to identify the modifications of data and to locate some places modification occurred at the same time, so it has to identify slight changes of small range if possible. In this paper, fragile watermarking is proposed that the changes of small range on image can be identified using the watermark sequence with period and the values of low bit planes in an image.

• 한국멀티미디어학회논문지
• /
• 제9권6호
• /
• pp.709-719
• /
• 2006

To protect against unlawful reproductions and distribution, the current paper proposes a digital watermarking technique for architectural drawings produced using a CAD system. First, the POLYLINEs are extracted from the drawing; then, an adaptive algorithm is used to embed a watermark in the characteristics of each POLYLINE. Next, the CIRCLEs are embedded using an adaptive watermarking algorithm related to the radius of circle from drawing. The proposed watermarking scheme is robust to various attacks, such as the geometrical transformation. Additionally, the proposed method satisfies the requirement of transparency for CAD program. It used AutoCAD 2002, which is commonly used as a CAD program for experiments. Experimental results confirmed the robustness and invisibility of the embedded watermarks in several conversions of an architectural drawing.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
• /
• pp.18-21
• /
• 2007

Digital image watermarking is a technology used in copyrighting of digital images by embedding unremovable informations. In this paper, a pixel-domain look-up-table-based watermarking algorithm is presented. With this methodology, the watermark was embedded in the host image, but we did not observe any distortion at certain specific region of interest. This means the proposed method is preferred in case of satellite images. Then, the image manipulation tool which is called 'StirMark' will be used to perform many kinds of attacks such as rotation, scaling, filtering and compression on the watermarked image. Finally, the effectiveness of a watermarking technique in terms of 'robustness' and 'data integrity' criteria will be measured by calculating PSNR of watermark and watermarked image.

• 디지털콘텐츠학회 논문지
• /
• 제6권2호
• /
• pp.95-99
• /
• 2005

최근 멀티미디어 산업의 팽창과 네트워크 기술의 발전으로 문서, 음성, 사진 및 동영상 데이터 둥의 다양한 컨텐츠들에 대한 저작권 보호의 필요성이 절실히 요구되게 되었다. 현재 사용되는 암호화 기법의 컨텐츠 보호는 디지털 컨텐츠에 대하여 접근이 극히 제한된다는 단점과 한번 암호가 풀린 컨텐츠는 더 이상 보호 할 수 없다는 한계를 가지고 있다. 이러한 문제점을 해결하기 위한 하나의 수단으로 디지털 워터마킹(Digital Watermark) 기법이 제안 되었다. 본 연구에서는 디지털 워터마크 기술에 대한 표준화, 기술 동향 향후 발전방향등에 대한 국내외 연구 내용을 조사하고 향후 기술적인 동향을 알아본다.