• Title/Summary/Keyword: Adaptive watermark detection algorithm

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Adaptive Watermark Detection Algorithm Using Perceptual Model and Statistical Decision Method Based on Multiwavelet Transform

  • Hwang Eui-Chang;Kim Dong Kyue;Moon Kwang-Seok;Kwon Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.8 no.6
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    • pp.783-789
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    • 2005
  • This paper is proposed a watermarking technique for copyright protection of multimedia contents. We proposed adaptive watermark detection algorithm using stochastic perceptual model and statistical decision method in DMWT(discrete multi wavelet transform) domain. The stochastic perceptual model calculates NVF(noise visibility function) based on statistical characteristic in the DMWT. Watermark detection algorithm used the likelihood ratio depend on Bayes' decision theory by reliable detection measure and Neyman-Pearson criterion. To reduce visual artifact of image, in this paper, adaptively decide the embedding number of watermark based on DMWT, and then the watermark embedding strength differently at edge and texture region and flat region embedded when watermark embedding minimize distortion of image. In experiment results, the proposed statistical decision method based on multiwavelet domain could decide watermark detection.

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An Adaptive Watermark Detection Algorithm for Vector Geographic Data

  • Wang, Yingying;Yang, Chengsong;Ren, Na;Zhu, Changqing;Rui, Ting;Wang, Dong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.1
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    • pp.323-343
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    • 2020
  • With the rapid development of computer and communication techniques, copyright protection of vector geographic data has attracted considerable research attention because of the high cost of such data. A novel adaptive watermark detection algorithm is proposed for vector geographic data that can be used to qualitatively analyze the robustness of watermarks against data addition attacks. First, a watermark was embedded into the vertex coordinates based on coordinate mapping and quantization. Second, the adaptive watermark detection model, which is capable of calculating the detection threshold, false positive error (FPE) and false negative error (FNE), was established, and the characteristics of the adaptive watermark detection algorithm were analyzed. Finally, experiments were conducted on several real-world vector maps to show the usability and robustness of the proposed algorithm.

Adaptive Watermarking Method using Watermark Detection Rate (워터마크 검출율에 기반한 적응적 워터마킹 방법)

  • An, Il-Young
    • The Journal of the Korea institute of electronic communication sciences
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    • v.5 no.5
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    • pp.465-470
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    • 2010
  • This paper proposes an adaptive video watermarking algorithm according to bit detection rate of watermark in MPEG2 system. The watermark strength is adaptively applied as BER(bit error rate) of watermark extracted from decoded frame for motion compensation. Watermark insertion uses a frequency spread spectrum method. A realtime watermark extraction is done directly in the DCT domain during MPEG decoding. The experimental simulations show that PSNR(peak signal to noise ratio) results 31.5dB for a fixed watermark strength and 33.dB for an adaptive watermark strength. Also average BER is 0.126 and less than 0.2 avaliable value.

Robust Blind Image Watermarking Using an Adaptive Trimmed Mean Operator

  • Hyun Lim;Lee, Myung-Eun;Park, Soon-Young;Cho, Wan-Hyun
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.231-234
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    • 2001
  • In this paper, we present a robust watermarking technique based on a DCT-domain watermarking approach and an order statistic(OS) filter. The proposed technique inserts one watermark into each of four coefficients within a 2 ${\times}$ 2 block which is scanned on DCT coefficients in the zig-zag ordering from the medium frequency range. The detection algorithm uses an adaptive trimmed mean operator as a local estimator of the embedded watermark to obtain the desired robustness in the presence of additive Gaussian noise and JPEG compression attacks. The performance is analyzed through statistical analysis and numerical experiments. It is shown that the robustness properties against additive noise and JPEG compression attacks are more enhanced than the previous techniques.

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Wavelet-based Digital watermarking Using Multiple threshold (다중 임계치를 적용한 웨이브릿 기반 디지털 워터마킹 기법)

  • Kim, Jae-Won;Nam, Jae-Yeal
    • The KIPS Transactions:PartB
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    • v.10B no.4
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    • pp.419-428
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    • 2003
  • Recently, digital watermarking has been proposed as a viable solution to the need of copyright protection and authentication of multimedia data. A robust wavelet-based watermark casting scheme and a watermark retrieval technique are suggested in this paper. We present a method which can add the watermark to the significant coefficients in the DWT domain, and does not require the original image in the detection process. In adaptive watermark casting method is developed to select perceptually significant coefficients for each subband using multiple threshold. In the proposed method, an adaptive multiple threshold scheme is used to reflect characteristics of each subband and complexity of image. The watermark is adaptively weighted in different subbands to achieve robustness as well as high perceptual quality. The watermark, Gaussian random sequence is added to the large coefficients but not in the lowest subband in the DWT domain. Experimental results show that the proposed algorithm produced visually very good watermarked image which has good invisibility to human eyes and very robust against various image processing and compression attacks.

Wavelet-Based Digital Watermarking Using Level-Adaptive Thresholding (레벨 적응적 이치화를 이용한 웨이블릿 기반의 디지털 워터마킹)

  • Kim, Jong-Ryul;Mun, Young-Shik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.1
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    • pp.1-10
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    • 2000
  • In this paper, a new digital watermarking algorithm using wavelet transform is proposed. Wavelet transform is widely used for image processing, because of its multiresolution characteristic which conforms to the principles of the human visual system(HVS). It is also very efficient for localizing images in the spatial and frequency domain. Since wavelet coefficients can be characterized by the gaussian distribution, the proposed algorithm uses a gaussian distributed random vector as the watermark in order to achieve invisibility and robustness. After the original image is transformed using DWT(Discrete Wavelet Transform), the coefficients of all subbands including LL subband are utilized to equally embed the watermark to the whole image. To select perceptually significant coefficients for each subband, we use level-adaptive thresholding. The watermark is embedded to the selected coeffocoents, using different scale factors according to the wavelet characteristics. In the process of watermark detection, the similarity between the original watermark and the extracted watermark is calculated by using vector projection method. We analyze the performance of the proposed algorithm, compared with other transform-domain watermarking methods. The experimental results tested on various images show that the proposed watermark is less visible to human eyes and more robust to image compressions, image processings, geometric transformations and various noises, than the existing methods.

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Video Watermarking Using Shot Detection (프레임간 상대적인 차에 의한 셔트 검출 기법을 이용한 비디오 워터마킹)

  • 정인식;권오진
    • Proceedings of the IEEK Conference
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    • 2002.06d
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    • pp.101-104
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    • 2002
  • This paper proposes a unique data embedding algorithm for the video sequence. It describes two processings: shot boundary detection and robust data embedding. First, for the shot boundary detection, instead of using absolute frame differences, block by block based relative frame differences are employed. Frame adaptive thresholding values are also employed for the better detection. Second, for the robust data embedding, we generate message template and then convolve and correlate it with carrier signal. And then we embed data on the time domain video sequence. By using these two methods, watermarks into randomly selected frames of shots. Watermarks are detected well even if several certain shots are damaged because we embed watermark into each shot equally.

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Image Adaptive Block DCT-Based Perceptual Digital Watermarking (영상 특성에 적응적인 블록 DCT 기반 지각적 디지털 워터마킹)

  • 최윤희;최태선
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.41 no.6
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    • pp.221-229
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    • 2004
  • We present new digital watermarking scheme that embeds a watermark according to the characteristics of the image or video. The scheme is compatible with established image compression standard. We define a weighting function using a parent-child structure of the DCT coefficients in a block to embed a maximum watermark. The spatio-frequency localization of the DCT coefficients can be achieved with this structure. In the detection stage, we present an optimum a posteriori threshold with a given false detection error probability based on the statistical analysis. Simulation results show that the proposed algorithm is efficient and robust against various signal processing techniques. Especially, they are robust against widely used coding standards, such as JPEG and MPEG.

The Effect of Mean Brightness and Contrast of Digital Image on Detection of Watermark Noise (워터 마크 잡음 탐지에 미치는 디지털 영상의 밝기와 대비의 효과)

  • Kham Keetaek;Moon Ho-Seok;Yoo Hun-Woo;Chung Chan-Sup
    • Korean Journal of Cognitive Science
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    • v.16 no.4
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    • pp.305-322
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    • 2005
  • Watermarking is a widely employed method tn protecting copyright of a digital image, the owner's unique image is embedded into the original image. Strengthened level of watermark insertion would help enhance its resilience in the process of extraction even from various distortions of transformation on the image size or resolution. However, its level, at the same time, should be moderated enough not to reach human visibility. Finding a balance between these two is crucial in watermarking. For the algorithm for watermarking, the predefined strength of a watermark, computed from the physical difference between the original and embedded images, is applied to all images uniformal. The mean brightness or contrast of the surrounding images, other than the absolute brightness of an object, could affect human sensitivity for object detection. In the present study, we examined whether the detectability for watermark noise might be attired by image statistics: mean brightness and contrast of the image. As the first step to examine their effect, we made rune fundamental images with varied brightness and control of the original image. For each fundamental image, detectability for watermark noise was measured. The results showed that the strength ot watermark node for detection increased as tile brightness and contrast of the fundamental image were increased. We have fitted the data to a regression line which can be used to estimate the strength of watermark of a given image with a certain brightness and contrast. Although we need to take other required factors into consideration in directly applying this formula to actual watermarking algorithm, an adaptive watermarking algorithm could be built on this formula with image statistics, such as brightness and contrast.

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