• 한국항행학회논문지
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• 제10권4호
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• pp.406-412
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• 2006

본 논문에서는 워터마크 데이터로써 오디오 신호를 이용한 워터마크 기법과 이미지를 삽입하는 워터마크 기법의 성능을 분석하였다. AWGN 채널 환경에서 OFDM/QPSK 시스템을 이용하여 워터마킹된 영상을 전송하고 워터마크 정보를 추출하였다. 실험결과, 오디오를 이용한 워터마크 삽입 방법이 이미지 기반 방법보다 우수한 바, SNR=3 [dB]까지 오디오 신호가 복원 가능하였다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제7권1호
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• pp.71-76
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• 2007

This paper deals with implementing a steganography based multi-modal biometric system. For this purpose, we construct a multi-biometrics system based on the face and iris recognition. Here, the feature vector of iris pattern is hidden in the face image. The recognition system is designed by the fuzzy-based Linear Discriminant Analysis(LDA), which is an expanded approach of the LDA method combined by the theory of fuzzy sets. Furthermore, we present a watermarking method that can embed iris information into face images. Finally, we show the advantages of the proposed watermarking scheme by computing the ROC curves and make some comparisons recognition rates of watermarked face images with those of original ones. From various experiments, we found that our proposed scheme could be used for establishing efficient and secure multi-modal biometric systems.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2005년도 춘계 학술대회
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• pp.208-214
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• 2005

A number of watermark insertion method is proposed for the protection of audio contents such as MP3 music. In this paper, we propose a VLSI architecture that performs embedding watermark to the audio signal based on the scheme that proposed by XUEYAO LI[1]. This architecture is implemented and simulated in Verilog HDL. This watermark embedding method used a visually recognizable binary image. Despite a unit that determines the watermark embedded intensity is removed to archive low complexity of H/W, our experimental results show that watermarked signal is perceptually transparency and robust to several known attacks.

• International Journal of Contents
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• 제11권3호
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• pp.39-46
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• 2015

When host images are watermarked with CRT (Chinese Remainder Theorem), the watermark images are still robust in spite of the damage of the host images by maintaining the remainders in an unchanged state within some range of the changes that are incurred by the attacks. This advantage can also be attained by "zero-watermarking," which does not change the host images in any way. This paper proposes an improved zero-watermarking scheme for color images on the DCT (Discrete Cosine Transform) domain that is based on the CRT. In the scheme, RGB images are converted into YCbCr images, and one channel is used for the DCT transformation. A key is then computed from the DC and three low-frequency AC values of each DCT block using the CRT. The key finally becomes the watermark key after it is combined four times with a scrambled watermark image. When watermark images are extracted, each bit is determined by majority voting. This scheme shows that watermark images are robust against a number of common attacks such as sharpening, blurring, JPEG lossy compression, and cropping.

• Journal of information and communication convergence engineering
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• 제13권1호
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• pp.62-68
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• 2015

In this paper, we propose a watermarking method for protecting the ownership of three-dimensional (3D) content generated from depth and texture images. After selecting the target areas to preserve the watermark by depth-image-based rendering, the reference viewpoint image is moved right and left in the depth map until the maximum viewpoint change is obtained and the overlapped region is generated for marking space. The region is divided into four subparts and scanned. After applying discrete cosine transform, the watermarks are inserted. To extract the watermark, the viewpoint can be changed by referring to the viewpoint image and the corresponding depth image initially, before returning to the original viewpoint. The watermark embedding and extracting algorithm are based on quantization. The watermarked image is attacked by the methods of JPEG compression, blurring, sharpening, and salt-pepper noise.

• 전기학회논문지
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• 제57권12호
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• pp.2330-2335
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• 2008

In this paper, we proposed a robust watermark scheme for image based on the discrete wavelet transform. In the first, we use the triplet method for embedding and extraction of watermark. Triplet method uses relationship among the discrete wavelet coefficients at the same position in the three detail subband of image. In the second, we use barcode Pattern Image for watermark scheme. By using barcode Pattern Images, a user is able to make many kinds of own watermark. In the third, the proposed method for image watermark provides the invisiblility which the other user can not discriminate watermark from watermarked image. The advantage of the proposed method is visibility when we extracted watermark from the image. The corresponding experimental results show that the proposed method has performance of a robustness from the noise attack.

• 정보처리학회논문지D
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• 제15D권6호
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• pp.857-860
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• 2008

본 논문은 디지털 영상의 저작권을 보호하기 위한 기술로 양자화 영상 워터마킹을 이용한 제거 가능한 로고 기법을 제안한다. 즉, 디지털 영상에 인지 가능한 로고를 삽입하여 저작권을 보호하며, 로고에 의해 제거된 부분의 정보를 워터마킹으로 영상에 삽입하여 정당한 사용 시에는 로고를 제거하고 원영상을 복원할 수 있다. 제안된 방법을 실제 영상에 적용하여 실험해 본 결과, 워터마크가 삽입된 영상이나 로고를 제거하고 복원된 영상 모두 원영상과 차이를 느낄 수 없는 우수한 화질을 보였으며, 저작권 보호 측면에서도 삽입된 로고에 의한 저작권 인지력이 뛰어나 실용적으로 매우 우수한 방법임을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 B
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• pp.606-608
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• 1998

Digital watermarking is the technique which embeds the invisible signal into multimedia data such as audio, video, images, for copyright protection, including owner identification and copy control information. In this paper, a new watermark detection algorithm by local masking cross covariance between watermarked signal and pseudo noise signal is proposed. The proposed algorithm enhances the detection probability for embedding information. Since reducing detection errors for the weak embedding signals, the algorithm improves the image quality and robusts against illegal attack to delete the embedding information and data compression applications such as JPEG and MPEGs.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.857-860
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• 2000

This paper presents a new watermarking method based on wavelet transform. Embedding algorithm call define robust area by varying thresholds and gives a watermark image the priority of significance by analyzing spatial correlation of the watermark image. Detector can adjust thresholds to the distorted watermarked image. Also detector can extract the embedded data without an original image. A new measurement for detecting the correct watermark is suggested. Simulation results show that the embedded watermark is robust against various signal processing and compression attacks.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2002년도 하계학술발표대회 논문집 제21권 1호
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• pp.323-326
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• 2002

In this paper, we propose a watermarking technique that it is possible to winnow illegal contents from scattered contents on the internet. The identification is performed using an embedded unique content ID by the watermarking technique. The proposed watermarking technique accepts A/D-D/A conversion and a lot of lossy compression such as MP3, AAC, WMA and Real Audio. Watermark robustness is enabled using group quantization, selecting watermark inserting point, and error correction code. Test results show that the correct extraction is about $90\%$ and SNR is above $50\~60dB$. The above figures means that the proposed technique is able to extract encoded information at least one more times per audio and that it is very difficult to discriminate between a watermarked audio and a original audio.