• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.656-664
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• 2006

In this paper, we introduce a new LUT based watermarking method for a halftone image. Watermark bits are hidden at pseudo-random locations of halftone image in the proposed method. The pixel values of the halftone image are determined from the LUT entry indexed by both the neighborhood halftone pixels and current grayscale value. The LUT is trained by a set of grayscale images and corresponding halftone images. Advantage of the LUT method is that it can be executed very fast compared with other watermarking methods for a halftone image. Therefore, the algorithm can be embedded in a printer. Experiments for real scanned images showed that the method is a feasible method to hide the large amount of data within a halftone image without noticeable distortion and comparing to the DHED method, is almost same in quality but significantly shorten in processing time.

• International Journal of Computer Science & Network Security
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• v.21 no.9
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• pp.303-316
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• 2021

Digital content protection has recently become an important requirement in biometrics-based authentication systems due to the challenges involved in designing a feasible and effective user authentication method. Biometric approaches are more effective than traditional methods, and simultaneously, they cannot be considered entirely reliable. This study develops a reliable and trustworthy method for verifying that the owner of the biometric traits is the actual user and not an impostor. Watermarking-based approaches are developed using a combination of a color face image of the user and a mobile equipment identifier (MEID). Employing watermark techniques that cannot be easily removed or destroyed, a blind image watermarking scheme based on fast discrete curvelet transform (FDCuT) and discrete cosine transform (DCT) is proposed. FDCuT is applied to the color face image to obtain various frequency coefficients of the image curvelet decomposition, and for high frequency curvelet coefficients DCT is applied to obtain various frequency coefficients. Furthermore, mid-band frequency coefficients are modified using two uncorrelated noise sequences with the MEID watermark bits to obtain a watermarked image. An analysis is carried out to verify the performance of the proposed schema using conventional performance metrics. Compared with an existing approach, the proposed approach is better able to protect multimedia data from unauthorized access and will effectively prevent anyone other than the actual user from using the identity or images.

• ETRI Journal
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• v.29 no.5
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• pp.703-705
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• 2007

An image fidelity assessment using the edge histogram descriptor (EHD) of MPEG-7 is presented. Neither additional data nor fragile watermarking is needed, and there is no need to access the original image as a reference. Only the EHDs of the original image and the received image are required. The peak signal-to-noise ratio (PSNR) obtained by comparing the EHD extracted from the received image and that of the original image is used to assess the noise level of the received image. Experimental results show that the PSNRs calculated from the conventional pixel-to-pixel gray level and from the proposed bin-to-bin EHD maintain a proportional relationship. This implies that the EHD can be used instead of image data for the image fidelity assessments.

• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.422-428
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• 2015

This paper proposes a high performance reversible watermarking (RW) scheme based on a novel compensation strategy. RW embeds data into a host image by modifying its pixel values slightly. It is found that certain modified pixels can be compensated to their original values during the proposed embedding procedure. The compensation effect in the RW scheme can improve the marked image quality significantly. By incorporating the pixel selection method, a higher quality image is obtained, which is verified by extensive experiments.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7C
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• pp.649-653
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• 2009

Although digital image has many advantages including digital image compression and various image processing techniques, the it has the weakness of easy manipulation which led to the development of many digital watermarking techniques. There are various types of digital watermarking algorithms for spatial and spectral domains. This paper presents a watermarking implementation for H.264/AVC codec which is adapted for many multimedia standards.

• Journal of Korea Multimedia Society
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• v.9 no.4
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• pp.505-514
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• 2006

We proposes a multipurpose image watermarking algorithm which embeds visible watermark and invisible watermark into an original image. This is to satisfy the two characteristics of copyright notification of the visible watermark and copyright protection of the invisible watermark. The visible watermark's transparency is highlighted to be easily identified in contrast to the original image and the invisible watermark is embedded in a spatial domain.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.6
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• pp.101-109
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• 2004

This paper proposes an adaptive watermarking algerian technique concerning the visual characteristics of human. To embed watermark to an image, features such as contrast, brightness, and texture are used. The propose method adaptively select blocks and determine the position and intensity of watermark to be applied, concerning the visual characteristics of a human. The experiment involves cropping, image enhancement, low pass filtering, and JPEG compression, which are compared on detectability of watermark against image manipulation and attack

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.3
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• pp.616-621
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• 2005

In this paper. digital watermarking algorithm based on human visual system and transform domain is presented. Firstly, original image is separated into RGB thannels, watermark is embedded into the coefficients of DCT so as to consider a contrast sensitivity and texture degrees. In preprocessing, DCT domain based transform is involved and binary image of visually recognizable patterns is utilized as a watermark. Consequently, experimental results showed that proposed algorithm is robust and imperceptibility such destruction attack as JPEG compression.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.678-683
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• 2009

A lot of researches [1] have been conducted on digital watermark embedding in brightness. A prerequisite for the digital watermark is that the image quality does not change even if the volume of the embedded information increases. Generally, the noise on complex images is perceived than the noise on fiat images. Thus, we present a method for watermarking an image by embedding complex areas by priority. The proposed method has achieved higher image quality of digital watermarking compared to other method that do not take into consideration the complexity of blocks, although the PSNR of the proposed method is lower than for a method not based on block complexity.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.239-242
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• 2002

The rapid expansion of the Internet in the past few years has rapidly increased the availability of digital data such as audio, images and videos to the public. Therefore, The need for copyright protect of digital data are increasing in the internet. In this paper, Color image(RGB model) is transformed into LUV model, it includes the characteristics of, human vision and then the U or V component is transformed into 3-level wavelet transform. we can insert watermark to several objects of an image separately The experimental results showed that the proposed watermarking algorithm was better than to other RGB watermarking algorithm.