• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2009.01a
• /
• pp.508-511
• /
• 2009

The infringement of the copyright is a problem by the distribution of digital contents copied illegally. The digital watermark is expected as a thing preventing unjust copying by burying information in digital data such as image, animation, the sound, TV, radio and movies. [1] [2]But a noise is included in a digital watermark reproduction image. So there is the case that the certification of the reproduction image has difficulty with. If a computer cannot recognize the information reproduced from digital watermarking, the information does not have a meaning. This paper aimed at improvement of the proof of a digital-watermarking reproduction image. And it is verified whether the difference of the form of a character affects the degree of correlation.

• Journal of Broadcast Engineering
• /
• v.14 no.4
• /
• pp.428-437
• /
• 2009

A high dynamic range (HDR) image can represent real world scenes that have a wide range of luminance intensity. However, compared with the range of real world luminance, conventional display devices have a low dynamic range (LDR). To display HDR images onto conventional displayable devices such as monitors and printers, we propose the logarithmic based global reproduction algorithm that considers the features of the image using reproduction parameters. Based on the characteristics of the image, we first modify the input luminance values for reproducing perceptually tuned images and then obtain the displayable output values directly. The experimental results show that the proposed algorithm achieves good subjective results while preserving details of the image; furthermore, the proposed algorithm has a fast, simple and practical structure for implementation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.5 no.11
• /
• pp.2160-2174
• /
• 2011

In this paper, a new technique for color reproduction based on color variation characteristics of digital camera under a dim light condition is proposed. Generally, photographers should adjust a camera exposure properly for obtaining an image with real color tone of subjects. Thus, in case of taking a picture under a dim light condition, the exposure time of a camera has to be relatively longer than the one under a bright light condition. Although images with real color tone of the subject are obtained, the images may get blurred due to the shaky hands of photographer holding the camera. In order to avoid the blur effect, an input image is captured from a camera set as a short exposure time under a dim light condition. Then we propose a method to reproduce color tone of the dim input image. To this end, color variation characteristics which represent color variations of a digital camera are first extracted by analyzing the Macbeth color checker images taken under various exposure values. Then, a color reproduction is performed by an estimation based on the color variation characteristics. Experimental results have shown that the proposed method has achieved better performance of color reproduction, compared with existing methods.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.23 no.1
• /
• pp.1-11
• /
• 2005

The propose of this study investigated the reproduction of color image on a CRT monitor, for a range of different values of monitor gamma. We have used the GOG(gain-offset-gamma) model of the behavior of CRT. Color difference have been computed in a color space, based on the CIELAB color appearance model. The 133 patch defined linearly color sample and 24 patch defined printing color target were used, and were subjected to the influence of nine different gamma value. The result shows that netural color is increasing the decrease range of luminance black color than white color. These results concern correct in the context display of color reproduction.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2004.08a
• /
• pp.432-435
• /
• 2004

The skin color of a human being is the important memory color influencing image quality for color display. Therefore, in this paper, the preferred skin color axis is defined on HSV color space by analyzing some previous research, and the preferred skin color reproduction algorithm is performed by rotating the center axis of skin distribution of an input image to the preferred skin color axis.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.45 no.1
• /
• pp.29-37
• /
• 2008

With the rapid development of display technology as well as the diversity of display, image quality assessment plays an important role in display color reproduction. The image quality has described by objective evaluation based on the physical measured data, such as contrast ratio, color reproduction range, color temperature, and gamma characteristics, etc., however, the final judgement is achieved by perceptual quality assessment of observers. Therefore, it is necessary to investigate the relationship between physical performance of display and perceptual image quality. Thus, in order to evaluate objectively the color reproduction characteristics of two mobile displays, TFT-LCD and AMOLED, we measured the darkroom contrast ratio of full screen, luminance and color temperature of full-screen white, full-screen gray and color linearity, tone reproduction of color scales for each RGB primary, and color reproduction range. Then the pair-wise comparison is implemented for image experts and naive observers not only to judge their preference on principal evaluation attributes but also to subjectively describe perceived image quality. Through two evaluation processes, we derived the objective bases that can prove the results of subjective image quality assessment by interconnecting physical factors that have influence on observers' preference judgements. Finally, this paper provided important information for improving the image quality and increasing preference from an observer's point of view.

• The Journal of the Korea Contents Association
• /
• v.12 no.8
• /
• pp.87-95
• /
• 2012

We propose that a subjective image quality assessment based on objective image quality factors in order to evaluate objectively preference of consumers. In other words, we define objective image quality factors which are easy to accept by manufacturers and they are composed of subjective image quality assessment questionnaires. Also, portrait image is selected by stimulus in order to persue easiness of evaluation for the general subjects. Throughout a subjective image quality assessment model, we evaluate recognition of image quality by consumers and analyze the effectiveness of correlation in terms of the final image quality preference. Analyzing the relationship between image quality factors, we can figure out the preferable image quality and confirm the positive effects on consumers' recognition of image quality. In the results, there are strong relationship between preference and color reproduction, dynamic range, noise, and resolution respectively. especially, the characteristic of portrait, there is high correlation between color reproduction and preference.

• The Journal of the Korea Contents Association
• /
• v.10 no.8
• /
• pp.186-197
• /
• 2010

Recent changes show that the goals of reproduction devices have changed from accurately reproducing scenes to improving user preference. It implies that the directions in developing cameras, the most common reproduction devices, are moving from performance-centered to quality-centered, from developers to users. Accepting such changes demand new standards in evaluating reproduction devices. This paper suggests a new method to evaluate the quality of images, based on cognitive properties of users. The quality of an image is a result oriented from the interaction of various attributes, therefore some functional tests are not enough to evaluate total quality of an image. In this respect, an evaluation model which integrates various physical attributes of an image is needed, that enables a third observer to subjectively evaluate the total quality of an image. In this paper, the experiment was carried out to 127 subjects, with the 84 test stimuli and 11 evaluation factors, followed by an factor analysis. The evaluation factors to assess the quality of images in this paper includes the results by cognitions of users and the properties of reproduction, the factors not only evaluate the quality but suggest how to improve them.

• Proceedings of the Korean Printing Society Conference
• /
• 2000.04a
• /
• pp.35-44
• /
• 2000

Because Image on the CRT change under different illuminants, human is difficult to see original color of object. If what is information of used illuminant on capturing object know, image can be transformed according to viewing condition using the linear matrix method. To know information of used illuminant at an image, the spectral radiance of illuminant can be estimated using the linear model of Maloney and Wandell form an image. And then image can be properly transformed it using color appearance model. In this paper, we predict the spectral radiance of illuminant using spectral power distribution of specular light and using surface spectral reflectance at maximum gray area. and then we perform visual experiments for the corresponding color reproduction according to viewing condition. In results, we ensure that the spectral radiance of illuminant at an image can be well estimated using above algorithms and that human visual system is 70% adapted to the monitor's white point and 30% to ambient light when viewing softcopy images.

• Cartoon and Animation Studies
• /
• s.51
• /
• pp.391-411
• /
• 2018

The purpose of this thesis is to examine ontology of digital photo image based on a Simulacre concept of Gilles Deleuze & Jean Baudrillard. Traditionally, analog image follows the logic of reproduction with a similarity with original target. Therefore, visual reality of analog image is illuminated, interpreted, and described in a subjective viewpoint, but does not deviate from the interpreted reality. However, digital image does not exist physically but exists as information that is made of mathematical data, a digital algorithm. This digital image is that newness of every reproduction, that is, essence of subject 'once existing there' does not exist anymore, and does not instruct or reproduce an outside target. Therefore, digital image does not have the similarity and does not keep the index instruction ability anymore. It means that this digital image is converted into a virtual area, and this is not reproduction of already existing but display of not existing yet. This not-being of digital image changes understanding of reality, existence, and imagination. Now, dividing it into reality and imagination itself is meaningless, and this does not make digital image with technical improvement but is a new image that is basically completely different from existing image. Eventually, digital image of the day passes step to visualize an existent target, nonexistent things have been visualized, and reality operates virtually. It means that digital image does not reproduce our reality but reproduces other reality realistically. In other words, it is a virtual reproduction producing an image that is not related to a target, that is to say Simulacre. In the virtually simulated world, reality has an infinite possibility, and it is not a picture of the past and present and has a possibility as the infinite virtual that is not fixed, is infinitely mutable, and is not actualized yet.