• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.11
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• pp.919-927
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• 2013

In this paper, we present a perception-based tone mapping technique using histogram modification for displaying high dynamic range image. HDR (high dynamic range) tone mapping algorithms are used to display HDR image on LDR (low dynamic rnage) devices. Although perception-based tone mapping methods provides better performance, it dose not always produce good results for a wide variety of images. The proposed method reduces dynamic range by using the perception-based tone mapping function and histogram modification. A derivative of perception-based tone mapping function is used as constraint function of histogram and additional compensation process is performed. This method not only improves contrast by adopting different constraints on each pixel value, but also preserves more visual details. In order to prevent over enhancement, histogram modification technique is applied. Furthermore, it can control the rate of image contrast using control parameters. Subjective and objective evaluations show that proposed algorithm is better than existing algorithms.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.1
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• pp.1-7
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• 2011

In this paper, we propose the digital image enhancement method including local tone reproduction and preservation of the hue. In recent studies, an integrated multi-scale retinex (IMSR) has produced great naturalness in the resulting images through enhancement of visibility in dark area in input images. However, most methods, including IMSR, work in RGB color spaces. As such, this produces hue distortion from the perspective of the human visual system, that is, hue distortion in CIELAB color space. Accordingly, this paper proposes an tone reproduction and enhancement of saturation method in a device-independent color space, CIELAB, to preserve the hue and obtain a high contrast and naturalness. First, to achieve the desired objectives, the IMSR is then applied to only the $L^*$ values in CIELAB color space, normalization, and simple mapping function, thereby preserving the balance of the color components and enhancement of visibility. Then, saturation adjustment is performed by applying the ratio of the chroma variation at the sRGB gamut boundary according to the corrected luminance. In experiments, the proposed method is shown to improve the visibility in dark shadows and bright regions in the resulting images and reduce any color distortion then preference test are performed.

• Journal of Conservation Science
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• v.37 no.5
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• pp.590-605
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• 2021

The history of printing technology in Korea is studied by investigating existing ancient documents and records and comparing accumulated data and knowledge. Cultural property research requires non-destructive testing and observation with the naked eye or aided by a microscope. Researchers' experience and knowledge are required even though they cannot guarantee the outcome. For ancient documents and records that are presumed to consist of woodblock printing, wood type printing, metal type printing, or their combinations, each researcher draws various opinions and conclusions. This often causes confusion and divides the opinions of ordinary citizens and field specialists. Among them, the criteria for judging ancient documents or books printed using woodblock and metal movable material are ambiguous. Academic research on the development history of printing technology in ancient Korea has been stagnant, and conflicts among researchers have also erupted. Involvement of national investigative agencies not specialized in cultural properties has exacerbated the situation. In this study, we investigated printing characteristics that are likely to serve as more objective judgment criteria by quantitatively analyzing the experiments of retrieving several sheets of Korean paper (Hanji) using a replicated Hunminjeongeum (訓民正音) woodblock and quantitatively analyzing the images of the printed papers. In addition, the validity and questions for the typical phenomena presented as a method for distinguishing between woodblock and metal print are reviewed. We investigated the possibility of developing new objective judgement criteria through quantitative analysis using image analysis and investigating the printing characteristics of Korean paper through a reproduction experiment of woodblock printing.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.71-79
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• 2009

We expanded the 3D building information extraction method using shadow and vertical line from single high resolution image with meta information into the method for single high resolution image without meta information. Our method guesses an azimuth angle and an elevation angle of the sensor and the sun using reference building, selected by user, on an image. For test, we used an IKONOS image and an image extracted from the Google Earth. We calculated the Root Mean Square (RMS) error of heights extracted by our method using the building height extracted from stereo IKONOS image as reference, and the RMS error from the IKONOS image and the Google Earth image was under than 3 m. We also calculated the RMS error of horizontality position by comparison between building position extracted from only the IKONOS image and it from 1:1,000 digital map, and the result was under than 3 m. This test results showed that the height pattern of building models by our method was similar with it by the method using meta information.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.6 s.312
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• pp.46-56
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• 2006

In this paper, we propose an improved reproduction algorithm for a realistic image of the real scene based on the optical characteristics of the light sources and the materials at the lighting environment. This paper is continuation of the previous study to improve the modeling method of the light sources and the materials and apply this to the real rear lamp of automobile. The backward ray tracing method is first used to trace the light ray from a light source, and also considers the physical characteristics of object surfaces and geometric properties of light radiation to estimate accurately the light energy incoming toward to human eyes. For experiments and verification of the proposed method, the simulation results are compared with the measured light stimuli. Accordingly, the simulation results show that the proposed algorithm can estimate light energy well and reproduce the visually similar image with a scene incident on a sight of viewer.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.146-154
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• 2010

Argument on the postmodernism of philosophy and history, epic and effect, and culture and art is becoming more ambiguous in scope due to digital technology development. Digital technology makes to change of aesthetic approach over the length and breadth of art and culture including medium art. Analysis of Digital images is changed from presence of images to feature analysis of images which is made by digital technology, and raise the question of how to analyze the images of reproducing digital technology focused on realism. Digital image, focused on hyper reality, should be approached not by film aesthetic approach but by shot unit. Due to emphasizes image reality reproduction by frame unit and not the short unit of the narrative approach, the artistic approach should differ from previous realism practice. Particularly, when considering movies which is focused on illusion, the realistic approach should be realized not in the of realistic approach in narrative aspect but in the aspect of realistic approach in painting aspect.

• Journal of Korean Home Economics Education Association
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• v.9 no.2
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• pp.143-160
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• 1997

The purpose of this study are to analyze the images of‘home life’through the goals of 1st-6th secondary Home Economics education curriculums and to identify the images of ‘home life’held by undergraduate students(83). As results, in the goals of 1st-6th secondary Home Economics education curriculums, 1) the term of ‘home life’is used most frequently, and ‘home life’is confused with ‘daily life’. 2) ‘Home life’is used directly or expressed with clothing life, food life, shelter life, consumer life, etc. in the curriculum goals. 3) ‘Home life’is dealt differently with ‘family life’. 4) The image of “home life”has showed traditional sex role identification. In the replies of undergraduate students, the images are classified with following：1) the images of ‘home’were expressed warmth(hearth), relexation(ease or comfort), sharing, basic unit of society, and conflict and oppression. 2) The images of ‘home life’were expressed hearth, sharing, conflict(interaction), relexation(ease or comfort or sability), routine(act or household art), basic unit(shelter), responsibility and obligation, and reproduction(biological meaning). 3) The images of ‘daily life’were expressed routine(simplicity of boring or routine acts), comfort(stability), oppression, diverse activities in everyday, human relationship, and social life.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.165-171
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• 2005

we can define the procedure of Authoring that it makes area cord and the reproduction prevent menu programmed into MPEG II video stream , Audio which is AC-3 audio stream and subtitle under its own category. And it makes process an attribute, an order and an operation, gives the last disk image (DVD). There are various types of Authoring tools in the market so that authoring tools can enable, encourage, and assist users ('authors') in the selection of tools that produce simple title and video production and editing suites. In this paper, we will compare and analyze authoring process in which image and sound are captured into DVD creation with IEEE 1394port with regard to Window system using generally with Desktop PC and the Macintosh of the PC on the system of Windows and OSX.

• Journal of Korea Multimedia Society
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• v.17 no.7
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• pp.778-786
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• 2014

Buyer-seller watermarking protocol is one of the copyright protection techniques which combine a cryptographic protocol used in electronic commerce with a digital wetermarking scheme aiming at proving the ownership of multimedia contents and preventing the illegal reproduction and redistribution of digital contents. In this paper, it is proposed a new watermarking scheme in an encrypted domain in an image that is based on the block-DCT framework. In order to implement watermarking scheme in a public-key cryptosystem, it is divided that frequency coefficients exist as real number into integer and decimal layer. And the decimal layer is modified integer type through integral-processing. Also, for robustness and invisibility required in watermarking scheme, it is designed a direction-adaptive watermarking scheme based on locally edge-properties of each block in an image through analyzing distribution property of the frequency coefficients in a block using JND threshold.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.705-708
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• 2015

High dynamic range (HDR) imaging is a techniques used in imaging to reproduce a greater dynamic range of luminosity than is possible with standard digital imaging. Tone mapping of HDR images for realistic display is commonly studied. However, scientific visualization of HDR image for analysis of scene luminance has much less attention. In this paper, we present and implement a simple approach for the reproduction and visualization of color information in HDR images. We attempt several simple color visualizing functions, and estimate their effectiveness through the evaluation factors with common HDR images.