• Title/Summary/Keyword: base tone

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Evaluation of Various Tone Mapping Operators for Backward Compatible JPEG Image Coding

  • Choi, Seungcheol;Kwon, Oh-Jin;Jang, Dukhyun;Choi, Seokrim
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.9
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    • pp.3672-3684
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    • 2015
  • Recently, the standardization of backward compatible JPEG image coding for high dynamic range (HDR) image has been undertaken to establish an international standard called "JPEG XT." The JPEG XT consists of two layers: the base layer and the residual layer. The base layer contains tone mapped low dynamic range (LDR) image data and the residual layer contains the error signal used to reconstruct the HDR image. This paper gives the result of a study to evaluate the overall performance of tone mapping operators (TMOs) for this standard. The evaluation is performed using five HDR image datasets and six TMOs for profiles A, B, and C of the proposed JPEG XT standard. The Tone Mapped image Quality Index (TMQI) and no reference image quality assessment (NR IQA) are used for measuring the LDR image quality. The peak signal to noise ratio (PSNR) is used to evaluate the overall compression performance of JPEG XT profiles A, B, and C. In TMQI and NR IQA measurements, TMOs using display adaptive tone mapping and adaptive logarithmic mapping each gave good results. A TMO using adaptive logarithmic mapping gave good PSNRs.

High Dynamic Range Image Display Combining Weighted Least Squares Filtering with Color Appearance Model (가중 최소자승 필터링과 색 표현 모델을 결합한 넓은 동적 영역 이미지 표현)

  • Piao, Mei-Xian;Lee, Kyung-Jun;Wee, Seung-Woo;Jeong, Jechang
    • Journal of Broadcast Engineering
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    • v.21 no.6
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    • pp.920-928
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    • 2016
  • Recently high dynamic range imaging technique is hot issue in computer graphic area. We present a progressive tone mapping algorithm, which is based on weighted least squares optimization framework. Our approach combines weighted least squares filtering with iCAM06 model. To show more perceptual high dynamic range images in conventional display, we decompose high dynamic range image into base layers and detail layers. The base layers are obtained by using weighted least squares filter. Then, we adopt chromatic adaption function and non-linear compression function to deal with base layers. Only the base layers reduce contrast, and preserving detail. The image quality assessment shows that our tone mapped image is more similar to original high dynamic range image. Moreover, the subjective result shows our algorithm produces more reliable and pleasing image.

A Tone Mapping Algorithm Based on Multi-scale Decomposition

  • Li, Weizhong;Yi, Benshun;Huang, Taiqi;Yao, Weiqing;Peng, Hong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.4
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    • pp.1846-1863
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    • 2016
  • High dynamic range (HDR) images can present the perfect real scene and rich color information. A commonly encountered problem in practical applications is how to well visualize HDR images on standard display devices. In this paper, we propose a multi-scale decomposition method using guided filtering for HDR image tone mapping. In our algorithm, HDR images are directly decomposed into three layers:base layer, coarse scale detail layer and fine detail layer. We propose an effective function to compress the base layer and the coarse scale detail layer. An adaptive function is also proposed for detail adjustment. Experimental results show that the proposed algorithm effectively accomplishes dynamic range compression and maintains good global contrast as well as local contrast. It also presents more image details and keeps high color saturation.

Efficient and Automatic Face Detection Using Skin-tone and Shape (Skin-tone과 특징형태를 적용한 효율적인 얼굴영역 자동검출 기법의 구현)

  • 김광희;김성환;최옥매;이배호
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.575-578
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    • 1999
  • The principal features of a face are as follows : skin-tone, symmetry, and requisites such as shape of ellipse, eyes, nose, mouth. Also, faces have different size, various shape and position. In case of application of face recognition and detection without preprocessing, efficiency of the performance is decreased. In addition, face itself, complex background, image quality, etc. are included. Therefore, previous face recognition methods are implemented on the base of specific constraints of the face image. In this paper, we propose the efficient and automatic face detection algorithm for minimizing influence such as complex background, image quality, etc. This face detection technique consists of skin-tone, candidate face region and face region extractions.

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Manufacture Research of Gradual Standard Color Chart for the Capacity of Reinforcement of Practical Color Coordinate Education (색채활용교육의 역량강화를 위한 단계별 표준색표집의 제작 연구)

  • Lee, Kyung-Hee
    • Fashion & Textile Research Journal
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    • v.13 no.3
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    • pp.332-345
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    • 2011
  • This research designed usable standard color chart which was planned by hue and tone color system. This research studied 5 types standard color chart by designed tone map and preceding research. "Basic Color Chart 14 Colors" was planned for kindergarteners. "Primary Color Chart 63 Colors" was planned for schoolboys. "Middle Grade Color Chart 114 Colors" was planned for junior high school students. "High Grade Color Chart 152 Colors" was planned for senior high school students. "Hue and Tone 205 Colors" was planned for university students and general publics. These 5 types standard color chart were produced the trial color coordinate card and attached the Munsell notation which could reappear the spare color paper when needed. These 5 types standard color chart would be offered the data base for efficient color coordinate education as school age.

Gamma Correction for Local Brightness and Detail Enhancement of HDR Images (HDR 영상의 지역적 밝기 및 디테일 향상을 위한 감마 보정 기법)

  • Lee, Seung-Yun;Ha, Ho-Gun;Song, Kun-Woen;Ha, Yeong-Ho
    • Journal of Korea Multimedia Society
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    • v.19 no.5
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    • pp.837-847
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    • 2016
  • Tone mapping for High Dynamic Range(HDR) image provides matching human visual perception between real world scene and displayable devices. Recently, a tone mapping algorithm based on localized gamma correction is proposed. This algorithm is using human visual properties of contrast and colorfulness with background intensity, generating a weight map for gamma correction. However, this method have limitations of controlling enhancement region as well as generating halo artifacts caused by the weight map construction. To overcome aforementioned limitations, proposed algorithm in this paper modifies previous weight map, considering base layer intensity of input luminance channel. By determining enhancement region locally and globally based on base layer intensity, gamma values are corrected accordingly. Therefore, proposed algorithm selectively enhances local brightness and controls strength of edges. Subjective evaluation using z-score shows that our proposed algorithm outperforms the conventional methods.

How to find a suitable color for you? (본인에게 어울리는 색을 찾는 방법)

  • Jang, Dai-Hyun;Shin, Seong-Yoon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.05a
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    • pp.617-618
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    • 2011
  • Everyone's favorite color that exists naturally or artificially. This paper proposes that ow to find a suitable color for man. First of all, we find out about the base tone forming the color such as skin color, hair color, eye color. Next, we explained color theory of four seasons that color was divided according to skin color, hair color, eye color was diveded by spring, summer, autumn and winter seasons, and according to liking or nature. And look at the characteristics of each season's color.

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Review of Prevention of Hemipelegic Shoulder Subluxation After Stroke (뇌졸중 편마비환자의 견관절 아탈구 예방에 관한 고찰)

  • Han, Jin-Tae;Kweon, Oh-Hyun;Shin, Hyung-Soo
    • Journal of the Korean Society of Physical Medicine
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    • v.2 no.2
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    • pp.243-250
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    • 2007
  • Purpose : Shoulder subluxation is a very common problem in patients with hemiplegia with stroke. Prevention of the low tone subluxed shoulder has been an issue for physical therapists working with neurological patients for many years. Methods : This study reviewed the literature to definite the management and a cause of shoulder subluxation with hemiplegia patients after stroke. Various modalities have been suggested for realigning the glenohumeral joint, but their use is controversial. The purpose of this paper is to review critically the evidence base in order to inform the clinical decision-making process for physiotherapists working in neurology. Results : Literature has identified supports, strapping and functional electrical stimulation(FES) in the management of low tone shoulders. Following review of this evidence it is suggested that there is a lack of reliable and valid research evidence on which to base conclusions. The modalities with the best supporting evidence for realigning the low tone subluxed glenohumeral joint are the triangular sling, Harris hemi sling and the Rolyan humeral cuff used in a standing position and the lap board and arm trough while the patient is sitting. However, due to soft tissue adaptation with associated lack of movement, over-correction and the need for careful patient positioning these supports need to be evaluated for each patient and should be used only in appropriate situations. Conclusion : Similarly, there is a lack of evidence on the effects of long-term use to this equipment. Electrical stimulation is also thought to have potential in the treatment to subluxed low tone shoulders but additional research is required to clarify the parameters for use and the long-term effects of these forms of management.

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A Study on the Environmental color design through the Analysis of Local Colors - Focused on Hongseong-gun - (지역색 분석을 통한 환경색채디자인에 관한 연구 - 홍성군을 중심으로 -)

  • Moon, Sun-Wook
    • Journal of the Korean Institute of Rural Architecture
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    • v.13 no.4
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    • pp.51-58
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    • 2011
  • The purpose of this study was analyzing the features of architectural colors in Hongseong-gun and proposing environmental color design for regional identity color. According to the analysis, Hongseong's base colors are YR of low hue value and grayish tone colors. But a lot of signs and outdoor billboards mar the beauty of the environmental color. So it is more important to solve the problems as well as new environmental color design. The results are as follows; 1) Naepo Color Palette of 2009 Chungnam Public Design Master Plan would be an accepted principal for the contextual landscape image of Chungnam in macro perspective. 2) Outdoor signboards must be controlled and improved for the harmony of the buildings dominant colors. 3) Roof color would arrange R or grayish of deep tone colors those are similar balance of Hongseong base color YR, and gate color would have clear principles of the order such as chromatic or brightness contrast in housing. 4) Forming of future oriented image of Hongseong need to be considered first as to whether it is harmonious tones with existing local base colors.

A Study on the Mixing Capacity of Lifted Flame by the Nozzle Hole-tone of High Frequency in Non-premixed Jet Flames (비예혼합 제트화염에서 고주파수의 노즐 구멍음에 의한 부상화염 혼합성능에 관한 연구)

  • Jo, Joon-Ik;Lee, Kee-Man
    • Journal of the Korean Society of Visualization
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    • v.9 no.4
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    • pp.35-40
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    • 2011
  • An experimental investigation of the characteristic of non-premixed lifted flames with nozzle hole-tone of high-frequency has been performed. Before the fuel was supplied to nozzle, the fuel was supplied through a burner cavity which was located under the nozzle. The fuel passed through the excitation cavity under the influence of the high-frequency affects the lifted flame characteristics. The measurements were performed in flow range that occurs lifted flame and blow out. When the high-frequency is generated from burner cavity, the lifted length became shorter, and noise reduced comparing to unexcitation case. Additionally, operating flow range was increased and diameter of flame base became smaller with high-frequency effect. Through this experiments, it's ascertained that the high-frequency excitation can be adopted with effective method for flame stability and noise reduction.