• Title/Summary/Keyword: Low tone

Search Result 301, Processing Time 0.025 seconds

Block Based Efficient JPEG Encoding Algorithm for HDR Images (블록별 양자화를 이용한 HDR 영상의 효율적인 JPEG 압축 기법)

  • Lee, Chul;Kim, Chang-Su
    • Journal of IKEEE
    • /
    • v.11 no.4
    • /
    • pp.219-226
    • /
    • 2007
  • An efficient block based two-layer JPEG encoding algorithm is proposed to compress high dynamic range (HDR) images in this work. The proposed algorithm separates an input HDR image into a tone-mapped low dynamic range (LDR) image and a ratio image, which represents the quotients of the original HDR pixels divided by the tone-mapped LDR pixels. Then, the tone-mapped LDR image is compressed using the standard JPEG scheme to preserve backward compatibility and the ratio image is encoded to minimize a cost function that models the perception of each block with different quantization parameters in the human visual system (HVS). Simulation results show that the proposed algorithm provides better performance than the conventional method, which encodes the ratio image without any prior information of blocks.

  • PDF

A HDR Up-scaling Algorithm Using Undecimated Wavelet Transform and Retinex Method (비간축 웨이브릿 변환과 레티넥스 기법을 이용한 HDR 업스케일링 알고리즘)

  • Han, Kyu-Phil
    • Journal of Korea Multimedia Society
    • /
    • v.25 no.10
    • /
    • pp.1395-1403
    • /
    • 2022
  • Lately, over 4K high definition and high dynamic range (HDR) display devices are popularized, various interpolation and HDR methods have been researched to expand the size and the dynamic range. Since most of the legacy low resolution (LR) images require both an interpolation and a HDR tone mapping methods, the two processes should be subsequently applied. Therefore, the proposed algorithm presents a HDR up-scaling algorithm using undecimated wavelet transform and Retinex method, which transfers a LR image of low dynamic range (LDR) into the high resolution (HR) with HDR. The proposed algorithm consists of an up-scaling scheme increasing the image size and a tone mapping scheme expanding the dynamic range. The up-scaling scheme uses the undecimated version of the simplest Haar wavelet analysis for the 8-directional interpolation and the change region is extracted during the analysis. This region information is utilized in controlling the surround functions' size of the proposed tone mapping using MSRCR, to enhance the pixels of around the edges that are dominant feature of the subjective image quality. As the results, the proposed algorithm can apply an up-scaling and tone mapping processes in accordance with the type of pixel.

Physiologic state and behavioral response to sponge bathing in premature infants (스폰지 목욕에 대한 미숙아의 생리적상태 및 행동반응)

  • Lee Hae Kyung;Hong Kyung Ja;Nam Eun Sook;Lee Young Hee;Jung Eun Ja
    • Child Health Nursing Research
    • /
    • v.6 no.1
    • /
    • pp.32-50
    • /
    • 2000
  • A descriptive exploratory design was used in this study to evaluate the effects of sponge bathing on physiological(heart rate, heart period, vagal tone, oxygen saturation, respiration) and behavioral responses in newly born 40 preterm infants from intensive care unit of S University Hospital in Seoul. Data has been collected from October, 1997 to March, 1999. The infants were between 27-33 weeks gestational age at birth, and were free of congenital defects. The subjects entered the protocol when they were medically stable (determined by initiation of feeding and discontinuation of all respiratory support) but still receiving neonatal intensive care. The infants' physiologic parameters were recorded a 10 - minute before, during, and after bathing. Continuous heart rate data were recorded on a notebook computer from the infant's EKG monitor. The data were digitized off-line on software(developed by Lee and Chang in Wavelet program) which detected the peak of the R wave for each heart beat and quantified sequential R-R intervals in msec(i.e. heart periods). Heart period data were edited to remove movement artifact. Heart period data were quantified as : 1) mean heart period; 2) vagal tone. Vagal tone was quantitfied with a noninvasive measure developed by Porges(1985) in Mxedit software. To determine behavioral status, tools were developed by Scafidi et al(1990) were used. Collected data were analyzed with the SPSS program using paried t-test, ANOVA, and Pearson correlation. The result were as follow. 1. The results of the ANOVAs indicated that vagal tone were signifcantly lower during bathing than baseline and post-bathing. There were significant differences in heart period and heart rate levels across the bathing. But the mean oxygen saturations and respirations were no differences. Also, there were no significant differences on behavioral sign, motor activity, behavioral distress, weight changes, morbidity, and hospitalization period. 2. To evaluate the relation between vagal tone and subsequent parameters, the two groups (the high group had 19 subjects and low group had 21subjects) were divided by the mean baseline vagal tone. Vagal tone measured prior to bathing were significantly associated with respiration before bathing, vagal tone during bathing, and the magnitude of change in both vagal tone. But, other subsequent reactivities were no differences in two groups. 3. Correlations were also calculated between vagal tone and the subsequent physiological reactivities from baseline through after- bathing. Correlations were significant between baseline vagal tone and baseline heart rate, between baseline vagal tone and baseline heart period, between baseline vagal tone and oxygen saturation after bathing. In summary, the bathing in this study showed a stressful stimulus on premature infants through there was significance in the physiological parameters. In addition, our study represents the documentation that vagal tone reactivity in response to clearly defined external stimulation provides an index of infant's status.

  • PDF

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
    • /
    • v.2 no.2
    • /
    • pp.243-250
    • /
    • 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.

  • PDF

Characteristics of Plane Impinging Jets(1) - Slit-tone - (평면 충돌제트의 불안정 특성(1) -슬릿음-)

  • 권영필
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.14 no.1
    • /
    • pp.50-55
    • /
    • 2004
  • In this study, slit-tones by plane impinging jet are investigated experimentally over the whole subsonic flow range, especially at low speeds, in order to obtain the instability behaviour of impinging plane jet. Slit-tones are generated at low speeds associated with laminar shear layer instability as well as at high speeds associated with turbulent instability. Most of low-speed slit-tones are induced by symmetric mode instability unless the slit is not so wide, in which case antisymmetric modes are induced like edge-tones. It is found that the frequencies at low speeds ate controled by the unstable condition of the vortex at the nozzle exit and its pairings by which the frequencies are decreased by half. In the case of symmetric modes related with low-speed slit-tones, frequencies lower than those associated with one-step pairings are not found.

Color Measurements and Colorimetric Analysis of Reproduced Colors with the Weighted-Ordinatc Method (분광측색법에 의한 색인쇄물의 측색 및 해석)

  • 이상남
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.2 no.1
    • /
    • pp.1-21
    • /
    • 1984
  • Reproduced colors which are half-tone dot printed at the rate of 10, 20, 30, 100% half-tone dot area by each process ink-cyan, magenta and yellow ant at the rate of 10, 20, 30, 100% by the mean color mixing of black, cyan, magenta and yellow, are colorimetric analyzed by make use of the 1931 CIE XYZ system of color specification and matching the Munsell color system. With increased half-tone areas, 1. Yellow has ideal reflectance curve, but magneta has nonideal reflectance curve. 2. Yellow and cyan have almost standard dominant wavelengths but magenta has complementary wavelengths. 3. Yellow has higher excitation purities in primary colors, but low excitation purities in secondary and third colors. 4. Value function is decreased and generally the range of value function in chromaticity diafgram is extented. 5. The properties of black and CMY printed materials have not equality, therefore black process ink is necessery in half-tone printing process.

  • PDF

Genetic Algorithm based Tone Injection PAPR Reduction (유전자 알고리즘을 이용한 톤 삽입 PAPR 감소 기법)

  • Park, Soon-Kyu;Choi, Joo-Pyoung;Lee, Won-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.34 no.1C
    • /
    • pp.98-104
    • /
    • 2009
  • Tone injection scheme has been known as one of PAPR(Peak to Average Power Ratio) reduction methods deployable to multi-carrier system like OFDM(Orthogonal Frequency Division Multiplexing). The basic idea in tone injection scheme is to enforce the constellation size larger so that each of original constellation points is mapped into the preassigned distinct points. Along the accomplishment of tone injection, it needs great amount of computations to search out not only an appropriate frequency but a phase. Although there is no loss of transmission rate is expected because of no need to send the overhead, the tone injection scheme has not been preferable due to its enormous computations. To alleviate the amount of complexity, this paper proposes the GA(Genetic Algorithm) based tone injection scheme such that its complexity is reduced comparing with that of the conventional method. The simulation results show that the proposed GA based tone injection scheme approaches the PAPR performance associated with the conventional exhaustive search method at the expense of low computations.

Efficient Reverse Tone Mapping Method Using Guided Filter (Guided Filter를 사용한 효율적인 Reverse Tone Mapping 기법)

  • Kim, Sang Hyub;Lee, Chang Woo
    • Journal of Broadcast Engineering
    • /
    • v.23 no.2
    • /
    • pp.283-292
    • /
    • 2018
  • Devices capable of capturing and displaying high dynamic range (HDR) images with significantly increased brightness range compared to low dynamic range (LDR) images have been developed and various methods for efficiently converting the brightness range of an image have been developed. In this paper, we propose a reverse tone mapping method using a guided filter to efficiently convert LDR images into HDR images. After obtaining brightness enhancement function (BEF) using a guided filter, we can reconstruct HDR image from one LDR image. In addition, when the image is too bright or dark, the proposed method maximizes the image quality of the reconstructed HDR image by estimating and adjusting the exposure value before expanding the brightness range of images. Computer simulations show that the proposed method produces HDR images of superior quality compared with the conventional methods.

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)
    • /
    • v.9 no.9
    • /
    • pp.3672-3684
    • /
    • 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.

A Differences in Preference and Evaluation on the Image of Make-up (Part II) -Focused on Perceiver's Age & Habitant- (화장색 이미지평가와 선호도 차이 (제2보) -지각자의 연령과 거주지를 중심으로-)

  • Lee Yon-Hee
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.30 no.5 s.153
    • /
    • pp.684-698
    • /
    • 2006
  • This study consists of the stimuli of a female model in her twenties with twenty-two different facial make-up. The subjects of this study are one thousand low hundred ninety seven purposive sampled-male and female grown-ups throughout the country. The period of the research was the December of 2004, one month, and the materials were analyzed by factor analysis, T-examination, analysis of variance, Cronbach's a, Duncan's Multiple Range Test. Here follows the result of the research. Firstly, Familiarity, Intelligence, Fitness, Charm, Tradition and Youth were came out as the result of factor analysis of make-up color image perception. Secondly, in age/lip color perception of bright skin tone, there was difference of Intelligence and Charm. In age/image make-up perception of bright skin tone, there was difference of Familiarity, Charm especially on Cool image make-up. Thirdly in habitant/lip color perception of dark skin tone, there was difference of Intelligence and Charm. In habitant/image make-up perception of bright skin tone, there was difference of Familiarity, Charm and of bright skin tone, Intelligence, Charm, Tradition and Youth. Fourthly, there were the interaction effects on the gender of perceivers and lip color and image make-up of perceivers habitant. Lastly, in preference rate, lip color was more affected by age and image make-up were more affected by perceivers habitant.