Norimichi Tsumura

Chiba University, Tiba, Chiba, Japan

Are you Norimichi Tsumura?

Claim your profile

Publications (213)69.99 Total impact

  • Masanori Maki · Ryota Domon · Shoji Yamamoto · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: It is well-known that gloss appearances are observed as the results of association among various physical factors. In order to analysis this association, perception for constancy is very important characteristic features. In this paper, therefore, we verify the influence in gloss and material constancy under the artificial environment by changing the shape and size of light source. We performed two type observations in subjective evaluation, one is the “gloss appearance” which is mainly observed the distribution of specular reflection, and the other is “material appearance” which is mainly observed all distribution of specular and diffuse reflection influenced roughness as whole appearance of object. We prepared two kinds of object which has different roughness, and four kinds of light image generated by LCD projector. A paired comparative experiment was performed under different light source with real object. As the result, there was no obvious gloss constancy when we observed only the distribution of specular reflection, since the shape and size of light source gave a great influence to the gloss perception. On the other hand, an effect of material constancy appeared when we observed all distribution of specular and diffuse reflection influenced roughness as whole appearance of object.
    10/2015; 2015(1).
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we obtain individual difference on variation of melanin component which greatly affect apparent age. We consider frequency of use for UV protection as the factor causing individual difference in aging. It is known that the exposure of UV rays produces melanin pigment in our skin, which promotes aging of a skin such as darkening and unevenness of a skin color. In our previous work, we applied principal component analysis (PCA) to skin color pigmentation distribution and obtained feature values. By changing feature values, we simulated the appearance of human face in arbitrary age. According to this, it is revealed that melanin component in around cheeks especially tends to increase with aging. However, in the previous method, averaged feature values are used for each ages in analysis, and individual difference should be considered at the next step of research. In this paper, we constructed database that have facial image taken in 2003 and 2010 where the same 77 people were subjective. The frequency of use for UV protection was also recorded as lifestyle habit. By applying the same analysis in the previous method, we obtained score shift from the data in 2003 and 2010. From these trends of the shift, we found that one-fourth people can get lightskinned face after 7 years if they use UV protection throughout the year.
    10/2015; 2015(1).
  • Misa Hirose · Mai Kuroshima · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this research, we propose to estimate images of five components that are melanin, oxy-hemoglobin, deoxy-hemoglobin, shading and surface reflection from five band images at the same time. For this purpose, we build nonlinear estimation method by using Monte Carlo simulation of light transport in multi-layered tissue (MCML). The diffuse reflectance of MCML is converted to absorbance using logarithm and the absorbance for each wavelength is defined by a cubic function of chromophore concentration. By using the cubic function, chromophore concentration is determined to minimize residual sum of squares of reflectance. To evaluate the estimation accuracy, we generate numerical phantom of spectral reflectance map. In generating the numerical phantom, we acquire the distribution of chromophore by applying independent component analysis (ICA) to skin color image. The spectral reflectance of MCML is allocated to the obtained chromophore distribution and the reflectance map. As a result of evaluation, our proposed method improved the estimation accuracy significantly.
    10/2015; 2015(1).
  • Kouki Kurita · Taku Yonezawa · Mai Kuroshima · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Non-contact video based heart rate estimation has great various potential in areas such as medical, health care, and affective computing. Recently, the methods using a digital camera for remote heart rate (HR) measurement are widely spread. However, the accuracy of these methods are not sufficient enough to calculate heart rate variability (HRV) accurately. If HRV are measured with high accuracy, we can visualize the sympathetic nerve system by calculating heart rate variability spectrogram (HRVS). In this paper, we propose a method of HR and HRV spectrogram estimation by analyzing extracted hemoglobin concentration from facial color images. Our method does not require any special camera. Furthermore, it is possible to have a stable presumption even under the ambient light sources. As a result, we could obtain 99% accuracy of HR and HRV spectrogram with the same accuracy electrocardiogram. Therefore we succeeded to identify whether participants were relaxed or stressed using conventional DSLR camera.
    10/2015; 2015(1).
  • Norimichi Tsumura · Kaori Baba · Shoji Yamamoto · Masao Sambongi ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract In this article, the authors propose a method to estimate the reflectance property from refocused images from a light source reflected on an object. The blurred information of the light source on the surface of the object is expected to be a practical method to estimate the reflectance property, although various methods have previously been proposed. Because the degree of blurred information is changed with the position of focus in the camera, the authors introduce a light field camera that can change the position of focus after the image is captured. In this research, the authors chose the refocused image where the light source is focused through the reflection on the object surface. Based on the blurred information of the focused light source, they estimate the reflectance property of the object. The estimated reflectance property is applied to inverse rendering for auto material appearance balancing.
    Journal of Imaging Science and Technology 05/2015; 59(3). DOI:10.2352/J.ImagingSci.Technol.2015.59.3.030501 · 0.35 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Tongue diagnosis is a noninvasive diagnosis and is traditionally one of the most important tools for physicians who practice Kampo (traditional Japanese) medicine. However, it is a subjective process, and its results can depend on the experience of the physician performing it. Previous studies have reported how to measure and evaluate the shape and color of the tongue objectively. Therefore, this study focused on the glossy component in order to quantify tongue moisture in tongue diagnosis. We hypothesized that moisture appears as a gloss in captured images and measured the amount of water on the tongue surface in 13 subjects. The results showed a high correlation between the degree of gloss and the amount of water on the tongue surface and suggested that the moisture on the tongue can be estimated by the degree of gloss in a captured image. Because the moisture level on the tongue changes during the course of taking photos, it became clear that we had to wait at least 3 minutes between photos. Based on these results, we established the tongue image analyzing system (TIAS), which can consistently record the gloss and color of the tongue surface simultaneously.
    BioMed Research International 01/2015; 2015:249609. DOI:10.1155/2015/249609 · 1.58 Impact Factor
  • Shinichi Inoue · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this article, the specular reflection phenomenon is analyzed by the concept of the point spread function (PSF). The conventional PSF, which is a sharpness criterion, is used for the transfer function in image science. In general, print (an ink image on paper) is observed as diffuse reflection light, and the light source image, i.e., gloss, is observed as specular reflection. We first introduce the point spread function of specular reflection (SR-PSF). A measurement principle for the SR-PSF is proposed, and a measurement apparatus for the SR-PSF is developed by using a collimator optical system. The experimental results show that the measured SR-PSF works as a transfer function for a specular reflection image. Each detected position is in agreement with the angle of reflected light. The apparatus works as a goniophotometer within a narrow solid angle. The relation between the SR-PSF and the specular reflection angle distribution is discussed in terms of surface geometry. It is concluded that the measured data are the SR-PSF and they have a gonio-reflectance distribution. The reflection angle is caused by the surface normal, and the surface normal distribution can be calculated from the gonio-reflectance distribution by using the mathematical model. We plan to apply our proposed principle to the development of an evaluation technique for the visual gloss. In addition, the high-resolution goniophotometer can be further developed by this measuring technique.
    Journal of Imaging Science and Technology 01/2015; 59(1). DOI:10.2352/J.ImagingSci.Technol.2015.59.1.010501 · 0.35 Impact Factor
  • M. Hirose · S. Toyota · N. Ojima · K. Ogawa-Ochiai · N. Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, principal component analysis is applied to pigmentation distributions, surface reflectance components and facial landmarks in the whole facial images to obtain feature values. Furthermore, the relationship between the obtained feature vectors and age is estimated by multiple regression analysis to modulate facial images in woman of ages 10 to 70. In our previous work, we analyzed only pigmentation distributions and the reproduced images looked younger than the reproduced age by the subjective evaluation. We considered that this happened because we did not modulate the facial structures and detailed surfaces such as wrinkles. By analyzing landmarks represented facial structures and surface reflectance components, we analyzed the variation of facial structures and fine asperity distributions as well as pigmentation distributions in the whole face. As a result, our method modulate the appearance of a face by changing age more appropriately.
    Proceedings of SPIE - The International Society for Optical Engineering 01/2015; 9398. DOI:10.1117/12.2076694 · 0.20 Impact Factor
  • Ryota Domon · Shoji Yamamoto · Kentaro Hikosaka · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a rendering method to reproduce translucent appearances in real-time. Since the translucency is caused by complicated light behavior such as scattering and absorption, reproducing translucent material requires computationally expensive cost. Due to its computational cost, it is difficult to apply the digital mock-up with the computer graphics for the purpose of cost reduction and acceleration of developing products. In order to reproduce the translucent appearance rapidly, we focus on the contrast-reversing image processing. We embed this simple image processing method to the reflection model. Our proposed method can reproduce in real-time with almost the same appearance compared to commercial rendering software.
    11/2014; 2014.
  • Misa Hirose · Yuri Tatsuzawa · Saori Toyota · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this research, we evaluate the visibility of age spot and freckle with changing the blood volume based on the actual facial color images and compare the result with that of pigmentation patterns generated by simulated spectral reflectance. We acquire the concentration distribution of melanin, hemoglobin and shading components by applying the independent component analysis on a facial color image. We reconstruct images by using the obtained melanin and shading concentration and the changed hemoglobin concentration to generate facial images with changing the blood volume. Finally, we evaluate the visibility of pigmentations using these images and compare with the result of pigmentation patterns based on simulated reflectance. In our previous study, we have already evaluated the visibility of pigmentation patterns, and the visibility became lower as the blood volume increases. However, we can see that a specific blood volume reduce the visibility of the actual pigmentations from the result of evaluating the skin color images.
    11/2014; 2014.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Skin is the largest organ of human body which can easily be observed non-invasively, but objective assessment of skin status is difficult. Therefore, we have focused on the oxygen saturation, and proposed the iterative optical path-length matrix method (OPLM) for estimating oxygen saturation of skin. Oxygen saturation of skin may help finding pre-disease state. In Kampo medicine (Japanese traditional herbal medicine), inspection of skin and tongue is one of the principal methods for diagnosis of the state. Kampo medicine contains a number of concepts which are useful for preventive medicine. The Oketsu status is a pathological concept in Kampo medicine, primarily denoting blood stasis/stagnation. In this study, we focused on oxygen saturation of skin as an objective index of skin properties, and studied correlation with the blood flow and the Oketsu score. First, we acquired Oketsu score of the patients, and measured oxygen saturation, hemoglobin concentration and blood flow of the patients at two locations: fingertip of the right first finger and dorsal surface of the right hand. Then, correlation among the values was calculated. As the result, the oxygen saturation showed large correlation with the blood flow and the Oketsu score at dorsal surface of hand. The oxygen saturation of skin will reflect systemic blood flow and Oketsu status, and it would help objective diagnosis by measuring skin color spectrum.
    Artificial Life and Robotics 09/2014; 19(2):170-175. DOI:10.1007/s10015-014-0154-0
  • Kaori Baba · Shinichi Inoue · Rui Takano · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this article, the authors reproduce gloss unevenness on a paper surface by expanding the Torrance‐Sparrow model, which is based on the measurement and analysis of mesoscopic facets on paper. As the conventional Torrance‐Sparrow model only considers macroscopic and microscopic facets, the authors expand the model to be able to consider mesoscopic facets. The normal vectors of mesoscopic facets on a paper surface were measured by using a collimator lens system with a small pinhole aperture, and the authors obtained the normal vector map by moving the stage for the paper. Gloss unevenness was reproduced by generating the same probability distribution as the measured distribution of the normal vectors. As a result, the authors succeeded in reproducing gloss unevenness using an expanded Torrance‐Sparrow model.
    Journal of Imaging Science and Technology 05/2014; 58(3). DOI:10.2352/J.ImagingSci.Technol.2014.58.3.030501 · 0.35 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this article, principal component analysis is applied to pigmentation distribution in the whole face to obtain feature values, and the relationship between the obtained feature vectors and age is estimated by multiple regression analysis to simulate the changes of facial images in women of ages 10 to 80. Since the human face receives more attention than other body parts, a change of a small quantity of the features in a face makes a large difference to its appearance. We can divide the features into two categories. One category is physical features such as skin condition and shape, and the other is physiological features, which are influenced by age and health. In the beauty industry, the synthesis of skin texture is based on these two kinds of feature values. Previous works have analyzed only small areas of skin texture. By morphing the shapes of facial images to that of an average face and extending the analyzed area to the whole face, the authors’ method can analyze pigmentation distributions in the whole face and simulate the appearance of a face as a function of changing the person’s age.
    Biocontrol Science and Technology 03/2014; 58(2). DOI:10.2352/J.ImagingSci.Technol.2014.58.2.020503 · 0.94 Impact Factor
  • Shoji Ezaki · Hiroaki Shimizu · Shoji Yamamoto · Toshiya Nakaguchi · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we propose using earth mover’s distance (EMD) to obtain the appropriate similarity between each histogram for segmentation of abnormal liver regions with mapping of the distances by multidimensional scaling. Conventionally, the similarity between each histogram is calculated by integrating the difference between each bin of the histograms. However, this similarity is unsuitable for appropriate comparison of the histograms because the number of bins for calculating the local histograms of computed tomography images varies. We used EMD to resolve this problem regarding the difference in bin numbers, and the obtained distances are used for mapping the local histograms by multidimensional scaling to low-dimensional space. In the low-dimensional space, the abnormal liver region was well segmented by support vector machine in the test datasets.
    Artificial Life and Robotics 12/2013; 18(3-4). DOI:10.1007/s10015-013-0110-4
  • [Show abstract] [Hide abstract]
    ABSTRACT: We measured the oxygen saturation of skin at various ages by iterating our previously proposed method that can rapidly simulate skin spectral reflectance with high accuracy. Oxygen saturation is commonly measured by a pulse oximeter to evaluate oxygen delivery for monitoring the functions of heart and lungs at a specific time. On the other hand, oxygen saturation of skin is expected to assess peripheral conditions. Our previously proposed method, the optical path-length matrix method (OPLM), is based on a Monte Carlo model of steady-state light transport in multi-layered tissue (MCML), but can simulate skin spectral reflectance 27,000 times faster than MCML. In this study, we implemented an iterative OPLM with a nonlinear optimization technique such that this method can also be used for estimating hemoglobin concentration and oxygen saturation from the measured skin spectral reflectance. The iterative OPLM was over 25,000 times faster than the MCML with 95 % accuracy. Before measurements in clinic, stability of oxygen saturation among measuring pressure was confirmed. Then, the skin reflectance spectra of 72 outpatients aged between 20 and 86 years were measured by a spectrophotometer. Three points were measured for each subject: the forearm, the thenar eminence, and the intermediate phalanx. The result showed that the oxygen saturation of skin remained constant at each point as the age varied.
    Artificial Life and Robotics 12/2013; 18(3-4). DOI:10.1007/s10015-013-0111-3
  • [Show abstract] [Hide abstract]
    ABSTRACT: Since metabolic syndrome is a cause of lifestyle-related diseases, and its early diagnosis and an evaluation of visceral fat are important, this study proposes a new method of estimating the amount of fat. The goal of this study is to estimate visceral fat from estimation of subcutaneous fat and total fat. The subcutaneous fat is estimated from the elasticity of the lumbar area, and the total fat is estimated from body information such as the abdominal vertical and lateral width, and body weight. Finally, the estimated subcutaneous fat is subtracted from the estimated total fat to calculate the visceral fat. Measurement tests conducted to verify the constructed visceral fat estimation model showed good results, with a correlation of 0.96 between the visceral fat area estimated by the proposed method and the actual measured area. The reproducibility of the estimation model was also verified by the cross validation method.
    Artificial Life and Robotics 02/2013; 19(1). DOI:10.1007/s10015-013-0133-x
  • Kimiyoshi Miyata · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: A concept of image quality metamerism as an expansion of conventional metamerism defined in color science is introduced, and it is applied to segment similar color areas in a cultural property. The image quality metamerism can unify different image quality attributes based on an index showing the degree of image quality metamerism proposed. As a basic research step, the index is consisted of color and texture information and examined to investigate a cultural property. The property investigated is a pair of folding screen paintings that depict the thriving city of Kyoto designated as a nationally important cultural property in Japan. Gold-colored areas painted by using high granularity colorants compared with other color areas are evaluated based on the image quality metamerism index locally, then the index is visualized as a map showing the possibility of the image quality metamer to the reference pixel set in the same image. This visualization means a segmentation of areas where color is similar but texture is different. The experimental result showed that the proposed method was effective to show areas of gold color areas in the property.
    Journal of Electronic Imaging 01/2013; 22(1):3029-. DOI:10.1117/1.JEI.22.1.013029 · 0.67 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we apply principal component analysis to pigmentation distribution in whole face and obtain feature values. Furthermore, we estimate the relationship between the obtained vectors and the ages and simulate the changes of women facial image from in her 20s to in her any age by multiple regression analysis. Human faces is the well-known part which receive a lot of attention in the body. Changing the small quantity of the features in faces make large differences in their appearance. The features which we can receive divide broadly into two categories. One is the physical feature such as skin condition and its shape, and another one is the psychological features such as the ages and the health. In the beauty industry it is required to synthesize the skin texture based on the two kinds of the feature values. Previous works remain in the analysis of the skin texture using small area. By morphing shape of facial images to that of average face and extending the analyzed area to whole face, our method can analyze pigmentation distribution in whole face and simulate appearance of face by changing the age.
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this article, we propose a new method—the optical path-length matrix method (OPLM)—as a faster alternative to the Monte Carlo for multi-layered media (MCML), which is often used to simulate the skin spectrum. Theoretically, peripheral oxygen saturation can be estimated by iterating MCML, but it is not a realistic strategy because it requires huge computation time. The optical path-length matrix is obtained as the probabilistic density histograms of the optical path length in skin using MCML, and once the matrix is obtained, skin spectral reflectance can be calculated by accumulating all combinations of elements in the matrix and by setting an absorption coefficient based on the Beer-Lambert law. The computational time of OPLM was approximately 26,000 times faster than that of MCML.
    Optical Review 11/2012; 19(6):361-365. DOI:10.1007/s10043-012-0058-y · 0.66 Impact Factor
  • Ahmed Mahmoud Hamad · Norimichi Tsumura ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Background model updating is a vital process for any background subtraction technique. This paper presents an updating mechanism that can be applied efficiently to any background subtraction technique. This updating mechanism exploits the color and spatial features to characterize each detected object. Spatial and color features are used to classify each detected object as a moving background object, a ghost, or a real moving object. The starting position of each detected object is the cue for updating background images. In addition, this paper presents a hybrid scheme to detect and remove cast shadows based on texture and color features. The robustness of the proposed method and its effectiveness in overcoming challenging problems such as gradual and sudden illumination changes, ghost appearance, non-stationary background objects, the stability of moving objects most of the time, and cast shadows are verified quantitatively and qualitatively.
    Optical Review 05/2012; 19(3). DOI:10.1007/s10043-012-0030-x · 0.66 Impact Factor

Publication Stats

1k Citations
69.99 Total Impact Points


  • 1995-2015
    • Chiba University
      • • Graduate School of Advanced Integration Science
      • • Graduate School of Medicine
      • • Division of Information Sciences
      • • Graduate School of Science and Technology
      • • Department of Information Processing and Computer Science
      Tiba, Chiba, Japan
  • 2003
    • Kao Corporation
      Edo, Tōkyō, Japan
  • 1993
    • Osaka University
      • Department of Applied Physics
      Suika, Ōsaka, Japan