Nagaaki Ohyama

Bio: Nagaaki Ohyama is an academic researcher from Tokyo Institute of Technology. The author has contributed to research in topic(s): Color image & Image processing. The author has an hindex of 32, co-authored 258 publication(s) receiving 4480 citation(s). Previous affiliations of Nagaaki Ohyama include National Institute of Information and Communications Technology.

Appearance of enhanced tissue features in narrow-band endoscopic imaging.

Abstract: This study was performed to examine the usefulness of medical endoscopic imaging utilizing narrow-band illumination. The contrast between the vascular pattern and the adjacent mucosa of the underside of the human tongue was measured using five narrow-band illuminations and three broadband illuminations. The results demon- strate that the pathological features of a vascular pattern are depen- dent on the center wavelength and the bandwidth of illumination. By utilizing narrow-band illumination of 415630 nm, the contrast of the capillary pattern in the superficial layer was markedly improved. This is an important benefit that is difficult to obtain with ordinary broad- band illumination. The appearances of capillary patterns on color im- ages were evaluated for three sets of filters. The narrow, band imaging (NBI) filter set (415630 nm, 445630 nm, 500630 nm) was selected to achieve the preferred appearance of the vascular patterns for clini- cal tests. The results of clinical tests in colonoscopy and esophagos- copy indicated that NBI will be useful as a supporting method for observation of the endoscopic findings of early cancer. © 2004 Society of

Endoscopic observation of tissue by narrowband illumination

Abstract: We propose a new illumination method for a medical endoscope: narrow band imaging (NBI), in which the spectral bandwidth of the filtered light is narrowed. To confirm how the spectral specifications of the filtered light influence a reproduced image, an experiment was conducted observing the endoscopic images of the back mucosa of a human tongue. In addition, the effect of NBI on endoscopic images was investigated through preliminary clinical tests in colonoscopy and upper gastrointestinal endoscopy. It has been shown that NBI can enhance the capillary pattern and the crypt pattern on the mucosa. These patterns are useful features for diagnosing an early cancer.

Color image processing apparatus

Abstract: A color image processing apparatus reproduces color data of a subject at higher accuracy by estimating the spectral reflectance of the subject from the color chip basis function vn (λ) which can expand the spectral reflectances of all color chips of the reference chart and the expansion coefficients B of the color chips The color image processing apparatus uses an image processing device to which a subject shooting signal Q shot by the color image input device and a reference chart shooting signal G taken from a plurality of color chips each having a spectral reflectance, is known

Color image reproduction based on multispectral and multiprimary imaging: experimental evaluation

Abstract: Multispectral imaging is significant technology for the acquisition and display of accurate color information. Natural color reproduction under arbitrary illumination becomes possible using spectral information of both image and illumination light. In addition, multiprimary color display, i.e., using more than three primary colors, has been also developed for the reproduction of expanded color gamut, and for discounting observer metamerism. In this paper, we present the concept for the multispectral data interchange for natural color reproduction, and the experimental results using 16-band multispectral camera and 6-primary color display. In the experiment, the accuracy of color reproduction is evaluated in CIE (Delta) Ea*b* for both image capture and display systems. The average and maximum (Delta) Ea*b* = 1.0 and 2.1 in 16-band mutispectral camera system, using Macbeth 24 color patches. In the six-primary color projection display, average and maximum (Delta) Ea*b* = 1.3 and 2.7 with 30 test colors inside the display gamut. Moreover, the color reproduction results with different spectral distributions but same CIE tristimulus value are visually compared, and it is confirmed that the 6-primary display gives improved agreement between the original and reproduced colors.

Color reproducing device

Abstract: In a color reproduction device, an input profile that is referenced in converting an input image from an image input device into a device-independent color image is created based on image input device information, shooting- and observation-time lighting data, and subject data, allowing accurate conversion of the input image to the device-independent color image. In reproducing the image by an image output device, the spectral reflectance of the subject itself is calculated from image input device information and shooting-time lighting data, thereby reducing the effect of the shooting-time lighting. The colors of the subject under observation lighting are calculated from observation-time lighting data. A color reproduced image is estimated accurately on the basis of the subject data even if the input image has little information.

Fourier-transform method of fringe-pattern analysis for computer-based topography and interferometry

Abstract: A fast-Fourier-transform method of topography and interferometry is proposed. By computer processing of a noncontour type of fringe pattern, automatic discrimination is achieved between elevation and depression of the object or wave-front form, which has not been possible by the fringe-contour-generation techniques. The method has advantages over moire topography and conventional fringe-contour interferometry in both accuracy and sensitivity. Unlike fringe-scanning techniques, the method is easy to apply because it uses no moving components.

Intelligent electronic appliance system and method

Abstract: An intelligent electronic appliance preferably includes a user interface, data input and/or output port, and an intelligent processor. A preferred embodiment comprises a set top box for interacting with broadband media streams, with an adaptive user interface, content-based media processing and/or media metadata processing, and telecommunications integration. An adaptive user interface models the user, by observation, feedback, and/or explicit input, and presents a user interface and/or executes functions based on the user model. A content-based media processing system analyzes media content, for example audio and video, to understand the content, for example to generate content-descriptive metadata. A media metadata processing system operates on locally or remotely generated metadata to process the media in accordance with the metadata, which may be, for example, an electronic program guide, MPEG 7 data, and/or automatically generated format. A set top box preferably includes digital trick play effects, and incorporated digital rights management features.

Ergonomic man-machine interface incorporating adaptive pattern recognition based control system

Abstract: An adaptive interface for a programmable system, for predicting a desired user function, based on user history, as well as machine internal status and context. The apparatus receives an input from the user and other data. A predicted input is presented for confirmation by the user, and the predictive mechanism is updated based on this feedback. Also provided is a pattern recognition system for a multimedia device, wherein a user input is matched to a video stream on a conceptual basis, allowing inexact programming of a multimedia device. The system analyzes a data stream for correspondence with a data pattern for processing and storage. The data stream is subjected to adaptive pattern recognition to extract features of interest to provide a highly compressed representation which may be efficiently processed to determine correspondence. Applications of the interface and system include a VCR, medical device, vehicle control system, audio device, environmental control system, securities trading terminal, and smart house. The system optionally includes an actuator for effecting the environment of operation, allowing closed-loop feedback operation and automated learning.

Image indexing using color correlograms

Abstract: We define a new image feature called the color correlogram and use it for image indexing and comparison. This feature distills the spatial correlation of colors, and is both effective and inexpensive for content-based image retrieval. The correlogram robustly tolerates large changes in appearance and shape caused by changes in viewing positions, camera zooms, etc. Experimental evidence suggests that this new feature outperforms not only the traditional color histogram method but also the recently proposed histogram refinement methods for image indexing/retrieval.

Secreted and Transmembrane Polypeptides and Nucleic Acids Encoding the Same

Abstract: The present invention is directed to secreted and transmembrane polypeptides and to nucleic acid molecules encoding those polypeptides. Also provided herein are vectors and host cells comprising those nucleic acid sequences, chimeric polypeptide molecules comprising the polypeptides of the present invention fused to heterologous polypeptide sequences, antibodies which bind to the polypeptides of the present invention and to methods for producing the polypeptides of the present invention.