||Computer Science, Information Technology
|| My specialty is digital signal processing (DSP). DSP applications include audio and speech processing, sonar, radar and other sensor array processing, statistical signal processing, digital image/video processing, video coding, audio coding, image compression, signal processing for telecommunications, control systems, biomedical signal processing. Among them, I am interested in research on color image processing and biomedical signal processing. Since the color image signal processing was performed using the gray-scale image signal processing method, there is little research on a unique processing method for the color image signal. Since the color image signal is a multi-channel signal, the processing methods for the color image signal such as the processing using the correlation between channels and the processing for converting the color space have been clarified. My research also includes research on color image signal processing based on human color perception. In biomedical signal processing, I am conducting research on EEG analysis and biometric authentication using iris images.
The type of research is to propose novel signal processing algorithms. Research results are clarified through presentations at international conferences and publications in journals. More than 150 papers have been published in journals.
|Research Field(Keyword & Summary)
- (1) Color/gray-scale image enhancement
This research aims to improve the image quality of images with insufficient contrast and blurred images. In gray-image processing, the research gives methods for finding the gray-scale transformation function, and I have realized the derivation of the optimum function using the genetic algorithm. In color image processing, a lot of color image enhancement methods based on human color perception have been proposed.
- (2) Underwater image processing
Light scattering and absorption of light in water cause underwater images to be poorly contrasted, haze and dominated by a single color cast. A solution to this is to find methods to improve the quality of the image that eventually leads to better visualization. We propose an integrated approach using Adaptive Gray World (AGW) and Differential Gray-Levels Histogram Equalization for Color Images (DHECI) to remove the color cast as well as improve the contrast and colorfulness of the underwater image.
- (1) Color conversion formula with saturation correction from HSI color space to RGB color space, IEICE Trans. on Fundamentals, Vol.E104-A, No.7, July 2021.
- (2) Underwater image enhancement by adaptive gray world and differential gray-levels histogram equalization, Advances in Electrical and Computer Engineering, Vol.18, No.2, July 2018.
- (3) Color Image Enhancement Method with Variable Emphasis Degree, IEICE Trans. on Fundamentals, Vol.E101-A, No.4, April 2018.
- (4) Hue-Preserving Color Image Processing with a High Arbitrariness in RGB Color Space, IEICE Trans. on Fundamentals, Vol.E100-A, No.11, November 2017.
- (5) HSI Color Space with Same Gamut of RGB Color Space, IEICE Trans. on Fundamentals, Vol.E100-A, No.1, January 2017.
- (6) Improvement of the solving performance by the network of particle swarm optimization, IEICE Trans. on Fundamentals, Vol.E98-A, No.8, August 2015.
- (7) A novel method for design of gray-level transformation functions for image contrast improvement based on the histogram equalization technique, Electronics and Communications in Japan, Vol.96, No.7, July 2013.
- (8) Bit-length expansion for digital images, Electronics and Communications in Japan, Vol.92, No.10, July 2009.
- (9) Enlargement for Images with Gaussian Noise by Embedded Filtering in the LP Algorithm, IEICE Trans. on Fundamentals, Vol.E89-A, No.8, August 2006
- (10) A Novel Structure of LWOS Filters Based on Threshold Decomposition, IEEE Trans. on Circuits and Systems II, Vol.48, No.9, September 2001.
- Nothing special
||IECE Special Achievement Award(2004), IEICE Educational Achievement Award (2020)
|Grant-in-Aid for Scientific Research Support: Japan Society for Promotion of Science (JSPS)
|Research Grants/Projects including subsidies, donations, grants, etc.
|Recruitment of research assistant(s)
|Affiliated academic society (Membership type)
||(1) IEEE (Senior member)
(2) IEICE (Fellow)
|Education Field (Undergraduate level)
||System analysis, Digital signal processing, Basic logic circuit, Information mathematics
|Education Field (Graduate level)
||Advanced Signal processing