Hiroshi Okumura

Work place: Graduate School of Science and Engineering, Saga University, Saga, Japan



Research Interests: Computer systems and computational processes, Image and Sound Processing, Image Processing, Speech Recognition, Speech Synthesis


Hiroshi Okumura was born at Kyoto, Japan in 1964. He received B.E.S.E. and M.E.S.E. degree from Hosei University in 1988 and 1990, respectively, and Ph.D degree on environmental engineering from Chiba University in 1993. He became a research associate at Remote Sensing and Image Research Center, Chiba University first in 1993. Next, he became a research associateand a lecturer at the Department of Electrical Engineering, Nagaoka University of Technology in 1995 and 2000, respectively. He is now an associate professor at the Department of Information Science, Saga University. His research interests are in image and speech processing and remote sensing.

Author Articles
Image Retrieval Based on Color, Shape, and Texture for Ornamental Leaf with Medicinal Functionality Images

By Kohei Arai Indra Nugraha Abdullah Hiroshi Okumura

DOI: https://doi.org/10.5815/ijigsp.2014.07.02, Pub. Date: 8 Jun. 2014

This research is focusing on ornamental leaf with dual functionalities, which are ornamental and medicinal functionalities. However, only few people know about the medicinal functionality of this plant. In Indonesia, this plant is also easy to find because mostly cultivates in front of the house. If its medicinal function and that easiness are taken into consideration, this leaf should be an option towards the full chemical-based medicines. This image retrieval system utilizes color, shape, and texture features from leaf images. HSV-based color histogram, Zernike complex moments, and Dyadic wavelet transformation are the color, shape, and texture features extractor methods, respectively. We also implement the Bayesian automatic weighting formula instead of assignment of static weighting factor. From the results, this proposed method is very powerful from any rotation, lighting, and perspective changes.

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Image Identification Based on Shape and Color Descriptors and Its Application to Ornamental Leaf

By Kohei Arai Indra Nugraha Abdullah Hiroshi Okumura

DOI: https://doi.org/10.5815/ijigsp.2013.10.01, Pub. Date: 8 Aug. 2013

Human has a duty to preserve the nature, preserving the plant is one of the examples. This research has an emphasis on ornamental plant that has functionality not only as ornament but also as medicine. Although in Indonesia, in general this plant is cultivated in front of the house; only few people know about its medicinal function. Considering this easiness to obtain and its medicinal function, this plant has to be an initial treatment or option towards full chemical-based medicines. This research proposes a system which able to identify properly ornamental plant from its leaf utilizing its shape or color features. Shape descriptor represented by Dyadic Wavelet Transformation and Zernike Complex Moment, and HSV-based color histogram as color descriptor. This research provides benefit of these three methods to solve various test aspects. It was obtained 81.77% of overall average-testing performance.

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