Hiroyuki Okuhata

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A l o w-p owe r p r o ce ss o r ar c h ite c t ur e i s d e s c r i b e d d e d i c a t e d l y fo r e m b e d d e d a p p l i c a t i o n p r o g r a m s by me a n s o f a n o b j e c t c o d e c o m p r e s s i o n a p p r o a c h .T h i s a p p r o a c h u n i e s d u p l i-c a t e d i n s t r u c t i o n s e x i s t i n g i n t h e e m b e d d e d p r o(More)
In this paper, we present an FPGA implementation of real-time Retinex video image enhancement. Our implementation is based on the previously proposed architecture, which can handle the variational approach of the Retinex theory. In order to efficiently reduce the enormous computational cost required for image enhancement, processing layers and repeat counts(More)
In this paper, we propose a novel halo reduction method for variational based Retinex image enhancement. In variational based Retinex image enhancement, a cost function is designed based on the illumination characteristics. The enhanced image is obtained by extracting the illumination component, which gives minimum cost, from the given input image. Although(More)
We have developed a real-time vital signs monitoring system for two years in 2012 and 2013. Just by putting a single vital sensor node to the back waist position of each player and placing four data collection nodes around a field, the system can monitor at a note PC heart rate (HR), energy expenditure (EE) and body temperature (BT) for all players during a(More)
In order to plan effective training menus and avoid injuries and diseases, vital signs monitoring for athletes during training and game is essential, where a key issue is how to collect vital data reliably and in real-time from many people spread in a large field. To realize such a real-time vital data monitoring system, we developed prototype wireless(More)
Heart rate sensing can be used to not only understand exercise intensity but also detect life-critical condition during sports activities. To reduce stress during exercise and attach heart rate sensor easily, we developed a clip-type photoplethysmography (PPG)-based heart rate sensor. The sensor can be attached just by hanging it to the waist part of(More)
Real-time vital data monitoring for athletes during training and game is essential for planning effective training menus and avoiding injuries and diseases. Especially for team sports such as footfall and rugby, how to reliably collect vital data from many players spread in a large field is a key issue. In our previous work [1], we developed a real-time(More)
—A VLSI implementation of the H.324 audiovisual codec is described. A number of sophisticated low-power archi-tectures have been devised dedicatedly for the mobile use. A set of specific functional units, each corresponding to a process of H.263 video codec, is employed to lighten different performance bottlenecks. The H.324[1] international standard(More)
In this paper, we present a computational cost analysis result of accelerated iterative shrinkage smoothing algorithm, which is one of promising image smoothing algorithms with sufficient smoothing quality results and reduced processing time. The main motivation of this cost analysis is to provide a base for efficient hardware implementation. We implemented(More)