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 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.(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)
—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(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)
A high performance and low power architecture is devised for a 4Mbps infrared wireless communication system dedicated to the mobile computing. In this architecture, 4PPM(4-Pulse Position Modulation) infrared signals detected by an infrared receiver are digitized into TTL interface level pulses, and the digitized pulses are demodulated by a l-bit digital(More)