A scheme for cooperative reception of ISDB-T one-segment service is proposed and its performance is analyzed. It is very difficult to install multiple antennas for diversity reception in small mobile one-segment terminals, and therefore efficient diversity is not always achieved. Cooperative reception between multiple receivers via a dedicated communication network such as Bluetooth is one method of overcoming this problem. Since the communication-link capacity between terminals is limited, a scheme for the efficient exchange of required information such as channel information and sub-carrier data between terminals for diversity must be developed. We discuss possible schemes to reduce the information exchanged between terminals and to achieve maximum diversity performance. Analysis demonstrated the possibility of the proposed scheme for use in a cooperative reception of ISDB-T one-segment service.

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Facial expression recognition has many potential applications in areas such as human-computer interaction (HCI), emotion analysis, and synthetic face animation. This paper proposes a novel framework of facial appearance and shape information extraction for facial expression recognition. For appearance information extraction, a facial-component-based bag of words method is presented. We segment face images into four component regions: forehead, eye-eyebrow, nose, and mouth. We then partition them into 4 × 4 sub-regions. Dense SIFT (scale-invariant feature transform) features are calculated over the sub-regions and vector quantized into 4 × 4 sets of codeword distributions. For shape information extraction, PHOG (pyramid histogram of orientated gradient) descriptors are computed on the four facial component regions to obtain the spatial distribution of edges. Multi-class SVM classifiers are applied to classify the six basic facial expressions using the facial-component-based bag of words and PHOG descriptors respectively. Then the appearance and shape information is fused at decision level to further improve the recognition rate. Our framework provides holistic characteristics for the local texture and shape features by enhancing the structure-based spatial information, and makes it possible to use the bag of words method and the local descriptors in facial expression recognition for the first time. The recognition rate achieved by the fusion of appearance and shape features at decision level using the Cohn-Kanade database is 96.33%, which outperforms the state-of-the-art research works.

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LifeLog data is summarized by extracting the data that has most attracted users from vast amounts of information in the LifeLog data. However, because this information is personal and its characteristics vary from person to person, a new technique for estimating individual user's interests is needed. We propose a method that infers the importance of each LifeLog photo based on the user's photo browsing history. We developped a browsing system that displays photos captured with wearable cameras and records the photo browsing history of the user. Using visual techniques such as HSV histograms and bag-of-features in combination with the RankBoost algorithm enabled us to successfully estimate the importance of unknown photos.

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Future wireless data communications will need an analog-to-digital converter (ADC) that can achieve high sampling rate of more than 100 MS/s as well as high resolution that has sufficiently low power consumption. This brief paper describes a novel digitally assisted ADC suitable for wireless data communications that has been verified by measuring a proof-of-concept chip.

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We describe a mixed reality (MR) environment for testing a novel index of an illusory sense of linear acceleration. The index is based on a measurement of the user's vergence eye movement, which is defined as the simultaneous and collaborative movement of both eyes. For evaluating the illusory sense of linear acceleration, we developed an MR environment consisting of a large hemisphere display and a motion chair, and we conducted eye-movement measurements. In this experiment, subjects sat on a motion chair and were instructed to look around the center of a display. We considered four conditions in a 2 × 2 factorial design with the factors of video motion and chair motion. The video was recorded out of doors by using a car, and the chair was either tilted or not tilted. We observed the significantly faster eye convergence when the video was played (not static) and when the chair was tilted, providing support for the usability of our MR environment.

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