The H.264 High Profile video coding scheme is a standard scheme used to encode super high definition videos at a high compression rate.However,as its motion compensation size is very small compared with that of the image resolution of such videos,data related to side information tend to redundant.Therefore,we propose a method that involves extending the macroblock size.This method can be used to enable the scheme to encode super high definition videos more efficiently.Furthermore,we also propose a scheme that uses previously encoded results to decide the appropriate maximum size of the macroblock.

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A conditional access system (CAS) is essential for controlling digital content usage in narrow-band broadcasting such as terrestrial 1-segment broadcasting and digital audio broadcasting.We assume that 'broadcasting receivers' refers not only to mobile phones but also to mobile receivers that do not have two-way communication functions.This would include mobile receivers for use in motor vehicles and portable receivers used in combination with personal digital assistants (PDAs) and portable game stations.A CAS provides a way of restricting broadcasting reception and content playback services to subscribers.To distinguish between subscribers and non-subscribers,contract information needs to be distributed to each receiver,and this needs to be done by broadcasting to mobile receivers.Conventional CASs,i.e.,those used for digital satellite broadcasting,broadcast contract information in this way.Doing this,however,requires a wide transmission band of about 300 kbps because contract information is transmitted to individual receivers.The current technology for distributing contract information on conventional CASs cannot therefore be applied to narrow-band broadcasting.In order to resolve this problem,we have developed a new CAS that is capable of transmitting contract information even in narrow-band broadcasting.We describe the scheme used to calculate the transmission rate of contract information.Furthermore,we have evaluated both the security and the implementation of the proposed CAS and determined that the proposed CAS can be applied to existing services.

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We present an efficient life log system which acts as a personal digital memory.The user's experiences are captured with a wearable video system that has a number of wearable devices such as wearable video cameras,microphones,motion sensors,GPS receivers and body sensors.Our system development is suitable for capturing and retrieving a life log and will thus extend the scope current methods of representing human experiences.We propose making use of media integration and retrieval of various data in order to represent personal experiences.We also propose using wearable video navigation methods to find records of key events that are stored in the wearable video devices.The retrieval scheme is highly flexible and can be used to access and present records of personal experiences in a number of different forms,e.g.,wearable video,ordinary digital video,digital photo,physiological data,and hierarchical ordered electronic document in hierarchical order.Moreover,the system has navigations.Moreover,the system has navigation functions that can be used with the wearable video in order to extract records of key events from the data stored in wearable sensors.This provides a convenient way to retrieve the experiences captured on videos on the basis of the user's location.

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To offer successful streaming video services,the Internet must have some kind of quality of service (QoS) control at each level of the protocol stack.We have investigated fine granular scalability (FGS) with base layer scaling.We conducted an experiment using the double stimulus impairment scale (DSIS) method to assess the usefulness of FGS.A multiple region analysis shows that by using both application-level QoS parameters and the human factor,we can establish QoS mapping between user and application-levels.Furthermore,we show that by using the indicated QoS mapping,the FGS with base layer scaling can be adapted to not only a wide range of channel capacities but also to a wide variety of users.

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We describe the development of a new kind of speech analysis and representation tool,"Speech-ART".The tool presents various parameter-trajectories and several selected frame-parameters together as graphs on fivewindows on a display screen.One of its main features is that users can intuitively select an appropriate analysisframe based on the clear color images(previously developed by us)of phoneme sequences in speech.Moreover,this tool is also suitable for segmenting phoneme sequences from connected speech signals,which is an importantstage in training models used in speech recognition systems,neural networks,and so on.

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