An image coding system includes an optical system 1 , an image pick-up unit 2 , a color space/pixel number converting unit 4 , an orthogonal converting unit 5 , a quantizing unit 6 , a variable run length coding unit 7 and a storing/transmitting unit 10 . The system further includes a code volume control unit 8 for providing, in a first coding process, image data obtained from the color space/pixel number converting unit 4 as a result of omission of at least the color space conversion, among the color space and pixel number conversions, to the orthogonal conversion unit 5 , and computing quantizing coefficient data adequate for obtaining a target code volume from the code volume of coded data provided from the orthogonal converting unit 5 and the target code volume. In a second coding process, the color space/pixel number converting unit 4 executes both of the color space and pixel number conversions and provides resultant image data to the orthogonal converting unit 5 or storage and/or transmission of coded data provided as a result from the orthogonal converting unit 5.

Image coding system

An apparatus and method for obtaining scalability of a video object (VO) whose position and/or size changes with time. The position of an upper layer picture and that of a lower layer picture in an absolute coordinate system are determined so that corresponding pixels in an enlarged picture and in the upper layer picture may be arranged at the same positions in the absolute coordinate system.

Picture encoding and/or decoding apparatus and method for providing scalability of a video object whose position changes with time and a recording medium having the same recorded thereon

A power line communication apparatus capable of performing power line communications with an other power line communication apparatus, the power line communication apparatus, including an authentication processing part which performs an authentication process using at least either an authentication request signal or an authentication response signal with the other power line communication apparatus via a power line, and a signal transmitting part which transmits a predetermined signal to the other power line communication apparatus so that the other power line communication apparatus indicates that the other power line communication apparatus and the power line communication apparatus are made communicatable to each other by the authentication process.

Power line communication apparatus, registration status confirmation method, and power line communication system

A power conversion device includes a power switching circuit that supplies AC voltages generated between switching elements operating as upper arms and switching elements operating as lower arms, and a control circuit that generates and supplies to the driver circuit signals for controlling the switching operation of the switching elements by a PWM method in a first operational region in which frequency of an AC power to be outputted is low, and that generates and supplies to the driver circuit signals for controlling the switching operation of the switching elements at timings based upon the phase of the AC power to be outputted in an operational region in which the frequency of the AC power to be outputted is higher than in the first operational region.

Power Conversion Device

Multilevel converters (MLCs) have emerged as standard power electronic converters in high power as well as quality demanding applications. They are classified into current-fed MLCs and voltage-fed MLCs. Voltage-fed MLCs have widely researched whereas the current-fed MLCs are the recent topic of research. Based on the principle of duality between voltage and current sources, several current-fed MLCs analogous to voltage-fed MLCs have been identified. Current-fed MLCs offer several advantages in terms of high power capability, transformerless operation, short-circuit protection, and excellent quality of output current waveform. The goal of this paper is: 1) to present review of circuit topologies, modulation schemes, and applications of current-fed MLCs; and 2) to review an emerging low-device switching frequency modulation technique known as synchronous optimal pulsewidth modulation for current-fed MLCs. The circuit configuration and advantages of each topology along with various modulation techniques are discussed in detail. Compared to voltage-fed MLCs, the operation of current-fed MLCs need to satisfy additional switching constraints. A survey of classical methods for realization of these operational constraints has been done and a new generalized method has been proposed. Finally, future scope of research has been presented to encourage further development of topologies and modulation techniques for current-fed MLCs.

Current-Fed Multilevel Converters: An Overview of Circuit Topologies, Modulation Techniques, and Applications

In the case of performing self-sustained operation, when power conversion devices supply power to loads, all DC/AC conversion circuits of the power conversion devices are operated in a voltage control mode, and effective voltage (amplitude) of reference AC voltage as a control target for AC power outputted from each DC/AC conversion circuit under voltage control is adjusted in accordance with the power generation amount of a solar panel as a DC power supply, and the state of charge of a storage battery, thereby the amount of power supplied to the loads is controlled.

Power conversion device

When a plurality of storage batteries is used by connecting them in parallel, since the progress of degradation differs among the storage batteries, a power conversion system includes a degradation information acquisition device for acquiring the degradation information of the storage batteries, a temperature information acquisition device for detecting the temperature information of the storage batteries, and a control device for controlling the storage battery power converter based on the degradation information of the storage batteries by the degradation information acquisition device and the temperature information of the storage batteries by the temperature information acquisition device so that the degradation states of the plurality of the storage batteries can be matched.

Power conversion system

A receiving device ( 50 ) is provided to allow appropriate clock regeneration even for a VBR TS when a stream including video and audio data, such as an MPEG2 TS, is transmitted or received in real time through a network having jitter. When the received packet data is stored in a memory ( 53 ) and the packet data is output in accordance with time information added to the received packet data, a clock frequency deviation between a sending device and a receiving device is calculated on the basis of the integration result of the amount of the received packets temporarily stored in the memory ( 53 ), the number of the received packets which have been processed, and the measurement result of the integration time used for integrating the amount of the received packets. A read timing offset of the received packet is obtained on the basis of the calculation result of the clock frequency deviation.

Data receiving device and data receiving method

There is provided a reception device (50) which can perform sufficient clock reproduction even for TS of VBR when transmitting or receiving in real time a stream formed by video/audio data such as TS of the MPEG2 system via a network having a jitter. When packet data received is stored in a memory (53) and the packet data is outputted according to the time information added to the packet data received, the integration result of the reception packet amount temporarily stored in the memory (53), the number of reception packets processed, and the time integrating the reception packet amount are measured and according to the measurement results, a deviation of the clock frequency between the transmission device and the reception device is calculated. According to the result of calculation of the clock frequency deviation, control is performed to obtain the read timing offset of the reception packet.

Data reception device and data reception method

A signal which is to be used in high-speed playback is recorded in a predetermined region of a track. An error correcting check code region for recording an error correcting check code is formed at a position adjacent to the predetermined region. In accordance with the usage, an error correcting check code for high-speed playback, an error correcting check code for normal playback, or predetermined fixed data is recorded in the error correcting check code region. In a digital VTR which records and plays back data at plural kinds of data rates, trick playback data are recorded so that a head scans a subcode area or a VAUX area in high-speed playback at a predetermined tape running speed in each record mode. An area for recording an error correcting check code is used as an area for, in addition to an error correcting check code for normal playback, recording an error correcting check code for trick playback, normal playback data, or trick playback data.

Sadayuki Inoue

Papers

Power conversion device

Power conversion system

Data receiving device and data receiving method

Data reception device and data reception method

Digital signal recording apparatus which utilizes predetermined areas on a magnetic tape for multiple purposes