In MC DCT coding such as MPEG-2,a sophisticated quantization scheme is realized considering human visual perception system (HVS). However, this HVS is only for spatial directions and a temporal direction has never been considered. To cope with this problem, we have designed the non linear counter MAXwise quantizer in which noise can be weighted by HVS in a temporal direction.

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JPEG Spatial mode is known as reversible coding scheme for natural images. This scheme is based on Differential Pulse Code Modulation(DPCM), however that is not so effective because of fixed prediction. In this paper, we propose a reversible coding method for natural images. Fixed or adaptive prediction is used according to states of absolute difference value among neighboring pixels in our method. The prediction equation which gives the minimum entropy of prediction errors is used in fixed prediction mode, where as the prediction equation which gives the minimum power of prediction errors at the neighboring pixels is used in the adaptive prediction mode. Simulation results for the images of 256 levels show that the proposed method can reduce the entropy by an average of 5.73 percents compared with the JPEG Spatial mode.

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This paper addresses adaptive variable length coding (VLC) method to improve coding efficiency. This method periodically redesigns VLC table using formerly coded data. Simulation results show the effectiveness of the method.

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The block discrete cosine transform (DCT) is by far the most widely used transform for the compression of both still and sequences of images. However, by means of this technique, particularly for high compression ratios, so called blocking artifact arises as one of the most typical and annoying artifacts that affect images. In this paper, a method for the reduction of blocking artifact in images coded at very low bitrate is presented. We utilize maximum a posteriori (MAP) estimation and projection onto convex sets (POCS) iterative restoration to remove the blocking artifact and improve signal to noise ratio (SNR). Combined with our renovated DCT coefficient constraint, image quality improvement of 0.5〜1.6dB in terms of SNR is obtained.

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This paper proposes a low buffer delay encoding/decoding method by restricting bit distribution in a picture. If bit distribution of coded data in a picture is restricted as proposed in this paper, it is possible for encoder to start sending the bitstream before finishing encoding a picture, and also possible for decoder to start decoding the bitstream before finishing receivinga picture. The proposed method can reduce an encoding/decoding buffer delay to less than a picture interval.

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[in Japanese]

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A new architecture to develop a remote video duplication system for high-quility digital VCR is proposed. The proposed system can work on any best-effort type networks to transmit AV signals with no or very little compression noise in semi-real-time operation. The system is featured by an intelligent transmission control mechanism. System operation focused on the buffer transition is also analyzed in this paper.

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A highly reliable and robust transmission protocol for a digital VCR remote duplication system is proposed. Requirements for the protocol are a high throughput, perfect error correction and an ability of re-transmission from an interruped point due to a line trouble. In this protocol, SSCOP and VFTP and employed to achieve them, where VFTP is a specially designed protocol for efficient recovery of large video data.

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We created an active linkage between NTV's Internet home page and the live broadcast of the "HAKONE EKIDEN" using the MESOC system, which monitors the athletes' progress and in real-time automatically relays it to the Internet.

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In Fuji Television's new broadcast center, the Wavelength-Division and Time-Division hybrid multiplexed (WD/TD) optical network has been practically implemented. This paper describes the system requirements, the structure, and the features of this optical network.

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In Fuji Television's new broadcast center, the Wavelength-Division and Time-Division hybrid multiplexed (WD/TD) optical network has been practically implemented. This paper describes the system design and development of this optical network.

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This system is a simplified and interactive homenetwork system used to transmit the NTSC video and audio signal, which is generated from a digital broadcasting receiver, DVD players and so on, to distant place. And the way is that its signal is multiplexed in the frequency for the current broadcasting wave gotten from receiving antenna terminal, after it's changed to a television frequency band by television modulator and up-convertor. With this system, a family can share multimedia pictures, soureces and others by easy operation.

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Some image output devices, such as some printers, are bilevel representation equipments. When they are exchanged among different output devices, it is necessary to convert the resolution of images. The subsampling method is widely used as the resolution conversion method of digital image is different from other bilevel images in statistical character. This paper proposes the resolution conversion method of dithered images. In our scheme, at first, a multilevel image is prepared by applying the lowpass filter for the original dithered image. Secondly, a resolution conversion process is applied for the prepared multilevel image. Finally, dithering process is applied for the obtained image. Simulation results show that our method is effective for resolution conversion of a dithered image.

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An image enhancement method based on multi-scale wavelet representation is discussed. The edge enhancement is controlled by the relation between neighboring structures and regularity across scales of wavelet transform. This method offers flexibility to selectively enhance edges and ability to control noise magnification.

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To create images is a main theme in the field of computer graphics. In this report, We generate handwritten like image by analysis an original image. We consider basic feature of handeritten image such as to detect directions of the contour of objects. Based on the detected direction and multiscale expression we generate handwritten image.

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This report is the construction method of PC-LAN for Video Transmission. We use 100VG-AnyLAN and PC card Type MPEG-2 Encoder & Decoder (SP@ML). The system has 12channel at 7Mbps, low delay (7FRAMES), real-time transmission. We care the CPU performance for PCE BUS by Bus Mastering and Hardware Filtering at NIC.

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The DVC client-server system on the ATM network makes it possible to transmit real time video signal of the DV format and to compose non-linear editing. This system will provide not only a new method of news gathering, but emergency information support in the case of any disaster.

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We are continuing to investigate desk-top program production (DTPP) with the aim of implementing a next-generation program production environment. In this paper, we propose a DTPP-based hierarchical program production method that supports a full range of production capabilities including the editing and rearrangement of program data obtained by regular broadcast program production processes, the assignment of relations among the various individual data, and the ability to save the data while preserving the assigned relations. This method greatly simplifies the process of producing multimedia programs based on regular broadcast program data.

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In this paper we propose a new image expression environment IE Room (Image Expression Room). The system which consists of a chroma-key studio and a large screen with a half mirror provides the environment where a user can see himself in some scene on a screen like a real mirror. It can helo people that do not have expert knowledge on the technique of expression to express their images with a high degree of freedom.

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In this paper, we propose a hand shape recognition approach based on the hidden Markov model. This approach uses one dementional feature pattern derived from a radius sequence from the center of gravity to the edge in a silhouette image.

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When objects are separated from a background, blue screen is often used. However, this technique requires large studio sets. In this paper, we propose that separation of objects from a background using a closing technique in Morphology. We implement a Virtual Camera System as one application using this method.

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In this paper, first we summarize our various methods for arbitrarily focused image reconstruction. And then we propose a new method using analysis of camera features, relation between camera parameters and PSFs. We describe the analysis method and sysnthesize our desired arbitrarily focused images based on the analysis.

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This paper discribes a method of estimation for motion vectors based on perspective projection by using the measured camera parameters. The result showed that this method is more effective than block matching method in the area where the luminance of moving image is smooth.

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We formerly reported on a method which extracted 3-D information from image sequence by using reliable characteristic points. This paper proposes a new technique which obtains initial values of rotation parameters previous to carrying out the above method in order to separate accurately a motion of an object into translational and rotational components. In addition, this paper describes acquisition of deep information on characteristic points which do not have high reliability.

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In the conventional intersection voting method for 3-D measurement, positions of intersections must be calculated concerning all the combinations of the feature points on image sequence. To reduce the amount of computation required for calculating intersections, this paper proposes a new method which partitions the image into subblocks and detects a motion vector in each subblock. By applying individually the above voting method to each set of subblocks which correspond to one another in the image sequence, computation load can decrease remarkably.

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[in Japanese]

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This paper proposes a new technique for precision template matching, wherein the translations between the input image and the template are detected with fractional pixel resolution. Assuming the band-limited interpolation model, several equations and their approximations are derived for one- and two-dimensional template matching cases.

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A ghost interference was caused by Akashi Kaikyo Bridge when its hunger-ropes were under construction as the first case in japan. We simulated the interference by original program for hunger-ropes of suspension bridges. This paper presents the simulation and a result of field verification test we have confirmed fits for the simulation.

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We propose a complex limiter method for the interference reduction TV receiver using digital signal processing technique. The interference is caused by Sporadic-E ionospheric propagation. As the result of simulation experiments, this method has good accuracy with small table memory.

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We started NHK-Character Multiplex Broadcast on MARCH 22,1996. As we start the broadcast, we investigated the recieving conditions in the field. In this paper, we will report how the quality of the multiplexed signal drops in the broadcasting.

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This paper is survey report about interference for adjacent-repeater station in set up the new 10kW FM broadcasting transmitter site.

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Auther paid attention to common mode which is considerered to be one of interference of reception, we succesfully prevented of TV interference by attaching a ferrite core to a coaxial cable.

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We developed a new head-end for CATV system. Its receiving equipment consists of only passive devices (including optical waveguide modulators), therefore we needs no power supply to the receiving point. By use of optical fiber this head-end enables non-relay transmission from the receiving equipment to the head-end and is effective in prevention of lightning damages.

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A new multiplexing method of channel low-speed managing data for high-speed DPSK coherent optical multichannel communication systems is proposed. The transmitter laser diode is frequency-modulated by a carrier modulated by the data. 64kbps data can be transmitted.

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We have developed RGB signal infrared connection unit which can be used to connect a PC and a display device such as a projector. The connection unit consists of a transmitter and a receiver. It enables the sending of a full color RGB signal (VGA mode, 640^*480 dot) over a maximum of 5 meters.

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This paper describes features and outlines of a high efficiency 20kW digital AM radio transmitter. We developed a high efficiency power amplifier and a high efficiency power supply fo the transmitter. The measured overall efficiency was over 84 percent at 1.15MHz.

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This paper examines a design method of FIR filter equalizer for TV excitor. In this method, filter corefficients are calculated using IFFT and adaptive algothism.

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This paper describes the structure of Exciter system to achieve the non-interruptive TV transmitting system for University of the air foundation.

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This paper describes a new control unit for transmitter. Control unit has microprocessor. This control unit is intelligent.

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This paper describes a new getting analog data circuit for power amplifier. We can get data of power amlifier (transistor current, output power, power supply voltage) very easily by this circuit.

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We developed a mobile digital SNG. We load this equipment into a car or a ship, and can transmit the digital signal into a CS even though the car or the ship is moving. The digital signal is an NTSC or an HDTV one. The tracking scheme used both the monopulse tracking and the attitude heading reference system. Using this equipment, we transmitted a live program for about 23 hours.

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This paper describes the results of the simulation of multi-carrier transmission via satellite. The digital video compression technology enables to send two or more programs using one transponder. Multi-carrier transmission causes the inter-modulation by each carrier because of non-linear effect of TWT.

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We present a noise reduction adapter for DBS reception using a practical MSW signal-to-noise enhancer operated in the BS-IF band. The compact adapter (50×75×30mm^3) simultaneously achieved 2 to 7dB noise reduction of NTSC video signals for all channels in the BS-IF band.

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At present, the small aperture antennas is used for broadcasting satelite. The carrier to noise ratio is used for the video reception quality evaluation. It is influenced by meteorological phenomena and in particular at the time of rainfall. While on the other hand the plane type antenna is influenced by night dew. The behavior of the variation of the CN ratio characteristics caused by propagation conditions has been studies.

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Although pulse code modulation (PCM) sound broadcasting employs low-power transmission, it can provide better reception with a small aperture antenna. However, to achieve good quality PCM sound broadcasting, we have to understand more about the relation between bit-error rate and propagation characteristics of signal received from the satellites. In this paper, we will report the relation between propagation characteristics and the bit-error rate of the digital signal from the JCSAT-2 communication satellite using the 12GHz frequency range.

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This short paper says regarding radiation patterns of 4L-polyloop antennas with finite reflector, more precisely than previous thesis. We have obtained the most important result from the cascaded hexagonal antenna in the case of a λ/5 long common line between the adjacent loops. The half-power beam width of vertical radiation patterns is 39゜-50゜ throughout the band width which is 27% of it's centre frequency according to the measured data in this work.

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The triangular loop antenna loaded by a short-circuited coaxial stub is analyzed. The moment method has been used to calculate the input impedance and resonant frequency. Practical design parameters to optimize the antenna size and impedance matching are investigated.

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This contribution reports the improvement of the mobile reception measurement by TURNSTILE ANTENNA for the TV-DATA-BROADCASTING/MPX-ON-AUDIO. Reception results were improved by the ANTENNA than the rod ANTENNA.

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Recently various types of vehicular antennas which can track the satellite have been studied for mobile satellite communications. In this report, we have sumulated driving a diode into hard clipping, and got agood result. This result shows the possibilities for FDTD application to active antennas including a diode.

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A measurement method of the permittivity of the soil for the underground radar is proposed. The coaxial-dipole antenna is employed as the probe and the relative permittivity is obtained from its reflection coefficient. The structure of the antenna, the calculation method and an exampled of the measurement are introduced and are explained.

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