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Park H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Mitsumine H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Fujii M.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories
IEICE Transactions on Information and Systems | Year: 2011

Speeded up robust features (SURF) can detect scale- and rotation-invariant features at high speed by relying on integral images for image convolutions. However, since the number of image convolutions greatly increases in proportion to the image size, another method for reducing the time for detecting features is required. In this letter, we propose a method, called ordinal convolution, of reducing the number of image convolutions for fast feature detection in SURF and compare it with a previous method based on sparse sampling. © 2011 The Institute of Electronics, Information and Communication Engineers.


Ariyasu K.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Kawakita H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Handa T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Kaneko H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories
2014 IEEE 3rd Global Conference on Consumer Electronics, GCCE 2014 | Year: 2014

The synchronized presentation of tactile information along with audio and visual content can enhance viewing experience. In this paper, we propose two requirements of a Smart TV service: feasibility and flexibility. We then develop a tactile sensibility presentation service for a Smart TV that can synchronize tactile information transmitted through the Internet with a TV program broadcast digitally. An experiment of our proposed system shows that it realistically enhances viewing experience. © 2014 IEEE.


Shitomi T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Murayama K.,NHK Science and Technical Research Laboratories | Taguchi M.,NHK Science and Technical Research Laboratories | Asakura S.,NHK Science and Technical Research Laboratories | Shibuya K.,NHK Science and Technical Research Laboratories
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB | Year: 2012

We have developed a transmission system using ultra-multilevel orthogonal frequency division multiplexing (OFDM) technology, dual-polarized multiple-input multiple-output (MIMO) technology, and Low-Density Parity-Check (LDPC) Codes for experimental purposes on the basis of the conventional digital terrestrial broadcasting transmission scheme, ISDB-T. We conducted two field experiments: one at 23 reception points around NHK Science & Technology Research Laboratories (STRL) using an experimental transmitter installed at NHK STRL, and the other on the lawn at NHK STRL using circularly or skew polarized waves in addition to a conventional polarization set, horizontal and vertical. As a result, we obtained the required field strength in an urban environment when using the 4096QAM carrier modulation scheme with a LDPC code. Furthermore, we confirmed the advantage of circularly or skew polarized waves in an environment in which the received power differed between the horizontally and vertically polarized waves. © 2012 IEEE.


Aoki S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Aoki K.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Yamamoto M.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting 2010, BMSB 2010 - Final Programme | Year: 2010

We propose a new efficient file-transport mechanism, which is required for constructing a hybrid content delivery system incorporating broadcasting and telecommunication. Such a system combines different types of delivery channels to make effective content delivery possible. In the system, files of coded audio/video and metadata are transferred as IP packets over broadcasting channels as well as telecommunication networks. A file is segmented into data units, and file attribute information is generated for transferring. IP packets carrying these units and this information are directly multiplexed over broadcasting channels with their header compressed. We conducted experiments to verify our file-transport mechanism with a broadcasting modulator and demodulator. The results of the experiments show that files can be delivered with quite small overhead over broadcasting channels. Consequently, effective content delivery is achieved by adding the file-transport mechanism over broadcasting channels to already launched on-demand services on telecommunication networks.


Shitomi T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Asakura S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Saito S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Saito T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Shibuya K.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB | Year: 2014

We have been conducting research on a transmission system using ultra-multilevel orthogonal frequency division multiplexing (OFDM) technology and dual-polarized multiple-input multiple-output (MIMO) technology for the next generation of terrestrial broadcasting. Regarding the carrier modulation scheme, we studied a non-uniform constellation (NUC) which improves transmission characteristics by optimizing the distance between the signal points. In this study, we considered a circularly arranged NUC configured by 2m signal points in which m is an odd number. We performed simulations confirming that a NUC has advantages compared with a conventional uniform constellation (UC). Furthermore, we verified that the improvement in transmission performance varies depending on the number of signal points in the carrier modulation and the code rate of forward error correction (FEC). We also used a NUC in a dual-polarized MIMO-OFDM scheme. The results show the improvement of the NUCs tends to decrease in multipath environments. © 2014 IEEE.


Saito S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Shitomi T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Asakura S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Tsuchida K.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | And 2 more authors.
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB | Year: 2014

We are conducting research on the next generation of digital terrestrial broadcasting to enable large-volume content services such as 8K Super Hi-Vision. We have installed an experimental station for 8K transmissions in Hitoyoshi city, Kumamoto prefecture, Japan that uses dual-polarized multiple-input multiple-output (MIMO) technology and ultra-multilevel orthogonal frequency division multiplexing (OFDM) technology and conducted two 8K field experiments: a transmission test, and field measurements at 52 points in the Hitoyoshi area. In these experiments, we succeeded in carrying out the world's first terrestrial 8K transmission (91 Mbps) at a distance of over 27 km using only a single UHF (ultra-high frequency) channel (BW:6 MHz). We also measured the required field strength for the 256QAM, 1024QAM, and 4096QAM carrier modulation schemes as well as the responses of dual-polarized MIMO transmission channels. © 2014 IEEE.


Tazawa N.,NHK Engineering Services Inc. | Totihara S.,Keio Research Institute at SFC | Iwahana Y.,NHK Engineering Services Inc. | Imai A.,NHK Engineering Services Inc. | And 2 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2010

We have performed studies and evaluation experiments of more acceptable rapid speech, aimed at implementation in applications such as installation in commercial devices designed for visually impaired persons. Although our method's playback time is same as the conventional High-speed playback technology, listener might feel playing in slower speeds and listen words clearer. Our proposal technology makes it possible to adaptive speech rate control in utterance position and pitch/power in the speech information, instead of changing the speed of the utterance uniformly. We performed an experiment in Japanese and American subject with visual impairments respectively to compare the conventional high-speed playback technology and that of our adaptive high-speed playback technology in terms of "Listenability". The reaction to our proposal method from subjects with visual impairments has been very positive underscoring its potential as an effective tool for listening to high-speed speech. © 2010 Springer-Verlag Berlin Heidelberg.


Park H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Mitsumine H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Fujii M.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories
IEICE Transactions on Information and Systems | Year: 2011

This letter presents a novel edge-based blur metric that averages the ratios between the slopes and heights of edges. The metric computes the edge slopes more carefully, i.e., by averaging the edge gradients. The effectiveness of the proposed metric is confirmed by experiments with motion or Gaussian blurred real images and comparison with existing edge-based blur metrics. © 2011 The Institute of Electronics, Information and Communication Engineers.


Miyasaka H.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Narikiyo Y.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Nakamura M.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Okano M.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | And 2 more authors.
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB | Year: 2015

The next generation of digital terrestrial broadcasting systems using dual-polarized SDM-MIMO technology is under development. The reception deteriorates under an AWGN channel when the XPD for the SDM-MIMO system is low. We describe a method for inter-polarization spreading in the SDM-MIMO transmission system that compensates for the deterioration and our investigation of the reception in a computer simulation. The simulation results show that applying the spreading can improve the reception in an AWGN and in TU6 channels. They also show that the reception was even improved when using a single receiving antenna. © 2015 IEEE.


Asakura S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Shitomi T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Saito S.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Saito T.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories | Shibuya K.,NHK Japan Broadcasting Corporation Science and Technology Research Laboratories
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB | Year: 2014

NHK is conducting research on the next generation of digital terrestrial broadcasting to enable large-volume content services such as 8K Super Hi-Vision. In our previous study, we used a low-density parity-check (LDPC) block code scheme and proposed a decoding method that uses the channel response of a dual polarized MIMO transmission to further improve the bit error ratio (BER) performance [3]. LDPC block codes are robust forward error correction (FEC) codes and are Shannon-limit-approaching over an additive white Gaussian noise (AWGN) channel. Despite this feature, there is still room for improving the BER performance. In this paper, we propose spatially coupled (SC-) LDPC codes to further improve the BER performance. We also report on our verification using a computer simulation. © 2014 IEEE.

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