3 Internet technology for future broadcast services

Transcription

1 We continued our research on how to use the internet to provide services adapted to diverse viewer environments. These days, TV programs are distributed through various media, such as broadcasting and the internet, and viewed on diverse terminals including smartphones. Toward this backdrop, we began a study on a cloud-based media-unifying platform that automatically selects appropriate media and distribution sources for displaying programs in accordance with the viewer situation, and we prototyped a system. To realize the system, we investigated a link description scheme and conducted experiments to measure the reception status of broadcasting and broadband networks in living environments. We conducted verification experiments on a system that synchronizes real-time data on broadcasting by using Hybridcast's high-accuracy synchronization function between broadcasting and telecommunications networks. For SHV multimedia broadcasting, we prototyped a receiver to verify a general data transport method standardized by ARIB for data multiplexed by MPEG Media Transport (MMT). In our research on device linkage services, we investigated new service systems that link TV with IT technology. We prototyped a system that presents appropriate information based on viewing logs and a smartphone's positioning information. We also developed 8K Time into Space, which displays a large number of videos on an 8K display and allows the viewer to select one by touching or gesture, and advanced Augmented TV that utilizes an augmented reality (AR) technology for TV. We also began a study on a TV-watching robot that provides company to people watching TV alone at home, for which we developed functions to detect the TV position and to generate utterances related to the program. In our research on the utilization of program information, we are studying more convenient broadcast broadband services that bridge TV viewing with daily activity. We designed and prototyped a base system for linking TV with diverse smartphone applications and Internet of Things (IoT)-enabled devices, and developed extended functions of common companion application for Hybridcast. For the effective utilization of broadcast data, we provided program data in Linked Data format, developed new educational and sports services using data structuring, and investigated entity linking that links person information contained in closed captions of programs with Wikipedia article headings. In our research on technologies for promoting Hybridcast, we conducted a browser performance test at the IPTV Forum to improve receiver performance and investigated HbbTV in Europe to examine mutual operation with HbbTV. In our research on internet delivery technology, we continued our work from FY 2015 by developing an MPEG-DASH player. Our player technologies were made available to the members of the IPTV Forum and have been widely used by commercial broadcasters and content providers, contributing to the creation of new delivery services. For more stable video distribution, we developed a delivery path control technology that carefully controls the delivery path of each viewer terminal in accordance with the congestion status and a transmission rate control technology that continues stable live video distribution even when the access connection increases. Regarding security technologies, we made progress in research on attribute-based encryption that can restrict information access by service providers according to their attributes while protecting viewer information stored on cloud servers. We developed an encryption scheme that reduces the processing burden of the viewing terminal and an encryption scheme that can search encrypted data without decryption. We also developed lightweight symmetric encryption to conceal information securely in IoTenabled devices and studied traitor tracing cryptography to prevent illegal copying of the receiver s decryption key. Moreover, we began a survey on the cyber security of broadcasters. 3.1 Cloud-based media-unifying platform We are researching technologies for making use of the Internet to provide more user-friendly and attractive broadcasting services. In FY 2016, we studied a platform that enables the easy viewing of content at any time without considering the differences in delivery paths and viewing terminals and developed technologies for an advanced broadcast broadband service on the basis of Hybridcast Technical Specification version 2.0. Media-unifying platform As media for delivering TV programs diversify to include broadcasting and the Internet, so do terminals that support the viewing of the programs such as smartphones and tablets. Against the backdrop of this diversification of program-viewing methods, we are researching a media-unifying platform that automatically selects appropriate media and distribution sources for displaying programs in accordance with the viewer situation. The media-unifying platform consists of servers that 24 NHK STRL ANNUAL REPORT 2016

2 by using the media-unifying platform to select an appropriate channel (broadcasting or the Internet) according to the environment (3). We outlined scenarios where the media-unifying platform is utilized for viewing content in people s daily lives, based on which we produced video content describing a family s life in the near future and screened it at the NHK STRL Open House (Figure 3). Technologies for advanced Hybridcast Figure 1. Example of operation of the media-unifying platform prototype terminal control the program distribution status of each medium and media-unifying engines that automatically select appropriate media on the terminal side. We exhibited a prototype terminal equipped with a media-unifying engine (1) at the NHK STRL Open House 2016 and demonstrated how programs are viewed through appropriate means selected according to the viewer environment such as at home or outdoors (Figure 1). To realize the media-unifying platform, we are investigating a link description scheme that can specify content regardless of the type of distribution media. Using this scheme, the viewer can share his/her friends the link information of a program as a recommendation through SNS or without paying attention to the media type, such as broadcasting or the Internet, and the friends can view the program via a medium appropriate to their viewing environment. In FY 2016, we prototyped a function to identify the same content distributed through different media based on its metadata such as the title and verified its effectiveness (2). Using this function to derive media that can view the content specified by the link enables the viewing terminal to select an appropriate medium. To assess the reception quality of broadcasting and the Internet in various viewing environments, we developed a portable device for measuring the reception status of broadcasting and communications and conducted measurements in actual living environments such as on a train, on a bus and on foot (Figure 2). The collected data showed that the service availability rate can be improved and the amount of communication data can be reduced significantly Since its launch in 2013, Hybridcast has steadily expanded its services by welcoming the participation of commercial broadcasters. In FY 2014, the IPTV Forum published Hybridcast Technical Specification version 2.0, which enabled the highaccuracy synchronization of content between broadcasting and telecommunications and video distribution using MPEG- DASH (Dynamic Adaptive Streaming over HTTP) as we had proposed. Using these capabilities, we conducted R&D to realize more attractive Hybridcast services. To demonstrate the feasibility of services using the highaccuracy synchronization function between broadcasting and telecommunications networks, we conducted verification experiments on a system that distributes data generated in real time at a site of live sports coverage via the Internet and presents it in synchronization with broadcast images. In the experiments, we used the system with J. League soccer matches recorded live on NHK BS1. The system added time information for synchronization with the measurement data (tracking data), such as player positions. The tracking data is generated and distributed in real time by a data production service provider, uploaded to the cloud server and distributed to a Venue for on-the-spot broadcast Stadium Commercial cloud service Data production service provider Tracking data Tracking system Time server Data distribution equipment Uplink 1 Gbps Data distribution server (WebSocket) Reception environment Downlink 100 Mbps Time-mapping generator Time server Broadcast Prototype Hybridcast wave receiver supporting (NHK BS1) the synchronization Figure 2. Device for measuring broadcasting and telecommunications reception status Figure 4. System structure of the data synchronization and distribution experiment Media-unifying technology Automatically selection of an appropriate viewing method from broadcasting or the Internet Internet Broadcasting Figure 3. Video content presenting cases of use of media unification Figure 5. Prototype Hybridcast application NHK STRL ANNUAL REPORT

3 prototype Hybridcast receiver that receives BS1 broadcasting (Figure 4). The results showed that the data was successfully received prior to the arrival of broadcast images and that the data and images were synchronized with high accuracy in the receiver by using the added time information (4). Using this technology, we prototyped a Hybridcast application that displays the player position and running speed in real time during the progress of a live soccer program and exhibited it at the NHK STRL Open House 2016 (Figure 5). We also studied technologies for a multi-view service that distributes images seen from different angles via the Internet simultaneously with broadcasting and allows the viewer to select the images. We proposed a control method for reproducing MPEG-DASH video in synchronization with the broadcast images and confirmed its operation by using a prototype system (5). We also proposed and verified a method for simplifying the time mapping between broadcast content and content delivered on the Internet to achieve high-accuracy synchronization (6). SHV multimedia broadcasting Regular SHV satellite broadcasting is scheduled to start in We worked on revisions of the standards related to SHV multimedia broadcasting and conducted their verification. Figure 6. Example of an application using closed caption data We developed an experimental receiver to verify the transmission of data content multiplexed by MPEG Media Transport (MMT) and verified the cache storage control of data resources transmitted by broadcast waves and event message operation. Using this receiver, we demonstrated that closed captions can be presented in more enriched ways by using an SHV multimedia broadcasting application to retrieve the ARIB- TTML format closed caption data transmitted by the MMT multiplexing scheme and by adjusting the size, color and display position of characters (Figure 6). We also verified the operation of the general data transport method specified by an ARIB standard (7) and exhibited it at the NHK STRL Open House Using this method to push the delivery of image data and binary data on broadcast waves will enable the frequent update of data used for applications. (1) H. Endo, K. Matsumura, K. Fujisawa, K. Kai: Cross-Media Platform for the Unification of Broadcast and Broadband Program-Viewing Environments, IEEE BMSB, 7A-3 (2016) (2) S. Taguchi, H. Endo, K. Matsumura, K. Kai: Content Identification Method for Media-Unifying Platform, ITE Winter Annual Convention, 11A-4 (2016) (in Japanese) (3) H. Endo, S. Taguchi, K. Matsumura, K. Fujisawa, K. Kai: Measurement of the Reception Status of Broadcasting and Broadband by Field Experiment for a Validation of Media-Unifying Platform, ITE Tech. Journal, Vol.40, No.45, BCT , pp (2016) (in Japanese) (4) Y. Hironaka, M. Onishi, K. Matsumura, M. Takechi: Evaluation Tests of Synchronized Presentation of Live Broadcast Program and Internet Content on Hybridcast, ITE Annual Convention, 13D-1 (2016) (in Japanese) (5) M. Onishi, Y. Hironaka, K. Matsumura, M. Takechi: Prototype of Synchronization Method between Broadcast and Broadband Using MPEG-DASH Player for Hybridcast, ITE Tech. Journal, Vol.40, No.14, BCT , pp (2016) (in Japanese) (6) M. Onishi, K. Matsumura, Y. Hironaka, M. Takechi: A Consideration of Method to Convert Timestamp for Synchronization between Broadcast and Broadband on Pre-recorded Program, ITE Annual Convention, 13D-2 (2016) (in Japanese) (7) S. Takeuchi, A. Baba, K. Kai, K. Fujisawa: A Study on General Data Transport Method over MMT in Multimedia Service of UHDTV Broadcasting, ITE Winter Annual Convention, 11A-3 (2016) (in Japanese 3.2 Device linkage services We are researching service systems that will offer new user experiences beyond those of conventional TV broadcasting by taking advantage of IT technologies such as the Internet and augmented reality (AR) and by linking TV with various devices such as smartphones, tablets and sensors. Technology for providing program-related information matching the user s location We researched a content-matching service that connects program viewing to new discoveries and values not only in the living room but in various scenes in daily life. We developed a prototype system that presents the user with topics and information related to the programs by utilizing the user s program-viewing logs in accordance with their location, identified by the positional information of their smartphone. We also studied cases of use of the content-matching service by considering the business requirements of commercial broadcasters. We demonstrated that these cases of use can be supported on a unified application at the NHK STRL Open House 2016 (Figure 1) (1). We thus demonstrated the feasibility of a new TV experience in which topics and information provided by TV programs can be utilized in daily activities, both indoors and outdoors, by using smartphones as a bridge Figure 1. Example of prototype content-matching services 26 NHK STRL ANNUAL REPORT 2016

4 to connect TV viewing and user behaviors on the Internet and in the real world. Interactive technology on 8K display We are researching user interfaces (UIs) using versatile web technologies for enabling interactive services on 8K displays and the 8K Time into Space image presentation technology that can reproduce a huge number of videos simultaneously on one display (2). In our work on UIs, in FY 2016, we incorporated a gesture recognition device into our prototype system in addition to a touch sensor so that users can intuitively operate web content on an 8K display. We achieved an environment that allows not only touch operation but noncontact operation of the 8K display screen from a distance. We developed a new image presentation technology taking advantage of high-definition 8K displays, called 8K Time into Space. This technology subdivides a single TV program or movie into hundreds of moving images in chronological order and plays them simultaneously on one screen so that the viewer can obtain a view of the whole sequence of the video content. Our new mechanism of showing continuous still images similarly to a moving image and our new web technology that reduces the processing load of playback made it possible to reproduce a huge amount of video content simultaneously at a rate more than 15 frames per second regardless of the length or number of partitions of the video. In addition, by using the aforementioned UI, we developed a new viewing style in which the viewer can view a program by freely going back and forth between the thumbnails of the entire program and a selected scene displayed with high definition. 8K Time into Space was selected by the Ministry of Economy, Trade and Industry as one of 20 innovative technologies in 2016 to promote innovation in digital content. We demonstrated of 8K Time into Space at Digital Content EXPO 2016 as a selected technology. This research was conducted in cooperation with Massachusetts Institute of Technology(MIT) Media Lab. Device-linked system technology using AR We are studying AR technology for broadcasting services. We conducted R&D on a device linkage system called Augmented TV that will provide a new viewing experience through mobile devices such as smartphones and tablets. This system will enable extra broadcast content to be shown in front of a TV screen by overlaying 3D CGs on TV images shown on a mobile device. In FY 2016, we developed a method for representing the continuous space between the inside and outside of a TV screen by modifying the arrangement and shape of 3D CG objects (3). The method formulates the 3D space within the TV screen by focusing on the geometric coherency of the appearance according to the viewing position. By doing so, the method can create a natural representation of an object Figure 2. 8K Time into Space Figure 3. Experiment on TV detection by TV-watching robot appearing to fly straight out of the TV screen regardless of the position of the mobile device. We also presented at a conference a technology for enabling viewers not having a mobile device to also enjoy the service, which we developed in FY 2015 jointly with the Kanagawa Institute of Technology (4). Augmented TV received the 2015 Technical Promotion Award (Content Technology Award) from the Institute of Image Information and Television Engineers. TV-watching robot As the number of single-person households increases due to Japan s aging society, along with trends toward nuclear families and diverse styles of TV viewing, an increasing number of people are watching TV alone, instead of enjoying it with other people. Against the backdrop of these changes in society, we began developing a TV-watching robot to allow viewers to share the enjoyment of watching TV with others by using a communication robot. In FY 2016, we developed a function to automatically detect the position of the TV and viewer in a living room and a function to generate utterances related to the program being viewed, and we implemented these functions into an experimental communication robot. For the automatic detection of the TV position, a camera mounted on the robot set in the living room captures the surrounding environment. The TV position is detected by extracting the feature values of the luminance difference and edges from the captured video and calculating each image moment. Experiments in a laboratory simulating a living room (Figure 3) demonstrated that this detection method achieved an accuracy of about 88%, which is higher than that of calculating each feature value separately (5). We also developed a function to detect the position of a person by applying a face detection technology using the camera built in the robot and a sound localization technology using a microphone array and incorporated it into the prototype robot. For the generation of utterances related to the program being viewed, we developed a technology to enable a robot to say what it feels about the program as people do. This technology generates an utterance text by extracting keywords that are highly related to the genre of the TV program from the program information and subtitles and combining them with template sentences that express emotions (e.g., want to go, want to see, want to eat). We incorporated this utterance generation function into the prototype robot and enabled the robot to turn to the TV or to the viewer and make utterances. (1) C. Yamamura, M. Ikeo, A. Baba, H. Fujisawa, M. Uehara: Design of information provision for connecting TV and Life Activities, Proc. of ITE Annual Convention, 13D-3 (2016) (in Japanese) NHK STRL ANNUAL REPORT

5 (2) H. Ohmata, A. Lippman: 8K Time into Space: Web-based Interactive Storyboard with Playback for Hundreds of Videos, Proceedings of 2016 IEEE International Symposium on Multimedia (ISM 2016), pp (2016) (3) H. Kawakita, M. Uehara: Visual Coherence Between 2D Moving Pictures and 3D Real Space for Augmented TV, 33rd Technical Committee Conference of Cyberworlds IEICE, pp.1-4 (2016) (in Japanese) (4) H. Kawakita, M. Uehara, T. Nakagawa, Y. Suzuki, H. Suzuki, A. Shirai: Investigation of an Application for Augmented TV with ExPixel, Proc. of ITE Annual Convention, 11C-1 (2016) (in Japanese) (5) Y. Hoshi, Y. Kaneko, Y. Kawai, M. Uehara: A Study on detection methods of TV position in living room, Proc. of ITE Winter Annual Convention, 22B-6 (2016) (in Japanese) 3.3 Program information utilization technology With the aim of making content more accessible and increasing user satisfaction in the era of convergence of broadcasting and internet services, we are studying how broadcasters and service providers can provide viewers with content that matches their lifestyle. System for connect daily activity and TV viewing In FY 2016, we began research on more convenient broadcast-broadband services that connect TV viewing and daily activities in our life by using internet. Based on the current situation of increasing the amount of time spent for smartphone, we designed a system architecture that enables TV to interact with various applications and IoT-enabled devices via smartphones and an application framework which constitute a core part of this architecture. In addition, we prototyped this framework as extended function of companion application for Hybridcast (1)(2). We verified the system with various use cases and confirmed the versatility of the framework for various services. Broadcaster Hybridcastenabled TV Broadcasting In front of a TV Broadcaster s programrelated information Data linkage Services and data of various providers Secure utilization of viewing data and content targeting of broadcaster for each user s situation TV linkage (Mobile-centric) Current Hybridcast linkage (TV-centric) IoT linkage Service provider Healthcare Outside of a home Figure 1. System model for services to connect TV viewing and daily activities Data linkage and data-structuring technologies CA Extension Viewing data Activity data Companion Screen Companion Application Program-related information Activity data Location linkage IoT linkage Various daily activities We are investigating how broadcaster data can be utilized for diverse services offered by non-broadcasters. To make the coverage of the investigation as wide as possible, we progressed the work from both data creation and its utilization aspects. For data creation aspect, we made program guide data and data related to video for the web applications NHK Video Map MICHISHIRU and NHK Chiiki Dukuri (local initiatives) Archives, available to external parties by providing them in Linked Data format. For data utilization aspect, we participated in following contest events for developers, LOD Challenge Japan 2016 and RESAS JAPAN Hackathon as a data provision partner, and Mashup Awards 2016 as an application programming interface (API) partner. We also presented NHK World data in Linked Data format to be used by the smartphone app for participants of the ISWC2016 international conference held in Kobe to verify a method for utilizing data for the international promotion of content. We began developing new services that utilize NHK content Shopping Awaking in new areas such as education and sports by using datastructuring technology. This included content systematization based on the government guidelines for schoolteaching and structuring of information on sports players. This technology was utilized in the NHK web pages for NHK for School and the Rio 2016 Olympics. Entity linking of program information As an elemental technology for linking the information in programs with entities in the real world such as objects and concepts, we are researching entity linking that identifies what is actually indicated by a keyword mentioned in closed captions of programs. In FY 2016, we focused on personrelated keywords that are of great utility value and developed an entity-linking method that links person-related keywords in closed captions with Wikipedia article headings (3). The method, which is based on the analysis of the relationship among various keywords appearing in Wikipedia content, can disambiguate keywords by analyzing the link information among person keywords. The experimental application of this method to closed caption data of programs demonstrated that this method is more effective than conventional ones. Promotion of Hybridcast In addition to technological development for services and platform of Hybridcast, we are also studying technologies for promoting Hybridcast services. We conducted a performance test event with IPTV Forum Japan. Purpose of this event is to share the knowledge on the performance of Hybridcast browsers that run on TV receivers (4). Through this event, the current situation and issues of receiver performance were successfully shared between broadcasters and receiver manufacturers and recognized as a good opportunity to help improve services and receiver performance. To promote Hybridcast services globally, we began studying ways of enabling the cross-execution of applications on both Hybridcast and HbbTV that is developed and deployed mainly in Europe. We studied a basic architecture and application creation methods for ensuring the compatibility of applications between Hybridcast and HbbTV, and verified them by prototype implementation. We also conducted a survey in Europe on the current situation of actual HbbTV services and reported our findings at the IPTV Forum Japan and other parties/ organizations. (1) M. Ikeo, H. Ohmata, H. Ogawa, C. Yamamura, M. Miyazaki, H. Fujisawa: An application Framework for collaboration with TV, Internet and Real World, Proc. of 79th National Convention of IPSJ (2017) (in Japanese) (2) H. Ogawa, M. Ikeo, H. Ohmata, H. Fujisawa: IoT Device Connection Architecture for Broadcast Content, Proc. of 79th National Convention of IPSJ (2017) (in Japanese) (3) M.Urakawa, H.Fujisawa: Data Interchange between Sports Event and Program Information based on Ontology, Proc of ITE Winter Annual Convention, 25C-3(2016) (in Japanese) 28 NHK STRL ANNUAL REPORT 2016

6 (4) M. Naemura, M. Miyazaki, M. Urakawa, H. Fujisawa: Entity Linking of Person Keywords using Group Tree Structured Graph, IEICE Technical Report, Vol.116, No.213, NLC , pp (2016) (5) M. Ikeo, K. Matsumura, H. Fujisawa, M. Takechi: A Study of HTML5 Web Browser Performance on Hybridcast TV Receiver, Proc. of ITE Winter Annual Convention, 15B-3 (2016) (in Japanesse) 3.4 Internet delivery technology For large-scale and stable video distribution over the Internet, we are researching video player technologies, delivery path control in accordance with reception status and transmission rate control for video distribution. Video player technologies We made progress in our development of an MPEG-DASH (Dynamic Adaptive Streaming over HTTP) video player that can playback MPEG-DASH Internet video stably on HTML5 browsers of various viewing terminals such as Hybridcastenabled TVs, PCs and smartphones (Figure 1). In FY 2015, we made our MPEG-DASH player available to the MPEG-DASH interoperability study group at the IPTV Forum to help realize a stable video delivery service using MPEG-DASH. Our player, named dashnx, is available to members of the study group. In FY 2016, we equipped our player with extended functions for satisfying broadcasters service requirements, such as inserting another video into a program seamlessly, and with application programming interfaces (APIs) to customize viewing operation using these functions. Moreover, we provided a sample player under development equipped with basic operations of video playback and API samples as well as a test website for operation verification so that the member companies can immediately embark on service development. As a result of these efforts, our player has been widely used by commercial broadcasters and distribution service providers, contributing to demonstration experiments on Hybridcastbased 4K video delivery and the creation of new video delivery services such as a 4K video delivery service. In recognition of these achievements, we were awarded the METI Minister s Award (MPTE Award) by Motion Picture and Television Engineering Society of Japan, Inc. (1) Delivery path control in accordance with reception status For low-cost and stable video delivery, we made progress in our development of a method for carefully controlling the delivery path to each terminal using diverse delivery paths including multiple content delivery networks (CDNs) and distribution equipment built on cloud servers. In this method, the distribution side decides the best delivery path to each viewing terminal by collecting the reception-status information Figure 1. Playback video on various terminals using MPEG-DASH player such as the network throughput measured by each terminal and determining the congestion status of each delivery path. In response to instructions from the distribution side, each terminal changes the delivery path. We built a prototype system by incorporating a function to measure and notify reception status and a function to change the delivery path into the MPEG-DASH player that we developed in FY We operated this prototype system on a cloud server and verified the operation of delivery path control using multiple distribution servers. The results showed that the degradation in viewing quality could be suppressed by changing the delivery path to a different distribution server with sufficient capacity in the case of congestion on one distribution server (2). We also exhibited the actual operation at the NHK STRL Open House 2016 (Figure 2). Without delivery path control (Conventional method) Temporal transition of measured network throughput (Different colors for each distribution server) Temporal transition of the quality of received video With delivery path control (New method) Figure 2. Comparison of viewing quality between systems with/without delivery path control Transmission rate control for video distribution We developed a method for carefully controlling video transmission rates in accordance with the congestion status of distribution servers as a way of ensuring the stable quality of live video distribution even if the number of accessing terminals increases. The method constantly monitors the number of viewing terminals connecting to distribution servers and controls transmission rates in real time to ensure that the total of the video transmission rates to all the connected terminals is less than the transmission capacity of distribution servers. We built a prototype distribution system equipped with this method in a cloud server environment and verified its operation. The results showed that this method can suppress fluctuation in video quality and provide video with a stable quality compared with conventional methods, even when an increase in the number of viewing terminals causes congestion in distribution servers (3). We also exhibited the actual operation at the NHK STRL Open House (1) S. Nishimura: Development of a Hybridcast compatible MPEG-DASH player, The Motion Picture and Television Engineering, No.771, pp (2016) (in Japanese) (2) S. Tanaka, S. Nishimura, M. Yamamoto: Adaptive Delivery Path NHK STRL ANNUAL REPORT

7 Control Method Based on Each Terminal's Reception-Status in Video Distribution, IEICE Society Conference, B-6-16, 2016, p.16 (2016) (in Japanese) (3) M. Kurozumi, S. Oda, S. Nishimura, M. Yamamoto: Video Distribution Technology by a Transmission Rate Control According to a Congestion Situation of Distribution Servers, ITE Annual Report, 11D-1 (2016) (in Japanese) 3.5 Security technologies To ensure the security and reliability of programming in the era of the convergence of broadcasting and telecommunications, we researched cryptography and security technologies that can be used to provide secure services. Cryptography algorithm for cloud services Service providers need information about viewers in order to personalize services. Also, to allow viewers to receive unknown and unexpected services, many service providers need to have this information. An efficient way to meet this requirement is to store viewer information in the cloud server and allow various providers to access the information, but it is necessary to restrict access to the information to preserve viewers privacy. To meet these conflicting conditions, we researched attribute-based encryption scheme that can specify the access rights of providers to information according to their attributes. To reduce the burden of the encryption process on the viewer terminal, we developed an encryption scheme that divides up the process so that part of it can be handled by cloud servers (1)(2)(3). We also developed an encryption scheme that can search encrypted data without decryption in order to reduce the data that providers can access to the minimum necessary (4). In addition, we developed an access control system that enables viewers to view paid broadcasting services even from outside the home when the attribute-based encryption scheme that we developed in FY 2015 is used for paid broadcasting services (5). Lightweight encryption algorithm We researched symmetric encryption that would enable safe and secure information transmission in an environment where diverse Internet of Things (IoT)-enabled devices are connected to the Internet. We developed a lightweight symmetric encryption scheme so that even data from devices with a lowperformance CPU can be concealed securely. Traitor tracing encryption scheme We researched a traitor tracing encryption scheme to identify an illegally copied decryption key as a countermeasure against illegal copying of receiver decryption keys. To identify which decryption key has been used, each receiver needs to have a unique decryption key, and a pirate receiver created using the copied decryption key needs to be tested in order to determine the key. If the pirate receiver detects this test, however, it can interrupt the test by stopping operation. To prevent this from happening, we devised a content delivery method that makes a test indistinguishable from an actual service (6). Survey on cyber security of broadcasting systems We began a survey on the cyber security of broadcasting systems. We investigated actual cyber-attack technologies and analyzed the risk of cyber-attacks against broadcasting systems. We also surveyed cyber security trends in the domestic and international broadcasters. (1) N. Attrapadung, G. Hanaoka, K. Ogawa, G. Ohtake, H. Watanabe, S. Yamada: Attribute-Based Encryption for Range Attributes, SCN2016, pp (2016) (2) G. Ohtake, R. Safavi-Naini, L. Zhang: Implementation and Evaluation of Outsourcing Scheme of Attribute-Based Encryption, IEICE ISEC Technical Report, Vol.116, No.129, ISEC , pp (2016) (in Japanese) (3) G. Ohtake, R. Safavi-Naini, L. Zhang: Outsourcing Scheme of ABE Encryption Secure against Malicious Adversary, ICISSP2017, pp (2017) (4) G. Ohtake, R. Safavi-Naini, L. Zhang: Efficient Verifiable Attribute- Based Keyword Search, IEICE ISEC Technical Report, Vol.116, No.505, ISEC , pp (2017) (in Japanese) (5) K. Ogawa, S. Tamura, G. Hanaoka: Functional Encryption to Enrich Broadcasting Services, Symposium on Cryptography and Information Security (SCIS) 2017, 4F2-3 (2017) (6) K. Ogawa, G. Hanaoka, H. Imai: How to Make Traitor Tracing Schemes Secure against a Content Comparison Attack in Actual Services, IEICE Trans. Fundamentals, Vol.E100-A, No.1, pp (2017) 30 NHK STRL ANNUAL REPORT 2016