Broadcasting Technologies for Persons with Disabilities; Current Services and Research Activities in Japan

1. Asia-Pacific Regional Forum on Mainstreaming ICT Accessibility for Persons with Disabilities Broadcasting Technologies for Persons with Disabilities; Current Services and Research Activities in Japan Tohru Takagi Senior Research Engineer, Science and Technology Research Laboratories, NHK, Japan Japan Broadcasting Corporation

2. 1. Introduction and Motivation Japan Broadcasting Corporation

3. Role of Broadcasting for Persons with Disabilities • Broadcasting is very popular media for everyone to get information, knowledge, fun and so on. • Broadcasters have a responsibility for transmitting their programs to viewers independently not only from “regional difference” but also from “individual difference”. • Solutions for persons with disabilities; • Producing TV and Radio Programs exclusively for hearing/ visually impaired person, but there are not so many • Assistive procedures for various programs; such as closed-caption, overlap of sign language and audio description

4. Approach for Persons with Disabilities in Japan • NHK started closed-captioning and audio description services in the 1980s by developing teletext and sound-multiplex broadcast of analog TV system. • Digital TV system hasstandard slots which are applicable to closed-captioning and audio description. • Ministry of Internal Affairs and Communications, Japan (MIC) has established guidelines. By the end of 2017, followings should be accomplished, (1) 100% of closed-caption including live programs (excluding technically impossible programs) (2) 10% of audio description for applicable programs

5. Approach for Aging Society in Japan • “Aging Society” is progressing rapidly in Japan. • 25% of the population will be elder than 65 by 2013, the world‘s fastest • The elderly watch TV for longer time than young people • Everyone’s “audibility” and “eyesight” gradually and certainly degrade due to aging • Especially, viewers elder than 70 often say; • Newscaster speaks too rapidly and it’s difficult to understand! • Narration or actor’s line is hard to catch because BGM or sound effect is too loud! Assistive procedure for elder’s ears is necessary

6. 2. Current Services and the Technologies Speech rate conversion radio manufactured by JVC in 2002 On-line live closed-captions Japan Broadcasting Corporation

7. (1) Closed-Captions in Japan • Production of closed-caption • Off-line closed-captions for “dramas” from 1983Manual transcription using PC based specialized machine tobe capable of adjusting the best timing, location, color etc. • On-line live closed-captions for “news” from 2000 Switching between speech recognition and special keyboards, Speedy and accurate captioning is required • How to view the closed-captions • Any digital TV set equips with a caption decoder including “One Seg” mobile device • Rate of NHK’s closed-captioned programs in 2008 • 100%(canned programs; drama, documentary, entertainment) • 49.4%(including live programs; news, sports, music show) Mobile phone with “One Seg”

8. To Increase On-Line Live Closed-Captioning Four types of captioning methods • Automatic Speech recognition developed by NHK Labs. １．Direct method • Available to Announcer and Field Reporter • Applied to News, Major League Baseball ２．Re-speak method • Another speaker listens to the program and rephrases them for speech recognition • Applied to Sports, Music programs • Keyboards with some highly skilled operators ３．Special stenographic keyboards • Applied to news etc. ４．Ordinary PC’s keyboards • Applied to Music shows MLB captions by speech recognition Re-speak method for closed-captioning

9. これまでニュースセンターに Re-speak method NHK’s Automatic Speech Recognition Method • High speech recognition performance, gender free • Switching between the program sound and the rephrased speech correspond to contents • Low operating cost with fewer correction operators • Expanding closed-captions with the system in the near future Language and acoustic models Program sound （Announcers and field reporters） Direct method Speech Text On-air Switching Error correction with only one or two operators Speech recognition Closed-captions Re-phrased speech （when original speech is noisy, spontaneous, emotional）

10. (2) Audio Description in Japan Rate of NHK’s audio description programs in 2008 4.0% (drama, informational, entertainment) MIC’s Guideline It stays at 10% of applicable programs by 2017 Reason;It takes time and labor to make audio description. Script, narration and recording are performed manually by skilled staffs. New technology is expected to assist making audio description as efficiently as possible

11. (3) Speech Rate Conversion Conventional hearing aid device It can compensate for only elder’s audible degradation related to the dynamics of loudness and frequency range. Speech Rate Conversion technology (SRC) It is effective to alleviate the difficulty of hearing rapid speech. Advantages of NHK’s SRC It maintains vocal pitch and quality. Furthermore, it can work within time slot of original program. Radio and TV receiver equipped with SRC-LSI Listeners can slow down the rate of speech in a program. Speeding up speech may be also useful for visually impaired person.

12. Ordinary Mode Adaptive Mode Slowed at first, and gradually restored It Has Two Conversion Modes Pause Good Morning everyone! Here in NHK, Original example Speech is behind its original Uniformly extended GoodMorningeveryone! Here in NHK, example Pause is shortened GoodMorningeveryone! Herein NHK, example time Converted speech is synchronized with its original speech and picture stop ■

13. Aged 60 to 69 (N=92) Aged 70 to 79 (N=137) Aged 80 or more (N=50) Evaluation ratio Adaptive mode News Sentences Number Same Original Hearing Tests by the Elderly on Adaptive Mode • Materials : 3 broadcast news sentences, about 10 seconds respectively • Evaluation : Method of paired comparison; Which do you hear slower, “original” or “Adaptive mode converted speech” ? • Result : 80% of 60s and 70s, and more than 50% of 80s+ heard “Adaptive mode” is slower than “original”.

14. Sped Up Speech by Adaptive Mode • Website service of radio news with SRC; http://www.nhk.or.jp/r-news/ (in Japanese) • Normal: original rate • Slower: “Ordinary Mode” 1.2 times of original time slot • Faster: “Adaptive Mode” 0.6 times of original time slot to be easier listening than 0.6 times by “Ordinary Mode” • Hearing test by visually impaired person • Visually impaired persons hope quick listening to get voice information. • For easy listening, 80% of subjects supported “Adaptive Mode” to speed up short sentences, to 1/2 or 1/3 times of original time slot, compared with “Ordinary Mode”. English example Same as P12 English Example stop ■ English example English example

15. 3. Research Activities for Future Services Japan Broadcasting Corporation

16. NHK Lab’s Research Activities NHK Lab’s Research Activities Web Reference Web Reference Web Reference For Visually Impaired Persons News flash readout service using speech synthesis through data broadcast Multimedia reception presentation system For Hearing Impaired Persons Sign language using computer graphics For the Elderly Objective indicator of the best balance between speech and background sound levels fitting for elder’s ear,in order to produce program sounds efficiently Web Reference

17. 4. Conclusion Further research and development are necessary to improve accessibility for persons with disabilities Higher-performance method for on-line live captioning Technical breakthrough to increase of sound description Cost and manpower are important issues to broadcasters, therefore the technologies are required to reduce them. Approach for aging society Broadcasters need suitable technologies such as to assist elder’s auditory degradation. Digital broadcast and ICT are progressing It is expected that accessibility will be enriched by collaboration of broadcasting and telecommunication.

18. Thank you for your attention NHK Science and Technology Research Laboratories Japan Broadcasting Corporation