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1seg (Katakana: ワンセグ) is a mobile terrestrial digital audio/video and data broadcasting service in Japan. Service began experimentally during 2005 and officially on April 1, 2006. First mobile phone handsets for 1seg were sold by KDDI to consumers in autumn 2005. Image File history File links 1seg_logo. ...
Image File history File links 1seg_logo. ...
Katakana ) is a Japanese syllabary, one component of the Japanese writing system along with hiragana, kanji, and in some cases the Latin alphabet. ...
April 1 is the 91st day of the year (92nd in leap years) in the Gregorian calendar, with 274 days remaining. ...
For the Manfred Mann album, see 2006 (album). ...
KDDI Corporation is a Japanese telecommunication operator formed in October 2000 through the merger of DDI, KDD, and IDO Corp. ...
Terrestrial digital broadcast in Japan (ISDB-T) is designed so that each channel is divided into 13 segments (plus one segment for separating channels). HDTV broadcast occupies 12 segments, and the remaining (13th) one segment is used for mobile receivers. Thus the name, '1seg'. Integrated Services Digital Broadcasting (ISDB) is the digital television (DTV) and digital audio broadcasting (DAB) format. ...
High-definition television (HDTV) means broadcast of television signals with a higher resolution than traditional formats (NTSC, SECAM, PAL) allow. ...
Technical information
1seg broadcasting uses H.264 video and AAC+SBR audio encapsulated in MPEG2 Transport Stream. 1seg, like ISDB-T also uses QPSK for modulation, 2/3 FEC and 1/4 guard ratio. Total bit-rate is 416kbps. Maximum video resolution is 320x240 pixels, video bitrate is 220-320 kbit/s. Audio conforms to AAC+SBR profile, with bitrate of 48-64 kbit/s. Additional data broadcasting using BML (EPG, interactive services, etc) occupies the remaining 10-100 kbit/s. H.264 is a high compression digital video codec standard written by the ITU-T Video Coding Experts Group (VCEG) together with the ISO/IEC Moving Picture Experts Group (MPEG) as the product of a collective partnership effort known as the Joint Video Team (JVT). ...
Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. ...
FEC is an acronym which can have the following meanings: Fast Ethernet Channel (a method for bundling ethernet channels) Family Entertainment Center Farnell Electronic Components (a distributor in the United Kingdom) Federal Election Commission (administers and enforces campaign finance legislation in the United States) Florida East Coast Railway (AAR reporting...
Broadcast Markup Language, or BML, is an XML-based standard developed by Japanese ARIB association as a data broadcasting specification for digital HDTV broadcasting. ...
The Sky Digital EPG in the United Kingdom and Republic of Ireland. ...
Conditonal access and copy control is not implemented in 1seg broadcast, however each receiver device manufacturer can limit recording function. For example, W33SA receiver only allows recording 1seg broadcasts to internal memory, and disallows copy or move to external miniSD card.
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Any material not supported by sources may be challenged and removed at any time. This article has been tagged since January 2007. Almost a year after the 1seg trial started, the purpose of the service is still unclear. Mobile reception is difficult, especially in a moving vehicle/train, as the signal quality deteriorates quickly even at speeds around 20km/h (12 MPH). This leaves the majority of the target audience for this service unable to receive it. In-car reception requires use of diversity antenna and increases receiver complexity and price. In telecommunications, a diversity scheme refers to a method for improving the reliability of a message signal by utilizing two or more communication channels with different characteristics. ...
A Yagi-Uda beam antenna Short Wave Curtain Antenna (Moosbrunn, Austria) A building rooftop supporting numerous dish and sectored mobile telecommunications antennas (Doncaster, Victoria, Australia) An antenna or aerial is a transducer designed to transmit or receive radio waves which are a class of electromagnetic waves. ...
Handheld 1seg receivers generally do not work well at all in moving cars or trains, even when held by a window because the signal drops out every few seconds. There is minimal or no reception in trains that are underground, or go inside buildings, such as most of the commuter trains in Tokyo. In addition, long distance trains, especially the shinkansen, move from one service area to another in a matter of minutes, making it impossible to view a program to completion before having to scan for a new set of channels and find whatever local channel may be broadcasting the program in question. This article or section does not cite its references or sources. ...
300 (left) and 700 Series Shinkansen at Tokyo Station Shinkansen 500 Series at Kyoto Station, March 2005 The Shinkansen ) is a network of high-speed railway lines in Japan operated by Japan Railways. ...
Handheld 1seg receivers work well inside homes, although it may be necessary to be near a window and/or adjust the antenna for reception. However, a home user can watch HDTV on a large screen TV instead of a 320x180 small screen 1seg.
Even though 1seg signal is not encrypted, every receiver manufacturer chose to apply DRM, preventing users from archiving or editing 1seg contents. Digital Rights Management (generally abbreviated to DRM) is an umbrella term that refers to any of several technologies used by publishers or copyright owners to control access to and usage of digital data or hardware, and to restrictions associated with a specific instance of a digital work or device. ...
Receivers - (Japanese) NTT DoCoMo P901iTV by Panasonic
- (Japanese) KDDI/Sanyo W33SA
- (Japanese) KDDI/Sanyo W33SAⅡ
- (Japanese) KDDI/Hitachi W41H
- (Japanese) Nintendo DS (via announced add-on)
- (Japanese) Pixela PC
- (Japanese) Sanyo One-seg & car navigation system
- (English) Vodafone 905SH by SHARP
- (Japanese) Monster TV 1D PC card Type II 1Seg receiver by SKNET
- (Japanese) Sharp Papyrus PW-TC900
“NDS†redirects here. ...
The PCMCIA is the Personal Computer Memory Card International Association, an industry trade association that creates standards for notebook computer peripheral devices. ...
See also - DMB - South Korea & Europe
- DVB-H
Digital Multimedia Broadcasting (DMB) is a digital radio transmission system for sending multimedia (radio, TV, and datacasting) to mobile devices such as mobile phones. ...
DVB-H (Digital Video Broadcasting - Handheld) is a technical specification for bringing broadcast services to handheld receivers. ...
External links - (Japanese) Association for promotion of Digital Broadcasting (Japanese)
- (Japanese) 1seg promotion site (Japanese)
- (Japanese) one-seg.com (Japanese) (English)
| edit Video formats | | Analog broadcast | | 525 lines: NTSC | NTSC-J | PAL-M | | 625 lines: PAL | PAL-N | PALplus | SECAM | | Defunct systems: Pre-1940 | 405 lines | 819 lines | MUSE | MAC | | Multichannel audio: BTSC (MTS) | NICAM-728 | Zweiton (A2, IGR) | | Hidden signals: Captioning | Teletext | CGMS-A | GCR | PDC | VBI | VEIL | VITC | WSS | XDS | | Digital broadcast | | Interlaced: SDTV (480i, 576i) | HDTV (720i, 1080i) | | Progressive: LDTV (240p, 288p, 1seg) | EDTV (480p, 576p) | HDTV (720p, 1080p) | | DVB standards: MPEG-2: ATSC, DVB-T, ISDB | MPEG-4: SBTVD | | Multichannel audio: AAC (5.1) | Musicam | PCM | LPCM | | Hidden signals: Captioning | Teletext | (CPCM/Broadcast flag) | AFD | EPG | See also: Digital cinema | Ultra-high-definition video: 2540p, 4320p | 22.2 audio
| | Technical issues: 14:9 | MPEG transport | Standards conversion | Video processing | VOD | |
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