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MPEG transport stream (MPEG-TS, MTS or TS) is a standard container format for transmission and storage of audio, video, and Program and System Information Protocol (PSIP) data.〔(【引用サイトリンク】title=MPEG-2 Transport Stream )〕 It is used in broadcast systems such as DVB, ATSC and IPTV. Transport Stream is specified in MPEG-2 Part 1, Systems (formally known as ISO/IEC standard 13818-1 or ITU-T Rec. H.222.0).〔 Transport stream specifies a container format encapsulating packetized elementary streams, with error correction and stream synchronization features for maintaining transmission integrity when the signal is degraded. Transport streams differ from the similarly named program streams in several important ways: program streams are designed for reasonably reliable media, such as discs (like DVDs), while transport streams are designed for less reliable transmission, namely terrestrial or satellite broadcast. Further, a transport stream may carry multiple programs. ==Layers of communication== A transport stream encapsulates a number of other substreams, often Packetized elementary streams (PES) which in turn wrap the main data stream of an MPEG codec, as well as any number of non-MPEG codecs (such as AC3 or DTS audio, and MJPEG or JPEG 2000 video), text and pictures for subtitles, tables identifying the streams, and even broadcaster-specific information such as an electronic program guide. Many unrelated streams are often mixed together, such as several different television channels, or multiple angles of a movie. Each stream is chopped into (at most) 188-byte sections and interleaved together; because of the tiny packet size, streams can be interleaved with less latency and greater error resilience compared to program streams and common containers such as AVI, MOV/MP4, and MKV, which generally wrap each frame into one packet. This is particularly important for videoconferencing, where even one large frame may introduce unacceptable audio delay. Transport streams tend to be broadcast as Constant bitrate (CBR) to maintain a consistent broadcast rate, filled with padding bytes when not enough data exists, although the Blu-Ray format does not require CBR. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「MPEG transport stream」の詳細全文を読む スポンサード リンク
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