Video and audio compression
ISDB has adopted the MPEG video and audio compression system. ATSC and DVB also adopted the same system. DVB and ISDB also provide for other video compression methods to be used, including JPEG and MPEG, although JPEG is only a required part of the MHEG standard. In fact Brazil is using ISDB for terrestrial broadcasting ISDBT, being that video is being encoded with MPEG AVC H. and audio with HEAAC .MPEG is widely used as the format of digital television signals that are broadcast by terrestrial overtheair, cable, and direct broadcast satellite TV systems. It also specifies the format of movies and other programs that are distributed on DVD and similar discs. As such, TV stations, TV receivers, DVD players, and other equipment are often designed to this standard. MPEG was the second of several standards developed by the Moving Pictures Expert Group MPEG and is an international standard ISOIEC . Parts and of MPEG were developed in a joint collaborative team with ITUT, and they have a respective catalog number in the ITUT Recommendation Series.
While MPEG is the core of most digital television and DVD formats, it does not completely specify them. Regional institutions can adapt it to their needs by restricting and augmenting aspects of the standard. See Profiles and Levels.MPEG includes a Systems section, part , that defines two distinct, but related, container formats. One is the Transport Stream, designed to carry digital video and audio over possibly lossy media, such as broadcasting, examples of which include ATSC, DVB and SBTVD. MPEG Systems also defines Program Stream, a container format designed for reasonably reliable media such as optical discs, DVDs and SVCDs. MPEGSystem is formally known as ISOIEC and as ITUT Rec. H...The Video section, part of MPEG, is similar to the previous MPEG standard, but also provides support for interlaced video, the format used by analog broadcast TV systems. MPEG video is not optimized for low bitrates, especially less than Mbits at standard definition resolutions. However, it outperforms MPEG at Mbits and above. All standardscompliant MPEG Video decoders are fully capable of playing back MPEG Video streams. MPEGVideo is formally known as ISOIEC and as ITUT Rec. H..With some enhancements, MPEG Video and Systems are also used in some HDTV transmission systems.
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