This document provides a tutorial on the MPD and IMSC1 timelines, as well as recommendations on an initial “launch” constraint set. The purpose of the recommendations in this document is to provide interoperability of the ATSC 3.0 IMSC1 Component. Broadcasters and others have noticed inconsistencies with early IMSC1 encoding and decoding implementations. This is a proposed solution to this issue. The goal is to provide conformant and consistent encoding and decoding, including a conformance test plan. The target audience is engineers. It is assumed that the reader is knowledgeable about MPEG DASH, ISO BMFF, and IMSC1 in general.
Download T/300, “ATSC Technology Group Report – ATSC 3.0 Launch – DASH Timeline and IMSC1”, approved 9 October 2020.
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ATSC, the Broadcast Standards Association, is an international, non-profit organization developing voluntary standards and recommended practices for digital terrestrial broadcasting. Serving as an essential force in the broadcasting industry, ATSC guides the seamless integration of broadcast and telecom standards to drive the industry forward. Currently, the ATSC 3.0 Standard is providing the best possible solution for expanding the potential of the broadcast spectrum beyond its traditional application to meet changing needs. From conventional television to innovative digital data services, ATSC has one clear goal: to empower the broadcasting ecosystem like never before.
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