IEC Technical ISO Report ISO/IEC TR 14496-24 Information technology - Coding of Second edition 2025-08 audio-visual objects - Part 24: Audio and systems interaction Technologies de I'information - Codage d'objets audiovisuels - Partie 24: Codage audio et interaction de systemes Reference number ISO/IEC TR 14496-24:2025(en) @ ISO/IEC 2025 IS0/IEC TR 14496-24:2025(en) COPYRIGHT PROTECTED DOCUMENT @ IS0/IEC 2025 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below or ISO's member body in the country of the requester. ISO copyright office CP 40i : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Email: [email protected] Website: www.iso.org Published in Switzerland @ IS0/IEC 2025 - All rights reserved ii IS0/IEC TR 14496-24:2025(en) Contents Page Foreword. ..iv 1 Scope .1 2 Normative references .1 .2 3 Terms and definitions. 4 Motivating audio composition time stamp handling .2 .3 5 AAC Encoder/Decoder Behavior. .3 5.1 Example 1: AAC. 5.1.1 Overview ..3 5.1.2 Pre-roll 5.1.3 Edit-list. .5 5.1.4 Compressed Information and decoder behaviour 5.2 Example 2: HE-AAC .6 5.2.1 Overview ..6 .8 5.2.2 Pre-roll. Edit-list. 5.2.3 ..8 Streaming Considerations 9 6 Annex A (informative) Relevant ISO Base Media File Format Syntax 10 @ IS0/IEC 2025 - All rights reserved iii IS0/IEC TR 14496-24:2025(en) Foreword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are members of IsO or IEC participate in the development of International Standards through technical ISO and IEC technical committees collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/lEC Directives, Part 1. In particular, the different approval criteria needed for the different types of document should be noted. This document was drafted in accordance with the editorial rules of the Iso/ IEC Directives, Part 2 (see www.iso.org/directives or www.iec.ch/members experts/refdocs). ISO and IEC draw attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO and IEC take no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO and IEC had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents and https://patents.iec.ch. ISO and IEC shall not be held responsible for identifying any or all such patent rights. Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation of the voluntary nature of standards, the meaning of IsO specific terms and expressions related to conformity assessment, as well as information about Iso's adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards. This document was prepared by Joint Technical Committee ISOo/IEC JTC 1, Information technology Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information. This second edition cancels and replaces the first edition (