ISO/IEC 14496-12:2020

INTERNATIONAL ISO/IEC
STANDARD 14496-12
Sixth edition
2020-12
Information technology — Coding of
audio-visual objects —
Part 12:
ISO base media file format
Technologies de l'information — Codage des objets audiovisuels —
Partie 12: Format ISO de base pour les fichiers médias
Reference number
©
ISO/IEC 2020
© ISO/IEC 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
ii © ISO/IEC 2020 – All rights reserved

Contents Page
Foreword .ix
Introduction .x
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 2
3.1 Terms and definitions . 2
3.2 Abbreviated terms . 6
4 Object-structured file organization . 6
4.1 File structure . 6
4.2 Object structure. 6
4.2.1 Object syntax conventions . 6
4.2.2 Object definitions . 7
4.3 File-type box . 9
4.3.1 Definition . 9
4.3.2 Syntax . 9
4.3.3 Semantics . 9
4.4 Extended type box .10
4.4.1 Definition .10
4.4.2 Syntax .10
4.4.3 Semantics .10
5 Design considerations .10
5.1 Usage.10
5.1.1 Multi-purpose .10
5.1.2 Interchange .11
5.1.3 Content creation .11
5.1.4 Preparation for streaming .11
5.1.5 Local presentation .12
5.1.6 Streamed presentation .12
5.2 Design principles .12
6 ISO base media file organization .13
6.1 Presentation structure .13
6.1.1 Referencing external data .13
6.1.2 Object structure .13
6.1.3 Meta data and media data .13
6.1.4 Track identifiers .13
6.2 Metadata structure (objects) .14
6.2.1 Box . .14
6.2.2 Data types and fields .14
6.2.3 Box order .15
6.2.4 URIs as type indicators .18
6.3 Brand identification .19
6.4 Time structure overview .19
7 Streaming support .19
7.1 Handling of streaming protocols .19
7.2 Protocol ‘hint’ tracks .20
7.3 Hint track format .20
8 Box structures .22
8.1 File structure and general boxes .22
8.1.1 Media data box . .22
8.1.2 Free space box .22
8.1.3 Progressive download information box .23
© ISO/IEC 2020 – All rights reserved iii

8.1.4 Identified media data box .23
8.2 Movie structure .24
8.2.1 Movie box .24
8.2.2 Movie header box .24
8.3 Track structure .25
8.3.1 Track box .25
8.3.2 Track header box .26
8.3.3 Track reference box .29
8.3.4 Track group box .30
8.3.5 Track type box .32
8.4 Track media structure .32
8.4.1 Media box .32
8.4.2 Media header box .32
8.4.3 Handler reference box .33
8.4.4 Media information box .34
8.4.5 Media information header boxes .34
8.4.6 Extended language tag .35
8.5 Sample tables .36
8.5.1 Sample table box .36
8.5.2 Sample description box .36
8.5.3 Degradation priority box .38
8.5.4 Sample
...