MP4 container file formats and methods of processing MP4 container files

摘要

A file that is compatible with a media player application that reads media files compliant with MP4, is created by including in the file a parent container containing child containers. The child containers include a metadata container containing metadata relating to the media presentation and a media data container containing media samples for multiple tracks of the media presentation. The metadata container contains multiple child containers containing metadata for the multiple tracks respectively. The metadata container contains at least one additional child container that reserves free space in the metadata container but does not contain metadata, whereby in the event of adding a track to the presentation the free space in the additional child container may be overwritten with metadata for the added track without affecting the size of the metadata container.