Auxiliary information types

Sample auxiliary information provides per-sample metadata that is stored alongside media samples in an ISO base media file format track. The type of auxiliary information is identified by a four-character code (aux_info_type) carried in the SampleAuxiliaryInformationSizesBox ('saiz') and SampleAuxiliaryInformationOffsetBox ('saio'), as defined in ISO/IEC 14496-12.

The aux_info_type determines the format of the auxiliary data. When omitted, its value defaults to the protection scheme type (for encrypted tracks) or the sample entry type. A track may carry multiple streams of auxiliary information distinguished by different aux_info_type and aux_info_type_parameter values.

Registered auxiliary information types