Question: When transporting encrypted Audio/Video Units (AUs) over RTP in a Transparent end-to-end Packet-switched Streaming Service (PSS), what determines the encapsulation method for non-MPEG-4 codecs with a defined mapping to the ISO Media File Format?
Option 1: The encapsulation method is determined by a specific standard reference for non-MPEG-4 codecs with an ISO Media File Format mapping.
Option 2: A custom, vendor-specific encapsulation method must be implemented for each non-MPEG-4 codec.
Option 3: The signalling in the SDP (Session Description Protocol) dictates a unique encapsulation method for each media type.
Option 4: All encrypted media, regardless of codec, must use a standardized defined encapsulation.
Explanation: For non-MPEG-4 encrypted media with a defined mapping to the ISO Media File Format, a specific standard reference determines the encapsulation method, ensuring consistency and interoperability across different codecs for seamless decryption and playback.