Organisation internationale de normalisation

Further Discusion (Thu 1600)

3D Audio Reverence Software, and Conformance streams should use FF in which

• 
  It is recommended that the first frame is IPF
  
• 
  Every frame that is IPF shall be marked using a Sync Sample table
  
• 
  Every frame that has Independency Flag set, shall be marked in a Roll Sample Group table with the positive (i.e. roll some distance ahead in time before presenting audio) frame roll distance marked.
  

Note that it is OK to have an empty Synch Sample table, which is the case if there is no IPF in the audio stream.

There was considerable discussion about audio encoder/decoder behaviour.

Experts recommended that should be a normative statement in 3D Audio specification that states the number of samples output from decoder from submitting an IPF Access Unit to the decoder and the first output audio sample associated with the IPF Access Unit.

Systems experts requested that Audio experts conduct the following experiment with the 3D Audio Reference Software decoder:

• 
  Instantiate a 3D Audio decoder and decode a bitstream structured as: IPF, 99xIF. Record the decoder output.
  
• 
  Instantiate a 3D Audio decoder and decode a bitstream structured as: 100xIF. Record the decoder output.
  

Communicate the results, as two audio signals, to Systems experts.

2.