《aes17-44-mp4v2》.pdf

Hannover An Overview of MPEG-4 Audio Version 2 Heiko Purnhagen Laboratorium für Informationstechnologie University of Hannover, Germany Hannover Outline Introduction Review of MPEG-4 Audio Version 1 New Tools of MPEG-4 Audio Version 2 Outlook Conclusions 2 Hannover Introduction: MPEG-4 New multimedia applications demand ... – efficient flexible coding of natural synthetic audiovisual content = Development of MPEG-4 Standard: Coding of audiovisual objects MPEG-4 Audio Version 1 (Oct. 1998) – audio and speech coding @ 2 .. 64+ kbit/s/ch MPEG-4 Audio Version 2 (Dec. 1999) – additional functionalities 3 Hannover Introduction: MPEG-4 Versions Problem: Tight schedule for MPEG-4 = several promising tools not mature in time Solution: MPEG-4 Version 2 (Amendment 1) – backward compatible extension of Version 1 – new tools added = additional functionalities MPEG-4 Version 2 Version 1 4 Hannover Version 1: Overview Analysis Coding Audio Bit Signal Stream Source Perception Model Model MPEG-4 Audio Requirements: – efficient coding (various content types / bit rates) – other functionalities