Object-Based Analysis/Synthesis Audio Coder for Very Low Bit Rates
Heiko Purnhagen, Bernd Edler, Charalampos Ferekidis · 1998
An Object-Based Analysis/Synthesis Audio Coder designed for bit rates between 4 and 16 kbit/s is presented. The coding is based on the decomposition of the input signal into audio objects which are described by appropriate source models and represented by model parameters. Object models for sinusoids, harmonic tones, and noise are utilised. 1 Introduction In the context of evolving multimedia applications new demands for very low bit rate audio coding arise. Besides high coding efficiency required to cope with the limited bandwidth of the internet or mobile transmission channels also new functionalities like flexible access to coded data and manipulation by the recipient are desired. These requirements are addressed by the current ISO/IEC MPEG-4 standardisation activities [1]. Currently there are two well established techniques available for coding of audio signals at bit rates below 16 kbit/s. On the one hand speech coding techniques make use of the specific properties of the speech ...