BACKWARD COMPATIBLE ENHANCEMENT OF DTS MULTI-CHANNEL AUDIO CODING THAT DELIVERS 96 KHZ/24-BIT AUDIO QUALITY

摘要

The DTS core-plus extension multi-channel audio coding methodology permits established audio codingsystems to operate at higher bit rates and/or higher sampling frequencies while remaining compatible withfirst generation decoders (legacy decoders). While popular algorithms such as DTS Coherent Acoustics,Dolby AC-3 and MPEG II can all benefit from our process, we describe in detail its specific application tothe DTS sub-band ADPCM coding algorithm. A compatible bit stream is made up of ‘core’ data,representing 48 kHz encoded audio signals, and ‘extension’ data, representing differential audio data and/orhigher frequency components. Existing core-only decoders make use of the core data to reproduce 48kHzsampledaudio. New 96kHz decoders make use of both core and extension data to reproduce 96kHz audio.We describe the efficient real-time implementations of the 5.1ch, core+extension decoder on a singleSHARC 21065L 32-bit floating-point processor and the encoder on a Pentium III processor.