Audio object coding based on optimal parameter frequency resolution

Abstract

Object-based audio content is becoming the main form of audio content, because it is more interactive and flexible than traditional channel-based audio content. The Spatial Audio Object Coding (SAOC) method is proposed to encode multiple audio objects at low bitrate. However, SAOC extracts only a few parameters for each frame signal, which leads to low parameter frequency resolution. So the decoded signals have serious aliasing distortion which will destroy the sound quality. In this paper, we present a novel audio object coding method. We are the first to analyze how the signal distortion varies with parameter frequency resolution, and determine the optimal resolution to reduce aliasing distortion. In addition, we also achieve low coding bitrate by the dimensional reduction algorithm. Both the objective and subjective experiments confirm that the proposed method can provide higher sound quality of output signals than the state-of-the-art methods at equivalent bitrate.