Variable Subband Analysis for High Quality Spatial Audio Object Coding

Spatial Audio Object Coding (SAOC) handles a number of audio objects to provide a user with active audio services. It represents all objects as a stereo downmixed signal with some side information, and the bitrate can be significantly reduced compared to that of the conventional audio coders. In spite of the advantage of bitrate reduction, the SAOC has the severe problem such as the degradation of sound quality. To solve the problem while minimizing increase of the bitrate, variable subband analysis and the revised SAOC structure called two-step structure were proposed in this paper. Through a subjective listening test, it was confirmed that the proposed method improves sound quality by a small bitrate increase.