Efficient Primary-Ambient Decomposition Algorithm for Audio Upmix

Abstract

Decomposition of a stereo signal into the primary and ambient components is a key step to the stereo upmix and it is often based on the principal component analysis (PCA). However, major shortcoming of the PCA-based method is that accuracy of the decomposed components is dependent on both the primary-to-ambient power ratio (PAR) and the panning angle. Previously, a modified PCA was suggested to solve the PAR-dependent problem. However, its performance is still dependent on the panning angle of the primary signal. In this paper, we proposed a new PCA-based primary-ambient decomposition algorithm whose performance is not affected by the PAR as well as the panning angle. The proposed algorithm finds scale factors based on a criterion that is set to preserve the powers of the mixed components, so that the original primary and ambient powers are correctly retrieved. Simulation results are presented to show the effectiveness of the proposed algorithm.

Time-shifted principal component analysis based cue extraction for stereo audio signals

“…Simulation results and informal subjective listening tests verified the improved performance of SPCA over PCA for cue extraction in practical cases. Although several other methods have also been utilized to improve the extraction [12], [17], [19]- [22], the proposed shifted PCA based cue extraction in this paper is simple and effective.…”

“…Principal component analysis (PCA) remains one of the most widely studied methods applied in ambient-cue extraction [1], [15]- [17]. A stereo signal is generally modeled as a directional sound source mixed with uncorrelated ambience in these works.…”

Stereo upmix-based binaural auralization for mobile devices

“…From a psychoacoustic point of view, the most important spatial cues are binaural cues. However, in a stereo loudspeaker reproduction, these binaural cues are embedded in the form of inter-channel relationships, such as amplitude panning [7]- [8], [10]- [15]. Thus, a stereo-to-binaural conversion is essentially a process of transforming the interchannel relationships of a stereo signal into interaural relationships of binaural signal.…”

“…In the spatial analysis stage, the characteristics of a recording space are identified by estimating the spatial and acoustic parameters from the stereo audio. To this end, primary-ambient decomposition (PAD) has been generally performed [7]- [8], [10]- [15]. During the spatial synthesis, the estimated spatial parameters of the recording space are virtually transformed to a target format.…”

Robust Primary-ambient Signal Decomposition Method using Principal Component Analysis with Phase Alignment

“…수식 (9) 에서도 추정한 주변 성분은 패닝 계수의 값에 영향을 받는 다. 즉, 주성분의 패닝 각도가 어느 한쪽 방향으로 극단적으 로 치우쳐 있을 경우 정확하게 주변성분을 분리하지 못하 는 단점도 가지고 있다 [7] .…”