Probabilistic phase vocoder and its application to interpolation of missing values in audio signals
Probabilistic phase vocoder and its application to interpolation of missing values in audio signals
复制标题
概率相位声码器及其在音频信号缺失值插值中的应用
DOI：
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发表时间：
2005
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通讯作者：
S. Godsill
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作者：
A. Cemgil;S. Godsill
我们制定的相位声码器-音频合成方法非常密切相关的逆短时傅立叶变换合成-作为一个高斯状态空间模型，并演示了仿真结果缺失值的插值。音频信号被建模为由线性动态系统生成的准正弦信号的叠加。我们的“生成”观点的优点是，它允许对问题进行完全的贝叶斯处理;例如，可以在任意样本值块丢失或模型参数未知的情况下执行分析。为了进行音频恢复，我们推导出一个期望最大化（EM）算法，推断丢失的样本和最大后验模型参数的期望。我们证明了我们的方法的有效性上一组具有挑战性的真实的音频的例子，并比较现有的方法。
We formulate the phase vocoder - an audio synthesis method very closely related to inverse short time Fourier Transform synthesis - as a Gaussian state space model and demonstrate simulation results on interpolation of missing values. The audio signal is modelled as a superposition of quasi-sinusoidal signals generated by a linear dynamical system. The advantage of our “generative” perspective is that it allows a full Bayesian treatment of the problem; e.g. one can perform the analysis while arbitrary chunks of sample values are missing or model parameters are unknown. To perform audio restoration, we derive an expectation-maximisation (EM) algorithm that infers the expectations of missing samples and maximum a-posteriori model parameters. We demonstrate the validity of our approach on a set of challenging real audio examples and compare to existing methods.