AERO: Audio Super Resolution in the Spectral Domain
This work addresses audio quality enhancement for applications in speech and music processing, representing an incremental improvement with a novel method for handling phase information.
The paper tackles audio super-resolution for speech and music by proposing AERO, a model that processes complex-valued spectrograms in the spectral domain, and it outperforms baselines on metrics like Log-Spectral Distance, ViSQOL, and MUSHRA tests.
We present AERO, a audio super-resolution model that processes speech and music signals in the spectral domain. AERO is based on an encoder-decoder architecture with U-Net like skip connections. We optimize the model using both time and frequency domain loss functions. Specifically, we consider a set of reconstruction losses together with perceptual ones in the form of adversarial and feature discriminator loss functions. To better handle phase information the proposed method operates over the complex-valued spectrogram using two separate channels. Unlike prior work which mainly considers low and high frequency concatenation for audio super-resolution, the proposed method directly predicts the full frequency range. We demonstrate high performance across a wide range of sample rates considering both speech and music. AERO outperforms the evaluated baselines considering Log-Spectral Distance, ViSQOL, and the subjective MUSHRA test. Audio samples and code are available at https://pages.cs.huji.ac.il/adiyoss-lab/aero