Parallel online time warping for real-time audio-to-score alignment in multi-core systems

The audio-to-score framework consists of two separate stages: preprocessing and alignment. The alignment is commonly solved through offline dynamic time warping (DTW), which is a method to find the path over the distortion matrix with the minimum cost to determine the relation between the performance and the musical score times. In this work we propose a parallel online DTW solution based on a client–server architecture. The current version of the application has been implemented for multi-core architectures ($$\times $$×86, $$\times $$×64 and ARM), thus covering either powerful systems or mobile devices. An extensive experimentation has been conducted to validate the software. The experiments also show that our framework allows to achieve a good score alignment within the real-time window using parallel computing techniques.