WSOLA (Waveform Similarity Overlap-Add) wraps the source to change playback tempo without altering pitch.
It works by extracting overlapping analysis windows from the input, applying a Hann window, and overlap-adding them at a fixed spacing. With 50% overlap the Hann windows sum to unity, giving artifact-free output. The ratio of analysis hop to synthesis hop controls the tempo change.
WSOLA (Waveform Similarity Overlap-Add) wraps the source to change playback tempo without altering pitch.
It works by extracting overlapping analysis windows from the input, applying a Hann window, and overlap-adding them at a fixed spacing. With 50% overlap the Hann windows sum to unity, giving artifact-free output. The ratio of analysis hop to synthesis hop controls the tempo change.