SoundTouch is an open-source audio processing library for changing the Tempo, Pitch and Playback Rates of audio streams or audio files. The library additionally supports estimating stable beats-per-minute rates for audio tracks.

• Tempo (time stretch): Changes the sound to play at faster or slower tempo than originally without affecting the sound pitch.
• Pitch (key) : Changes the sound pitch or key while keeping the original tempo (speed).
• Playback Rate : Changes both tempo and pitch together as if a vinyl disc was played at different RPM rate.

The SoundTouch library is intended for application developers writing sound processing tools that require tempo/pitch control functionality, or just for playing around with the sound effects.

The SoundTouch library source kit includes also an example utility SoundStretch for processing .wav audio files from command-line interface.

Access the source codes in gitlab or download the compiled executables.

www.surina.net/soundtouch
gitlab.com/soundtouch