sonic - Speech speed manipulator sonic [OPTION]... inFile outFile Sonic is used to make wav files of speech faster or slower. The primary advance in sonic is the ability to speed speech up by much more than 2X, with minimal distortion. However, sonic can be used for both speeding up and slowing down speech files. Additionally, sonic can change the pitch and volume.

-c Modify pitch by emulating vocal chords vibrating faster or slower. This causes more distortion than the default pitch scaling, but sounds more like the same person trying to talk higher or lower. The default pitch changes makes the voice sound like a larger or smaller person, but introduces little distortion.

-p pitch Set pitch scaling factor. 1.3 means 30%% higher.

-q Disable all speed-up heuristics, possibly improving the quality slightly. This is mainly used for debugging the speed-up heuristics.

-r rate Adjust the speed of playback. This scales both the pitch and speed equally.

-s speed Set speed up factor. 1.0 means no change, 2.0 means 2X faster.

-v scaleFactor Scale volume by scaleFactor. 1.5 increases by 50%. Clips if the maximum range is exceeded.

sonic -s 3.2 book.wav book_fast.wav The above command would increase the speed of an audio book called book.wav by a factor of 3.2, and write the result in book_fast.wav. sonic -s 0.5 -v 1.5 spanish.wav spanish_slow.wav This would slow down the file spanish.wav by a factor of 2, make the volume 50% louder, and write the result to spanish_slow.wav. sonic -p 2.0 low.wav high.wav This would make a low voice sound very high pitched. Bill Cox waywardgeek@gmail.com Sonic Version 0.2, Copyright 2010, Bill Cox, Apache 2.0 license