[LAU] Slowing down audio while keeping same pitch ?

[Shani Pribadi]

On Tue, Jul 29, 2014 at 08:47:13PM -0400, jonetsu at teksavvy.com wrote:
> Is it possible to slow down an audio file (mp3 for instance) while
> keeping the same pitch ?  Does it even make sense ?  The software would
> have to insert more of the same audio 'bits' to make it last longer.
> Is it possible ?
> 
> Cheers.
> _______________________________________________

You can use WSOLA based time-scaling (Soundtouch) [1] or Phase Vocoder
(Rubberband) [2] to do that. If you only need to play slowed down audio
mplayer/mpv has 'scaletempo' parameter (from reading the manual it seems to be
WSOLA-based). Gstreamer also has a soundtouch plugin in gst-plugins-bad.

[1] http://www.surina.net/soundtouch
[2] http://www.breakfastquay.com/rubberband