Audio Processing Tools

• ​SRC - Secret Rabbit Code aka libsamplerate - downsampling software
• ​SoX - Sound Exchange

Audio Segmenting Tools

• ​FestVox Interslice

We call this project as Interslice  - to be released under Festvox (Alan 
would have more comments).

The basic idea of interslice is to automatically build synthetic voices 
from large speech databases typically available from public domain such 
as librivox.org and loudlit.org.

Interslice comes with a segmentation tool capable to handling infinitely 
large corpora and chunking them into utterances and *.lab files.

You may also want to refer to Kishore Prahallad, Arthur R Toth and Alan 
W Black,, /"Automatic Building of Synthetic Voices from Large 
Multi-Paragraph Speech Databases " 
<http://speech.iiit.net/%7Espeech/publications/interslice_v3.pdf>/, in 
Proceedings of Interspeech, Antwerp, Belgium 2007.  
http://speech.iiit.net/%7Espeech/publications/interslice_v3.pdf

Cross Platform Audio API

• ​PortAudio- portable cross-platform Audio API
  • ​Sphinx 3 sample code using portaudio
  • ​Audio::PortAudio Perl Module - an object oriented interface to the ​PortAudio library

converting to and from different audio formats

(from this ​site) Shell commands to convert audio from one format to other using ​Sox, ​LAME, ​FLAC, and ​madplay:

• flac->wav
  • flac -sd $in -o $out

• flac->mp3
  • flac -sdc $in | lame - $out

• wav->flac
  • flac -s $in -o $out

• wav->mp3
  • lame $in $out

• mp3->flac
  • madplay -q -o wave:- $in | flac -s - -o $out

• mp3->wav
  • sox $in $out