Overview: Speech audio codecs
Speech codecs organize audio coding around the characteristics and delivery requirements of spoken sound.
Speech-focused coding can use models and rate choices different from a general music codec. The introductory page establishes that purpose, followed by AMR-NB, AMR-WB and Speex as concrete formats. Their distinctions include the represented signal and the decoding support needed to reproduce it.
Speech coding
Speech coding reduces audio data by using models and signal features suited to human voices.AMR-NB
AMR-NB is the narrowband Adaptive Multi-Rate speech codec used in mobile voice and recorded speech.AMR-WB
AMR-WB is a wideband Adaptive Multi-Rate speech codec using 16 kHz sampling to carry a broader voice spectrum than AMR-NB.Speex
Speex is an open speech codec using code-excited linear prediction with narrowband, wideband, and ultra-wideband modes.