Short for
Adaptive Differential Pulse Code Modulation, a form of
pulse code modulation (PCM) that produces a
digital signal with a lower bit rate than standard PCM. ADPCM produces a lower bit rate by recording only the difference between
samples and adjusting the coding scale dynamically to accommodate large and small differences. Some
applications use ADPCM to
digitize a voice signal so voice and
data can be transmitted simultaneously over a digital facility normally used only for one or the other.
