Pulse-code modulation: Difference between revisions

Revision as of 07:28, 31 December 2022

Revision as of 18:46, 13 January 2023

Line 30:

{{Modulation techniques}}

'''Pulse-code modulation''' ('''PCM''') is a method used to [[Digital signal (signal processing)|digitally]] represent sampled [[analog signal]]s. It is the standard form of [[digital audio]] in computers, [[compact disc]]s, [[digital telephony]] and other digital audio applications. In a PCM [[Stream (computing)|stream]], the [[amplitude]] of the analog signal is [[Sampling (signal processing)|sampled]] regularly at uniform intervals, and each sample is [[Quantization (signal processing)|quantized]] to the nearest value within a range of digital steps.

'''Linear pulse-code modulation''' ('''LPCM''') is a specific type of PCM in which the quantization levels are linearly uniform.<ref name="LOC_LPCM" /> This is in contrast to PCM encodings in which quantization levels vary as a function of amplitude (as with the [[A-law|A-law algorithm]] or the [[μ-law|μ-law algorithm]]). Though ''PCM'' is a more general term, it is often used to describe data encoded as LPCM.