G.722 Wideband Audio Codec
G.722 is the standard for HD voice in SIP and enterprise telephony. When you enable 'HD Voice' on a SIP trunk, G.722 is typically what's negotiated. Essential for enterprise UC deployments.
What It Defines
G.722 is the ITU-T wideband (7 kHz audio bandwidth, 16 kHz sample rate) audio codec using sub-band ADPCM at 48, 56, or 64 kbps. Delivers noticeably higher voice quality than G.711 (PSTN bandwidth). Used in HD voice deployments and SIP trunks that support wideband.
Canonical (Normative)
The international standards body for telecommunications under the UN umbrella. Publishes Recommendations in series (E, G, H, Q, T, X…): E.164 phone numbering, G.711/G.722 audio codecs, H.323 VoIP framework, and G.9959 (Z-Wave). Free access to most Recommendations.
Related Specs
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