IVAS codec
Immersive Voice and Audio Services (IVAS) is the new 3GPP voice communication codec, co-created by 13 companies—with Nokia as a key contributor. IVAS enables live spatial audio transmission across devices such as smartphones and other connected hardware over 5G networks.
How it works
IVAS extends the widely deployed EVS (Enhanced Voice Services) mono codec into immersive services. With strong industry-wide support, we’re working together to bring spatial audio to mobile networks and services worldwide.
IVAS encodes and decodes audio streams while preserving both sound quality and spatial information. Its flexibility allows a wide range of input formats, ensuring compatibility with both legacy devices and advanced mobile systems that support spatial audio capture and playback.
Audio is compressed using advanced coding algorithms while preserving spatial metadata. Bitrate scaling enables IVAS to adapt seamlessly between low-bandwidth and high-quality scenarios.
IVAS works within IMS-based mobile networks (VoLTE, VoNR) and supports real-time transport of both audio signals and metadata (e.g., spatial position, orientation, or head-tracking).
On the receiving side, IVAS reconstructs the sound field for immersive playback. Depending on the device, audio can be rendered over headphones, built-in stereo speakers, or multi-speaker setups.
Core features
Input
Mono, stereo, multi-channel, object-based audio, scene-based audio (SBA, Ambisonics), metadata-assisted spatial audio (MASA) + combined formats of objects with SBA or MASA.
Bitrates
13.2—512 kbps
Algorithmic delay
32—38 ms
Output
To mono, stereo, multi-channel, SBA, MASA, binaural (with and without room effect, with and without head-tracking), split rendering to binaural.
Additional transport functionalities
Discontinuous Transmission (DTX)
During inactive signal portions, a Silence Insertion Description (SID) is transmitted at intervals, with Comfort Noise Generation (CNG) performed at the decoder. This results in more efficient use of network resources.
Error concealment
Protects against transmission errors and packet loss by enabling bitrate switching at any frame boundary, adapting dynamically to changing network conditions.
Jitter Buffer Management (JBM)
Compensates for packet interarrival jitter by adjusting playout delay and generating time-scale-modified versions of the spatial signal.
Real-time Transport Protocol (RTP)
Support – Includes payload formatting and SDP parameters for VoIP operation, with full backward interoperability with EVS.