Integration of Acoustic Coherence Index (ICA) for Phase-Reliable Media Coding

This contribution proposes a normative extension to the IEEE 1857.2 audio coding standard through the introduction of the Acoustic Coherence Index (ICA), a novel metric that quantifies phase structural stability in the time-frequency domain. By integrating ICA as a probability state estimator within the Context-Adaptive Binary Arithmetic Coding (CABAC) entropy engine, encoders can selectively allocate bits to preserve biologically relevant phase coherence while efficiently quantizing incoherent spectral components.Preliminary evaluations demonstrate compression efficiency gains of 9-15% bitrate reduction at equivalent perceptual quality (PEAQ ODG), with statistically significant improvements in listening effort metrics as measured by pupillometry and EEG. The proposed framework also provides an emergent capability for distinguishing synthetic from biological acoustic sources, though this secondary benefit requires further validation as synthesis technologies evolve. We request the P1857.16 Working Group to establish an ad hoc evaluation task force, integrate the ICA reference implementation into the conformance test suite, and consider the proposed CABAC context modification for inclusion in the next amendment cycle.