Spatial Audio Processing: MPEG Surround and Other Applications

Frequently Used Terms, Abbreviations and Notation

Terms and abbreviations

Anechoic chamber: Type of room with almost totally sound-absorbing walls, frequently used for experimentation under free-field-like conditions.

Auditory object: Perception corresponding to a single sound source. Attributes of auditory objects are location and extent.

Auditory spatial image: Illusion of perception of a space with auditory objects of specific extent and at specific locations.

BCC: Coding of stereo or multi-channel signals using a down-mix and binaural cues (or spatial parameters) to describe inter-channel relationships.

Binaural cues: Inter-channel cues between the left and right ear entrance signals (see also ITD, ILD, and IC).

BMLD: Binaural masking level difference. The difference in masked threshold due to different spatial cues of masker and target signal.

BRIR: Binaural room impulse response, modeling transduction of sound from a source to left and right ear entrances in enclosed spaces. The difference from HTRFs is that BRIRs also consider reflections.

CPC: Channel prediction coefficient.

DFT: Discrete Fourier transform.

Direct sound: Sound reaching a listener's ears or microphones through a direct (nonreflected) path.

Enclosed space: A space where sound is reflected from the walls enclosing it.

ERB: Equivalent rectangular bandwidth. Bandwidth of the auditory filters estimated from masking experiments.

Externalization: When typical stereo music signals are played back over headphones, ...