Opens in a new tab

AES E-Library

← Back to search

Journal Article Open Access

Elicitation of Expert Knowledge to Inform Object-Based Audio Rendering to Different Systems

Authors: Woodcock, James; Davies, William J.; Melchior, Frank; Cox, Trevor J.

Journal of the Audio Engineering Society · Volume 66 · Issue 1/2 · pp. 44–59 · January 2018

Abstract

Object-based audio (OBA) is an approach to sound storage, transmission, and reproduction whereby individual audio objects contain associated metadata information that is rendered at the client side of the broadcast chain. For example, metadata may indicate the object’s position and the level or language of a dialogue track. An experiment was conducted to investigate how content creators perceive changes in perceptual attributes when the same content is rendered to different systems and how they would change the mix if they had control of it. The main aims of this experiment were to identify a small number of the most common mix processes used by sound designers when mixing object-based content to loudspeaker systems with different numbers of channels and to understand how the perceptual attributes of OBA content changes when it is rendered to different systems. The goal is to minimize perceived changes in the context of standard Vector Base Amplitude Panning and matrix-based downmixes. Text mining and clustering of the content creators’ responses revealed 6 general mix processes: the spatial spread of individual objects, EQ and processing, reverberation, position, bass, and level. Logistic regression models show the relationships between the mix processes, perceived changes in perceptual attributes, and the rendering method/speaker layout. The relative frequency of different mix processes was found to differ among categories of audio object, suggesting that any downmix rules should be object category specific. These results give insight into how OBA can be used to improve listener experience.

Details

Publication
Journal of the Audio Engineering Society
Volume
66
Issue
1/2
Pages
44–59
Publication date
January 6, 2018
Affiliation
University of Salford, Salford, United Kingdom; BBC R&D, Dock House, MediaCityUK, Salford, United Kingdom (See document for exact affiliation information.)
Type
Journal Article