Title
A new set of directional weights for ITU-R BS.1770 loudness measurement of multichannel audio
Abstract
The ITU-R BS.1770 multichannel loudness algorithm performs a sum of channel energies with weighting coefficients
based on azimuth and elevation angles of arrival of the audio signal. In its current version, these coefficients were estimated based on binaural summation gains and not on subjective directional loudness. Also, the algorithm lacks
directional weights for wider elevation angles (|f|≥30). A listening test with broadband stimuli was conducted to collect subjective data on directional effects. The results were used to calculate a new set of directional weights. A modified version of the loudness algorithm with these estimated weights was tested against its benchmark using the collected data, and using program material rendered to reproduction systems with different loudspeaker configurations. The modified algorithm performed better than the benchmark, particularly with reproduction systems with more loudspeakers positioned out of the horizontal plane.
Keywords
Broadcasting, loudness, signal processing, spatial audio, subjective test
Authors
Leandro Pires
Agência Nacional de Telecomunicações, Brazil
Leandro Pires received the Ph.D. degree in electrical engineering from Federal University of Minas Gerais, Brazil, with a one-year placement at University of Surrey, UK. He joined Brazilian regulator for communications services Anatel in 2005, where he has been working with spectrum management and broadcast/radiocommunications licensing. His research interests include digital audio and speech signal processing. He is a member of the Brazilian Acoustical Society (SOBRAC) and the Audio Engineering Society.
Maurílio Vieira
Universidade Federal de Minas Gerais, Brazil
Maurílio Vieira holds a degree in Electrical Engineering from the Pontifical Catholic University of Minas Gerais (1987), a master's degree in Electrical Engineering from the State University of Campinas (1989) and a PhD in Electrical Engineering from the University of Edinburgh (1997). He was a professor at the Physics Department of the Universidade Federal de Minas Gerais (UFMG) from 1991 to 2012, when he moved to the Electronics Department at this university, where he is a full professor. He worked in the private sector in telephony and in the control of aluminum electrolytic reduction cells. At UFMG, he has experience in teaching and supervision of academic works in the departments of Physics, Computer Science, Linguistics, Music, Speech Therapy, and various areas of Engineering. Has research experience in digital signal processing, acoustic and perceptual correlates of dysphonic voices, forensic phonetics, musical acoustics, speech perception, and LED optics. Other interests are Brazilian choro music, bird photography, and sport fishing.
Hani Yehia
Universidade Federal de Minas Gerais, Brazil
Hani Camille Yehia holds the degrees of Electronics Engineer (ITA, 1988), Master of Electronic Eng. and Computer Science (ITA, 1992) and Doctor of Electrical Eng. (Nagoya University, 1997). From 1996 to 1998 he held the position of researcher at the ATR Laboratories (Japan) and, currently, holds the position of Professor at the Electronics Dept. of UFMG (Universidade Federal de Minas Gerais). From 2005 to 2009 he was the dean of the Graduate Program in Electrical Eng., from 2011 to 2013 was the head of Inova-UFMG Technology Incubator and, since 2018, is the dean of the Graduate Program in Neurosciences. He is the head of CEFALA
- Center for Research on Speech, Acoustics, Language and Music, developing research in Audiovisual production and perception of speech and Music; and member of CEMECH - Center for Research on Human Motion, Expression and Behavior; and of CTPMag - Center for Technology and Research on Magneto-Resonance. His research projects combine basic research in physics, neuroscience, linguistics and Music with applied research in audiovisual technologies of speech and Music.
Tim Brookes
University of Surrey, UK
Tim Brookes received the B.Sc. degree in mathematics and the M.Sc. and D.Phil. degrees in music technology from the University of York, York, U.K., in 1990, 1992, and 1997, respectively. He was employed as a Software Engineer, Recording Engineer and Research Associate before joining, in 1997, the academic staff at the Institute of Sound Recording, University of Surrey, Guildford, U.K., where he is now Senior Lecturer in Audio and Director of Research. His teaching focuses on acoustics and psychoacoustics and his research is in psychoacoustic engineering: measuring, modeling, and exploiting the relationships between the physical characteristics of sound and its perception by human listeners.
Russell Mason
University of Surrey, UK
Russell Mason was awarded a Ph.D. in audio engineering and psychoacoustics from the University of Surrey in 2002, and is currently a senior lecturer in the Institute of Sound Recording, University of Surrey, with over 100 published journal and conference papers. His research interests are focused on psychoacoustic engineering, and he has led the development of subjective evaluation methods and computational models of aspects of auditory perception, for application in spatial audio, evaluation of timbre, source separation, and personal sound zones.
