Speech Intelligibility and Audio Monitoring in OTT

Metadata

Publisher: SMPTE
Doc Type: Journal Article
Content Type: Original Research
Abbreviated Title: SMPTE Motion Imaging Jour.
Volume: 134, No. 3, pp. 22–25
Abstract: The paper details ways of controlling speech loudness and speech intelligibility in Over-the-Top (OTT) and broadcast production, primarily based on a new metric, Loudness-to-Dialog ratio (LDR), and calibrated sound monitoring at a moderate listening level. Principles of loudness normalization are described as a study that defines and quantifies LDR for use in broadcast and OTT. Findings may be applied during mixing or dubbing, used for default settings in Next-Generation Audio (NGA) delivery, and automated Quality Control (QC) as a machine learning indicator.
Publication Date: 2025-05-01
DOI: 10.5594/JMI.2025/EWDC4700
ISSN: Print: 1545-0279 | Electronic: 2160-2492
Link: https://doi.org/10.5594/JMI.2025/EWDC4700
Author(s): Thomas Lund
Keyword(s): Loudness To Dialog Ratio (LDR), Definition of Dialog Level, Listening Level in Production
Copyright: © 2025 SMPTE

Bibliographic Reference(s)

EBU.R128.2023 — European Broadcasting Union (EBU) R128: Loudness Normalisation And Permitted Maximum Level of Audio Signals, (2023). EXTERNAL
S. H. Nielsen and T. Lund, “Overload in Signal Conversion,” Proc. AES 23rd Int. Conf., Elsinore, Denmark, 2003. EXTERNAL
T. Lund, “Stop Counting Samples,” Proc. AES 121st Conv., San Francisco, CA, 2006. EXTERNAL
G. Soulodre, “Evaluation of Objective Loudness Meters,” Proc. AES 116th Int. Conv., Berlin, Germany, 2004. EXTERNAL
International Telecommunication Union-Radiocommunication (ITU-R), BS.1770 “Algorithms to Measure Audio Programme Loudness and True-Peak Audio Level, Geneva, Switzerland, 2023. EXTERNAL
International Telecommunication Union-Radiocommunication (ITU-R), BS.1771 “Requirements for Loudness and True-Peak Indicating Meters,” Geneva, Switzerland, 2012. EXTERNAL
E. Skovenborg and S. H. Nielsen, “Evaluation of Different Loudness Models with Music and Speech Material,” Proc. AES 117th Int. Conv., San Francisco, CA, 2004. EXTERNAL
E. Skovenborg and T. Lund, “Loudness Descriptors to Characterize Wide Loudness-Range Material,” Proc. AES 127th Int. Conv., New York, NY, 2009. EXTERNAL
K. Küpfmüller, „Nachrichtenverarbeitung im Menschen,” in Taschenbuch der Informatik, Springer, 1974 (orig. 1962). EXTERNAL
C. Coupé, “Different Languages, Similar Encoding Efficiency: Comparable Information Rates Across the Human Communicative Niche,” Sci. Adv., 2019. EXTERNAL
T. Lund and A. Mäkivirta, “On Human Perceptual Bandwidth and Slow Listening,” Tonmeistertagung Conf. Paper, 2018. EXTERNAL
F. Camerer, “Loudness Normalisation of Cinematic Content,” EBU Recommendation R128 s4, Geneva, Switzerland, 2023. EXTERNAL
E. Skovenborg and T. Lund, “Level Normalization of Feature Films using Loudness vs. Speech,” Proc. AES 135th Int. Conv., New York, NY, 2013. EXTERNAL
European Norm/International Electrotechnical Commission (EN/IEC) 62368-1, Requirements for Personal Music Players, Safety Standard, Bruxelles, Belgium, 2023. EXTERNAL

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Thomas Lund; Speech Intelligibility and Audio Monitoring in OTT, MIJ 2025, Volume 134, Number 3 (pp. 22 to 25); SMPTE, 2025. Available at https://doi.org/10.5594/JMI.2025/EWDC4700

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Thomas Lund; Speech Intelligibility and Audio Monitoring in OTT, MIJ 2025, Volume 134, Number 3 (pp. 22 to 25); SMPTE, 2025. Available at https://doi.org/10.5594/JMI.2025/EWDC4700

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Thomas Lund; Speech Intelligibility and Audio Monitoring in OTT, MIJ 2025, Volume 134, Number 3 (pp. 22 to 25); SMPTE, 2025. Available at https://doi.org/10.5594/JMI.2025/EWDC4700

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<span class="citation">Thomas Lund; <cite>Speech Intelligibility and Audio Monitoring in OTT</cite>, MIJ 2025, Volume 134, Number 3 (pp. 22 to 25); SMPTE, 2025. Available at <a href="https://doi.org/10.5594/JMI.2025/EWDC4700" target="_blank" rel="noopener">https://doi.org/10.5594/JMI.2025/EWDC4700</a></span>

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Thomas Lund; Speech Intelligibility and Audio Monitoring in OTT, MIJ 2025, Volume 134, Number 3 (pp. 22 to 25); SMPTE, 2025
doi: 10.5594/JMI.2025/EWDC4700
url: https://doi.org/10.5594/JMI.2025/EWDC4700

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<li>
Thomas Lund; <cite id="bib-10-5594-jmi-2025-ewdc4700">Speech Intelligibility and Audio Monitoring in OTT</cite>, MIJ 2025, Volume 134, Number 3 (pp. 22 to 25); SMPTE, 2025
<span class="doi">10.5594/JMI.2025/EWDC4700</span>
</li>