ExpedusTM DVA Loudness Analysis License – ITU BS.1770
Audio Quality Testing
Loudness analysis is an important aspect of subjective audio quality assessment.
Video encoding and transcoding require understanding:
· Volume settings for the travel video program
· Volume status of multiple programs
- Volume changes of the same program during playback
ITU BS.1770 provides a standardized algorithm for measuring loudness and True Peak.
Dialnorm is a metadata parameter for Dolby AC-3 encoding. Dolby recommends that the Dialnorm value should be set based on the average dialogue level of each video program.
In the deployment of digital television in North America, ATSC A/85 recommends ITU BS.1770 as the standard for program loudness monitoring; ATSC A/53 Annex B mandates that operators monitor Dialnorm as a requirement.
In response to complaints from television users regarding ad volume, the U.S. FCC requires operators to conduct ongoing monitoring in accordance with ATSC A/85 and its subsequent standards.