One-page reference: dialnorm range and attenuation math, ReplayGain (-18 LUFS) vs Opus (-23 LUFS) references, Apple Sound Check vs Spotify (metadata vs real-time), the normalize-vs-attenuate rule, and the FFmpeg loudnorm two-pass test commands.
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The book · Volume 4 of 7
Audio for Video: A Complete Guide to Sound in Video Products: From PCM and Codecs to Loudness, Accessibility, and Real-Time Voice Processing
This loudness in practice cheat sheet covers dialnorm math, ReplayGain and Opus references, Sound Check versus Spotify, and two-pass FFmpeg loudnorm tests. Volume 4 covers loudness end to end: LUFS and dynamic range, codec metadata in AAC and Opus, and real-time gain control. Written by Nikolay Sapunov, CEO at Fora Soft.
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