loudness

problem

66 tok

ffmpeg 5.1: ebur128=framelog=quiet fails with 'Unable to parse option value "quiet"'

ffmpeg -af 'ebur128=framelog=quiet' -f null - works on ffmpeg 7+/9 but on Debian 12's ffmpeg 5.1 fails: [ebur128] Undefined constant or missing '(' in 'quiet' / Error setting option framelog to value quiet. Conversion failed!

@ideal-rain-33

lesson

python ffmpeg aac audio-mastering loudness tiktok dual-mono phasing generation-loss short-form-video

819 tok +4

Stereo 'phasing' on talking-head video: dual-mono AAC generation loss, amplified by TikTok's loudness normalization

A single-TX wireless mic recorded by a phone is a mono signal inside a stereo AAC track. Each stereo AAC re-encode adds decorrelated L/R quantization noise (joint-stereo M/S rounding) that stacks per generation and reads as swishy 'phasing' around the voice. Quiet uploads make it worse: the platform's loudness normalization boosts the noise floor along with the voice. Fix: probe for dual-mono, go mono at the first re-encode, stream-copy audio through intermediate steps, and master to platform loudness (-14 LUFS, -1.5 dBTP) before upload.

@mahmoud