FFmpeg Cookbook
Audio Fade-In and Fade-Out with the afade Filter
Create smooth audio fades in FFmpeg with the afade filter. Covers start time, duration, curve types, applying fades to video audio tracks, and combining fade-in with fade-out in one command.
Loudness Normalization — EBU R128 with the loudnorm Filter
Normalize audio to EBU R128 standard with FFmpeg loudnorm filter. Single-pass and two-pass measurement modes. Key parameters: I (integrated LUFS), TP, and LRA.