FFmpeg dynaudnorm Filter Offers Frame-by-Frame Audio Normalization Without Two Passes

FFmpeg's dynaudnorm filter addresses uneven audio levels across multi-source recordings by applying dynamic gain adjustments frame by frame, eliminating the need for two-pass processing. Unlike the loudnorm filter, which targets a fixed integrated loudness value for broadcast compliance, dynaudnorm works locally to balance quiet and loud segments relative to one another. The filter uses a Gaussian-weighted smoothing window to prevent abrupt gain shifts, producing natural-sounding transitions between frames. Key parameters such as frame length, Gaussian window size, and maximum gain can be tuned for specific use cases, including podcast production and speech content. Experts caution against setting maximum gain too high for speech, as it risks amplifying background silence, and recommend using loudnorm instead when broadcast LUFS targets are required.