headroom analyzes audio files for loudness (LUFS) and headroom, then applies lossless gain adjustment. It supports MP3, AAC/M4A, FLAC, AIFF, and WAV files. Features include batch processing, ReplayGain analysis, lossless MP3 gain via mp3rgain, lossless AAC/M4A gain adjustment, and a scriptable non-interactive CLI mode for pipelines and CI. v2.0.0 adds the rbsort subcommand, which sorts a Rekordbox collection.xml export by Camelot Key and BPM for harmonic mixing prep — no audio touched, no ffmpeg required.
