Audio Convert

A OCaml CLI tool to convert audio files (.wav, .aif, .aiff, .flac, .m4a) to .mp3 and .ogg using ffmpeg, with optional silence trimming.

Requirements

• OCaml
• Dune
• System ffmpeg with libmp3lame and libvorbis encoders enabled

ffmpeg: System-installed with libmp3lame and libvorbis encoders enabled. Install via package manager:

• macOS: brew install ffmpeg
• Ubuntu/Debian: apt install ffmpeg libmp3lame0 libvorbisenc2
• Windows: Download from ffmpeg.org and add to PATH.

Installation

opam install . --deps-only

dune build

Command-line Options

Flag	Description	Default
-i, --input	Input file or directory (recursive if dir)	Required
-o, --output	Output directory (mirrors structure); if omitted, write next to inputs	Optional
--quality {low|medium|high|insane}	Quality preset	high
--mp3-bitrate <kbps>	Overrides preset for MP3 (e.g., 192)	Optional, uses preset if not set
--ogg-quality	Overrides preset for OGG Vorbis (int -1..10; e.g., 5)	Optional, uses preset if not set
--trim-silence	Enable silence removal (lead & tail)	Disabled
--silence-threshold <dB>	Silence threshold	-50
--silence-min-ms	Min silence duration (milliseconds)	200
--force	Overwrite existing outputs	Disabled
--dry-run	Print planned work, do not write	Disabled
-v, --verbose	More logs	Disabled
-h, --help	Show help	–

Examples

Single file

dune exec audio-convert -- -i samples/test.wav --quality high --trim-silence

Convert an entire directory

dune exec audio-convert -- -i ./audio_files -o ./out --quality medium

Overrides

dune exec audio-convert -- -i voice.wav --mp3-bitrate 192 --ogg-quality 5

Dry run

dune exec audio-convert -- -i ./in --dry-run

• silence-threshold : Threshold below which audio is considered silence (default: -50).
• silence-min-ms : Minimum duration of silence to trim (default: 200).