QTA to MP3

Convert iPhone Voice Memo / .qta recordings to MP3, right next to the originals. Despite the unusual extension, a .qta file is a QuickTime/MOV container holding an AAC audio track (often alongside an Apple spatial-audio apac track, which is ignored).

How it works

1. The recording is decoded with macOS's built-in afconvert (Core Audio) to a temporary WAV — no ffmpeg or Homebrew required.
2. The WAV is encoded to MP3 with a bundled, self-contained LAME encoder (bin/lame, a universal arm64 + x86_64 static binary, ad-hoc signed).
3. The temporary WAV is deleted.

The output is written beside the original (recording.qta → recording.mp3) and existing files are never overwritten. The resulting path is copied to the clipboard.

Usage

• Select one or more recordings in Finder, then run Convert QTA to MP3 from Coco — or run the command and pick files from the open panel.
• Encoding uses LAME VBR -V2 (~190 kbps), close to the source quality.

Notes

• Decoding produces a temporary uncompressed WAV roughly ~11.5 MB / minute of audio; the plugin checks for free space first and refuses the job if the volume is too small.
• Long conversions are cancellable from the progress HUD.

Licensing

The bundled bin/lame is LAME, licensed under the GNU LGPL v2 — see LICENSE-LAME.