🎧 Apple Music Lossless Probe (macOS)

These tools classify your Apple Music library by the actual playback format (as reported by macOS/Music logs) and create Apple Music playlists per Sample Rate (SR) and Bit Depth (BD). They also save a timestamped CSV for analysis.

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📂 Files (key)

File	Purpose
probe_from_logs.py	Parses unified logs (Music/coreaudiod) to extract sample rate, bit depth, codec, tier, bitrate, etc.
playlist_by_format.sh	Plays each track briefly, probes logs, appends to CSV, and assigns into SR/BD/Codec/Tier playlists.
now_playing_title.py	Non-invasive now-playing title/artist/album probe via AppleScript (no playback control).

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🧰 Requirements

• macOS with the built-in Music app.
• Python 3 (pre-installed on macOS 12+).
• Full Disk Access for your terminal/app (to read unified logs)
  (System Settings ▸ Privacy & Security ▸ Full Disk Access).
• Automation permission for Music
  (System Settings ▸ Privacy & Security ▸ Automation).

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▶️ Usage

1. Make scripts executable

   chmod +x playlist_by_format.sh probe_from_logs.py now_playing_title.py

2. Run a small test (first 5 tracks, 2s settle)

   LIMIT_N=5 ./playlist_by_format.sh "" 2
   # Output goes to output/<YYYYMMDD-HHMMSS>-Library/results.csv

3. Scan a specific playlist (25 tracks, 3s settle)

   LIMIT_N=25 ./playlist_by_format.sh "My Playlist" 3

📄 Output

• A timestamped directory in output/:

  • results.csv columns:
    • source,track,artist,album,device_bit_depth,sample_rate_hz,bitrate_kbps,lpcm_kbps,channels,codec,tier
  • failures.csv (if any):
    • source,track,artist,album,persistent_id,reason

• Generated playlist artifacts per SR+BD combination:

  • CSV at output/<stamp>-<source>/results-organized/<name>.csv (deduped by persistent_id)
  • Apple Music playlist XML at output/<stamp>-<source>/playlists-xml/<name>.xml (import via Music: File → Library → Import Playlist…)
  • Example names: BD 24-bit + SR 48kHz, BD 24-bit + SR 96kHz, BD 16-bit + SR 44.1kHz, …

ℹ️ Notes

• Logs must be readable; grant Full Disk Access and re-run your terminal/app.
• For true rate switching, use a device/path that actually changes clock (e.g., USB DAC as clock source with an Aggregate/Multi-Output device; BlackHole for capture).
• This does not modify your library content; it only creates/updates organizational playlists.

⚙️ Behavior and environment variables

• Single-instance lock: the runner will auto-terminate any existing run by default (KILL_EXISTING=1).
  Override by setting KILL_EXISTING=0 if you prefer to abort when another run is active.
• Other useful environment variables:
  • LIMIT_N: cap number of tracks
  • PLAY_START_MAX_SECS (default 10): per-track deadline to ensure the intended PID is playing
  • PROBE_MAX_SECS (default 15): per-track probe deadline (logs stream)
  • POST_CAPTURE_SECS (default 1): brief extra window to fill codec/tier/channels