VoiceComment 2.0

Record a voice note and get a rectangle on your Excalidraw drawing that plays it.

The rectangle shows a self-contained HTML page with the audio inside — generated next to the MP3 and served by a small server the plugin runs on your own machine. It is always stopped: it never plays on its own, and it comes back when you reopen the drawing.

No ffmpeg, no Python, no cloud: the MP3 encoder ships inside the plugin.

One comment per idea, parked on the drawing itself.

Why

Neither Excalidraw nor its plugin can record audio, and even embedding an existing audio file in a drawing is a manual workaround — issue #2278 is still open, and the suggested workaround is to add a card and drop an audio link into it. VoiceComment does that for you, with the recording included: one comment per idea, parked exactly where you were.

What you get

Every recording writes two files into your vault folder:

and one element inside the drawing, which is what makes the rectangle come back.

The audio never plays by itself

Two guarantees, added up:

1. The generated page has no autoplay attribute.
2. Excalidraw creates the rectangle as a webview with autoplayPolicy=document-user-activation-required — the drawing plugin itself requires a user click before any sound.

Measured in the app after closing and reopening the drawing: the player comes back with the audio loaded and ready (readyState: 4), at currentTime: 0, paused: true, no autoplay. It only plays when you click it.

Requirements

• Obsidian 1.4.0 or newer, desktop version — the plugin keeps a small local server and opens its log through Electron, so it is marked desktop-only
• A microphone, and permission for Obsidian to use it
• The Excalidraw plugin, version 2.x, for the drawing part

Installation

Community plugins

Settings → Community plugins → Browse → search "VoiceComment 2.0" → Install → Enable.

BRAT

Add Engenharick/voicecomment to BRAT.

Manual

Download main.js, manifest.json and styles.css from the latest release, put them in <vault>/.obsidian/plugins/voicecomment/, and enable the plugin in Settings → Community plugins.

Usage

1. Open an Excalidraw drawing.
2. Click the microphone in the sidebar — or run VoiceComment 2.0: record audio and plot it on the drawing.
3. Talk. Click ■ Stop and plot to finish (or run the command again).
4. The rectangle appears in the middle of the view, with the audio already loaded and stopped.

The plugin deliberately ships no default hotkey, so it never steals a key you already use — assign one in Settings → Hotkeys if you prefer the keyboard.

Two extra commands help when things move around:

• Replot the last recording on the drawing — for when you closed the view before the rectangle was written
• Rebuild the HTML pages of this folder — regenerates the page of every MP3 in the recordings folder with the current player and colors

Settings

Limits (honest ones)

• This PC only. The rectangle shows a page served by the plugin running here. On another machine, or with Obsidian closed, the rectangle is empty — the MP3 and the HTML stay valid anywhere.
• Changing the port breaks the rectangles you already plotted: their URL is stored inside the drawing. If the port is busy, the plugin tries the next 10 and warns.
• The rectangle shows the browser's player inside a webview — not a native player.
• The drawing part needs the Excalidraw plugin; without it there is nothing to plot into.

Troubleshooting

• The rectangle is empty: check the diagnostic log. Every request the server answers is logged (servidor: GET /… .html -> 200 is what proves the page loaded). A port change is the usual cause.
• "the port was busy": another program (or another copy of the plugin) took 8781. The plugin moves to the next free port and warns that old rectangles may not load.
• "microphone permission denied": allow microphone access for Obsidian in your system privacy settings.
• "nothing was recorded": open the log — it records the AudioContext state, the captured byte counts and the peak level of every recording.

How it works

microphone → PCM (WebAudio) → lamejs → MP3 ─┬─> <name>.mp3  (in the vault)
                     └── MediaRecorder ──────┘
                                            └─> <name>.html (audio in base64)
                                                     ↑
    local server 127.0.0.1:8781 (this machine only) serves that folder
                                                     ↑
    an "embeddable" element in the drawing points to http://127.0.0.1:8781/<name>.html
    (Excalidraw sends any protocol link to a webview with the no-autoplay policy)

• Capture runs two parallel paths: raw PCM through WebAudio straight into the MP3 encoder (a single lossy generation), plus a MediaRecorder safety net. If the PCM path delivers nothing — a suspended AudioContext is the classic cause, and the timer keeps running anyway, which is misleading — the compressed capture is decoded with decodeAudioData and re-encoded. A recording is never lost.
• The server accepts only GET/HEAD, only from 127.0.0.1, and serves only files inside the recordings folder (no ../). Every request is written to the plugin log.

Development

powershell -File build.ps1                 # main.js = src/lame.min.js + src/audiohtml.js, then installs into the vault
powershell -File build.ps1 -Vault "C:\path\to\vault"
node --check main.js

Checking it with the app open (Obsidian.exe --remote-debugging-port=9333):

node tools\verificar-retangulo.js 9333 "<path\to\an.mp3>" apagar voicecomment
node tools\limpar-teste.js 9333          # if a test died halfway: deletes only zz-teste files

verificar-retangulo.js records through the plugin's real path, plots, checks the server log for the page load, closes and reopens the drawing to prove the rectangle comes back — and deletes only the zz-teste- files it created. With a heavily loaded vault the reopen step can be slow: it fails soft, prints what it measured and still cleans up.

Credits

• lamejs (LGPL-3.0) — MP3 encoding, bundled unmodified. See THIRD-PARTY-NOTICES.md.
• Excalidraw for Obsidian by Zsolt Viczián — the ExcalidrawAutomate API that makes the drawing part possible.

License

LGPL-3.0 — see LICENSE.