AVAudioConverter keeps only channel 1 when downmixing stereo and outputs pure silence for layout-less multi-channel inputs (e.g. a 4-input USB interface such as the UA Volt 476P), so the dictation model heard nothing and the HUD never showed text. Pick the channel that carries the voice (loudest on smoothed energy, switching only on a clear 6 dB margin) and convert it as mono. Also reserve the dictation locale, which the Speech framework warns will become required, and log the mic format. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
WhisperDictate
A simple menu bar app for voice dictation using OpenAI Whisper (local, offline).
Platforms
| Platform | Language | Status |
|---|---|---|
| macOS | Swift | ✅ Ready |
| Linux | Rust | 🔜 Planned |
| Windows | C# | 🔜 Planned |
macOS
What's new in 1.4.0
- 💬 Live preview while recording — the recording overlay shows what you're saying as you speak, using macOS's on-device dictation model (works in Hungarian too). It's a preview: the pasted text still comes from Whisper, so it can differ slightly. Toggle it in Settings.
What's new in 1.3.1
- 🪶 Quantized models — Large v3 Turbo q5_0 keeps the transcription server at ~0.7 GB RAM instead of ~1.75 GB, at the same speed (also Small q5_1, Medium q5_0, Turbo q8_0 and Large v3 q5_0)
- 📥 Download progress window — progress bar, size, speed, time remaining, Cancel/Retry; progress also shows in the menu bar and Settings
- 🔥 Model warm-up at recording start — if the model was paged out after a pause, it starts loading as soon as you start talking, not after you stop; the HUD tells you when a transcription is slower because the model is still loading
What's new in 1.3.0
- ⚡ Warm transcription server — the Whisper model stays loaded in a background
whisper-server, so each dictation is a fast local call (~0.5s) instead of reloading the 1.5–1.6 GB model on every utterance - 📊 Live mic-level HUD while recording, which warns ("No audio input?") if the microphone stays silent
- 📖 Custom dictionary — an editable Heard → Replacement table that fixes names/jargon in the transcript and also biases recognition
Features
- 🎤 Global hotkey (⌃⌥D) to start/stop recording
- ⚡ Fast transcription via a warm whisper-server (model stays loaded — no per-dictation reload), with automatic fallback to
whisper-cli - 📊 Live mic-level meter while recording, with a "no audio input" warning
- 💬 Live transcript preview in the recording overlay (on-device Apple dictation model; Whisper still produces the pasted text)
- 📖 Custom dictionary (heard → replacement) that also biases recognition
- 🔒 Fully offline - uses local Whisper model
- ⌨️ Automatic paste into any focused app
- 📋 Clipboard preservation - your copied content is restored after paste
- ⚙️ Settings window with model selection dropdown
- 📥 Built-in model downloader with a progress window (speed, time remaining, cancel/retry)
- 🪶 Quantized model options for much lower memory use
- 🚀 Launch at login support
- 🔊 Sound feedback (optional)
- 📦 Self-contained - whisper-cli and whisper-server bundled in the app
Requirements
- macOS 26 (Tahoe) or later
- Apple Silicon (M1/M2/M3) or Intel Mac
Quick Install (Download)
- Download the latest DMG from Releases
- Open the DMG and drag WhisperDictate to Applications
- Launch WhisperDictate
- On first run, select and download a Whisper model
- Grant permissions (Microphone + Accessibility)
Build from Source
# Clone the repository
git clone https://github.com/hariel1985/WhisperDictate.git
cd WhisperDictate/macos
# Install whisper-cpp (required for bundling)
brew install whisper-cpp
# Build and install to /Applications
make install
Build Commands
| Command | Description |
|---|---|
make build |
Compile the app and bundle whisper-cli |
make install |
Build and install to /Applications |
make run |
Build and run |
make dmg |
Create distributable DMG |
make clean |
Remove build artifacts |
Usage
- Launch WhisperDictate from Applications
- Look for the 🎤 icon in your menu bar
- Press ⌃⌥D (Control + Option + D) to start recording
- Speak (icon changes to 🔴)
- Press ⌃⌥D again to stop and transcribe
- Text is automatically pasted where your cursor is
Settings
Click the menu bar icon → Settings to configure:
- Language: Auto-detect or 31 supported languages
- Model: Select from installed models or download new ones (✓ marks models already downloaded)
- Dictionary: Add Heard → Replacement pairs to fix names/jargon (use
\nfor a newline); the replacement terms also improve recognition - Sound feedback: Toggle audio feedback on/off
- Live preview while recording: Show a rough live transcript in the recording overlay (on by default)
- Launch at login: Start automatically when you log in
Whisper Models
Download models directly from the app or manually:
| Model | Size | Speed | Accuracy | Best For |
|---|---|---|---|---|
| Tiny | 75 MB | ~1 sec | Basic | Quick tests, simple phrases |
| Base | 142 MB | ~2 sec | Good | Clear speech, quiet environment |
| Small | 466 MB | ~3 sec | Better | General use, some accents |
| Medium | 1.5 GB | ~5 sec | Great | Accents, noisy audio |
| Large v3 Turbo | 1.6 GB | ~4 sec | Best | Recommended - fast like Medium, accurate like Large |
| Large v3 | 3.1 GB | ~8 sec | Maximum | Difficult audio, max accuracy |
Quantized variants (q5/q8) have much smaller weights, so the model uses far less memory, with a small accuracy trade-off:
| Model | Size | Full-size equivalent |
|---|---|---|
| Small q5_1 | 181 MB | Small (466 MB) |
| Medium q5_0 | 514 MB | Medium (1.5 GB) |
| Large v3 Turbo q5_0 | 547 MB | Large v3 Turbo (1.6 GB) — measured ~0.7 GB RAM vs ~1.75 GB, same speed |
| Large v3 Turbo q8_0 | 833 MB | Large v3 Turbo (1.6 GB) — near-identical accuracy |
| Large v3 q5_0 | 1.0 GB | Large v3 (3.1 GB) |
Models are stored in ~/.whisper-models/
With the warm server (1.3.0+), the selected model loads once at startup (a few seconds); after that each dictation skips the reload, so the speeds above are roughly the per-dictation transcription time.
The server keeps the whole model in memory while it runs. If macOS pages it out after a long pause, 1.3.1+ starts loading it back as soon as you start recording, and the HUD shows "Loading model into memory…" if that takes a moment.
Audio Feedback
- 🔔 Tink - Recording started
- 🔔 Pop - Recording stopped, processing
- 🔔 Glass - Success, text pasted
- 🔔 Basso - Error
Permissions
Grant these in System Settings → Privacy & Security:
| Permission | Why it's needed |
|---|---|
| Microphone | To record your voice for transcription |
| Accessibility | To simulate ⌘V keystroke and paste text into any app. macOS requires this permission for apps that send keyboard events to other applications. |
Note
: After reinstalling or updating, you may need to remove and re-add the app in Accessibility settings.
Security
- All processing is done locally - no data leaves your device
- The live preview uses macOS's on-device dictation model (SpeechAnalyzer); it needs no extra permission beyond the microphone
- The bundled
whisper-serveris bound to127.0.0.1(loopback only) and is never exposed on the network - Audio files are stored in private temp directory and deleted after transcription
- Clipboard is cleared after paste (transcript doesn't remain accessible)
- Original clipboard content is preserved and restored after paste
- Input validation prevents command injection
- No network access except for optional model downloads from Hugging Face
License
MIT License