Voxi

Lightweight Windows text-to-speech tray app using SAPI, with an optional private offline Narrator voice backend.

Features

• Read clipboard text aloud via hotkey
• Cycle between Microsoft Guy and Microsoft Eva
• Prewarmed Microsoft Guy natural voice at native SAPI rate 10
• Adjustable speech speed
• Built-in pronunciation dictionary for URLs, acronyms, emojis
• Read Markdown content & link labels without formatting noise
• Decode HTML entities & expand numeric multiplication and common math symbols
• Preserve punctuation & following text when shortening URLs
• Text filters: All, None or per-category control from the tray menu
• Remembers voice, speed & text filters between runs
• Queue 2 seconds of silent audio after speech to help with Bluetooth end clipping
• Idle and speaking tray states with embedded white line icons
• Compact native menu with transparent colored line icons
• Single-instance protection and automatic tray recovery after Explorer restarts

Hotkeys

• Alt+1 - Toggle read/stop
• Alt+2 - Cycle speed
• Alt+3 - Cycle voice
• Alt+4 - Exit

Voxi hotkeys do not open the foreground app's menu bar when Alt is released. Bare Alt still works normally.

The menu shows Read while idle & Stop while speaking, including live updates while open. Read uses a speech bubble & Stop uses a stop square. Selecting Stop never starts another reading. The voice menu shows Eva or Guy; changes announce only the voice's first name: Eva or Guy.

Changing speed while reading preserves your place. Eva changes speed directly; Guy resumes at the current word because its embedded engine cannot adjust an utterance already in progress. Guy may repeat that word. The speed presets are Slow, Mid & Fast (SAPI rates 0, 5 & 10). Speed announcements replace earlier announcements immediately; only clipboard readings are resumed.

The silent tail uses PCM audio on the same speech output for both voices. Guy's embedded engine ignores XML silence tags. This is an app-side workaround; whether it resolves Bluetooth clipping depends on the audio device & driver. During the silent tail, the tray icon is idle. Alt+1 starts the next reading immediately & Alt+2 announces the new speed, replacing the remaining silence.

Text filters

Right-click the tray icon & open Filters to toggle categories or choose a preset:

• Cleanup shortens links, reads Markdown without formatting, decodes HTML entities & drops copied UI prompts that sit on their own line.
• Pronunciation fixes names & reads math symbols such as !=, ≤ & 2*3.
• Acronyms expands shorthand such as AFAIK & a standalone uppercase FR.
• Emoji reads common emoji as words.
• None reads the clipboard exactly as copied.
• All applies every filter above.

Changing categories individually shows Custom. Voice & speed announcements always use All. None still replaces control characters & escapes XML so every voice gets valid input. Voxi saves the voice, speed & filters to %APPDATA%\Voxi\settings.txt.

Install

Download voxi-*-windows-x64.zip from Releases, extract it to a permanent folder, & run Voxi.exe. The portable package uses installed SAPI voices; Microsoft Guy is an optional separate download.

To add Guy, exit Voxi & run this from the extracted folder:

powershell -ExecutionPolicy Bypass -File scripts/setup-guy.ps1

Each release includes a .sha256 file. Compare its value with Get-FileHash .\voxi-*-windows-x64.zip -Algorithm SHA256 before extracting.

Build

Voxi requires Windows, Rust 1.80 or newer, and the Windows SDK resource compiler.

cargo build --release --locked

The executable is written to target/release/Voxi.exe.

Microsoft Guy is loaded when runtime/natural is installed beside Voxi.exe. Voxi uses registration-free COM activation and does not register the adapter system-wide. Guy is the default and first voice, with Eva second as the lightweight SAPI fallback. If Guy cannot initialize or later rejects a speech request, Voxi switches to Eva and keeps working.

To install Guy from the adapter's official release and Microsoft's official US English voice package:

powershell -ExecutionPolicy Bypass -File scripts/setup-guy.ps1 -Destination .\target\release\runtime\natural

The script verifies both downloads by SHA-256 and extracts only the 64-bit runtime files Voxi needs. The downloaded Microsoft files remain outside version control. See THIRD_PARTY_NOTICES.md for source and license details.

Development

cargo fmt -- --check
cargo test --all-targets --locked
cargo clippy --all-targets --locked -- -D warnings

Releases

Run pwsh -NoProfile -File scripts/package.ps1 to build a Windows x64 ZIP & SHA-256 checksum in dist/. Packaging requires PowerShell 7 & the x86_64-pc-windows-msvc Rust target. It includes setup instructions & licenses, but excludes downloaded Microsoft components.

Update the version in Cargo.toml & Cargo.lock, merge the change, then push a matching vX.Y.Z tag. CI checks formatting, tests, & Clippy before packaging that exact revision & creating a draft GitHub release. Review its notes & ZIP before publishing.

License

MIT