A desktop audio spectrogram viewer built with Rust and egui.
- Drag & drop or click Open to load audio files
- Supports MP3, WAV, FLAC, OGG, M4A, AAC, Opus, WMA, AIFF, AU
- Linear / Logarithmic frequency axis toggle
- dB range sliders — adjustable ceiling and floor with reset
- Overlap control — 0 %, 50 %, or 75 % FFT window overlap
- Channel modes — Mix, L, R, or L+R split view
- Hover info — time, frequency, nearest musical note, and dB at cursor
- Export PNG — 1400 × 800 spectrogram image (Cmd/Ctrl+S or Save PNG button)
- SoX-style color palette
macOS (Homebrew)
brew tap zanets/tap
brew install spektraOther platforms — pre-built binaries for macOS (Apple Silicon) and Windows (x64) are available on the Releases page.
- Rust stable toolchain
- FFmpeg libraries
macOS (Homebrew)
brew install ffmpeg lame x264 x265 svt-av1 dav1d opus libvpx libvmaf
cargo build --releaseWindows (vcpkg)
vcpkg install ffmpeg:x64-windows-static
$env:FFMPEG_DIR = "$env:VCPKG_INSTALLATION_ROOT\installed\x64-windows-static"
cargo build --releaseThe binary is written to target/release/spektra (or spektra.exe on Windows).
| Action | How |
|---|---|
| Open file | Drag & drop onto the window, or click Open |
| Save PNG | Press Cmd/Ctrl+S, or click Save PNG |
| Toggle frequency scale | Click Freq: Lin / Freq: Log |
| Adjust dB range | Move the Ceil and Floor sliders |
| Reset dB range | Click the ↺ button |
| Change overlap | Select from the OL dropdown |
| Change channel | Select from the Mix / L+R / L / R dropdown |
Hover over the spectrogram to see a crosshair with time, frequency, musical note, and dB value.
| Parameter | Value |
|---|---|
| FFT size | 2048 points |
| Window | Hann |
| Frequency bands | 1025 |
| Time columns | 800 |
| Color palette | SoX |
| Export resolution | 1400 × 800 px |
Audio decoding is handled by ffmpeg-next. Mono files are upmixed to stereo internally.
MIT