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cli-audio-visualizer

v2.0.0

Published

CLI Audio Visualizer with volume and peak meter

Readme

🎧 CLI Audio Visualizer

Terminal-based audio visualizer built with Node.js. Real-time spectrum analysis, waveform rendering, and a volume/peak meter — all inside your terminal.


📸 Preview

Bars

Bars

Wave

Wave

Circle

Circle


✨ Features

  • 📊 Spectrum bars visualization
  • 🌊 Waveform view
  • 🔵 Circular visualization
  • 🔊 Real-time volume (RMS)
  • 📍 Peak meter with smooth decay
  • ⚡ Fast and lightweight
  • ⌨️ Keyboard controls

📦 Requirements

  • Node.js (>= 16)

Audio input:

  • macOS → ffmpeg
  • Linux → sox (rec command)

🔧 Installation

git clone 
cd node-cli
npm install

▶️ Usage

node index.js

🎮 Controls

| Key | Action | | ------- | ------------------------------- | | m | Switch visualization mode | | + / - | Increase / decrease sensitivity | | space | Pause / resume | | q | Quit |


🔊 Volume Meter

On the right side you will see:

  • Vol — current loudness (RMS)
  • Peak — maximum detected level (with smooth decay)

Example:

Vol : [██████████░░░░░░░░]
Peak:        |

🧠 How it works

  • Captures raw audio from system/microphone
  • Converts PCM → float samples
  • Uses FFT for frequency analysis
  • Calculates RMS for loudness
  • Applies smoothing for stable visualization
  • Renders UI using terminal graphics

⚙️ Configuration

You can tweak these values in the code:

const SAMPLE_RATE = 16000;
const FFT_SIZE = 1024;

📌 Notes

  • Works best in a large terminal window
  • Requires access to an audio input device
  • Peak meter uses exponential decay for smoother visuals

🚀 Future Improvements

  • 🎨 Gradient colors (green → yellow → red)
  • 🔴 Clip indicator
  • 📈 Auto gain normalization
  • 🎚️ Stereo support

📄 License

MIT