lavaspectro

A Lavalink v4 plugin that pre-calculates spectrogram data for audio tracks, perfect for TUI visualizers or web-based bars.

Quick Start

1. Download: Get the latest .jar from the GitHub Releases page.
2. Install: Drop the .jar into your Lavalink plugins/ folder.
3. Restart: Start Lavalink. The plugin will be active.

API Endpoint

GET /v4/plugins/spectrogram/{trackId}

• trackId: The base64 encoded track string from Lavalink.
• Returns: A 2D JSON array number[][].
• Inner arrays contain 64 frequency bands (0-255).
• Each frame represents ~42ms of audio.

Lavalink Configuration

The plugin is hosted via JitPack, allowing for easy integration without needing GitHub personal access tokens.

Stable Version

To use the official stable release:

lavalink:
  plugins:
    - dependency: "team.firefly.lavalink.lavaspectro:lavaspectro-plugin:1.0.0"
      repository: "https://maven.xserv.pp.ua/releases"

Development (Snapshot) Version

To use the latest development build generated on every push:

lavalink:
  plugins:
    - dependency: "team.firefly.lavalink.lavaspectro:lavaspectro-plugin:1.0.0-SNAPSHOT"
      repository: "https://maven.xserv.pp.ua/snapshots"
      snapshot: true

Usage (TypeScript + Lavacord)

import axios from 'axios';

async function getSpectrogram(node: any, trackEncoded: string) {
    const url = `http://${node.host}:${node.port}/v4/plugins/spectrogram/${encodeURIComponent(trackEncoded)}`;
    
    try {
        const response = await axios.get(url, {
            headers: {
                Authorization: node.password
            }
        });
        
        return response.data; // number[][]
    } catch (err) {
        console.error("Failed to fetch spectrogram:", err);
    }
}

Building

Requires JDK 21.

# Standard build
./gradlew build

# Snapshot build
./gradlew build -Psnapshot

Output jar is located in build/libs/.