📊 Chart To Image

Convert trading charts to images using Node.js Canvas, lightweight-charts, and CCXT. A powerful Node.js library for generating high-quality trading chart images from market data.

📊 Chart Types Demo

| Candlestick | Line | Area | |-------------|------|------| | | | |

| Heikin-Ashi | Renko | |-------------|-------| | | |

🔄 Comparison Charts

Features

• 📊 Real Market Data: Fetch live data from multiple exchanges via CCXT
• 🎨 High-Quality Charts: Generate professional charts using lightweight-charts
• 🖼️ Multiple Formats: Export to PNG and JPEG formats using Node.js Canvas
• ⚡ Fast & Lightweight: Optimized for performance and minimal dependencies
• 🔧 Flexible API: Both programmatic API and CLI interface
• 📦 Easy Integration: Simple npm install and import
• 🎨 Custom Bar Colors: Customize bullish/bearish candle colors
• 📈 Horizontal Levels: Add support/resistance levels with labels
• 🌈 Advanced Chart Types: Candlestick, Line, Area, Heikin-Ashi, Renko, Line Break
• 🎯 Custom Themes: Light/Dark themes with custom colors
• 👁️ Hide Elements: Hide title, time axis, and grid
• 🎨 Color Customization: Hex, RGB, named colors, and gradients
• 📏 Scaling Options: Auto-scaling and manual scale factors
• 🔄 Multiple Exchanges: Binance, Kraken, Coinbase, and more
• 🔄 Chart Comparison: Side-by-side and grid layouts for multiple symbols
• ⏰ Timeframe Comparison: Same symbol across different timeframes
• 🎨 Comparison Customization: Custom colors and themes for comparisons
• 📊 Technical Indicators: VWAP, EMA, SMA, and Bollinger Bands with custom colors

🛠️ Technologies Used

• Node.js Canvas: High-performance 2D graphics rendering
• lightweight-charts: Professional trading chart library
• CCXT: Unified cryptocurrency exchange API
• TypeScript: Type-safe development
• ESLint: Code quality and consistency

📦 Installation

npm install @neabyte/chart-to-image

🚀 Quick Start

💻 CLI Usage

# Basic chart generation
npx @neabyte/chart-to-image --symbol BTC/USDT --output chart.png

# Custom timeframe and dimensions
npx @neabyte/chart-to-image -s ETH/USDT -t 4h -o eth-chart.png -w 1200 -h 800

# With custom theme and colors
npx @neabyte/chart-to-image -s BTC/USDT -o chart.png --theme dark --background-color "#1a1a2e" --text-color "#00d4ff"

# Advanced chart types
npx @neabyte/chart-to-image -s ETH/USDT -o heikin-ashi.png --chart-type heikin-ashi
npx @neabyte/chart-to-image -s BTC/USDT -o renko.png --chart-type renko
npx @neabyte/chart-to-image -s BTC/USDT -o line-break.png --chart-type line-break

# Technical indicators
npx @neabyte/chart-to-image -s BTC/USDT -o vwap-chart.png --vwap
npx @neabyte/chart-to-image -s ETH/USDT -o ema-chart.png --ema
npx @neabyte/chart-to-image -s BTC/USDT -o sma-chart.png --sma
npx @neabyte/chart-to-image -s BTC/USDT -o indicators.png --vwap --ema --sma

# Bollinger Bands with custom colors
npx @neabyte/chart-to-image -s BTC/USDT -o bb-chart.png --bb
npx @neabyte/chart-to-image -s ETH/USDT -o bb-custom.png --bb --bb-upper-color "#ff6b9d" --bb-middle-color "#4ecdc4" --bb-lower-color "#ff6b9d" --bb-background-color "#ff6b9d" --bb-background-opacity 0.2
npx @neabyte/chart-to-image -s BTC/USDT -o bb-line.png --bb --chart-type line --bb-upper-color "#9b59b6" --bb-middle-color "#f39c12" --bb-lower-color "#9b59b6" --bb-background-color "#9b59b6" --bb-background-opacity 0.25

# All indicators together
npx @neabyte/chart-to-image -s BTC/USDT -o all-indicators.png --vwap --ema --sma --bb

# Chart comparison (side-by-side)
npx @neabyte/chart-to-image --compare "BTC/USDT,ETH/USDT" --output comparison.png

# Timeframe comparison (same symbol, different timeframes)
npx @neabyte/chart-to-image --compare "BTC/USDT,BTC/USDT" --timeframes "1h,4h" --output timeframe-comparison.png

# Grid comparison with custom colors
npx @neabyte/chart-to-image --compare "BTC/USDT,ETH/USDT" --layout grid --custom-colors "bullish=#00ff88,bearish=#ff4444" --output grid-comparison.png

# Comparison with indicators
npx @neabyte/chart-to-image --compare "BTC/USDT,ETH/USDT" --vwap --ema --output comparison-indicators.png

# Comparison with Bollinger Bands
npx @neabyte/chart-to-image --compare "BTC/USDT,ETH/USDT" --bb --output comparison-bb.png
npx @neabyte/chart-to-image --compare "BTC/USDT,ETH/USDT" --bb --bb-upper-color "#ff6b9d" --bb-middle-color "#4ecdc4" --bb-lower-color "#ff6b9d" --bb-background-color "#ff6b9d" --bb-background-opacity 0.2 --output comparison-bb-custom.png

# Hide elements for clean charts
npx @neabyte/chart-to-image -s ADA/USDT -o clean.png --hide-title --hide-time-axis --hide-grid

🔧 Programmatic API

import { quickChart, generateChartImage, fetchMarketData, ComparisonService } from '@neabyte/chart-to-image'

// Quick chart generation
const result = await quickChart('BTC/USDT', 'chart.png', {
  timeframe: '1h',
  width: 1200,
  height: 800,
  theme: 'dark'
})

// Advanced configuration
const config = {
  symbol: 'ETH/USDT',
  timeframe: '4h',
  exchange: 'binance',
  outputPath: 'eth-chart.png',
  width: 1000,
  height: 600,
  theme: 'light',
  chartType: 'heikin-ashi',
  backgroundColor: '#1a1a2e',
  textColor: '#00d4ff',
  customBarColors: {
    bullish: '#00ff88',
    bearish: '#ff4444',
    wick: '#ffffff',
    border: '#333333'
  },
  showTitle: false,
  showTimeAxis: false,
  showGrid: false
}

const result = await generateChartImage(config)

// Chart comparison
const comparisonResult = await ComparisonService.sideBySide(
  ['BTC/USDT', 'ETH/USDT'],
  'comparison.png'
)

// Timeframe comparison
const timeframeResult = await ComparisonService.timeframeComparison(
  'BTC/USDT',
  ['1h', '4h', '1d'],
  'timeframe-comparison.png'
)

// Grid comparison with custom colors
const gridResult = await ComparisonService.grid(
  ['BTC/USDT', 'ETH/USDT'],
  2,
  'grid-comparison.png',
  {
    customBarColors: {
      bullish: '#00ff88',
      bearish: '#ff4444'
    }
  }
)

// Chart with technical indicators
const indicatorResult = await generateChartImage({
  symbol: 'BTC/USDT',
  timeframe: '1h',
  outputPath: 'indicators.png',
  showVWAP: true,
  showEMA: true,
  emaPeriod: 20,
  showSMA: true,
  smaPeriod: 20
})

// Chart with Bollinger Bands
const bbResult = await generateChartImage({
  symbol: 'BTC/USDT',
  timeframe: '1h',
  outputPath: 'bb-chart.png',
  showBollingerBands: true,
  bbPeriod: 20,
  bbStandardDeviations: 2,
  bbColors: {
    upper: '#ff6b9d',
    middle: '#4ecdc4',
    lower: '#ff6b9d',
    background: '#ff6b9d',
    backgroundOpacity: 0.2
  }
})

// All indicators together
const allIndicatorsResult = await generateChartImage({
  symbol: 'BTC/USDT',
  timeframe: '1h',
  outputPath: 'all-indicators.png',
  showVWAP: true,
  showEMA: true,
  emaPeriod: 20,
  showSMA: true,
  smaPeriod: 20,
  showBollingerBands: true,
  bbPeriod: 20,
  bbStandardDeviations: 2,
  bbColors: {
    upper: '#ff6b9d',
    middle: '#4ecdc4',
    lower: '#ff6b9d',
    background: '#ff6b9d',
    backgroundOpacity: 0.2
  }
})

// Comparison with indicators
const comparisonWithIndicators = await ComparisonService.sideBySide(
  ['BTC/USDT', 'ETH/USDT'],
  'comparison-indicators.png',
  {
    showVWAP: true,
    showEMA: true,
    emaPeriod: 20,
    showSMA: true,
    smaPeriod: 20
  }
)

// Comparison with Bollinger Bands
const comparisonWithBB = await ComparisonService.sideBySide(
  ['BTC/USDT', 'ETH/USDT'],
  'comparison-bb.png',
  {
    showBollingerBands: true,
    bbPeriod: 20,
    bbStandardDeviations: 2,
    bbColors: {
      upper: '#ff6b9d',
      middle: '#4ecdc4',
      lower: '#ff6b9d',
      background: '#ff6b9d',
      backgroundOpacity: 0.2
    }
  }
)

⚡ Advanced Features

📊 Chart Types

• Candlestick: Traditional OHLC candles
• Line: Simple line chart
• Area: Filled area chart
• Heikin-Ashi: Trend-smoothed candles
• Renko: Price-based block chart
• Line Break: Break high/low trend patterns

📈 Technical Indicators

• VWAP: Volume Weighted Average Price (institutional standard)
• EMA: Exponential Moving Average (configurable periods)
• SMA: Simple Moving Average (configurable periods)
• Combined Analysis: Use all indicators together for comprehensive analysis

🎨 Custom Colors

# Hex colors
--background-color "#1a1a2e" --text-color "#00d4ff"

# RGB colors
--background-color "rgb(25, 25, 112)" --text-color "rgb(255, 215, 0)"

# Named colors
--background-color "midnightblue" --text-color "gold"

# Gradients
--background-color "linear-gradient(135deg, #667eea 0%, #764ba2 100%)"

👁️ Hide Elements

# Hide title
--hide-title

# Hide time axis
--hide-time-axis

# Hide grid
--hide-grid

# Hide all elements
--hide-title --hide-time-axis --hide-grid

📏 Scaling Options

# Auto-scaling
--auto-scale

# Manual scaling
--scale-x 1.2 --scale-y 1.1

# Price limits
--min-scale 45000 --max-scale 50000

🏢 Supported Exchanges

• Binance
• Coinbase
• Kraken
• KuCoin
• OKX

⏰ Supported Timeframes

• 1m (1 minute)
• 5m (5 minutes)
• 15m (15 minutes)
• 30m (30 minutes)
• 1h (1 hour)
• 4h (4 hours)
• 1d (1 day)
• 1w (1 week)

🖼️ Output Formats

• PNG: High-quality raster format
• JPEG: Compressed raster format

📖 Full Documentation

For complete usage guide with detailed examples, see USAGE.md 📚

🛠️ Development

📦 Installation

git clone https://github.com/NeaByteLab/Chart-To-Image.git
cd Chart-To-Image
npm install

🔨 Build

npm run build

🚀 Development Mode

npm run dev

🧪 Testing

npm test

🔍 Linting

npm run lint
npm run lint:fix

📁 Project Structure

src/
├── core/
│   ├── config.ts         # Chart configuration
│   └── renderer.ts       # Chart rendering engine
├── renderer/
│   ├── charts.ts         # Chart type renderers
│   ├── elements.ts       # Chart elements (axes, grid, etc.)
│   ├── index.ts          # Main renderer orchestrator
│   ├── types.ts          # Renderer types
│   └── utils.ts          # Renderer utilities
├── types/
│   └── types.ts          # TypeScript type definitions
├── utils/
│   ├── cli.ts            # CLI argument parsing
│   ├── exporter.ts       # Image export utilities
│   ├── provider.ts       # Market data fetching
│   └── utils.ts          # Chart data utilities
├── index.ts              # Main API exports
└── cli.ts                # Command line interface

🤝 Contributing

1. 🍴 Fork the repository
2. 🌿 Create a feature branch
3. ✏️ Make your changes
4. 🧪 Add tests if applicable
5. 📤 Submit a pull request

📄 License

MIT License - see LICENSE file for details.