ComfyUIPixelate

sd-webui-pixelart are referenced by many webui users, this node is mean to use it in ComfyUI.

Features

• Downscaling Options: Multiple high-quality scaling algorithms:

  • auto: Automatically selects the best method
  • nearest: Best for preserving exact colors
  • area: Optimal for general downscaling
  • linear: Smooth transitions but may blur
  • cubic: Sharper edges than linear
  • lanczos: High quality with edge preservation

• Color Processing:

  • RGB color mode
  • Grayscale conversion
  • Binary (Black & White) conversion

• Advanced Color Quantization:

  • Multiple palette generation methods:
    • auto: Smart method selection based on image size and color count
    • libimagequant: High-quality quantization
    • kmeans: GPU-accelerated when available (falls back to CPU)
    • mediancut: Fast with good quality
    • maxcoverage: Better color distribution
    • fastoctree: Fastest option for large images
    • median_cut: Custom implementation

• Dithering Support:

  • Floyd-Steinberg dithering for smooth color transitions
  • Simple quantization for clean, sharp results

• Custom Palette Support:

  • Use reference images to extract palettes
  • Control palette size (2-256 colors)

Usage

1. Add the "Pixelate" node to your ComfyUI workflow
2. Connect an image input
3. Configure parameters:
   • downscale_factor: How much to reduce the image (1-32)
   • scale_mode: Choose scaling algorithm
   • rescale_to_original: Option to restore original size
   • color_mode: RGB/Grayscale/BW
   • colors: Number of colors in output (2-256)
   • quantization_method: Palette generation method
   • dithering: None or Floyd-Steinberg
   • Optional: Connect a palette reference image

Performance Considerations

• The node automatically selects optimal methods based on image size:
  • Large images (>1M pixels) or many colors (>32): Uses fast octree
  • Medium images (>500K pixels): Uses libimagequant
  • Small images: Uses k-means clustering
• GPU acceleration for k-means when available
• Caching for color quantization to improve speed

Credits

• Original concept based on sd-webui-pixelart