A ComfyUI custom node for reading color profiles and color space information from image files. This node extracts ICC profiles, PNG color space chunks, and other color metadata to help you understand the color characteristics of your images.

🎨 Features

Color Profile Detection

ICC Profile Extraction: Reads embedded ICC color profiles from images
PNG Color Space Support: Extracts sRGB, gamma, and chromaticity data from PNG files
Multi-format Support: Works with JPEG, PNG, TIFF, WEBP, and other formats supported by Pillow
Profile Analysis: Provides detailed information about color profiles and color spaces

Gamma Comparison

Gamma Analysis: Compares gamma values between two images
Standard Gamma Detection: Identifies common gamma values (sRGB, Rec. 709, Rec. 2020, etc.)
Tolerance-based Comparison: Configurable tolerance for gamma difference detection
Detailed Recommendations: Provides workflow and technical recommendations for gamma mismatches

Output Information

Profile JSON: Complete color profile metadata in JSON format
ICC Base64: Raw ICC profile data encoded in Base64
Primaries JSON: Color primaries and white point information
Notes JSON: Any warnings or additional information about the image

🚀 Installation

Method 1: ComfyUI Manager (Recommended)

Open ComfyUI
Go to Manager → Install
Search for "ComfyUI Color Profile Reader"
Click Install

Method 2: Manual Installation

Clone this repository to your ComfyUI custom_nodes directory:

cd ComfyUI/custom_nodes
git clone https://github.com/yourusername/ComfyUI-color-tools.git

Install dependencies:

cd ComfyUI-color-tools
pip install -r requirements.txt

Restart ComfyUI to load the new node

📖 Usage

Basic Color Profile Reading

Add a "Color Profile Reader" node from the "Image/Color" category
Connect an image path (string) to the image_path input
The node will output:
- profile_json: Complete profile information
- icc_base64: Raw ICC profile data
- primaries_json: Color primaries information
- notes_json: Any additional notes or warnings

OCIO Configuration Usage

The OCIO nodes work with both built-in configurations and custom files:

Official OCIO Configurations

Download OCIO configurations from the Academy Software Foundation ACES config repo:
- Main repository: https://github.com/AcademySoftwareFoundation/OpenColorIO-Config-ACES/tree/main
- Download releases: https://github.com/AcademySoftwareFoundation/OpenColorIO-Config-ACES/releases
- Extract the .ocio file to your desired location (e.g., within your project folder or system config directory)
For the ACES config, recommended locations:
- C:\ProgramData\OpenColorIO\config.ocio (Windows)
- /usr/local/share/OpenColorIO/config.ocio (Linux/Mac)
- Or any path you can easily reference for your project
In the OCIO Color Space Converter node, enter the full path to your .ocio file in the ocio_config_path input

Example Usage

OCIO Config Path: C:\ProgramData\OpenColorIO\config.ocio
Source Color Space: sRGB
Target Color Space: ACEScg

If no config path is specified, the nodes use OCIO's default built-in configuration.

Getting OCIO Config Info

Use the OCIO Config Info node to see what color spaces are available in your configuration and understand the structure.

Workflow Integration

The node outputs JSON strings that can be:

Displayed in Text nodes for inspection
Used with Conditional nodes for branching logic
Processed by other nodes that accept string inputs
Saved to files for further analysis

🛠️ Node Details

📊 Color Profile Nodes

Color Profile Reader

What it does: Extracts color profile and color space information from image files. Reads ICC profiles, PNG color space chunks, and other color metadata to understand the color characteristics of your images.

Inputs:

image_path (STRING): Path to the image file (absolute or relative to ComfyUI)

Outputs:

profile_json (STRING): Complete color profile metadata
icc_base64 (STRING): Raw ICC profile data in Base64 encoding
primaries_json (STRING): Color primaries and white point data
notes_json (STRING): Additional information and warnings

Gamma Compare

What it does: Compares gamma values between two images and provides detailed analysis. Detects gamma mismatches that could affect color accuracy and provides recommendations for color management.

Inputs:

image_path_1 (STRING): Path to the first image file
image_path_2 (STRING): Path to the second image file
tolerance (FLOAT): Tolerance for gamma difference detection (0.001-0.1)

Outputs:

comparison_json (STRING): Detailed comparison data between the two images
gamma_analysis (STRING): In-depth gamma analysis and interpretation
recommendations (STRING): Workflow and technical recommendations

Color Profile → sRGB / Linear

What it does: Converts images to sRGB or linear sRGB using ICC profiles, PNG color space data, or chromaticity matrices. Provides professional-grade color space conversion with fallback handling.

Inputs:

image (IMAGE): Input image tensor
target_space (COMBO): "sRGB" or "sRGB_linear"
icc_profile_base64 (STRING): ICC profile data from ColorProfileReader
png_srgb_intent (INT): PNG sRGB rendering intent (-1 to 3)
png_gamma (FLOAT): PNG gamma value
png_chromaticity_json (STRING): PNG chromaticity data from ColorProfileReader

Outputs:

image (IMAGE): Converted image in target color space

🔄 Color Conversion Nodes

Color Space Converter

What it does: Converts images between different color spaces including RGB, HSV, HSL, LAB, XYZ, and CMYK. Supports gamma correction and preserves alpha channels.

Inputs:

image (IMAGE): Input image
source_space (COMBO): Source color space
target_space (COMBO): Target color space
preserve_alpha (BOOLEAN): Whether to preserve alpha channel
gamma_correction (FLOAT): Gamma correction value

Outputs:

image (IMAGE): Converted image
conversion_info (STRING): Conversion details

Color Temperature

What it does: Adjusts color temperature and tint of images. Simulates warm/cool lighting conditions and provides fine control over color balance.

Inputs:

image (IMAGE): Input image
temperature (FLOAT): Temperature adjustment (-100 to 100)
tint (FLOAT): Tint adjustment (-100 to 100)

Outputs:

image (IMAGE): Temperature-adjusted image

Color Space Analyzer

What it does: Analyzes color space properties and provides detailed information about image characteristics. Generates recommendations for color management.

Inputs:

image (IMAGE): Input image

Outputs:

color_space_info (STRING): Color space information
color_stats (STRING): Color statistics
recommendations (STRING): Color management recommendations

🎨 Color Grading Nodes

Color Balance

What it does: Adjusts color balance for shadows, midtones, and highlights separately. Provides professional color correction capabilities similar to video editing software.

Inputs:

image (IMAGE): Input image
shadow_red/green/blue (FLOAT): Shadow color adjustments
midtone_red/green/blue (FLOAT): Midtone color adjustments
highlight_red/green/blue (FLOAT): Highlight color adjustments

Outputs:

image (IMAGE): Color-balanced image

Brightness/Contrast

What it does: Adjusts brightness and contrast of images. Provides precise control over exposure and contrast levels.

Inputs:

image (IMAGE): Input image
brightness (FLOAT): Brightness adjustment (-1.0 to 1.0)
contrast (FLOAT): Contrast adjustment (0.0 to 3.0)

Outputs:

image (IMAGE): Adjusted image

Saturation

What it does: Adjusts color saturation while optionally preserving luminance. Can boost or reduce color intensity.

Inputs:

image (IMAGE): Input image
saturation (FLOAT): Saturation multiplier (0.0 to 3.0)
preserve_luminance (BOOLEAN): Whether to preserve luminance

Outputs:

image (IMAGE): Saturation-adjusted image

Hue Shift

What it does: Shifts hue values of images. Useful for color correction and creative color effects.

Inputs:

image (IMAGE): Input image
hue_shift (FLOAT): Hue shift in degrees (-180 to 180)

Outputs:

image (IMAGE): Hue-shifted image

Gamma Correction

What it does: Applies gamma correction to images. Essential for proper color management and display calibration.

Inputs:

image (IMAGE): Input image
gamma (FLOAT): Gamma value (0.1 to 5.0)

Outputs:

image (IMAGE): Gamma-corrected image

📈 Color Analysis Nodes

Dominant Colors

What it does: Extracts dominant colors from images using K-means clustering. Useful for color palette generation and color scheme analysis.

Inputs:

image (IMAGE): Input image
num_colors (INT): Number of colors to extract (1-20)
color_format (COMBO): Output format (RGB, HSV, HEX)

Outputs:

dominant_colors (STRING): Extracted colors as JSON
color_percentages (STRING): Color percentages as JSON

Color Histogram

What it does: Generates color histograms for analysis. Provides detailed color distribution information across different color spaces.

Inputs:

image (IMAGE): Input image
bins (INT): Number of histogram bins (32-512)
histogram_type (COMBO): Color space for histogram (RGB, HSV, LAB)

Outputs:

histogram_data (STRING): Histogram data as JSON
statistics (STRING): Color statistics as JSON

Color Palette

What it does: Generates comprehensive color palettes from images using various quantization methods. Creates color schemes for design workflows.

Inputs:

image (IMAGE): Input image
palette_size (INT): Number of colors in palette (3-32)
palette_type (COMBO): Quantization method (K-means, Median Cut, Octree)

Outputs:

palette (STRING): Color palette as JSON
palette_info (STRING): Palette information as JSON

Color Similarity

What it does: Finds colors similar to a target color based on color distance. Useful for color matching and replacement workflows.

Inputs:

image (IMAGE): Input image
target_color (STRING): Target color (hex or RGB)
similarity_threshold (FLOAT): Similarity threshold (0.0-1.0)
color_space (COMBO): Color space for comparison (RGB, HSV, LAB)

Outputs:

mask (IMAGE): Similarity mask
similarity_info (STRING): Similarity analysis as JSON

Color Harmony

What it does: Analyzes color harmony and relationships in images. Evaluates complementary, triadic, analogous, and other color harmony types.

Inputs:

image (IMAGE): Input image
harmony_type (COMBO): Type of harmony to analyze

Outputs:

harmony_analysis (STRING): Harmony analysis as JSON
color_relationships (STRING): Color relationships as JSON

🔧 Advanced Tools Nodes

Color Matcher

What it does: Matches and replaces colors in images. Supports exact, similar, and hue-only matching modes for color correction workflows.

Inputs:

image (IMAGE): Input image
source_color (STRING): Color to match
target_color (STRING): Replacement color
tolerance (FLOAT): Matching tolerance (0.0-1.0)
replace_mode (COMBO): Replacement mode (Exact, Similar, Hue Only)

Outputs:

image (IMAGE): Color-matched image
replacement_info (STRING): Replacement statistics as JSON

Color Quantizer

What it does: Reduces the number of colors in images using various quantization methods. Useful for creating indexed color images and artistic effects.

Inputs:

image (IMAGE): Input image
num_colors (INT): Target number of colors (2-256)
quantization_method (COMBO): Quantization method (K-means, Median Cut, Octree, Uniform)
dithering (BOOLEAN): Whether to apply dithering

Outputs:

image (IMAGE): Quantized image
quantization_info (STRING): Quantization statistics as JSON

Gamut Mapper

What it does: Maps colors between different color gamuts. Essential for color management when working with different display technologies.

Inputs:

image (IMAGE): Input image
source_gamut (COMBO): Source color gamut
target_gamut (COMBO): Target color gamut
mapping_method (COMBO): Gamut mapping method (Perceptual, Relative, Saturation, Absolute)

Outputs:

image (IMAGE): Gamut-mapped image
mapping_info (STRING): Mapping information as JSON

Color Blind Simulator

What it does: Simulates different types of color blindness. Useful for accessibility testing and understanding how color-blind users perceive images.

Inputs:

image (IMAGE): Input image
color_blindness_type (COMBO): Type of color blindness to simulate
severity (FLOAT): Simulation severity (0.0-1.0)

Outputs:

image (IMAGE): Simulated image
simulation_info (STRING): Simulation details as JSON

☹️ OCIO Nodes

OCIO Color Space Converter

What it does: Professional color space conversions using OpenColorIO configurations. Supports industry-standard color pipelines and professional color management.

Inputs:

image (IMAGE): Input image tensor
ocio_config_path (STRING): Path to .ocio configuration file (optional)
source_colorspace (STRING): Source color space name
target_colorspace (STRING): Target color space name

Outputs:

image (IMAGE): Converted image in target color space
conversion_info (STRING): Conversion details and metadata

OCIO Config Info

What it does: Displays information about OCIO configurations, including available color spaces, displays, and viewing transforms.

Inputs:

ocio_config_path (STRING): Path to .ocio configuration file (optional)

Outputs:

config_info (STRING): Detailed configuration information

Test Pattern Generator

What it does: Generates test patterns for color space validation and calibration. Creates color bars, tone ramps, SMPTE color bars, and ColorChecker-like patterns essential for testing OCIO transforms.

Inputs:

pattern_type (COMBO): Type of test pattern (Color Bars, Tone Ramp, Gray Ramp, SMPTE Color Bars, ColorChecker)
width (INT): Pattern width in pixels
height (INT): Pattern height in pixels

Outputs:

test_pattern (IMAGE): Generated test pattern image
pattern_info (STRING): Description of the generated pattern

Recommended workflow: Generate test patterns, convert them through OCIO color spaces, and visually compare results to validate color accuracy.

Profile JSON Structure

{
  "container": "PNG",
  "pillow_mode": "RGB",
  "icc_present": true,
  "icc_profile_name": "sRGB IEC61966-2.1",
  "icc_summary": {
    "profile_class": "mntr",
    "pcs": "XYZ ",
    "acsp_sanity": true
  },
  "srgb_chunk_intent": 0,
  "gamma": 0.45455,
  "chromaticity": {
    "wx": 0.3127,
    "wy": 0.3290,
    "rx": 0.64,
    "ry": 0.33,
    "gx": 0.30,
    "gy": 0.60,
    "bx": 0.15,
    "by": 0.06
  }
}

📊 Use Cases

Color Management Workflows

Verify color profiles in source images
Ensure proper color space handling in processing pipelines
Detect color profile mismatches that could affect output quality
Compare gamma values between images for consistency

Image Analysis

Analyze color characteristics of reference images
Extract color space information for documentation
Validate color profile compliance
Detect gamma mismatches that could cause color shifts

Quality Control

Check for missing or incorrect color profiles
Verify color space consistency across image sets
Monitor color profile usage in production workflows
Ensure gamma consistency in multi-image projects

Gamma Comparison Workflows

Compare gamma values between source and output images
Detect gamma mismatches in color pipelines
Analyze gamma characteristics for color space identification
Generate recommendations for gamma correction

🔧 Dependencies

Pillow>=8.0.0: Image processing and ICC profile support
opencolorio>=2.0.0: Professional color management (OCIO nodes)

📁 Project Structure

ComfyUI-color-tools/
├── README.md
├── LICENSE
├── requirements.txt
├── pyproject.toml
├── __init__.py
├── nodes/
│   ├── __init__.py
│   ├── advanced_tools.py
│   ├── color_analysis.py
│   ├── color_conversion.py
│   ├── color_converter_advanced.py
│   ├── color_grading.py
│   ├── color_profile_convert.py
│   ├── color_profile_convert_simple.py
│   ├── color_profile_reader.py
│   └── ocio_tools.py  (OpenColorIO integration)
└── examples/
    └── color_profile_workflow.json

🤝 Contributing

Fork the repository
Create a feature branch
Make your changes
Add tests for new functionality
Submit a pull request

📄 License

MIT License - See LICENSE file for details.

🆘 Support

For issues, feature requests, or questions:

Open an issue on GitHub
Check the documentation
Review example workflows

🔄 Version History

v1.0.0: Initial release with color profile reading functionality

🙏 Acknowledgments

ComfyUI community for the excellent framework
Pillow team for image processing capabilities
ICC profile specification contributors

Author: Pablo Apiolazza
Repository: ComfyUI-color-tools
Category: Image/Color