Ishihara Plate Generation — Advanced User Guide (v1.0.0)
Overview
This guide provides a comprehensive overview of the Ishihara Plate Generator available at Color Science Engine — Ishihara Plate Generation. It covers all user-facing features, recommended workflows, parameter explanations, accessibility and ethical considerations, and advanced usage for research and educational purposes. This documentation is intended for educators, researchers, and designers seeking to create custom pseudoisochromatic plates for demonstration, study, or accessibility validation.
1. Introduction
+The Ishihara Plate Generator is a web-based tool for creating custom dot-based color vision test plates. It enables users to generate plates with numbers, letters, symbols, or paths, using scientifically tuned color palettes and advanced algorithms for dot placement and color assignment. The generator is designed for research, education, and accessibility validation, not for clinical diagnosis.
- Supports numbers (0–99), letters (A–Z), symbols, and geometric shapes.
- Multiple color palettes and difficulty levels.
- Color-deficiency simulation (protanopia, deuteranopia, tritanopia).
- High-resolution export for print or digital use.
2. Features & capabilities
+- Interactive Plate Generation: Instantly preview and adjust plates with live rendering.
- Customizable Content: Choose numbers, letters, symbols, or upload custom shapes.
- Advanced Color Palettes: Select from scientifically designed palettes for different color vision scenarios.
- Difficulty Control: Adjust difficulty to control chromatic contrast and luminance similarity.
- Color Vision Simulation: Preview plates as seen by users with common color deficiencies.
- Export Options: Download plates as PNG (web/print).
- Quality Metrics: Automated validation of dot density, color balance, and pattern visibility.
3. Step-by-step workflow
+-
Access the Generator:
Visit the Ishihara Plate Generator in your browser. -
Select Plate Content:
Choose the type (number, letter, symbol, shape, or path) and specify the desired value (e.g., "12", "A", "star"). -
Choose Color Palette:
Select a palette (e.g., Red-Green, Blue-Purple, Sepia) or use "Auto" for random selection. -
Set Difficulty:
Adjust the difficulty slider to control how easily the figure is visible to normal and color-deficient viewers. -
Adjust Parameters:
Optionally set dot count, plate shape (circle/square), and random seed for reproducibility. -
Preview & Simulate:
Use the simulation controls to view the plate as seen by users with protanopia, deuteranopia, or tritanopia. -
Export:
Download the plate as PNG (for web or print). -
Validate:
Review the automated quality metrics and simulation previews to ensure the plate meets your requirements.
4. Parameters & controls
+- Content: Number (0–99), Letter (A–Z), Symbol (star, arrow, etc.), Shape, or Path.
- Palette: Choose from Red-Green, Green-Brown, Blue-Purple, Orange-Green, Teal-Magenta, Yellow-Blue, Sepia, Pastel, or Auto.
- Difficulty: Easy, Medium, Hard, Extreme — controls chromatic and luminance contrast.
- Dot Count: Number of dots (default: 7000). Higher counts yield smoother appearance but require more processing.
- Plate Shape: Circle (classic) or Square.
- Random Seed: Set for reproducible results; leave blank for random generation.
- Export Size: Choose output resolution for PNG export (default: 4096px).
- Simulation Mode: Preview as Normal, Protanopia, Deuteranopia, or Tritanopia.
5. Exporting & printing
+- PNG Export: Suitable for web, presentations, and high-quality printing. Recommended: 300 DPI for print.
- Print Recommendations: Print at native resolution, use high-quality paper, and soft-proof for color accuracy. Always test with your intended printer and viewing conditions.
- Color Management: For professional printing, convert to CMYK using a suitable ICC profile and verify color separations.
6. Accessibility & ethics
+- Plates generated are for educational and research use only; not for clinical diagnosis.
- Label all plates with intended usage, viewing distance, and simulation notes.
- Provide alternative formats or descriptions for users with other visual impairments.
- Do not use generated plates as a substitute for standardized clinical tests.
7. Troubleshooting & FAQ
+- Plate not visible in simulation? Try lowering difficulty or selecting a different palette.
- Exported image appears blurry? Increase export size or check print DPI settings.
- Browser performance issues? Reduce dot count or use a modern browser with hardware acceleration.
- Need reproducible results? Set a specific random seed before generating/exporting.
- Can I use my own shapes? Custom shape upload is planned for future releases; currently, use available symbols and shapes.
8. References
+- Brettel, V., Viénot, F., & Mollon, J. D. (1997). Computerized simulation of color appearance for dichromats. Journal of the Optical Society of America A.
- Oklab color space: Oklab: A perceptual color space for image processing
- Color vision and accessibility resources: W3C, WebAIM, and academic literature.