1. What is the Hue Angle?

The Hue Angle is a measurement used in color science and image processing to represent the color attribute in various color spaces. It is calculated from the a and b components in color models like CIELAB, representing the angle in the color plane.

2. How Does the Calculator Work?

The calculator uses the Hue Angle formula:

Where:

• \( a \) — a color component
• \( b \) — b color component
• \( \arctan2 \) — Two-argument arctangent function
• \( \pi \) — Mathematical constant pi (≈3.14159)

Explanation: The function calculates the angle between the positive a-axis and the point (a, b) in the color plane, returning the result in degrees.

3. Importance of Hue Angle Calculation

Details: Hue angle calculation is essential in color analysis, digital imaging, quality control in manufacturing, and scientific research where precise color measurement and classification are required.

4. Using the Calculator

Tips: Enter the a and b component values. The calculator will compute the hue angle in degrees (0-360° range). Both values can be positive, negative, or zero.

5. Frequently Asked Questions (FAQ)

Q1: What color spaces use hue angle?
A: Hue angle is commonly used in CIELAB, CIELCh, and other polar color spaces where it represents the actual color tone.

Q2: What is the range of hue angle values?
A: Hue angle typically ranges from 0° to 360°, representing the full color circle from red through yellow, green, blue, and back to red.

Q3: How is atan2 different from regular arctan?
A: atan2 takes two arguments (y, x) and returns the angle in the correct quadrant, handling cases where x is zero and providing a full 360° range.

Q4: Can both a and b components be zero?
A: If both a and b are zero, the hue angle is undefined as it represents a neutral (achromatic) point without color tone.

Q5: What applications use hue angle calculations?
A: Color matching, image processing, quality control in printing/textiles, food industry color grading, and scientific color measurement.