Original PickImageColors source-file lab, 2026-10-25.
Why can a gray color report a hue of zero?
Run: python reproduce.py --case gray-hue-zero --out rerun
Dependency: Pillow. Recorded runtime: Python 3.12.14, Pillow 12.3.0, libwebp 1.6.0.
Measurements are local source-file computations, not browser observations. Library-dependent compression sizes and quantizer choices may change with runtime.
We measured Python colorsys, not every color-picker interface. A program can represent an achromatic hue differently. This experiment also does not measure perceived warmth, display calibration or color-name matching.
