Color Management on Embedded Systems Development

Gamma Correction

Mon, 01 Jan 0001 00:00:00 +0000

Gamma Correction#

Human vision perceives brightness logarithmically, but LEDs emit light linearly with PWM duty cycle. Without gamma correction, a fade from 0 to 255 looks like it jumps to “almost full brightness” in the first quarter and then barely changes for the remaining three-quarters. Applying a gamma curve transforms linear PWM values into perceptually uniform brightness steps — making a value of 128 actually look like “half brightness” to the eye.

HSV & Color Spaces

Mon, 01 Jan 0001 00:00:00 +0000

HSV & Color Spaces#

RGB is the native language of addressable LEDs — each pixel takes a red, green, and blue value — but it’s a terrible color space for humans to think in. Asking “what RGB values make a slightly warmer orange at half brightness?” is unintuitive. HSV (Hue, Saturation, Value) separates color identity from brightness and saturation, making it the natural choice for LED animation and color design. Understanding the mapping between color spaces — and the tradeoffs of each — is fundamental to producing predictable LED output.

White Balance & Color Temperature

Mon, 01 Jan 0001 00:00:00 +0000

White Balance & Color Temperature#

Driving an RGB LED at (255, 255, 255) rarely produces what the eye perceives as “white.” Most WS2812B strips produce a distinctly cool, bluish white because the blue die is typically the most efficient and the green-to-red phosphor balance varies by manufacturer. Achieving a consistent, pleasing white — or matching a specific color temperature — requires per-channel scaling that compensates for the LED’s spectral characteristics.