Gamma

Gamma (Brightness Transfer Function)

Gamma describes the nonlinear relationship between pixel values and displayed brightness. A gamma of 2.2 (the sRGB standard) means that pixel value 128 is not 50% brightness but approximately 21.8%, matching human perception.

Техническая деталь

The gamma function is expressed as output = input^gamma. sRGB uses a piecewise function: linear below 0.0031308, then ((1.055 * value^(1/2.4)) - 0.055) above. Gamma correction ensures linear light values map to perceptually uniform steps.

Пример

```javascript
// Convert RGB to HSL
function rgbToHsl(r, g, b) {
  r /= 255; g /= 255; b /= 255;
  const max = Math.max(r, g, b), min = Math.min(r, g, b);
  const l = (max + min) / 2;
  let h = 0, s = 0;
  if (max !== min) {
    const d = max - min;
    s = l > 0.5 ? d/(2-max-min) : d/(max+min);
  }
  return [h, s, l];
}
```

Связанные инструменты

Связанные термины

Alpha Channel Bit Depth Chroma Subsampling AVIF Alpha Compositing Batch Resize Aspect Ratio Canvas