brightness function Null safety

Image? brightness(
  1. Image? src,
  2. int brightness
)

Set the brightness level for the image src. brightness is an offset that is added to the red, green, and blue channels of every pixel.

Implementation

Image? brightness(Image? src, int brightness) {
  if (src == null || brightness == 0) {
    return src;
  }

  final pixels = src.getBytes();
  for (var i = 0, len = pixels.length; i < len; i += 4) {
    pixels[i] = clamp255(pixels[i] + brightness);
    pixels[i + 1] = clamp255(pixels[i + 1] + brightness);
    pixels[i + 2] = clamp255(pixels[i + 2] + brightness);
  }

  return src;
}