invert function
Invert the colors of the src
image.
Implementation
Image invert(Image src) {
final p = src.getBytes();
for (var i = 0, len = p.length; i < len; i += 4) {
p[i] = 255 - p[i];
p[i + 1] = 255 - p[i + 1];
p[i + 2] = 255 - p[i + 2];
}
return src;
}