pub fn dither(
image: &Image,
settings: OneBitSettings,
) -> Result<Vec<u8>, String>Expand description
The one-bit picture file of image made by settings: one style the
image’s size, and a mask if a pixel is see-through. Its source size is
the image’s own. An error, in plain words, for a picture too big for
the file (a side over 65,535 pixels), with no pixels or short of them,
or for one with a grey under Dither::None.