Enum Dither

#[repr(u8)]
pub enum Dither {
    Auto = 0,
    None = 1,
    Atkinson = 2,
    FS = 3,
    JaJuNi = 4,
    Stucki = 5,
    Burkes = 6,
    ADither = 7,
    XDither = 8,
}

Available on crate feature alloc and crate feature term and (crate features io or std) and (crate features dep_hashbrown or std) and crate feature image only.

Dithering methods of error diffusion.

Dithering helps improve image quality when reducing color depth, commonly used in Sixel, GIF, and other indexed-color formats.

Variants

Auto = 0

Choose diffusion type automatically. (Default)

None = 1

No dithering is applied. Pixels are directly quantized without modification.

Atkinson = 2

Error diffusion dithering using Bill Atkinson’s method.

Produces a softer dithering effect with a limited error spread. Often used in early Macintosh graphics.

FS = 3

Floyd-Steinberg error diffusion dithering.

A widely used method that spreads error to neighboring pixels for smooth gradients. Produces good results with minimal artifacts.

JaJuNi = 4

Jarvis, Judice & Ninke (JaJuNi) error diffusion dithering.

Spreads quantization error further across neighboring pixels, resulting in smoother transitions but requiring more computation.

Stucki = 5

Stucki error diffusion dithering.

Similar to JaJuNi but slightly optimized for faster computation. Produces high-quality results with minimal artifacts.

Burkes = 6

Burkes error diffusion dithering.

A simplified version of Stucki with a smaller diffusion matrix, reducing computation while maintaining good quality.

ADither = 7

Positionally stable arithmetic dithering.

Applies a deterministic arithmetic transformation to each pixel, ensuring consistency without propagating errors.

XDither = 8

Positionally stable XOR-based dithering.

Uses bitwise XOR operations for structured noise generation, creating a high-frequency dithering pattern without error diffusion.

Implementations

impl Dither

pub fn apply_15bpp( self, pixels: &mut [u8], x: i32, y: i32, width: i32, height: i32, )

Applies dithering to a pixel array in 15-bit color mode (5-5-5 RGB).

This method modifies pixel values based on the selected dithering algorithm. It is designed for 15bpp color depth, commonly used in retro graphics and hardware-limited displays.

Behavior

• Error diffusion dithering (e.g., Floyd-Steinberg, Atkinson) is only applied when there is enough space for propagation.
• Positionally stable dithering (e.g., ADither, XDither) is applied unconditionally per pixel.
• None disables dithering, and Auto currently behaves the same.

Trait Implementations

impl Clone for Dither

fn clone(&self) -> Dither

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl ConstDefault for Dither

const DEFAULT: Self = Self::Auto

Returns the compile-time “default value” for a type.

impl Debug for Dither

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Dither

fn default() -> Dither

Returns the “default value” for a type.

impl Hash for Dither

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Dither

fn eq(&self, other: &Dither) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Dither

impl Eq for Dither

impl StructuralPartialEq for Dither