Switch to nonlinear color difference

This commit is contained in:
Joscha 2024-03-09 23:17:08 +01:00
parent 929ebb84eb
commit 1b8f895680

View file

@ -3,7 +3,7 @@ use image::{
RgbaImage, RgbaImage,
}; };
use mark::dither::{AlgoFloydSteinberg, AlgoStucki, Algorithm, DiffEuclid, Palette}; use mark::dither::{AlgoFloydSteinberg, AlgoStucki, Algorithm, DiffEuclid, Palette};
use palette::{IntoColor, LinSrgb, Srgba}; use palette::{IntoColor, Srgb, Srgba};
use taffy::prelude::{AvailableSpace, Layout, Size}; use taffy::prelude::{AvailableSpace, Layout, Size};
use crate::Widget; use crate::Widget;
@ -15,12 +15,12 @@ pub enum DitherAlgorithm {
} }
impl DitherAlgorithm { impl DitherAlgorithm {
fn dither(self, image: RgbaImage, palette: &Palette<LinSrgb>) -> RgbaImage { fn dither(self, image: RgbaImage, palette: &Palette<Srgb>) -> RgbaImage {
match self { match self {
Self::FloydSteinberg => { Self::FloydSteinberg => {
<AlgoFloydSteinberg as Algorithm<LinSrgb, DiffEuclid>>::run(image, palette) <AlgoFloydSteinberg as Algorithm<Srgb, DiffEuclid>>::run(image, palette)
} }
Self::Stucki => <AlgoStucki as Algorithm<LinSrgb, DiffEuclid>>::run(image, palette), Self::Stucki => <AlgoStucki as Algorithm<Srgb, DiffEuclid>>::run(image, palette),
} }
} }
} }
@ -31,7 +31,11 @@ pub struct Image {
grow: bool, grow: bool,
filter: FilterType, filter: FilterType,
dither_palette: Option<Palette<LinSrgb>>, // The palette uses Srgb instead of LinSrgb because dithering in Srgb
// produces better results when printed, even though color distance
// calculations are objectively wrong. Maybe the printer's black ink
// behaviour makes them correct again.
dither_palette: Option<Palette<Srgb>>,
dither_algorithm: DitherAlgorithm, dither_algorithm: DitherAlgorithm,
} }
@ -66,7 +70,7 @@ impl Image {
let palette = palette let palette = palette
.iter() .iter()
.map(|c| c.color.into_color()) .map(|c| c.color.into_color())
.collect::<Vec<LinSrgb>>(); .collect::<Vec<Srgb>>();
self.dither_palette = Some(Palette::new(palette)); self.dither_palette = Some(Palette::new(palette));
self self