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wip dither tweaks

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This commit is contained in:
Brooke Vibber 2022-12-04 15:03:36 -08:00
parent ece161d6d6
commit e460fcefb0
1 changed files with 19 additions and 19 deletions
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38
dither-image.js
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@ -78,14 +78,18 @@ class RGB {
return this;
}
add(other) {
static add(a, b) {
return new RGB(
this.r + other.r,
this.g + other.g,
this.b + other.b
a.r + b.r,
a.g + b.g,
a.b + b.b
);
}
add(other) {
return RGB.add(this, other);
}
difference(other) {
return new RGB(
this.r - other.r,
@ -407,10 +411,11 @@ function decimate(input, palette, n, inputError) {
let dither = (palette) => {
let fitness = new Float64Array(width);
let error = {
right: new RGB(0, 0, 0),
cur: [],
next: [],
};
for (let i = 0; i < width; i++) {
error.cur[i] = new RGB(0, 0, 0);
error.next[i] = new RGB(0, 0, 0);
}
@ -421,8 +426,7 @@ function decimate(input, palette, n, inputError) {
// Try dithering with this palette.
for (let x = 0; x < width; x++) {
let rgb = input[x];
rgb = rgb.add(error.right);
let rgb = RGB.add(input[x], error.cur[x]);
if (inputError) {
rgb.inc(inputError[x]);
}
@ -445,18 +449,14 @@ function decimate(input, palette, n, inputError) {
output[x] = pick;
popularity[pick]++;
if (x == width - 1) {
let half = nextError.divide(4);
error.next[x - 1].inc(half);
error.next[x].inc(half);
// drop half the error on the floor at the edge ;_;
} else {
let quarter = nextError.divide(4);
error.right = quarter;
error.next[x - 1]?.inc(quarter); // @fixme should we change the amount?
error.next[x].inc(quarter);
error.next[x + 1].inc(quarter);
}
let shares = 8;
let single = nextError.divide(shares);
let double = nextError.divide(shares / 2);
error.cur[x + 1]?.inc(double);
error.cur[x + 2]?.inc(single);
error.next[x - 1]?.inc(double);
error.next[x]?.inc(double);
error.next[x + 1]?.inc(single);
// 442 is the 3d distance across the rgb cube
//fitness[x] = 442 - (nextError.magnitude());