Cat-Printer/www/image.js
NaitLee 500971ae95 Major code clean up; new features:
Test unknown devices (scan everything)
Rework of Web FE Event & Dispatch
Fix major performance problem
Better image processing algorithm
New Halftone-like dither algo., namingly "Pattern"
Some fixes to CSS
Fix potential misc problems by manual testing
2022-07-15 02:51:44 +08:00

126 lines
4.1 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.rotateRgba = exports.monoToPbm = exports.monoHalftone = exports.monoSteinberg = exports.monoDirect = exports.monoToRgba = exports.monoGrayscale = void 0;
function monoGrayscale(rgba, brightness, alpha_as_white) {
let mono = new Uint8ClampedArray(rgba.length);
let r = 0.0, g = 0.0, b = 0.0, a = 0.0, m = 0.0, n = 0;
for (let i = 0; i < mono.length; ++i) {
n = rgba[i];
// little endian
r = (n & 0xff), g = (n >> 8 & 0xff), b = (n >> 16 & 0xff);
a = (n >> 24 & 0xff) / 0xff;
if (a < 1 && alpha_as_white) {
a = 1 - a;
r += (0xff - r) * a;
g += (0xff - g) * a;
b += (0xff - b) * a;
}
else {
r *= a;
g *= a;
b *= a;
}
m = r * 0.2125 + g * 0.7154 + b * 0.0721;
m += (brightness - 0x80) * (1 - m / 0xff) * (m / 0xff) * 2;
mono[i] = m;
}
return mono;
}
exports.monoGrayscale = monoGrayscale;
/** Note: returns a `Uint32Array` */
function monoToRgba(mono) {
let rgba = new Uint32Array(mono.length);
for (let i = 0; i < mono.length; ++i) {
// little endian
rgba[i] = 0xff000000 | (mono[i] << 16) | (mono[i] << 8) | mono[i];
}
return rgba;
}
exports.monoToRgba = monoToRgba;
function monoDirect(mono, w, h) {
for (let i = 0; i < mono.length; ++i) {
mono[i] = mono[i] > 0x80 ? 0xff : 0x00;
}
return mono;
}
exports.monoDirect = monoDirect;
function monoSteinberg(mono, w, h) {
let p = 0, m, n, o;
for (let j = 0; j < h; ++j) {
for (let i = 0; i < w; ++i) {
m = mono[p];
n = mono[p] > 0x80 ? 0xff : 0x00;
o = m - n;
mono[p] = n;
if (i >= 0 && i < w - 1 && j >= 0 && j < h)
mono[p + 1] += (o * 7 / 16);
if (i >= 1 && i < w && j >= 0 && j < h - 1)
mono[p + w - 1] += (o * 3 / 16);
if (i >= 0 && i < w && j >= 0 && j < h - 1)
mono[p + w] += (o * 5 / 16);
if (i >= 0 && i < w - 1 && j >= 0 && j < h - 1)
mono[p + w + 1] += (o * 1 / 16);
++p;
}
}
return mono;
}
exports.monoSteinberg = monoSteinberg;
function monoHalftone(mono, w, h) {
const spot = 4;
const spot_h = spot / 2 + 1;
const spot_d = spot * 2;
const spot_s = spot * spot;
let i, j, x, y, o = 0.0;
for (j = 0; j < h - spot; j += spot) {
for (i = 0; i < w - spot; i += spot) {
for (x = 0; x < spot; ++x)
for (y = 0; y < spot; ++y)
o += mono[(j + y) * w + i + x];
o = (1 - o / spot_s / 0xff) * spot;
for (x = 0; x < spot; ++x)
for (y = 0; y < spot; ++y) {
mono[(j + y) * w + i + x] = Math.abs(x - spot_h) >= o || Math.abs(y - spot_h) >= o ? 0xff : 0x00;
// mono[(j + y) * w + i + x] = Math.abs(x - spot_h) + Math.abs(y - spot_h) >= o ? 0xff : 0x00;
}
}
for (; i < w; ++i)
mono[j * w + i] = 0xff;
}
for (; j < h; ++j)
for (i = 0; i < w; ++i)
mono[j * w + i] = 0xff;
return mono;
}
exports.monoHalftone = monoHalftone;
function monoToPbm(data) {
let length = (data.length / 8) | 0;
let result = new Uint8ClampedArray(length);
for (let i = 0, p = 0; i < data.length; ++p) {
result[p] = 0;
for (let d = 0; d < 8; ++i, ++d)
result[p] |= data[i] & (0b10000000 >> d);
result[p] ^= 0b11111111;
}
return result;
}
exports.monoToPbm = monoToPbm;
/** Note: takes & gives `Uint32Array` */
function rotateRgba(before, w, h) {
/**
* w h
* o------+ +---o
* h | | | | w
* +------+ | | after
* before +---+
*/
let after = new Uint32Array(before.length);
for (let j = 0; j < h; j++) {
for (let i = 0; i < w; i++) {
after[j * w + i] = before[(w - i - 1) * h + j];
}
}
return after;
}
exports.rotateRgba = rotateRgba;