experiments/floyd-steinberg-dithering
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experiments:dithering-algorithm
experiments:pixel-data-structures
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compare: experiments:pixel-data-structures
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experiments:master
experiments:dithering-algorithm
experiments:pixel-data-structures
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21
LICENSE
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@ -1,21 +0,0 @@
MIT License
Copyright (c) 2018 Marty Oehme
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

2
LICENSE.md Normal file
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@ -0,0 +1,2 @@
Copyright (C) 2018

63
lib/Dither.dart
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@ -21,23 +21,16 @@ class Pixed {
PixelArray pxArr = new PixelArray.fromPixelArray(image);
for (var y = 0; y < pxArr.getHeight(); y++) {
for (var x = 0; x < pxArr.getWidth(); x++) {
pxArr.setPixel( _quantizePixel(pxArr.getPixel(x, y)) );
var px = pxArr.getPixel(x, y);
px.r = (steps * px.r / 255).round() * (255 ~/ steps);
px.g = (steps * px.g / 255).round() * (255 ~/ steps);
px.b = (steps * px.b / 255).round() * (255 ~/ steps);
}
}
return pxArr;
}
static Pixel _quantizePixel(Pixel pixel, [int steps=1]) {
return new Pixel(
pixel.x,
pixel.y,
(steps * pixel.r / 255).round() * (255 ~/ steps),
(steps * pixel.g / 255).round() * (255 ~/ steps),
(steps * pixel.b / 255).round() * (255 ~/ steps),
pixel.a);
}
static PixelArray quantizeError(PixelArray original, PixelArray quantized) {
static PixelArray calcQuantizeError(PixelArray original, PixelArray quantized) {
PixelArray pxArr = new PixelArray.fromPixelArray(original);
for (var y = 0; y < pxArr.getHeight(); y++) {
for (var x = 0; x < pxArr.getWidth(); x++) {
@ -50,47 +43,6 @@ class Pixed {
}
return pxArr;
}
static Pixel _quantizeErrorPixel(Pixel original, Pixel quantized) {
return new Pixel(original.x, original.y,
original.r - quantized.r,
original.g - quantized.g,
original.b - quantized.b,
original.a);
}
static PixelArray dither(PixelArray image) {
PixelArray pxArr = new PixelArray.fromPixelArray(image);
for (var y = 0; y < pxArr.getHeight()-1; y++) {
for (var x = 1; x < pxArr.getWidth()-1; x++) {
Pixel origPx = pxArr.getPixel(x, y);
Pixel quantPx = _quantizePixel(origPx);
Pixel errPx = _quantizeErrorPixel(origPx, quantPx);
pxArr.setPixel(quantPx);
Pixel px = pxArr.getPixel(x+1, y);
px.r = (px.r + errPx.r * (7/16)).toInt();
px.g = (px.g + errPx.g * (7/16)).toInt();
px.b = (px.b + errPx.b * (7/16)).toInt();
px = pxArr.getPixel(x-1, y+1);
px.r = (px.r + errPx.r * (3/16)).toInt();
px.g = (px.g + errPx.g * (3/16)).toInt();
px.b = (px.b + errPx.b * (3/16)).toInt();
px = pxArr.getPixel(x, y+1);
px.r = (px.r + errPx.r * (5/16)).toInt();
px.g = (px.g + errPx.g * (5/16)).toInt();
px.b = (px.b + errPx.b * (5/16)).toInt();
px = pxArr.getPixel(x+1, y+1);
px.r = (px.r + errPx.r * (1/16)).toInt();
px.g = (px.g + errPx.g * (1/16)).toInt();
px.b = (px.b + errPx.b * (1/16)).toInt();
}
}
return pxArr;
}
}
class Pixel {
@ -129,7 +81,7 @@ class PixelArray {
pixels = new List(height);
for (int y = 0; y < height; y++) {
pixels[y] = new List(width);
for (int x = 0; x < width; x++) {
for (int x = 0; x < height; x++) {
pixels[y][x] = new Pixel(x, y, 0, 0, 0, 0);
}
}
@ -140,6 +92,7 @@ class PixelArray {
int y = 0;
int x = 0;
pixels[y] = new List(imageWidth);
print(pixels[0].length.toString() + ","+ pixels.length.toString());
for (var pos = 0; pos < array.length; pos = pos + 4) {
if (x >= imageWidth) {
x = 0;
@ -154,7 +107,7 @@ class PixelArray {
PixelArray.fromImageData(ImageData imagedata, int imageWidth): this.fromByteArray(imagedata.data, imageWidth);
PixelArray.fromPixelArray(PixelArray pixelArray) {
pixels = pixelArray.clone().pixels;
pixels = new List<List<Pixel>>.from(pixelArray.pixels);
}
Uint8ClampedList toByteArray() {

4
web/index.html
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@ -14,8 +14,8 @@
</head>
<body>
<canvas id="input"></canvas>
<canvas id="input" width="712" height="470"></canvas>
<canvas id="output"></canvas>
<canvas id="output" width="712" height="470"></canvas>
</body>
</html>

10
web/main.dart
View file

@ -8,15 +8,11 @@ ImageElement inputImg;
ImageElement outputImg;
void main() {
inputImg = new ImageElement(src: 'kitten.jpg');
inputImg = new ImageElement(src: 'kitten.jpg', width: 712, height: 470);
input = document.querySelector('#input');
output = document.querySelector('#output');
input.width = inputImg.width;
input.height = inputImg.height;
output.width = inputImg.width;
output.height = inputImg.height;
inputImg.onLoad.listen(imgLoaded);
}
@ -24,9 +20,9 @@ void imgLoaded(Event e) {
print("image loaded");
input.context2D.drawImage(inputImg, 0, 0);
PixelArray px = new PixelArray.fromImageData(getImageData(input), input.width);
PixelArray px = new PixelArray.fromImageData(getImageData(input), 712);
px = Pixed.greyscale(px);
px = Pixed.dither(px);
output.context2D.putImageData(px.toImageData(), 0, 0);
}