public void WuQuantizerCanCreateFrameQuantizer()
{
var quantizer = new WuQuantizer();
IQuantizer <Rgba32> frameQuantizer = quantizer.CreatePixelSpecificQuantizer <Rgba32>(Configuration.Default);
Assert.NotNull(frameQuantizer);
Assert.NotNull(frameQuantizer.Options);
Assert.Equal(QuantizerConstants.DefaultDither, frameQuantizer.Options.Dither);
frameQuantizer.Dispose();
quantizer = new WuQuantizer(new QuantizerOptions {
Dither = null
});
frameQuantizer = quantizer.CreatePixelSpecificQuantizer <Rgba32>(Configuration.Default);
Assert.NotNull(frameQuantizer);
Assert.Null(frameQuantizer.Options.Dither);
frameQuantizer.Dispose();
quantizer = new WuQuantizer(new QuantizerOptions {
Dither = KnownDitherings.Atkinson
});
frameQuantizer = quantizer.CreatePixelSpecificQuantizer <Rgba32>(Configuration.Default);
Assert.NotNull(frameQuantizer);
Assert.Equal(KnownDitherings.Atkinson, frameQuantizer.Options.Dither);
frameQuantizer.Dispose();
}
public void QuantizersDitherByDefault()
{
var werner = new WernerPaletteQuantizer();
var webSafe = new WebSafePaletteQuantizer();
var octree = new OctreeQuantizer();
var wu = new WuQuantizer();
Assert.NotNull(werner.Options.Dither);
Assert.NotNull(webSafe.Options.Dither);
Assert.NotNull(octree.Options.Dither);
Assert.NotNull(wu.Options.Dither);
using (IQuantizer <Rgba32> quantizer = werner.CreatePixelSpecificQuantizer <Rgba32>(this.Configuration))
{
Assert.NotNull(quantizer.Options.Dither);
}
using (IQuantizer <Rgba32> quantizer = webSafe.CreatePixelSpecificQuantizer <Rgba32>(this.Configuration))
{
Assert.NotNull(quantizer.Options.Dither);
}
using (IQuantizer <Rgba32> quantizer = octree.CreatePixelSpecificQuantizer <Rgba32>(this.Configuration))
{
Assert.NotNull(quantizer.Options.Dither);
}
using (IQuantizer <Rgba32> quantizer = wu.CreatePixelSpecificQuantizer <Rgba32>(this.Configuration))
{
Assert.NotNull(quantizer.Options.Dither);
}
}
// 이미지를 팔레트화시킨다.
// 팔레트에는 반드시 검은색과 흰색은 빠지도록 한다.
static string ExecuteQuantize(string sourceFileName, int maxColor = 30)
{
Logger.WriteLine($"Running {nameof(ExecuteQuantize)}");
var targetFileName = AppendToFileName(sourceFileName, "-Q");
var quOpts = new QuantizerOptions {
MaxColors = maxColor
};
//var quantizer = new OctreeQuantizer(quOpts);
var quantizer = new WuQuantizer(quOpts);
var config = Configuration.Default;
var pixelQuantizer = quantizer.CreatePixelSpecificQuantizer <Rgba32>(config);
using (var image = Image.Load <Rgba32>(sourceFileName))
using (var quantizedResult =
pixelQuantizer.BuildPaletteAndQuantizeFrame(image.Frames[0], image.Frames[0].Bounds()))
{
var quantizedPalette = new List <Color>();
foreach (var p in quantizedResult.Palette.Span)
{
var c = new Color(p);
// 팔레트에 흰색과 검은색은 반드시 빠지도록 한다.
if (c != Color.White && c != Color.Black)
{
quantizedPalette.Add(c);
}
}
using (var stream = new FileStream(targetFileName, FileMode.Create))
{
var encoder = new PngEncoder
{
Quantizer = new PaletteQuantizer(quantizedPalette.ToArray()),
ColorType = PngColorType.Palette
};
image.SaveAsPng(stream, encoder);
stream.Close();
}
return(targetFileName);
}
}
public static ImageColors ProcessImage(Stream imageStream, string filename)
{
var image = Image.Load <Rgba32>(imageStream);
try {
if (image.Width > 800 || image.Height > 800)
{
image.Mutate(i => i.Resize(800, 800));
}
var imageFrame = image.Frames[0];
var quantizer = new WuQuantizer(new QuantizerOptions {
MaxColors = 12
});
var frameQuantizer = quantizer.CreatePixelSpecificQuantizer <Rgba32>(Configuration.Default);
frameQuantizer.BuildPaletteAndQuantizeFrame(imageFrame, image.Bounds());
var quantizedColors = frameQuantizer.QuantizeFrame(imageFrame, image.Bounds());
var paletteColors = quantizedColors.Palette;
var frame = image.Frames[0];
var totalPixels = frame.Width * frame.Height;
frame.TryGetSinglePixelSpan(out var pixels);
var counter = new double[paletteColors.Length];
foreach (var pixel in pixels)
{
var closestDistance = double.MaxValue;
var nearestColorIndex = -1;
for (var index = 0; index < paletteColors.Length; index++)
{
var paletteColor = paletteColors.Span[index];
var distance = EuclideanDistance(paletteColor, pixel);
if (distance < closestDistance)
{
closestDistance = distance;
nearestColorIndex = index;
}
}
counter[nearestColorIndex]++;
}
var colors = paletteColors.Span.ToArray().Select((color, idx) => {
var(hue, saturation, value) = ColorToHsv(color);
return(new ExtractedColor {
Hsv = new HsvColor(hue, saturation, value),
Hex = color.ToHex().Substring(0, 6),
Fraction = counter[idx] / totalPixels
});
});
return(new ImageColors {
Filename = filename,
Colors = colors.OrderByDescending(c => c.Fraction).ToList()
});
} finally {
image?.Dispose();
}
}