private IndexedImage CreateNewImageWithPalette(IndexedImage sourceImage, Palette palette, IndexedImage destImage)
{
if (destImage == null)
{
destImage = sourceImage.Clone(false);
}
destImage.Size = sourceImage.Size;
destImage.Palette = palette.Clone();
var destPixels = destImage.Pixels;
var searcher = new PaletteQuickColorSearcher(palette);
Parallel.ForEach(sourceImage.Palette,
sourceColor =>
{
Color substColor = searcher.SearchSubstitute(sourceColor);
Debug.Assert(substColor != null, "Substitute color was not found.");
foreach (int occurrence in sourceColor.UsageOccurrences)
{
destPixels[occurrence] = substColor.Argb;
}
});
return(destImage);
}
public void TestSearchSubstiture()
{
var palette = new Palette
{
new Color(0),
new Color(250, 250, 250),
new Color(100, 0, 0),
new Color(0, 100, 0),
new Color(0, 0, 100),
new Color(0, 0, 101)
};
var quickColorSearcher = new PaletteQuickColorSearcher(palette);
using (ColorDistance.UseCoeffs(1, 1, 1))
{
Assert.AreEqual(new Color(0), quickColorSearcher.SearchSubstitute(new Color(0)));
Assert.AreEqual(new Color(250, 250, 250), quickColorSearcher.SearchSubstitute(new Color(254, 254, 254)));
Assert.AreEqual(new Color(0, 0, 100), quickColorSearcher.SearchSubstitute(new Color(98, 98, 99)));
Assert.AreEqual(new Color(0, 100, 0), quickColorSearcher.SearchSubstitute(new Color(98, 99, 98)));
Assert.AreEqual(new Color(100, 0, 0), quickColorSearcher.SearchSubstitute(new Color(99, 98, 98)));
Assert.AreEqual(new Color(0, 0, 100), quickColorSearcher.SearchSubstitute(new Color(0, 0, 99), true));
Assert.AreEqual(new Color(0, 0, 101), quickColorSearcher.SearchSubstitute(new Color(0, 0, 99), true));
}
}
private void UpdateUsagesCounts(Palette palette, IndexedImage sourceImage)
{
foreach (Color color in palette)
{
color.ClearOccurrences();
}
var searcher = new PaletteQuickColorSearcher(palette);
foreach (Color sourceColor in sourceImage.Palette)
{
Color substColor = searcher.SearchSubstitute(sourceColor);
Debug.Assert(substColor != null, "Substitute color was not found.");
substColor.OccurrencesCount += sourceColor.OccurrencesCount;
}
}
public IndexedImage DitherNewImageWithPalette(IndexedImage sourceImage, Palette palette, int ditherLevel, IndexedImage destImage = null)
{
Debug.Assert((ditherLevel >= 1) && (ditherLevel <= MaxDitherLevel), "ditherLevel should is out of range");
if (destImage == null)
{
destImage = sourceImage.Clone(false);
}
destImage.Size = sourceImage.Size;
destImage.Palette = palette.Clone();
var sourcePixels = sourceImage.Pixels;
var destPixels = destImage.Pixels;
const int ErrorCoeff = MaxDitherLevel * MaxDitherLevel * 16;
var tempPixels = new int[sourcePixels.Length, 3];
for (var i = 0; i < sourcePixels.Length; i++)
{
var colorHash = sourcePixels[i];
tempPixels[i, ColorBytes.RedIdx] = colorHash.Red() * ErrorCoeff;
tempPixels[i, ColorBytes.GreenIdx] = colorHash.Green() * ErrorCoeff;
tempPixels[i, ColorBytes.BlueIdx] = colorHash.Blue() * ErrorCoeff;
}
var ditherLevel2 = ditherLevel * ditherLevel;
var ditherCoeffRight = 7 * ditherLevel2;
var ditherCoeffBottomLeft = 3 * ditherLevel2;
var ditherCoeffBottomMiddle = 5 * ditherLevel2;
var ditherCoeffBottomRight = 1 * ditherLevel2;
var searcher = new PaletteQuickColorSearcher(palette);
var sourceWidth = sourceImage.Size.Width;
for (var i = 0; i < sourcePixels.Length; i++)
{
var r = tempPixels[i, ColorBytes.RedIdx] / ErrorCoeff;
if (r < 0)
{
r = 0;
}
if (r > 255)
{
r = 255;
}
var g = tempPixels[i, ColorBytes.GreenIdx] / ErrorCoeff;
if (g < 0)
{
g = 0;
}
if (g > 255)
{
g = 255;
}
var b = tempPixels[i, ColorBytes.BlueIdx] / ErrorCoeff;
if (b < 0)
{
b = 0;
}
if (b > 255)
{
b = 255;
}
var colorSubs = searcher.SearchSubstitute((byte)r, (byte)g, (byte)b);
Debug.Assert(colorSubs != null, "Substitute color was not found.");
destPixels[i] = colorSubs.Argb;
// Populate errors
var colorHash = sourcePixels[i];
var dr = colorHash.Red() - colorSubs.R;
var dg = colorHash.Green() - colorSubs.G;
var db = colorHash.Blue() - colorSubs.B;
var index = i + 1; // right
if ((index < sourcePixels.Length) && ((index % sourceWidth) != 0))
{
tempPixels[index, ColorBytes.RedIdx] += dr * ditherCoeffRight;
tempPixels[index, ColorBytes.GreenIdx] += dg * ditherCoeffRight;
tempPixels[index, ColorBytes.BlueIdx] += db * ditherCoeffRight;
}
index = i + sourceWidth - 1; // bottom left
if ((index < sourcePixels.Length) && ((i % sourceWidth) != 0))
{
tempPixels[index, ColorBytes.RedIdx] += dr * ditherCoeffBottomLeft;
tempPixels[index, ColorBytes.GreenIdx] += dg * ditherCoeffBottomLeft;
tempPixels[index, ColorBytes.BlueIdx] += db * ditherCoeffBottomLeft;
}
index++; // bottom middle
if (index < sourcePixels.Length)
{
tempPixels[index, ColorBytes.RedIdx] += dr * ditherCoeffBottomMiddle;
tempPixels[index, ColorBytes.GreenIdx] += dg * ditherCoeffBottomMiddle;
tempPixels[index, ColorBytes.BlueIdx] += db * ditherCoeffBottomMiddle;
}
index++; // bottom right
if ((index < sourcePixels.Length) && ((index % sourceWidth) != 0))
{
tempPixels[index, ColorBytes.RedIdx] += dr * ditherCoeffBottomRight;
tempPixels[index, ColorBytes.GreenIdx] += dg * ditherCoeffBottomRight;
tempPixels[index, ColorBytes.BlueIdx] += db * ditherCoeffBottomRight;
}
}
return(destImage);
}
