internal void DrawImage(Bitmap source, int x, int y, int width, int height)
{
var targetFormat = _bitmap.PixelFormat;
List <Color> palette = null;
// indexed formats require 2 passes - one more pass to determines colors for palette beforehand
if (targetFormat.IsIndexed())
{
_quantizer.Prepare(source);
// Pass: scan
ImageBuffer.ProcessPerPixel(source, null, ParallelTaskCount, (passIndex, pixel) =>
{
var color = pixel.GetColor();
_quantizer.AddColor(color, pixel.X, pixel.Y);
return(true);
});
// determines palette
palette = _quantizer.GetPalette(targetFormat.GetColorCount());
}
// Pass: apply
ImageBuffer.TransformImagePerPixel(source, palette, ref _bitmap, null, ParallelTaskCount,
(passIndex, sourcePixel, targetPixel) =>
{
var color = sourcePixel.GetColor();
targetPixel.SetColor(color, _quantizer);
return(true);
});
}
public List <Color> SynthetizePalette(IColorQuantizer quantizer, Int32 colorCount, Int32 parallelTaskCount = 4)
{
// checks parameters
Guard.CheckNull(quantizer, "quantizer");
// Step 1 - prepares quantizer for another round
quantizer.Prepare(this);
// Step 2 - scans the source image for the colors
ScanColors(quantizer, parallelTaskCount);
// Step 3 - synthetises the palette, and returns the result
return(quantizer.GetPalette(colorCount));
}
private void UpdateQuantizer()
{
if (!_pixelFormat.IsIndexed() || _quantizer != null)
{
return;
}
_quantizer = new DistinctSelectionQuantizer();
_quantizer.Prepare(this);
// Pass: scan
ImageBuffer.ProcessPerPixel(this, null, ParallelTaskCount, (passIndex, pixel) =>
{
var color = pixel.GetColor();
_quantizer.AddColor(color, pixel.X, pixel.Y);
return(true);
});
}
private void UpdateQuantizer()
{
if (!_pixelFormat.IsIndexed() || _quantizer != null) return;
_quantizer = new DistinctSelectionQuantizer();
_quantizer.Prepare(this);
// Pass: scan
ImageBuffer.ProcessPerPixel(this, null, ParallelTaskCount, (passIndex, pixel) =>
{
var color = pixel.GetColor();
_quantizer.AddColor(color, pixel.X, pixel.Y);
return true;
});
}
public List<Color> SynthetizePalette(IColorQuantizer quantizer, Int32 colorCount, Int32 parallelTaskCount = 4)
{
// checks parameters
Guard.CheckNull(quantizer, "quantizer");
// Step 1 - prepares quantizer for another round
quantizer.Prepare(this);
// Step 2 - scans the source image for the colors
ScanColors(quantizer, parallelTaskCount);
// Step 3 - synthetises the palette, and returns the result
return quantizer.GetPalette(colorCount);
}
public void Quantize(IColorQuantizer quantizer, int colorCount)
{
if (Disposed)
{
return;
}
int myWidth = Width;
int myHeight = Height;
Color *colors = GetColors();
quantizer.Prepare(this);
bool usesAlpha = false;
// weird stuff to make the quantizer work with alpha
Color lastColor = new Color(255, 255, 255, 0);
bool firstColorFound = false;
for (int y = 0; y < myHeight; y++)
{
for (int x = 0; x < myWidth; x++)
{
int idx = x + y * myWidth;
var col = *(colors + idx);
if (col.A > 128)
{
col.A = 255;
(*(colors + x + y * myWidth)) = col;
if (!firstColorFound && usesAlpha)
{
for (int i = 0; i < idx; i++)
{
quantizer.AddColor(col, i % myWidth, Mathf.FloorToInt(i / myWidth));
}
}
firstColorFound = true;
lastColor = col;
quantizer.AddColor(col, x, y);
}
else
{
col = new Color(255, 255, 255, 0);
(*(colors + x + y * myWidth)) = col;
usesAlpha = true;
if (firstColorFound)
{
quantizer.AddColor(lastColor, x, y);
}
}
}
}
var palette = quantizer.GetPalette(colorCount);
for (int y = 0; y < myHeight; y++)
{
for (int x = 0; x < myWidth; x++)
{
if ((*(colors + x + y * myWidth)).A == 255)
{
int index = quantizer.GetPaletteIndex(*(colors + x + y * myWidth), x, y);
//Debug.Log(index);
*(colors + x + y * myWidth) = palette[index];
}
}
}
quantizer.Finish();
}
/// <summary>
/// Changes the pixel format.
/// </summary>
/// <param name="image">The image.</param>
/// <param name="targetFormat">The target format.</param>
/// <param name="quantizer">The color quantizer.</param>
/// <returns>The converted image in a target format.</returns>
public static Image ChangePixelFormat(this Image image, PixelFormat targetFormat, IColorQuantizer quantizer)
{
// checks for image validity
if (image == null)
{
const String message = "Cannot change a pixel format for a null image.";
throw new ArgumentNullException(message);
}
// checks whether a target format is supported
if (!targetFormat.IsSupported())
{
String message = string.Format("A pixel format '{0}' is not supported.", targetFormat);
throw new NotSupportedException(message);
}
// checks whether there is a quantizer for a indexed format
if (targetFormat.IsIndexed() && quantizer == null)
{
String message = string.Format("A quantizer is cannot be null for indexed pixel format '{0}'.", targetFormat);
throw new NotSupportedException(message);
}
// creates an image with the target format
Bitmap result = new Bitmap(image.Width, image.Height, targetFormat);
ColorPalette imagePalette = image.Palette;
// gathers some information about the target format
Boolean hasSourceAlpha = image.PixelFormat.HasAlpha();
Boolean hasTargetAlpha = targetFormat.HasAlpha();
Boolean isSourceIndexed = image.PixelFormat.IsIndexed();
Boolean isTargetIndexed = targetFormat.IsIndexed();
Boolean isSourceDeepColor = image.PixelFormat.IsDeepColor();
Boolean isTargetDeepColor = targetFormat.IsDeepColor();
// if palette is needed create one first
if (isTargetIndexed)
{
quantizer.Prepare(image);
image.AddColorsToQuantizer(quantizer);
Int32 targetColorCount = result.GetPaletteColorCount();
List<Color> palette = quantizer.GetPalette(targetColorCount);
result.SetPalette(palette);
}
Action<Pixel, Pixel> changeFormat = (sourcePixel, targetPixel) =>
{
// if both source and target formats are deep color formats, copies a value directly
if (isSourceDeepColor && isTargetDeepColor)
{
UInt64 value = sourcePixel.Value;
targetPixel.SetValue(value);
}
else
{
// retrieves a source image color
Color color = isSourceIndexed ? imagePalette.Entries[sourcePixel.Index] : sourcePixel.Color;
// if alpha is not present in the source image, but is present in the target, make one up
if (!hasSourceAlpha && hasTargetAlpha)
{
Int32 argb = 255 << 24 | color.R << 16 | color.G << 8 | color.B;
color = Color.FromArgb(argb);
}
// sets the color to a target pixel
if (isTargetIndexed)
{
// for the indexed images, determines a color from the octree
Byte paletteIndex = (Byte) quantizer.GetPaletteIndex(color);
targetPixel.SetIndex(paletteIndex);
}
else
{
// for the non-indexed images, sets the color directly
targetPixel.SetColor(color);
}
}
};
// process image -> changes format
image.ProcessImagePixels(result, changeFormat);
// returns the image in the target format
return result;
}
