github/greenshot
1
0
Fork 0
mirror of https://github.com/greenshot/greenshot synced 2025-08-20 13:33:27 -07:00
Code Issues Projects Releases Packages Wiki Activity Actions

Performance improvements for the Wu quantizer.

Browse source 
git-svn-id: http://svn.code.sf.net/p/greenshot/code/trunk@1717 7dccd23d-a4a3-4e1f-8c07-b4c1b4018ab4
This commit is contained in:
RKrom 2012-03-21 11:44:13 +00:00
commit 4a5e04ae23
3 changed files with 276 additions and 390 deletions
Download patch file Download diff file Expand all files Collapse all files

51
GreenshotPlugin/Core/ImageHelper.cs
View file

@ -1005,56 +1005,5 @@ namespace GreenshotPlugin.Core {
returnBitmap.RotateFlip(rotateFlipType);
return returnBitmap;
}
/// <summary>
/// Get a quantizer, so we can check if it pays off to quantize
/// </summary>
/// <param name="sourceBitmap"></param>
/// <returns>IColorQuantizer</returns>
public static IColorQuantizer PrepareQuantize(Bitmap sourceBitmap) {
IColorQuantizer quantizer = new WuColorQuantizer();
quantizer.Prepare(sourceBitmap);
using (BitmapBuffer bbbSrc = new BitmapBuffer(sourceBitmap, false)) {
bbbSrc.Lock();
for (int y = 0; y < bbbSrc.Height; y++) {
for (int x = 0; x < bbbSrc.Width; x++) {
quantizer.AddColor(bbbSrc.GetColorAt(x, y));
}
}
}
return quantizer;
}
/// <summary>
/// Quantize the sourceBitmap with the Quantizer returned by PrepareQuantize
/// </summary>
/// <param name="sourceBitmap"></param>
/// <param name="quantizer"></param>
/// <returns>Quantized bitmap</returns>
public static Bitmap Quantize(Bitmap sourceBitmap, IColorQuantizer quantizer, int paletteSize) {
Bitmap result = new Bitmap(sourceBitmap.Width, sourceBitmap.Height, PixelFormat.Format8bppIndexed);
List<Color> palette = quantizer.GetPalette(paletteSize);
ColorPalette imagePalette = result.Palette;
// copies all color entries
for (Int32 index = 0; index < palette.Count; index++) {
imagePalette.Entries[index] = palette[index];
}
result.Palette = imagePalette;
using (BitmapBuffer bbbDest = new BitmapBuffer(result, false)) {
bbbDest.Lock();
using (BitmapBuffer bbbSrc = new BitmapBuffer(sourceBitmap, false)) {
bbbSrc.Lock();
for (int y = 0; y < bbbSrc.Height; y++) {
for (int x = 0; x < bbbSrc.Width; x++) {
Color originalColor = bbbSrc.GetColorAt(x, y);
Int32 paletteIndex = quantizer.GetPaletteIndex(originalColor);
bbbDest.SetColorIndexAt(x,y, (byte)paletteIndex);
}
}
}
}
return result;
}
}
}