public static UIImage Filter(UIImage img, int puzzleSize)
{
int tileSize = 2;
int paletteColorsNumber = BasePaletteColorsNumber + (8 * puzzleSize / 64);
// 1/ Get the main colors
// So we have a color palette
Logger.I("Filter: getting palette...");
var colorPalette = getColorPalette(img, paletteColorsNumber);
// 1/ Resize & Load image as readable
UIImage resizedImg = UIImageEx.ResizeRatio(img, puzzleSize);
Bitmap bitmap = new Bitmap(resizedImg);
// 2/ Apply mosaic
Logger.I("Filter: applying mosaic...");
var flippedImage = applyMosaic(tileSize, colorPalette, resizedImg, bitmap);
// -- Flip because bitmap has inverted coordinates
Logger.I("Filter: resizing...");
UIImage finalImg = new UIImage(flippedImage, 0f, UIImageOrientation.DownMirrored);
// UIImage finalImg = new UIImage (flippedImage);
// -- Resize the final
// return ResizeRatio (finalImg, FinalSize);
Logger.I("Filter: image ready!");
return(finalImg);
}
private static List <Color> getColorPalette(UIImage img, int paletteColorsNumber)
{
// -- Make a thumbnail for better performace
Logger.D("Palette -> resize");
UIImage thumb = UIImageEx.ResizeRatio(img, Math.Min(96, (int)Math.Max(img.Size.Width, img.Size.Height)));
Bitmap thumbBitmap = new Bitmap(thumb);
// -- Get each colors
Logger.D("Palette -> get each color");
Dictionary <Color, int> rawColorList = new Dictionary <Color, int> ();
for (int xq = 0; xq < thumb.Size.Width; xq++)
{
for (int yq = 0; yq < thumb.Size.Height; yq++)
{
Color c = thumbBitmap.GetPixel(xq, yq);
if (rawColorList.ContainsKey(c))
{
rawColorList [c] += 1;
}
else
{
rawColorList.Add(c, 1);
}
} // for y
} // for x
var orderedColorList = rawColorList
.Where(c => c.Value > 1) // Take only colors that appear at least twice (huge optim)
.OrderByDescending(c => c.Value) // Order by frequency
.Select(c => c.Key) // Select only keys
.ToList();
// -- Look if we have a similar color already in the palette
Logger.D("Palette -> restrict to n");
List <Color> colorPalette = new List <Color> (paletteColorsNumber);
while (colorPalette.Count < paletteColorsNumber)
{
if (orderedColorList.Any() == false)
{
Logger.W("Palette -> Not enough color!");
break;
}
Color c1 = orderedColorList.First();
List <Color> similarColors = new List <Color> ();
similarColors.Add(c1);
int avg_r = c1.R;
int avg_b = c1.B;
int avg_g = c1.G;
// Look for similar colors
foreach (Color c2 in orderedColorList)
{
if (c1 == c2)
{
continue;
}
double distance = Math.Abs(Math.Pow(c1.R - c2.R, 2) + Math.Pow(c1.G - c2.G, 2) + Math.Pow(c1.B - c2.B, 2));
if (distance < PaletteColorDifferenceThreshold)
{
// Too close, do the average
avg_r += c2.R;
avg_g += c2.G;
avg_b += c2.B;
similarColors.Add(c2);
}
}
// Add the average colors
Color newColor = Color.FromArgb(
avg_r / similarColors.Count,
avg_g / similarColors.Count,
avg_b / similarColors.Count
);
colorPalette.Add(newColor);
// Remove checked colors
foreach (var deletedColor in similarColors)
{
orderedColorList.Remove(deletedColor);
}
}
// Free things
thumbBitmap = null;
return(colorPalette);
}