private static ColorMoment Bottom(Box cube, int direction, ColorMoment[, , ,] moment)
{
switch (direction)
{
case Alpha:
return (-moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum]) -
(-moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
case Red:
return (-moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum]) -
(-moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
case Green:
return (-moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum]) -
(-moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
case Blue:
return (-moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]) -
(-moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
default:
return new ColorMoment();
}
}
private static ColorMoment Volume(Box cube, ColorMoment[, , ,] moment)
{
return (moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] -
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum]) -
(moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] -
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
}
private static CubeCut Maximize(ColorMoment[, , ,] moments, Box cube, int direction, byte first, byte last, ColorMoment whole)
{
var bottom = Bottom(cube, direction, moments);
var result = 0.0f;
byte? cutPoint = null;
for (var position = first; position < last; ++position)
{
var half = bottom + Top(cube, direction, position, moments);
if (half.Weight == 0) continue;
var temp = half.WeightedDistance();
half = whole - half;
if (half.Weight != 0)
{
temp += half.WeightedDistance();
if (temp > result)
{
result = temp;
cutPoint = position;
}
}
}
return new CubeCut(cutPoint, result);
}
private static Box[] SplitData(ref int colorCount, int maxColors, ColorMoment[, , ,] moments)
{
--colorCount;
var next = 0;
var volumeVariance = new float[maxColors];
var cubes = new Box[maxColors];
cubes[0].AlphaMaximum = MaxSideIndex;
cubes[0].RedMaximum = MaxSideIndex;
cubes[0].GreenMaximum = MaxSideIndex;
cubes[0].BlueMaximum = MaxSideIndex;
for (var cubeIndex = 1; cubeIndex < colorCount; ++cubeIndex)
{
if (Cut(moments, ref cubes[next], ref cubes[cubeIndex]))
{
volumeVariance[next] = cubes[next].Size > 1 ? CalculateVariance(moments, cubes[next]) : 0.0f;
volumeVariance[cubeIndex] = cubes[cubeIndex].Size > 1 ? CalculateVariance(moments, cubes[cubeIndex]) : 0.0f;
}
else
{
volumeVariance[next] = 0.0f;
cubeIndex--;
}
next = 0;
var temp = volumeVariance[0];
for (var index = 1; index <= cubeIndex; ++index)
{
if (volumeVariance[index] <= temp) continue;
temp = volumeVariance[index];
next = index;
}
if (temp > 0.0) continue;
colorCount = cubeIndex + 1;
break;
}
return cubes.Take(colorCount).ToArray();
}
private static float CalculateVariance(ColorMoment[, , ,] moments, Box cube)
{
ColorMoment volume = Volume(cube, moments);
return volume.Variance();
}
private static bool Cut(ColorMoment[, , ,] moments, ref Box first, ref Box second)
{
int direction;
var whole = Volume(first, moments);
var maxAlpha = Maximize(moments, first, Alpha, (byte)(first.AlphaMinimum + 1), first.AlphaMaximum, whole);
var maxRed = Maximize(moments, first, Red, (byte)(first.RedMinimum + 1), first.RedMaximum, whole);
var maxGreen = Maximize(moments, first, Green, (byte)(first.GreenMinimum + 1), first.GreenMaximum, whole);
var maxBlue = Maximize(moments, first, Blue, (byte)(first.BlueMinimum + 1), first.BlueMaximum, whole);
if ((maxAlpha.Value >= maxRed.Value) && (maxAlpha.Value >= maxGreen.Value) && (maxAlpha.Value >= maxBlue.Value))
{
direction = Alpha;
if (!maxAlpha.Position.HasValue) return false;
}
else if ((maxRed.Value >= maxAlpha.Value) && (maxRed.Value >= maxGreen.Value) && (maxRed.Value >= maxBlue.Value))
direction = Red;
else
{
if ((maxGreen.Value >= maxAlpha.Value) && (maxGreen.Value >= maxRed.Value) && (maxGreen.Value >= maxBlue.Value))
direction = Green;
else
direction = Blue;
}
second.AlphaMaximum = first.AlphaMaximum;
second.RedMaximum = first.RedMaximum;
second.GreenMaximum = first.GreenMaximum;
second.BlueMaximum = first.BlueMaximum;
switch (direction)
{
case Alpha:
second.AlphaMinimum = first.AlphaMaximum = maxAlpha.Position.Value;
second.RedMinimum = first.RedMinimum;
second.GreenMinimum = first.GreenMinimum;
second.BlueMinimum = first.BlueMinimum;
break;
case Red:
second.RedMinimum = first.RedMaximum = maxRed.Position.Value;
second.AlphaMinimum = first.AlphaMinimum;
second.GreenMinimum = first.GreenMinimum;
second.BlueMinimum = first.BlueMinimum;
break;
case Green:
second.GreenMinimum = first.GreenMaximum = maxGreen.Position.Value;
second.AlphaMinimum = first.AlphaMinimum;
second.RedMinimum = first.RedMinimum;
second.BlueMinimum = first.BlueMinimum;
break;
case Blue:
second.BlueMinimum = first.BlueMaximum = maxBlue.Position.Value;
second.AlphaMinimum = first.AlphaMinimum;
second.RedMinimum = first.RedMinimum;
second.GreenMinimum = first.GreenMinimum;
break;
}
first.Size = (first.AlphaMaximum - first.AlphaMinimum) * (first.RedMaximum - first.RedMinimum) * (first.GreenMaximum - first.GreenMinimum) * (first.BlueMaximum - first.BlueMinimum);
second.Size = (second.AlphaMaximum - second.AlphaMinimum) * (second.RedMaximum - second.RedMinimum) * (second.GreenMaximum - second.GreenMinimum) * (second.BlueMaximum - second.BlueMinimum);
return true;
}
private static float VolumeFloat(Box cube, float[,,,] moment)
{
return (moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] -
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum]) -
(moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] -
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
}
private static Pixel[] BuildLookups(Box[] cubes, ColorMoment[, , ,] moments)
{
Pixel[] lookups = new Pixel[cubes.Length];
for (int cubeIndex = 0; cubeIndex < cubes.Length; cubeIndex++)
{
var volume = Volume(cubes[cubeIndex], moments);
if (volume.Weight <= 0) continue;
var lookup = new Pixel
{
Alpha = (byte)(volume.Alpha / volume.Weight),
Red = (byte)(volume.Red / volume.Weight),
Green = (byte)(volume.Green / volume.Weight),
Blue = (byte)(volume.Blue / volume.Weight)
};
lookups[cubeIndex] = lookup;
}
return lookups;
}
private static long Top(Box cube, int direction, int position, long[,,,] moment)
{
switch (direction)
{
case Alpha:
return (moment[position, cube.RedMaximum, cube.GreenMaximum, cube.BlueMaximum] -
moment[position, cube.RedMaximum, cube.GreenMinimum, cube.BlueMaximum] -
moment[position, cube.RedMinimum, cube.GreenMaximum, cube.BlueMaximum] +
moment[position, cube.RedMinimum, cube.GreenMinimum, cube.BlueMaximum]) -
(moment[position, cube.RedMaximum, cube.GreenMaximum, cube.BlueMinimum] -
moment[position, cube.RedMaximum, cube.GreenMinimum, cube.BlueMinimum] -
moment[position, cube.RedMinimum, cube.GreenMaximum, cube.BlueMinimum] +
moment[position, cube.RedMinimum, cube.GreenMinimum, cube.BlueMinimum]);
case Red:
return (moment[cube.AlphaMaximum, position, cube.GreenMaximum, cube.BlueMaximum] -
moment[cube.AlphaMaximum, position, cube.GreenMinimum, cube.BlueMaximum] -
moment[cube.AlphaMinimum, position, cube.GreenMaximum, cube.BlueMaximum] +
moment[cube.AlphaMinimum, position, cube.GreenMinimum, cube.BlueMaximum]) -
(moment[cube.AlphaMaximum, position, cube.GreenMaximum, cube.BlueMinimum] -
moment[cube.AlphaMaximum, position, cube.GreenMinimum, cube.BlueMinimum] -
moment[cube.AlphaMinimum, position, cube.GreenMaximum, cube.BlueMinimum] +
moment[cube.AlphaMinimum, position, cube.GreenMinimum, cube.BlueMinimum]);
case Green:
return (moment[cube.AlphaMaximum, cube.RedMaximum, position, cube.BlueMaximum] -
moment[cube.AlphaMaximum, cube.RedMinimum, position, cube.BlueMaximum] -
moment[cube.AlphaMinimum, cube.RedMaximum, position, cube.BlueMaximum] +
moment[cube.AlphaMinimum, cube.RedMinimum, position, cube.BlueMaximum]) -
(moment[cube.AlphaMaximum, cube.RedMaximum, position, cube.BlueMinimum] -
moment[cube.AlphaMaximum, cube.RedMinimum, position, cube.BlueMinimum] -
moment[cube.AlphaMinimum, cube.RedMaximum, position, cube.BlueMinimum] +
moment[cube.AlphaMinimum, cube.RedMinimum, position, cube.BlueMinimum]);
case Blue:
return (moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMaximum, position] -
moment[cube.AlphaMaximum, cube.RedMaximum, cube.GreenMinimum, position] -
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMaximum, position] +
moment[cube.AlphaMaximum, cube.RedMinimum, cube.GreenMinimum, position]) -
(moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMaximum, position] -
moment[cube.AlphaMinimum, cube.RedMaximum, cube.GreenMinimum, position] -
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMaximum, position] +
moment[cube.AlphaMinimum, cube.RedMinimum, cube.GreenMinimum, position]);
default:
return 0;
}
}
private static IList<Box> SplitData(ref int colorCount, ColorData data)
{
--colorCount;
var next = 0;
var volumeVariance = new float[MaxColor];
var cubes = new Box[MaxColor];
cubes[0].AlphaMaximum = MaxSideIndex;
cubes[0].RedMaximum = MaxSideIndex;
cubes[0].GreenMaximum = MaxSideIndex;
cubes[0].BlueMaximum = MaxSideIndex;
for (var cubeIndex = 1; cubeIndex < colorCount; ++cubeIndex)
{
if (Cut(data, ref cubes[next], ref cubes[cubeIndex]))
{
volumeVariance[next] = cubes[next].Size > 1 ? CalculateVariance(data, cubes[next]) : 0.0f;
volumeVariance[cubeIndex] = cubes[cubeIndex].Size > 1 ? CalculateVariance(data, cubes[cubeIndex]) : 0.0f;
}
else
{
volumeVariance[next] = 0.0f;
cubeIndex--;
}
next = 0;
var temp = volumeVariance[0];
for (var index = 1; index <= cubeIndex; ++index)
{
if (volumeVariance[index] <= temp) continue;
temp = volumeVariance[index];
next = index;
}
if (temp > 0.0) continue;
colorCount = cubeIndex + 1;
break;
}
return cubes.Take(colorCount).ToList();
}
private static CubeCut Maximize(ColorData data, Box cube, int direction, byte first, byte last, long wholeAlpha, long wholeRed, long wholeGreen, long wholeBlue, long wholeWeight)
{
var bottomAlpha = Bottom(cube, direction, data.MomentsAlpha);
var bottomRed = Bottom(cube, direction, data.MomentsRed);
var bottomGreen = Bottom(cube, direction, data.MomentsGreen);
var bottomBlue = Bottom(cube, direction, data.MomentsBlue);
var bottomWeight = Bottom(cube, direction, data.Weights);
var result = 0.0f;
byte? cutPoint = null;
for (var position = first; position < last; ++position)
{
var halfAlpha = bottomAlpha + Top(cube, direction, position, data.MomentsAlpha);
var halfRed = bottomRed + Top(cube, direction, position, data.MomentsRed);
var halfGreen = bottomGreen + Top(cube, direction, position, data.MomentsGreen);
var halfBlue = bottomBlue + Top(cube, direction, position, data.MomentsBlue);
var halfWeight = bottomWeight + Top(cube, direction, position, data.Weights);
if (halfWeight == 0) continue;
var halfDistance = halfAlpha * halfAlpha + halfRed * halfRed + halfGreen * halfGreen + halfBlue * halfBlue;
var temp = halfDistance / halfWeight;
halfAlpha = wholeAlpha - halfAlpha;
halfRed = wholeRed - halfRed;
halfGreen = wholeGreen - halfGreen;
halfBlue = wholeBlue - halfBlue;
halfWeight = wholeWeight - halfWeight;
if (halfWeight != 0)
{
halfDistance = halfAlpha * halfAlpha + halfRed * halfRed + halfGreen * halfGreen + halfBlue * halfBlue;
temp += halfDistance / halfWeight;
if (temp > result)
{
result = temp;
cutPoint = position;
}
}
}
return new CubeCut(cutPoint, result);
}
private static bool Cut(ColorData data, ref Box first,ref Box second)
{
int direction;
var wholeAlpha = Volume(first, data.MomentsAlpha);
var wholeRed = Volume(first, data.MomentsRed);
var wholeGreen = Volume(first, data.MomentsGreen);
var wholeBlue = Volume(first, data.MomentsBlue);
var wholeWeight = Volume(first, data.Weights);
var maxAlpha = Maximize(data, first, Alpha, (byte) (first.AlphaMinimum + 1), first.AlphaMaximum, wholeAlpha, wholeRed, wholeGreen, wholeBlue, wholeWeight);
var maxRed = Maximize(data, first, Red, (byte) (first.RedMinimum + 1), first.RedMaximum, wholeAlpha, wholeRed, wholeGreen, wholeBlue, wholeWeight);
var maxGreen = Maximize(data, first, Green, (byte) (first.GreenMinimum + 1), first.GreenMaximum, wholeAlpha, wholeRed, wholeGreen, wholeBlue, wholeWeight);
var maxBlue = Maximize(data, first, Blue, (byte) (first.BlueMinimum + 1), first.BlueMaximum, wholeAlpha, wholeRed, wholeGreen, wholeBlue, wholeWeight);
if ((maxAlpha.Value >= maxRed.Value) && (maxAlpha.Value >= maxGreen.Value) && (maxAlpha.Value >= maxBlue.Value))
{
direction = Alpha;
if (maxAlpha.Position == null) return false;
}
else if ((maxRed.Value >= maxAlpha.Value) && (maxRed.Value >= maxGreen.Value) && (maxRed.Value >= maxBlue.Value))
direction = Red;
else
{
if ((maxGreen.Value >= maxAlpha.Value) && (maxGreen.Value >= maxRed.Value) && (maxGreen.Value >= maxBlue.Value))
direction = Green;
else
direction = Blue;
}
second.AlphaMaximum = first.AlphaMaximum;
second.RedMaximum = first.RedMaximum;
second.GreenMaximum = first.GreenMaximum;
second.BlueMaximum = first.BlueMaximum;
switch (direction)
{
case Alpha:
second.AlphaMinimum = first.AlphaMaximum = (byte) maxAlpha.Position;
second.RedMinimum = first.RedMinimum;
second.GreenMinimum = first.GreenMinimum;
second.BlueMinimum = first.BlueMinimum;
break;
case Red:
second.RedMinimum = first.RedMaximum = (byte) maxRed.Position;
second.AlphaMinimum = first.AlphaMinimum;
second.GreenMinimum = first.GreenMinimum;
second.BlueMinimum = first.BlueMinimum;
break;
case Green:
second.GreenMinimum = first.GreenMaximum = (byte) maxGreen.Position;
second.AlphaMinimum = first.AlphaMinimum;
second.RedMinimum = first.RedMinimum;
second.BlueMinimum = first.BlueMinimum;
break;
case Blue:
second.BlueMinimum = first.BlueMaximum = (byte) maxBlue.Position;
second.AlphaMinimum = first.AlphaMinimum;
second.RedMinimum = first.RedMinimum;
second.GreenMinimum = first.GreenMinimum;
break;
}
first.Size = (first.AlphaMaximum - first.AlphaMinimum) * (first.RedMaximum - first.RedMinimum) * (first.GreenMaximum - first.GreenMinimum) * (first.BlueMaximum - first.BlueMinimum);
second.Size = (second.AlphaMaximum - second.AlphaMinimum) * (second.RedMaximum - second.RedMinimum) * (second.GreenMaximum - second.GreenMinimum) * (second.BlueMaximum - second.BlueMinimum);
return true;
}
private static float CalculateVariance(ColorData data, Box cube)
{
float volumeAlpha = Volume(cube, data.MomentsAlpha);
float volumeRed = Volume(cube, data.MomentsRed);
float volumeGreen = Volume(cube, data.MomentsGreen);
float volumeBlue = Volume(cube, data.MomentsBlue);
float volumeMoment = VolumeFloat(cube, data.Moments);
float volumeWeight = Volume(cube, data.Weights);
float distance = volumeAlpha * volumeAlpha + volumeRed * volumeRed + volumeGreen * volumeGreen + volumeBlue * volumeBlue;
var result = volumeMoment - distance / volumeWeight;
return result.ToString() == "NaN" ? 0.0f : result;
}