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Merged
meesoft merged 10 commits into from
Apr 17, 2026
Merged

Optimize bitmap operations #78

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cef4680
Optimize bitmap operations
meesoft Apr 5, 2026
8f4822b
Optimize ToPixels8
meesoft Apr 5, 2026
07d1250
ArrayPool in LanczosResizeOperation
meesoft Apr 5, 2026
15b0eb3
Optimize LanczosResizeOperation
meesoft Apr 6, 2026
33997d4
Revert unrolling
meesoft Apr 8, 2026
3ad7470
Max op test
meesoft Apr 10, 2026
6c38910
Optimize ColorToneAdjustOperation
meesoft Apr 10, 2026
d011ae4
size
meesoft Apr 15, 2026
09be5b4
Return after use
meesoft Apr 17, 2026
fe8c91b
Cleanup
meesoft Apr 17, 2026
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23 changes: 12 additions & 11 deletions PhotoLocator/BitmapOperations/ColorToneAdjustOperation.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -104,9 +104,9 @@ public static void ColorTransformHSI2RGB(float h, float s, float i, out float r,

public static void ColorTransformRGB2HSI(float r, float g, float b, out float h, out float s, out float i)
{
r = RealMath.Clamp(r, 0f, 1f);
g = RealMath.Clamp(g, 0f, 1f);
b = RealMath.Clamp(b, 0f, 1f);
r = Math.Clamp(r, 0f, 1f);
g = Math.Clamp(g, 0f, 1f);
b = Math.Clamp(b, 0f, 1f);
i = (r + g + b) / 3f;
if (i == 0)
{
Expand All @@ -115,17 +115,17 @@ public static void ColorTransformRGB2HSI(float r, float g, float b, out float h,
}
else
{
var D = r;
if (g < D)
D = g;
if (b < D)
D = b;
s = Math.Max(0, 1 - 3f / (r + g + b) * D);
var min = r;
if (g < min)
min = g;
if (b < min)
min = b;
s = Math.Max(0, 1 - 3f / (r + g + b) * min);
if (s == 0)
h = 0;
else
{
var a = 0.5 * (r - g + (r - b)) / Math.Sqrt(RealMath.Sqr(r - g) + (r - b) * (g - b));
var a = 0.5 * (r - g + (r - b)) / Math.Sqrt((r - g) * (r - g) + (r - b) * (g - b));
double rh;
if (a <= -1)
rh = Math.PI;
Expand Down Expand Up @@ -177,13 +177,14 @@ public override void Apply()
Parallel.For(0, _srcHSI.Height, y =>
{
var toneAdjustments = ToneAdjustments;
var width = _srcHSI.Width;
unsafe
{
fixed (float* src = &_srcHSI.Elements[y, 0])
fixed (float* dst = &DstBitmap.Elements[y, 0])
{
int xx = 0;
for (var x = 0; x < _srcHSI.Width; x++)
for (var x = 0; x < width; x++)
{
var tone = (src[xx] - Rotation) * NumberOfTones;
if (tone < 0)
Expand Down
99 changes: 64 additions & 35 deletions PhotoLocator/BitmapOperations/FloatBitmap.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -84,12 +84,12 @@ public void Assign(BitmapSource source, double gamma)
Parallel.For(0, Height, y =>
{
fixed (float* gamma = gammaLut)
fixed (float* elements = &Elements[y, 0])
fixed (ushort* sourceRow = &sourcePixels[y * Stride])
fixed (float* dstRow = &Elements[y, 0])
fixed (ushort* srcRow = &sourcePixels[y * Stride])
{
var stride = Stride;
for (var x = 0; x < stride; x++)
elements[x] = gamma[sourceRow[x]];
dstRow[x] = gamma[srcRow[x]];
}
});
}
Expand All @@ -106,14 +106,15 @@ public void Assign(BitmapSource source, double gamma)
Parallel.For(0, Height, y =>
{
fixed (float* gamma = gammaLut)
fixed (float* elements = &Elements[y, 0])
fixed (byte* sourceRow = &sourcePixels[y * Stride])
fixed (float* dstRow = &Elements[y, 0])
fixed (byte* srcRow = &sourcePixels[y * Stride])
{
for (var x = 0; x < Width; x++)
var width = Width;
for (var x = 0; x < width; x++)
{
elements[x * 3 + 2] = gamma[sourceRow[x * 3 + 0]];
elements[x * 3 + 1] = gamma[sourceRow[x * 3 + 1]];
elements[x * 3 + 0] = gamma[sourceRow[x * 3 + 2]];
dstRow[x * 3 + 2] = gamma[srcRow[x * 3 + 0]];
dstRow[x * 3 + 1] = gamma[srcRow[x * 3 + 1]];
dstRow[x * 3 + 0] = gamma[srcRow[x * 3 + 2]];
}
}
});
Expand All @@ -133,14 +134,15 @@ public void Assign(BitmapSource source, double gamma)
Parallel.For(0, Height, y =>
{
fixed (float* gamma = gammaLut)
fixed (float* elements = &Elements[y, 0])
fixed (byte* sourceRow = &sourcePixels[y * Width * 4])
fixed (float* dstRow = &Elements[y, 0])
fixed (byte* srcRow = &sourcePixels[y * Width * 4])
{
for (var x = 0; x < Width; x++)
var width = Width;
for (var x = 0; x < width; x++)
{
elements[x * 3 + 2] = gamma[sourceRow[x * 4 + 0]];
elements[x * 3 + 1] = gamma[sourceRow[x * 4 + 1]];
elements[x * 3 + 0] = gamma[sourceRow[x * 4 + 2]];
dstRow[x * 3 + 2] = gamma[srcRow[x * 4 + 0]];
dstRow[x * 3 + 1] = gamma[srcRow[x * 4 + 1]];
dstRow[x * 3 + 0] = gamma[srcRow[x * 4 + 2]];
}
}
});
Expand Down Expand Up @@ -168,12 +170,12 @@ public void Assign(BitmapSource source, double gamma)
Parallel.For(0, Height, y =>
{
fixed (float* gamma = gammaLut)
fixed (float* elements = &Elements[y, 0])
fixed (byte* sourceRow = &sourcePixels[y * Stride])
fixed (float* dstRow = &Elements[y, 0])
fixed (byte* srcRow = &sourcePixels[y * Stride])
{
var stride = Stride;
for (var x = 0; x < stride; x++)
elements[x] = gamma[sourceRow[x]];
dstRow[x] = gamma[srcRow[x]];
}
});
}
Expand All @@ -192,7 +194,8 @@ public void Assign(BitmapPlaneInt16 src, Func<short, float> remap)
fixed (Int16* srcPix = &src.Elements[y, 0])
fixed (float* dstPix = &Elements[y, 0])
{
for (int x = 0; x < Width; x++)
var width = Width;
for (int x = 0; x < width; x++)
dstPix[x] = remap(srcPix[x]);
}
});
Expand All @@ -214,8 +217,8 @@ public BitmapSource ToBitmapSource(double dpiX, double dpiY, double gamma, Pixel
return (bitmap, Task.Run(() =>
{
var histogram = new int[256];
var length = Height * Stride;
for (int i = 0; i < length; i++)
var size = Size;
for (int i = 0; i < size; i++)
histogram[pixels[i]]++;
ArrayPool<byte>.Shared.Return(pixels);
return histogram;
Expand All @@ -228,17 +231,19 @@ private byte[] ToPixels8(double gamma)
var gammaLut = CreateGammaLookupFloatToByte(gamma);
unsafe
{
//gamma = 1 / gamma;
Parallel.For(0, Height, y =>
{
var stride = Stride;
fixed (byte* gamma = gammaLut)
fixed (float* elements = &Elements[y, 0])
fixed (byte* destRow = &pixels[y * Stride])
fixed (float* srcRow = &Elements[y, 0])
fixed (byte* dstRow = &pixels[y * stride])
{
var stride = Stride;
for (var x = 0; x < stride; x++)
//destRow[x] = (byte)IntMath.Clamp((int)(Math.Pow(elements[x], gamma) * 255 + 0.5), 0, 255);
destRow[x] = gamma[IntMath.Clamp((int)(elements[x] * FloatToByteGammaLutRange + 0.5f), 0, FloatToByteGammaLutRange)];
{
int idx = (int)(srcRow[x] * FloatToByteGammaLutRange + 0.5f);
if (idx < 0) idx = 0; else if (idx > FloatToByteGammaLutRange) idx = FloatToByteGammaLutRange;
dstRow[x] = gamma[idx];
}
}
});
}
Expand Down Expand Up @@ -266,7 +271,7 @@ public void SaveToFile(string fileName, double gamma = 1)
GeneralFileFormatHandler.SaveToFile(ToBitmapSource(96, 96, gamma), fileName);
}

static float[] CreateDeGammaLookup(double gamma, int range)
internal static float[] CreateDeGammaLookup(double gamma, int range)
{
var gammaLUT = ArrayPool<float>.Shared.Rent(range);
var scale = 1.0 / (range - 1);
Expand Down Expand Up @@ -374,12 +379,28 @@ public float Min()
{
fixed (float* elements = Elements)
{
var size = Size;
for (var i = 0; i < size; i++)
var p = elements;
// Process in blocks of 8 to reduce loop overhead and branch misprediction
var remaining = Size;
while (remaining >= 8)
{
var v0 = p[0]; if (v0 < min) min = v0; if (v0 > max) max = v0;
var v1 = p[1]; if (v1 < min) min = v1; if (v1 > max) max = v1;
var v2 = p[2]; if (v2 < min) min = v2; if (v2 > max) max = v2;
var v3 = p[3]; if (v3 < min) min = v3; if (v3 > max) max = v3;
var v4 = p[4]; if (v4 < min) min = v4; if (v4 > max) max = v4;
var v5 = p[5]; if (v5 < min) min = v5; if (v5 > max) max = v5;
var v6 = p[6]; if (v6 < min) min = v6; if (v6 > max) max = v6;
var v7 = p[7]; if (v7 < min) min = v7; if (v7 > max) max = v7;
p += 8;
remaining -= 8;
}
// Finish remaining elements
for (var i = 0; i < remaining; i++)
{
var value = elements[i];
min = Math.Min(min, value);
max = Math.Max(max, value);
var value = *p++;
if (value < min) min = value;
if (value > max) max = value;
}
}
}
Expand All @@ -394,8 +415,16 @@ public double Mean()
{
fixed (float* elements = Elements)
{
for (var i = 0; i < size; i++)
sum += elements[i];
float* p = elements;
var remaining = size;
while (remaining >= 8)
{
sum += p[0] + p[1] + p[2] + p[3] + p[4] + p[5] + p[6] + p[7];
p += 8;
remaining -= 8;
}
for (var i = 0; i < remaining; i++)
sum += *p++;
}
}
return sum / size;
Expand Down
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