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Merged
meesoft merged 10 commits into from
Sep 26, 2026
Merged

Improve color grading #93

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b4890be
Additional saturation points in tone adjustment
meesoft Aug 23, 2026
9edbb96
Smaller adjustment points
meesoft Sep 19, 2026
02f03c7
Fix hue shift
meesoft Sep 19, 2026
dd51093
Dual tone option
meesoft Sep 19, 2026
3897866
Attach menu item
meesoft Sep 20, 2026
b2ea2b0
Fix reset
meesoft Sep 20, 2026
14f8722
Cleanup
meesoft Sep 20, 2026
31a1ef5
Cartesian hue-map interpolation
meesoft Sep 20, 2026
3211041
Fix setting uniformity
meesoft Sep 21, 2026
7902779
Guard against mode change during processing
meesoft Sep 26, 2026
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223 changes: 200 additions & 23 deletions PhotoLocator/BitmapOperations/ColorToneAdjustOperation.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -6,28 +6,35 @@ namespace PhotoLocator.BitmapOperations
{
class ColorToneAdjustOperation : OperationBase
{
public const int NumberOfTones = 8;
public const int NumberOfHues = 8;

const float SingleToneSaturation = 0.5f;
const float ToneLowSaturation = 0.4f;
const float ToneHighSaturation = 0.9f;

FloatBitmap? _srcHSI;
bool _updateSrcHsi;

public struct ToneAdjustment(float toneHue)
public struct ToneAdjustment(float toneHue, float toneSaturation)
{
public readonly float ToneHue = toneHue;
public float ToneHue { get; } = toneHue;
public float ToneSaturation { get; internal set; } = toneSaturation;
public float AdjustHue = 0;
public float AdjustSaturation = 1;
public float AdjustIntensity = 1;
public float HueUniformity = 0;
}

public int NumberOfTones => ToneAdjustments.Length;

public ToneAdjustment[] ToneAdjustments { get; } = new ToneAdjustment[NumberOfTones];
public ToneAdjustment[] ToneAdjustments { get; private set; } = new ToneAdjustment[NumberOfHues];

public float Rotation
{
get;
set
{
if (value <= -1 || value >= 1)
if (value is <= -1 or >= 1)
throw new ArgumentOutOfRangeException(nameof(value));
field = value;
}
Expand All @@ -37,11 +44,49 @@ public ColorToneAdjustOperation()
{
ResetToneAdjustments();
}

public void ResetToneAdjustments()
{
for (var i = 0; i < NumberOfTones; i++)
ToneAdjustments[i] = new ToneAdjustment((float)i / NumberOfTones);
if (DualToneMode)
for (var i = 0; i < NumberOfHues; i++)
{
ToneAdjustments[i] = new ToneAdjustment((float)i / NumberOfHues, ToneLowSaturation);
ToneAdjustments[i + NumberOfHues] = new ToneAdjustment((float)i / NumberOfHues, ToneHighSaturation);
}
else
for (var i = 0; i < NumberOfHues; i++)
ToneAdjustments[i] = new ToneAdjustment((float)i / NumberOfHues, SingleToneSaturation);
}

public bool DualToneMode
{
get => ToneAdjustments.Length > NumberOfHues;
set
{
if (value != DualToneMode)
{
if (value)
{
var newToneAdjustments = new ToneAdjustment[NumberOfHues * 2];
Array.Copy(ToneAdjustments, newToneAdjustments, NumberOfHues);
Array.Copy(ToneAdjustments, 0, newToneAdjustments, NumberOfHues, NumberOfHues);
for (var i = 0; i < NumberOfHues; i++)
{
newToneAdjustments[i].ToneSaturation = ToneLowSaturation;
newToneAdjustments[i + NumberOfHues].ToneSaturation = ToneHighSaturation;
}
ToneAdjustments = newToneAdjustments;
}
else
{
var newToneAdjustments = new ToneAdjustment[NumberOfHues];
Array.Copy(ToneAdjustments, newToneAdjustments, NumberOfHues);
for (var i = 0; i < NumberOfHues; i++)
newToneAdjustments[i].ToneSaturation = SingleToneSaturation;
ToneAdjustments = newToneAdjustments;
}
}
}
}

public bool AreToneAdjustmentsChanged
Expand Down Expand Up @@ -69,6 +114,8 @@ public static void ColorTransformHSI2RGB(float h, float s, float i, out float r,
h -= 1;
else if (h < 0)
h += 1;
if (s > 1)
s = 1;
double rr, rg, rb, rh;
if (h <= 1f / 3) // 0°<H<=120°
{
Expand Down Expand Up @@ -174,9 +221,18 @@ public override void Apply()
ColorTransformRGB2HSI(SrcBitmap, _srcHSI);
}
DstBitmap.New(_srcHSI.Width, _srcHSI.Height, 3);
Parallel.For(0, _srcHSI.Height, y =>

var toneAdjustments = ToneAdjustments; // Guard against mode change during processing
if (toneAdjustments.Length > NumberOfHues)
ApplyDualToneAdjustments(toneAdjustments);
else
ApplySingleToneAdjustments(toneAdjustments);
}

void ApplySingleToneAdjustments(ToneAdjustment[] toneAdjustments)
{
Parallel.For(0, _srcHSI!.Height, y =>
{
var toneAdjustments = ToneAdjustments;
var width = _srcHSI.Width;
unsafe
{
Expand All @@ -186,14 +242,14 @@ public override void Apply()
int xx = 0;
for (var x = 0; x < width; x++)
{
var tone = (src[xx] - Rotation) * NumberOfTones;
var tone = (src[xx] - Rotation) * NumberOfHues;
if (tone < 0)
tone += NumberOfTones;
if (tone >= NumberOfTones)
tone -= NumberOfTones;
tone += NumberOfHues;
if (tone >= NumberOfHues)
tone -= NumberOfHues;
var toneIndex = (int)tone;
var nextToneIndex = toneIndex + 1;
if (nextToneIndex == NumberOfTones)
if (nextToneIndex == NumberOfHues)
nextToneIndex = 0;
var nextToneWeight = RealMath.SmoothStep(tone - toneIndex);
var toneWeight = 1 - nextToneWeight;
Expand All @@ -218,23 +274,144 @@ public override void Apply()
toneHue * toneHueWeight +
nextToneHue * nextToneHueWeight;
}
var h = hue +
toneAdjustments[toneIndex].AdjustHue * toneWeight +
toneAdjustments[nextToneIndex].AdjustHue * nextToneWeight;
var s = src[xx + 1] *
(toneAdjustments[toneIndex].AdjustSaturation * toneWeight +
toneAdjustments[nextToneIndex].AdjustSaturation * nextToneWeight);
if (s > 1)
s = 1;
var ha = toneAdjustments[toneIndex].AdjustHue;
var haNext = FixHue(toneAdjustments[nextToneIndex].AdjustHue, ha);
double hueVectorX = 0;
double hueVectorY = 0;
AddHueVector(hue + ha, toneAdjustments[toneIndex].AdjustSaturation, toneWeight, ref hueVectorX, ref hueVectorY);
AddHueVector(hue + haNext, toneAdjustments[nextToneIndex].AdjustSaturation, nextToneWeight, ref hueVectorX, ref hueVectorY);
GetHueAndSaturation(hueVectorX, hueVectorY, hue, out var h, out var saturationAdjust);

var s = src[xx + 1] * saturationAdjust;

var i = src[xx + 2] *
(toneAdjustments[toneIndex].AdjustIntensity * toneWeight +
toneAdjustments[nextToneIndex].AdjustIntensity * nextToneWeight);

ColorTransformHSI2RGB(h, s, i, out dst[xx], out dst[xx + 1], out dst[xx + 2]);
xx += 3;
}
}
}
});
}

void ApplyDualToneAdjustments(ToneAdjustment[] toneAdjustments)
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{
Parallel.For(0, _srcHSI!.Height, y =>
{
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 < width; x++)
{
var hueTone = (src[xx] - Rotation) * NumberOfHues;
if (hueTone < 0)
hueTone += NumberOfHues;
if (hueTone >= NumberOfHues)
hueTone -= NumberOfHues;
var hueIndex = (int)hueTone;
var nextHueIndex = hueIndex + 1;
if (nextHueIndex == NumberOfHues)
nextHueIndex = 0;
var nextHueWeight = RealMath.SmoothStep(hueTone - hueIndex);
var hueWeight = 1 - nextHueWeight;

var saturation = src[xx + 1];
float lowSaturationWeight, highSaturationWeight;
if (saturation <= ToneLowSaturation)
{
lowSaturationWeight = 1; highSaturationWeight = 0;
}
else if (saturation >= ToneHighSaturation)
{
lowSaturationWeight = 0; highSaturationWeight = 1;
}
else
{
var saturationTone = (saturation - ToneLowSaturation) / (ToneHighSaturation - ToneLowSaturation);
highSaturationWeight = RealMath.SmoothStep(saturationTone);
lowSaturationWeight = 1 - highSaturationWeight;
}

var hue = src[xx];
if (toneAdjustments[hueIndex].HueUniformity > 0 || toneAdjustments[nextHueIndex].HueUniformity > 0)
{
var toneHue = toneAdjustments[hueIndex].ToneHue + Rotation;
if (toneHue < hue - 0.5f)
toneHue++;
else if (toneHue > hue + 0.5f)
toneHue--;
var nextToneHue = toneAdjustments[nextHueIndex].ToneHue + Rotation;
if (nextToneHue < hue - 0.5f)
nextToneHue++;
else if (nextToneHue > hue + 0.5f)
nextToneHue--;

var toneHueWeight = toneAdjustments[hueIndex].HueUniformity * hueWeight;
var nextToneHueWeight = toneAdjustments[nextHueIndex].HueUniformity * nextHueWeight;
hue = hue * (1 - toneHueWeight - nextToneHueWeight) +
toneHue * toneHueWeight +
nextToneHue * nextToneHueWeight;
}

var haLow = toneAdjustments[hueIndex].AdjustHue;
var haHigh = FixHue(toneAdjustments[hueIndex + NumberOfHues].AdjustHue, haLow);
var haLowNext = FixHue(toneAdjustments[nextHueIndex].AdjustHue, haLow);
var haHighNext = FixHue(toneAdjustments[nextHueIndex + NumberOfHues].AdjustHue, haLowNext);
double hueVectorX = 0;
double hueVectorY = 0;
AddHueVector(hue + haLow, toneAdjustments[hueIndex].AdjustSaturation, hueWeight * lowSaturationWeight, ref hueVectorX, ref hueVectorY);
AddHueVector(hue + haHigh, toneAdjustments[hueIndex + NumberOfHues].AdjustSaturation, hueWeight * highSaturationWeight, ref hueVectorX, ref hueVectorY);
AddHueVector(hue + haLowNext, toneAdjustments[nextHueIndex].AdjustSaturation, nextHueWeight * lowSaturationWeight, ref hueVectorX, ref hueVectorY);
AddHueVector(hue + haHighNext, toneAdjustments[nextHueIndex + NumberOfHues].AdjustSaturation, nextHueWeight * highSaturationWeight, ref hueVectorX, ref hueVectorY);
GetHueAndSaturation(hueVectorX, hueVectorY, hue, out var h, out var saturationAdjust);

var s = src[xx + 1] * saturationAdjust;

var i = src[xx + 2] *
((toneAdjustments[hueIndex].AdjustIntensity * lowSaturationWeight + toneAdjustments[hueIndex + NumberOfHues].AdjustIntensity * highSaturationWeight) * hueWeight +
(toneAdjustments[nextHueIndex].AdjustIntensity * lowSaturationWeight + toneAdjustments[nextHueIndex + NumberOfHues].AdjustIntensity * highSaturationWeight) * nextHueWeight);

ColorTransformHSI2RGB(h, s, i, out dst[xx], out dst[xx + 1], out dst[xx + 2]);
xx += 3;
}
}
}
});
}

private static float FixHue(float hueAdjust, float hueAdjustBaseBase)
{
if (hueAdjust < hueAdjustBaseBase - 0.5f)
hueAdjust += 1;
else if (hueAdjust > hueAdjustBaseBase + 0.5f)
hueAdjust -= 1;
return hueAdjust;
}

private static void AddHueVector(float hue, float saturation, float weight, ref double x, ref double y)
{
var (sin, cos) = Math.SinCos(hue * (Math.PI * 2));
x += weight * saturation * cos;
y += weight * saturation * sin;
}

private static void GetHueAndSaturation(double x, double y, float fallbackHue, out float hue, out float saturation)
{
saturation = (float)Math.Sqrt(x * x + y * y);
if (saturation > 0)
{
hue = (float)(Math.Atan2(y, x) / (Math.PI * 2));
if (hue < 0)
hue++;
}
else
hue = fallbackHue;
}
}
}
14 changes: 7 additions & 7 deletions PhotoLocator/Controls/ColorToneControl.xaml.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -130,12 +130,12 @@ void UpdateToneControlImage()
var rotation = _viewModel.ToneRotation;
for (int i = 0; i < ToneAdjustments.Length; i++)
{
var p1 = HS2XY(ToneAdjustments[i].ToneHue + rotation, 0.5);
var p2 = HS2XY(ToneAdjustments[i].ToneHue + rotation + ToneAdjustments[i].AdjustHue, 0.5 * ToneAdjustments[i].AdjustSaturation);
var p1 = HS2XY(ToneAdjustments[i].ToneHue + rotation, ToneAdjustments[i].ToneSaturation);
var p2 = HS2XY(ToneAdjustments[i].ToneHue + rotation + ToneAdjustments[i].AdjustHue, ToneAdjustments[i].ToneSaturation * ToneAdjustments[i].AdjustSaturation);

var group = new GeometryGroup();
group.Children.Add(new EllipseGeometry(p1, 2, 2));
group.Children.Add(new EllipseGeometry(p2, 2, 2));
group.Children.Add(new EllipseGeometry(p2, 1.5, 1.5));
group.Children.Add(new LineGeometry(p1, p2));

double thickness;
Expand All @@ -152,7 +152,7 @@ void UpdateToneControlImage()
ColorToneAdjustOperation.ColorTransformRGB2HSI(color[0], color[1], color[2], out float h, out float s, out _);
var xy = HS2XY(h, s);
var group = new GeometryGroup();
group.Children.Add(new EllipseGeometry(xy, 2, 2));
group.Children.Add(new EllipseGeometry(xy, 1.5, 1.5));
var drawing = new GeometryDrawing(Brushes.Transparent, new Pen(Brushes.White, InactivePenThickness), group);
drawings.Children.Add(drawing);
}
Expand Down Expand Up @@ -187,7 +187,7 @@ private void HandleMouseMove(object sender, MouseEventArgs e)
else if (h < -0.5f)
h += 1;
_viewModel.HueAdjust = h;
_viewModel.SaturationAdjust = s * 2f;
_viewModel.SaturationAdjust = s / ToneAdjustments[ActiveToneIndex].ToneSaturation;
UpdateToneControlImage();
}
}
Expand All @@ -198,8 +198,8 @@ private void HandleMouseMove(object sender, MouseEventArgs e)
_highlightTone = -1;
for (int i = 0; i < ToneAdjustments.Length; i++)
{
var p1 = HS2XY(ToneAdjustments[i].ToneHue + rotation, 0.5);
var p2 = HS2XY(ToneAdjustments[i].ToneHue + rotation + ToneAdjustments[i].AdjustHue, 0.5 * ToneAdjustments[i].AdjustSaturation);
var p1 = HS2XY(ToneAdjustments[i].ToneHue + rotation, ToneAdjustments[i].ToneSaturation);
var p2 = HS2XY(ToneAdjustments[i].ToneHue + rotation + ToneAdjustments[i].AdjustHue, ToneAdjustments[i].ToneSaturation * ToneAdjustments[i].AdjustSaturation);
var distance = SqrDistance(p1, pt);
if (distance < bestDistance)
{
Expand Down
2 changes: 2 additions & 0 deletions PhotoLocator/LocalContrastView.xaml
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -46,6 +46,8 @@
<MenuItem Header="Save adjustments (Ctrl+S)" Command="{Binding SaveAdjustmentsCommand}" />
<MenuItem Header="Load adjustments (Ctrl+O)" Command="{Binding LoadAdjustmentsCommand}" />
<MenuItem Header="Restore last used values (Ctrl+Shift+R)" Command="{Binding RestoreLastUsedValuesCommand}" />
<Separator/>
<MenuItem Header="Dual color tone mode" IsCheckable="True" IsChecked="{Binding IsDualToneModeEnabled}"/>
</ContextMenu>
</Window.ContextMenu>

Expand Down
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