private static void SetGradientStops(LinearGradient gradient, FocusBand focusBand, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var blurArea1FirstOffset = GetOffset(gradient, focusBand.Edge1);
var blurArea2FirstOffset = GetOffset(gradient, focusBand.Edge2);
var focusBandEdge1Pixels = new Point(focusBand.Edge1.X * sourceSize.Width, focusBand.Edge1.Y * sourceSize.Height);
var focusBandEdge2Pixels = new Point(focusBand.Edge2.X * sourceSize.Width, focusBand.Edge2.Y * sourceSize.Height);
var focusBandWidth = Math.Abs(blurArea1FirstOffset - blurArea2FirstOffset);
var focusBandWidthPixels = Distance(focusBandEdge1Pixels, focusBandEdge2Pixels);
double blurAreaWidth;
if (focusBandWidthPixels > 0)
{
var scaleFactor = focusBandWidth / focusBandWidthPixels;
var blurAreaWidthPixels = (sourceSize.Height - focusBandWidthPixels) / 2 * 0.9;
if (blurAreaWidthPixels < 1.0)
{
gradient.Stops = new[] { new GradientStop() { Offset = 0.5, Color = Color.FromArgb(255, 0, 0, 0) } };
return;
}
blurAreaWidth = blurAreaWidthPixels * scaleFactor;
}
else
{
blurAreaWidth = 0.5;
applySmallBlurFocusArea = true;
}
double blurArea1LastOffset;
double blurArea2LastOffset;
if (blurArea1FirstOffset > blurArea2FirstOffset)
{
blurArea1LastOffset = blurArea1FirstOffset + blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset - blurAreaWidth;
}
else
{
blurArea1LastOffset = blurArea1FirstOffset - blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset + blurAreaWidth;
}
var stops1 = GetGradientStops(gradient, applySmallBlurFocusArea, edge1KernelGenerator, blurArea1FirstOffset, blurArea1LastOffset);
var stops2 = GetGradientStops(gradient, applySmallBlurFocusArea, edge2KernelGenerator, blurArea2FirstOffset, blurArea2LastOffset, (byte)(edge1KernelGenerator.GetKernelBands().Count));
List<GradientStop> stops = new List<GradientStop>();
stops.AddRange(stops1);
stops.AddRange(stops2);
var validStops = EnsureMinDiffBetweenPoints(stops);
gradient.Stops = validStops.ToArray();
}
public async Task RenderWithZeroWidthFocusAreaSuccedes()
{
var verticalZeroBand = new FocusBand(new Point(0.3, 0.5), new Point(0.3, 0.5));
await RenderEffect(verticalZeroBand, DepthOfFieldQuality.Full);
var horizontalZeroBand = new FocusBand(new Point(0.5, 0.7), new Point(0.5, 0.7));
await RenderEffect(horizontalZeroBand, DepthOfFieldQuality.Full);
}
public async Task RenderWithFullFocusAreaSuccedes()
{
var verticalFullBand = new FocusBand(new Point(0.0, 0.5), new Point(1.0, 0.5));
await RenderEffect(verticalFullBand, DepthOfFieldQuality.Full);
var horizontalFullBand = new FocusBand(new Point(0.5, 0.0), new Point(0.5, 1.0));
await RenderEffect(horizontalFullBand, DepthOfFieldQuality.Full);
}
private static async Task RenderEffect(FocusBand focusBand, DepthOfFieldQuality quality, [CallerMemberName] string testName = "")
{
using (var source = await KnownImages.Nurse.GetImageSourceAsync())
using (var effect = new LensTiltDepthOfFieldEffect(source, focusBand, 1.0, 1.0, quality))
using (var renderer = new JpegRenderer(effect))
{
var buffer = await renderer.RenderAsync();
await FileUtilities.SaveToPicturesLibraryAsync(buffer, "LensTiltDepthOfFieldEffectTest_" + testName + ".jpg");
}
}
/// <summary>
/// Provides a configured LinearGradient that can be used in combination with a GradientImageSource to provide a mask for the LensBlurEffect.
/// Generates a map for BlendEffect.
/// </summary>
/// <param name="band">The band that represents the focus area in the image. Pixels within this band won't be blurred.
/// Areas outside of the area will be progressively more blurred as the distance from the focus band increases.</param>
/// <param name="kernelSpanFromEdge1">Strength at Edge1.</param>
/// <param name="kernelSpanFromEdge2">Strength at Edge2.</param>
/// <returns>A LinearGradient that can be used in combination with a GradientImageSource to be used by LensBlur.</returns>
public static LinearGradient GenerateGradient(FocusBand band, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var gradient = new LinearGradient();
var lineFunction = GradientLine.CreateFunction(band);
SetGradientPoints(gradient, lineFunction);
SetGradientStops(gradient, band, sourceSize, edge1KernelGenerator, edge2KernelGenerator, applySmallBlurFocusArea);
return(gradient);
}
/// <summary>
/// Provides a configured LinearGradient that can be used in combination with a GradientImageSource to provide a mask for the LensBlurEffect.
/// Generates a map for BlendEffect.
/// </summary>
/// <param name="band">The band that represents the focus area in the image. Pixels within this band won't be blurred.
/// Areas outside of the area will be progressively more blurred as the distance from the focus band increases.</param>
/// <param name="kernelSpanFromEdge1">Strength at Edge1.</param>
/// <param name="kernelSpanFromEdge2">Strength at Edge2.</param>
/// <returns>A LinearGradient that can be used in combination with a GradientImageSource to be used by LensBlur.</returns>
public static LinearGradient GenerateGradient(FocusBand band, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var gradient = new LinearGradient();
var lineFunction = GradientLine.CreateFunction(band);
SetGradientPoints(gradient, lineFunction);
SetGradientStops(gradient, band, sourceSize, edge1KernelGenerator, edge2KernelGenerator, applySmallBlurFocusArea);
return gradient;
}
protected override MaybeTask <IImageProvider> GetEffectInternalAsync(IImageProvider source, Windows.Foundation.Size sourceSize, Windows.Foundation.Size renderSize)
{
if (m_effectEffect == null)
{
m_focus = new FocusBand(new Point(0.5, 0.3), new Point(0.5, 0.4));
m_effectEffect = new LensTiltDepthOfFieldEffect(source, m_focus, 1.0, 1.0, DepthOfFieldQuality.Preview);
}
else if (m_effectEffect.Source != source)
{
m_effectEffect.Source = source;
}
return(new MaybeTask <IImageProvider>(m_effectEffect));
}
public static Func<double, Point> CreateFunction(FocusBand band)
{
double xDiff = band.Edge1.X - band.Edge2.X;
Func<double, Point> lineFunction;
if (Math.Abs(xDiff) < 1e-3)
{
//special case to avoid divide by zero
lineFunction = (x) => new Point(band.Edge1.X, x);
}
else
{
double slope = (band.Edge2.Y - band.Edge1.Y) / (band.Edge2.X - band.Edge1.X);
double yIntercept = band.Edge1.Y - band.Edge1.X * slope;
lineFunction = (x) => new Point(x, slope * x + yIntercept);
}
return lineFunction;
}
public static Func <double, Point> CreateFunction(FocusBand band)
{
double xDiff = band.Edge1.X - band.Edge2.X;
Func <double, Point> lineFunction;
if (Math.Abs(xDiff) < 1e-3)
{
//special case to avoid divide by zero
lineFunction = (x) => new Point(band.Edge1.X, x);
}
else
{
double slope = (band.Edge2.Y - band.Edge1.Y) / (band.Edge2.X - band.Edge1.X);
double yIntercept = band.Edge1.Y - band.Edge1.X * slope;
lineFunction = (x) => new Point(x, slope * x + yIntercept);
}
return(lineFunction);
}
private static void SetGradientStops(LinearGradient gradient, FocusBand focusBand, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var blurArea1FirstOffset = GetOffset(gradient, focusBand.Edge1);
var blurArea2FirstOffset = GetOffset(gradient, focusBand.Edge2);
var focusBandEdge1Pixels = new Point(focusBand.Edge1.X * sourceSize.Width, focusBand.Edge1.Y * sourceSize.Height);
var focusBandEdge2Pixels = new Point(focusBand.Edge2.X * sourceSize.Width, focusBand.Edge2.Y * sourceSize.Height);
var focusBandWidth = Math.Abs(blurArea1FirstOffset - blurArea2FirstOffset);
var focusBandWidthPixels = Distance(focusBandEdge1Pixels, focusBandEdge2Pixels);
double blurAreaWidth;
if (focusBandWidthPixels > 0)
{
var scaleFactor = focusBandWidth / focusBandWidthPixels;
var blurAreaWidthPixels = (sourceSize.Height - focusBandWidthPixels) / 2 * 0.9;
if (blurAreaWidthPixels < 1.0)
{
gradient.Stops = new[] { new GradientStop()
{
Offset = 0.5, Color = Color.FromArgb(255, 0, 0, 0)
} };
return;
}
blurAreaWidth = blurAreaWidthPixels * scaleFactor;
}
else
{
blurAreaWidth = 0.5;
applySmallBlurFocusArea = true;
}
double blurArea1LastOffset;
double blurArea2LastOffset;
if (blurArea1FirstOffset > blurArea2FirstOffset)
{
blurArea1LastOffset = blurArea1FirstOffset + blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset - blurAreaWidth;
}
else
{
blurArea1LastOffset = blurArea1FirstOffset - blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset + blurAreaWidth;
}
var stops1 = GetGradientStops(gradient, applySmallBlurFocusArea, edge1KernelGenerator, blurArea1FirstOffset, blurArea1LastOffset);
var stops2 = GetGradientStops(gradient, applySmallBlurFocusArea, edge2KernelGenerator, blurArea2FirstOffset, blurArea2LastOffset, (byte)(edge1KernelGenerator.GetKernelBands().Count));
List <GradientStop> stops = new List <GradientStop>();
stops.AddRange(stops1);
stops.AddRange(stops2);
var validStops = EnsureMinDiffBetweenPoints(stops);
gradient.Stops = validStops.ToArray();
}
public GradientLine(FocusBand band)
{
m_focusBand = band;
IsVertical = (band.Edge1.X - band.Edge2.X) < 1e-3;
IsHorizontal = (band.Edge1.Y - band.Edge2.Y) < 1e-3;
}
public GradientLine(FocusBand band)
{
m_focusBand = band;
IsVertical = (band.Edge1.X - band.Edge2.X) < 1e-3;
IsHorizontal = (band.Edge1.Y - band.Edge2.Y) < 1e-3;
}
