/// <inheritdoc/>
protected override unsafe void OnApply(ImageFrame <TPixel> source, ImageFrame <TPixel> cloned, Rectangle sourceRectangle, Configuration configuration)
{
// Jump out, we'll deal with that later.
if (source.Width == cloned.Width && source.Height == cloned.Height && sourceRectangle == this.ResizeRectangle)
{
// the cloned will be blank here copy all the pixel data over
source.GetPixelSpan().CopyTo(cloned.GetPixelSpan());
return;
}
int width = this.Width;
int height = this.Height;
int sourceX = sourceRectangle.X;
int sourceY = sourceRectangle.Y;
int startY = this.ResizeRectangle.Y;
int endY = this.ResizeRectangle.Bottom;
int startX = this.ResizeRectangle.X;
int endX = this.ResizeRectangle.Right;
int minX = Math.Max(0, startX);
int maxX = Math.Min(width, endX);
int minY = Math.Max(0, startY);
int maxY = Math.Min(height, endY);
if (this.Sampler is NearestNeighborResampler)
{
// Scaling factors
float widthFactor = sourceRectangle.Width / (float)this.ResizeRectangle.Width;
float heightFactor = sourceRectangle.Height / (float)this.ResizeRectangle.Height;
Parallel.For(
minY,
maxY,
configuration.ParallelOptions,
y =>
{
// Y coordinates of source points
Span <TPixel> sourceRow = source.GetPixelRowSpan((int)(((y - startY) * heightFactor) + sourceY));
Span <TPixel> targetRow = cloned.GetPixelRowSpan(y);
for (int x = minX; x < maxX; x++)
{
// X coordinates of source points
targetRow[x] = sourceRow[(int)(((x - startX) * widthFactor) + sourceX)];
}
});
return;
}
// Interpolate the image using the calculated weights.
// A 2-pass 1D algorithm appears to be faster than splitting a 1-pass 2D algorithm
// First process the columns. Since we are not using multiple threads startY and endY
// are the upper and lower bounds of the source rectangle.
// TODO: Using a transposed variant of 'firstPassPixels' could eliminate the need for the WeightsWindow.ComputeWeightedColumnSum() method, and improve speed!
using (var firstPassPixels = new Buffer2D <Vector4>(width, source.Height))
{
firstPassPixels.Clear();
Parallel.For(
0,
sourceRectangle.Bottom,
configuration.ParallelOptions,
y =>
{
// TODO: Without Parallel.For() this buffer object could be reused:
using (var tempRowBuffer = new Buffer <Vector4>(source.Width))
{
Span <Vector4> firstPassRow = firstPassPixels.GetRowSpan(y);
Span <TPixel> sourceRow = source.GetPixelRowSpan(y);
PixelOperations <TPixel> .Instance.ToVector4(sourceRow, tempRowBuffer, sourceRow.Length);
if (this.Compand)
{
for (int x = minX; x < maxX; x++)
{
WeightsWindow window = this.HorizontalWeights.Weights[x - startX];
firstPassRow[x] = window.ComputeExpandedWeightedRowSum(tempRowBuffer, sourceX);
}
}
else
{
for (int x = minX; x < maxX; x++)
{
WeightsWindow window = this.HorizontalWeights.Weights[x - startX];
firstPassRow[x] = window.ComputeWeightedRowSum(tempRowBuffer, sourceX);
}
}
}
});
// Now process the rows.
Parallel.For(
minY,
maxY,
configuration.ParallelOptions,
y =>
{
// Ensure offsets are normalised for cropping and padding.
WeightsWindow window = this.VerticalWeights.Weights[y - startY];
Span <TPixel> targetRow = cloned.GetPixelRowSpan(y);
if (this.Compand)
{
for (int x = 0; x < width; x++)
{
// Destination color components
Vector4 destination = window.ComputeWeightedColumnSum(firstPassPixels, x, sourceY);
destination = destination.Compress();
ref TPixel pixel = ref targetRow[x];
pixel.PackFromVector4(destination);
}
}
else
{
for (int x = 0; x < width; x++)
{
// Destination color components
Vector4 destination = window.ComputeWeightedColumnSum(firstPassPixels, x, sourceY);
ref TPixel pixel = ref targetRow[x];
pixel.PackFromVector4(destination);
}
}
});
/// <inheritdoc/>
protected override unsafe void OnApply(ImageBase <TColor> source, Rectangle sourceRectangle)
{
// Jump out, we'll deal with that later.
if (source.Width == this.Width && source.Height == this.Height && sourceRectangle == this.ResizeRectangle)
{
return;
}
int width = this.Width;
int height = this.Height;
int sourceX = sourceRectangle.X;
int sourceY = sourceRectangle.Y;
int startY = this.ResizeRectangle.Y;
int endY = this.ResizeRectangle.Bottom;
int startX = this.ResizeRectangle.X;
int endX = this.ResizeRectangle.Right;
int minX = Math.Max(0, startX);
int maxX = Math.Min(width, endX);
int minY = Math.Max(0, startY);
int maxY = Math.Min(height, endY);
if (this.Sampler is NearestNeighborResampler)
{
// Scaling factors
float widthFactor = sourceRectangle.Width / (float)this.ResizeRectangle.Width;
float heightFactor = sourceRectangle.Height / (float)this.ResizeRectangle.Height;
using (PixelAccessor <TColor> targetPixels = new PixelAccessor <TColor>(width, height))
{
using (PixelAccessor <TColor> sourcePixels = source.Lock())
{
Parallel.For(
minY,
maxY,
this.ParallelOptions,
y =>
{
// Y coordinates of source points
int originY = (int)(((y - startY) * heightFactor) + sourceY);
for (int x = minX; x < maxX; x++)
{
// X coordinates of source points
targetPixels[x, y] = sourcePixels[(int)(((x - startX) * widthFactor) + sourceX), originY];
}
});
}
// Break out now.
source.SwapPixelsBuffers(targetPixels);
return;
}
}
// Interpolate the image using the calculated weights.
// A 2-pass 1D algorithm appears to be faster than splitting a 1-pass 2D algorithm
// First process the columns. Since we are not using multiple threads startY and endY
// are the upper and lower bounds of the source rectangle.
// TODO: Using a transposed variant of 'firstPassPixels' could eliminate the need for the WeightsWindow.ComputeWeightedColumnSum() method, and improve speed!
using (PixelAccessor <TColor> targetPixels = new PixelAccessor <TColor>(width, height))
{
using (PixelAccessor <TColor> sourcePixels = source.Lock())
using (Buffer2D <Vector4> firstPassPixels = new Buffer2D <Vector4>(width, source.Height))
{
firstPassPixels.Clear();
Parallel.For(
0,
sourceRectangle.Bottom,
this.ParallelOptions,
y =>
{
// TODO: Without Parallel.For() this buffer object could be reused:
using (Buffer <Vector4> tempRowBuffer = new Buffer <Vector4>(sourcePixels.Width))
{
BufferSpan <TColor> sourceRow = sourcePixels.GetRowSpan(y);
BulkPixelOperations <TColor> .Instance.ToVector4(
sourceRow,
tempRowBuffer,
sourceRow.Length);
if (this.Compand)
{
for (int x = minX; x < maxX; x++)
{
WeightsWindow window = this.HorizontalWeights.Weights[x - startX];
firstPassPixels[x, y] = window.ComputeExpandedWeightedRowSum(tempRowBuffer);
}
}
else
{
for (int x = minX; x < maxX; x++)
{
WeightsWindow window = this.HorizontalWeights.Weights[x - startX];
firstPassPixels[x, y] = window.ComputeWeightedRowSum(tempRowBuffer);
}
}
}
});
// Now process the rows.
Parallel.For(
minY,
maxY,
this.ParallelOptions,
y =>
{
// Ensure offsets are normalised for cropping and padding.
WeightsWindow window = this.VerticalWeights.Weights[y - startY];
if (this.Compand)
{
for (int x = 0; x < width; x++)
{
// Destination color components
Vector4 destination = window.ComputeWeightedColumnSum(firstPassPixels, x);
destination = destination.Compress();
TColor d = default(TColor);
d.PackFromVector4(destination);
targetPixels[x, y] = d;
}
}
else
{
for (int x = 0; x < width; x++)
{
// Destination color components
Vector4 destination = window.ComputeWeightedColumnSum(firstPassPixels, x);
TColor d = default(TColor);
d.PackFromVector4(destination);
targetPixels[x, y] = d;
}
}
});
}
source.SwapPixelsBuffers(targetPixels);
}
}
