public static Bitmap Resize(string path, Interpolations interpolation, int width, int height)
{
Bitmap original = new Bitmap(path);
Bitmap resized = new Bitmap(width, height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
double wScale = (double)resized.Width / original.Width;
double hScale = (double)resized.Height / original.Height;
bool needsScaling = false;
switch (interpolation)
{
case Interpolations.NearestNeighbor:
// Applies nearest neighbor sampling straight
for (int i = 0; i < resized.Width; i++)
{
for (int j = 0; j < resized.Height; j++)
{
resized.SetPixel(i, j, original.GetPixel((int)(i / wScale), (int)(j / hScale)));
}
}
break;
case Interpolations.Bilinear:
if (wScale >= 0.5)
{
// Bilinear Interpolation
resized = BilinearResize(original, wScale, hScale);
// If scaling smaller than 1, applies blurring when bilinear is done
if (wScale < 1)
{
resized = Effects.Blur(resized, wScale);
}
}
else
{
// Box Filtering
resized = BoxFilterResize(original, wScale, hScale);
}
break;
case Interpolations.Bicubic:
// If scaling is smaller than 0.25,
// enlarges image using box filtering first
needsScaling = wScale < 0.25;
// First, applies box filter scaling to incrase it by 4 of its size
// Finally, applies bicubic resizing
resized = BicubicResize(
needsScaling ? BoxFilterResize(original, 4, 4) : original,
needsScaling ? 4 * wScale : wScale,
needsScaling ? 4 * hScale : hScale);
break;
case Interpolations.BicubicSmoother:
// If the scaling is smaller than 0.25,
// enlarges image using box filtering first
needsScaling = wScale < 0.25;
// First, applies box filter scaling to incrase it by 4 of its size
// Then, applies bicubic resizing
resized = BicubicResize(
needsScaling ? BoxFilterResize(original, 4, 4) : original,
needsScaling ? 4 * wScale : wScale,
needsScaling ? 4 * hScale : hScale);
// Finally, applies blurring
resized = Effects.Blur(resized, 1.15);
break;
case Interpolations.BicubicSharper:
// If the scaling is smaller than 0.25,
// enlarges image using box filtering first
needsScaling = wScale < 0.25;
// First, applies box filter scaling to incrase it by 4 of its size
// Then, applies bicubic resizing
resized = BicubicResize(
needsScaling ? BoxFilterResize(original, 4, 4) : original,
needsScaling ? 4 * wScale : wScale,
needsScaling ? 4 * hScale : hScale);
// Finally, applies blurring
resized = Effects.Blur(resized, 1.05);
break;
}
return(resized);
}
