/// <summary>
/// Scales the <see cref="Image"/> in both dimensions without changing its resolution.
/// </summary>
/// <param name="dst">The destination <see cref="Image"/>. Can be <b>null</b>.</param>
/// <param name="scaleFactorX">The horizontal scaling factor.</param>
/// <param name="scaleFactorY">The vertical scaling factor.</param>
/// <param name="options">The scaling options.</param>
/// <returns>
/// The destination <see cref="Image"/>.
/// </returns>
public Image Scale(Image dst, double scaleFactorX, double scaleFactorY, ScalingOptions options)
{
int newWidth = (int)((this.Width * scaleFactorX) + 0.5);
int newHeight = (int)((this.Height * scaleFactorY) + 0.5);
return(this.ScaleToSize(dst, newWidth, newHeight, options));
}
/// <summary>
/// Fits the <see cref="Image"/> into the area of specified dimensions.
/// </summary>
/// <param name="width">The width, in pixels, of the required image.</param>
/// <param name="height">The height, in pixels, of the required image.</param>
/// <param name="options">The scaling options.</param>
/// <returns>
/// A new scaled <see cref="Image"/>.
/// </returns>
/// <exception cref="InvalidOperationException">
/// The operation cannot be performed on the image with current color depth.
/// </exception>
/// <remarks>
/// This method modifies the current <see cref="Image"/> by resizing and inflating it when necessary.
/// The resulting image should be <paramref name="width"/> x <paramref name="height"/> in size.
/// </remarks>
public Image FitToSize(int width, int height, ScalingOptions options)
{
Image dst = this;
// if image is bigger than required, crop black area first
// try to preserve black area relative position within the image
if (dst.Width > width || dst.Height > height)
{
Rectangle blackArea = dst.BlackArea();
if (!blackArea.IsEmpty && blackArea != dst.Bounds)
{
////dst = dst.Crop(blackArea);
if (blackArea.Height < height)
{
int dy = Core.MinMax.Min((height - blackArea.Height) / 2, blackArea.Y, dst.Height - blackArea.Bottom);
blackArea.Inflate(0, dy, 0, height - blackArea.Height - dy);
}
if (width > 0 && blackArea.Width < width)
{
int dx = Core.MinMax.Min((width - blackArea.Width) / 2, blackArea.X, dst.Width - blackArea.Right);
blackArea.Inflate(dx, 0, width - blackArea.Width - dx, 0);
}
blackArea.Intersect(dst.Bounds);
if (blackArea != dst.Bounds)
{
dst = dst.Crop(blackArea);
}
}
}
if (dst.Width > width || dst.Height > height)
{
double horizontalFactor = (double)width / dst.Width;
double verticalFactor = (double)height / dst.Height;
double scaleFactor = Core.MinMax.Min(horizontalFactor, verticalFactor);
int newWidth = (int)((dst.Width * scaleFactor) + 0.5f);
int newHeight = (int)((dst.Height * scaleFactor) + 0.5f);
if (dst.Width != newWidth || dst.Height != newHeight)
{
dst.ScaleToSize(dst, newWidth, newHeight, options);
}
}
if (dst.Width < width || dst.Height < height)
{
int dx = width - dst.Width;
int dy = height - dst.Height;
dst = dst.Inflate(dx / 2, dy / 2, dx - (dx / 2), dy - (dy / 2), BorderType.BorderConst, dst.WhiteColor);
}
return(dst != this ? dst : dst.Copy(null, true));
}
/// <summary>
/// Scales the <see cref="Image"/> vertically and horizontally without changing its resolution.
/// </summary>
/// <param name="dst">The destination <see cref="Image"/>. Can be <b>null</b>.</param>
/// <param name="width">The desired width of the image, in pixels.</param>
/// <param name="height">The desired height of the image, in pixels.</param>
/// <param name="options">The scaling options.</param>
/// <returns>
/// The destination <see cref="Image"/>.
/// </returns>
public Image ScaleToSize(Image dst, int width, int height, ScalingOptions options)
{
if (width == this.Width && height == this.Height)
{
return(this.Copy(dst, true));
}
if (width <= 0)
{
throw new ArgumentException(Properties.Resources.E_InvalidWidth, nameof(width));
}
if (height <= 0)
{
throw new ArgumentException(Properties.Resources.E_InvalidHeight, nameof(height));
}
System.Windows.Media.Matrix matrix = System.Windows.Media.Matrix.Identity;
matrix.Scale((double)width / this.Width, (double)height / this.Height);
#if false
dst = this.Affine(dst, matrix, BorderType.BorderConst, this.WhiteColor);
Debug.Assert(width == dst.Width && height == dst.Height, "Image dimensions are wrong.");
return(dst);
#else
// IPP does not support 1bpp images - convert to 8bpp
Image src;
bool convert1bpp = false;
if (this.BitsPerPixel == 1)
{
src = this.Convert1To8(null);
convert1bpp = true;
}
else
{
src = this;
}
bool inplace = dst == this;
dst = src.CreateTemplate(dst, width, height, src.BitsPerPixel);
IPP.Execute(() =>
{
return(NativeMethods.resize(
src.BitsPerPixel,
src.Width,
src.Height,
src.Bits,
src.Stride8,
dst.Width,
dst.Height,
dst.Bits,
dst.Stride8,
options.InterpolationType,
options.Antialiasing,
options.ValueB,
options.ValueC,
options.Lobes,
BorderType.BorderConst,
src.WhiteColor));
});
dst.AppendTransform(new MatrixTransform(matrix));
// convert back to 1bpp
if (convert1bpp)
{
dst.Convert8To1(dst, 1);
}
if (inplace)
{
this.Attach(dst);
return(this);
}
return(dst);
#endif
}
public Image Scale(Image dst, double scaleFactor, ScalingOptions options) => this.Scale(dst, scaleFactor, scaleFactor, options);
