void ExportToGrayscale()
{
SaveFileDialog sfd = new SaveFileDialog();
sfd.Filter = "Jpeg Files (*.jpg)|*.jpg";
sfd.CheckPathExists = true;
// the user should pick the output file
if (sfd.ShowDialog() == DialogResult.OK)
{
// the render target object
var rt = _d2dContext;
// create the target Direct2D bitmap for the given DXGI.Surface
var bpTarget = new D2D.BitmapProperties1(
new D2D.PixelFormat(DXGI.Format.B8G8R8A8_UNorm, D2D.AlphaMode.Premultiplied),
(float)_bitmap.DpiX, (float)_bitmap.DpiY, D2D.BitmapOptions.Target | D2D.BitmapOptions.CannotDraw);
Size2L bmpSize = new Size2L(_bitmap.PixelWidth, _bitmap.PixelHeight);
var targetBmp = D2D.Bitmap1.Create(rt, bmpSize, bpTarget);
// associate the target bitmap with render target
rt.SetTarget(targetBmp);
// start drawing
rt.BeginDraw();
// clear the target bitmap
rt.Clear(null);
// convert C1Bitmap image to Direct2D image
var d2dBitmap = _bitmap.ToD2DBitmap1(rt, D2D.BitmapOptions.None);
// create the Grayscale effect
_colorMatrix.SetInput(0, d2dBitmap);
_colorMatrix.Matrix = new Matrix5x4(
0.299f, 0.299f, 0.299f, 0,
0.587f, 0.587f, 0.587f, 0,
0.114f, 0.114f, 0.114f, 0,
0, 0, 0, 1,
0, 0, 0, 0
);
// and draw the result
rt.DrawImage(_colorMatrix, Point2F.Empty);
d2dBitmap.Dispose();
// now let's draw the text label with shadow
rt.Transform = Matrix3x2.Rotation(-90f) * Matrix3x2.Translation(6f, 344f);
_brush.SetColor(ColorF.White);
rt.DrawTextLayout(new Point2F(-1f, -1f), _textLayout, _brush);
_brush.SetColor(ColorF.DimGray);
rt.DrawTextLayout(Point2F.Empty, _textLayout, _brush);
rt.Transform = Matrix3x2.Identity;
// finish drawing (all drawing commands are executed now)
rt.EndDraw();
// detach the target bitmap
rt.SetTarget(null);
// create a temporary C1Bitmap object
var exportBitmap = new C1Bitmap(_bitmap.ImagingFactory);
// import the image from Direct2D target bitmap to C1Bitmap
var srcRect = new RectL(_bitmap.PixelWidth, _bitmap.PixelHeight);
exportBitmap.Import(targetBmp, rt, srcRect);
targetBmp.Dispose();
// save the image to file
exportBitmap.SaveAsJpeg(sfd.FileName, null);
exportBitmap.Dispose();
}
}
