public Bitmap MakeThumbnail(int cxThumb, int cyThumb, bool fFilter)
{
Rectangle rcSrc = XBitmap.CalcRealBounds(m_bm);
if (rcSrc.Width <= 0 || rcSrc.Height <= 0)
{
return(m_bm);
}
int cxy = Math.Max(rcSrc.Width, rcSrc.Height);
Bitmap bmDst = new Bitmap(cxy, cxy);
Graphics gDst = Graphics.FromImage(bmDst);
gDst.Clear(Color.White);
gDst.Dispose();
int xDst = (bmDst.Width - rcSrc.Width) / 2;
int yDst = (bmDst.Height - rcSrc.Height) / 2;
BitmapData bmdDst = bmDst.LockBits(
new Rectangle(0, 0, bmDst.Width, bmDst.Height),
ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
SuperBlt(rcSrc.X, rcSrc.Y, bmdDst, xDst, yDst,
rcSrc.Width, rcSrc.Height, false);
bmDst.UnlockBits(bmdDst);
Bitmap bmLarge = new Bitmap(cxThumb, cyThumb);
Graphics g = Graphics.FromImage(bmLarge);
InterpolationMode imOld = g.InterpolationMode;
g.InterpolationMode = fFilter ? InterpolationMode.Bicubic : InterpolationMode.NearestNeighbor;
PixelOffsetMode pomOld = g.PixelOffsetMode;
g.PixelOffsetMode = PixelOffsetMode.Half;
g.DrawImage(bmDst, 0, 0, cxThumb, cyThumb);
g.PixelOffsetMode = pomOld;
g.InterpolationMode = imOld;
g.Dispose();
bmDst.Dispose();
return(bmLarge);
}
