Hi,
   I found a piece of code to add drop shadow to a photo like below, after
I save the image, it is actually a BMP file even though I specify a JPG file
extension (see http://img140.imageshack.us/my.php?image=resized11wz.jpg). If
I force to save in JPG format (see the commented line), then the whole
shadow is a messup (see
http://img70.imageshack.us/my.php?image=resized29cy.jpg).

   I am just wandering are there any attributes / formats not supported by
JPG format?

   Did I do something wrong?

Image original = Image.FromFile(@"H:\Input\P1010001.JPG");
Image resized = RectangleDropShadow(original, Color.Black, 10, 200);
resized.Save(@"H:\Output\resized.jpg");
//resized.Save(@"H:\Output\resized.jpg", ImageFormat.Jpeg);

       public Image RectangleDropShadow (Image original, Color shadowColor,
int depth, int maxOpacity) {
           Bitmap tn = new Bitmap(original.Width + depth, original.Height +
depth);
           Graphics tg = Graphics.FromImage(tn);

           Rectangle rc = new Rectangle(0, 0, original.Width + depth,
original.Height + depth);

           //calculate the opacities
           Color darkShadow = Color.FromArgb(maxOpacity, shadowColor);
           Color lightShadow = Color.FromArgb(0, shadowColor);

           //Create a brush that will create a softshadow circle
           GraphicsPath gp = new GraphicsPath();
           gp.AddEllipse(0, 0, 2 * depth, 2 * depth);
           PathGradientBrush pgb = new PathGradientBrush(gp);
           pgb.CenterColor = darkShadow;
           pgb.SurroundColors = new Color[] { lightShadow };

           //generate a softshadow pattern that can be used to paint the
shadow
           Bitmap patternbm = new Bitmap(2 * depth, 2 * depth);
           Graphics g = Graphics.FromImage(patternbm);
           g.FillEllipse(pgb, 0, 0, 2 * depth, 2 * depth);
           g.Dispose();
           pgb.Dispose();

           SolidBrush sb = new SolidBrush(Color.FromArgb(maxOpacity,
shadowColor));
           tg.FillRectangle(sb, rc.Left + depth, rc.Top + depth, rc.Width -
(2 * depth), rc.Height - (2 * depth));
           sb.Dispose();

           //top left corner
           tg.DrawImage(patternbm, new Rectangle(rc.Left, rc.Top, depth,
depth), 0, 0, depth, depth,
               GraphicsUnit.Pixel);

           //top side
           tg.DrawImage(patternbm, new Rectangle(rc.Left + depth, rc.Top,
rc.Width - (2 * depth), depth),
               depth, 0, 1, depth, GraphicsUnit.Pixel);

           //top right corner
           tg.DrawImage(patternbm, new Rectangle(rc.Right - depth, rc.Top,
depth, depth),
               depth, 0, depth, depth, GraphicsUnit.Pixel);

           //right side
           tg.DrawImage(patternbm, new Rectangle(rc.Right - depth, rc.Top +
depth,
               depth, rc.Height - (2 * depth)), depth, depth, depth, 1,
               GraphicsUnit.Pixel);

           //bottom left corner
           tg.DrawImage(patternbm, new Rectangle(rc.Right - depth,
rc.Bottom - depth, depth, depth),
               depth, depth, depth, depth, GraphicsUnit.Pixel);

           //bottom side
           tg.DrawImage(patternbm, new Rectangle(rc.Left + depth,
rc.Bottom - depth, rc.Width - (2 * depth), depth),
               depth, depth, 1, depth, GraphicsUnit.Pixel);

           //bottom left corner
           tg.DrawImage(patternbm, new Rectangle(rc.Left, rc.Bottom -
depth, depth, depth),
               0, depth, depth, depth, GraphicsUnit.Pixel);

           //left side
           tg.DrawImage(patternbm, new Rectangle(rc.Left, rc.Top + depth,
depth, rc.Height - (2 * depth)),
               0, depth, depth, 1, GraphicsUnit.Pixel);

           patternbm.Dispose();

           tg.DrawImage(original, new Rectangle(0, 0, original.Width,
original.Height),
               0, 0, original.Width, original.Height, GraphicsUnit.Pixel);

           return (Image)tn;
       }

Regards
Hardy