"Hardy Wang" <hardyw***@hotmail.com> wrote in message
news:eFY1GGLRGHA.4792@TK2MSFTNGP14.phx.gbl...
> 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
>
>
>
>