hi,

how can i save a grayscale (8bit) image? i tried using
System.Drawing.Imaging.Encoder.ColorDepth but when i try to save jpeg
wither using 8 or 1bit i always get 24bit one. when i try to save tiff i
get an exception when i try 8 or 1bit. what's going on??

here's code example:

using (Bitmap b = new Bitmap(200, 50))
using (Graphics g = Graphics.FromImage(b))
using (Font f = new Font(FontFamily.GenericSansSerif, 12))
using (StringFormat sf = new StringFormat())
{
    g.PageUnit = GraphicsUnit.Pixel;
    sf.LineAlignment = StringAlignment.Center;
    sf.Alignment = StringAlignment.Center;
    Rectangle rect = new Rectangle(0, 0, b.Width, b.Height);
    g.FillRectangle(Brushes.White, rect);
    g.DrawString(someText, f, Brushes.Black, rect, sf);
    ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
    ImageCodecInfo ici = null;
    foreach (ImageCodecInfo codec in codecs)
    {
        if (codec.MimeType == "image/jpeg")
            ici = codec;
    }
    EncoderParameters ep = new EncoderParameters(2);
    ep.Param[0] = new EncoderParameter(
        System.Drawing.Imaging.Encoder.Quality, (long)85);
    ep.Param[1] = new EncoderParameter(
        System.Drawing.Imaging.Encoder.ColorDepth, 8L);
    b.Save(fileName, ici, ep);
}