How to create image from bitmap and save it - c#-4.0

Question

Here is sample code that I'm tryin to make work, but no luck so far.
Bitmap bitmap = new Bitmap((Stream)Cache["images"]);
Graphics g = Graphics.FromImage(bitmap);
StringFormat strFrmt = new StringFormat();
strFrmt.Alignment = StringAlignment.Center;
SolidBrush btmForeColor = new SolidBrush(Color.Green);
SolidBrush btmBackColor = new SolidBrush(Color.Black);
Font btmFont = new Font("Verdana",7);
SizeF textSize = new SizeF();
textSize = g.MeasureString("Copyright", btmFont);
float x = ((float) bitmap.Width - textSize.Width - 3);
float y = ((float) bitmap.Height - textSize.Height - 3);
float w = ((float) x + textSize.Width);
float h = ((float) y + textSize.Height);
RectangleF textArea = new RectangleF(x,y,w,h);
g.FillRectangle(btmBackColor,textArea);
g.DrawString("Copyright",btmFont,btmForeColor,textArea);
btmForeColor.Dispose();
btmBackColor.Dispose();
btmFont.Dispose();
g.Dispose();
As you can see from the code, I'm getin Stream, and creatin bitmap, then making some changes upon bitmap, and now I want to save my bitmap object, but can't figure out how, I made some research in internet, but all the examples/articles/forum posts were for cases when you have some image file on the server, and want to make changes, in my case, I just have some stream, and want to save bitmap object in specific path. How can I do this ? Any kind of help would be appreciated.

Answer 1

Surely its just bitmap.save? or one of its overloads? g is really drawing on the bitmap.
** update
Bitmap bitmap = new Bitmap(#"C:\Users\mike\Pictures\Panasonic\P1000016.jpg");
Graphics g = Graphics.FromImage(bitmap);
StringFormat strFrmt = new StringFormat();
strFrmt.Alignment = StringAlignment.Center;
SolidBrush btmForeColor = new SolidBrush(Color.Green);
SolidBrush btmBackColor = new SolidBrush(Color.Black);
Font btmFont = new Font("Verdana", 90);
SizeF textSize = new SizeF();
textSize = g.MeasureString("Copyright", btmFont);
float x = ((float)bitmap.Width - textSize.Width - 3);
float y = ((float)bitmap.Height - textSize.Height - 3);
float w = ((float)x + textSize.Width);
float h = ((float)y + textSize.Height);
RectangleF textArea = new RectangleF(x, y, w, h);
g.FillRectangle(btmBackColor, textArea);
g.DrawString("Copyright", btmFont, btmForeColor, textArea);
btmForeColor.Dispose();
btmBackColor.Dispose();
btmFont.Dispose();
g.Dispose();
bitmap.Save(#"C:\Users\mike\Pictures\Panasonic\P1000016_0.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
this works for me, had to increase font size though.

Answer 2

seems I found a solution
var photoPath = Server.MapPath("~/" + AsyncFileUpload1.FileName);
if (File.Exists(photoPath))
{
File.Delete(photoPath);
}
using (var mainFile = File.Create(photoPath))
{
// dostuff()
bitmap.Save(mainFile, image.RawFormat);
}
I had to create file before saving it. Thank you Mike for beeing with me in this, I'm really appreciated!!!