Bitmap.Save "Generic Error"

Question

When I run my application the following error get's thrown in my face "A generic error occurred in GDI+." I've looked around and seen people have similar errors, but have found no real solution, or it is a real pain in the butt to implement. And those that have not gotten a solution have not posted their code.

So I thought I might as well give it a shot and throw another thread up about how to fix this error. This is my Code & Error

            Random r = new Random();
            DirectoryInfo di = new DirectoryInfo(folderbrowser.SelectedPath);
            FileInfo[] fi = di.GetFiles().Where(f => extensions.Contains(f.Extension.ToLower())).ToArray();
            for (int i = 0; i < imageCount; i++)
            {
                int img1 = r.Next(imageCount);
                int img2 = r.Next(imageCount);
                while (img2 == img1)
                    img2 = r.Next(imageCount);
                pic1.Image = Image.FromFile(fi[img1].FullName);
                pic2.Image = Image.FromFile(fi[img2].FullName);
                Image i1 = pic1.Image;
                Image i2 = pic2.Image;
                Bitmap bitmap = new Bitmap(i1.Width + i2.Width, 1080);
                using (Graphics g = Graphics.FromImage(bitmap))
                {
                    g.DrawImage(i1, 0, 0);
                    g.DrawImage(i2, i2.Width, 0);
                }
                bitmap.Save(@"C:\TEST\Image_"+i.ToString());                   
            }

And here's the Error code

System.Runtime.InteropServices.ExternalException was unhandled
  Message=A generic error occurred in GDI+.
  Source=System.Drawing
  ErrorCode=-2147467259
  StackTrace:
       at System.Drawing.Image.Save(String filename, ImageCodecInfo encoder, EncoderParameters encoderParams)
       at System.Drawing.Image.Save(String filename, ImageFormat format)
       at System.Drawing.Image.Save(String filename)
       at WallpaperMerger.Form1.btn_merge_Click(Object sender, EventArgs e) in C:\Users\PeppeJ\documents\visual studio 2010\Projects\WallpaperMerger\WallpaperMerger\Form1.cs:line 113
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
       at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ButtonBase.WndProc(Message& m)
       at System.Windows.Forms.Button.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(Form mainForm)
       at WallpaperMerger.Program.Main() in C:\Users\PeppeJ\documents\visual studio 2010\Projects\WallpaperMerger\WallpaperMerger\Program.cs:line 18
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
       at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException: 

So what do you guys here at StackOverflow think. Am I the same boat as the others and have to type a ridiculously complex code to solve this problem, or have I made a simple mistake and it's easy to correct?

If you want to test it yourself if that might somehow help, here's a link to the Debug Build

Simply tick "Use Multiple Files", select a folder containing image files (C:\Users\Public\Pictures\Sample Pictures) for instance. Hit Merge.

I'd like to add that I use Bitmap.Save in this function, and it works flawlessly.

        Bitmap bitmap = new Bitmap(pic1.Image.Width + pic2.Image.Width, 1080);
        using (Graphics g = Graphics.FromImage(bitmap))
        {
            g.DrawImage(pic1.Image, 0, 0);
            g.DrawImage(pic2.Image, pic1.Image.Width, 0);
        }
        if (savepicfile.ShowDialog() == DialogResult.OK)
            bitmap.Save(savepicfile.FileName);

In the above function files are loaded like this:

    DialogResult result = pic1file.ShowDialog();
    if (result == DialogResult.OK)
        pic1.Image = Image.FromFile(pic1file.FileName);

Something else worth mentioning is that "picX" is a "System.Windows.Forms.PictureBox" object.

Answer 1

In my experience, 99% of the time this error is caused by an issue where either:

1. You don't have permission to write the file.
2. The file you're trying to write to is locked by another process.

Occasionally I've run into it when:

• I'm drawing GraphicPaths with zero points in them.
• I'm not property disposing of my GDI+ objects. (possibly related to option 2 above)

I'd check the first two things first. If that can be ruled out I can see where you're not properly disposing of a few objects in the code you provided. I'd clean that up. GDI+ isn't particularly cooperative with .NET's GC if you aren't calling Dispose() when you're supposed to.

        var r = new Random();
        var di = new DirectoryInfo(folderbrowser.SelectedPath);
        var fi = di.GetFiles().Where(f => extensions.Contains(f.Extension.ToLower())).ToArray();
        for (var i = 0; i < imageCount; i++)
        {
            var img1 = r.Next(imageCount);
            var img2 = r.Next(imageCount);
            while (img2 == img1) 
            {
                img2 = r.Next(imageCount);
            }
            pic1.Image = Image.FromFile(fi[img1].FullName);
            pic2.Image = Image.FromFile(fi[img2].FullName);
            var i1 = pic1.Image;
            var i2 = pic2.Image;
            using (var bitmap = new Bitmap(i1.Width + i2.Width, 1080))
            using (var g = Graphics.FromImage(bitmap))
            {
                g.DrawImage(i1, 0, 0);
                g.DrawImage(i2, i2.Width, 0);
                bitmap.Save(@"C:\TEST\Image_"+i.ToString());
            }                   
        }

---

EDIT: More ideas (Well, really clarification of number 2 above)...

• If you have a PictureBox or other control in your app referencing the images in your C:\TEST directory that you're trying to write, you can see this error.
• If you have other code reading the image you're trying to write to you can see this error.
• If an external process, such as your IDE, an image viewer/editor, etc. has the file open you can see this error.

Debugging ideas:

• Try setting a break point on the Save call. When you get to it, use the tips found here to figure out what process might be accessing the file: How do I find out which process is locking a file using .NET?
• Try just deleting the files first to see if it allows you to save if they're not their.
• Try setting full permissions for "Everyone" on the directory you're writing to (Don't leave it like this, though)
• Make sure the width of the image you're trying to save is a number greater than zero. I noticed you're setting that programatically.
• Make sure the width of the image you're trying to save isn't ridiculously huge (an maybe you're running into a memory issue?)

Answer 2

I found the answer, the directory "\TEST\" didn't exist. When I created it , it worked flawlessly.

Answer 3

I had this exact problem, and what fixed it was to wrap the Bitmap in the using clause; Bitmap needs to be disposed as well

using (Bitmap bmp = new Bitmap()) 
{
    // Bitmap operation
}

Answer 4

Try doing the bitmap.Save before you dispose of the Graphics object:

Bitmap bitmap = new Bitmap(i1.Width + i2.Width, 1080);
using (Graphics g = Graphics.FromImage(bitmap))
{
    g.DrawImage(i1, 0, 0);
    g.DrawImage(i2, i2.Width, 0);
    bitmap.Save(@"C:\TEST\Image_"+i.ToString()); 
}