I'm getting an unhandled exception when i choose "grab a frame":

"Object reference not set to an instance of an object"
************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
   at System.Drawing.Bitmap..ctor(Image original)
   at SampleGrabberNET.UnsafeBitmap..ctor(Bitmap bitmapRef)
   at WebCam_Signature.MainForm.GetFullFrameBitmap()
   at WebCam_Signature.FineTuneTrackColorsForm.GrabAFrameButton_MouseClick(Object sender, MouseEventArgs 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.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

-mouser (June 25, 2008, 04:13 PM)

Is your webcam turned on? I didn't realize that the program would throw an exception when the webcam is not available and you try to go into "Fine Tune Tracking Color". I will fix that in a bit. You can safely press the continue button if that pops up.

Alrighty,
I have made some improvements to Webcam Signature and the newest version is now 1.1. The primary thing is that I added the capability to select the tracking color by just clicking on a point on an image from the webcam. The greatly simplifies selecting the tracking color. I have also added the capability to statically or dynamically filter out the background for greater robustness. Get the latest version for testing at http://webcamsignature.wikidot.com/download-webcam-signature

I have sent the source code to mouser if anyone needs it. The source code and the program are open source under a GNU General Public License V3 and I'll post it on the website in a few days.

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After playing around with Webcam Signature 1.0, I've got an idea that should greatly enhance the ability of the program to track the pen and filter out background colors. I'm going to try to code it in time for the contest closing. I've just got to plan it out and think it through so I'll know if it'll work. It might take too much processing power. We'll see if it works or not.