problem with PictureBox

See more:

C#

forms

picturebox

Hi
I am having a problem with my picture box i am getting stream from web cam displaying it in my picturebox, now when i call picturebox.refres() it works fine but it does not execute the code after refresh method instead it goes to the top of that function.If i dont call the refresh method it shows the first frame and then big red X with white background.The following code is in the eventhandler which gives new frames to bitmap.

currFrame = bitmap1;
bitmap1 = eventArgs.Frame;
copy = bitmap1;
Difference filter = new Difference(currFrame);
    // apply the filter
Bitmap resultImage = filter.Apply(copy);

pictureBox4.Image = resultImage;
pictureBox4.Refresh();
    //It works fine but it will not execute the code below refresh method