private void solutionCToolStripMenuItem_Click(object sender, EventArgs e)
{
if (img == null) // verify if the image is already opened
{
return;
}
Cursor = Cursors.WaitCursor; // clock cursor
int size = 0;
//copy Undo Image
imgUndo = img.Copy();
ImageClass.Mean_solutionC(img, imgCopy, size);
ImageViewer.Image = img.Bitmap;
ImageViewer.Refresh(); // refresh image on the screen
Cursor = Cursors.Default; // normal cursor
}