ImageGear provides two functions for examining the contents of the clipboard:

• IG_clipboard_paste_available_ex() lets you know whether there is an image in the system clipboard. It is recommended that you always call this function before pasting from the clipboard, and also before calling IG_clipboard_dimensions(). This function returns an AT_BOOL value, where TRUE means that there is a paste-able image in the clipboard.
• IG_clipboard_dimensions() returns three values to you: the width of the image (in pixels), the height of the image (in pixels), and the number of bits per pixel of the image on the clipboard. Using these values, you can determine whether or not the image dimensions are appropriate for your purposes.