You can use the xpath() function to get a list of all of the Outline boxes in your output,
oBoxList = (Report( biv ) << xpath( "//OutlineBox" ))
Then you can loop across the list of Outline Boxes and then use the message << Get Picture to convert the Outline Box to an image and then using the Save Image message to save the image to a file.
See the Scripting Index for descriptions and examples of the xpath, Get Picture and Save Image
Jim