How to export the differences when using compare function?

When you choose Document > Compare documents, do you have Presentation decks, drawings or Illustrations selected? To get the note exported:

1. Click the two yellow post-it icons at the bottom left of your screen (above the paper clip), it will say Comments.
2. Click the two wheel icons at the top left in this window, they will say Options.
3. Choose Summarize Comments.
4. You can select Comments Only and it will build a PDF with these detail differences.

Hi,
Thanks for your answers.
But its not what I want. When I choose Document>Compare Documents, I selected scanned documents. Because if I select first two options, one window will popup and says the documents are too complex for the selected mode please select scanned documents.The files I compared only have one page respectively, and in comment it says This image was replaced
(click to see the old and difference images), and whole page is marked as replace color. When clicking, I do see the old and difference images which I want to export/save. But once your mouse moves, the images shown will disappear... So I am confusing whether it is possible to export/save/print the images showing the old and differences.

I don't know of a way to extract that image, but you can look in the Compare pane. There are 2 halves, New at the top and Old at the bottom. You can double-click on old to open it in a new window.