variable Panels image page element
First install Fieldable Panels Panes module. This module allows you to create different fields for Panels pane. Then go to admin/structure/fieldable-panels-panes, Click on Manage Fields of Panes Pane



Add an image field, It is going to be like this



Now click on Add Entity tab and create a new entity. You must also create a Category in Reusability, This Category will be displayed in the Panels Content menu, I called it My own Panels Pane



Now save it.

If you open a Panel and click on Add content the My own Panels Pane is available, click on it and select the content you created.



From the list of Panels Pane in Fieldable Panels Pane there is a direct link to edit this image. I mean this (for testing I created 3 entities ):



Now you can easily edit the image and use it's direct link.