Linking digital and paper documents

One or more computer readable media storing information for enabling a computer to perform a process, the process comprising:

• maintaining and storing a set of links between physical documents and digital documents, where the links link multiple physical documents to multiple digital documents, and where the links link multiple digital documents to multiple physical documents;
• automatically identifying various physical documents as they are placed or uncovered on a digital workspace, the digital workspace comprising an area:
• where one or more sensors automatically detect physical documents, where a computing device is capable of displaying graphics generated thereby, and where user interaction with the displayed graphics can be detected;
• displaying with the digital workspace a GUI component comprising one or more user interface controls generated by the computing device, the GUI component being displayed at a location relative to a detected location of one of the physical documents lying on the digital workspace;
• and
• automatically detecting user interaction with the control of the GUI component and in response directing an operation to the paper document comprising either editing a link between the physical document and one of the digital documents, or using a maintained link between the physical document and a digital document to perform an operation on the digital document.

A method of managing relations between paper and digital documents using a digital work area, the digital work area comprising an area where graphics can be displayed in proximity to the paper documents, where images of the work area are captured, and where user input can be detected, the method comprising:

• repeatedly capturing images of the digital work area to detect any paper documents on the digital work area, and from the images detecting when one of the paper documents is on the digital work area;
• using an image containing the paper document to determine a first location comprising a location of the paper document and to identify the paper document and a digital document from which the detected paper document was printed;
• and
• as the paper document remains on the digital work area after being identified, displaying on the digital work area a user interface with which a user can interact to invoke operations directed to the digital document and the paper document corresponding to the digital document, wherein the user interface is displayed at a second location computed according to the first location such that that the user interface is displayed in physical proximity to the paper document.