A method of digitally processing images by means of a printing system (1A, 1B, 1C) comprising at least one input holder (2A, 3A, 2B, 3B, 3C) for types of media to be printed upon, a user interface (5A, 5B, 5C) provided with operating means and a display, and a print controller (4A, 4B, 4C) comprising storage and for controlling a print job queue comprising at least one print job scheduled to be printed by the printing system (1A, 1B, 1C), the method comprising the steps of for each type of media present in the at least one input holder: - determining a first amount of the type of media present in the at least one input holder, - determining a second amount (332, 336, 432) of the type of media that is intended to be used by print jobs in the print job queue, - determining a positive surplus amount (333, 337, 433) of the type of media based on the determined first amount and the determined second amount, - storing the positive surplus amount in the storage of the print controller, and - displaying the positive surplus amount on the display of the user interface, wherein the printing system is connected to a network to which another printing system is connected and the method comprises the steps of - receiving via the network a notification from the other printing system that there is a shortage of a third amount of a certain media type with respect to print jobs intended to be printed by means of the other printing system, - comparing the third amount of the certain media type with the positive surplus amount of the same media type whether or not being present in the printing system, and - submitting information about the positive surplus amount to the other printing system via the network. the method comprising the steps of for each type of media present in the at least one input holder: - determining a first amount of the type of media present in the at least one input holder, - determining a second amount (332, 336, 432) of the type of media that is intended to be used by print jobs in the print job queue, - determining a positive surplus amount (333, 337, 433) of the type of media based on the determined first amount and the determined second amount, - storing the positive surplus amount in the storage of the print controller, and - displaying the positive surplus amount on the display of the user interface, - determining a first amount of the type of media present in the at least one input holder, - determining a second amount (332, 336, 432) of the type of media that is intended to be used by print jobs in the print job queue, - determining a positive surplus amount (333, 337, 433) of the type of media based on the determined first amount and the determined second amount, - storing the positive surplus amount in the storage of the print controller, and - displaying the positive surplus amount on the display of the user interface, wherein the printing system is connected to a network to which another printing system is connected and the method comprises the steps of - receiving via the network a notification from the other printing system that there is a shortage of a third amount of a certain media type with respect to print jobs intended to be printed by means of the other printing system, - comparing the third amount of the certain media type with the positive surplus amount of the same media type whether or not being present in the printing system, and - submitting information about the positive surplus amount to the other printing system via the network. - receiving via the network a notification from the other printing system that there is a shortage of a third amount of a certain media type with respect to print jobs intended to be printed by means of the other printing system, - comparing the third amount of the certain media type with the positive surplus amount of the same media type whether or not being present in the printing system, and - submitting information about the positive surplus amount to the other printing system via the network.