COPIER APPARATUS AND METHOD WITH FLEXIBLE SOURCE DOCUMENT ENTRY SCANNING IN AN IMAGE OVERLAY MODE

A copier apparatus and method includes a scanning station for electronically scanning a set of document sheets to be copied as a copy job. The scanning station includes a platen for supporting a document sheet to be scanned in a first mode wherein the document sheet is manually positioned on the platen by an operator. This document sheet serves as a master and the image thereon is used for copying onto copies made of other document sheets in the set. The scanning station further provides for scanning of the document sheets in a second mode wherein document sheets are automatically fed. A controller automatically actuates the scanning station for scanning a document sheet in the first mode and also actuates a feeder for automatically feeding document sheets to the scanning station for scanning document sheets in the second mode. A memory stores image data of the master document sheet and this image data is logically combined with image data of each of at least plural of the document sheets scanned in the second mode. A marking engine produces one or more collated copy sets of the set of document sheets with each of at least two pages of the copy set being a combination of an image on the document sheet scanned in the first mode and an image of a document sheet scanned in said second mode. The memory stores two sets of image data for the master. A first of these two sets is stored in a first part of the memory and is used for logically combining with image data of document sheets scanned in the second mode and a second is used for replicating a set of the master image data for storage in the first part of the memory after the logically combined image data is read out. This allows for only one platen scan of the master while the image data thereof can be combined with plural different document sheets.