1. A document scanner comprising: an input tray for holding documents; a transport system for moving documents through the scanner along a document transport path within the scanner; at least one document detection sensor located inside the document scanner for detecting documents; an image capture device located along the document transport path within the document scanner for capturing image data for a document; an image processor for determining characteristics of the document based on the image data; and wherein the processor merges the determined characteristics of the document with data from the at least one document detection sensor and excludes data from the at least one document detection sensor which conflicts with image data.