Abstract:
A method of determining document characteristics prior to processing the document in a document scanner ( 10 ) includes capturing an input image of documents in an input tray ( 20 ); transmitting the images to a processor ( 65 ); determining characteristics of the documents; and processing the document based on the characteristics.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    Reference is made to commonly-assigned copending U.S. patent application Ser. No. ______ (Attorney Docket No. 96320/NAB), filed herewith, entitled A DOCUMENT SCANNER, by Schaertel et al.; the disclosure of which is incorporated herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to extracting properties of the document fed to a scanner from an input tray, before the document passes scanning cameras on a transport path. 
       BACKGROUND OF THE INVENTION 
       [0003]    A document scanner moves a document through a transport path and creates an image of the document as it moves. The processor memory for the document scanner must have preset document characteristics and the operator must select functions and features to accommodate the specific requirements for a particular document. Alternately, the scanner may default to less efficient settings that will process all documents since scanners are not typically programmed with specific requirements on a document-by-document basis. 
         [0004]    The preset characteristics, features, and functions are a product of document characteristics, such as size, weight, texture, and specific application requirements such as resolution, imaging mode; for example color, simplex, or duplex. In a document scanner, the documents to be scanned may vary by size, weight, color content, physical condition, or other characteristics, which may require different scanner features to be enabled or operator actions to be employed, for the most optimal and efficient mode of operation. Prior knowledge of these many different document attributes can enable the proper selection of scanner features to improve the efficiency of the scanning process or enable other features which may provide specific applications required by a particular type, style, or size of document. 
         [0005]    Prior knowledge of the documents physical condition can also prompt immediate action from the operator to protect the document or scanner or allow other features within the scanner to perform more reliably. There is a need, therefore, for detection of document characteristics prior to the document entering transport path. 
       SUMMARY OF THE INVENTION 
       [0006]    Briefly, according to one aspect of the present invention a method of determining document characteristics prior to processing the document in a document scanner includes capturing an input image of documents in an input tray; transmitting the images to a processor; determining characteristics of the documents; and processing the document based on the characteristics. 
         [0007]    The invention and its objects and advantages will become more apparent in the detailed description of the preferred embodiment presented below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a cross-section view from the side of a document scanner which illustrates the various parts of the scanner related to the present invention. 
           [0009]      FIG. 2  is a perspective view of the scanner and illustrates various types of documents. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0010]    The present invention will be directed in particular to elements forming part of, or in cooperation more directly with the apparatus in accordance with the present invention. It is to be understood that elements not specifically shown or described may take various forms well known to those skilled in the art. 
         [0011]      FIG. 1  is a side cross-sectional view of a document scanner  10 . The illustration shows the input tray  20  and input tray camera or image capture device  30 . A typical scanner also has a transport mechanism for moving documents through the scanner and an output tray for collecting documents as well as other components that makeup a document scanner. 
         [0012]    As shown in  FIG. 1 , documents  11  are first placed in the input tray  20  of the scanner. Imaging capture device  30  captures an image of the top document on the stack of documents  11 . The document image is captured both statically and dynamically as it begins to move forward into the scanner by the feed roller  40  and separation roller  41 . As frames of image data are captured, they are transmitted to be processed by an image processor shown schematically as image processing block  60 . 
         [0013]    The image processing block  60  processes the image data, to determine document characteristics such as document content, document condition, the desired information to be extracted and saved from the document. These characteristics will enable a particular feature or operation of the scanner based on the document content or condition. The document is processed based on the document characteristics. 
         [0014]    Some of the document characteristics that are important in processing the document is the document length  70  or width  80  shown in  FIG. 2 . If a short document is detected the master image buffer (not shown) size is reduced. If a short document is detected the feed roller  40  may also be stopped to prevent jams. For a longer document, the feed roller continues to run which will reduce feed roller wear. 
         [0015]    Another scanner feature related to length and width includes sorting the document on exit from the scanner. For example, if the document is a check  90 . The document may also be checked for compatibility with the scanner. Controlled output stacking  100  shown in  FIG. 1  may be adjusted for higher throughput, or a document gap  110  may be adjusted according to document length. 
         [0016]    An important document characteristic is orientation. Detection of the document orientation as portrait or landscape, relative to the direction of document travel, will be used to improve the performance of the auto orientation feature. Using document width or location of the document in the input tray  20 , is used to improve the document locate function. 
         [0017]    Color or lack thereof within a document will be determined to set the appropriate color mode for image capture. Stick on labels  140  are detected based on color. The results are used to disable ultrasonic sensing in the area of the label. 
         [0018]    Content within the document will be used for line or form detection. This enables the processor  65  to determine whether to capture the image or not and what processing may be required for the image data if captured. Patches and barcodes will be detected and read for the processor to take the appropriate action. Detection of postage stamps  144  or envelopes  142  is used by the processor to adjust scanner operation. 
         [0019]    Document content is processed using optical character recognition (OCR) to detect a predetermined word, detect and interpret magnetic character ink, photographs, text or graphics. The processor then modifies scanner functions, for example, disabling automatic orientation when no text is present. Money may also be detected and counted. 
         [0020]    Document content is also used to detect checks  90  and document resolution. The processor uses this information to adjust scanner functions such as setting the image capture mode. 
         [0021]    A document characteristic useful for scanner processing is a folded corner or torn portion of the document. If those defects are detected the transport will be stopped and the operator will be alerted to this condition. Holes  82  in the document will be detected by the input image capture device  30  and ignored by the machine control function  120  of the scanner. Wrinkles in the document, if detected, causes processor to optimized parameters for sonic  130  or ultrasonic  135  detection. Another detectable characteristic is a staple, paperclip, or rubber band on the document. When detected the processor stops the transport and the operator is alerted of the condition. Tape located on a document may be detected and is a possible indication of a fraudulent document. 
         [0022]    Imaging of the input tray  20  area detects the presence of documents  11  or a batch box  12 . Once documents are detected, the number of documents can be determined. The absence of documents in the input tray will be detected. Orientation or location of the documents detected indicates document skew and location. This information enhances the performance of automatic orientation. The transport may be stopped and the operator altered to conditions that adversely affect operation of the scanner. 
         [0023]    Imaging of the documents  11  will be used to detect dual shadows  150  which may indicate a multi-feed. No movement of the documents may indicate a misfeed. 
         [0024]    Imaging of the input area  13  and processing of the image data will determine characteristics of the input area whereby side guide  15  location can be determined. Correct side guide location will be determined with regard to the documents  11  in the input tray  20 . 
         [0025]    The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the scope of the invention. 
       PARTS LIST 
       [0000]    
       
           10  scanner 
           11  documents 
           12  batch box 
           13  input area 
           15  side guide 
           20  input tray 
           30  imaging capture device 
           40  feed roller 
           41  separation roller 
           60  image processing block 
           65  processor 
           70  document length 
           80  document width 
           82  holes 
           90  check 
           100  controlled output stacking 
           110  document gap 
           120  machine control function 
           130  sonic detection 
           135  ultrasonic detection 
           140  stick on label 
           142  envelope 
           144  postage stamp 
           150  dual shadows