Patent Publication Number: US-9898237-B1

Title: System and method of printing using mixed paper sizes

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional of application Ser. No. 15/278,574, filed Sep. 28, 2016, which is incorporated herein by reference. 
    
    
     FIELD 
     This disclosure relates generally to printing technology and, more particularly, to a printer, method, and program stored in non-transitory computer readable medium for printing using mixed paper sizes. 
     BACKGROUND 
     Print jobs may have a mixture of sheet sizes, in particular a mixture letter and legal-sized sheets. Thus, a printer can have trays that store letter- and legal-size printing media. Print jobs may also include print settings in which a user may specify how the print job is to be handled by the printer. For example, the user may specify that printing media from a particular tray be used and/or that the output document be stapled at a particular location. In addition, a print job may include some images that are oriented in portrait mode and others that are oriented in landscape mode. It is desirable for the printer to take into account input sheet sizes, print settings, image orientations, and/or other factors. Also, there is a continuing need to reduce print processing time and/or reduce manual labor in possibly having to rearrange the orientation of sheets in an output document. A reduction in print processing time and manual labor can be particularly important in high volume printing operations, for example. 
     SUMMARY 
     Briefly and in general terms, the present invention is directed to a printer, a computer program embodied in a non-transitory computer readable medium, and a method for printing. 
     In aspects of the invention, a computer program is embodied on a non-transitory computer readable medium having a computer readable program code stored therein for controlling a data processing apparatus capable of communicating with a printer comprising a first tray configured to store letter-sized paper oriented in a long edge feed (LEF) direction, a second tray configured to store letter-sized paper oriented in a short edge feed (SEF) direction, and a third tray configured to store legal-sized paper oriented in the SEF direction. The computer readable program code causes the data processing apparatus to execute a process for submitting a print job to the printer, the process comprising determining whether an auto tray selection has been set for the print job, determining whether a staple mode has been set for the print job, and providing a user notification when it has been determined that both the auto-tray selection has been set for the print job and the staple mode has not been set for the print job, the user notification indicating that letter-sized paper oriented in the SEF direction and obtained from the second tray may be used by the printer for the print job. 
     The features and advantages of the invention will be more readily understood from the following detailed description which should be read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of an exemplary printer. 
         FIG. 2  is a schematic internal view of the printer of  FIG. 1 . 
         FIG. 3  is a schematic plan view of exemplary first, second, and third trays of the printer of  FIG. 1 . 
         FIGS. 4 and 5  are schematic plan views showing walls within any one of the trays of  FIG. 3 . 
         FIG. 6  is a block diagram showing a system having the printer of  FIG. 1  in communication with an exemplary host data processing apparatus, such as a host computer. 
         FIG. 7  is diagram showing an exemplary print setting window. 
         FIG. 8  is a table showing exemplary processes for tray selection based in part on input sheet size. 
         FIG. 9  is a diagram showing an exemplary mixture of input sheet sizes. 
         FIG. 10  is a diagram showing an exemplary output document in which long edges of sheets are misaligned according to Example 6 of  FIG. 8 . 
         FIG. 11  is a diagram showing an exemplary output document in which long edges of sheets are aligned according to Example 7 of  FIG. 8 . 
         FIG. 12  is a table showing exemplary image rotation processes that are possible for Example 7 of  FIG. 8 . 
         FIGS. 13A-13C  are flow diagrams showing an exemplary process that may be performed by a printer. 
         FIG. 14  is a flow diagram showing a modification of  FIG. 13A . 
         FIG. 15  is a diagram showing an exemplary query window that may be implemented for the process of  FIG. 14 . 
         FIG. 16  is a flow diagram showing an exemplary process that may be performed by a host computer or other data processing apparatus in communication with a printer. 
         FIG. 17  is a diagram showing an exemplary query window that may be implemented for the process of  FIG. 16 . 
         FIG. 18  is a flow diagram showing a modification of  FIG. 14 . 
     
    
    
     DETAILED DESCRIPTION 
     As used herein, the term “printer” encompasses a variety of machines capable of forming an image on a paper sheet made of fibrous material, a transparent sheet made of acetate, or other type of printing media. Examples of printers include, without limitation, copying machines wherein physical documents are optically scanned to capture images on the documents so that the images can be duplicated on printing media; laser, inkjet, and other types of printing machines wherein image data of an electronic file, such as a file from a word processing, graphics or other type of computer program, is processed for printing onto printing media; and a multi-function peripheral (MFP) device having the combined functions of a copying machine and printing machine. 
     As used herein, the term “image” encompasses any one or a combination of photographs, pictures, illustrations, alphanumeric and linguistic characters, symbols, and other graphical representations. 
     Referring now in more detail to the exemplary drawings for purposes of illustrating aspects of the invention, wherein like reference numerals designate corresponding or like elements among the several views, there is shown in  FIG. 1  exemplary printer  10  in the form of an MFP device. It is to be understood that the invention may be embodied in or make use of another type of MFP device, copy machine, or printing machine. 
     Printer  10  is capable of handling a print job, which can be one that was sent to printer  10  or be a copy job that involves duplicating a physical document placed by a user on printer  10 . A print job can be sent by a user to printer  10  from a data processing apparatus (a host computer, for example) for the purpose of printing an electronic document defined in the print job. As used herein, the term “print job” encompasses any of a print job that was sent to printer  10  and a copy job. 
     As shown in  FIG. 1 , printer  10  comprises display/control panel  11 , image reading assembly  12  for copy jobs, and a plurality of trays  92 ,  94 ,  96  which can be pulled out of printer housing  98 . The trays hold stacks of printing media of different sizes and orientations. Printing media is usually in the form of blank sheets of paper. 
     As shown in  FIG. 2 , printer  10  further comprises image writing assembly  14 , image forming assembly  16 , printing media conveyance assembly  18 , printing media ejection assembly  20  (at the left side of the figure), and printing media reversing assembly  22 . These assemblies are described in turn below. 
     Image reading assembly  12  reads optical information of one or more images on document S. Document S is a physical document a user has placed on printer  10 . Reading is performed by illuminating document S with light and converting the optical information into electrical or digital information. For example, document S may be placed on transparent platen  30  such that the image on document S faces down on platen  30 . Optical scanning is performed as follows. Light source  32  projects light on the image-bearing surface of document S. The light arriving at the image-bearing surface of document S is reflected onto mirror  34 . The light arriving at mirror  34  includes information about the image on document S. Light source  32  and mirror  34  are configured to move along platen  30 , such as by a rail and motor, so that the entire image-bearing surface of document S can be optically scanned while document S remains stationary on platen  30 . 
     Document S can be a stack of sheets of paper. To handle a stack of sheets, printer  10  comprises sheet feeding assembly  40  which separates an individual sheet from the stack of sheets placed on sheet input stand  42 . Adjacent to sheet input stand  42  are a series of rollers  44 ,  46  that pull an individual sheet from the stack of sheets and convey the individual sheet across slit glass  48 . Unlike light source  32  and mirror  34 , light source  50  and mirror  52  are fixed in position below the slit glass  48 . This arrangement allows for continuous optical scanning of the image-bearing surfaces of the sheets as the sheets move across slit glass  48 . Each sheet is ejected to sheet ejection stand  43  after the sheet has been optically scanned. 
     Document S may also have images on both sides of the sheets, so printer  10  may be configured to optically scan both sides of each sheet if desired. The sheet is taken from sheet input stand  42  by rollers  44 ,  46 , which convey the sheet to slit glass  48  where one side of the sheet is optically scanned by light source  50  and mirror  52 . After one side has been completely scanned, the sheet is fed out by roller  54  in the direction of arrow  56 . Before reaching the end of the sheet, roller  54  reverses direction so that the sheet travels in the direction of arrow  57  and is taken up by roller  46  in such a way that the other side of the sheet is passed across slit glass  48 , so the other side of the sheet is optically scanned. Thereafter, the sheet is ejected to sheet ejection stand  43 . 
     Optical information obtained from light emitted from light sources  32  or  50  and reflected from the image-bearing surface of a sheet is captured by mirrors  34  or  52 . The reflected light is guided by additional mirrors  35  or  53  through image forming optical system  58  to image pick-up device  59 , which is configured to convert incoming photons to electron charges. Exemplary image pick-up devices include without limitation charged-coupled device (CCD) image sensors and complementary metal-oxide-semiconductor active-pixel sensors (CMOS APS). For example, a CCD image sensor may have a photoelectric surface on which a plurality of pixels is arranged, with each pixel represented by a capacitor configured for photoelectric conversion of photons. The optical information defining the image reflected from the image-bearing surface of the sheet is received by the pixels, which convert the optical information into electrical information which can then be read out from the CCD image sensor. The electrical information from the CCD image sensor is processed by the printer processor to form image data. Alternatively, image data may be obtained from a print job that is sent to printer  10  by a data processing apparatus, such as a host computer. 
     Image writing assembly  14  generates electrostatic latent images based on image data obtained from image reading assembly  12  or a print job. Image writing assembly  14  comprises a laser emitter and various mirrors controlled by motors for guiding laser beam B to photoreceptor drum  60 . The obtained image data are used to control the laser emitter and motor  61  which rotates polygon mirror  62 . Laser beam B is reflected from polygon mirror  62  and another mirror  63  onto photoreceptor drum  60 . Mirror  63  scans laser beam B along the axis of photoreceptor drum  60  to produce an electrostatic latent image on the drum surface that matches the optically scanned image from the sheet of document S or matches an image defined by a print job sent to printer  10 . 
     Before the electrostatic latent image is formed on drum  60 , the entire surface of drum  60  is uniformly charged by charging assembly  64 . Next, the electrostatic charge on portions of the surface of drum  60  is neutralized by laser beam B which is scanned onto the surface of drum  60  according to the image data obtained from image reading assembly  12  or a print job sent to printer  10 . The neutralized areas of drum  60  form the electrostatic latent image. 
     Still referring to  FIG. 2 , image forming assembly  16  uses the electrostatic latent image on photoreceptor drum  60  to form a matching toner image on printing media P taken from one of trays  92 ,  94 ,  96 . Developing assembly  65  delivers charged toner particles to photoreceptor drum  60 . The toner particles adhere only to the electrostatic latent image. That is, the toner particles adhere only to areas of the surface of drum  60  where laser beam B has neutralized the electrostatic charge previously applied by charging assembly  64 . Image forming assembly  16  also includes various rollers  66  that convey printing media P to drum  60 . The toner particles on drum  60  are transferred by transfer assembly  67  onto printing media P. The toner particles adhere to printing media P so that printing media P now carries a toner image that matches the optically scanned image from the sheet of document S or matches an image defined by a print job sent to printer  10 . 
     Separation assembly  68  separates printing media P from photoreceptor drum  60 . Separation assembly  68  may include a rotating roller that pulls printing media P from drum  60 . Next, cleaning assembly  70 , which may include a flexible scraper blade, removes any residual toner on drum  60  to create a cleaned surface so that uniform charging of drum  60  by charging assembly  64  can be repeated. 
     After printing media P is separated from photoreceptor drum  60 , printing media P is conveyed by conveyance mechanism  72  to fixing assembly  74 . Conveyance mechanism  72  includes a plurality of rollers which rotate a looped belt. Fixing assembly  74  includes rollers  76  configured to apply pressure and heat to printing media P. The pressure and heat fixes the toner image onto printing media P. Thereafter, printing media P is ejected by rollers  78  of ejection assembly  20  out of housing  98 . Printing media P is ejected out of output slot  81  and onto output tray  82  attached to housing  98 . Stapler  83  is located at output slot  81  and is configured to apply a staple according to print settings specified by the user. 
     Transfer of a toner image from photoreceptor drum  60  onto printing media P can be performed for both sides of printing media P. After the toner image is fixed on one side of printing media P, printing media P is conveyed to printing media reversing assembly  22  which includes pivoting guide device  84  that switches the conveying path of printing media P between the printing media reversing assembly  22  and printing media ejection assembly  20 . When guide device  84  is in a reversing position, printing media P is conveyed downward as indicated by arrow  85 , instead of be conveyed through output slot  81 . Printing media P is conveyed by rollers  86  to reversing area  88 . After printing media P has moved into reversing area  88  by a predetermined amounted, rollers  86  rotate in the opposite direction to convey printing media P in a reverse direction indicated by arrow  89 . Printing media P travels through reverse conveyance path  91  and arrives at the upstream side of drum  60  once again. This time, the opposite side of printing media P faces drum  60  and is subjected to toner image transfer and fixing in the same manner previously described. 
     Still referring to  FIG. 2 , trays  92 ,  94 ,  96  are configured to store printing media P of different sizes and orientations. Printing media conveyance assembly  18  includes rollers  102  that convey printing media P from trays  92 ,  94 ,  96  to photoreceptor drum  60 . Each of trays  92 ,  94 ,  96  includes floor  104  that raises printing media P into contact with rollers  102 . 
     Exemplary sizes for printing media P include letter-sized paper having dimensions of 8.5 inches×11 inches (21.6 cm×27.9 cm) and legal-sized paper having dimensions of 8.5 inches×14 inches (21.6 cm×35.6 cm). The possible orientations are a long edge feed (LEF) direction and a short edge feed (SEF) direction. The LEF and SEF directions refer to the orientation of printing media P as it is fed through printer  10 . 
     For printing media P that is letter-sized paper, orientation in the LEF direction means that the paper sheet is oriented such that its long edge (i.e., the 11 inch or 27.9 cm edge) is fed first or leads the way along conveying path  90  to photoreceptor drum  60 . The long edge is perpendicular to the feed direction along conveying path  90 . 
     For letter-sized and legal-sized papers, orientation in the SEF direction means that the paper sheet is oriented such that its short edge (i.e., the 8.5 inch or 21.6 cm edge) is fed first or leads the way along conveying path  90  to photoreceptor drum  60 . The short edge is perpendicular to the feed direction along conveying path  90 . 
     As shown in  FIG. 3 , first tray  92  is configured to store a stack of letter-sized paper  93  oriented in the LEF direction. Second tray  94  is configured to store a stack of legal-sized paper  95  oriented in the SEF direction. Third tray  96  is configured to store a stack of letter-sized paper  97  oriented in the SEF direction. 
     The designation of trays as “first,” “second,” and “third” is arbitrary, and the order and arrangement of the trays may be modified. Referring again to  FIG. 1 , first tray  92  may instead be located in the middle position within printer housing  98 , and second tray  94  may be located below or above first tray  92 . As a further example, first tray  92  may instead be located at the bottom position within printer housing  98 , and second tray  94  may be located at the middle or top position. Other arrangements for the trays are possible. 
     In  FIG. 4 , one or more of trays  92 ,  94 ,  96  may have walls  99 ,  100  that are fixed and not adjustable in position, such that the tray is configured to hold only one size of printing media P in one particular orientation. In this context, the tray in  FIG. 4  can be any one of trays  92 ,  94 ,  96  and be configured to hold only letter-sized paper oriented only in the LEF direction. 
     Alternatively, with reference to  FIGS. 4 and 5 , one or more of trays  92 ,  94 ,  96  may have walls  99 ,  100  that are movable on a rail and can be fixed at a position desired by the user. In this context, walls  99 ,  100  can be moved from the positions shown in  FIG. 4  to the positions shown in  FIG. 5 . Movable walls  99 ,  100  allow the tray is be adjusted to hold a desired paper size in a desired orientation. For example, walls  99 ,  100  of the tray may be adjusted so that the tray is configured to store letter-sized paper oriented in the LEF direction as shown in  FIG. 4 . Later, walls  99 ,  100  may be adjusted so that the tray is configured to store letter-sized paper oriented in the SEF direction as shown in  FIG. 5 . 
     Referring now to  FIG. 6 , system  108  comprises printer  10  in communication with host computer  110 . Host computer  110  may be a computer workstation, personal computer, laptop computer, tablet, smartphone, or other data processing apparatus. Host computer  110  may include printer driver  111 , which is software that receives data and converts the received data to a format that can be used by printer  10  for printing. Optionally, host computer  110  may be running a word processing, graphics, or other computer program which generates the data that is received and converted by printer driver  111 . The computer program may have a print function that utilizes printer driver  111 . 
     Communication between printer  10  and host computer  110  is achieved through network  120  that may include wired and wireless communication means known in the art. For example, network  120  may comprise any one or a combination of a local area network (LAN), wide area network (WAN), portions of the Internet, and telephone communication carriers. Network  120  is used by host computer  110  to send a print job to printer  10 . Printer  10  may use network  120  to send computer  110  information about the status of the print job. 
     As shown in  FIG. 6 , host computer  110  includes elements interconnected by communication bus  112 . The elements include central processing unit (CPU)  113 , memory  114 , input unit  115 , display unit  116 , and network interface (I/F)  117 . 
     CPU  113  includes one or more computer processors having circuitry that executes instructions of computer programs, such as a printer driver for use with printer  10 . CPU  113 , which can be referred to as a “host processor,” is configured to perform various methods and processes described herein by executing instructions. Instructions executed by CPU  113  include those required for the process of  FIG. 16 . 
     Memory  114  includes one or a combination of non-volatile and volatile memory storage devices. Exemplary storage devices include without limitation random-access memory (RAM) modules and read-only memory (ROM) modules, as well as optical, magnetic, and solid-state flash storage devices. Printer driver  111  is stored in memory  114 . Instructions required for the process of  FIG. 16  may also be stored in memory  114 . Input unit  115  allows the user to enter data and interact with host computer  110 . 
     Input unit  115  includes one or a combination of a keypad with buttons and a touch-sensitive screen which are configured to receive user input, such as print settings for a print job. Display unit  116  is configured to display print settings and can be a liquid crystal display or other type of electronic visual display device. Network I/F  117  includes circuitry configured to allow data transfer to and from printer  10  via network  120 . 
     Still referring to  FIG. 6 , various elements of printer  10  are interconnected by communication bus  210 . The elements include network interface (I/F)  202 , central processing unit (CPU)  203 , memory  204 , input unit  205 , display unit  206 , image reading assembly  12 , image writing assembly  14 , image forming assembly  16 , printing media conveyance assembly  18 , stapler  83 , and printing media trays  92 ,  94 ,  96 . 
     Network I/F  202  includes circuitry configured to allow data transfer to and from host computer  110  via network  120 . CPU  203  includes one or more computer processors having circuitry that executes instructions. CPU  203 , also referred to as a “printer processor,” is configured to perform various methods and processes described herein by executing instructions. Instructions executed by CPU  203  include those required to operate, control, and/or coordinate the various assemblies and components of printer  10  described above. Such instructions are collectively referred to as printer controller program  207 . 
     Memory  204  includes one or a combination of non-volatile and volatile memory storage devices. Exemplary storage devices include without limitation RAM modules and ROM modules, as well as optical, magnetic, and solid-state flash storage devices. Memory  204  may store printer controller program  207  and/or others which when executed, causes printer  10  to perform the methods and processes described herein. 
     Input unit  205  and display unit  206  may form parts of display/control panel  11  ( FIG. 1 ). Input unit  205  includes one or a combination of a keypad with buttons and a touch-sensitive screen which are configured to receive user input, such as print settings for a copy job. Display unit  206  is configured to display print settings and can be a liquid crystal display or other type of electronic visual display device. When input unit  205  includes a touch-sensitive screen, the touch sensitive screen may be layered over display unit  206  to facilitate user selection of print settings. 
     Stapler  83  is coupled to CPU  203  to enable stapling of an output document based to print settings. Paper trays  92 ,  94 ,  96  may include sensors, such as mechanical arms or optical switches, that detect the printing media size and/or orientation within each tray. Such sensors may be needed if walls  99 ,  100  of the tray are adjustable. Additionally or alternatively, the sensors may detect whether the tray is empty or in a pulled-out position. Information from the sensors is provided to CPU  203  to allow for proper selection of trays. 
       FIG. 7  shows an exemplary print setting window  122  that allows the user to specify print settings for a print job. Window  122  includes various menus to allow the user to specify the tray from which printing media will be taken and to specify whether the user desires stapling to be performed on the printing media as part of a finishing process. By selecting one of the available trays, the user may require printing of a print job to be performed using a specific tray containing a known printing media size and orientation. By selecting “Auto” (auto tray selection), the user allows printer  10  to automatically select the printing media size and orientation that is most appropriate for the print job. 
     Printer  10  may be designed to minimize print processing time, as will be discussed later, by preferentially selecting the long edge of printing media P to be the feeding edge (i.e., the edge that leads the way along conveying path  90 ) when a particular printing media size is stored in both SEF and LEF orientations. Thus, when the “Auto” (auto tray selection) has been chosen in  FIG. 7  and letter-sized paper is stored in the LEF direction in first tray  92  and stored in the SEF direction in third tray  96 , printer  10  will use printing media P obtained from first tray  92  for printing a letter-sized image. Alternatively, printer  10  will obtain printing media P from third tray  96  if the user has chosen “Tray  3 ” in  FIG. 7 . 
     Print setting window  122  may include a variety of graphical user interface (GUI) elements to allow selection of print settings. For example, a selection check box  124  may be activated by the user to specify that stapling is desired. Selection arrow-buttons  126  may be activated by the user to select a printing media tray setting and staple mode. A staple mode refers to the position and, optionally, the number of staples on an output document. Inclusion of a staple mode in a print setting means that stapling is desired by the user. An OK button  128  may be activated by the user to apply the selected print settings. 
     Printer driver  111  executed by CPU  113  of host computer  110  may cause print setting window  122  to be displayed on display unit  116  of host computer  110 . For example, when a user wishes to print an image from host computer  110 , print setting window  122  will allow the user to apply print settings for the print job that will be sent from host computer  110  to printer  10 . 
     Software executed by CPU  203  of printer  10  may cause print setting window  122  to be displayed on display unit  206  of printer  10 . For example, when a user wishes to copy a document which has been placed on sheet input tray  42  or platen  30 , print setting window  122  will allow the user to establish print settings for creating the output document that will provided on output tray  82 . 
     Printer  10  is configured to select the printing media having the appropriate size from a corresponding tray  92 ,  94 , or  96 . This is referred to as tray selection. Printer  10  may use various factors for tray selection. An exemplary selection factor is minimization of print processing time. To minimize print processing time, printer  10  may default to selecting paper oriented in the LEF direction in some situations. With paper oriented in the LEF direction, the linear amount of paper, as measured along conveying path  90 , that must pass across photoreceptor drum  60  is based on the short edge of the paper. Thus, the linear amount will be reduced as compared to paper oriented in the SEF direction. With this reduction, it may be possible for more sheets of paper to be printed within a given amount of time. Other tray selection factors involve print settings as discussed in the following examples. 
       FIG. 8  shows examples of possible tray selection processes for print jobs performed by printer  10  according to the factors mentioned above. The input sheet size refers the sheet size that is provided to printer  10 . For a copy job, input sheet size refers to the physical sheet sizes of the pages of document S that are fed through printer  10 . For a print job sent from host computer  110 , input sheet size refers to the detected sheet sizes of images defined in the print job for an electronic document. “Letter” means that the input sheet size for the entire print job is exclusively letter size having dimensions of 8.5 inches×11 inches (21.6 cm×27.9 cm). “Legal” means that the input sheet size for the entire print job is exclusively legal size having dimensions of 8.5 inches×14 inches (21.6 cm×35.6 cm). “Legal and Letter” means that the input sheet sizes for the entire print job are a mixture of letter size and legal size. The printer output could be provided to the user with the front surface of the sheets facing down on output tray  82  ( FIG. 2 ). Thus, the printer output illustrated in the far-right column of  FIG. 8  shows the resulting document facing down, as symbolized by the reversed letter B. Stapler  83  is shown in the far-right column to indicate the edge of the output document that is located next to printer output slot  81 . 
     In Example 1, the entire print job is letter size and the user wants the printer output to be stapled on the left corner. Printer  10  selects letter-sized printing media P oriented in the LEF direction which is contained in first tray  92 . This selection allows the left corner to be located by stapler  83  at output slot  81  ( FIG. 2 ). Printer  10  selects first tray  92  even when the short edge of document sheets are fed into printer  10  for a copy job. This tray selection process with image rotation (discussed later) allows staple  106  to be placed on the top left corner as required by the staple mode in the print setting. 
     In Example 2, the entire print job is letter size, and the user has selected auto tray selection and no stapling. With auto tray selection, the user has allowed printer  10  to automatically select the printing media size and orientation deemed most appropriate by the printer for the print job. Printer  10  selects letter-sized printing media P oriented in the LEF direction which is contained in first tray  92 . This selection is made to try to minimize print processing time, as previously discussed. Even when the short edges of document sheets are fed into printer  10  for a copy job, printer  10  selects first tray  92  to try to minimize print processing time. 
     In Example 3, the entire print job is legal size, and the user wants the printer output to be stapled on the left corner. Legal-sized printing media P is stored only in the SEF direction within in printer  10 , specifically in second tray  94 . Therefore, printer  10  selects legal-sized printing media P oriented in the SEF direction contained in second tray  94 . This tray selection process with image rotation (discussed later) allows staple  106  to be placed on the top left corner as required by the staple mode in the print setting. 
     In Example 4, the entire print job is legal size, and the user has selected auto tray selection and no stapling. Printer  10  selects legal-sized printing media P oriented in the SEF direction contained in second tray  94  since this is the only choice. 
     In Example 5, the print job is a mix of letter and legal size, and the user wants the printer output to be stapled on the left corner. This situation may arise, for example, when a job is related to a real estate escrow file, which will sometimes include a mixture of paper sizes. For example, pages 1-4 and 6 could be legal size and pages 5 and 7 could be letter size as shown in  FIG. 9 . For legal size pages, printer  10  selects second tray  94  since this is the only choice. For letter size pages, printer  10  selects letter-sized printing media P oriented in the SEF direction so that the top left corner of all output sheets are aligned for stapling. 
     In Example 6, the print job is a mix of letter and legal size, and the user has selected auto tray selection and no stapling. For legal size pages, printer  10  selects second tray  94  since this is the only choice. For letter size pages, printer  10  could select letter-sized printing media P oriented in the LEF direction which is contained in first tray  92 . This selection could be made to try to minimize print processing time, but the resulting printer output would have pages having long edges oriented vertically mixed with pages having long edges oriented horizontally. For clarity, the pages of the output document are shown separately in  FIG. 10 . (The reversed letter B symbolizes that the output document is facing down, as may be provided to the user on output tray  82  of  FIG. 2 .) This mixture of orientations can make subsequent filing of the output document difficult, and may require the user to manually rearrange the pages so that all the long edges are aligned. 
     Example 7 addresses the difficulties discussed with Example 6. In Example 7, again the print job is a mix of letter and legal size, and the user has selected auto tray selection and no stapling. For legal size pages, printer  10  selects second tray  94  since this is the only choice. For letter size pages, printer  10  selects letter-sized printing media P oriented in the SEF direction which is contained in third tray  96 . This selection is made to avoid the mixture of orientations in the output document. The resulting printer output would have the long edges of all pages aligned. For clarity, the pages of the output document are shown separately in  FIG. 11 . (The reversed letter B symbolizes that the output document is facing down, as may be provided to the user on output tray  82  of  FIG. 2 .) There is no need for the user to manually rearrange the pages, which can save a significant amount of time such as in high volume printing operations. Compared to Example 6, Example 7 could be viewed as placing greater priority on avoiding the mixture of orientations in the output document than on trying to minimizing print processing time. 
     As will be discussed in detail below, rotation of image data can be performed so that printer  10  can handle various print settings. On one hand, it may be desirable to avoid image rotation for the most common situations since image rotation requires the use of greater computing resources and, thus, may adversely affect printing throughput. On the other hand, using printing media oriented in the LEF direction is physically efficient in that it reduces the linear amount of paper, as measured along conveying path  90 , that must travel across photoreceptor drum  60 . To help minimize print processing time, printer  10  can be optimized for the most common input image orientation and for the most physically efficient printing media orientation. That is, printer  10  can be configured in such a way that rotation of image data is not required for a situation in which the input image is oriented in portrait mode and a matching toner image is to be formed on printing media P oriented in the LEF direction. However, in Example 7, printer  10  uses printing media P oriented in the SEF direction, which means that rotation of the image data may have to be performed in some situations. 
     Referring again to  FIG. 9 , the letter B symbolizes the image, which in reality can be any one or a combination of a photograph, picture, illustration, string of alphanumeric and linguistic characters, symbol, and other graphical representation. The orientation of the letter B relative to the edges of the paper sheet indicates that the input image is in portrait mode for all pages (letter- and legal-sized) of a print job. Referring now to  FIGS. 8 and 11 , recall that in Example 7 printer  10  has selected trays which provide printing media P oriented in the SEF direction. If printer  10  is configured for no rotation of a portrait mode input image when printing media P is oriented in the LEF direction, then printer  10  must rotate a portrait mode input image when printing media P is oriented in the SEF direction. In such a case, CPU  203  of printer  10  may apply a rotational transformation algorithm on the image data (corresponding to  FIG. 9 , for example) so that the image data are rotated. Next, the rotated image data are used to form an electrostatic latent image on photoreceptor drum  60  so that a correctly oriented toner image is transferred on printing media P (corresponding to  FIG. 11 , for example). 
     As shown in  FIG. 12 , it is possible for mixed sheet sizes to have input images (also referred to as “image data”) which are not in portrait mode for all pages (letter- and legal-sized) as it was in  FIG. 9 . The image data of mixed sheet size print jobs can be in landscape mode entirely or a mix of portrait and landscape modes.  FIG. 12  illustrates various orientation combinations of first image data for a legal-sized page of the print job and second image data for a letter-sized page of the print job. 
     As used herein with image data, the terms “first” and “second” are arbitrary and do not define the sequential position of pages. The first image data could be for a legal-sized page (for example, page 1 of a document) and the second image data could be a subsequent letter-sized page (for example, page 2 of the document), as shown in  FIG. 12 . Alternatively, the first image data could be for a legal-sized page (for example, page 15 of a document) and the second image data could be for a previous letter-sized page (for example, page 13 of the document). 
     The phrase “orientation combination” refers to orientations based on portrait mode and landscape mode. Portrait mode is when the top-to-bottom direction of the image data is parallel to the long edge of the page, and the left-to-right direction of the image data is parallel to the short edge of the page. Landscape mode is when the top-to-bottom direction of the image data is parallel to the short edge of the page, and the left-to-right direction of the image data is parallel to the long edge of the page. For example, image data are in portrait mode when the image data contains English text predominantly having a left-to-right direction that is parallel to the short edge of the page. As a further example, image data are in portrait mode when the image data contains an architectural drawing having a top-to-bottom direction that is parallel to the long edge of the page. The orientation combination may be determined by the printer processor from any one or a combination of encoding contained in the print job and performance by the printer processor of an optical character recognition (OCR) process on the image data. 
     In Example 7A of  FIG. 12 , the orientation combination is portrait mode for both first image data for a legal-sized page of the print job and second image data for a letter-sized page of the print job. Example 7A corresponds to the situation previously discussed, in which image data are in portrait mode for all letter- and legal-sized pages of a print job, as shown in  FIG. 9 . As a result, image data are rotated 90 degrees by CPU  203  before being used to form matching images on legal-sized SEF and letter-sized SEF printing media P. This process results in a desirable arrangement in which left edges (see broken lines) of all portrait output images are aligned in the output document when viewed from the front. 
     In Example 7B, the orientation combination is landscape mode for both first image data for a legal-sized page of the print job and second image data for a letter-sized page of the print job. This can be referred to as landscape input to SEF output. As previously discussed, portrait input to LEF output requires no image rotation by default, potentially so that printer  10  is optimized for the most common input image orientation (portrait) and for the most physically efficient printing media orientation (LEF). In the case of portrait input to LEF output, the horizontal (left-to-right) direction in the input image is parallel to the printing media feed direction along conveying path  90 . The same is true in the case of landscape input to SEF output in Example 7B, so no image rotation is required for Example 7B. In addition, this process results in a desirable arrangement in which top edges (see broken lines) of all landscape output images are aligned in the landscape output document when viewed from the front. 
     In Example 7C, the orientation combination is portrait mode for first image data for a legal-sized page of the print job and landscape mode for second image data for a letter-sized page of the print job. The portrait mode image data for a legal-sized page are rotated 90 degrees before being used to form a matching image on legal-sized SEF printing media P, similar to Example 7A. The landscape mode image data for a letter-sized page is handled differently than Example 7B since it is usually desired to have the top edge (see broken line) of the letter-sized landscape output image aligned with the left edge (see broken line) of the legal-sized portrait output image. Thus, landscape mode image data for a letter-sized page are rotated 180 degrees before being used to print on letter-sized SEF printing media P. 
     In Example 7D, the orientation combination is landscape mode for first image data for a legal-sized page of the print job and portrait mode for second image data for a letter-sized page of the print job. It is not necessary to rotate the landscape mode image data for the same reasons given in Example 7B. It is usually desired to have the top edge (see broken line) of the legal-sized landscape output image aligned with the left edge (see broken line) of the letter-sized portrait output image. Thus, portrait mode image data for a letter-sized page are rotated before being used to print on letter-sized SEF printing media P. 
     The rotation determination column of  FIG. 12  is based in part on a default configuration of printer  10  in which portrait input to LEF output requires no image rotation. The default configuration of printer  10  may be different. For example, the default configuration of printer  10  may be such that portrait input to SEF output in Example 7A requires no image rotation, in which case the rotation column for Examples 7B-7C may be altered to provide the desired printer output result. 
       FIGS. 13A-13C  show an exemplary process for printing that may be performed by printer  10  or another printer. At S 300  a printer processor determines whether a print job has been received, such as from a host computer or other data processing apparatus. An exemplary printer processor is CPU  203  of printer  10 . If no print job has been received (S 300 : NO), the printer processor may continue to monitor for receipt of a print job. If a print job has been received (S 300 : YES), the printer processor determines at S 302  whether stapling will, in fact, be performed according to a print setting for the print job. Even if the print setting specifies stapling, stapling will not be performed if, for example, the staple mode requires two staples (referred to as double stapling) spaced apart along a long edge of a legal-sized sheet but printer  10  stores legal-sized printing media P only in the SEF direction. Other situation may occur in which the print setting specifies stapling but printer  10  is unable to perform stapling. 
     If stapling will, in fact, be performed (S 302 : YES), then the printer processor proceeds with printing at S 304  according to the print settings. For example, the printer processor may print the print job of Examples 1, 3, and 5 of  FIG. 8 . If stapling will not be performed (S 302 : NO), then the printer processor determines at S 306  whether auto tray selection has been entered by the user. If auto tray selection has not been entered (S 306 : NO), then the printer processor proceeds with printing at S 304  according to the print settings. If auto tray selection has been entered (S 306 : YES), then the printer processor determines at S 308  whether the print job has a mix of legal and letter sheet sizes. If the input sheet sizes are mixed (S 308 : YES), the process continues to  FIG. 13B . If the input sheet sizes are not mixed (S 308 : NO), the process continues to  FIG. 13C . A difference between  FIGS. 13B and 13C  is the selection of a letter-sized paper oriented in the SEF direction ( FIG. 13B , S 116 ) versus the LEF direction ( FIG. 13C , S 330 ). 
     Referring to  FIG. 13B , after the printer processor has determined that input sheet sizes are mixed, the printer processor determines at S 310  whether image rotation is necessary. The determination at S 310  can be performed according to an orientation combination of first and second image data as described for any one or more of the examples of  FIG. 12 , or it can be performed according to another method. If image rotation is necessary (S 310 : YES), the printer processor proceeds to rotate the image at S 312 , and then determines at S 314  whether the current image is letter-sized. If image rotation is not necessary (S 310 : NO), the printer processor proceeds directly to S 314  to determine whether the current image is letter-sized. If the image is letter-sized (S 314 : YES), the printer processor selects a tray at S 316  that is known contain letter-sized paper oriented in the SEF direction. If the image is not letter-sized (S 314 : NO), the printer processor selects a tray at S 318  that is known contain legal-sized paper. After making the tray selection at S 316  or S 318 , the printer processor causes the image to be printed at S 320  using the paper obtained from the selected tray. Next, the printer processor determines at S 322  whether there are any pages in the print job which have not yet been printed. If there are un-printed pages (S 322 : YES), the printer processor obtains the image for the next page and returns to S 310  to repeat the process for the next page. If there are no un-printed pages (S 322 : NO), the present process could end. 
     Referring to  FIG. 13C , after the printer processor has determined that input sheet sizes are not mixed (i.e., the input sheet size for all pages of a job are either letter-sized or legal-sized), the printer processor determines at S 324  whether image rotation is necessary. The determination at S 324  can be performed according to an orientation combination of first and second image data as described for any one or more of the examples of  FIG. 12 , or it can be performed according to another method. If image rotation is necessary (S 324 : YES), the printer processor proceeds to rotate the image at S 326 , and then determines at S 328  whether the current image is letter-sized. If image rotation is not necessary (S 324 : NO), the printer processor proceeds directly to S 328  to determine whether the current image is letter-sized. If the image is letter-sized (S 328 : YES), the printer processor selects a tray at S 330  that is known contain letter-sized paper oriented in the LEF direction. If the image is not letter-sized (S 328 : NO), the printer processor selects a tray at S 332  that is known contain legal-sized paper. After making the tray selection at S 330  or S 332 , the printer processor causes the image to be printed at S 334  using the paper obtained from the selected tray. Next, the printer determines at S 336  whether there are any pages in the print job which have not yet been printed. If there are un-printed pages (S 336 : YES), the printer processor obtains the image for the next page and returns to S 324  to repeat the process for the next page. If there are no un-printed pages (S 336 : NO), the present process could end. 
     Referring again to  FIG. 13B , by selecting letter-sized paper oriented in the SEF direction at S 316 , it is possible to avoid a mixture of sheet orientations in the output document. As previously discussed, a mixture of sheet orientations in the output document can make subsequent filing of the output document difficult, and may require the user to manually rearrange the pages so that all the long edges are aligned. However, selecting letter-sized paper oriented in the SEF direction may increase print processing time since the linear amount of paper, as measured along conveying path to a photoreceptor drum, will now be based on the long edge of the paper. Therefore, it could be advantageous to provide a query to the user after determining at S 308  ( FIG. 13A ) that input sheet sizes are a mixture of letter and legal size (S 308 : YES) but before proceeding to  FIG. 13B . 
       FIG. 14  shows a variation of  FIG. 13A  which implements the query discussed above.  FIG. 14  is the same as  FIG. 13A  except for the addition of blocks S 338  and S 340 . The printer processor determines at S 308  whether the print job has a mix of legal and letter sheet sizes. If the input sheet sizes are not mixed (S 308 : NO), the process continues to  FIG. 13C . If the input sheet sizes are mixed (S 308 : YES), the printer processor executes at S 338  a query that includes displaying a notification and receiving the user&#39;s instruction. 
       FIG. 15  shows an exemplary query window  342  which includes notification text  344  that asks whether the user will allow letter-sized paper oriented in the SEF direction to be used. Window  342  is displayed on display unit  206 , which may have a touch-sensitive input screen layer  205  covering it. Window  342  includes GUI elements, such as YES and NO buttons  346 . The user provides the printer processor with a user instruction by pushing either the YES or NO button to indicate whether the user allows use of letter-sized paper oriented in the SEF direction. 
     Referring again to  FIG. 14 , the printer processor receives the user instruction at S 338  and then determines at S 340  whether the user has allowed the use of letter-sized paper oriented in the SEF direction. If the user allowed it (S 340 : YES), the process continues to  FIG. 13B . If the user has not allowed it (S 340 : NO), the process continues to  FIG. 13C  instead. 
       FIG. 16  shows an exemplary process for printing that may be performed by host computer  110  or another data processing apparatus in communication with printer  10  or another printer. At S 350 , the host processor receives various print settings. An exemplary host processor is CPU  113  of host computer  110  executing print driver  111 . Print settings can be received via print setting window  122  of  FIG. 7 , for example. At S 352 , the host processor determines whether the user has finished entering all print settings. If no, the host processor continues to receive print settings. If yes, the host processor determines at S 354  whether the print settings include a staple mode selection. If the print settings include a staple mode selection (S 354 : YES), the host processor sends the print job with print settings to the printer at S 356 , after which the present process could end. 
     If instead the print settings do not include a stapling selection (S 354 : NO), the host processor determines at S 358  whether the print settings include an auto tray selection. If the print settings do not include an auto tray selection (S 358 : NO), the host processor sends the print settings to the printer at S 356 , after which the present process may end. 
     If instead the print settings include an auto tray selection (S 358 : YES), the host processor executes at S 360  a query that includes displaying a notification and receiving the user&#39;s instruction. 
       FIG. 17  shows an exemplary query window  362  for S 360  in  FIG. 16 . Window  362  is displayed before the print job is sent to a printer. Window  362  includes notification text  364  that asks whether the user will allow letter-sized paper oriented in the SEF direction to be used. Window  362  is displayed on display unit  116 , which may have touch-sensitive input screen layer  115  covering it. Window  362  includes GUI elements, such as YES and NO buttons  366 . The user provides the host processor with a user instruction by pushing either the YES or NO button in indicate that the user allows the user of letter-sized paper oriented in the SEF direction. 
     Referring again to  FIG. 16 , the printer processor receives the user instruction at S 360  and then sends at S 368  the received user instruction and the print job with print settings to the printer, after which the present process could end. 
     Note that in the process of  FIG. 16 , a user instruction regarding use of letter-sized SEF has been provided to the printer along with the print settings for the print job. Thus, when the printer is handling the print job, there is no need for the printer to display a notification about the use of letter-sized SEF, as was done in S 338  of  FIG. 14 . 
       FIG. 18  shows an alternative to  FIGS. 13A and 14 , which are processes that can be performed by the printer processor.  FIG. 18  is the same as  FIGS. 13A and 14  up to S 308 . If the input sheet sizes are mixed (S 308 : YES), the printer processor determines at S 370  whether the user has allowed letter-sized paper oriented in the SEF direction to be used. The determination at S 370  can be made from a user instruction that was sent with the print settings, such as in S 368  of  FIG. 16 . If the user allowed it (S 370 : YES), the process continues to  FIG. 13B . If the user has not allowed it (S 370 : NO), the process continues to  FIG. 13C  instead. 
     As previously mentioned, the invention may be embodied in or make use of another type of MFP device, copy machine, or printing machine. For example, the printer may have a photoreceptor drum that places the toner image on a transfer belt, and then the transfer belt applies the toner image to the printing media obtained from the trays. The printer may be configured to form color images on the printing media, such as by forming a plurality toner images separately for various process colors, such as cyan, magenta, yellow, and black for CMYK printing, followed by combining the toner images on printing media sheet or a transfer belt. 
     While several particular forms of the invention have been illustrated and described, it will also be apparent that various modifications can be made without departing from the scope of the invention. It is also contemplated that various combinations or subcombinations of the specific features and aspects of the disclosed embodiments can be combined with or substituted for one another in order to form varying modes of the invention. Accordingly, it is not intended that the invention be limited, except as by the appended claims.