Abstract:
Disclosed is an image output system. The image output system comprises input unit for inputting image data, a memory for storing image data input by the input unit, output means for outputting image data stored in the memory, entry means for entering an output condition under which the output means outputs the image data, and an instruction to begin to output the image data, and control unit for controlling an output operation such that the image data is to be output by the output means upon entry of the output condition and the instruction at the entry unit.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image output system and an image output method for visually providing image data that are transmitted, for example, by a computer terminal. 
     2. Related Background Art 
     Recently, a system has been proposed wherein a host computer for editing images, an image processing apparatus for managing images, and a printer, such as a color copying machine, are connected together, and whereby PDL image data are transmitted by the host computer, via a network, to the image processing apparatus whereat they are translated, the resultant image data being transmitted thereafter to the color copying machine to be used to provide high quality images on paper, etc. 
     The functions of current color copying machines have been enhanced, double side copying and sorting/stapling functions, for example, now being provided for copying machines, and consequently, the procedures required of image processing apparatuses to control the printing processes performed by color copying machines have become complicated. In addition, the engine speeds of the copying machines have been increased compared with the speeds of the previous conventional color copying machines. 
     However, the following problems have arisen for the efficiency of the above prior art. Although the cost per sheet for color printing is high, printing failures at color copying machines occur frequently. 
     The translation of PDL image data and the transfer of the resultant image data to a color copying machine, tasks which are performed by an image processing apparatus, may not be performed rapidly enough to keep up with the sequential printing speed available with a color copying machine. In other words, during the printing of a plurality of sheets, the engine of a color copying machine may have to be halted temporarily to wait until data can be received from an image processing apparatus. 
     In this case, the color copying machine can not proceed to the execution of another process, and its work efficiency is very low. 
     In addition, if an operator is dissatisfied with the results of a printing run, image data must be re-transmitted by the host computer. 
     SUMMARY OF THE INVENTION 
     It is, therefore, one object of the present invention to provide an image output system and an image output method to resolve the above described problems. 
     It is another object of the present invention to provide an image output system and an image output method for temporarily holding received image data and for outputting them after an output condition has been designated. 
     It is an additional object of the present invention to provide an image output system and an image output method for developing received image data, and for beginning to output the image data after an output condition has been designated. 
     The above objects and other objects of the present invention will become apparent during the course of the detailed description of the preferred embodiments, given while referring to the following drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram illustrating the arrangement of an image processing apparatus in an image processing system according to a first embodiment of the present invention; 
     FIG. 2 is a block diagram illustrating the entire physical arrangement of the image processing system according to the first embodiment of the present invention; 
     FIG. 3 is a diagram for explaining the structure of a digital color copying machine used for the image processing system according to the first embodiment of the present invention; 
     FIG. 4 is a block diagram illustrating the arrangement of a client computer in the image processing system according to the first embodiment of the present invention; 
     FIG. 5 is a flowchart showing the control process performed by the image processing apparatus in the image processing system according to the first embodiment of the present invention; 
     FIG. 6 is a flowchart showing the control process performed by the digital color copying machine in the image processing system according to the first embodiment of the present invention; 
     FIG. 7 is a flowchart showing the control process performed by an image processing apparatus in an image processing system according to a second embodiment of the present invention; 
     FIG. 8 is a flowchart showing the control process performed by a digital color copying machine in the image processing system according to the second embodiment of present invention; 
     FIG. 9 is a flowchart showing the control process performed by an image processing apparatus in an image processing system according to a third embodiment of the present invention; 
     FIG. 10 is a flowchart showing the processing for the printing, under a different print condition, of image data that are accumulated in the image processing apparatus; and 
     FIG. 11 is a flowchart showing the processing for the selection of an appropriate output mode for printing data. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The preferred embodiments of the present invention will now be described while referring to the accompanying drawings. In the following embodiments, an image processing system comprising a digital color copying machine and an image processing apparatus is shown as an example application of the present; invention. The present invention is not limited to such a system, however, and can be applied to various other apparatuses. 
     [1] First Embodiment 
     The arrangement of an image processing system according to a first embodiment and the arrangements of the individual apparatuses in the system will now be described. FIG. 2 is a diagram for explaining the arrangement of the image processing system according to the first embodiment. The image processing system comprises a digital color copying machine  120 , an image processing apparatus (a PDL translating apparatus)  110 , and a plurality of client computers  101 ,  102  and  103 . 
     The upper portion of the digital color copying machine  120  comprises a digital image reader and a digital image printer for printing a color or a gray scale digital image, and is connected to the image processing apparatus (the PDL translating apparatus)  110 . The image processing apparatus (the PDL translating apparatus)  110  and the client computers  101 ,  102  and  103 , for employment by a plurality of client users, are connected to a network  1 . Only three client computers are shown in FIG. 2, but additional client computers can be connected to the network  1 . 
     The arrangements of the individual apparatuses of the image processing system according to the first embodiment will now be described in detail in the given order: the digital color copying machine  120 , the client computers  101 ,  102  and  103  and the image processing apparatus (the PDL translating apparatus)  110 . 
     FIG. 3 is a diagram for explaining the structure of the digital color copying machine  120 . The digital color copying machine  120  comprises: an images scanner  201  for reading a document image; a signal processor  211  for processing an image signal; a printer  202  for virtually outputting image data on recording sheets; 
     and an operation console  227  at which an operator can input operation instructions. The individual sections are controlled by a CPU in accordance with a program stored in a built-in ROM in the digital color copying machine  120 . In the digital color copying machine  120  is also included a RAM used to store various data. 
     The image scanner  201  includes a mirror faced pressure plate  200 , a document table glass  203 , a lamp  205 , mirrors  206  and  207 , a lens  209 , and a 3-line sensor  210  ( 210 - 1 ,  210 - 2  and  210 - 3 ) for R, G and B. The printer  202  includes a laser driver  212 ; a semiconductor laser  213 ; a polygon mirror  214 ; an f-θ lens  215 ; a mirror  216 ; a photosensitive drum  217 ; a rotary developing unit  218 , having a magenta developer  219 , a cyan developer  220 , a yellow developer  221  and a black developer  222 ; a transfer drum  223 , paper cassettes  224  and  225 ; and a fixing unit  226 . 
     The functions of the above sections will be described in detail. The image scanner  201  reads a document at a resolution of 400 dpi (dots/inch), for example, and performs a digital signal process. The printer  202  prints, on a sheet of paper at a resolution of 400 dpi, a full-color image that corresponds to the document image data read by the image scanner  201 . 
     In the image scanner  201 , a document  204  is placed between the lower face of the mirror faced pressure plate  200  and the upper face of the document table glass (the platen)  203 , and is irradiated by the lamp  205 . The reflected light is guided by the mirrors  206 ,  207  and  208 , passes through the lens  209  and is focused on the 3-line sensor (CCD)  210  to form an image. The image is transmitted to the signal processor  211  as red (R), green (G) and blue (B) color elements of full color data. 
     A drive mechanism (not shown) mechanically drives the lamp  205  and the mirror  206  at velocity V end the mirrors  207  and  208  at velocity (½)V in a direction perpendicular to the electric scanning direction of the line sensor  210 , thereby scanning the face of the document (sub-scanning). 
     The signal processor  211  electrically processes an image signal that is read, and separates the signal into magenta (M), cyan (C), yellow (Y) and black (Bk) elements, which are then transmitted to the printer  202 . Each time the image scanner  201  scans the document, one of the M, C, Y and Bk elements is transmitted to the printer  202 , so that four document scans are performed to complete the reading for the printing of one page. 
     The M, C, Y and Bk image signals originating at the image scanner  201  are transmitted to the laser driver  212  of the printer  202 , and the laser driver  212  modulates the output of the semiconductor laser  213  in consonance with the received image signals. A laser beam emitted by the semiconductor laser  213  passes through the polygon mirror  214 , the f-θ lens  215  and the mirror  216  and impinges on the photosensitive drum  217 . 
     The rotary developing unit  218  includes the magenta developer  219 , the cyan developer  220 , the yellow developer  221  and the black developer  222 . The four developers alternately contact the photosensitive drum  217 , and use their toners to develop an electrostatic latent image formed on the photosensitive drum  217 . Rolled around the transfer drum  223  is a sheet of paper, supplied from either the paper cassette  224  or  225 , to which the image developed on the photosensitive drum  217  is transferred. 
     M, C, Y and Bk color toners are sequentially transferred to the paper in the above described manner, and are fixed to the paper as it is passed through the fixing unit  226 , whereafter it is finally discharged. 
     FIG. 4 is a block diagram illustrating the arrangement of one of the client computers. The client computer, a general-purpose personal computer, comprises a CPU  401 , an image edit controller  402 , a display memory  403 , a display controller  404 , a keyboard/mouse controller  405 , a ROM  406 , a main memory  407 , a hard disk controller  408 , a network controller  409 , a hard disk  410 , a mouse  411 , a display  412 , and a keyboard  413 . 
     The functions of the above individual sections will now be described in detail. The CPU  401  serves as the central control for the client computer, employing a program stored in the ROM  406  or on the hard disk  410 , which the image edit controller  402  performs image layout and editing for the display memory  403 . The display memory  403  is used to store data to be output to the display  412 , and the display controller  404  controls the display  412 . 
     The keyboard/mouse controller  405  controls the mouse  411  and the keyboard  413 . The ROM  406  is used to store a program to be executed by the CPU  401 , and the main memory  407  is used for the storage of various data. The hard disk controller  408  controls the hard disk  410 . 
     The network controller  409  handles communication with the image processing apparatus  110  or other components via the network. The hard disk  410  is used for the temporary storage of image data or for the storage of a variety of other data. The mouse  411  and the keyboard  413  are employed by an operator as input devices for issuing instructions to the client; computer. And the display  412  is used to display the image layout and the edition menu. 
     FIG. 1 is a block diagram illustrating the arrangement of the image processing apparatus  110 . The image processing apparatus  110  comprises a CPU  3011 , a ROM  3012 , an address generation circuit  3022 , a monitor controller  3014 , a host interface  3015 , a serial communication controller  3017 , a DRAM  3013 , an FIFO (First-in First-out) buffer  3018 , an HDD (hard disk) controller  3019 , a built-in HDD  3020 , and a color conversion processor  3021 . 
     The functions of the above sections will now be described in detail. The CPU  3011  controls the entire image processing apparatus  110  via a CPU bus in accordance with a program stored in the ROM  3012 . A fast processing CPU, such as an RISC (Reduced Instruction Set Computer), for the CPU  3011  in order to perform, for example, image development using PDL (Page Description Language) data, which consists of control data and image data, in PostScript (a page description language, developed by Adobe Systems Inc., that is used for printers and is capable of describing the appearance of a page in its entirety, to include fonts, geometric patterns and image graphics). It should be noted that the CPU  3011  handles a variety of other types of image data as well as the PDL data. 
     The ROM  3012  is used to store a program to be executed by the CPU  3011 , while the address generator  3022  generates an address  3023 , which will be described later, and the monitor controller  3014  is used for monitoring queued jobs in order to support a spooling function (a function for activating a low-speed input/output device in parallel with the CPU to increase the processing efficiency of the entire computer). 
     The serial communication controller  3017  provides serial communication with the digital color copying machine  120  (see FIGS. 2 and 3) via an external video interface  3030 . The DRAM  3013  includes a partial region (PDL buffer) and a specified region (frame memory) in which are respectively stored PDL data and a write address, which will be described later. The FIFO buffer  3018  is used to store data  3025  that are transmitted by the digital color copying machine  120  via the external video interface  3030 . 
     The color conversion processor  3021  performs the color conversion of data  3024  that are output by the FIFO  3018 . The HDD controller  3019  controls the built-in HDD  3020 , which is used to store font data. The HDD controller  3019  and the built-in HDD  3020 , and an external video interface  3031  are connected by a SCSI (Small Computer System Interface: a standard interface for connecting peripheral devices to a small computer) bus. 
     The host interface  3015  is a controller for a serial interface, a parallel interface and a LAN (Local Area Network) interface, and receives PDL data from a host computer. Image data from the host computer are transmitted via either the serial interface, the parallel interface or the LAN interface, while a cable can be connected at the same time. 
     The thus received PDL data (including PDIL data temporarily stored in the HDD, etc., of the image processing apparatus  110 ) are stored via the CPU bus in the partial region (a PDL buffer) in the DRAM  3013 . Font data stored in an external HDD are employed and the PDL stored in the partial region of the DRAM  3013  are developed to obtain raster image data (red, green and blue). Then, a write address  3023  for each frame memory is generated by the address generation circuit  3022  and is stored in the specified region (frame memory) in the DRAM  3013 . 
     The digital color copying machine  120  (see FIGS. 2 and 3) in this embodiment is a color electrophotographic copying machine that forms images for a plurality of output color elements, cyan, magenta, yellow and black. In consonance with a sync signal (not shown) from the digital color copying machine  120 , synchronous image data are temporarily stored in the FIFO buffer  3018 . 
     The data  3024  are transmitted from the FIFO buffer  3018  to the color conversion processor  3021  to perform color conversion. That is, the red, green and blue raster image data are converted into raster image data (cyan, magenta, yellow and black) to be printed by the digital color copying machine  120 . Then, the raster image data are transmitted to the external video interface  3030 , and based on the signal, the image forming unit of the digital color copying machine  120  forms images. 
     The control exercised by the image processing apparatus  110  in the image processing system according to the first embodiment will now be described while referring to the flowchart in FIG.  5 . 
     First, when the image processing apparatus  110  is powered on, it is set to the ready state (step S 501 ). The image processing apparatus  110  determines whether PDL data are to be acquired from the host computer, and waits until PDL data are received (step S 502 ). When the PDL data are transmitted by the host computer, other interfaces are set to the busy state to inhibit the receipt of data at the other interfaces (step S 503 ). 
     Following this, the image processing apparatus  110  begins the reception process for the PDL data, and temporarily stores such data in the PDL buffer in the DRAM  3013  (step S 504 ). The received PDL data are developed to obtain raster image data, which thereafter are compressed and stored in the image memory (step S 505 ). Then, a check is performed to determine whether the development of the PDL data to obtain raster image data and the compression and the storage of the raster data in the image memory have been completed (step S 506 ). It should be noted that the data are so compressed that they can be decompressed at high speed. 
     The above described image memory may be either the DRAM  3013  (see FIG. 1) that has a fast access time, or the built-in HDD  3020  (see FIG. 1) that has a low price and a large memory capacity, even though it has a slower access time than does the DRAM  3013 . The selection of the image memory depends on the performance of the entire system, and the memory capacity of the DRAM or the disk that is mounted. 
     In this embodiment, the raster image data obtained by developing the received PDL data, and the image data obtained by decompressing the compressed raster image data, are stored in the DRAM  3013 , while the compressed raster image data are stored in the built-in HDD  3020 . 
     When, at step S 506 , the development of the PDL data to obtain the raster image data, and compression and the storage of the raster image data are terminated, the image processing apparatus  110  transmits to the digital color copying machine  120  image management information to be used to identify the image data stored in the image memory, and the transmission source for the image data (step S 507 ). 
     The image management information can be any information employed for identifying and managing an image that is prepared by the host computer, e.g., a file name for storing the image in a storage device, such as an HDD, or numerals for managing the image. 
     Next, the image processing apparatus  110  determines whether it has received from the digital color copying machine  120  image management information, a designated print condition and a print start command (step S 508 ). Upon the receipt of the entry from a user, the image processing apparatus  110  searches the HDD  3020  for image data to be printed (step S 509 ). Since at steps S 505  and S 506  the image data were compressed and stored in the image memory, the compressed data are decompressed to obtain non-compressed data available for printing (step S 510 ). 
     Following this, in accordance with the print condition designated by the digital color copying machine  120 , the image processing apparatus  110  changes the page order and the direction of the image, and transfers the image data to the digital color copying machine  120  (step S 511 ). 
     The print condition is relative to the performance of the digital color copying machine  120  being used as a printer: a condition whereby, when printed paper sheets stacked on the discharge tray are to be stapled only from the top down, the printing order for pages is changed for the printing of one side or of both sides of the paper sheets, and the image data are output in that order to the digital color copying machine, with the first page of the image data being the topmost page of a stack on the paper discharge tray; or a condition whereby, for example, for double-side image printing, while taking the positions of staples (stapling at one position or at two positions) into account, the image is rotated 180°, depending on whether the direction of the image on the obverse face corresponds to or is opposite to that on the reverse face, and the image data are then output to the digital color copying machine  120 . 
     The image processing apparatus  110  determines whether the transfer of the image data to the digital color copying machine  120  has been completed (step S 512 ). When the transfer of the image data has been terminated, the image processing apparatus  110  is shifted to the ready state (step S 501 ) to wait for the receipt of PDL data. 
     The control performed by the digital color copying machine  120  in the image processing system according to the first embodiment will now be described while referring to the flowchart in FIG.  6 . 
     First, when the digital color copying machine  120  is powered on, it is set to the ready state (step S 601 ). The digital color copying machine  120  then determines whether or not it has received a notice of image management information from the image processing apparatus  110  (step S 602 ). If a notice of image management information has been received, it is assumed that the image data to be printed is stored in the image memory in the image processing apparatus  110 . 
     Next, the digital color copying machine  120  determines whether a user has entered an instruction to display image management information through the operation console  227  (step S 603 ). When the display instruction has been entered, all the image management information transmitted by the image processing apparatus  110  is listed on the display portion of the operation console  227 . In addition, all the print conditions available for the digital color copying machine  120  are also shown (step S 604 ). 
     For example, double-side printing, or stapling (the direction of the staples=whether printed sheets of paper on the discharge tray should be stapled from the top down or from the bottom up, and at how many locations the prints should be stapled), and/or sort printing is shown as the print condition. 
     The digital color copying machine  120  determines whether a user has entered the image management information, designated the print condition and entered a print start command at the operation console  227  (step S 605 ). If the entry has been made by the, user, the image processing apparatus  110  notifies the image processing apparatus  110  of the image management information to be printed and the print conditions, and issues a print start command (step S 606 ). 
     The digital color copying machine  120  determines whether the print start request has been received from the image processing apparatus  110 , and if not, waits until it receives a print start request (step S 607 ). Upon the receipt of the print start request from the image processing apparatus  110 , the digital co:Lor copying machine  120  sets the display on the operation console  227  to a remote print state for the printing of data transmitted by the host computer, and inhibits key input for other processes (step S 608 ). Then, the remote printing is begun (step S 609 ). Subsequently, a check is performed to determine whether or not the remote control printing has been completed (step S 610 ). When the remote control printing has been completed, the digital color copying machine  120  shifts to the ready state (step S 601 ). 
     When, at step S 602 , no notice of the image management information is transmitted by the image processing apparatus  110 , the digital color copying machine  120  ascertains that image data to be printed are not stored in the image memory in the image processing apparatus  110 . A check is then performed to determine whether or not there is a local copy request for directly printing a document image that was read by the image scanner  201  (step S 611 ). If there is no local copy request, the digital color copying machine  120  shifts to the ready state (step S 601 ). 
     If there is a local copy request, the digital color copying machine  120  sets the display on the operation console  227  to a local copy state, and inhibits key input for other processes (step S 612 ). Then, local copying is begun (step S 613 ), during which checks are performed to determine whether or not the local copying has been completed (step S 614 ). When the local copy is found to have been terminated, the digital color copying machine  120  shifts to the ready state (step S 601 ). 
     When at step S 603  no notice of image management information has been received, or when at step S 605  no print start command has been entered at the operation console  227 , the digital color copying machine  120  executes the processing beginning at step S 611 . 
     The input of image data by the digital color copying machine  120  will now be described. The image data, which are read by the image scanner  201  of the digital color copying machine  120 , are transmitted as red, green and blue multi-value dot data to the image processing apparatus  110 . The image data are temporarily stored in the FIFO buffer  3018  (see FIG.  1 ), so that image data can be read synchronously in consonance with a sync signal received from the image processing apparatus  110 . 
     In consonance with the sync signal, the image data are stored in the frame memory  3013  (see FIG. 1) in the image processing apparatus  110 . Then, the address generating circuit  3022  (see FIG. 1) generates an address  3023  to thin out the image data that are stored in the frame memory  3013 , and the resultant data are transmitted via the parallel interface to the host computer. 
     As is described above, according to the first embodiment, the image processing apparatus (PDL translating apparatus)  110  comprises: the CPU  3011 , for developing image data input by a computer to obtain a raster image, for compressing and storing thus raster image on the HDD  3020 , and for searching the HDD  3020  for the image data based on the image management information received from the digital color copying machine  120 ; the HDD  3020 , for storing image data; the color conversion processor  3021 , for performing color conversion of the image data in accordance with an image forming/output instruction from the digital color copying machine  120 ; and the external video interface  3030 , for outputting the image management information and the image data to the digital color copying machine  120 . Therefore, the image processing apparatus  110  can rapidly perform image data processing and transfer of image data to the digital color copying machine  120 , so that the performance of the digital color copying machine  120  can be fully demonstrated, and the number of failures occurring during in the double-sided printing and sorting/stapling printing can be reduced. 
     Further, the printing can be performed at a timing consonant with the engine speed of the digital color copying machine  120 . That is, the down-time spent for temporarily halting the engine during the printing and waiting for image data to be received from the image processing apparatus  110  can be reduced and the performance when printing a plurality of sheets and a plurality of copies can be improved. 
     A reliable system experiencing few failures can be provided for electronically distributed data, and book binding, as desired by a user, can be easily implemented. 
     [2] Second Embodiment 
     The entire arrangement of an image processing system according to a second embodiment, and the arrangements of a digital color copying machine, an image processing apparatus and a client computer in the image processing system are the same as those in the first embodiment (see FIGS. 1 to  4 ). Since their arrangements have been described in detail in the first embodiment, no explanation for them will be given here. 
     In the second embodiment, the available print conditions are programmed in advance, and are stored as print modes in the internal RAM of a digital color copying machine  120 , the print mode being selectable at an operation console  227  on the digital color copying machine  120 . As a result, no labor is required for the designation of a number of print conditions one by one on the operation console  227  of the digital color copying machine  120  and the usability is thereby enhanced. 
     The control performed by an image processing apparatus  110  in the image processing system according to the second embodiment will now be described. while referring to the flowchart in FIG.  7 . 
     First, when an image processing apparatus  110  is powered on, it is set to the ready state (step S 701 ). The image processing apparatus  110  determines whether PDL data are to be acquired from a host computer, and waits until PDL data are received (step S 702 ). When the PDL data are transmitted by the host computer, other interfaces are set to the busy state to inhibit the receipt of data at the other interfaces (step S 703 ). 
     Following this, the image processing apparatus  110  begins the reception process for the PDL data, and temporarily stores such data in the PDL buffer in a DRAM  3013  (step S 704 ). The received PDL data are developed to obtain raster image data, which thereafter are compressed and stored in the image memory (step S 705 ). Then, a check is performed to determine whether the development of the PDL data to obtain raster image data and the compression and the storage of the raster data in the image memory have been completed (step S 706 ). 
     The above described image memory may be either the DRAM  3013  (see FIG. 1) that has a fast access time, or the built-in HDD  3020  (see FIG. 1) that has a low price and a large memory capacity, even though it has a slower access time than does the DRAM  3013 . The selection of the image memory depends on the performance of the entire system, and the memory capacity of the DRAM or the disk that is mounted. 
     In this embodiment, the raster image data obtained by developing the received PDL data, and the image data obtained by decompressing the compressed raster image data, are stored in the DRAM  3013 , while the compressed raster image data are stored in the built-in HDD  3020 . 
     When, at step S 706 , the development of the PDL data to obtain the raster image data, and compression and the storage of the raster image data are terminated, the image processing apparatus  110  transmits to a digital color copying machine  120  image management information to be used to identify the image data stored in the image memory, and the transmission source for the image data (step S 707 ). 
     The image management information can be any information employed for identifying and managing an image that is prepared by the host computer, e.g., a file name for storing the image in a storage device, such as an HDD, or numerals for managing the image. 
     Next, the image processing apparatus  110  determines whether it has received from the digital color copying machine  120  image management information, a designated print condition and a print start: command (step S 708 ). Upon the receipt of the entry from a user, the image processing apparatus  110  searches the HDD  3020  for image data to be printed (step S 709 ). Since at steps S 705  and S 706  the image data were compressed and stored in the image memory, the compressed data are decompressed to obtain non-compressed data available for printing (step S 710 ). 
     Following this, in accordance with the print mode designated by the digital color copying machine  120 , the image processing apparatus  110  changes the page order and the direction of the image, and transfers the image data to the digital color copying machine  120  (step S 711 ). 
     The print mode is a combination of several print conditions, such as a double-side and sorting mode, a double-side and stapling (two staplings) mode, or a one-side and sorting/stapling (one stapling) mode. A user need only select a desired print mode at the operation console. Therefore, since the user does not have to choose one by one from a number of print conditions, but simply selects a mode, the usability is improved. 
     The image processing apparatus  110  determines whether the transfer of the image data to thee digital color copying machine  120  has been completed (step S 712 ). When the transfer of the image data has been terminated, the image processing apparatus  110  is shifted to the ready state (step S 701 ) to wait for the receipt of PDL data. 
     The control performed by the digital color copying machine  120  in the image processing system according to the second embodiment will now be described while referring to the flowchart in FIG.  8 . 
     First, when the digital color copying machine  120  is powered on, it is set to the ready state (step S 801 ). The digital color copying machine  120  then determines whether or not it has received a notice of image management information from the image processing apparatus  110  (step S 802 ). If a notice of image management information has been received, it is assumed that the image data to be printed is stored in the image memory in the image processing apparatus  110 . 
     Next, the digital color copying machine  120  determines whether a user has entered an instruction to display image management information through the operation console  227  (step S 803 ). When the display instruction has been entered, all the image management information transmitted by the image processing apparatus  110  is listed on the display portion of the operation console  227 . In addition, all the print modes available for the digital color copying machine  120  are also shown (step S 804 ). 
     For example, the double-side and sorting mode, the double-side and stapling (two staplings) mode, or the one-side and sorting/stapling mode, is displayed. Further, a mode that the user designates frequently can be programmed in advance, and a double-side mode involving bookbinding for the double-side printing of pages 1, 2, N- 1  and N of a document having N pages can be programmed. 
     The digital color copying machine  120  determines whether a user has entered the image management information, designated the print condition and entered a print start command at the operation console  227  (step S 805 ). If the entry has been made by the user, the image processing apparatus  110  notifies the image processing apparatus  110  of the image management information to be printed and the print conditions, and issues a print start command (step S 806 ). 
     The digital color copying machine  120  determines whether the print start request has been received from the image processing apparatus  110 , and if not, waits until it receives a print start request (step S 807 ). Upon the receipt of the print start request from the image processing apparatus  110 , the digital color copying machine  120  sets the display on the operation console  227  to a remote print state for the printing of data transmitted by the host computer, and inhibits key input for other processes (step S 808 ). Then, the remote printing is begun (step S 809 ). Subsequently, a check is performed to determine whether or not the remote control printing has been completed (step S 810 ). When the remote control printing has been completed, the digital color copying machine  120  shifts to the ready state (step S 801 ). 
     When, at step S 802 , no notice of the image management information is transmitted by the image processing apparatus  110 , the digital color copying machine  120  ascertains that image data to be printed are not stored in the image memory in the image processing apparatus  110 . A check is then performed to determine whether or not there is a local copy request for directly printing a document image that was read by the image scanner  201  (step S 811 ). If there is no local copy request, the digital color copying machine  120  shifts to the ready state (step S 801 ). 
     If there is a local copy request, the digital color copying machine  120  sets the display on the operation console  227  to a local copy state, and inhibits key input for other processes (step S 812 ). Then, local copying is begun (step S 813 ), during which checks are performed to determine whether or not the local copying has been completed (step S 814 ). When the local copy is found to have been terminated, the digital color copying machine  120  shifts to the ready state (step S 801 ). 
     When at step S 803  no notice of image management information has been received, or when at step S 805  no print start command has been entered at the operation console  227 , the digital color copying machine  120  executes the processing beginning at step S 811 . 
     As is described above, according to the second embodiment, the image processing apparatus (PDL translating apparatus)  110  comprises: the CPU  3011 , for developing image data input by a computer to obtain a raster image, and then compressing and storing the raster image on the HDD  3020 , and for searching the HDD  3020  for the image data based on the image management information received from the digital color copying machine  120 ; the HDD  3020 , for storing image data; the color conversion processor  3021 , for performing color conversion of the image data in accordance with an image forming/output instruction from the digital color copying machine  120 ; and the external video interface  3030 , for outputting the image management information and the image data to the digital color copying machine  120 . Therefore, the image processing apparatus  110  can rapidly perform image data processing and transfer of image data to the digital color copying machine  120 , so that the performance of the digital color copying machine  120  can be fully demonstrated, and the number of failures occurring during in the double-sided printing and sorting/stapling printing can be reduced. 
     Further, the printing can be preformed at a timing consonant with the engine speed of the digital color copying machine  120 . That is, the down-time spent for temporarily halting the engine during the printing and waiting for image data to be received from the image processing apparatus  110  can be reduced, and the performance when printing a plurality of sheets and a plurality of copies can be improved. 
     A reliable system experiencing few failures can be provided for electronically distributed data, and book binding, as desired by a user, can be easily implemented. 
     Since the available print conditions can be programmed in advance as a print mode, which (can be selected at the operation console  227  of the digital color copying machine  120 , the labor involved in the one-by-one designation of a number of print conditions at the operation console  227  is eliminated, and the usability is improved. 
     [3] Third Embodiment 
     The entire arrangement of an image processing system according to a third embodiment, and the arrangements of a digital color copying machine, an image processing apparatus and a client computer in the image processing system are the same as those in the first embodiment (see FIGS. 1 to  4 ). Since their arrangements have been described in detail in the first embodiment, no explanation for them will be given here. 
     As the feature of the third embodiment, an operation console is provided for an image processing apparatus  110 , and print conditions or a print mode can be designated using the operation console. 
     The control performed by the image processing apparatus  110  in the image processing system according to the third embodiment will now be described while referring to the flowchart in FIG.  9 . 
     First, when the image processing apparatus  110  is powered on, it acquires available print conditions and/or modes from a digital color copying machine  120  (step S 901 ), and is set to the ready state (step S 902 ). The image processing apparatus  110  determines whether PDL data are to be acquired from a host computer, and waits until PDL data are received (step S 903 ). When the PDL data are transmitted by the host computer, other interfaces are set to the busy state to inhibit the receipt of data at the other interfaces (step S 904 ). 
     Following this, the image processing apparatus  110  begins the reception process for the PDL data, and temporarily stores such data in the PDL buffer in a DRAM  3013  (step S 905 ). The received PDL data are developed to obtain raster image data, which thereafter are compressed and stored in the image memory (step S 906 ). Then, a check is performed to determine whether the development of the PDL data to obtain raster image data and the compression and the storage of the raster data in the image memory have been completed (step S 907 ). 
     The above described image memory may be either the DRAM  3013  (see FIG. 1) that has a fast access time, or the built-in HDD  3020  (see FIG. 1) that has a low price and a large memory capacity, even though it has a slower access time than does the DRAM  3013 . The selection of the image memory depends on the performance of the entire system, and the memory capacity of the DRAM or the disk that is mounted. 
     In this embodiment, the raster image data obtained by developing the received PDL data, and the image data obtained by decompressing the compressed raster image data, are stored in the DRAM  3013 , while the compressed raster image data are stored in the built-in HDD  3020 . 
     When, at step S 907 , the development of the PDL data to obtain the raster image data, and the compression and the storage of the raster image data are terminated, the image processing apparatus  110  determines whether or not a user has issued an instruction using the operation console  227  to display image management information corresponding to the image data stored in the image memory (step S 908 ). If such an instruction has been issued, all the image management information and the print conditions and/or modes available for the digital color copying machine  120  are displayed (step S 909 ). 
     Next, the image processing apparatus  110  waits for the entry of image management information, the selection of print conditions and/or modes, and the entry of a print start command at the operation console  227  (step S 910 ). If such entries are made, the image processing apparatus  110  searches for image data to be printed based on the image management information (step S 911 ). Since at steps S 906  and S 907  the image data were compressed and stored in the image memory, the compressed data are decompressed to obtain non-compressed data available for printing (step S 912 ). 
     Following this, in accordance with the print mode designated by the digital color copying machine  120 , the image processing apparatus  110  changes the page order and the direction of the image, and transfers the image data to the digital color copying machine  120  (step S 913 ). The image processing apparatus  110  determines whether the transfer of the image data to the digital color copying machine  120  has been completed (step S 914 ). When the transfer of the image data has been terminated, the image processing apparatus  110  is shifted to the ready state (step S 902 ) to wait for the receipt of PDL data. 
     As is described above, according to the third embodiment, the image processing apparatus (PDL translating apparatus)  110  comprises: the CPU  3011 , for developing image data input by a computer to obtain a raster image, for compressing and storing the raster image on the HDD  3020 , and for searching the HDD  3020  for the image data based on the image management information received from the digital color copying machine  120 ; the HDD  3020 , for storing image data; the color conversion processor  3021 , for performing color conversion of the image data in accordance with an image forming/output instruction from the digital color copying machine  120 ; and the external video interface  3030 , for outputting the image management information and the image data to the digital color copying machine  120 . Therefore, the image processing apparatus  110  can rapidly perform image data processing and transfer of image data to the digital color copying machine  120 , so that the performance of the digital color copying machine  120  can be fully demonstrated, and the number of failures occurring during in the double-sided printing and sorting/stapling printing can be reduced. 
     Further, the printing can be preformed at a timing consonant with the engine speed of the digital color copying machine  120 . That is, the down-time spent for temporarily halting the engine during the printing and waiting for image data to be received from the image processing apparatus  110  can be reduced, and the performance when printing a plurality of sheets and a plurality of copies can be improved. 
     A reliable system experiencing few failures can be provided for electronically distributed data, and book binding, as desired by a user, can be easily implemented. 
     In addition, since the operation console  227  is provided for the image processing apparatus  110  and print conditions or a print mode can be designated using the operation console  227 , usability is improved. 
     In addition to the processing performed in the first to the third embodiments, in which the data received from the host computer  9  are temporarily held by the image processing apparatus  110  and are printed in consonance with a print condition and a print start instruction entered by the operator, the following processing can be performed to enhance usability. 
     For example, when the style of the printed result is not the one desired, re-printing can be performed under a different print condition. 
     This processing will now be explained. 
     FIG. 10 is a flowchart showing the processing performed by the digital color copying machine  120 . 
     First, at step S 1001 , as well as at step, S 610  in FIG.  6  and at step S 810  in FIG. 8, a check is performed to determine whether remote printing has been terminated. 
     Then, at step S 1002  a check is performed to determine whether an instruction has been entered at the operation console  227  that specifies the deletion, in consonance with image management information, of the accumulated image data that are stored in the image processing apparatus  110 . When deletion is not instructed, program control advances to step S 1003 , whereat a check is performed to determine whether an instruction has been entered at the operation console  227  to change the print condition. If the alteration of the print condition has been instructed, at step S 1004  a new print condition is designated. When, at step S 1005 , a printing start is instructed, Fat step S 1006 , in accordance with the designated print condition, pertinent image data are received from the image processing apparatus  100  and are printed. When, at step S 1007 , it is ascertained that the printing has been completed, the above process is repeated until the deletion of image data is instructed. 
     Upon the receipt of an instruction entered at the operation console  227  to delete image data, at step S 1008  the image processing apparatus  110  deletes the image data. 
     Through the processing shown in FIG. 10, the image data accumulated in the image processing apparatus  110  can be repeatedly printed under various print conditions. 
     In the above explanation, the image data from the host computer are stored in the image processing apparatus  110 , and are then printed upon the receipt of a print start instruction from an operator. However, as in normal printing, image data transmitted by the host computer can be printed by changing the print condition to that designated by the host computer, as needed and without operator entry being required. 
     FIG. 11 is a flowchart showing the processing performed by the image processing apparatus  110  in this case. 
     A mode in which image data are temporarily stored and are then printed in response to a print instruction issued by an operator is called a waiting mode, and a mode in which image data are printed without operator entry being required is called an automatic output mode. 
     First, at step S 1101  a check is performed to determine whether or not the waiting mode has been designated. The mode may be designated by the host computer, or it may be set in advance by the image processing apparatus  110  or the digital color copying machine  120 . 
     When the waiting mode is not designated, at step S 1102  the automatic output mode is set. If, at step S 1103 , it is ascertained that the digital color copying machine  120  is ready for printing, program control advances to step S 1104 , whereat image data to be printed are transferred to the digital color copying machine  120  and printed. When, at step S 1105 , it is ascertained that the transfer of image data has been completed, the image processing apparatus  110  is shifted to the ready state. It should be noted that the image data are stored on the HDD  3020  until a deletion instruction is received. 
     When the waiting mode has been designated, at step S 1106  the printing is begun as previously described. 
     Through the processing in FIG. 11, therefore, image data can be output using a desired method. 
     In the above description, the image data are transmitted by the host computer, but image data may also be transmitted, for example, by a scanner that reads a document image. 
     The flowcharts in FIGS. 5 to  11  show the operations performed by the CPUs of the individual apparatuses based on program data loaded into the memories of these apparatuses. Appropriate hardware circuits can take the place of the program data for the performance of these operations. 
     The present invention can be applied to a system constituted by a plurality of devices or to an apparatus that includes only one device. The present invention can also be implemented by providing for the system, or an apparatus, a storage medium on which is stored software program code that implements the functions of the above embodiments, so that the computer of the system, or of the apparatus, can read and execute the program code that is stored on the storage medium. 
     In this case, the program code read from the recording medium implements the functions of the embodiments, and the storage medium embodies; the present invention. 
     The storage medium for supplying program code is, for example, a floppy disk, a hard disk, an optical disk, a magneto optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card or a ROM. 
     Since the program code is read and executed by the computer, included is not only a case where the functions of the above embodiments are accomplished, but also a case where an OS running on the computer performs one part or all of the actual processing, in accordance with the instructions contained in the program code, so as to implement the functions of the embodiments. 
     The present invention has been explained by using the preferred embodiments; however, the present invention is not limited to these embodiments and can be variously modified within the scope of the claims.