JP2008028918A - Image drawing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of reproducing simulation at a small cost at execution. <P>SOLUTION: Processes whose color value is not 0 before color conversion by CMYK simulation are overprinted by colors after the CMYK simulation and processes whose color value is 0 before the color conversion by the CMYK simulation are subjected to OR-printing by the colors after the CMYK simulation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a drawing apparatus that interprets a page description language and generates a color bitmap image.

  Receives data described in Page Description Language (PDL) via a communication medium such as a network, interprets it with a dedicated interpreter, performs RIP processing to form an image, and uses a print engine such as electrophotography Page printers that print and output are widely known. The page description language data is generated from the original electronic document by cooperation between the application, the operating system, and the driver.

  In RIP processing of page description language data, intermediate data is often output by PDL interpretation by software processing, and a bitmap image is generated from the intermediate data by rendering by hardware processing or software processing. In rendering, it is normal to convert drawing objects to raster images and overwrite them in the specified order. However, in many page description languages, drawing objects (foreground) for overprinting, raster operation processing, etc. are already It has a function of drawing based on the result of calculation with the drawn background. 9 and 10 show examples of drawing during normal drawing and overprinting. FIG. 9 shows a drawing example when the rectangle of 4101 drawing object B is normally drawn after the rectangle of 4102 drawing object B is normally drawn. The overlapping portion of the two rectangles is overwritten by the object drawn later. On the other hand, FIG. 10 shows a drawing example when the rectangle of 4202 drawing object B is normally drawn and then the rectangle of 4201 drawing object A is overprinted. The overlapping part of the two rectangles is the drawing object B on the back and the drawing object B on the front. Both colors with drawing object A are combined. FIG. 11 illustrates a color composition method by overprinting based on the drawing example of FIG. The drawing object A in the front has a color value (C, M, Y, K) = (165, 0, 0, 0), and the color value is 0 except for the cyan (C) version. The drawing object B on the back has color values (C, M, Y, K) = (235, 64, 0, 0). In overprinting, the color value 0 (color component) retains the back color, and the color value non-zero (color component) is overwritten by the front color value, so the color value of the drawing object A on the front Only the cyan version is overwritten, and the color value of the part where the two drawing objects overlap is (C, M, Y, K) = (165,64,0,0).

For example, Patent Literature 1 can be cited as a conventional example.
JP 2004-153331 A

  Some recent color printers have a CMYK simulation function for simulating and outputting the color of a specific commercial printing ink for the color specified by CMYK. The CMYK simulation performs non-linear color conversion from CMYK to CMYK. In the case of a normal overwritten drawing object, color conversion can be performed at either time before or after rasterization. However, for an overprinted area, it is necessary to perform color conversion on the color after being synthesized by overprint drawing. As shown in FIG. 12, when the color conversion by the CMYK simulation is performed first, a color component having a color value of 0 in the original color often appears, and overprinting is not executed correctly. Even if a color component having a color value of 0 in the original color has a color value of 0 after the conversion, it is a non-linear color conversion, so there is no guarantee that the color will be the same as the color converted after overprinting. Generally, color conversion is performed on a bitmap image generated by rendering, but the area drawn in a color space other than CMYK that is not the target of CMYK simulation and the CMYK color that is the target of CMYK simulation It is necessary to distinguish the area drawn in space. It is clear that the process of performing color conversion while determining the color space for each pixel is a very expensive process.

  Therefore, in the present invention, a color component whose color value before color conversion by CMYK simulation is non-zero is overwritten with the color value of the color component after color conversion by CMYK simulation, and the color value before color conversion by CMYK simulation is 0. As for the color component, the color value of the color component after the color conversion by the CMYK simulation is ORed with the back color to simulate the overprint and the CMYK simulation.

  According to the present invention, it is possible to easily perform color management processing such as overprinting and CMYK simulation simultaneously without enormous execution cost of executing color conversion processing after composition by overprinting.

  Hereinafter, an embodiment according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating the overall configuration of an image forming apparatus system according to an embodiment of the present invention. The image forming apparatus 200 includes a scanner unit 2070 that is an image input device, a printer unit 2095 that is an image output device, a controller unit 2000, and an operation unit 2012 that is a user interface. The scanner unit 2070, the printer unit 2095, and the operation unit 2012 are each connected to the Controller Unit 2000, and the Controller Unit 2000 is connected to a network transmission means such as LAN 2011. In addition, other image forming apparatuses 220 and 230 having the same device configuration as the image forming apparatus 200 are connected to the LAN 2011. The image forming apparatuses 220 and 230 have scanner units 2270 and 2370, printer units 2295 and 2395, and operation units 2212 and 2312, which are connected to the Controller Units 2200 and 2300, respectively.

  FIG. 2 is a software block diagram of the image forming apparatus showing the embodiment of the present invention. Reference numeral 1501 denotes a UI, that is, a user interface, and is a module that mediates with the device when the operator performs various operations and settings of the image forming apparatus. This module transfers input information to various modules, which will be described later, and requests processing or sets data in accordance with the operation of the operator. Reference numeral 1502 denotes an address-book, that is, a database module that manages data transmission destinations, communication destinations, and the like. The contents of the Address-Book are used to add, delete, and acquire data by operations from the UI 1501, and to provide data sending / communication destination information to each module described later by operations by the operator. . Reference numeral 1504 denotes a universal-send, that is, a module that manages data distribution, and distributes data instructed to the operator by the UI 1501 to a communication (output) destination similarly designated. When the operator uses the scanner function of this device to instruct distribution data generation, the device is operated via the Control-API 1519 described later to generate data. A module 1505 is executed when a printer is designated as an output destination in the Universal-Send 1504. A module 1506 is executed when an e-mail address is specified as a communication destination in the Universal-Send 1504. A module 1507 is executed when a database is specified as an output destination in the Universal-Send 1504. A module 1508 is executed when an image forming apparatus similar to this apparatus is designated as an output destination in the Universal-Send 1504. A PDL module 1509 realizes a function of printing a PDL (Page Description Language) document transmitted from the outside of the image forming apparatus by using the print function of the image forming apparatus. It also provides a function to retrieve and print electronic documents stored on an external Web server using the 1512 HTTP module. A Copy module 1510 uses the printer function and the scanner function of the image forming apparatus, and executes a Copy operation based on a UI instruction. 1511 is a box module (Box) that stores scanned images or PDL print images on the HDD, prints the stored images using the printer function, transmits them using the Universal-Send function, deletes documents stored on the HDD, and groups (individual boxes) Management functions such as storage in a folder), movement between boxes, and copying between boxes. A module 1512 is used when the image forming apparatus communicates by HTTP, and provides communication to the PDL 1509 module described above by a TCP / IP 1516 module described later. Reference numeral 1513 denotes an lpr module that provides communication to the printer module 1505 in the above-mentioned Universal-Send 1504 by a TCP / IP 1517 module described later. Reference numeral 1514 denotes an SMTP module which provides communication to the E-mail module 1506 in the above-mentioned Universal-Send 1504 by a TCP / IP 1517 module described later. Reference numeral 1515 denotes an SLM, that is, a Salutation-Manager module, which provides communication to the database module 1517 and the DP module 1518 in the aforementioned Universal-Send 1504 by a TCP / IP 1517 module described later. An LPD module 1516 provides communication to the PDL 1509 module described above by a TCP / IP 1517 module described later. Reference numeral 1517 denotes a TCP / IP communication module, which provides network communication to the various modules described above using a network driver described later. A network driver 1518 controls a portion physically connected to the network. 1519 is a Control-API that provides an interface with lower-level modules such as Job-Manager 1520 (described later) for higher-level modules such as Universal-Send 1504, PDL 1509, Copy 1510, and Box 1511. In addition, the dependency between the lower modules and the lower modules is reduced, and each diversion is enhanced. Reference numeral 1520 denotes a Job-Manager that interprets processing instructed from the various modules described above via the Control-API 1519 and gives instructions to each module described later. Further, this module centrally manages hardware processing executed in the image forming apparatus. Reference numeral 1521 denotes a CODEC-Manager that manages and controls various types of data compression / decompression in the process instructed by the Job-Manager 1520. Reference numeral 1522 denotes an FBE-Encoder, which compresses data read by a scan process executed by the Job-Manager 1520 and the Scan-Manager 1525 in the FBE format. 1523 is a JPEG-CODEC, which performs JPEG compression of read data and JPEG expansion processing of print data in scan processing executed by Job-Manager 1520 and Scan-Manager 1525 and print processing executed by Print-Manager 1526. Is what you do. 1524 is an MMR-CODEC. In the scan processing executed by the Job-Manager 1520 and the Scan-Manager 1525 and the print processing executed by the Print-Manager 1526, the MMR compression of the read data and the MMR decompression of the print data are performed. The processing is performed. Reference numeral 1525 denotes a Scan-Manager, which manages and controls scan processing instructed by the Job-Manager 1520. Reference numeral 1528 denotes a scanner I / F, which provides an I / F between the Scan-Manager 1524 and a scanner unit to which the image forming apparatus is internally connected. Reference numeral 1526 denotes a Print-Manager that manages and controls print processing instructed by the Job-Manager 1519. An engine-I / F driver 1529 provides an interface between the print manager 1526 and the printing unit. A PDL interpreter 1527 interprets the PDL or electronic document format according to an instruction from the Job-Manager 1520, and generates a display list that is a common expression format regardless of the type of the PDL or electronic document format. Reference numeral 1530 denotes a Render, which expands the display list generated by the PDL Interpreter 1527 in a raster image memory using an image processor in accordance with an instruction from the Print-Manager 1520.

  FIG. 3 is a block diagram illustrating the configuration of the image forming apparatus. The Controller Unit 2000 connects to the scanner 2070, which is an image input device, and the printer 2095, which is an image output device. On the other hand, the controller unit 2000 is connected to a LAN 2011 or a public line (WAN) 2051 to input and output image information and device information. It is a controller. The CPU 2001 is a controller that controls the entire system. A RAM 2002 is a system work memory for operating the CPU 2002, and is also an image memory for temporarily storing image data. ROM 2003 is a boot ROM, which stores a system boot program. HDD 2004 is a hard disk drive that stores system software and image data. An operation unit I / F 2006 is an operation unit (UI) 2012 and an interface unit, and outputs image data to be displayed on the operation unit 2012 to the operation unit 2012. Also, it plays a role of transmitting information input from the operation unit 2012 by the system user to the CPU 2001. Network2010 connects to LAN2011 and inputs / outputs information. A Modem 2050 is connected to the public line 2051 and inputs / outputs information. The above devices are arranged on the system bus 2007. Image Bus I / F2005 is a bus bridge that connects a system bus 2007 and an image bus 2008 that transfers image data at high speed, and converts the data structure. The image bus 2008 is configured by a PCI bus or IEEE1394. The following devices are arranged on the image bus 2008. An image processor (RIP) 2060 expands the display list into a raster image. A device I / F unit 2020 connects an image input / output device such as a scanner 2070 and a printer 2095 to the controller 2000, and performs synchronous / asynchronous conversion of image data. A scanner image processing unit 2080 corrects, processes, and edits input image data. A printer image processing unit 2090 performs printer correction, resolution conversion, halftoning, and the like on print output image data. The image rotation unit 2030 rotates image data. The image compression unit 2040 performs compression / expansion processing of JPEG for multi-valued image data and JBIG, MMR, and MH for binary image data.

  The appearance of the image forming apparatus is shown in FIG. A scanner unit 2070 serving as an image input device illuminates an image on paper as an original and scans a CCD line sensor (not shown), thereby converting the image into raster signal data 2071 into an electrical signal. The manuscript paper is set on the tray 2073 of the manuscript feeder 2072, and when the apparatus user gives an instruction to start reading from the operation unit 2012, the controller CPU2001 gives an instruction to the scanner 2070 (2071), and the feeder 2072 copies the manuscript paper one by one. Feeds and reads the original image. The printer unit 2095, which is an image output device, is a part that converts raster image data 2096 into an image on paper. The method is an electrophotographic method using a photosensitive drum or a photosensitive belt, and ink is ejected from a micro nozzle array. In addition, there is an ink jet method for printing an image directly on a sheet, but any method may be used. The start of the printing operation is started by an instruction 2096 from the controller CPU2001. The printer unit 2095 has a plurality of paper feed stages so that different paper sizes or different paper orientations can be selected, and has paper cassettes 2101, 2102, 2103 corresponding thereto. A paper discharge tray 2111 receives paper that has been printed.

  The configuration of the operation unit 2012 is shown in FIG. The LCD display unit 2013 has a touch panel sheet 2019 pasted on the LCD, displays a system operation screen and soft keys, and transmits the position information to the controller CPU 2001 when the displayed keys are pressed. A start key 2014 is used when starting a document image reading operation. In the center of the start key 2014, there is a green and red two-color LED 2018, which indicates whether or not the start key 2014 can be used. The stop key 2015 works to stop the running operation. The ID key 2016 is used when inputting the user ID of the user. A reset key 2017 is used when initializing settings from the operation unit.

  FIG. 6 is a block diagram illustrating the configuration of the operation unit of the image forming apparatus. In the image forming apparatus, reference numeral 2001 denotes a control CPU, which comprehensively controls access to various devices connected to the system bus 2007 based on a control program stored in the 2003 program ROM and the 2004 HDD. Input information is read from the scanner 2070 connected via the interface 2071, and an image signal as output information is output to the printing unit 2095 connected via the printing unit interface 2096. 2002 is a RAM that functions as the main memory, work area, etc. of the CPU of 2001. User input is received from the touch panel in 2019 and hard keys in 2014 to 2017, and the operation content is acquired via the operation input unit I / F 20061. Based on the acquired operation content and the above-mentioned control program, display screen data is generated in the CPU 2001, and the display screen is output to the screen output device 2013 such as LCD or CRT via the output device controller 20062 that controls the screen output device. To do.

  Next, the flow of RIP processing for interpreting the page description language and forming an image will be described with reference to FIG. The page description language interpreter 3001 is one of the PDL Interpreters 1527 in FIG. 2, and interprets data described in the page description language to generate a display list 3015 that is intermediate language data. The language processing unit 3004 interprets data described in the page description language and issues a drawing request to each drawing processing unit of the character processing unit 3005, the graphics processing unit 3006, and the image processing unit 3007 in accordance with the drawing operator. . Further, the language processing unit recognizes the overprint start command and the overprint end command, and informs the character processing unit 3005 and the graphic processing unit 3006 of whether or not the drawing object requires overprinting. The character processing unit 3005 generates a character bitmap from a specified font, the graphics processing unit 3006 controls vector graphics drawing, and the image processing unit 3007 uses image data as a common internal data format. The process etc. which convert to are performed. The CMS engine 3008 is a module that performs color management, and generates an output color (CMYK) specific to the printer engine after converting the input color to an absolute color space. The page description language defines various color spaces such as Device color space, CIEBased color space, and special color space. Input colors specified in the Device color space are prepared in advance, such as RGB source profiles and CMYK simulation profiles. Color conversion is performed using the specified ICC profile group. For input colors specified in the CIEBased color space, color conversion is performed according to the conversion table, conversion function, and conversion matrix specified in the color space. Conversion from the absolute color space to the color space specific to the printer engine is performed using an output profile or a Color Rendering Dictionary defined in a page description language. A color determination unit 3009 checks the CMYK color, which is an output value of the CMS engine, and determines whether the currently processed page is a color page or a monochrome page. The display list generator 3010 generates a display list 3015 that is intermediate language data. In the display list generator 3010, whether or not overprint processing is required for each drawing object and the color values before and after color conversion by the CMS engine are transmitted from the upper module, and appropriate for overwriting or overprinting for each drawing object. The raster operation mode is set. For drawing objects that require overprint processing, set the raster operation mode to perform drawing that masks color components that have non-zero color values before color conversion, and then use the color values after color conversion for the back color. The raster operation mode is set to perform OR drawing. The display list includes an attribute flag for each object, and identifies whether the object is a graphic, an image, or a character. The attributes notified from the character processing unit 3005, the graphics processing unit 3006, and the image processing unit 3007 are used as they are. The attribute flag is used for subsequent image processing after rendering. The display list includes raster operation information for each object, and it is identified whether or not the object requires raster operation processing. The renderer 3002 interprets the display list and generates CMYK bitmaps 3016 each having a bit depth of 8 × 4. Most of the processing is performed using the RIP 2060 in FIG. The renderer rasterizes the drawing objects included in the display list and sequentially develops them on the page memory constituting the CMYK bitmap having a bit depth of 8 × 4. The renderer has the raster operation modes listed in FIG. 14, and in accordance with the raster operation mode specified for each drawing object, the drawing object that has already been drawn (that is, the background, dest in FIG. 14) and the drawing object to be drawn next. Raster operation processing is executed with (ie, foreground, src in FIG. 14), and the rendering result (result in FIG. 14) is developed on the page memory. In addition, the renderer generates an object attribute map 3017 indicating the attribute for each device pixel unit as the fifth version based on the attribute flag included in the display list 3015. Here, the object attribute map has attribute information of bit depth 2 (graphics 01, image 10, character 11) for each pixel. The image processor 3003 is controlled by the Print Manager 1526 shown in FIG. 2, and performs image processing such as density / color balance adjustment 3011, output gamma correction 3012, and halftoning 3013 on the CMYK bitmap 3016 generated by the render 3002. It is. Halftoning 3013 refers to object attribute map 3017 and applies different halftoning for each object attribute. For graphics attributed image areas, a resolution-prioritized high-frequency screen is used, and image attributed image areas. Is applied to a low resolution screen giving priority to gradation, and error diffusion is applied to an image area having character attributes. If the color determination unit 3009 determines that the page is a monochrome page, only the K version bitmap of the CMYK bitmap 3016 created by the render 3002 is sent to the image processor 3003 and used in the final output. A map 3019 is generated. If the color determination unit 3009 determines that the page is a color page, the CMYK bitmap 3016 generated by the render 3002 is sent to the image processor 3002 as it is, and a CMYK bitmap 3018 used for final output is generated. The In this way, the CMYK bitmap 3014 or the K bitmap 3015 generated by the image processor 3003 is transferred to the printer engine via the Engine I / F 1529 in FIG. 2 and printed out on a desired medium.

  FIG. 8 is a flowchart showing an overprint drawing procedure by the display list generator. The flowchart in FIG. 8 is executed for each drawing object, and starts from S3101. In S3102, it is determined whether or not the drawing object is overprinted. If Yes, the process proceeds to S3110, and if No, the process proceeds to S3103 to determine whether the color space is other than the DeviceCMYK color space. If Yes, the process proceeds to S3110, and if No, the process proceeds to S3104. In S3104, a mask pattern for erasing a color component whose color value before color conversion is non-zero is generated and set as a color value of the drawing object. For example, if the color value before color conversion is (C, M, Y, K) = (165, 0, 0, 0), the only color component with a non-zero color value is cyan, so only the cyan version Is generated and 0x00ffffff is generated as a mask pattern that leaves other color components. Next, in S3105, the raster operation mode is set to MASK. In step S3106, the drawing object is drawn, that is, written to the display list. At this time, the color value set in S3104 and the raster operation and mode set in S3105 are output to the display list as the drawing attributes of the drawing object. Hereinafter, unless otherwise specified, it is assumed that the color value and raster operation mode set before drawing are set as drawing attributes. Next, the process proceeds to S3107, the color value after color conversion is set as the color value of the drawing object, and the process proceeds to S3108. In S3108, the raster operation mode is set to MERGE, and the process proceeds to S3109. In step S3109, the drawing object is written to the display list again. On the other hand, if Yes in S3102 or S3103, that is, normal drawing instead of overprinting, the color value after color conversion is set as the color value of the drawing object in S3110, and the raster operation mode is set to COPY in S3111 In step S3112, writing to the display list is performed.

  FIG. 13 illustrates the overprint process according to the present invention, taking the overlapping area in FIG. 2 as an example. The color component having a non-zero color value before color conversion by CMYK simulation is only cyan, and the color value after color conversion (C = 169) is overwritten as it is. The magenta, yellow, and black versions have a color value before color conversion by CMYK simulation of 0, so the color value on the back side (M = 67, M = 4, Y = 6, K = 1) , Y = 5, K = 29), the color value is ORed (M = 67, Y = 6, K = 2).

  The present invention may be applied to a system including a plurality of devices including a printer (for example, a host computer, an interface device, a scanner, a printer, etc.), or may be applied to a single printer device.

  Another object of the present invention is to supply a storage medium (or recording medium) in which a program code of software that realizes the functions of the above-described embodiments is recorded to a system or apparatus, and the computer (or CPU or CPU) of the system or apparatus. The program code itself stored in the storage medium realizes the function of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.

  Further, after the program code read from the storage medium is written in a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the CPU or the like provided in the card or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

Diagram showing the overall configuration of the image forming system Software block diagram of image forming apparatus The figure which shows the structure in the controller unit of an image forming apparatus External view of input / output device of image forming apparatus External view of the operation unit of the image forming apparatus The figure which shows the structure in the operation part unit of an image forming apparatus. Data flow schematic of one embodiment of the present invention Flowchart of an embodiment of plate invention The figure which shows the conventional example of the rectangle drawing by overwriting The figure which shows the conventional example of the rectangle drawing by the overprint Diagram showing a conventional example of color calculation by overprint Diagram showing an example of color calculation by overprint The figure which shows the color calculation example of the overprint by this invention The figure which shows the raster operation mode with which the render of this invention is provided.

Claims (3)

  In a drawing apparatus that interprets a page description language and generates a bitmap image, a detection unit that detects an area in which overprinting is specified by the page description language, and a color specification by the page description language is simulated in a specific color space And overwriting the background color with the value of the color component generated by the simulating means in a color component in which the color value of each color component of the color designation is not 0. A drawing apparatus characterized by performing print drawing.   2. A color component in which a color value of each color component of the color designation is 0 is logically summed with a background color by a value of the color component generated by the simulating means. The drawing apparatus according to 1.   The drawing apparatus according to claim 1, wherein the color designation is based on four color components of CMYK.

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