JP2010023461A - Image output device, image output system, image output method, computer program, and recording medium - Google Patents

Abstract

An object of the present invention is to enable high-speed feeding control of recording paper in a band unit in an area where there is no printed image on the engine side, thereby improving the printing speed.
When an area without a print image in the paper feed direction is detected before printing on recording paper (steps S205 to S207), only paper feed is performed without printing (step S211). In the control method, an image area composed of one or more lines is set as one band, the print image area is set to a plurality of bands (step S201), digital image data is received, and presence / absence of print image data is detected in band units. When setting, a threshold value for detecting the presence or absence is set (step S201), the presence or absence of data necessary for image printing is determined according to the threshold value (steps S202 to S208), and the band is necessary for image printing. If there is no data to be printed, that is, if there is no data to be printed, the band is only fed and skipped.
[Selection] Figure 21

Description

  The present invention relates to an image output apparatus and an image output system such as a printer, a digital copying machine, a facsimile, and a digital multifunction peripheral that reproduce and output a digital image signal as a visible image on a recording medium, and an image executed by the image output apparatus. The present invention relates to an output method, a computer program for executing the image output method on a computer, and a recording medium on which the computer program is read and recorded so as to be executable.

  FIG. 30 shows an example of an image output apparatus that reproduces and outputs a digital image signal as a visible image on a recording medium. This image output apparatus is a digital multifunction machine having a plurality of functions such as a printer function, a copy function, and a facsimile function. Such a digital multi-function peripheral is generally called MFP (Multi Function Peripheral). This image output device is a wide-width inkjet type MFP, and includes a document feeder DF, an operation panel OPB, a scanner SCR, and a printer PTR. In the wide-width MFP, as standard sizes, copying up to A0 paper, a scanner application, and a printer application can be executed. Further, the special size corresponds to a long size, and a copy, a scanner application, and a printer application of A0 width 841 [mm] up to 15 [m] can be executed.

  FIG. 31 is a perspective view showing an appearance of an example of a printer that has been conventionally implemented. This printer is a wide-width inkjet printer, and includes an operation panel OPB and a print unit PTR. In this wide-width printer, a printer application up to A0 paper can be executed as a standard size, and the special size corresponds to a long size. The A0 width is 841 [mm] and the length is up to 15 [m]. The printer application can be executed.

  32 is a principal perspective view showing a schematic configuration of an ink jet print head unit which is an image forming unit of the MFP of FIG. 30 or the printer of FIG. In the figure, an image is formed on the recording paper supplied as the roll paper 33 with C (cyan), M (magenta), Y (yellow), and K (black) inks ejected from the inkjet head 31. The inkjet head 31 is conveyed left and right by a head conveyance belt 32 (moved in the main scanning direction), and after an image is formed on the recording paper, it is fed by a recording paper feeding roller 34 and a pressing roller 35 (in the sub scanning direction). Transport). An image is formed by repeating such movement in the main scanning direction and conveyance in the sub scanning direction.

  FIG. 33A shows the nozzle arrangement of the CMYK inkjet head 31 described above. Here, the CMYK nozzles 311, 312, 313, and 314 are arranged in two rows, and the distance between the nozzles is 0.042 [mm]. This is the distance between dots when the image resolution is 600 [dpi], that is, when 600 dots are formed per inch. Here, for each color of CMYK, nozzles indicated by the number of BLINE lines are arranged. Accordingly, in FIG. 32 described above, every time the inkjet head 31 is conveyed from left to right or from right to left, it is possible to transfer an image for the number of lines indicated by BLINE. When the image is full color, ink is ejected from the CMYK nozzles 311, 312, 313, and 314. Further, when the transfer image is monochrome, only the K color ink is ejected from the K color nozzle 314.

  In FIG. 33B, two black heads 314, K1 and K2, are arranged in the paper feed direction, and the number of transferred image lines during one print head transport in monochrome is larger than in full color. The print speed is increased by a factor of two. Since the transfer image is often formed in monochrome, increasing the print speed in monochrome by adding one head is advantageous in terms of performance as an MFP or printer.

  FIG. 34 shows image data C (cyan) for printing from an IMAC (image memory access control unit) 12 to a CDIC (compression / decompression and data interface control unit) 4 and IPP (image processing processor) 3 in a conventional image output apparatus. , M (magenta), Y (yellow), K (black) are transferred. Note that the IMAC 12, CDIC 4, and IPP 3 themselves correspond to the embodiments shown in FIGS. 1 and 3 to be described later, and the details are omitted here. In this example, the CMYK four colors are shown as the print image data. However, in actuality, the color plate may be increased for higher image quality, or an RGB image is transferred to the image processing processor IPP3. The color conversion from RGB to CMYK or the like may be performed. In addition, the transfer from the IMAC 12 to the CDIC 4 is performed in a time-sharing manner for images of the C, M, Y, and K color plates via the parallel bus. That is, 8-bit data for each color of C, M, Y, and K is transferred from the IMAC 12 to the CDIC 4, and the C, 4, IPP 3, the band FGATE (frame gate signal) and LSYNC (line synchronization signal) together with the C, 8-bit data is transferred for each color of M, Y, and K.

  FIG. 35 (a) shows an example of a print image. FIG. 35 (b) shows an area in which the print head of FIG. 35 (a) is printed by a single scan described above in FIG. Now let's call it a band, but it shows how this band is allocated. Here, for the sake of explanation, a case where the image of FIG. 35A is divided into 10 bands of band 1 to band 10 as shown in FIG. 35B is shown. Therefore, if the ink head of FIG. 32 has the nozzle arrangement of FIG. 33A, printing can be performed in 10 scans.

  FIG. 36 shows the transfer data I2C_C, I2C_M, I2C_Y, I2C_K from the IMAC12 to the CDIC4, the transfer data C2I_C, C2I_M, C2I_Y, C2I_K from the CDIC4 to the IPP3, the frame gate signal C21_FGATEB, and the line synchronization signal C21_. It is a timing chart which shows the relationship of output timing. These image data are transferred and printed as the data for each band shown in FIG.

  FIG. 37 is a block diagram showing a circuit for controlling the number of pixels in one line. First, at the start of printing, the load signal (LD_ONP) is asserted to the main scanning pixel number register (ONP) 361 to set the number of pixels in one line from the CPU of the process controller. At the start of data transfer for one line, the main scanning pixel number counter (PCNT) 360 is cleared by asserting its reset signal (RES_PCNT). Each time one pixel is transferred, INC_PCNT is asserted and the counter (PCNT) is incremented. The values of the main scanning pixel number register (ONP) 361 and the main scanning pixel number counter (PCNT) 360 are compared by the comparator (CMP) 362, and the value of the main scanning pixel number counter (PCNT) 360 is compared with the main scanning pixel number register ( When the LINE_END signal is asserted, the data transfer completion of one line is detected.

  FIG. 38 is a block diagram showing a circuit for controlling the number of lines of one recording sheet. First, at the start of printing, the load signal (LD_ONL) is asserted to the sub-scanning line number register (ONL) 371 to set the number of recording paper lines from the CPU. At the start of transfer of transfer image data, the sub-scanning line counter (LCNT) 370 is cleared by asserting the reset signal (RES_LCNT). Each time one line is transferred, INC_LCNT is asserted and the counter (LCNT) 370 is incremented. The values of the sub-scanning line number register (ONL) 371 and the sub-scanning line number counter (LCNT) 370 are compared by the comparator CMP372, and the value of the sub-scanning line counter (LCNT) is compared with the value of the sub-scanning line number register (ONL). When they coincide with each other and the PRINT_END signal is asserted, the completion of data transfer of one recording sheet is detected.

  FIG. 39 is a flowchart showing a control procedure during printing. A control procedure for controlling the data transfer shown in the timing chart of FIG. 36 with the circuits of FIGS. 37 and 38 will be described. In FIG. 39, when printing is started, the LD_ONL signal is activated and the number of output lines is set in the sub-scanning line number register (ONL) 371 (step 501). Next, the sub-scanning line counter (LCNT) 370 is cleared by asserting a reset signal (RES_LCNT) (step 502). Thereafter, C2I_FGATE is asserted (step 503), line data is received from the IMAC 12, C2I_LSYNCB and line data are output to IPP3, and INC_LCNT is asserted to increment the line counter (LCNT) 370 (step 504). The comparator (CMP) 372 compares the values of the sub-scanning line number register (ONL) 371 and the sub-scanning line number counter (LCNT) 370, and the value of the sub-scanning line counter LCNT is compared with the value of the sub-scanning line number register (ONL). If they coincide with each other and the PRINT_END signal is asserted (step 505-Yes) and the completion of data transfer of one sheet of recording paper is detected, C2I_FGATE is negated (step 506).

  For example, when the print image of FIG. 35 is printed in this way, the print image of the entire area is transferred from the IMAC 12 on the controller side to the engine side, and the print image of the entire area is processed as an ejection signal from the ink head. Become. Therefore, when printing is performed with the ink-jet head 31 for each band in FIG. 35B, since the band 1, the band 8, and the band 9 are actually white images, any color plate of CMYK from the ink-jet head 31 is used. Thus, no ink is ejected from the ink. Accordingly, since the image data of the band where ink is not ejected is also output to the inkjet head 31, the band where the print image is present and the band where the print image is not present have exactly the same operation. As described above, when printing an image with few print images, the print speed is the same as when there are many print images.

  On the other hand, as this type of technology, for example, the inventions described in Patent Documents 1 and 2 are known. Among them, the invention described in Patent Document 1 aims to provide a paper feed control system for image data printing that can shorten the time until printing is completed. In a printer that prints image data on printing paper, The position of the image data is received by a control command (including blank part length, image area length, paper size, etc.), the skip distance and the discharge distance are calculated from this control command, and only the skip distance is printed at the start of printing The paper is fed at high speed, the paper feed speed is adjusted to the printing speed at the adjustment distance, the print paper is fed to the blank part length at the cue position of the image data by the control command, and then the image data having the image area length is printed. It is going to end. With respect to the discharge distance of the remaining portion of the printing paper, the printing paper is again sent out at a high speed.

Further, the invention described in Patent Document 2 is intended to improve throughput by performing paper feeding only without driving an unnecessary shuttle even in the case of data in which blank dot lines continue. The purpose is that the CPU checks the data contents every time the print dot data is transferred for one dot line, and if it is blank dot line data, the CPU adds one value of the paper feed amount counter, On the other hand, if the data is dot line data other than blank, the CPU feeds the number of dot lines of the paper feed counter value all at once via the print control circuit, and then the CPU controls the print control circuit. Thus, printing for one stroke is performed as usual.
JP-A-8-142422 JP 2000-127510 A

  By the way, in the invention described in Patent Document 1, the position of the image data on the printing paper is determined by notifying the position of the image data by the control command to try to feed the paper at a high speed in the area where there is no image. Received as a control command (including blank part length, image area length, paper size, etc.) and calculated skip distance and discharge distance from this control command to realize high-speed paper feed control on the engine side I can't.

  In the invention described in the cited document 2, the CPU checks the blank line every time the print dot data is transferred for one dot line, and instructs the print control circuit (engine side) to feed the paper. It is not possible to achieve high-speed paper feed control.

  In any case, high-speed paper feeding cannot be performed in an area including no engine data on the engine side including the engine control unit. Therefore, when constructing such a system, it is necessary to design the controller on both the controller side and the engine side for each device to be controlled, and to set various control parameters. Not only does the setting cost increase, but the number of circuit boards to be prepared increases accordingly.

  Therefore, the problem to be solved by the present invention is to enable high-speed feed control of recording paper in band units in an area where there is no print image on the engine side, and to improve the print speed.

  In order to solve the above problems, the first means performs printing when a printing means for printing on the recording paper and an area without a print image in the paper feed direction is detected before printing on the recording paper. An image output device having only a paper feed control unit, and a band setting unit for setting an image area composed of one or more lines as one band and setting a print image area as a plurality of bands, When digital image data is received and the presence / absence of print image data is detected in band units, a threshold for detecting the presence / absence is set, and the presence / absence of data that requires image printing is determined according to the threshold. And a determination unit.

  The second means is characterized in that in the first means, an isolated point removing means for detecting an isolated point of the print image data and removing the isolated point before the determination by the determining means is provided. To do.

  The third means is characterized in that in the first or second means, there is provided a line number changing means for changing the number of lines constituting the band.

  When any one of the first to third means detects one or more bands that do not require image printing based on the detection result of the determination means, the fourth means controls image output to that effect. And a notification means for notifying the control means.

  The fifth means is characterized in that, in the fourth means, the notification means notifies the detection result by interruption.

  A sixth means is any one of the first to third means, wherein the control means for controlling the image output sets band identification information in band units for the image data receiving section for receiving the digital image data. The image data receiving unit in which the band identification information is set outputs image data of a band designated by the band identification information.

  A seventh means is the sixth means, wherein, when the band data specified by the band identification information starts from the line data that requires image printing, the image data receiving unit includes the band data including the line data. The image data of the area is output.

  According to an eighth means, in the sixth means, the image data receiving unit prints an image if the band data specified by the band identification information includes a line that does not require image printing to the middle of the band area. It is characterized by generating and outputting data that does not need to be printed by the number of lines that do not need to be printed.

  According to a ninth means, in the sixth means, the image data receiving unit, when all the band data specified by the band identification information is composed of data that does not require image printing, It generates and outputs data that does not require image printing.

  The tenth means is the one of the first to ninth means, wherein the determination means detects the presence or absence of print image data for each band, and when there is no print image, the paper feed control is performed; The determination means does not detect the presence / absence of the print image data for each band, and includes selection means for selecting when all the received images are printed.

  The eleventh means is characterized in that in any one of the first to tenth means, the printing means includes a print head for printing while moving in the main scanning direction.

  A twelfth means is the recording apparatus according to any one of the first to eleventh means, wherein the received digital image data is bitmap data of the entire area of the recording paper, and the band setting means is the recording image area. A plurality of bands are set for the entire area of the paper.

  The thirteenth means transmits the image output apparatus according to any one of the first to twelfth means and the digital image data read from the storage means or transmitted from the external apparatus via the network to the image output apparatus. And an image output system including a controller for controlling the entire system.

  The fourteenth means is one or more lines in a paper feed control method in which only paper feed is performed without printing when a region having no print image in the paper feed direction is detected before printing on the recording paper. A threshold for detecting the presence / absence of a print image area set as a plurality of bands, receiving digital image data, and detecting the presence / absence of print image data in band units And the presence or absence of data that requires image printing is determined according to the threshold value.

  A fifteenth means is characterized in that, in the fourteenth means, an isolated point of the print image data is detected and the isolated point is removed before the determination.

  A sixteenth means is characterized in that, in the fourteenth or fifteenth means, the number of lines constituting the band is changed.

  The seventeenth means is characterized in that, when one or more of the fourteenth to sixteenth means detect one or more bands that do not require image printing, a notification to that effect is sent to the control means that controls the image output. And

  In an eighteenth means according to any one of the fourteenth to sixteenth means, band identification information is set in band units for an image data receiving unit that receives digital image data, and the band identification information is set. The image data receiving unit outputs image data of a band designated by the band identification information.

  According to a nineteenth means, when a region without a print image is detected in the paper feed direction before printing on the recording paper, the computer executes a paper feed control method in which only paper feeding is performed without printing. In this computer program, a processing procedure for setting an image area composed of one or more lines as one band and a print image area as a plurality of bands, and receiving digital image data, and detecting the presence or absence of print image data in units of bands And a processing procedure for setting a threshold for detecting the presence / absence and determining the presence / absence of data necessary for image printing according to the threshold.

  The twentieth means is characterized in that the computer program according to the nineteenth means is recorded on a recording medium so as to be read and executed by a computer.

  In the embodiments described later, the printing means is the image forming unit 9 or the inkjet head 31, the paper feed control means is the ink output control unit 802 and the process controller 22, and the band setting means is the band line number register (BLINE) 51 and In the process controller 22, the judging means is in the skip control sections 400 and 600, the isolated point removing means is in the isolated point removing sections 407 and 605, and the line number changing means is in the band line number register (BLINE) 51 and the process controller 22. The control means for controlling the output is the process controller 22, the notification means is for the skip control sections 400 and 600, the image data receiving section is for the CDICs 4 and 6, the band identification information is for the Skip Enable signal, and the number of lines that do not require image printing. Is the count of the skip line counter (SLCNT) 65 The generation of the data that does not need to be printed as the output value is output to the function of the skip band number counter (NSKIP_BAND) 67, and the selection means corresponds to the threshold value register (THRESH) 60 and the set value of the register, The threshold value is stored in a threshold value register (THRESH) 60 and used.

  According to the present invention, it is possible to perform high-speed feeding control of recording paper in band units in an area where there is no print image on the engine side, and to improve the printing speed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Hereinafter, examples in the present embodiment will be described in comparison with conventional examples.
FIG. 1 is a block diagram illustrating a system configuration of an MFP as an image output apparatus according to the first embodiment. In FIG. 1, the MFP according to the present embodiment basically includes a controller unit CTR and an engine unit EGN. The engine unit EGN includes a reading unit 1, a sensor board unit (SBU-hereinafter referred to as SBU) 2, an image processor (IPP-hereinafter referred to as IPP) 3, an image data control unit (compression / decompression and data interface). Control unit: CDIC—hereinafter referred to as CDIC) 4, memory (MEM—hereinafter referred to as MEM) 7, video data control unit (VDC—hereinafter referred to as VDC) 8, image forming unit 9, process controller 22 RAM 23 and ROM 24 are provided. The process controller 22, the RAM 23, and the ROM 24 are connected to the above-described units via the serial bus 21.

  The controller unit CTR includes an image memory access control unit (IMAC-hereinafter referred to as IMAC) 12, a system controller (CPU) 13, a hard disk (hereinafter referred to as HDD) 14, and a memory module (hereinafter referred to as MEM). 15, an operation panel 17 and a ROM 18, and a network 16 is connected via a network I / F.

  The controller unit CTR and the engine unit EGN can transmit and receive data and commands between the IMAC 12 and the CDIC 4 via the parallel bus 11. The process controller 22 controls the MFP in cooperation with the system controller 13 via the CDIC 4 and the serial bus 21.

  FIG. 2 is a diagram showing the flow of image data in the system configuration of FIG. The operation of each functional module will be described along with the flow of image data.

  The reading unit 1 that optically reads an original condenses the reflected light of lamp irradiation on the original on a CCD as a light receiving element by a mirror and a lens. The CCD is mounted on the SBU 2, and the image signal converted into an electrical signal in the CCD is converted into a digital signal and then output from the SBU 2. The image signal output from the SBU 2 is transferred to the IPP 3, corrects signal deterioration (scanner signal deterioration) associated with quantization of the optical system and the digital signal, and is input to the CDIC 4. The CDIC 4 controls all image data transmission between the functional device and the data bus. The CDIC 4 performs communication between the SBU 2, the parallel bus 11, and the IPP 3 regarding the image data, and communication between the system controller 13 that controls the overall control and the controller that controls the process for the image data, in other words, the process controller 22 that controls the image output. . Each of the system controller 13 and the process controller 22 includes a CPU and executes respective controls.

  The data transferred from the IPP 3 to the CDIC 4 is sent from the CDIC 4 to the IMAC 12 via the parallel bus 11. Under the control of the system controller 13, the IMAC 12 performs access control of the image data and the MEM 15, development of print data of an external PC (personal computer) connected to the network 16, and compression / decompression of the image data for effective use of the memory. Is called. The data sent to the IMAC 12 is stored in the MEM 15 after data compression, and the stored data is read out as necessary. The flow (path) of this image data is indicated by an arrow A.

  The read data is expanded, returned to the original image data, and returned from the IMAC 12 to the CDIC 4 via the parallel bus 11. After the transfer from the CDIC 4 to the IPP 3, image quality processing and rendering processing by the IPP 3 and print head control by the VDC 8 are performed, and a reproduced image is formed on the recording paper in the image forming unit 9. Meanwhile, the IPP 3 uses the MEM 7 to execute the image quality process and the rendering process. The flow (path) of this image data is indicated by an arrow B.

  In the flow of image data indicated by paths A and B, the MFP functions are realized by the bus control by the parallel bus 11 and the CDIC 4. That is, in a situation where a plurality of jobs, for example, a copy function, a scanner function, and a printer output function operate in parallel, the system controller 13 and the process controller allocate the right to use the reading unit 1, the image forming unit 9, and the parallel bus 11 to the job. Control at 22. The process controller 22 controls the flow of image data, and the system controller 12 controls the entire system and manages the activation of each resource.

  The MFP function selection is selected and input from the operation panel 17, and processing contents such as a copy function and a scanner function are set. The system controller 13 and the process controller 22 communicate with each other via the parallel bus 11, the CDIC 4, and the serial bus 21. Data format conversion for data interface between the parallel bus 11 and the serial bus 12 is performed in the CDIC 4. In the scanner application, document image data read by the reading unit 1 and the SBU 2 is subjected to image quality processing by the IPP 3 and stored in the MEM 15 or the HDD 14 from the CDIC 4 via the parallel bus 11 and the IMAC 12, and then from the network 16 as necessary. The original image data is sent to a personal computer (PC) via.

  FIG. 3 is a block diagram illustrating a system configuration of a printer as an image output apparatus according to a modification of the first embodiment. In the printer configuration of FIG. 3, the functional module related to image reading is omitted from the MFP configuration of FIG. 1. That is, the reading unit 1 and the SBU 2 are omitted, and print data from the PC input via the network 16 is printed out. In FIG. 3, since the configurations of IPP and CDIC are different from those of the MFP, the reference numerals 5 and 6 different from those of the MFP are given, but the other configurations are the same as those of the MFP shown in FIG. Therefore, description of each overlapping part is omitted.

  FIG. 4 is a diagram showing the flow of image data in the system configuration of FIG. The operation of each functional module will be described along with the flow of image data.

  In FIG. 4, print processing instructed from a PC (personal computer) via a network is converted from printer description language to bitmap data by the system controller 13, and the converted bitmap data is stored in the MEM 15. This image data flow (path) is indicated by an arrow C. Thereafter, the data is transferred from the IMAC 12 to the CDIC 6 via the parallel bus 11. After the transfer from the CDIC 6 to the IPP 5, rendering processing by the IPP 5 and print head control by the VDC 8 are performed, and a print image is formed on the recording paper in the image forming unit 9. The flow (path) of this image data is indicated by an arrow D.

  Note that each configuration of the MFP illustrated in FIGS. 1 and 2 and the printer illustrated in FIGS. 3 and 4 has been conventionally implemented.

  FIG. 5 is a block diagram showing an outline of the configuration of the IPP for the MFP. The IPP 3 includes a scanner image processing unit 301, a command control unit 302, an image quality processing unit 303, and a rendering processing unit 304. Data is input from the input I / F 311 to the scanner image processing unit 301 and output from the output interface 312. Data is input from the input I / F 313 to the image quality processing unit 303 and output to the rendering processing unit 304. The rendering processing unit 304 is connected to the output I / F 314 and the MEMI / F 315, outputs the data rendered to the outside from the output I / F 314, stores the data in the MEM 15 via the MEMI / F 315, and is stored. Read the data.

  The read image is transmitted from the input I / F 311 of the IPP 3 to the scanner image processing unit 301 via the SBU 2. For the purpose of correcting deterioration of the read image signal, shading correction, scanner γ correction, MTF correction, and the like are performed. After the read image data correction processing is completed, the image data is transferred to the CDIC 4 via the output I / F 312.

  For output to the recording paper, image data from the CDIC 4 is received from the input I / F 313, and area gradation processing is performed in the image quality processing unit 302. After the image quality processing, the rendering processing unit 304 performs rendering processing according to the arrangement of the print heads via the external MEM 15 and outputs the data to the VDC 8 via the output I / F 314. Area gradation processing includes density conversion, dither processing, error diffusion processing, and the like, and mainly performs area approximation of gradation information. Once the scanner image processed image data is stored in the MEM 15, various reproduced images can be confirmed by changing the image quality processing. For example, the atmosphere of the reproduced image can be changed by changing the density of the reproduced image or changing the number of lines of the dither matrix. At this time, it is not necessary to read the image from the reading unit every time the processing is changed, and if the stored image is read from the MEM 15, different processing can be performed on the same data any number of times. In the case of a single scanner, scanner image processing and gradation processing are performed together and output to the CDIC 4. The command control unit 302 manages processing switching, processing procedure change, and the like.

  FIG. 6 is a block diagram showing a configuration of a conventional CDIC for MFP. The CDIC 4 for MFP includes an image data input unit 401, a data compression unit 402, a data conversion unit 403, a data expansion unit 404, an image data output control unit 405, and a command control unit 406. The data conversion unit 403 is a serial data interface 411. And connected to the outside via a parallel data interface 412.

  In the image data input control unit 401, data corrected by the scanner image by the IPP 3 is input. The input data is compressed by the data compression unit 402 in order to increase the transfer efficiency on the parallel bus, and is sent to the parallel bus 11 via the parallel data I / F 412. Image data input from the parallel data bus 11 via the parallel data I / F 412 is compressed for bus transfer and is expanded by the data expansion unit 404. The expanded image data is transferred from the image data output control unit 405 to the IPP 3. Further, the CDIC 4 has a parallel data and serial data conversion function. The system controller 12 transfers the data 11 to the parallel bus, and the process controller 22 transfers the data to the serial bus 21. Data conversion is performed for communication between the two controllers.

  FIG. 7 is a block diagram showing the configuration of the CDIC for the MFP according to this embodiment. The CDIC 4 for MFP according to the present embodiment is provided with a skip control unit 400 between the data decompression unit 404 and the image data output unit 405 with respect to the conventional CDIC 4 shown in FIG. It is the same as before. The skip control executed by the skip control unit 400 will be described later.

  FIG. 8 is a block diagram showing a schematic configuration of an IPP for a printer. The IPP 5 includes a rendering processing unit 501 and a command control unit 502, and further includes an input I / F 511, an output I / F 512, and a MEMI / F 513 that are connected to the rendering processing unit 501. In the IPP 5 configured as described above, image data input from the CDIC 6 via the input I / F 511 is subjected to rendering processing according to the arrangement of the print heads using the external MEM 15 via the MEMI / F 513. And output to the VDC 8 via the output I / F 512.

  FIG. 9 is a block diagram showing the configuration of a conventional printer CDIC. The printer CDIC 6 includes a data conversion unit 601, a data decompression unit 602, an image data output control unit 603, and a command control unit 604. The data conversion unit 601 is connected to the outside via a serial data interface 611 and a parallel data interface 612. It is connected.

  Print image data input to the data conversion unit 601 from the parallel data bus 11 via the parallel data I / F 612 is compressed for bus transfer and is expanded by the data expansion unit 602. The expanded image data is transferred from the image data output control unit 603 to the IPP 5.

  FIG. 10 is a block diagram showing the configuration of the printer CDIC according to this embodiment. The CDIC 6 for a printer according to the present embodiment has a skip control unit 400 provided between the data decompression unit 602 and the image data output control unit 603 with respect to the conventional CDIC 6 shown in FIG. Is the same as before. The skip control executed by the skip control unit 400 will be described later.

  FIG. 11 is a block diagram showing the configuration of the VDC. The VDC 8 includes an edge smoothing processing unit 801, an ink output control unit 802, and a data conversion unit 803. The data conversion unit 803 is connected to the outside via a serial data interface 811 and a parallel data interface 812. In the VDC 8, additional processing is performed on the input image data according to the characteristics of the image forming unit. That is, the input image data is subjected to dot rearrangement processing by the edge smoothing processing unit 801, and further, ink output control of the image signal for dot formation is performed by the ink output control unit 802, and the image data is created. The image unit 9 is output as a target. In addition to the conversion of image data, the data conversion unit 803 has a parallel data and serial data format conversion function, and can support communication between the system controller 13 and the process controller 22 even with the VDC 8 alone. The parallel data is input / output to / from the data conversion unit 803 via the parallel data I / F 812 and the serial data is input / output to the data conversion unit 803 via the serial data I / F 811.

  FIG. 12 is a block diagram showing the configuration of the IMAC. In the figure, the IMAC 12 includes a memory access control unit 1201, a data decompression unit 1202, a data conversion unit 1203, a data compression unit 1204, a video control unit 1205, and a line buffer 1206. The data conversion unit 1203 is a parallel data I / F 1212. The video control unit 1205 can communicate with the outside via the system controller I / F 1211, and receives data from the outside via the line buffer 1206.

  The parallel data I / F 1212 manages an image data interface with the parallel bus 11. In terms of configuration, it controls the storage / reading of image data to / from the MEM 15 and the development of code data input mainly from an external PC into the image data. The input code data is stored in the local area in the line buffer 1206. The code data stored in the line buffer 1206 is expanded into image data in the video control unit 1205 based on the expansion processing command from the system controller 13 input via the system controller I / F 1211. The developed image data or the image data input from the parallel bus 11 via the parallel data I / F 1212 is stored in the MEM 15. In this case, the data conversion unit 1203 selects image data to be stored, the data compression unit 204 performs secondary compression of the data in order to increase the memory usage efficiency, and the memory access control unit 1201 sets the address of the MEM 15. Image data is stored in the MEM 15 while being managed. When reading out the image data stored in the MEM 15, the memory access control unit 1201 controls the read destination address, and the data expansion unit 1202 expands the read image data. When the decompressed image data is transferred to the parallel bus 11, data transfer is performed via the parallel data I / F 1212.

  The feature of this embodiment is that skip control units 400 and 600 as shown in FIGS. Hereinafter, this skip control will be described in detail.

  FIG. 13A shows a region where there is a print image and a region where there is no print image in the sub-scanning line direction that is the paper feed direction with respect to the print image shown in FIG. FIG. 13B shows the band allocation divided into the 10 bands shown in FIG. 13A shown in FIG. 34B. Here, the band 1, the band 8, and the band 9 are areas where there is no print image, and if the area where there is no print image can be detected at high speed, the data of the band where there is no print image in the ink head is not output. It is considered that the printing speed can be improved by performing only paper feeding. Accordingly, the skip control units 400 and 600 shown in FIG. 7 or FIG. 10 each receive image data from the controller-side IMAC 12 at high speed, detect whether there is a print image for each band, and if there is no print image Notifies the process controller 22 to that effect. The process controller 22 does not scan the ink-jet head 31 for printing for a band having no print image, and performs only paper feeding. The band or the band width is set so as to correspond to the scanning width of the inkjet head 31 as shown in FIG. Therefore, the number of lines (BLINE) constituting the band is changed between the case of scanning in the state of FIG. 33A and the case of scanning in the state of FIG. The change in the number of lines will be described later.

  FIG. 14 is a timing chart showing image transfer timing when the skip control units 400 and 600 perform the above-described skip control with respect to the conventional image transfer of FIG. In FIG. 14, first, the CDICs 4 and 6 receive image data from the controller side IMAC 12, and the skip control units 400 and 600 in the CDICs 4 and 6 detect whether there is an image for printing. As a result, since there is no print image in the no print image area R1 at the leading edge of the recording paper, image transfer from the CDICs 4 and 6 to the subsequent IPP 3 is not performed. Next, when image data in the print image presence region R2 starts to be received, it is detected that there is a print image, and this data is transmitted from the CDICs 4 and 6 to the subsequent IPP 8, and finally ink is ejected from the printer head 31. An image is formed. The next print image absence region R3 performs the same operation as the leading edge print image absence region, and the last rear end print image presence region R4 has the same operation as the print image presence region R2 (see FIG. 33).

When the skip control is performed, the print speed of the area with the print image and the area without the print image is as follows.
The non-printed image area is a time when image data is received from the controller-side IMAC 12, detected that there is no printed image, and only paper feeding is performed. First, since the paper feed time is the paper feed motor speed, it is, for example, 500 [mm / s]. This indicates that 500 [mm] paper can be fed per second. On the other hand, the time for transferring the image data from the controller side IMAC 12 to the CDICs 4 and 6 and detecting whether or not there is an image is the time for reading the data from the controller side memory MEM15 or the time for reading the image data from the IMAC 12 via the parallel bus. It is affected by the latest time of receiving or detecting the presence / absence of an image.

When the data reception speed from the MEM 15 to the IMAC 12 is realized by an I / F of 533 [Mbps] with a 32-bit width, the reception speed is
32 x 533 x α / 8 [MB / s]
It becomes. Here, α is the access efficiency with the memory. For example, when 0.6 (60%), the memory read speed is 1279 [MB / S].

On the other hand, the transfer speed from the IMAC 12 to the CDICs 4 and 6 via the parallel bus 11 is the transfer speed of the parallel bus 11. Now, assuming that PCI [64 bits] is 33 [MHz] transfer and transfer efficiency is 0.7 (70%),
64 × 33M × 0.7 / 8
Becomes 184 [MB / S].

  Further, as the time for detecting the presence / absence of an image, assuming that the detection is realized by hardware, and 64 bits for one word of PCI reception are detected at one clock (100 [MHz]), 8 bytes are set to 10 [ns]. Since this can be realized by the data processing speed, it is 800 [MB / S].

  As described above, the data reception speed is 184 [MB / S] because the data transfer speed from the IMAC 12 to the CDICs 4 and 6 is the slowest.

  When this 184 [MB / S] is represented by the printing speed [mm / s], it is as follows.

Print speed = reception speed x 25.4 / (data amount per line x resolution)
Here, when the A0 size (841 [mm] × 1189 [mm]), the main scanning length 841 [mm], the resolution is 600 [dpi], and each pixel has 2 bits, the printing speed = 184 [MB / S] × 25. 4 / (4966 [Byte] x 600)
= 1644 [mm / s]
On the other hand, as described above, the speed of only paper feeding is 500 [mm / s], so the printing speed without image printing is 500 [mm / s] due to the influence of the lower speed.

  Next, the speed at the time of printing is estimated. This can be calculated as the sum of the travel time of the inkjet head 31 and the paper feed time. Now, assuming that the paper feed shown in FIG. 32, that is, the number of lines BLINE in the sub-scanning direction is 960 lines and the traveling speed of the inkjet head 31 in the main scanning direction is 800 [mm / s], the traveling time of the inkjet head 31 is as follows. It becomes like this.

Ink head travel time = 841 × 1000/800
= 1051 [ms]
Paper feed distance = 960 × 25.4 / 600
= 40.6 [mm]
Paper feed time = 40.6 × 1000/500
= 81.3 [ms]
Ink head travel time + paper feed time = 1051 + 81
= 1132 [ms]
From these, 40.6 [mm] can be printed at 1132 [ms], so the print speed when there is an image is as follows.

Print speed = 40.6 × 1000/1132
= 35.8 [mm / s]
Actually, it is about 30 [mm / s] after subtracting the overhead for control. From the above, the print speed can be calculated as 500 [mm / s] when there is no print image and 30 [mm / s] when there is a print image.

  FIG. 15 is a diagram showing an example of calculating the print image ratio and the print time in the skip control when the recording paper is A0 size (841 [mm] × 1189 [mm]) under the above conditions. The time without skip control is also shown. Here, the ratio of print images in the paper feed direction, that is, the sub-scan line direction, and the time required for printing are shown. When the print image ratio is 100%, the time is 39.2 seconds, and no skip occurs, so it is the same as when no skip control is performed. In the control with skip, it can be seen that the skip time increases as the print ratio decreases, so the print time decreases.

  FIG. 16 shows an example of improving the printing speed when there is no skip or when there is skip when the print speed when the print image ratio is 100% is 1.0. FIG. 16 shows that when the print image ratio is 60%, it is 1.6 times that when no skip is performed, when the print image ratio is 40%, 2.3 times that when no skip is performed, and when the print image ratio is 20%, 4.0 times when no skip is performed. It can be seen that the printing speed is doubled.

  In the print image, as shown in FIG. 13A, there are not a few cases where there is no print image at the leading and trailing edges of the paper. When there is no print image, skip control is performed. Thus, the printing speed can be improved. This enables the user to execute printing quickly and solves problems such as a long waiting time in front of the printer.

  FIG. 17 is a diagram illustrating a control state when skip control is performed by dividing the print image illustrated in FIG. 13B into the bands illustrated in FIG. FIG. 17A shows a state in which the processing of band 5 has been completed. The first column shows the band number (Band No.), which is 1 to 10 because there are 10 bands. The second column indicates the processing state (State), where “1” indicates that the band has been processed, and “0” indicates that the band is still unprocessed. The third column indicates whether or not there is a print image in the band as a result of detecting the image data of that band (Skip Enable). “0” indicates that there is a print image and cannot be skipped. “1” indicates that there is no print image. Indicates skippable. Therefore, the Skip Enable signal corresponds to band identification information that sets whether to output image data of the band.

  The first to third columns indicate the results of receiving and processing the print image. Next, the fourth and fifth columns indicate the image output state. The fourth column indicates whether or not the image output or skip processing has been completed (Out put End), “1” indicates the end of processing, and “0” indicates no processing. The fifth column indicates whether or not skip processing has been performed (Skip Exec), “1” indicates that skip processing has been executed, and “0” indicates that a print image has been output without skip processing.

  When the skip control is performed in this way and the print image of FIG. 13B is output, the print control state finally becomes as shown in FIG. Thus, by accumulating the detection and output state of the print image, it becomes possible to use the information for control, and it is possible to confirm what processing has been performed during printing. These are also important information for knowing the status of the failure by referring to it when the failure occurs.

  In order to execute the skip control, it is necessary to assign a band number to the print image data transferred from the controller side IMAC 12. FIG. 18 is a block diagram showing a circuit configuration for detecting a band number, and FIG. 19 is a flowchart showing a control procedure by this circuit. In FIG. 18, a band line number register (BLINE) 51 sets the number of lines constituting one band. This number of lines corresponds to the number of nozzles in the paper feed direction of the head unit shown in FIG. 33, and the number of lines that the ink head can print in one scan. The band line counter (BLCNT) 50 is a line counter that counts the number of lines in the band. NUM_BAND 53 is a band counter indicating a band number.

The control procedure of this circuit including input / output signals will be described with reference to FIG.
First, at the start of printing, the number of lines for one band is set from the process controller 22 by asserting the load signal (LD_BLINE) to the band line number register (BLINE) 51 (step S101). Next, when band data reception starts, the band line counter (BLCNT) 50 is cleared by asserting its reset signal (RES_BLCNT) (step S102). Then, whenever image data is transferred line by line, INC_BLCNT is asserted and the band line counter (BLCNT) 50 is incremented (step S103). The values of the band line number register (BLINE) 51 and the band line counter (BLCNT) 50 are compared by the comparator (CMP) 52, and the value of the band line counter (BLCNT) 50 is compared with the value of the band line number register (BLINE) 51. When they match, the band counter (NUM_BAND) 53 is counted up by asserting the BAND_END signal (step S104) (step S105), and the reset signal (RES_BLCNT) of the band line counter (BLCNT) 50 is asserted and cleared. (Step S102). Thereafter, by repeating this operation (steps S102, S103, S104, S105, S106), the value of the band counter (NUM_BAND) 53 indicates the band number.

  Next, as skip control, it is necessary to detect whether the print image data transferred from the controller side IMAC 12 can be skipped for each band. FIG. 20 is a block diagram showing a circuit configuration of a circuit that performs skip control for each band, and FIG. 21 is a flowchart showing a control procedure by this circuit.

  In FIG. 20, a threshold register (THRESH) 60 is a register for storing a threshold value for determining whether or not there is a print image, and a skip line counter (SLCNT) 65 counts the number of lines without a print image from the head of the band. The counter and band line number register (BLINE) 51 for storing the number of lines constituting the band.

A control procedure of this circuit will be described with reference to FIG. 21 together with input / output signals.
In FIG. 21, when a printing operation is started, a threshold is set from the process controller (CPU) 22 by asserting a load signal (LD_THRESH) of the threshold register (THRESH) 60. The band line number register (BLINE) 51 is set by asserting the load signal (LD_BLINE) of the band line number register (BLINE) 51. Then, the skip line counter (SLCNT) 65 is reset by asserting RES_SLCNT which is a reset signal of the skip line counter (SLCNT) 65 (step S201).

  Next, the line data is input to the comparator (CMP) 61 as DIN pixel by pixel. If the data is smaller than the threshold set by the threshold register (THRESH) 60, that is, if there is no print image, the comparator output (A ≦ B) is “0”, and the OR62 output is also “0”. It is stored in the register 63 (step S202). This value becomes the input of the OR 62 again. If the data is larger than the threshold value, that is, if there is a print image, the comparator output (A ≦ B) is “1”, the output of the OR 62 is also “1”, and this value is stored in the register 63. This value is also input to the OR 62 again.

  When the print data is expressed in multiple gradations, depending on the value of the image data, even if it is determined that there is no print, the transferred image may not be affected. In this case, by determining that there is no print image using a threshold value, the possibility of skipping can be increased and the print speed can be improved. For example, when one pixel is represented by 8 bits, the value of the pixel can take a value of 0-255. In this case, if “6” is set as the threshold value, no print image can be obtained when the pixel value is “5” or less. When the pixel value is represented by 0 to 255, even if “5” or less is not printed, the image formation is not affected, and the possibility of skipping is increased, so that the printing speed can be improved.

  Here, if “0” is set in the threshold register (THRESH) 60, the data DIN is 0 or more, so the output of the comparator (CMP) 61 becomes “1”, and there is always a print image. Therefore, it is possible to prevent the skip operation from being performed in this way. As a result, even if it is determined that there is no print image for all the lines constituting the band, the image data for extrusion for transferring the subsequent print data is forcibly output, or the skip control is turned on when a failure occurs. Alternatively, the cause of the failure can be easily pursued by turning it off. Further, when measuring the effect of skip control, skip control ON and skip control OFF can be selected, and the effect of skip control can be demonstrated to the customer by measuring the print speed of both.

  The operation in step S202 is executed for all the pixels constituting the line (step S203). For example, if the recording paper size is A0, the main scanning length is 841 [mm], and if this is output at a resolution of 600 [dpi], one line consists of 19866 pixels, and a print image is printed for all these 19866 pixels. The presence or absence will be detected.

  When the processing for one line of data is completed in this way, the presence or absence of a print image is successively detected for each pixel of one line (step S204). If there is no print image, the output of the register 63 (EXIST_IMG) is “ “0”, “1” if there is a print image even with one pixel, and if there is a print image, the process of step S209 is executed.

  If there is no print image, the process from step S202 to S204 is executed for all pixels in one line in step S205. When the detection of the presence / absence of the print image is completed for all the pixels in one line, the INC_SLCNT signal from the inverter 64 is asserted, and the skip line counter (SLCNT) 65 is incremented (step S206). Then, it is checked whether or not the processing from step S202 to step S206 has been executed for all the lines of the band (step S207). If there is a print image on the way, the process proceeds from step S204 to step S209. If detection of the presence / absence of a print image is completed for all the lines of the band and there is no print image, it is determined that the band being processed can be skipped (SKIP_BAND = 1) (step S208). On the other hand, if there is a print image in the line in step S204, it is determined that the band being processed cannot be skipped (SKIP_BAND = 0) (step S209). Note that there is no print image for the number of lines indicated by the skip line counter (SLCNT) 65 at the head of the band.

  Next, an interrupt signal is output to the CPU of the process controller 22 to notify whether or not the band being processed can be skipped (step S210), and the process controller 22 in the ink output control unit 802 indicates the band area only when the band skip is possible. Is carried out (step S211).

  The control from step S202 to step S211 is executed for all the bands, and when the processing for all the bands is completed, the printing on the recording paper is completed (step S212).

  In the example of FIG. 20 and FIG. 21, the presence / absence of an image and paper feeding are performed one band at a time. However, when a band without a print image continues, paper is fed together after detecting the presence of a print image. To do. FIG. 22 is a block diagram showing a circuit configuration of a circuit that skips a plurality of bands together, and FIG. 23 is a flowchart showing a control procedure by this circuit.

In the circuit of FIG. 22, a skip band counter (NSKIP_BAND) 67 is added after the comparator (CMP) 66 with respect to the circuit of FIG. Other parts are the same as those in FIG. Hereinafter, the control procedure by the circuit of FIG. 22 will be described with reference to FIG. 23 together with input / output signals.
In FIG. 23, when the printing operation is started, a threshold is set from the process controller (CPU) 22 by asserting a load signal (LD_THRESH) of the threshold register (THRESH) 60. The band line number register (BLINE) 51 is set by asserting the load signal (LD_BLINE) of the band line number register (BLINE). Then, the skip line counter (SLCNT) 65 is reset by asserting RES_SLCNT which is a reset signal of the skip line counter (SLCNT) 65, and the reset signal (RES_NSKIP_BAND) of the skip band number counter (NSKIP_BAND) 67 is asserted. The skip band number counter (NSKIP_BAND) 67 is cleared (step S301).

  From step S302 to step S308, the same processing as in step S202 to step S207 in FIG. 21 is executed. ) 67 is incremented. Thereafter, in order to detect whether the next band can be skipped, the process returns to step S202, and the subsequent processing is repeated. If there is a print image in the line in step S204, the process proceeds to step S309, an interrupt is transmitted to the process controller (CPU) 22, and the number of skippable bands (NSKIP_BAND) is notified. Next, the ink output control unit 802 performs paper feed control for the number of skip bands (step S310).

  The control from step S302 to step S310 is executed for all the bands, and when the processing for all the bands is completed, the printing on the recording paper is completed (step S311).

  By controlling in this way, when a band without a print image continues, it is detected until there is a print image and then the paper is fed together, so there is no need to control each band, thereby further printing. Speed improvement can be realized.

  24 is a block diagram showing a circuit configuration of a circuit for outputting an image from the skip control units 400 and 600 of the CDICs 4 and 6 to the subsequent IPPs 3 and 5 via the image data output control units 405 and 603, and FIG. It is a flowchart which shows the control procedure of the circuit.

  In FIG. 24, NBAND_OUT 70 is an output band number designation register, and the image data of the band set in this register is output from the process controller (CPU) 22. If the band number set by the process controller (CPU) 22 is a skippable register, data “0” indicating no print image is output as the image data of the band area. The line counter (BLOCNT) 71 is a counter that counts the output lines of the band. A line output counter (LOCNT) 74 is a counter that counts the number of line outputs on the entire surface of the recording paper.

  In the control by the circuit, as shown in FIG. 25, when the printing operation is started, the line output counter (LOCNT) 74 is cleared by asserting the reset signal (RES_LOCNT) of the line output counter (LOCNT) 74 ( Step S401). Next, the band number for data output from the process controller (CPU) 22 is set in the output band number command register (NBAND_OUT) 70. Further, RES_BLOCNT which is a reset signal of the line counter (BLOCNT) 71 is asserted and cleared. Thereafter, band start (BS), which is activation of band data output, is asserted (step 402).

  Thereafter, based on the band number (NBAND_OUT) set by the process controller (CPU) 22 and the table shown in FIG. 17 described above, the data of the set band number can be skipped, that is, whether there is no print image, cannot be skipped, That is, it is determined whether there is a print image. In the table of FIG. 17, skip enable / disable can be determined by the Skip Enable value for the set band number (step S403), and the value of the skip line counter (SLCNT) 65 of FIG. 20 or FIG. That is, it is detected whether or not the head line of the band is a line with a print image (step S404). If the first line has a print image, the process proceeds to step S407. If there is a line having no print image at the head of the band, the process proceeds to step S405.

  In step S405, “0” data is output for one line as no-print image data (white image line data). Thereafter, the line counters (BLOCNT, LOCNT) 71 and 74 are incremented. Then, it is determined whether or not line data without a print image is output by the value of the skip line counter (SLCNT) 65 (ZERO_LINE_END?), And when it is output, the process proceeds to step S407.

  In step S407, line data with a print image is output. Thereafter, the line counters (BLOCNT, LOCNT) 71 and 74 are incremented, and whether or not all the data of the band designated in step S408 has been output BAND_OUT_END? (BLINE == BLOCNT?) Is determined. If all the data has not been output yet, the print image data is continuously received from the controller side IMAC 12, and when the output of all the band data is completed, whether or not all the line data of the recording paper has been output PRINT_END? ( LOCNT?) Is determined (step S411). If it is determined that all line data has not yet been output, the process returns to step S402 and the subsequent processing is repeated. If it is output, the process ends. That is, printing on the recording paper is completed.

  In step S403, if there is no print image in the set band, white line data ("0" data) is output for one line. Thereafter, the line counters (BLOCNT, LOCNT) 71 and 74 are incremented (step S409). Whether or not all data of the designated band has been output BAND_OUT_END? (BLINE == BLOCNT?) Is determined (step S410), and if all the data has not been output yet, the process returns to step S409 to execute the process of step S409, and the output of all the band data has been completed. Whether or not all line data of the recording paper has been output PRINT_END? ( LOCNT?) Is determined (step S411). Based on this determination, the process returns to step S402 as described above, or the process ends. That is, printing on the recording paper is completed.

  The configuration of the MFP and the printer or the inkjet head 31, the transfer of image data from the IMAC 12 to the CDICs 4 and 6, and the transfer method of the image data transferred from the CDICs 4 and 6 to the IPPs 3 and 5 are as described in the background art. is there.

  In this embodiment, an isolated point removal function is added to the first embodiment in addition to the skip control function. 26 and 27 are block diagrams showing the CDIC of this embodiment. FIG. 26 shows a configuration in which an isolated point removing unit 407 is added before the skip control unit 400 of the MFP CDIC 4 in FIG. The configuration in which the isolated point removing unit 605 is added to the preceding stage of the skip control unit 600 of the printer CDIC 6 is shown. Other parts are configured in the same manner as in the first embodiment and function in the same manner.

The isolated point removal function will be described below.
There may be a small isolated point that does not make sense as an image in a read image or print image of a document. When skip control is performed in the first embodiment, if there is such an isolated point, a band including the isolated point cannot be skipped. If this isolated point has no meaning as an image, the band can be skipped by removing this isolated point, and the printing speed can be improved.

  For example, consider a case where there are four isolated points D1, D2, D3, and D4 as shown in FIG. 28A. When this is divided into 10 bands as described above, it is as shown in FIG. 28B. Since the skip process cannot be performed when there is a print image in the divided band, only the band 8 can be skipped in the example of FIG. 28B. This reduces the efficiency of skip processing.

  Therefore, isolated point removal processing is performed on the image of FIG. 28A. FIG. 18C is a printed image after the isolated point removal process is performed. Similarly, when this image is divided into 10 bands, it becomes as shown in FIG. 28D, and skipping is possible in 3 bands, band 1, band 8, and band 9. Compared to the case of FIG. 28B in which isolated point removal is not performed, it can be seen that the number of bands that can be skipped is increased by two.

  The isolated point removal itself is a known process, but this process will be briefly described here. Now, as shown in FIG. 28E, the image is considered as a 5 × 5 matrix, and the pixel of interest is a P (3, 3) pixel at the center position. With reference to the values of the pixels around the pixel of interest P (3, 3), if the following expression holds, the pixel of interest (3, 3) is determined to be an isolated point and is removed, ie, a white image without a print image .

P (3,3) >> (ΣP (x, y) −P (3,3)) {x = 1 to 5, y = 1 to 5}
This indicates that the pixel of interest P (3,3) is considerably larger than the sum of the values of the surrounding pixels (ΣP (x, y) −P (3,3)), and satisfies the requirement for an isolated point. It will be.

  FIG. 29 is a flowchart showing a control procedure in the case of outputting an image by performing an isolated removal process and a skip process. This flowchart is obtained by adding isolated point removal processing to step S202 of FIG. That is, when the printing operation is started, the threshold is set from the process controller (CPU) 22 by asserting the load signal LD_THRESH of the threshold register THRESH60. The band line number register (BLINE) 51 is set in the band line number register (BLINE) 51 by asserting the load signal LD_BLINE of the band line number register (BLINE) 51. Then, the skip line counter SLCNT65 is reset by asserting RES_SLCNT which is a reset signal of the skip line counter SLCNT65 (step S201).

  Next, the line data is input to the comparator CMP61 as DIN pixel by pixel. If the data is smaller than the threshold set by the threshold register THRESH 60, that is, if there is no print image, the comparator output (A ≦ B) is “0”, the output of the OR 62 is also “0”, and this value is stored in the register 63. Stored (step S202). This value becomes the input of the OR 62 again. If the data is larger than the threshold value, that is, if there is a print image, the comparator output (A ≦ B) is “1”, the output of the OR 62 is also “1”, and this value is stored in the register 63. This value is also input to the OR 62 again. At that time, isolated point removal is performed. The isolated point removal is determined by applying the above formula to the target pixel P for the 5 × 5 matrix in FIG. 28E using a line memory for 5 lines.

  After performing the isolated removal in this way, the skip processing after step S203 is executed, the control from step S202a to step S211 is executed for all the bands, and when the processing for all the bands is finished, Printing on the recording paper is completed (step S212). In addition, since the process of step S203-211 is the same as each step of FIG. 21, description is abbreviate | omitted.

  Further, the isolated point removal process can be executed by providing a process step before the step S202a. In this case, the processing from the previous stage to step S211 is repeated.

  By performing isolated point removal in this way, it is possible to increase the skippable band and improve the printing speed.

  Other parts not specifically described are configured in the same manner as in the first embodiment and function in the same manner.

As described above, according to the present embodiment, the following effects can be obtained.
1) When the presence / absence of data that requires image printing is detected in band units, a threshold value for the determination is provided, and the presence / absence of data that requires image printing is determined according to this threshold value. When multi-tone is expressed, depending on the value of the image data, even if it is determined that there is no printing, there is no effect on the transferred image. As a result, it is possible to enlarge the band to be skipped based on the presence / absence of print data for each band, thereby improving the printing speed.

2) When detecting the presence / absence of data that requires image printing in band units, isolated point removal is performed before performing the process of detecting the presence / absence of data that requires image printing (step S202a). When it is determined that the data is an isolated point, if the print data does not affect the transferred image even if it is determined that there is no printing, the isolated point can be removed and it can be determined that there is no printed image. As a result, the band to be skipped can be enlarged, and the print speed can be improved.

3) Since the number of lines in the paper feed direction constituting the band can be changed by a band line number register (BLINE) 51, for example, even when the number of ink heads used for color transfer and monochrome transfer is changed. In addition, it is possible to improve the printing speed in each print mode during color transfer or monochrome transfer.

4) When one or more bands that do not require image printing are detected, this is notified by an interrupt to the CPU of the process controller 22 that controls image output by the skip control units 400 and 600. It is possible to quickly notify the process controller 22 that a band that does not require image printing has been detected, and it is possible to minimize the time interval between controls, thereby improving the printing speed.

5) The process controller 22 that controls the image output apparatus outputs band identification information (Skip) for output to the CDICs 4 and 6 that are image data receiving units that receive print images in band units from the IMAC 12 on the system controller 13 side. When the specified band identification information includes a print image (Skip Enable = “0”), the CDIC 4 and 6 output a print image of the band, and an identification signal ( When Skip Enable = “1”) is set, data without a print image can be output. Therefore, when there is image data after CDIC 4 and 6, band data without a print image is output. By outputting, band data with a print image can be pushed out to the subsequent stage. Further, when data without print data is necessary for adjusting the ink head, these image data can be easily obtained.

6) When the output band data specified by the band identification information starts from the line data that requires image printing, the CDICs 4 and 6 output the band region image data including the line data, and the band identification information If the output data of the specified band includes lines that do not require image printing to the middle of the band area, data that does not require printing is generated and output for the number of lines that do not require image printing. If the output band data specified by (Skip Enable) is composed entirely of data that does not require image printing, the data that does not require image printing for that band area is generated and output. When there is a line without a print image before the print image, data without a print image can be output, and subsequently data with a print image can be output. As a result, it is possible to normally perform printing on recording paper, and to realize band skip control. Further, even when all the lines constituting the band are determined to have no print image, it is possible to generate image data that does not need to be printed in order to transfer the subsequent print data.

7) When digital image data is received from the IMAC 12, the presence or absence of print image data is detected for each band, and when a band that does not require image printing is detected, that fact is transferred to the video data control unit 8. The ink output control unit 802 of the video data control unit 8 does not print the image for the band area, but only performs paper feeding or outputs all image data without detecting the presence or absence of the print image. Therefore, it is possible to easily pursue the cause of the failure by switching between ON and OFF of the skip control in the skip control units 400 and 600 when a failure occurs. Further, it is possible to realize the evaluation of the printing speed by switching between ON and OFF of the skip control, and it is possible to confirm and present the effectiveness of the skip control.

8) On the engine (ENG) side, only the bitmap data of the entire area of the recording paper is obtained as digital image data from the controller (CNT) side, and a skippable area is determined for the area divided into a plurality of bands. Since only the paper feed control is performed, high-speed printing is possible.

9) On the controller (CNT) side, it is only necessary to transmit bitmap data of the entire recording paper area as digital image data to the image data control unit (CDIC) on the engine (ENG) side. Regardless of the formation method, the same controller configuration can be obtained, and compatibility with other models is facilitated.

10) The controller (CNT) side configuration may be the same controller configuration regardless of the engine side model or the image forming method. For example, an electrophotographic image output device and a serial head type image such as an ink jet method are used. The output device can also be handled by the controller (CNT) having the same configuration.

  In addition, this invention is not limited to this embodiment, It cannot be overemphasized that all the technical matters contained in the technical idea described in the claim are object.

1 is a block diagram showing a system configuration of an MFP as an image output apparatus according to Embodiment 1 of the present invention. It is a figure which shows the flow of the image data in the system configuration | structure of FIG. FIG. 6 is a block diagram illustrating a system configuration of a printer as an image output apparatus according to a modification of the first embodiment. It is a figure which shows the flow of the image data in the system configuration | structure of FIG. FIG. 2 is a block diagram illustrating an outline of a configuration of an IPP for MFP. It is a block diagram showing a configuration of a conventional CDIC for MFP. 1 is a block diagram illustrating a configuration of a CDIC for an MFP according to Embodiment 1. FIG. It is a block diagram which shows schematic structure of IPP for printers. It is a block diagram which shows the structure of the conventional CDIC for printers. 1 is a block diagram illustrating a configuration of a printer CDIC according to a first embodiment. FIG. It is a block diagram which shows the structure of VDC. It is a block diagram which shows the structure of IMAC. It is a figure which shows the blank part and band allocation of the recording paper in a printing image. It is a timing chart which shows the timing of the image transfer at the time of performing skip control in a skip control part. FIG. 10 is a diagram illustrating an example of calculating a print image ratio and print time in skip control of A0 size recording paper. It is a figure which shows the example of the print speed improvement at the time of skipping when there is no skip, or when the print speed when the print image ratio is 100% is 1.0. It is a figure which shows the control state when dividing the print image shown in FIG.13 (b) into the band shown in the figure, and performing skip control. It is a block diagram which shows the circuit structure which detects a band number. It is a flowchart which shows the control procedure by the circuit of FIG. It is a block diagram which shows the circuit structure of the circuit which performs skip control for every band. It is a flowchart which shows the control procedure by the circuit of FIG. It is a block diagram which shows the circuit structure of the circuit which skips several bands collectively. It is a flowchart which shows the control procedure by the circuit of FIG. It is a block diagram which shows the circuit structure of the circuit for outputting an image to IPP of a back | latter stage from a skip control part via an image data output control part. It is a flowchart which shows the control procedure of the circuit of FIG. FIG. 9 is a block diagram illustrating a configuration of a CDIC for MFP according to a second embodiment, in which an isolated point removing unit is added to the preceding stage of the skip control unit in FIG. 7. FIG. 11 is a block diagram illustrating a configuration of a printer CDIC according to a second embodiment, and is a diagram in which an isolated point removing unit is added to the preceding stage of the skip control unit of FIG. 10. FIG. 6 is a diagram illustrating an example of a state where an isolated point exists in a blank portion of a printed image. FIG. 29B is a diagram illustrating a state in which 10 bands are assigned to FIG. 28A and skipping is not possible. It is a figure which shows the printing image after removing an isolated point from FIG. 28A. It is a figure which shows the state which allocates 10 bands with respect to FIG. 28C, and cannot skip. It is a figure which shows the relationship of the attention pixel and matrix at the time of an isolated point removal process. It is a flowchart which shows the control procedure in the case of outputting an image by performing an isolated removal process and a skip process. It is a figure which shows an example of the image output apparatus (MFP) which reproduces | regenerates and outputs the digital image signal implemented conventionally as a visible image on a recording medium. It is a perspective view which shows the external appearance of an example of the printer implemented conventionally. FIG. 32 is a perspective view of a principal part showing a schematic configuration of an ink jet print head unit which is an image forming unit of the MFP of FIG. 30 or the printer of FIG. 31; It is a figure which shows nozzle arrangement | positioning of the inkjet head of FIG. It is a block diagram which shows the example in the case of transferring the image data for printing from IMAC in CDIC and IPP in the conventional image output apparatus. It is a figure which shows the allocation state of the band at the time of writing with a printing image and an inkjet head. FIG. 35 is a timing chart showing output timings of transfer data from IMAC to CDIC, transfer data from CDIC to IPP, a frame gate signal, and a line synchronization signal in FIG. It is a block diagram which shows the circuit which controls the pixel number of 1 line. It is a block diagram showing a circuit for controlling the number of lines of one sheet of recording paper. FIG. 39 is a flowchart showing a control procedure during printing in which the data transfer shown in the timing chart of FIG. 36 is controlled by the circuits of FIGS. 37 and 38. FIG.

Explanation of symbols

1 Reading unit 2 SBU
3,5 IPP
4,6 CDIC
7,15 MEM
8 VDC
9 Image forming unit 11 Parallel bus 12 IMAC
13 System controller (CPU)
21 Serial bus 22 Process controller (CPU)
31 Inkjet head 51 Band line number register (BLINE)
60 Threshold register (THRESH)
65 Skip line counter (SLCNT)
67 Skip band counter (NSKIP_BAND)
400,500 Skip control unit 407,605 Isolated point removal unit 802 Ink output control unit BLINE Number of lines constituting the band CTR controller unit EGN engine unit

Claims (20)

Printing means for printing on recording paper;
Before printing on the recording paper, when a region without a print image in the paper feed direction is detected, paper feed control means for performing only paper feed without printing;
In an image output apparatus having
Band setting means for setting an image area composed of one or more lines as one band and setting the print image area as a plurality of bands;
When digital image data is received and the presence or absence of print image data is detected in band units, a threshold for detecting the presence or absence is set, and the presence or absence of data necessary for image printing is determined according to this threshold Means,
An image output apparatus comprising: The image output apparatus according to claim 1,
An image output apparatus comprising: an isolated point removing unit that detects an isolated point of the print image data and removes the isolated point before the determination by the determining unit. The image output apparatus according to claim 1 or 2,
An image output apparatus comprising line number changing means for changing the number of lines constituting the band. The image output device according to any one of claims 1 to 3,
An image having a notification means for notifying to the control means for controlling the image output when one or more bands that do not require image printing are detected based on the detection result of the determination means. Output device. The image output apparatus according to claim 4, wherein
The image output apparatus characterized in that the notification means notifies the detection result by interruption. The image output device according to any one of claims 1 to 3,
The control means for controlling image output sets band identification information in band units for the image data receiving unit that receives the digital image data,
The image output device having the band identification information set outputs image data of a band designated by the band identification information. The image output apparatus according to claim 6.
When the image data of the band specified by the band identification information starts from line data that needs image printing, the image data receiving unit outputs image data of a band region including the line data. Image output device. The image output apparatus according to claim 6.
When the image data of the band specified by the band identification information includes lines that do not require image printing to the middle of the band area, the image data receiving unit needs to print only the number of lines that do not require image printing. An image output apparatus that generates and outputs data that is not included. The image output apparatus according to claim 6.
When the image data of the band specified by the band identification information is all composed of data that does not need image printing, the image data receiving unit generates data that does not require image printing for the band area. An image output apparatus that outputs the image data. The image output device according to any one of claims 1 to 9,
The determination means detects the presence or absence of the print image data for each band, and if there is no print image, the paper feed control is performed, and the determination means does not detect the presence or absence of the print image data for each band, An image output apparatus comprising means for selecting when all received images are printed. The image output device according to any one of claims 1 to 10,
An image output apparatus comprising a print head for printing while the printing means moves in the main scanning direction. The image output device according to any one of claims 1 to 11,
The received digital image data is bitmap data of the entire area of the recording paper,
The image output apparatus according to claim 1, wherein the band setting means sets a plurality of bands for the entire area of the recording paper which is a print image area. The image output apparatus according to any one of claims 1 to 12,
A controller unit for reading the digital image data read from the storage means or transmitted from the external device via the network to the image output device, and for controlling the entire system;
An image output system comprising: In the paper feed control method in which, when printing on the recording paper, an area without a print image is detected in the paper feed direction, printing is not performed and only paper feed is performed.
The image area composed of one or more lines is set as one band, and the print image area is set as a plurality of bands.
When digital image data is received and the presence / absence of print image data is detected in band units, a threshold for detecting the presence / absence of the image is set, and the presence / absence of data necessary for image printing is determined according to the threshold. An image output method characterized by the above. The image output method according to claim 14.
An image output method comprising: detecting an isolated point of the print image data and removing the isolated point before performing the determination. The image output method according to claim 14 or 15,
An image output method, wherein the number of lines constituting the band is changed. The image output method according to any one of claims 14 to 16,
An image output method characterized in that when one or more bands that do not require image printing are detected, a notification to that effect is sent to a control means that controls image output. The image output method according to any one of claims 14 to 16,
Set band identification information for the image data receiver that receives print images in band units,
The image data receiving unit in which the band identification information is set outputs image data of a band designated by the band identification information. In a computer program for executing a paper feed control method in which a paper feed control method for performing only paper feed without performing printing when a region without a print image in the paper feed direction is detected before printing on recording paper,
A processing procedure for setting an image area composed of one or more lines as one band and setting a print image area as a plurality of bands;
When digital image data is received and the presence / absence of print image data is detected in band units, a threshold value is set for detecting the presence / absence of the print image data, and the presence / absence of data necessary for image printing is determined according to the threshold value Procedure and
A computer program comprising:   20. A recording medium on which the computer program according to claim 19 is recorded by being read and executable by a computer.

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