JP2013065955A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively perform a white skip processing even when printing a background pattern image.SOLUTION: An image forming apparatus includes: detecting means for obtaining image data, and detecting an area where there is no image to be printed in a sub-scanning direction; calculating means for calculating a size of a printing area in the sub-scanning direction on the basis of the area detected by the detecting means; and composing means for varying magnification of a background pattern image to be printed overlapped with an image in accordance with the size of the printing area calculated by the calculating means, and composing the background pattern image after varying the magnification with the image data.

Description

  The present invention relates to an image forming apparatus that simplifies and omits processing of an area where there is no image to be printed.

  In an image forming apparatus, when an image to be printed is smaller than a paper surface, a technique for improving a printing speed by simplifying or omitting processing of an area where there is no image to be printed is already known. This technique is also called white skip processing.

  As a white skip technique, for example, Patent Document 1 describes that high-speed feed control of recording paper is performed on a band basis in an area where no print image is present on the engine side.

  Here, in order to prevent unauthorized copying of a document, there is a technology related to tint block printing that prints a tint block image on a printing paper.

  When the tint block printing is performed by an apparatus that performs white skip processing according to the prior art, when the tint block image is larger than the print image, only the portion corresponding to the size of the tint block image can be subjected to the white skip processing. Therefore, when the actual print image is smaller than the copy-forgery-inhibited pattern image, there is a problem that the effect of the white skip processing is reduced.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can effectively perform white skip processing even when a copy-forgery-inhibited pattern image is printed.

  An image forming apparatus according to an aspect of the invention acquires image data, detects a region where there is no image to be printed in the sub-scanning direction, and detects a region in the sub-scanning direction based on the region detected by the detecting unit. A calculation unit that calculates a size of the print area; and a scale pattern image that is superimposed on the image is scaled according to the size of the print area that is calculated by the calculation unit, and the scale pattern image that has been scaled is Synthesizing means for synthesizing the image data.

  According to the present invention, white skip processing can be effectively performed even when a tint block image is printed.

1 is a block diagram illustrating an example of a configuration of an image forming apparatus according to an embodiment. The figure for demonstrating a white skip area | region. The figure for demonstrating tint block composition. The block diagram which shows an example of a structure of a controller control part. The block diagram which shows an example of a structure of an engine control part. The block diagram which shows an example of a structure of 5CH process means. The figure which shows an example of a printing result (the 1). The figure for demonstrating the repetition of a tint block image. The figure which shows an example of a printing result (the 2). The flowchart which shows an example of a process of a controller control part. The flowchart which shows an example of a process of an engine control part. 5 is a flowchart illustrating an example of a background pattern synthesis process.

  Embodiments according to the present invention will be described below with reference to the accompanying drawings.

[Example]
<Configuration>
FIG. 1 is a block diagram illustrating an example of a configuration of an image forming apparatus 100 in the embodiment. An image forming apparatus 100 shown in FIG. 1 includes an engine board 101, a controller board 102, a reading unit 103, a writing unit 104, and a controller / engine I / F (interface) 105. The controller / engine I / F 105 connects the engine board 101 and the controller board 102, and an I / F such as PCI (Peripheral Component Interconnect) or PCI Express is used.

  The engine board 101 controls engine units such as the reading unit 103 and the writing unit 104. The engine board 101 includes, for example, an engine CPU (Central Processing Unit) 111, a reading control unit 112, an engine control unit 113, and a writing control unit 114.

  The engine CPU 111 controls each unit or performs various data calculations, and controls the engine control unit 113, for example.

  The reading unit 103 performs a process of reading an original during a copying operation as a scanner, for example, and generating image data. The reading unit 103 inputs the read image data to the reading control unit 112.

  The reading control unit 112 acquires image data read by the reading unit 103 and outputs the image data to the engine control unit 113.

  The engine control unit 113 outputs the image data acquired from the reading control unit 112 to the controller board 102 via the controller / engine I / F 105. The engine control unit 113 performs a writing process on the image data acquired from the controller board 102 via the controller engine I / F 105. The engine control unit 113 outputs the image data after the writing process to the writing processing unit 114. As a process for writing, for example, there is a tint block synthesis process.

  The writing processing unit 114 outputs the image data acquired from the engine control unit 113 to the writing unit 104.

  The writing unit 104 acquires image data from the writing control unit 114 and prints the image data on a recording medium. The recording medium is, for example, a recording sheet.

  The controller board 102 controls the entire image forming apparatus 100. The controller board 102 includes, for example, a controller CPU 121, a controller control unit 122, and a storage unit 123.

  The controller CPU 121 controls each unit or performs various data calculations, and controls the controller control unit 122, for example.

  The controller control unit 122 accumulates the image data acquired from the engine board 101 via the controller / engine I / F 105 in the storage unit 123. Further, the controller control unit 122 performs image processing on the acquired image in accordance with the application.

  For example, in the case of copy processing, the controller control unit 122 performs image processing necessary for copying. When the image processing is completed, the controller control unit 122 outputs the processed image data to the engine board 101 via the controller / engine I / F 105 as image data for writing.

  The storage unit 123 is a memory such as a RAM (Random Access Memory) or a ROM (Read On Memory), and stores a copy-forgery-inhibited pattern image, image data acquired from a memory controller 402 described later, and the like.

  The reading control unit 112, the engine control unit 113, the writing control unit 114, and the controller control unit 122 can be implemented by, for example, an LSI (Large Scale Integration).

  The above processing is the image processing operation in general copying. On the other hand, in this copy process, various ideas have been made to improve performance and efficiency. One of the devices is, for example, white skip processing. The white skip process is a process for improving the printing speed by simplifying or omitting the process of an area where there is no image to be printed when the image to be printed is smaller than the paper surface.

(White skip processing)
Next, the white skip process will be described. FIG. 2 is a diagram for explaining the white skip region.

  As shown in FIG. 2, the image 201 printed on the recording medium rarely fills up the entire recording medium 200. In this case, when the sub-scanning direction is viewed, a line that does not require printing may continue. At this time, a region in which these lines (also referred to as blank lines) continue is called white skip regions 202 and 203, and these white skip regions 202 and 203 are determined to be unnecessary to be printed.

  For example, in an ink jet type writing engine, since the transfer time can be shortened, control is performed such as printing by skipping the white skip areas 202 and 203. Thereby, printing performance (especially printing speed) can be improved.

(Background pattern synthesis)
Next, background pattern composition will be described. The copy process has a function called background pattern synthesis, which is a function of superimposing and printing a stamp image according to the application on the original original image. This stamp image is called a tint block image and is printed on the background of the original image.

  FIG. 3 is a diagram for explaining tint block synthesis. FIG. 3A shows a case where the ratio of the image 311 to be printed to the recording medium 301 is large. In the example shown in FIG. 3A, since the image 311 is approximately the same size as the copy-forgery-inhibited pattern image 312, there is almost no white skip region regardless of whether or not the copy-forgery-inhibited pattern image 312 is combined.

  FIG. 3B shows a case where the ratio of the image 321 to be printed to the recording medium 302 is small. In the example shown in FIG. 3B, since the image 321 to be printed is smaller than the copy-forgery-inhibited pattern image 322, the white skip area originally has a predetermined area. This is an example.

  Therefore, the effect of white skip processing may be reduced by combining the copy-forgery-inhibited pattern image. Each configuration of the image forming apparatus 100 in this embodiment for solving this inconvenience will be described below.

(Configuration of controller controller)
FIG. 4 is a block diagram illustrating an example of the configuration of the controller control unit 122. 4 includes a CPU I / F control unit 401, a memory controller 402, a bus arbiter 403, an input control unit 404, an image processing unit 405, an output control unit 406, an engine board I / F control unit 407, and a detection unit. 408.

  The CPU I / F control unit 401 controls the I / F with the controller CPU 121. The memory controller 402 controls I / F with the storage unit 123. The bus arbiter 403 determines where to give the right to use the bus in response to a bus use request from each component connected to the same bus.

  The input control unit 404 controls to store the image data acquired from the engine board I / F control unit 407 in the storage unit 123. The image processing unit 405 performs image processing corresponding to the application on the acquired image.

  The output control unit 406 outputs the image data stored in the storage unit 123 or the image data processed by the image processing unit 405 to the engine board 101 via the engine board I / F control unit 407.

  The engine board I / F control means 407 controls I / F with the engine board 101 and exchanges data.

  The detection means 408 acquires image data and detects a white skip area from the acquired image data. The detection unit 408 acquires image data by monitoring a transfer signal of a bus connected to the memory controller 402 when the image data is accumulated and read out from the storage unit 123 via the memory controller 402. Good.

  The detection unit 408 uses, for example, a monitor of a write transfer signal to the memory controller 402 for the image processing unit 405 to write image data into the storage unit 123. Accordingly, in order to detect the white skip area, the detection unit 408 can detect the white skip area without imposing a load due to data transfer on the bus arbiter 403 or the memory controller 402.

  The detection means 408 may use a known technique for detecting the white skip area. For example, the detection unit 408 detects a band in a region where there is no print image (see Patent Document 1).

  The detection unit 408 includes a calculation unit 409. The calculation unit 409 calculates the size of the print area in the sub-scanning direction of the recording medium using the white skip area detected from the image data. This size of the print area is called a sub-scan effective print size, and the size of the recording medium in the sub-scan direction is called a reference sub-scan size.

The calculating unit 409 calculates the sub-scanning effective print size using the following formula (1).
Sub-scan effective print size = reference sub-scan size−white skip area size (number of sub-scan lines) (1)
The calculating unit 409 calculates the reduction rate using the following formula.
Reduction ratio = sub-scanning effective print size / reference sub-scanning size (2)
The detection unit 408 accumulates the calculated reduction ratio and / or sub-scanning effective print size as scaling information in a register (not shown). The controller CPU 121 can freely read the scaling information from this register via the CPU I / F control means 401.

  Note that the calculation unit 409 is not necessarily included in the detection unit 408 and may be configured independently of the detection unit 408.

(Configuration of engine control unit)
FIG. 5 is a block diagram illustrating an example of the configuration of the engine control unit 113. The engine control unit 113 shown in FIG. 5 includes a CPU I / F control unit 501, a reading unit I / F control unit 502, a reading image processing unit 503, a controller board I / F control unit 504, a writing image processing unit 505, and a writing unit I. / F control means 506 is provided.

  CPU I / F control means 501 controls I / F with engine CPU 111. The reading unit I / F control unit 502 receives the image data acquired from the reading control unit 112 and outputs it to the read image processing unit 503.

  The read image processing unit 503 processes the image data acquired from the reading unit I / F control unit 502 and outputs the processed image data to the controller board I / F control unit 504.

  The controller board I / F control means 504 controls I / F with the controller board 102. For example, the controller board I / F control unit 504 controls to output the image data acquired from the read image processing unit 503 to the controller board 102, and outputs the image data acquired from the controller board 102 to the write image processing unit 505. Control to do.

  The writing image processing unit 505 performs image processing for writing on the image data acquired from the controller board I / F control unit 504. The writing image processing means 505 includes 1CH processing means 507 to 4CH processing means 508 and 5CH processing means 509.

  The 1CH processing unit 507 to the 4CH processing unit 508 divide and process an image for each color of CMYK. The 5CH processing unit 509 is also a combining unit that performs copy-forgery-inhibited pattern combination, and performs a copy-forgery-inhibited pattern image channel process. For example, the 5CH processing unit 509 scales the copy-forgery-inhibited pattern image in accordance with the size of the print area, and synthesizes the scaled copy-forgery-inhibited pattern image with the image data processed by the 1CH processing unit 507 to the 4CH processing unit 508. The processing means of each channel can perform processing in parallel. Details of the 5CH processing means 509 will be described later with reference to FIG.

  The writing unit I / F control unit 506 acquires the image data processed by the writing image processing unit 505 and outputs it to the writing unit 104.

(Configuration of 5CH processing means)
FIG. 6 is a block diagram illustrating an example of the configuration of the 5CH processing unit 509. The 5CH processing unit 509 shown in FIG. 6 includes an image expansion unit 601, a scaling unit 602, and a shift / cut / fill unit 603.

  The image decompression unit 601 performs decompression processing on the copy-forgery-inhibited pattern image acquired from the controller board I / F control unit 504 if compressed, and outputs the decompressed copy-forgery-inhibited pattern image to the scaling unit 602. Further, the image decompression unit 601 outputs the tint block image as it is to the scaling unit 602 when the tint block image is not compressed.

  The scaling unit 602 acquires the copy-forgery-inhibited pattern image output from the image expansion unit 601 and scales the copy-forgery-inhibited pattern image based on scaling information (for example, a reduction ratio). The scaling unit 602 outputs the scaled copy-forgery-inhibited pattern image to the shift / cut / fill unit 603.

  The scaling information is provided to the 5CH processing unit 509 using any of the methods described below.

(Method 1)
Through the communication between the controller CPU 121 and the engine CPU 111, the engine CPU 111 acquires the scaling information. The 5CH processing unit 509 is provided with scaling information from the engine CPU 111 by software control.

(Method 2)
A dedicated register is provided on the engine board 101 side, and magnification information is written from the controller CPU 121. The 5CH processing means 509 reads magnification information from a dedicated register.

(Method 3)
The scaling information is attached to the copy-forgery-inhibited pattern image on the controller board 102 side and transmitted to the engine board 101 side. The 5CH processing unit 509 acquires scaling information attached to the copy-forgery-inhibited pattern image.

  The shift / cut / fill unit 603 performs processing such as image shift, image cut, and fill (white-filling) for adjusting the printing position and the like in accordance with the recording medium. The shift / cut / fill unit 603 outputs the processed image data to the writing unit I / F control unit 506.

<Print result>
Next, the printing result after performing the tint block composition process according to the embodiment will be described. FIG. 7 is a diagram illustrating an example of the print result (part 1). As shown in FIG. 7, the scaling unit 602 scales the copy-forgery-inhibited pattern image 702 in accordance with the size of the printed image 701 in the sub-scanning direction. The 5CH processing unit 509 combines the scaled copy-forgery-inhibited pattern image 702 with the printed image 701.

  As a result, the white skip area is maintained in the print result output by the writing unit 104 as shown in FIG. Therefore, the image forming apparatus 100 can effectively perform white skip processing.

  Since the sub-scanning direction is used as a reference, the original tint block image is smaller than the main scanning direction. Therefore, it is possible to prevent the copy-forgery-inhibited pattern image from being determined by repeatedly combining the reduced copy-forgery-inhibited pattern image in the main scanning direction.

  FIG. 8 is a diagram for explaining repetition of a tint block image. As shown in FIG. 8, the copy-forgery-inhibited pattern image 802 may be repeatedly combined in the main scanning direction.

At this time, the scaling unit 602 calculates the number of repetitions according to the following equations (3) and (4).
Main scanning effective print size = reference main scanning size × reduction ratio (3)
Number of repetitions = reference main scan size / main scan effective print size (4)
Here, when the main scanning effective print size of Expression (3) is substituted into Expression (4), the following Expression (5) is established.
Number of repetitions = 1 / reduction ratio (5)
With respect to the reference main scanning size, the number of repetitions, which is the size of the reference recording medium in the main scanning direction, is rounded up to an integer. Note that the number of repetitions may be calculated by the calculation unit 409, and the number of repetitions may be included in the scaling information. In the example illustrated in FIG. 8, an example in which the number of repetitions is calculated as three is shown.

  FIG. 9 is a diagram illustrating an example of the printing result (part 2). The example shown in FIG. 9 shows the printing result when the copy-forgery-inhibited pattern image is printed with the number of repetitions shown in FIG. The 5CH processing unit 509 repeatedly synthesizes the scaled copy-forgery-inhibited pattern image in the main scanning direction by the number of repetitions calculated based on the reciprocal of the reduction ratio into image data. As shown in FIG. 9, by repeatedly combining the copy-forgery-inhibited pattern image in the main scanning direction a plurality of times, it becomes possible to distinguish the copy-forgery-inhibited pattern image and maintain the effect of the copy-forgery-inhibited pattern image.

  In addition, the scaling unit 602 may determine a lower limit value that is a minimum size for the copy-forgery-inhibited pattern image in advance. The scaling unit 602 scales the copy-forgery-inhibited pattern image using the lower limit value when the reduction ratio is smaller than the lower limit value. As a result, even when the print area of the original image is very small, or when the copy-forgery-inhibited pattern image is combined with a blank page, it is possible to perform printing in a size that allows the meaning of the copy-forgery-inhibited pattern image to be read.

  In addition, the above-described tint block synthesis process is configured to reduce the tint block image for one surface in accordance with the print area in the sub-scanning direction. However, the storage unit 123 may hold a minimum size for which the meaning of the copy-forgery-inhibited pattern image is known, and the scaling unit 602 may enlarge the reduced copy-forgery-inhibited pattern image. For example, the scaling unit 602 may enlarge the reduced copy-forgery-inhibited pattern image according to the size of the print area. As a result, the amount of data transferred from the controller board 102 to the engine board 101 can be reduced, and the load on the I / F can be reduced.

  In addition, the image forming apparatus 100 can perform the white skip processing when the document title and the page printing are excluded by performing the above-described processing on the image excluding the header and footer portions.

<Operation>
Next, the operation of the image forming apparatus 100 in the embodiment will be described. FIG. 10 is a flowchart illustrating an example of processing of the controller control unit 122.

  In step S 101, the input control unit 404 acquires the image data transmitted from the engine board 101 via the engine board I / F control unit 407. The input control unit 404 controls to write the acquired image data in the storage unit 123.

  In step S <b> 102, the image processing unit 405 reads image data from the storage unit 123.

  In step S103, the image processing unit 405 performs predetermined image processing on the image data. The predetermined image processing is, for example, aggregation processing.

  In step S <b> 104, the image processing unit 405 writes the image data after the image processing in the storage unit 123.

  In step S <b> 105, the detection unit 408 acquires image data by monitoring write data on the bus when the image processing unit 405 writes image data into the storage unit 123. The detecting means 408 detects a white skip area from this image data.

  In step S <b> 106, the output control unit 406 controls the image data and the tint block image after image processing to be read from the storage unit 123 and output to the engine board 101.

  Note that the monitoring by the detection unit 408 is not necessarily limited to the data transfer after step S104. Eventually, the detection unit 408 may perform monitoring at the time of data transfer to the storage unit 123 after the output image to be printed is determined.

  For example, if the size of the image printed by image processing does not change, monitoring may be performed at the time of data transfer after step S101. Note that when there is an aggregation process of a plurality of pages in the image processing means 405, the area of the image to be printed on the recording medium to be printed changes, so the monitoring timing shown in FIG. 10 is suitable. That is, the detection unit 408 monitors the bus transfer signal in the data transfer to the memory generally performed by a functional module related to normal copy processing. A functional module refers to each means when mounted as a module, for example.

  FIG. 11 is a flowchart illustrating an example of processing of the engine control unit 113. In step S <b> 201 shown in FIG. 11, the write image processing unit 505 acquires image data and a tint block image from the controller board 101 via the controller board I / F control unit 504.

  In step S <b> 202, the writing image processing unit 505 processes the acquired image data by dividing the channel for each color and performs a tint block synthesis process. The tint block composition process will be described later with reference to FIG.

  In step S 203, the writing unit I / F control unit 506 outputs the image data combined with the background pattern by the writing image processing unit 505 to the writing unit 104.

  FIG. 12 is a flowchart illustrating an example of a tint block composition process. In step S301 shown in FIG. 12, if the acquired copy-forgery-inhibited pattern image is compressed, the image expansion unit 601 performs expansion processing on the compressed copy-forgery-inhibited pattern image.

  In step S302, the scaling unit 602 scales the copy-forgery-inhibited pattern image based on the scaling information. The scaling unit 602 reduces the copy-forgery-inhibited pattern image, for example, by applying a reduction ratio. Further, when acquiring the reduced copy-forgery-inhibited pattern image, the scaling unit 602 enlarges the reduced copy-forgery-inhibited pattern image in accordance with the print area. As a result, the size of the print area in the sub-scanning direction and the size of the tint block image in the sub-scanning direction become approximately the same.

  In step S303, the 5CH processing unit 509 adjusts the print position and the like by the shift / cut / fill unit 603, and performs a process of combining the scaled copy-forgery-inhibited pattern image with the image data.

  Thus, the white skip area can be secured by scaling the copy-forgery-inhibited pattern image in accordance with the size of the print area and synthesizing the scaled pattern image after scaling.

  As described above, according to the embodiment, the white skip process can be effectively performed even when the copy-forgery-inhibited pattern image is printed.

[Modification]
Next, an information processing apparatus according to a modification will be described. A program executed by the information processing apparatus according to the embodiment is an installable or executable file and is read by a computer such as a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile Disk). Recorded on a possible recording medium and provided.

  Further, the program executed by the information processing apparatus of the embodiment may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network.

  Further, the program executed by the information processing apparatus of the embodiment may be configured to be provided by being incorporated in advance in a ROM or the like.

  The program executed by the information processing apparatus according to the embodiment has a module configuration including the above-described units. As actual hardware, the CPU 101 (processor) reads the program from the recording medium and executes the program. Each function is loaded on the main memory, and each function is created on the main memory.

  In addition, this invention is not limited to the said Example as it is, A component can be deform | transformed and embodied in the range which does not deviate from the summary in an implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiments.

DESCRIPTION OF SYMBOLS 100 Image forming apparatus 101 Engine board 102 Controller board 103 Reading unit 104 Writing unit 111 Engine CPU
112 Reading control unit 113 Engine control unit 114 Writing control unit 121 Controller CPU
122 controller control unit 123 storage unit 402 memory controller 404 input control unit 405 image processing unit 406 output control unit 408 detection unit 409 calculation unit 503 read image processing unit 505 write image processing unit 509 5CH processing unit 601 image expansion unit 602 scaling unit 603 Shift, cut and fill means

JP 2010-23461 A

Claims (6)

Detecting means for acquiring image data and detecting an area where there is no image to be printed in the sub-scanning direction;
Calculation means for calculating the size of the print area in the sub-scanning direction based on the area detected by the detection means;
According to the size of the print area calculated by the calculation means, the scale pattern image to be printed superimposed on the image is scaled, and the composition means for synthesizing the scale pattern image after scaling to the image data;
An image forming apparatus comprising: The calculating means includes
Calculate the reduction ratio of the size of the print area with respect to the size of the recording medium as a reference in the sub-scanning direction,
The synthesis means includes
The image forming apparatus according to claim 1, wherein the copy-forgery-inhibited pattern image is scaled according to the reduction ratio. The calculating means includes
Calculating the number of repetitions of the copy-forgery-inhibited pattern image in the main scanning direction based on the reciprocal of the reduction ratio;
The synthesis means includes
The image forming apparatus according to claim 2, wherein the copy-forgery-inhibited pattern image after scaling is repeated in the main scanning direction for the number of repetitions. The scaling means is
The image forming apparatus according to claim 2, wherein a lower limit value is provided for the reduction ratio, and if the reduction ratio is smaller than the lower limit value, scaling is performed using the lower limit value. Storage means for storing a pre-reduced copy-forgery-inhibited pattern image;
The synthesis means includes
The image forming apparatus according to claim 1, wherein the reduced copy-forgery-inhibited pattern image transferred from the storage unit is enlarged according to a size of the print area. The detection means includes
The image processing apparatus according to claim 1, wherein the image data is acquired by monitoring a data transfer signal on a bus through which the image data is transferred to a storage unit.

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