JP2006108828A - Image processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor capable of processing a plurality of jobs at the same time at a high speed even when image data of processing objects exist in the same memory in a configuration including a plurality of compression expansion units and each having an exclusive use memory. <P>SOLUTION: When image data to be processed in a second job are stored in a buffer memory 21 of the compression expansion unit 23 in use by a first job, a DMA controller 40 transfers the image data to a buffer memory 31 of the other compression expansion unit 33 not in use, and the compression expansion unit 33 of the buffer memory 31 is used to perform the second job. The contention of the compression expansion units is avoided and a free compression expansion unit can efficiently be utilized. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image processing apparatus such as a multifunction peripheral having a scanner function for reading a document, a copy function for copying a document, and a printer function for printing based on print data. In particular, the present invention executes a plurality of jobs simultaneously. The present invention relates to a possible image processing apparatus.

  In an image processing apparatus such as a multifunction peripheral, a plurality of jobs are executed simultaneously within a range in which input / output devices do not compete with each other in order to reduce user waiting time and increase convenience. For example, it is possible to execute a document reading operation related to the next copy job while executing an output operation related to a plurality of copy jobs, or to execute a print job while executing a scanner job. .

  In addition, when image data is compressed and handled in the device in response to a request for memory capacity reduction, multiple compression processing units are provided so that simultaneous execution of multiple jobs is not hindered due to a lack of compression processing units. An image processing apparatus provided has been proposed (see, for example, Patent Document 1).

  Furthermore, the present applicant pays attention to the fact that frequent access to the same memory by a plurality of compression / decompression units causes a reduction in processing speed, and a dedicated buffer memory is provided for each compression / decompression unit to access the memory. Japanese Patent Application No. 2003-399765 has proposed an image processing apparatus in which the image data is dispersed.

JP 2003-23543 A

  When the image data handled by each job is separate and independent, such as when a scanner job and a copy job are executed simultaneously, the image data of each job can be obtained by using the above technique proposed by the applicant. Can be stored in different buffer memories and processed smoothly by the compression / decompression unit corresponding to each buffer memory.

  However, if a job for displaying thumbnail images of each page related to the print job is executed simultaneously during execution of the print job, the image data to be processed is the same for these two jobs, and the thumbnail job Image data to be processed is stored in a buffer memory for print jobs. For this reason, even when other compression / decompression units for the buffer memory are not in use, a thumbnail job cannot be executed using this free compression / decompression unit, and one compression / decompression unit can be divided into two jobs. You had to share it at the expense of processing speed or abort the thumbnail job.

  Even if the image data to be processed is not the same, if the image data to be processed by each job to be executed simultaneously is stored in the same buffer memory, the compression / decompression unit competes and Similar problems arise.

  The present invention is intended to solve the above-described problem. In a configuration having a plurality of compression / decompression units and dedicated memories, a plurality of jobs can be processed even when image data to be processed exists in the same memory. An object of the present invention is to provide an image processing apparatus capable of processing simultaneously and at high speed.

The invention according to claim 1 is an image processing apparatus capable of simultaneously executing a plurality of jobs.
A plurality of compression / decompression units for compressing / decompressing image data;
A memory provided for each compression / decompression unit;
Transfer means for transferring image data between the memories;
Control means for controlling the execution of the job,
When the image data to be processed in the second job is stored in the memory corresponding to the compression / expansion unit being used in the first job, the control unit compresses the image data that is not in use. Is transferred to the memory corresponding to the above-mentioned transfer means, and the second job is executed using the compression / decompression unit of the memory.

  According to the above invention, when image data to be processed by the second job is stored in the memory corresponding to the compression / decompression unit being used by the first job, the image data is compressed / expanded that is not in use. The data is transferred to the memory corresponding to the copy by the transfer means, and the second job is executed using the compression / decompression unit of the memory. The transfer by the transfer means may be a transfer by a CPU (Central Processing Unit) in addition to a DMA (Direct Memory Access) transfer. The image data to be processed by the second job may be the same as the image data to be processed by the first job as long as it is stored in the memory of the compression / decompression unit in use by the first job. It may be different.

The invention according to claim 2 is the image processing apparatus according to claim 1, wherein the transfer means is direct memory access control means.

  According to the above invention, image data is transferred by DMA (direct memory access) transfer. Since the DMA control means serves as a bus master and transfers data, image data is transferred without imposing a burden on the CPU that performs job execution control and the like.

The invention according to claim 3 is the image processing apparatus according to claim 1, wherein the control means performs the transfer only when a predetermined transfer condition is satisfied.

  According to the above invention, transfer is executed only when a predetermined transfer condition is satisfied. For example, (1) image data to be processed in the job is stored in a memory corresponding to any compression / decompression unit, and (2) compression / decompression corresponding to a memory in which image data to be processed is stored. Transfer is performed when a condition is satisfied, such as that the copy is being used by another job, or (3) that there is a compression / decompression portion that is not in use. If there is no compression / decompression unit that is not in use, for example, the execution of the job is postponed or stopped.

  In addition, priorities and other distinctions may be given to a plurality of memories, and image data may not be transferred when a transfer source or transfer destination memory is a specific memory. For example, it may be regulated not to transfer from a low-priority memory used for general jobs to a high-priority memory for print jobs.

  Further, when the compression / decompression unit currently used in the first job becomes empty is checked, and the time required until it becomes empty is less than a certain time, the transfer condition is not satisfied, and the compression / decompression unit It may be configured to wait for execution of the second job until the space becomes empty, and execute the second job by the compression / decompression unit.

The invention according to claim 4 is characterized in that the control means selects a transfer destination memory according to a predetermined selection condition when there are a plurality of compression / decompression units that are not in use. It is.

  According to the above invention, when there are a plurality of transfer destination candidates, an appropriate transfer destination is selected. For example, the transfer destination can be selected according to the priority given to each memory.

  According to the image processing apparatus of the present invention, when image data to be processed by the second job is stored in the memory corresponding to the compression / decompression unit being used by the first job, the image data is Since the second job is executed by using the compression / decompression unit of the memory and transferred to the memory corresponding to the compression / decompression unit that is not in use, a plurality of jobs can be processed even when the image data to be processed exists in the same memory. Can be processed simultaneously and at high speed.

  When image data is transferred by DMA transfer, almost no CPU resources are used for the transfer, so that the image data can be transferred without affecting the execution of the first job and other controls.

  When the above transfer is performed only when a predetermined transfer condition is satisfied, when there is no compression / expansion unit that is not in use, or when a predetermined transfer condition is not met even when there is a compression / expansion unit that is not in use Can be controlled not to execute the transfer.

  When there are a plurality of compression / decompression units that are not in use and the transfer destination memory is selected according to a predetermined selection condition, the image data to be processed can be transferred from the plurality of candidates to the optimum memory.

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

  FIG. 1 is a block diagram showing a schematic configuration of an image processing apparatus 10 according to an embodiment of the present invention. The image processing apparatus 10 includes a scanner function for reading a document image, a copy function for creating a copy of the read image on recording paper, a printer function for creating and outputting an image corresponding to print data received from an external device on the recording paper, It is configured as a so-called digital multifunction peripheral having a plurality of functions such as an image transmission function for transmitting / receiving image data to / from an external device via a network.

  The image processing apparatus 10 includes a scanner unit 11, a printer unit 12, and various devices connected to a PCI (Peripheral Components Interconnect) bus 13. The scanner unit 11 is an input unit that reads a document image, and moves a light source that irradiates the document, a line image sensor that reads the document by one line in the width direction thereof, and a reading position in units of lines in the length direction of the document. The moving means and an optical path composed of a lens and a mirror for guiding the reflected light from the original to the line image sensor to form an image. The line image sensor is composed of a CCD (Charge Coupled Device). The analog image signal output from the line image sensor is A / D converted and captured as digital image data.

  The printer unit 12 functions to form and output an image corresponding to the image data on a recording sheet by an electrophotographic process. The printer unit 12 is configured as a so-called laser printer having a recording paper transport device, a photosensitive drum, a charging device, a laser unit, a developing device, a transfer separation device, a cleaning device, and a fixing device. ing.

  A first image processing unit 20 and a second image processing unit 30 are connected to the PCI bus 13. The first image processing unit 20 includes a first buffer memory 21, a first memory control unit 22, and a first compression / decompression unit 23. The first buffer memory 21 is a RAM (Random Access Memory) constituted by a semiconductor memory, and has a memory capacity capable of storing about 100 planes of image data as a standard image. The first memory control unit 22 is a circuit that controls reading and writing of image data to the first buffer memory 21. The first compression / decompression unit 23 performs a function of compressing and decompressing image data transferred via the first memory control unit 22. The first buffer memory 21 and the first compression / decompression unit 23 are each connected to a first memory control unit 22, and the first memory control unit 22 is connected to the PCI bus 13.

  The second image processing unit 30 has the same configuration as the first image processing unit 20, and includes a second buffer memory 31, a second memory control unit 32, and a second compression / decompression unit 33. Yes. The scanner unit 11 is connected to the first memory control unit 22 of the first image processing unit 20 and the second memory control unit 32 of the second image processing unit 30, and the image data is transferred to the first image processing unit 20. And the second image processing unit 30. The printer unit 12 is connected to the first memory control unit 22 of the first image processing unit 20, and can output image data only through the first image processing unit 20.

  The DMA controller 40 as transfer means transfers image data as a bus master between the first buffer memory 21 of the first image processing unit 20 and the second buffer memory 31 of the second image processing unit 30. Fulfills the function of

  Further, the image processing apparatus 10 includes a control unit 14 that performs overall control of the operation of the apparatus. The control unit 14 includes a circuit having a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM as main parts. The control unit 14 is connected to a CPU bus 15 different from the PCI bus 13 for flowing image data, and the CPU bus 15 and the PCI bus 13 are connected via a PCI bridge 16. The control unit 14 controls the execution of a job and the flow of image data at the time of job execution, and also functions as a control unit that instructs the DMA controller 40 to transfer data.

  In addition, a USB (Universal Serial Bus) interface unit 41, PCI bridges 42 and 44, an IDE (Integrated Drive Electronics) interface unit 46, and a network control unit 48 are connected to the PCI bus 13. . The USB interface unit 41 is an input / output circuit for connecting various USB devices. The PCI bridges 42 and 44 are interface circuits for connecting the PCI bus and other types of buses. The PCI bridge 42 is connected to a print controller 43 that analyzes print data and develops it into raster image data. The print controller unit 43 supports various page script languages in addition to text data.

  An operation panel 45 is connected to the PCI bridge 44. The operation panel 45 includes a liquid crystal display having a touch panel on the surface and various operation switches, and has a function of performing various guidance displays and status displays for the user and receiving various operations from the user. On the operation panel 45, thumbnail images obtained by simplifying and downsizing the document image are also displayed.

  A hard disk device 47 is connected to the IDE interface unit 46. The IDE interface unit 46 is an interface circuit for connecting the hard disk device 47 to the PCI bus 13 or the like. The hard disk device 47 stores compressed image data. The network control unit 48 performs a function of communicating with various external devices via a network 49 such as a LAN (local area network).

  The image processing apparatus 10 can execute a plurality of jobs simultaneously as long as the input / output device and other devices do not compete. In particular, by having the first image processing unit 20 and the second image processing unit 30, two jobs involving compression and / or expansion can be executed simultaneously. A job that uses the printer unit 12 preferentially uses the first image processing unit 20 to which the printer unit 12 is connected.

  FIG. 2 shows the flow of image data when a copy job and a print data reception job are executed simultaneously. First, the copy job will be described. The image data obtained by reading the document with the scanner unit 11 is compressed by the first compression / decompression unit 23 via the first memory control unit 22 of the first image processing unit 20 and then the first buffer memory. 21 (path C1). Thereafter, the image data is decompressed by the first compression / decompression unit 23 via the first memory control unit 22 of the first image processing unit 20 and output to the printer unit 12 to form an image (pass C2). In the case of multiple copy, the compressed image data stored in the first buffer memory 21 is repeatedly printed through the above-described pass C2.

  In the print data reception job, image data obtained by rasterizing the received print data by the print controller unit 43 is sent to the second memory control unit 32 of the second image processing unit 30 via the PCI bus 13 and the second memory control unit 32. It is stored in the buffer memory 31 (path P1). The image data is compressed by the second compression / decompression unit 33, returned to the second buffer memory 31 (path P2), and further transferred to the hard disk device 47 (path P3).

  As shown in FIG. 3, the image data thus stored in the hard disk device 47 is transferred from the hard disk device 47 via the first memory control unit 22 of the first image processing unit 20 after the output processing of the copy job is completed. The data is read out to the first buffer memory 21 (pass P4), further decompressed by the first compression / decompression unit 23, and output to the printer unit 12 (pass P5).

  Since the image data to be processed is different between the copy job and the print data reception job, each image data is compressed and decompressed independently and simultaneously using the first image processing unit 20 and the second image processing unit 30. can do. However, when displaying thumbnails of images related to a job during the execution of a copy job, image data to be processed by the thumbnail job and image data to be processed by the job being executed (current job) are displayed. If they are the same, the compression / decompression unit competes as it is.

  Therefore, the image processing apparatus 10 according to the present embodiment DMA-transfers image data to be processed by the thumbnail job from the buffer memory of the image processing unit being used by the current job to the buffer memory of the other image processing unit. A copy is created, and a thumbnail job is executed using the copy destination image processing unit.

  FIG. 4 shows the flow of image data when thumbnails of images related to this job are displayed during execution of the copy job. The flow of image data related to the copy job is the same as that shown in FIG. Since the image data to be processed by the thumbnail job is stored in the first buffer memory 21 of the first image processing unit 20 in use by the current job (copy job), first, the image data to be processed is DMA-transferred. The controller 40 transfers the data from the first buffer memory 21 to the second buffer memory 31 of the second image processing unit 30 (path S1). Thereafter, the image data is decompressed by the second compression / decompression unit 33 (pass S2), and a thumbnail image obtained by reducing the decompressed image is transferred to the operation panel 45 and displayed (pass S3).

  The transfer of the path S1 by the DMA controller 40 is performed during the idle time of the operation related to the copy job. For example, it is performed during the blanking period between pages and every line. For this reason, the transfer described above does not hinder the flow of image data related to the copy job or reduce the processing speed. Further, the data transfer by the DMA controller 40 is performed by the DMA controller 40 itself as a bus master, so that the processing load is hardly applied to the CPU of the control unit 14. Therefore, this transfer hardly affects the copy job and other processes, and the copy job and other processes ensure normal performance.

  FIG. 5 shows the flow of image data when displaying thumbnails of images related to the job during execution of the scan to E-Mail job. The scan to E-mail job is a job for sending an image read by the scanner unit 11 as an attached file by e-mail.

  The scan to E-Mail job is executed using the second image processing unit 30 because the printer unit 12 is not used. The image data obtained by reading the document with the scanner unit 11 is compressed by the second compression / decompression unit 33 via the second memory control unit 32 of the second image processing unit 30, and then the second buffer memory. 31 (path E1). After that, the image data is decompressed by the second compression / decompression unit 33 via the second memory control unit 32 of the second image processing unit 30, converted in resolution, converted into a file, attached to an e-mail, and sent to a designated destination. Is transmitted (path E2).

  Since the image data to be processed by the thumbnail job is stored in the second buffer memory 31 of the second image processing unit 30 in use by the current job (scan to E-Mail job), first, the image to be processed Data is transferred from the second buffer memory 31 to the first buffer memory 21 of the first image processing unit 20 by the DMA controller 40 (pass S11). Thereafter, the thumbnail image is decompressed by the first compression / decompression unit 23 (pass S12), and the thumbnail image processed by reducing the decompressed image is transferred to the operation panel 45 and displayed (pass S13).

  In this case as well, the data transfer by the DMA controller 40 hardly affects the execution of the scan to E-Mail job and other processes, and the copy job and other processes ensure normal performance.

  FIG. 6 shows the flow of processing when displaying a thumbnail image of the current job. It is checked whether the current job (currently executed job) is using the first image processing unit 20 (main) or the second image processing unit 30 (sub) (step S101). If the current job is using the first image processing unit 20 (main) (step S101; main), the image data to be processed by the thumbnail job is transferred from the first buffer memory 21 using the DMA controller 40. DMA transfer to the second buffer memory 31 (step S102), and the image data transferred to the second buffer memory 31 is decompressed using the second compression / decompression unit 33 (step S103). On the other hand, if the current job is using the second image processing unit 30 (sub) (step S101; sub), the image data to be processed by the thumbnail job is transferred to the second buffer memory 31 using the DMA controller 40. To the first buffer memory 21 (step S104), and the image data transferred to the first buffer memory 21 is decompressed using the first compression / decompression unit 23 (step S105).

  Thereafter, the thumbnail image is processed by reducing the decompressed image data to create a thumbnail image (step S106), the thumbnail image is transferred to the operation panel 45 and displayed (step S107), and the process ends (END).

  In the above example, the flow in the case of specializing in displaying the thumbnail image of the current job is shown. Next, the flow of processing related to data transfer in the case of generalization will be described based on FIG. Here, it is assumed that there are two or more arbitrary image processing units.

  First, it is determined whether or not image data to be processed by the job exists in the buffer memory of any image processing unit (step S201). The location other than the buffer memory is, for example, the hard disk device 47. When the image data to be processed exists in the buffer memory of any image processing unit (step S201; Y), it is determined whether another job is using the compression / decompression unit of the image processing unit ( Step S202).

  When the compression / decompression unit of the image processing unit in which the image data to be processed exists is in use (step S202; Y), it is checked whether there is a compression / decompression unit that is not in use (step S203). If the compression / decompression unit of all the image processing units is in use (step S203; N), the process is stopped due to an error (step S208) and the process ends (END).

  When there is a compression / decompression unit that is not in use (step S203; Y), one of them is selected (step S204), and the processing target is stored in the buffer memory of the image processing unit to which the selected compression / decompression unit belongs. The image data is transferred (step S205). Thereafter, the image data is decompressed using the compression / decompression unit of the destination image processing unit (step S206), output to the output destination corresponding to the job (step S207), and the processing is terminated (end). For example, a print job is printed, and a thumbnail job is reduced and displayed on the operation panel 45.

  If the compression / decompression unit of the image processing unit in which the image data to be processed exists is not in use (step S202; N), decompression is performed using the compression / decompression unit (step S206) and output (step S207, end) ).

  When the image data to be processed by the job does not exist in the buffer memory of the image processing unit, for example, in the hard disk device 47 (step S201; N), whether or not there is a compression / decompression unit that is not in use. If the compression / decompression unit of all image processing units is in use (step S203; N), the process is stopped due to an error (step S208) and the process ends (END).

  When there is a compression / decompression unit that is not in use (step S203; Y), one of them is selected (step S204), and the processing target is stored in the buffer memory of the image processing unit to which the selected compression / decompression unit belongs. The image data is transferred (step S205). Thereafter, the image data is decompressed using the compression / decompression unit of the destination image processing unit (step S206), output to the output destination corresponding to the job (step S207), and the processing is terminated (end).

  When there are a plurality of transfer destination candidates, a selection method for selecting an appropriate transfer destination from among them may be set as appropriate. For example, the selection can be made based on the free capacity of the transfer destination buffer memory, the priority given to the transfer destination buffer memory, the priority of the job, the status of the job waiting to be executed, and the like. If the next job waiting for execution uses a specific buffer memory as in the case of a print job, the buffer memory may be excluded from the transfer destination candidates.

  The embodiment of the present invention has been described with reference to the drawings. However, the specific configuration is not limited to that shown in the embodiment, and there are changes and additions within the scope of the present invention. Are also included in the present invention.

  For example, in the embodiment, two sets of image processing units are provided, but three or more sets may be provided. In the embodiment, the image data is transferred using the DMA controller 40, but may be transferred using the CPU of the control unit 14. Even in this case, if the CPU has sufficient processing capacity, the performance of the image processing apparatus 10 does not deteriorate.

  In the embodiment, when there is a compression / decompression unit that is not in use, the image data is transferred to the buffer memory corresponding to the compression / decompression unit for processing. It may be determined based on the weighting condition. For example, each buffer memory may be prioritized, and transfer from a lower priority to a higher priority may be prohibited. That is, if the buffer memory of the image processing unit connected to the printer is set to a high priority, the image processing unit for print output can be easily maintained in an empty state, and it is possible to respond immediately to a print request. .

  Also, check when the job using the image processing unit corresponding to the buffer memory in which the image data to be processed is vacant, and if the time required until vacant is less than a certain time The job execution may be waited until the transfer condition is not satisfied and the compression / decompression unit becomes empty. Rather than transferring a large amount of image data, waiting for the end of a job in use is suitable when the job can be executed promptly.

  In addition, in the embodiment, the printer unit 12 is fixedly connected to the first image processing unit 20. However, as in the scanner unit 11, the printer unit 12 is switched to either the first image processing unit 20 or the second image processing unit 30. You may connect as possible. Further, the multifunction apparatus has been described as an example, but the type is not limited as long as it is an image processing apparatus including a plurality of image processing units.

It is a block diagram which shows the structure of the image processing apparatus concerning embodiment of this invention. FIG. 10 is an explanatory diagram illustrating an example of the flow of image data when the image processing apparatus according to the embodiment of the present invention simultaneously performs a print data reception operation during execution of a copy job. FIG. 3 is an explanatory diagram illustrating an example of a flow of image data when image data stored in a hard disk device is read and printed in the print data reception operation of FIG. 2. FIG. 10 is an explanatory diagram illustrating an example of the flow of image data when performing thumbnail display of an image related to a job during execution of a copy job. FIG. 10 is an explanatory diagram illustrating an example of a flow of image data when displaying thumbnails of images related to a job during execution of a scan to E-Mail job. 12 is a flowchart illustrating processing for displaying a thumbnail image of a current job. It is a flowchart which shows the generalized job execution process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Image processing apparatus 11 ... Scanner part 12 ... Printer part 13 ... PCI bus 14 ... Control part 20 ... 1st image processing part 21 ... 1st buffer memory 22 ... 1st memory control part 23 ... 1st compression / decompression Unit 30 ... Second image processing unit 31 ... Second buffer memory 32 ... Second memory control unit 33 ... Second compression / decompression unit 40 ... DMA controller 41 ... USB interface unit 42, 44 ... PCI bridge 43 ... Print controller Unit 45 ... operation panel 46 ... IDE interface unit 47 ... hard disk device 48 ... network control unit 49 ... network

Claims (4)

In an image processing apparatus that can execute multiple jobs simultaneously,
A plurality of compression / decompression units for compressing / decompressing image data;
A memory provided for each compression / decompression unit;
Transfer means for transferring image data between the memories;
Control means for controlling the execution of the job,
When the image data to be processed in the second job is stored in the memory corresponding to the compression / expansion unit being used in the first job, the control unit compresses the image data that is not in use. An image processing apparatus, wherein the image data is transferred to a memory corresponding to the image data by the transfer means, and the second job is executed using a compression / decompression unit of the memory. The image processing apparatus according to claim 1, wherein the transfer unit is a direct memory access control unit. The image processing apparatus according to claim 1, wherein the control unit performs the transfer only when a predetermined transfer condition is satisfied. The image processing apparatus according to claim 1, wherein the control unit selects a transfer destination memory according to a predetermined selection condition when there are a plurality of compression / decompression units that are not in use.

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