JPH11331528A - Image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the productivity of image output by improving the efficiency of access to a storage means (secondary storage device) as one of resources composing of an image processor for parallelly processing plural jobs. SOLUTION: This image processor stores inputted image data in a second storage means (secondary storage device) 4. In this case, when plural access requests to the second storage means 4 compete, based on at least one of whether that access request is a write request or read request and the kind of job generating that access request, concerning the plural access requests, the order of processing is determined.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image processing apparatus that performs processing (output processing and the like) on image data and includes storage means for storing and storing the image data.

[0002]

2. Description of the Related Art Conventionally, image processing apparatuses include, for example, a copy function, a print function, and a facsimile (FAX).
Like a so-called multifunction device having functions, it can handle a plurality of types of jobs (copy job, print job, FAX job, etc.) and has a function (multi-function function) of processing these jobs simultaneously and in parallel. What they have is widely known. In such an image processing apparatus, by executing various jobs (image processing) in parallel, resources constituting the apparatus are effectively used, and each job is completed in a short time. (See JP-A-5-336385).

Further, in an image processing apparatus having a multi-function function, when a request for using a certain resource conflicts among a plurality of jobs, a storage means (secondary storage device) such as a magnetic disk device or an optical disk device is used. Device). Then, by storing and accumulating the image data in the secondary storage device, even if the use requests of certain resources conflict, these use requests can be processed in order,
In addition, it is possible to output a plurality of copies by reading (inputting) image data at one time, or to output after editing image data for a plurality of pages.

Incidentally, the secondary storage device usually has an external access request (write request or read request).
Is written or read in accordance with the formula (1), but other writing or reading cannot be performed during writing or reading. That is,
Until a certain writing or reading is completed, the processing by the next access request cannot be performed. Moreover,
The time required for writing or reading is longer than that of a semiconductor memory or the like, and varies greatly depending on the size of image data and its storage location (storage location on a disk in a secondary storage device, etc.). I will.

On the other hand, a printer unit (image output unit) for outputting image data on a recording sheet is one of the resources constituting the image processing apparatus. The sheet is fed at regular intervals based on a predetermined reference signal (hereinafter, this reference signal is referred to as a pitch). For example, in the case of an image output unit that realizes a copy function of 30 CPM (Copy per Minute), a pitch signal is output every two seconds, so that one recording sheet is fed every two seconds.

Therefore, when the image data read from the secondary storage device is output by the image output unit, the image data may be output to a position where the image can be output due to, for example, contention of an access request to the secondary storage device as shown in FIG. If the reading of the image data is not completed before the recording paper arrives, it is necessary to perform a control for temporarily stopping the feeding of the recording paper (hereinafter, referred to as pitch skip control), and as a result, the image processing efficiency ( Image output).

In order to prevent such pitch skip control from occurring, for example, Japanese Patent Laid-Open Publication No. Hei 5-292265 discloses this secondary storage device based on the size (compression size) of image data and the processing capability of the secondary storage device. There has been disclosed an image processing apparatus in which the time required for reading image data from a computer is predicted, thereby enabling scheduling for reading.

[0008] For example, Japanese Unexamined Patent Publication No. 7-200386 discloses an access request to a secondary storage device.
By automatically setting the priority of an access request from a resource having a high frequency of occurrence to a high level, and processing a high-priority access request and a low-priority access request at an appropriate ratio, the secondary storage device It is disclosed that the efficiency of access to the URL can be improved.

[0009]

However, in the above-described conventional image processing apparatus, there is a possibility that the following problems may occur.

For example, in the image processing apparatus disclosed in Japanese Patent Application Laid-Open No. 5-292265, it is necessary to perform a calculation using the worst value for predicting the read time and give a certain margin to the calculation result. Actually, there is a possibility that a time zone in which the secondary storage device is not executing writing or reading may occur. That is, although the occurrence of the pitch skip control can be suppressed, the efficiency of access to the secondary storage device is wasted, and as a result, the productivity of the image processing apparatus is hindered. Furthermore, since it is necessary to predict the read time and perform the read scheduling, the software control becomes complicated. In addition, when the performance of the secondary storage device becomes different due to the replacement of the secondary storage device or the like, it is necessary to change parameters and the like for calculating the predicted time.

In the apparatus disclosed in, for example, Japanese Patent Application Laid-Open No. 7-200386, the priority of an access request having a high frequency of occurrence is set high. That is,
For example, if the frequency of access requests from the image input unit that inputs image data is high, the write request from the image input unit to the secondary storage device has priority. Therefore, in this case, the occurrence of pitch skip control may not be able to be suppressed, and as a result, the productivity of image output may be reduced. In addition, this apparatus also needs to have means for recognizing the frequency of occurrence of access requests and means for setting the priority of access requests based on the recognition result, which complicates software control. Becomes

Accordingly, the present invention provides an image processing apparatus having a multifunction function for processing a plurality of jobs in parallel without complicating a software control configuration or the like. By effectively utilizing the secondary storage device (improving access efficiency) and suppressing the occurrence of pitch skip control,
It is an object of the present invention to improve the productivity of image output.

[0013]

SUMMARY OF THE INVENTION The present invention has been devised to achieve the above object, and an image processing apparatus according to claim 1 comprises an input means for inputting image data, and an input means for inputting image data. First storage means for temporarily storing input image data, second storage means for storing image data stored by the first storage means, and image data in the first storage means being stored in the second storage means. Writing means for writing in the storage means, reading means for reading image data from the second storage means, and when a plurality of access requests to the second storage means conflict, the access request is transmitted to the writing means. Based on at least one of a write request to the read unit or a read request to the read unit and the type of the job that generated the access request.
Processing order determining means for determining a processing order for the plurality of access requests.

According to the image processing apparatus of the first aspect, when a plurality of access requests to the second storage unit conflict, the processing order determination unit determines the type of the access request (whether the request is a write request or a read request). ) And the type of the job that generates the access request, the processing order of these access requests is determined. In other words, the processing order determining means performs processing such that, for example, if an access request to the second storage means is a read request related to a job for performing image output, it takes precedence over other access requests (such as a write request). The order can be determined. Therefore, in the case where the processing order is determined in this way, even if a plurality of access requests are in conflict, the second storage means gives priority to reading out image data to be image-outputted over processing by other access requests. Will be done.

According to a third aspect of the present invention, there is provided an image processing apparatus comprising: an input unit for inputting image data; a first storage unit for temporarily storing the image data input by the input unit; and the first storage unit A storage unit that stores the image data stored in the first storage unit, a writing unit that writes the image data in the first storage unit into the second storage unit, and a readout of the image data from the second storage unit. Reading means to be executed, and at least one of an access request to the second storage means, a write request to the writing means or a read request to the reading means, and a type of a job which generated the access request. To
Data unit determining means for determining a processing unit of image data to be written or read in response to the access request.

According to the image processing apparatus of the third aspect, when image data is input by the input means, the first
After the temporary storage in the storage means, the second storage means stores the image data. At this time, the data unit determination unit determines whether the image is to be stored in the second storage unit based on at least one of the type of the access request (whether the request is a write request or a read request) and the type of the job that generates the access request. Determine the data processing unit. In other words, the data unit determination unit can determine, for example, that the processing unit (writing unit) of the image data is smaller for a write request to the second storage unit than for a read request. Become. Therefore, when the processing unit is determined in this way, the second storage means does not continue to occupy much time in the writing processing of the image data. Therefore, if there is a read request to the second storage unit after that, even if the writing of the image data of a certain processing unit is completed, even if the writing of all the image data is not completed, the image data of the image data by the read request is returned. Reading can be started.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image processing apparatus according to the present invention will be described with reference to the drawings. However, here, an example in which the present invention is applied to a digital multifunction peripheral having a multifunction function will be described.

[Explanation of Schematic Configuration in this Embodiment] A digital multifunction peripheral (hereinafter, referred to as a multifunction peripheral) in this embodiment
As shown in FIG. 1, an image input device 1, a compressor 2, a page buffer 3, a hard disk drive (hereinafter referred to as HDD) 4 as shown in FIG.
HDD-interface (hereinafter, interface is abbreviated as I / F) 5, decompressor 6, and image output device 7.
, MF (Multi Function) -I / F 8 and arbitrator 9
And a control unit 10. Note that the image input device 1, the compressor 2, the page buffer 3, the HDD-
I / F 5, decompressor 6, image output device 7, and MF-I /
F8 are connected to each other by the image bus A. It is assumed that a personal computer (hereinafter abbreviated as PC) 21 or a facsimile 22 is connected to the MF-I / F 8.

The image input device 1 is for inputting image data, and comprises an automatic document feeder 1a and an image reading device 1b.

The automatic document feeder 1a is a so-called ADF
(Automatic Document Feeder)
The original to be read is supplied to the image reading device 1b. However, this may be a double-sided automatic document feeder (DADF) provided with a mechanism for inverting and feeding a document in order to read a double-sided document. In the automatic document feeder 1a, the document is automatically transported by the "method of sequentially transporting the document from the first page". ".

The image reading device 1b comprises a scanner device or the like, and is a CCD (Charge Coupled Device).
An image drawn on a document to be read is optically read using an image pickup device such as the above, and image data as a set of electrical digital signals is obtained from the read result.

The compressor 2 performs data compression on image data read by the image reading device 1b. Since various data compression algorithms have been proposed, an appropriate one may be selected according to the type of image data to be handled, the required processing speed, the required compression ratio, and the like.
It is assumed that the compressor 2 generates an interrupt signal to the control unit 10 every time a predetermined amount of data compression is completed.

The page buffer 3 is a DRAM (Dynamic
It is composed of a semiconductor memory such as a random access memory (hereinafter referred to as Random Access Memory), and is image data (hereinafter, referred to as “compressed”) after data compression by
Compressed image data) or P through the MF-I / F8.
The image data transmitted from C21 or FAX22 is
This is a memory for temporarily storing.

The HDD 4 has a larger storage capacity than the page buffer 3 and reads (hereinafter simply referred to as "read") and writes (hereinafter simply referred to as "write") compressed image data at a lower speed than the page buffer 3. This is a secondary storage device that stores compressed image data as needed. Due to the mechanism of the HDD 4, the efficiency increases as the processing unit (data amount) of the compressed image data read or written at a time increases, and the time required for reading or writing per unit also decreases. This is because communication overhead and rotation waiting time do not occur. However, on the other hand, the absolute waiting time until the next read or write is performed becomes long. The HDD 4 may be composed of another large-capacity storage device such as an optical disk device.

The HDD-I / F 5 is a SCSI (Small Co.)
mputer System Interface)-I / F or IDE (Integr)
ated Drive Electronics) -corresponds to an I / F or the like, and based on an instruction from the control unit 10, sets an operation mode of the HDD 4, a transfer length of image data, and the like.
To control the reading and writing of compressed image data. At this time, the format of the data transferred on the image bus A is also converted to the format for the HDD 4. However, HDD-I / F
No. 5 can process only one access request (read request or write request) at a time. For example, during a read request, the next access request cannot be processed until the read is completed. In the HDD-I / F 5, when the reading or writing of the image data to the HDD 4 is completed, the control unit 1 is notified by an interrupt signal.
0 is notified.

The decompressor 6 restores the compressed image data once compressed by the compressor 2 and sequentially sends the compressed image data to the image output device 7. There are those which can be completely restored to the original image by the compression / decompression method (reversible compression) and those which cannot be restored (irreversible compression). Here, either method may be used. The decompressor 6 also generates an interrupt signal to the control unit 10 when the data decompression is completed.

The image output device 7 is composed of a printer or the like, and outputs the image data after data expansion by the expander 6 onto recording paper by an electrophotographic recording method using a semiconductor laser or the like. is there. This image output device 7
It is assumed that the recording paper is fed by a feed method called a pitch method. That is, the image output device 7 sequentially feeds recording paper from a paper storage tray (not shown) of the image output device 7 at regular intervals determined according to the paper size and mode. Further, by controlling the image output based on the pitch signal synchronized with the fixed interval, the image output and the sheet conveyance are synchronized while maintaining the independence of each control module.

An MF-I / F 8 is a control device for controlling an external device connected to the multifunction peripheral, and a PC (not shown)
An I / F, a decomposer for expanding code data from the PC 21 into bitmap data, a FAX-I / F, a storage device, and the like;
And transmits the data received on the image bus A to the PC 21 or the FAX 22. The MF-I / F 8 also has an image format conversion function (such as a 4-bit binary).

The arbitrator 9 has a PAL (Programmable Array).
Logic), and arbitrates image bus use requests from each resource connected to the image bus A, and according to a priority order set in advance for each resource.
Is permitted. The resources here are
Refers to the compressor 2, HDD-I / F5, MF-I / F12, decompressor 6, and the like. The arbitrator 9 has an arbitration unit of several bytes to several words.

The control unit 10 includes a CPU (Central Process
ng Unit) 11 and ROM (Read Only Memory) 12
, A RAM (Random Access Memory) 13, an interrupt controller 14, a communication controller 15, and a user interface (User Interface; hereinafter, referred to as U / I) 16. The components constituting the control unit 10, the compressor 2, and the HDD-I
/ F5, MF-I / F8 and arbitrator 9 are connected to each other by CPU bus B.

Of these, the CPU 11 functions as a main controller for controlling the entire multifunction peripheral. R
The OM 12 stores software (programs) necessary for the operation of the CPU 11 in advance. This R
As described in detail later, the software stored in the OM 12 determines what is necessary for the CPU 11 to control the job, the processing order of the access request to the HDD 4, and the processing unit of the image data at that time. And so on.

The RAM 13 is used as a work area (work memory) for the CPU 11. In addition,
The RAM 13 has a CPU as described in detail later.
11 stores an “HDD request registration table” necessary to determine the processing order of access requests to the HDD 4 and the like.

The interrupt controller 14 controls the compressor 2,
When there is an interrupt signal from the decompressor 6 or the HDD-I / F 5 or the like, it receives the interrupt signal and notifies the CPU 11 of the interrupt signal.

The communication controller 15 is for transmitting / receiving a command / status signal to / from the image input device 1 and the image output device 7. The U / I 16 is for detecting an instruction from the operator of the multifunction device and displaying the state of the multifunction device to the operator.

Next, an example of a processing operation in the multifunction machine configured as described above will be described.

[Explanation of Basic Processing Operation] First, among the basic processing operations of this multifunction peripheral, a general copy operation (copy job processing) is described in A4.
100% magnification of three originals of size and "Collate
The mode will be described with reference to the flowchart of FIG. “Collate Mode” is a mode for generating a designated number of copies in the same page order as the original. That is, in the "Collate Mode", if there are three originals, the first to third pages of the original are output one by one, and then the second to third and subsequent pages are sequentially output again. It has become.

In this multifunction peripheral, when the operator presses a start button (not shown) provided on the U / I 16 after the "Collate Mode" is designated, the U / I
The communication controller 15 connected to the
Notify 11 Upon receiving this notification, the CPU 11
Instruct the automatic document feeder 1a and the image reading device 1b to start reading a document (step 10).
1. Hereinafter, step is abbreviated as S).

When an instruction to start reading a document is issued, the automatic document feeder 1a and the image reading device 1b read the document (S102). First, the automatic document feeder 1a supplies the first one of the three document bundles to the image reading device 1b. When the first document is supplied, the image reading device 1b optically reads an image drawn on the document, and obtains image data of the first page from the reading result.

When the image reading device 1b obtains the image data of the first page, the compressor 2 receives the image data from the image reading device 1b and sequentially executes data compression according to a predetermined algorithm. At this time, the compressor 2 generates an interrupt signal each time the specified amount of data compression is completed, and notifies the CPU 11 via the interrupt signal to that effect. Then, the compressor 2 sends the compressed image data after the data compression to the page buffer 3 while following the arbitration by the arbitrator 9, and temporarily stores the compressed image data in the page buffer 3 (S103).

Thereafter, in this multifunction machine, the following 2
Execute two processes. In one process, the compressed image data in the page buffer 3 is transferred to the decompressor 6 in accordance with the arbitration by the arbitrator 9 (S104), and after the decompressor 6 performs data decompression, the decompressed image data is output as an image. Device 7
(S105). Note that the decompression operation and the image output operation at this time are scheduled based on the pitch signal described above.

In another process, the compressed image data in the page buffer 3 is stored in the HDD 4 under the control of the arbiter 9, the CPU 11 and the HDD-I / F 5 (S104). The storage of the compressed image data in the HDD 4 is necessary for outputting the second and subsequent copies of the “Collate Mode”.

Then, the same processing is repeated for the second and third originals (S106). When the processing for the third sheet of the original is completed, the image data of the first to third pages is output from the image output device 7 one by one on a recording sheet. When the set number of copies is one, the processing of the copy job ends here (S107). At this point, the automatic document feeder 1
The image reading device a and the image reading device 1b are vacant as resources, and can perform reading of the next document for a new job, that is, a so-called scan ahead operation.

However, if "Collate Mode" is designated, the image output for the second copy and thereafter (copy operation for the second and subsequent rounds) is started (S108). At this time,
In the HDD 4, the compressed image data of the first to third pages is stored and accumulated by the above-described first round copy operation (S104). Therefore, in this multifunction peripheral, when starting the second copy operation, first, the arbiter 9 and the CPU
11 and the HDD-I / F5,
Read the compressed image data of the first page from inside D4,
The compressed image data is transferred to the page buffer 3 (S
109). Thereafter, the compressed image data in the page buffer 3 is transmitted to the image output device 7 via the decompressor 6 while being controlled by the arbitrator 9, and the image output device 7 outputs the image (S110).

The same processing is repeated for the compressed image data of the second and third pages (S111). When the processing up to the third page is completed, 2
The round copy operation ends (S112). Regarding the image output of the third copy and thereafter (copy operation of the third and subsequent rounds), 2
This can be realized by repeating the same operation as in the round (S107 to S112). The above is the outline of the basic processing operation in the case of executing the copy job processing in “Collate Mode” in the multifunction peripheral.

However, in addition to the above-described copy job, the multifunction machine can also support a print job in which data received from the PC 21 is output by the image output device 7, for example. In this case, a print job request from the PC 21 is transmitted to the CPU 11 via the MF-I / F 8.
Is notified, the CPU 11 permits this only when it is determined that the system state is printable. And
The MF-I / F 8 notifies the PC 21 that data transfer is possible. Thus, transfer of data to be output from the PC 21 is started. Thereafter, the data from the PC 21 is temporarily stored in the page buffer 3 through format conversion by the MF-I / F 8 and data compression by the compressor 2. Thereafter, image output is performed in the same manner as in the case of a copy job. These differences are based on whether image data is input from the image reading device 1b or from the PC 21. FAX2
2 is processed in the same procedure as in the case of a print job. Further, it is possible to cope with a FAX transmission job and transmission of image data read by the image reading device 1b to the PC 21, but a detailed description thereof is omitted here.

[Explanation of Multi-Function Function] In the above description, the case where a copy job, a print job, a FAX reception job, and the like are individually executed has been described. However, this multifunction machine has a multi-function function. It is possible to execute multiple jobs simultaneously if resources allow. For example, for a copy job,
When the reading of the document is completed, the document can be read by the next job even if the image output for the document has not been completed. In this case, the output of the image data read by the next job is exactly the same as the above-described second and subsequent processing operations in the copy job. Similarly, it is also possible to receive data from the PC 21 or the FAX 22 and store it in the HDD 4 during the execution of the processing operation of the second and subsequent rounds of the copy job. As described above, a plurality of image data may flow on the image bus A at the same time, but the arbitrator 9 counts the right to use the image bus A based on the priority determined in advance for each resource of the request source. The control is performed at high speed in units of bytes to several words to cope with this.

[Description of Read / Write Control for HDD] Next, a characteristic control process in the present invention, that is, H which is the most characteristic point in the multifunction peripheral of the present embodiment.
Read / write control for DD will be described in detail.

This multi-function device has a multi-function function, and can process a plurality of jobs in parallel. Therefore, an access request (read request or write request) to the HDD 4 also occurs across a plurality of jobs.

However, since the HDD 4 performs reading or writing at a lower speed than a semiconductor memory or the like, real-time processing cannot be performed for an access request generated over a plurality of jobs. Therefore, an access request to the HDD 4 needs to be registered in an internal table “HDD request registration table” every time the access request occurs, because a plurality of requests are in conflict.

Here, the "HDD request registration table"
This will be described in detail. "HDD request registration table"
In order for the CPU 11 to determine the processing order of the access request to the HDD 4 and the processing unit of the image data at that time,
As shown in FIG. 3, it is stored in the RAM 13 of the control unit 10, and includes a request registration table 13a, and a read request information table 13b and a write request information table 13c linked to the request registration table 13a.

The request registration table 13a shows, for an access request to the HDD 4 issued from each resource, the type of the access request (read request or write request), priority (Priority), and detailed information of the access request. Information position (related table No.) in the read request information table 13b or the write request information table 13c that records the
And to record. Among them, the priority of the access request depends on whether the access request is a read request or a write request, as described in detail later.
The priority is determined according to a priority set in advance in accordance with both the type of the job related to the access request.

The read request information table 13b and the write request information table 13c are individually provided due to different information required for the read request and the write request.

In the read request information table 13b, for a read request to the HDD 4 issued from each resource, information (job No.) for specifying a job related to the read request, and compressed image data read out by the read request Information that identifies the page of the page (Page No.)
And is recorded. In the write request information table 13c, regarding the read request to the HDD 4 issued from each resource, in addition to the job No. and page No., the compression completion size, write completion size, The size during writing, the compression completion flag, and the page buffer address are recorded.

As described above, the "HDD request registration table" includes the request registration table 13a, the read request information table 13b, and the write request information table 13c.
The table may be composed of one table.

Next, a processing procedure for registering an access request to the HDD 4 in the “HDD request registration table” will be described with reference to the flowchart of FIG.

For example, reading of compressed image data from the HDD 4 in the second and subsequent cycles of the copying operation, a write request to the HDD 4 when an interrupt signal indicating that the compressor 2 has generated a fixed amount of compressed data is generated, and the like. When a read request or a write request from each resource to the HDD 4 occurs (S201), the CPU 11 first obtains the job type information (S202). This is information managed by the CPU 11 for each job as system information.
Specific job types are defined in advance according to the types of jobs that can be supported by the multifunction peripheral.
There are a copy job (first and second rounds, etc.), a print job of data from the PC 21, and the like (see FIG. 5).

When the job type information is obtained, the CP
U11 determines the priority of the access request based on the job type information and the type of the access request, that is, whether the request is a read request or a write request (S203). At this time,
The CPU 11 determines the priority of the access request from a “priority determination table” preset in the ROM 12 or the like.

The “priority judgment table” is, for example, as shown in FIG.
As shown in FIG. 7, priority levels are defined in advance according to the job type (job type) and the type of access request (read request or write request). The higher the priority.

More specifically, the read request always has the highest priority in any job type. this is,
The read request is a request for outputting an image on a recording sheet, and the recording sheet is fed within a predetermined time.
This is because it is necessary to complete the read as soon as possible in order to minimize the occurrence of pitch skip control. In the first cycle of the copy operation, the priority is similarly “1” in the case of a write request. In the first round, the image output on the recording paper is performed from the page buffer 3 and the first round is performed.
This is because it is necessary to quickly store the compressed image data in the HDD 4 in preparation for switching from the first round to the second round. When printing is performed while receiving data from the PC 21, the read request and the write request have the priority “1” for the same reason. Copy (read)
The job indicates a scan ahead, etc., and is a write to the HDD 4 when the image output device 7 is not empty, so the priority is set to “2” here. Below, PC
Receiving data from 21 is given priority "3" and receiving FAX is given priority "4".

The order of priority in the "priority judgment table" is determined by the operator based on the nature of the system.
6 may be arbitrarily changed. For example, P
In a system that wants to give priority to data reception from C21, the priority of data reception from PC21 is "2".
You may make it.

As described above, when the priority is determined based on the “priority determination table”, the CPU 11 issues an access request to the HDD 4 from each resource as shown in FIG.
The information is registered in the “HDD request registration table” in association with the determined priority (S204). And HDD-I / F
5 prepares for the case when the access request can be processed.

Next, the read or write by the access request registered in the “HDD request registration table”
A processing procedure when the process is executed by D4 will be described with reference to a flowchart of FIG.

In executing the access request registered in the “HDD request registration table”, the CPU 11 first
It is determined whether an access request to the HDD 4 can be issued (S301). There are two conditions, one is HD
D4 is not currently performing read or write processing, and the other is that there is an access request registered in the “HDD request registration table”.

When the read or write process that is already being performed in the HDD 4 ends, the HDD-I / F 5 generates an interrupt signal to that effect. Then, the interrupt controller 14 sends the interrupt signal to the HDD
Then, the CPU 11 is notified that the processing in step 4 has been completed. When this notification is received, the CPU 11 determines that an access request to the HDD 4 can be issued, searches the request registration table 13a of the “HDD request registration table”, and has the highest priority among them. In addition, the access request registered first is found (S302).

At this time, the CPU 11 determines whether the access request is a read request or a write request (S303). If it is a read request,
The CPU 11 acquires the job No. and page No. corresponding to the read request from the read request information table 13b linked to the request registration table 13a, and issues a read request in page units (S304). That is, CP
U11 sets the processing unit of the compressed image data read from the HDD 4 in page units. In response to this read request, the HDD 4 is caused to execute reading of the compressed image data.

On the other hand, if the access request is a write request, the CPU 11 obtains the priority of the write request from the request registration table 13a, and according to the priority, writes the compressed image data to be written at one time. Of the compressed image data to be written to the HDD 4 (S305). The determination of the processing unit is performed based on the “light size determination table”.

The "write size judgment table" is set in advance in the ROM 12 or the like in the same manner as the "priority judgment table". For example, as shown in FIG. Is specified. Specifically, the lower the priority of the write request, the smaller the amount of data to be written at one time. If the priority is “1”, the maximum size possible at that time is set as a processing unit. Is "4", the processing unit is 64 Kbytes. This is because by reducing the processing unit,
This is because the time required for the processing is shortened, and the waiting time can be reduced even when an access request with a higher priority is generated. However, this processing unit depends on the system requirements, the performance of the HDD 4 to be used,
What is necessary is just to determine an appropriate light size. The "light size determination table" may be changed by the operator from the U / I 16 as in the "priority determination table".

When the processing unit of the compressed image data to be written is determined, as shown in FIG. 6, the CPU 11 determines the processing unit, the job number and the job number acquired from the write request information table 13c linked to the request registration table 13a. Based on the page number and the address information of the page buffer 3, a write request for the determined processing unit is issued (S306). Then, in response to the write request, the HDD 4 executes writing of the compressed image data.

Further, when determining the processing unit of the compressed image data to be written, the CPU 11 registers the processing unit in the item “size during writing” in the write request information table 13c. Thereafter, when receiving an interrupt signal indicating that the writing has been completed, the CPU 11 registers the processing unit (data amount) registered in the “size being written” in the item “write completed size” in the write request information table 13c.
Is added, and the item of “size during writing” is cleared to zero.

Each time the CPU 11 receives an interrupt signal from the compressor 2 indicating that a certain amount of data has been compressed, the "compression completion size" in the write request information table 13c is read.
Is updated, and upon receiving an interrupt signal indicating that the data compression of all data has been completed, the final size of the compressed image data is recorded in the "compression completed size" field. The size of the compressed image data can be obtained by reading the designated register of the compressor 2 when receiving an interrupt signal indicating that the data compression is completed. And at the same time,
"Compression end flag" in the write request information table 13c
Is set to "1" which is a flag indicating that the data compression of all data has been completed.

It is needless to say that the CPU 11 deletes the corresponding access request from the “HDD request registration table” when the processing for the read request or the write request is completed.

FIG. 8 shows a processing operation example in the HDD 4 when the CPU 11 performs the above read / write control. This is an example of a case where reading of a document of the next job (scan ahead) is being performed while outputting an image in the second cycle of the copy operation.

According to the example shown in the figure, the HDD 4 preferentially executes the second read, and divides the image data read by the scan ahead during the idle time into processing units determined by the CPU 11 and writes the divided data. ing. By doing so, pitch skip control does not occur in a data decompression operation or an image output operation for outputting image data on recording paper. In addition, even if writing is performed in a vacant time, reading is performed in small processing units, so that reading for image output does not have to wait, and even if a plurality of jobs are executed in parallel. There is no reduction in productivity at the time of image output. In this example, the scan ahead is performed during the execution of the second copy, but the same applies to the reception from the PC 21 and the FAX 22.

Note that, here, the H
The case where the writing to DD4 is set to a uniformly small value has been described as an example. However, this is limited to only when a plurality of jobs are executed, and when only a single job is executed,
Write to HDD4 in as large a unit as possible,
The writing efficiency may be increased. Also, when a new job execution is requested in the single job execution state,
If the next job is accepted after the writing to the HDD 4 currently being executed is completed, it is easy to make a transition from the control mode for executing a single job to the control mode for executing multiple jobs. .

As described above, in the multifunction peripheral of the present embodiment, the type of access request to the HDD 4 (whether a write request or a read request) and the type of job related to the access request as in the first aspect of the present invention. , The priority of the access request is set in advance, and when a plurality of access requests conflict, the CPU 11 determines the processing order of the plurality of conflicting access requests according to the priority. ing. Therefore, if priorities are set in advance so that an access request for a job requiring an urgent process, such as a job for outputting an image in the image output device 7, is given priority over other access requests, the HDD 4 Means that, even if a plurality of access requests are in conflict, processing by an urgent access request is performed in preference to processing by another access request.

In particular, if the priority order is set so that a read request for outputting an image has a higher priority than another write request as in the second aspect of the present invention,
Even if a plurality of access requests conflict, the image output device 7
Read the compressed image data to be output with
The process is performed prior to the process based on another write request.

In other words, in this multifunction machine, even if an access request (read request or write request) to the HDD 4 conflicts by processing a plurality of jobs in parallel, the HDD 4 for outputting an image is used. The read of the compressed image data from the HDD 4 can be performed prior to the processing in the other HDD 4. This allows
The occurrence of the pitch skip control in the image output device 7 can be suppressed as much as possible, and as a result, a decrease in the productivity of the image output can be prevented. In addition, this multifunction peripheral achieves this by deciding the processing order in accordance with a preset priority order. Therefore, the multifunction peripheral performs arithmetic processing such as prediction of read time, read scheduling, and recognition of the frequency of occurrence of access requests. No need to do
There is no complication of software control.

Further, in the multifunction peripheral according to the present embodiment, as in the third aspect of the present invention, the CP according to the priority set in advance based on the type of the access request and the type of the job.
U11 determines the processing unit of the compressed image data to be read from or written to the HDD 4. For this reason, for example, such as a job for outputting an image in the image output device 7, the processing unit of an access request for a job requiring an urgent process is set to be larger than the processing unit of another access request. H
The DD 4 performs the process according to the urgent access request efficiently and in a short time.

In particular, according to the fourth aspect of the present invention, the HD
When writing to D4, if the processing unit of the compressed image data is made smaller than when reading,
Does not continue to be occupied for a long time in the write processing. Therefore, if there is a read request to the HDD 4 thereafter, even if the writing of all the compressed image data has not been completed, if the writing of a certain processing unit is completed, the reading of the compressed image data by the read request is started from that point. Will be able to start.

In other words, in this multifunction peripheral, even when a read request and a write request to the HDD 4 conflict with each other, the processing unit for performing writing is made smaller than that for reading, thereby enabling image output. Will not be kept waiting. Therefore, it is possible to minimize the occurrence of the pitch skip control in the image output device 7, and it is possible to prevent the productivity of the image output from lowering. In addition, if the read from the HDD 4 is preferentially executed in order not to generate the pitch skip control, even if there is a write request which is requested in parallel with the read request, the writing of the compressed image data by the write request is executed. However, according to this multifunction peripheral, it is possible to perform writing during a time when a read request is available by reducing the processing unit when performing writing. There is no delay in writing the compressed image data to. Furthermore, by deciding the processing unit in accordance with a preset priority order, there is no need to perform any arithmetic processing or the like, and the software control is not complicated.

Further, in the multifunction peripheral according to the present embodiment, the processing unit of a predetermined low priority order among the write requests is further reduced, as in the fifth aspect of the present invention. In addition, it is possible to reduce the processing unit related to an access request for a job that does not require urgent processing, and preferentially process another job that requires urgent processing. In other words, it is possible to prevent the occurrence of a time period during which the HDD 4 is not performing read or write while suppressing the occurrence of pitch skip control.
Access requests to the HDD 4 can be processed more efficiently, and as a result, effective use of HDD resources can be realized.

Further, if the processing unit is reduced only when a plurality of jobs are processed in parallel as in the invention according to the sixth aspect, during processing of a single job, that is, when an access request is If there are no conflicts,
Processing according to the access request can be performed efficiently and in a short time. In other words, it is possible to achieve both the prevention of a decrease in productivity when access requests conflict and the efficiency of processing when access requests do not conflict.

In the MFP according to the present embodiment, the HDD 4 stores the compressed image data after the data compression by the compressor 2 and stores the compressed image data in the The image output device 7 outputs the decompressed image data. That is, since the HDD 4 stores and stores the compressed image data, the time required for reading or writing can be reduced as compared with the case where the data is not compressed.
An access request to DD4 can be efficiently processed.

[0084]

As described above, according to the image processing apparatus of the present invention, the type of an access request to the second storage means (whether a write request or a read request) and the type of a job related to the access request are determined. The priority order of the access request is set in advance, and the processing order or processing unit of the access request to the second storage unit is determined according to the priority order.
Therefore, even when access requests to the second storage unit conflict with each other by processing a plurality of jobs in parallel, reading of image data from the second storage unit for performing image output is performed by another process. It can be done with priority. Therefore, it is possible to minimize the occurrence of the pitch skip control while realizing the effective use (improvement of the access efficiency) of the second storage means, which is one of the resources constituting the image processing apparatus. Can be prevented from lowering in productivity. In addition, since this is achieved by determining the processing order or the processing unit according to a preset priority, there is no need to perform arithmetic processing or the like, and the software control is not complicated.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of an example of an embodiment of an image processing apparatus according to the present invention.

FIG. 2 is a flowchart illustrating an example of a processing operation when a general copy operation is performed in the image processing apparatus illustrated in FIG. 1;

FIG. 3 is an explanatory diagram showing a specific example of an HDD request registration table in the image processing apparatus shown in FIG. 1;

4 is a flowchart showing a processing procedure when an access request to an HDD is registered in an HDD request registration table in the image processing apparatus shown in FIG.

FIG. 5 is an explanatory diagram showing a specific example of a priority determination table in the image processing device shown in FIG. 1;

FIG. 6 is a flowchart showing a processing procedure when the HDD executes an access request registered in the HDD request registration table in the image processing apparatus shown in FIG. 1;

FIG. 7 is an explanatory diagram showing a specific example of a light size determination table in the image processing device shown in FIG. 1;

8 is a timing chart showing an example of processing operation in the HDD when a read request and a write request conflict with each other in the image processing apparatus shown in FIG. 1;

FIG. 9 is a timing chart showing an example of a processing operation in the HDD when a read request and a write request compete with each other in the conventional image processing apparatus.

[Description of Signs] 1a: Automatic document feeder, 1b: Image reading device, 2
... Compressor, 3 ... Page buffer, 4 ... HDD, 5 ... HD
D-I / F, 6: expander, 7: image output device, 8: MF
-I / F, 10 ... Control unit, 11 ... CPU, 12 ... RO
M, 13 RAM, 13a request registration table, 13b
... Read request information table, 13c ... Write request information table

Claims (7)

[Claims] An input unit for inputting image data, a first storage unit for temporarily storing the image data input by the input unit, and a first storage unit for storing the image data stored by the first storage unit. 2 storage means, writing means for writing image data in the first storage means in the second storage means, reading means for reading image data from the second storage means, and second storage means In the case where a plurality of access requests conflict with each other, at least one of whether the access request is a write request to the writing unit or a read request to the reading unit, and a type of a job that generated the access request are determined. And a processing order determining unit for determining a processing order for the plurality of access requests. 2. The image processing apparatus according to claim 1, wherein the processing order determining means determines a processing order so that the read request has priority over the write request. 3. An input unit for inputting image data, a first storage unit for temporarily storing the image data input by the input unit, and a first storage unit for storing the image data stored by the first storage unit. 2 storage means; writing means for writing image data in the first storage means in the second storage means; reading means for reading image data from the second storage means; and second storage means Based on at least one of whether the access request to the writing unit is a writing request to the writing unit or a reading request to the reading unit and the type of the job that generated the access request, writing or reading is performed by the access request. An image processing apparatus comprising: a data unit determining unit that determines a processing unit of image data to be performed. 4. The image processing apparatus according to claim 3, wherein the data unit determination unit determines the processing unit of the image data according to the write request to be smaller than the read request. 5. The data unit determination means determines a processing unit for a predetermined low priority order among the write requests so as to be smaller than a processing unit for a high priority order. The image processing apparatus according to claim 3, wherein the image processing apparatus is an image processing apparatus. 6. The data unit determination means determines that a unit of processing for writing image data is made smaller when a plurality of jobs are processed in parallel than when a single job is being processed. The image processing apparatus according to claim 3, 4 or 5, wherein: 7. A compression unit for compressing image data input by the input unit and storing the compressed image data in the first storage unit or the second storage unit, and the first storage unit or the second storage unit stores the image data. Decompressing means for decompressing the compressed image data and outputting the decompressed image data to the output means.
7. The image processing apparatus according to 2, 3, 4, 5 or 6.