JP2002251318A - System controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a system controller capable of performing efficient memory allocation. SOLUTION: This system controller has two buses being a CPU bus and a bus for image transfer. A CPU 1, a ROM 2, a RAM 3, a bridge, etc., are connected to the CPU bus connected directly to the CPU. Also a bridge 6, an image memory 5, a DMAC 4, a scanner buffer 8, a plotter buffer 9, a NIC(network interface card) 7, a hard disk 10, etc., are connected to the bus for image transfer that mainly transfers image data. In this configuration, a minimum image memory amount needed to operate respective processes is calculated, an image memory of the calculated amount needed is also reserved in starting the system, and the image memory amount reserved by each process is dynamically changed by an event such as abnormal processing. Thus, a process never becomes inoperative even when a plurality of processes simultaneously operate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a system controller, and more particularly to a system controller of an image processing apparatus for managing a process execution environment for simultaneously operating a plurality of image input / output processing processes such as a copy process and a print process.

[0002]

2. Description of the Related Art Conventionally, a system controller is applied as a system controller of an image processing apparatus equipped with an image input / output engine such as a scanner or a plotter. More specifically, the MFP (Multi Function Pe
ripheral) machine.

In an image processing apparatus represented by an MFP,
Not only copy but also multiple processes can run. For example, it has a print function, a scan function, an image storage function, a facsimile function, a function of extracting a stored image from a network, and the like, and is configured to enable a plurality of process operations.

In such a controller of the image processing apparatus, the performance of the system is improved by simultaneously executing a plurality of processes. For example, in the print process and the scan process, the plotter and the scanner, which are the resources of the image processing apparatus, are not consumed by the processes at the same time, so that the processes can be operated in parallel. be able to.

[0005] Even when a fax is received during the execution of the copy process, the copy process uses scanner and plotter resources, whereas the image storage process by fax reception does not use a scanner or plotter. These processes can operate in parallel without using resources at the same time.

On the other hand, in such an image processing apparatus, an image memory for developing an image is prepared. However, when a plurality of processes operate in parallel, each process consumes the image memory at the same time. Therefore, when a certain process consumes a large amount of image memory, the image memory cannot be acquired even when another process requires the image memory, and the operation must be interrupted. is there.

[0007] As a result, the process cannot operate immediately. For example, when the process is an urgent process, there is a problem that the system may be broken.

To solve this problem, see, for example,
The invention disclosed in Japanese Patent No. 39324 proposes a system including a dedicated memory pool used by specific software and a general-purpose memory pool used by other software.

[0009]

However, in the above-mentioned prior art, when a plurality of processes occur at the same time and a large amount of general-purpose memory pool is consumed, the specific software cannot operate only with the dedicated memory pool. There is.

An object of the present invention is to provide a system controller in which, even when a plurality of processes are operating at the same time, each process can operate without interruption and memory can be efficiently allocated. With the goal. According to the system controller of the present invention, for example, it is possible to prevent an urgent process from becoming inoperable due to insufficient memory.

[0011]

In order to achieve the above object, a system controller according to the present invention provides an image processing apparatus in which a plurality of processes operate in a minimum amount of image memory required for each process to operate. Is calculated, and a required amount of image memory calculated at the time of system startup is reserved, and a change unit that dynamically changes the amount of image memory reserved by each process according to an event is provided.

According to a second aspect of the present invention, in the image processing apparatus in which a plurality of processes operate, the minimum amount of image memory necessary for operating each process is calculated before starting the system. It is characterized in that it has changing means for reserving the calculated required amount of image memory and dynamically changing the amount of image memory reserved by the process according to the quality of the image to be handled.

According to a third aspect of the present invention, in the image processing apparatus in which a plurality of processes operate, the minimum amount of image memory necessary for operating each process is calculated, and the system controller is activated when the system is started. It is characterized by having a changing means for reserving the calculated required amount of image memory and dynamically changing the amount of image memory reserved by the process according to the image size to be handled.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a system controller according to the present invention will be described in detail with reference to the accompanying drawings. Referring to FIGS. 1 to 9, there is shown an embodiment of the system controller of the present invention.

FIG. 1 shows a system controller 1 of the present invention.
1 shows an example of the overall configuration of FIG. The apparatus shown in FIG. 1 has two buses, a CPU bus and an image transfer bus. The CPU bus is a bus directly connected to the CPU.
OM2, RAM3, bridge, etc. are connected.

The image transfer bus is a bus for mainly transferring image data. The bus is connected to a bridge 6, an image memory 5, a DMAC 4, a scanner buffer 8, a plotter buffer 9, a NIC 7, a hard disk 10, and the like. I have. This bus is a bus that must transfer image data at high speed. Even if a general-purpose high-speed bus is used,
A bus designed to transfer image data efficiently may be used.

The bridge 6 mediates the CPU bus and the image transfer bus, absorbs the difference in speed and bus width between the two buses, and performs endian conversion and the like. For example, when the CPU 1 accesses the image memory 5, the bridge 6 converts the CPU bus access cycle by the CPU 1 into an image transfer bus access, thereby realizing the access to the image memory 5.

The image memory 5 is an area for storing image data. It stores image data input from an image input unit such as a scanner, and image data sent from a network through the NIC 7. The image data may be any type of image, for example, images of various formats such as black and white / color, binary / multi-valued, compressed / uncompressed, and low / high resolution.

The image data stored in the image memory 5 is transferred to a plotter for printing, transmitted over a network through the NIC 7, or stored on the hard disk 1
Processing such as saving to 0 is performed.

A DMAC (DMA Controller) 4 is a controller for transferring image data flowing on an image transfer bus at a high speed. For example, a process to transfer a large amount of data at a time, such as writing to a designated area, is performed. The address and transfer size on the frame memory can be
Specify it in the MAC.

NIC (Network Interface Controller) 7
Is a module that controls the I / F with the network.
It receives image data and other data sent from the network, and performs a process of flowing data to the image transfer bus in accordance with a request from the bus. In addition, processing for transmitting data to the network is also performed.

The scanner engine 12 is a module for inputting an image, and transfers input image data to a scanner buffer via a scanner I / F. The scanner buffer 8 temporarily stores the image data sent from the scanner engine 12, and outputs the data according to the bus cycle of the image transfer bus.

The plotter engine 13 is a module for outputting an image. The image data sent from the plotter buffer 9 is taken in via a plotter I / F and printed. The plotter buffer 9 temporarily stores the image data sent from the image transfer bus, and outputs the data according to the speed of the plotter I / F. Hard disk 10
Is a storage device for storing images.

Next, an example of the operation will be described. FIG. 2 shows an operation example of a copy process in which an image captured by the scanner engine 12 is stored in the image memory 5 and data in the image memory 5 is output to the plotter engine 13.

First, the scanner engine 12 is requested to start scanning (step S1), and the image data is stored in the scanner buffer 8. Subsequently, the DMAC 4 is requested to start DMA transfer (step S2),
4 for the scanner buffer 8
Is transferred to the image memory 5. This transfer is performed using an image transfer bus.

All the images are read by the scanner, and the image data is transferred until all the image data is stored in the image memory 5 (steps S3 and S4). When the transfer of all the image data is completed (step S4 /
Y), requesting the scanner engine 12 to end the scan (step S5), and subsequently requesting the DMAC 4 to end the DMA transfer (step S6). Thus, the image transfer from the scanner engine 12 to the image memory 5 is performed.

Next, the DMAC 4 is requested to start DMA transfer (step S7), and subsequently, the plotter engine 13 is requested to start printing (step S8). As a result, the image data is transferred from the image memory 5 to the plotter buffer 9. This transfer is performed using an image transfer bus.

All the image data on the image memory 5 is transferred, and the image data is transferred until all the image data is output to the plotter (steps S9 and S1).
0). When the transfer of all the image data is completed (step S10 / Y), the DMAC 4 is requested to finish the DMA transfer (step S11), and then the plotter engine 13 is requested to finish the print (step S12). As described above, the image transfer from the image memory 5 to the plotter engine 13 is performed.

Next, the assignment of the image memory 5 will be described. For example, it is assumed that a process A, a process B, and a process C operate in the image processing apparatus. First, at the time of activation of the present apparatus, the minimum amount of image memory required by each process is calculated. The size of the image memory required by each process differs depending on the type of process and the type of image data to be handled.

For example, in a print process for developing and outputting an image in band units, an image memory that can develop at least an image for one band is required. Similarly, the process of developing and outputting images in page units requires at least one page of image memory. These are the minimum required memory capacities. For a process to operate comfortably in a normal operation, for example, the process A needs one page of image memory, and the process B needs several pages of image memory.

In a process in which a compressed image is expanded in an image memory and printed using a decompression function of hardware at the time of output, an image memory that can hold a compressed image is required. If the image to be processed is a process of only monochrome images, only one plane of image memory is required. However, a process of handling color images may require four planes of image memory.

A process that also handles a high-definition image requires more image memory than a normal image. As described above, the required size of the image memory differs depending on the type of the process, the type of the image handled in the process, and the like. Hereinafter, for example, an example in which the process A, the process B, and the process C require at least the following image memory capacity will be described.

Process A is a printing process for developing and outputting an image for each band, and requires at least one band of image memory. Process B is 1
This is a print process for developing and outputting an image for each page, and requires at least one page of image memory. Process C is a facsimile receiving process of receiving a fax document compressed for each page and storing it in an image memory, and it is assumed that at least one page of image memory is required. It is assumed that the minimum required image memory amount obtained in this way is, for example, 2 MB in process A, 5 MB in process B, and 1 MB in process C.

Next, at the time of system startup, the minimum image memory required for each process is allocated as a dedicated image memory for each process. The remaining image memory is allocated as a free image memory that can be used in all processes.

Thus, when the system is started, the image memory for process A, the image memory for process B, the image memory for process C, and the free image memory are allocated as shown in FIG. The image memory assigned to each process is an image memory dedicated to that process. For example, the image memory for process A is prohibited from being accessed by other processes.

When the process A is executed, the image memory is reserved by a capacity required by the process A. If the process A normally uses a 10 MB image memory, an 8 MB image memory is reserved from the 2 MB process A image memory and the free image memory as shown in FIG.

Next, when the process B is executed during the execution of the process A, the image memory is reserved by a capacity required by the process B. If the process B normally uses a 20 MB image memory, a 15 MB image memory is reserved from the 5 MB process B image memory and the free image memory. At this time, when the unused area of the free image memory is less than 15 MB, the unused area currently in the free image memory is reserved as the image memory of the process B. For example, if the unused area is 10 MB as shown in FIG.
A total of 15 MB including the free image memory of 0 MB is allocated to the process B.

In this case, the process B has not obtained an image memory having an optimum capacity, but is operable because the minimum memory capacity required for the operation of the process can be secured. Further, when the process C is executed simultaneously, the image memory required by the process C is reserved. Since the free image memory is currently reserved for process A and process B, there is no area to be allocated to process C. Therefore, only the image memory for process C is allocated as shown in FIG. In this case, although the process C has not obtained an image memory having an optimal capacity, the process C is operable since the minimum memory capacity required for the operation of the process is secured.

As described above, in the situation where the process A, the process B, and the process C operate at the same time, since the minimum required image memory is secured, the simultaneous operation becomes possible. Further, when the priority of the process A becomes high and it is necessary to operate at the highest speed in the system, the whole area of the free image memory may be used in the process A. At this time, the image memory allocated to the process A is 2 MB.
And the entire area of the process A image memory and the free image memory.

At this time, the image memory for the process B and the image memory for the process C have the minimum memory capacity that can be executed respectively, the free image memory that can be used by the process A becomes the maximum, and efficient memory allocation is performed. Becomes possible.

In this state, process B and process C
Is executed, each process can be executed because the minimum image memory necessary for executing each process is secured.

As described above, the minimum image memory amount necessary for each process to operate is calculated,
By reserving a required amount of image memory calculated at the time of system startup, each process can operate reliably without interruption and efficient memory allocation can be performed. Further, even when an abnormal processing event occurs, the image memory allocation is changed.

For example, it is assumed that a server process for a client accessing the image processing apparatus through a network is operating in the image processing apparatus, and that an image memory required by the server process has been reserved. At this time, if the network goes down for some reason, the server process does not operate, the image memory reserved by the server process is not used, and the reserved memory is wasted.

When an image input device such as a scanner becomes unusable due to an abnormality, the scanning process becomes inoperable, and the reserved memory is not used and the reserved memory is wasted. Would.

Therefore, when a process which has become inoperable due to a certain abnormal processing event reserves the image memory, the image memory is released so that the memory can be efficiently used without wasting wasteful memory. Make memory allocation.

For example, as shown in FIG. 3, a reserved area of a process is allocated, a process A is a print process, a process B is a scan process, and a process C is F.
Assume that this is an AX process. At this time, if the scanner becomes unusable due to some abnormality, the process B itself becomes inoperable. Therefore, the image memory for the process B is released as shown in FIG. 7 to prevent the memory from being wasted.

Process A, which is a printing process, can operate even when the scanner is abnormal because it does not use a scanner. Free image memory increases by opening the image memory for process B, and the process can operate in a more optimal memory environment. Become.

When the abnormality processing event is canceled, that is, when the scanner abnormality is canceled, the process B which is a scanning process becomes operable.
The image memory for the process B is newly reserved so that the process B can operate in an optimal memory environment.

At this time, if there is not enough free image memory to be allocated to the image memory for process B, the process waits for memory allocation to process B until another process releases the free image memory. Reallocate the image memory.

Next, the image memory allocation according to the second aspect of the present invention will be described. As shown in FIG. 3, it is assumed that an image memory for process A, an image memory for process B, and an image memory for process C are reserved.

Process A is usually performed at a resolution of 600 dpi.
It is assumed that the printing process is to develop and output an image for each band. At this time, the image memory for process A has 1
The size is large enough to store the image for the band.

An image of 600 dpi can be output with the memory allocation as it is, but if the resolution in the main scanning direction becomes 1200 dpi in a high image quality mode or the like, the amount of image memory required for one band increases. . Therefore, if the free image memory is being used by another process in the current assignment, the process A cannot be executed. Therefore, in order to output an image of 1200 dpi, only the image memory required by the process A at the minimum is reserved as the image memory for the process A.

If the image size of one band is doubled, as shown in FIG.
Change to reserve B. This makes it possible to execute even when another process is using the entire free image memory. If an image of 300 dpi is output, the minimum required image memory of the process A is 1 MB, and the image memory for the process A is changed to 1 MB as shown in FIG. Thus, depending on the quality of the image,
By dynamically changing the amount of image memory reserved by each process, the operation of the process can be guaranteed.

Here, the difference in resolution has been described as an example, but the quality may be lowered due to the difference in color image or monochrome image, or the thinning process. For example, when the color toner runs out during the printing process of a color image, there is a method of substituting the printing of a monochrome image. At this time, printing in monochrome is continued until a color toner supply event occurs. Thus, by changing the amount of image memory required for the print process from the amount of memory required for color images to the amount of image memory required for monochrome images, printing in an optimal memory environment can be realized.

In a process in which the image quality is degraded due to the thinning process or the like, it is sufficient to reserve an image memory amount required by the process for the thinned image. So by changing the amount of image memory,
Printing in an optimal memory environment can be realized.

Next, the operation of the present invention will be described. As shown in FIG. 3, it is assumed that an image memory for process A, an image memory for process B, and an image memory for process C are reserved.

It is also assumed that process B is a print process for developing and outputting an image for each page. At this time, the image memory for the process B is large enough to store an image for one page. For example, it is assumed that an image memory that can store an A3 size image is reserved.

When printing an image smaller than the A3 size, an image for one page can be held in the image memory for the process B, so that printing is possible. At this time, if the A3 paper runs out on the paper feed tray, the printout of the A3 paper becomes impossible at that time,
Even if the A3 size image memory is reserved, it is useless.

Therefore, an image memory amount that can hold the image of the maximum paper size currently on the paper feed tray is reserved as the process B image memory. For example, B4 paper in tray 1, A4 paper in tray 2, B
If 5 papers are set, the maximum paper size is B
If the image memory for B4 size is reserved for four papers, the printing process of the papers currently on the tray can all be operated. When A3 size paper is replenished,
By returning the image memory for the process B to the original size, the print process of the A3 size can be operated.

As described above, by dynamically changing the amount of image memory reserved by each process according to the size of the image, the operation of the process can be guaranteed, and the process can be executed in a more optimal memory environment. Becomes possible.

In an image processing apparatus in which a plurality of processes operate, the minimum amount of image memory necessary for operating each process is calculated, and the required amount of image memory calculated at system startup is reserved. By doing so, it is ensured that each process operates without interruption.

When each process requires an image memory larger than the conventional reserve amount or an image memory smaller than the conventional reserve amount due to an event such as abnormal processing, the process is reserved. By dynamically changing the amount of image memory
In addition to ensuring that each process operates without interruption, efficient memory allocation can be performed.

When the amount of image memory required by each process changes according to the quality of the image to be handled, each process is interrupted by dynamically changing the amount of image memory reserved by the process. In addition to guaranteeing reliable operation, efficient memory allocation can be performed.

Further, when the amount of image memory required by each process changes according to the image size to be handled, the amount of image memory reserved by the process is dynamically changed, so that each process is not interrupted. In addition to guaranteeing reliable operation, efficient memory allocation can be performed.

[0065]

As apparent from the above description, according to the system controller of the present invention, even when a plurality of processes are operating at the same time, the minimum memory required by each process is secured. So that the process does not become inoperable. Further, even when the process operates, the memory size allocated to the other inactive processes is the minimum, so that the memory can be used efficiently. Further, since the process dynamically changes the reserved amount of image memory due to an event such as an abnormal process, the system can be operated more efficiently without wasting memory.

According to the second aspect of the present invention, the amount of reserved image memory is dynamically changed depending on the quality of the image to be handled, so that the memory is not wasted.
The system can be operated more efficiently.

According to the third aspect of the present invention, the amount of reserved image memory is dynamically changed depending on the size of the image to be handled, so that the memory is not wasted and the system operates more efficiently. Can be done.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a system controller of the present invention.

FIG. 2 is a flowchart illustrating an operation example of a copy application.

FIG. 3 is a diagram illustrating a configuration example of an image memory map as a memory allocation at the time of activation.

FIG. 4 is a diagram showing a configuration example of an image memory map in a process A reserve state.

FIG. 5 is a diagram illustrating a configuration example of an image memory map in a process A and a process B reserved states.

FIG. 6 is a diagram showing a configuration example of an image memory map in a process A, a process B, and a process C reserved state.

FIG. 7 is a diagram illustrating a configuration example of an image memory map when a process A and a process C allocate a memory;

FIG. 8 is a diagram showing a configuration example of an image memory map in a memory allocation state at the time of outputting a 1200 dpi image.

FIG. 9 is a diagram showing a configuration example of an image memory map in a memory allocation state when outputting a 300 dpi image.

[Explanation of symbols]

 1 CPU 2 ROM 3 RAM 4 DMAC 5 Image memory 6 Bridge 7 NIC 8 Scanner buffer 9 Plotter buffer 10 Hard disk 11 Controller 12 Scanner engine 13 Plotter engine

Claims (3)

[Claims] In an image processing apparatus in which a plurality of processes operate, a minimum amount of image memory necessary for operating each process is calculated, and the required amount of image memory calculated at system startup is reserved. And a changing means for dynamically changing the amount of image memory reserved by each process according to an event. 2. In an image processing apparatus in which a plurality of processes operate, a minimum amount of image memory necessary for operating each process is calculated, and the required amount of image memory calculated at system startup is reserved. And a changing means for dynamically changing the amount of image memory reserved by the process according to the quality of the image to be handled. 3. In an image processing apparatus in which a plurality of processes operate, a minimum amount of image memory required for operating each process is calculated, and the required amount of image memory calculated at system startup is reserved. And a changing means for dynamically changing the amount of image memory reserved by the process according to the image size to be handled.