JP2002211050A - Method, apparatus and system for outputting image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer which outputs by carrying out a drawing process inexpensively, easily and at high speeds, and other image output apparatus. SOLUTION: The printer 100 as an image output apparatus has a CPU 13 for carrying out the drawing process, e.g. by software, and a drawing accelerator 115 for carrying out the drawing process at high speeds, e.g. by hardware. The CPU 113 interprets a drawing command based on an output command from a host computer, and makes the drawing accelerator 115 execute the drawing process, e.g. from a head block of a process object region of the drawing command. At the same time, the CPU 113 itself carries out the drawing process, e.g. from a terminal block of the process object region of the drawing command. When a sum of regions to which the drawing process by each of the drawing accelerator 115 and the CPU 113 is completed becomes equal to the process object region of the drawing command, the CPU 113 terminates the processing the drawing command.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image output method, an image output apparatus, and an image output system for interpreting and outputting a drawing command based on an output command from an information processing device.

[0002]

2. Description of the Related Art The prior art is disclosed in, for example,
No. 74608 discloses a processing distribution means for distributing a predetermined processing request related to image processing to one processor selected from a plurality of processors, a runtime library for performing a specific image operation, and a runtime library. Means for estimating the processing load corresponding to each image operation of
When an image operation included in the runtime library is called during the target processing, prior to the start of the operation, the load estimating means calculates a processing load, and based on the calculated processing load, the processing distributing means determines a processor to distribute the processing unit. Thus, a multiprocessor image processing device that optimally distributes the load to each processor has been proposed.

For example, Japanese Patent Application Laid-Open No. H11-338651 proposes a hardware circuit dedicated to printer control that is interposed between a host device and a printer. Here, the printer control dedicated hardware circuit interposed between the host device and the printer includes a command analysis circuit, an image data processing circuit, a memory control circuit, a command buffer memory, a data buffer memory, a command generation circuit, and the like. At least a part of the data processing performed by the CPU of the host device or the CPU of the printer,
By using a dedicated hardware circuit, the load on the CPU can be reduced, and in particular, the CPU of the printer can be made low-performance and inexpensive. The processing speed of the dedicated hardware circuit is, for example, C
Because it is faster than PU, high-speed printing is possible,
In addition, this dedicated hardware circuit realizes printer control that is less expensive than a conventional high-speed printing system equipped with a high-speed CPU.

[0004]

In the prior art, the multiprocessor image processing apparatus calculates the processing load and distributes the processing requests to the selected processor based on the calculated processing load, thereby distributing the processing to each processor. It can be performed under appropriate load distribution, but it is necessary to prepare a runtime library and estimate the load, and the processing time calculated from the estimated load is different from the actual processing time, which is not desirable There is a possibility of load distribution.

In the conventional system in which a printer control dedicated hardware circuit as a drawing accelerator is interposed between a host device and a printer, the following method is used particularly when a plurality of image output devices share a drawing accelerator. Inconvenience occurs. In other words, when a certain image output device performs a drawing process using a drawing accelerator and the drawing accelerator is performing a drawing process according to a request from another image output device, it must wait for the drawing accelerator to complete the process. No. Further, when the signal line connecting the image output device and the drawing accelerator is in a high load state, performing the drawing process with the drawing accelerator may be slower than performing the drawing process with the processing unit in the image output device.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and a first object of the present invention is to provide an image output method, an image output apparatus, and an image output system capable of performing drawing processing easily and at high speed. It is in.

A second object of the present invention is to provide an image output system capable of performing a high-speed drawing process even when a signal line connecting the image output device and the drawing accelerator is under a heavy load.

[0008]

The main feature of the image output method of the present invention is to perform a drawing process in parallel on the processing target area of the drawing command from the head side and the end side, and to output the drawing processing result. And

Another image output method according to the present invention mainly performs a drawing process independently and in parallel with a processing target region of a drawing command, and outputs a drawing process result of a process which has been completed earlier. Features.

An image output apparatus according to the present invention includes first processing means such as a CPU, and second processing means such as a drawing accelerator operable independently of the first processing means. The processing means interprets the drawing command and sends the processing command to the second processing means, and performs a drawing process on the processing target area of the drawing command from, for example, the end side, and the second processing means performs processing from the first processing means. The main feature is that, in response to a processing instruction, drawing processing is performed on the processing target area of the drawing command from, for example, the front end side.

In the image output system of the present invention, an image output device and a drawing accelerator exist on, for example, a network, and the image output device interprets a drawing command, sends a processing command to the drawing accelerator, and The drawing accelerator performs the drawing process of the command, and the drawing accelerator receives the processing command from the image output device, and similarly performs the drawing process of the drawing command in parallel with the image output device. The image output device is one of the image output device and the drawing accelerator. The main feature is to reflect the processing result of the processing that has been completed earlier.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[Embodiment 1] In this embodiment, based on an output command from a computer as an upper information processing apparatus,
It is intended for a single printer, which is an image output device that performs drawing processing and outputs. The printer has a built-in or external drawing accelerator for performing drawing processing in the same manner as the printer.

FIG. 1 shows a block diagram of an example of the overall configuration of the present embodiment. In the figure, a printer 1 as an image processing device
00 is a host computer 10 as an upper information processing device.
It is connected to the. The connection form between the printer 100 and the host computer 10 is arbitrary, and for example, is directly connected by a cable or a network. Printer 10
0 is largely divided into a printer controller 110 and a print engine 120. The printer controller 110 has a host computer interface (hereinafter referred to as host I).
/ F) 111, memory 112, CPU (first processing means) 113, print engine interface (hereinafter, referred to as
A print engine I / F 114 and a drawing accelerator (second processing means) 115 are connected to each other by an internal bus 116.

The host I / F 111 is an interface circuit between the host computer 10 and the printer controller 110. In this embodiment, the host I / F 111 compresses and sends data to the printer 100 in order to reduce the amount of data to be transferred to the printer 100. It is assumed that the apparatus has a function of expanding an incoming output command or the like. The memory 112 is a non-volatile memory, and stores a processing program of the CPU 113, an output command from the host computer 10, an intermediate processing result in the CPU 113 and the drawing accelerator 115, a processing result, and the like. The CPU 113 controls the operation of the entire printer and the like, loads a necessary program from the memory 112, and performs drawing processing by software. Note that C
The PU 113 can also have a function of performing part or all of the drawing processing by hardware. The drawing accelerator 115 performs drawing processing at high speed by dedicated hardware. Contrary to the CPU 113, the drawing accelerator 115 can perform part or all of the drawing processing by software. Print engine I / F114
Denotes the printer controller 110 and the print engine 12
The interface circuit is connected to the print engine 120 and outputs image data (print data) as a processing result in the memory 112 to the print engine 120.

FIG. 2 shows a configuration example in the memory 112.
The memory 112 includes an output command storage area 201 for storing an output command from the host computer 10, a CPU drawing result temporary holding area 202 for storing a drawing result processed by the CPU 113, and a drawing accelerator for storing a drawing result processed by the drawing accelerator 115. A rendering result temporary storage area 203, an output information storage area 204 for storing information (print data) to be output to the print engine 120, a processing status storage area 205 for storing the rendering processing status of the rendering accelerator 115, and It is divided into areas such as a parameter storage area 206 for storing various parameters. The parameters in the parameter storage area 206 can be changed from the host computer 10 as needed. Note that the memory 112 has a CPU 113
The program and other programs necessary for the drawing process in FIG. 2 are also stored, but are omitted in FIG.

FIG. 3 shows a configuration example of the drawing accelerator 115. The drawing accelerator 115 includes a bus interface (hereinafter, bus I / F) 301, a control unit 302, a color conversion processing unit 311, a BG / UCR processing unit 312, a γ conversion processing unit 313, a scaling processing unit 314, and a halftone processing unit 315. Etc. A bus I / F 301 is an interface circuit with the internal bus 116 of the printer controller 110. The control unit 302 controls the operation of each of the processing units 311 to 315. The control unit 302 controls the DMA (Direct Memory)
Access) function, and via the bus I / F 301, the C
The memory 112 can be accessed independently of the PU 113. The color conversion processing unit 311 converts the RGB image data into CMY image data. BG / UCR processing unit 3
Reference numeral 12 generates a K signal from CMY image data and removes undercolor. The γ conversion processing unit 313 performs printer γ correction processing on the CMYK image data after the BG / UCR processing. The scaling unit 314 performs enlargement / reduction processing as necessary. The halftone processing unit 315 performs CMY after gamma correction and scaling processing.
Pseudo halftone processing such as dither processing and error diffusion processing is performed on the K image data.

Note that the drawing accelerator 115 may be provided with a memory attached to the control unit 302 and the like, and a drawing accelerator result temporary holding area and a processing state holding area may be secured in the memory and read from the CPU 113. In addition, the order of the drawing processing need not be as shown in FIG. 3. For example, a configuration in which the scaling processing is performed before or after BG / UCR or after halftone processing may be employed.

First, an outline of the operation of FIG. 1 will be described with reference to FIGS. For example, when the printer 100 is started up, the CPU 113 loads a program and the like necessary for the drawing process from the memory 112 and fetches necessary parameters from the parameter storage area 306. Also in the drawing accelerator 115, the control unit 302 controls the bus I / F 30
1 to access the memory 112, fetch necessary parameters from the parameter storage area 306, and set them in the processing units 311, 312, 313 and the like.

The host computer 10 creates a drawing command based on a command from a user (not shown) or the like, and
An output command is sent to the printer 100 so that image drawing processing is performed based on the drawing command and output. The output command generally includes a control command and a plurality of drawing commands. In the control instruction,
For example, a job start, a job end, a page start, a page end, and the like are designated. At the page start, a size of a print area, monochrome / color, resolution, and the like are designated. Each drawing command specifies an object (image data) to be processed, enlargement / reduction, and the like. At any time, ROP (Raster Operati
on) Specify the processing.

The host I / F 111 in the printer 100
Writes the output command received from the host computer 10 into the output command storage area 201 of the memory 112 and notifies the CPU 113 that the output command has been received from the host computer 10. The host I
In / F111, if the output command sent from the host computer 10 is compressed (for example, the image data of the drawing command generally takes a compressed format), it is decompressed and written to the memory 112.

The CPU 113 extracts control commands from the output instructions written in the output instruction storage area 201 of the memory 112, and sequentially extracts drawing instructions to be processed. At the same time, the CPU 113
A processing instruction is issued to 5. In response to this, the drawing accelerator 115 also outputs the output command storage area 2 of the memory 112.
The control instruction is extracted from the output instruction written in 01, and
Further, under the control of the CPU 113, drawing commands to be processed are sequentially extracted.

Here, the CPU 113 and the drawing accelerator 115 store the output command storage area 201 of the memory 112.
The host I / F 111 stores the output command received from the host computer 10 in the output command storage area 2 of the memory 112.
It is also possible to start before all the writing to 01 is completed. Thereby, processing can be performed at higher speed. It is also possible to include a control command in the processing command issued from the CPU 113 to the drawing accelerator 115. Thus, the drawing accelerator 115 can omit the process of retrieving the control command from the memory 112 again.

The CPU 113 interprets the drawing command fetched from the output command storage area 201 of the memory 112, executes a drawing process on the object (image data) from, for example, the end side of the processing target area, and stores the processing result in the memory 11
2 is stored in the CPU drawing result temporary holding area 202. In the drawing accelerator 115, similarly, the image data of the drawing command extracted from the output command storage area 201 of the memory 112 is subjected to drawing processing from, for example, the top side of the processing target area, and the processing result is stored in the drawing accelerator drawing of the memory 112. While storing the result in the temporary storage area 203,
The processing status is sequentially set in the processing status holding area 205.
Here, it is arbitrary whether the CPU 113 or the drawing accelerator 115 executes the drawing process from the head or the rear end of the processing target area, and may be determined in advance, for example.

When the drawing processing is completed for the object (image data) of one drawing command, the CPU 113
The drawing processing results of the CPU drawing result temporary holding area 202 and the drawing accelerator drawing result temporary holding area 203 of the memory 112 are overlapped with the previous information in the output information storage area 204 by the ROP processing.
4 is updated. The information in the output information storage area 204 is initially empty (all clear), for example. Hereinafter, the same drawing process is repeated for each drawing command of the output command.

The print engine I / F 114 sends the processing result information (print data) of the output command stored in the output information storage area 204 of the memory 112 to the print engine 120 according to an instruction from the CPU 113 or the like. The print engine 120 prints based on the processing result of the output command received from the print engine I / F 114.

FIG. 4 shows a processing flow example of the drawing processing in the present embodiment. FIG. 4 shows a processing flow for one drawing command, which is repeated for each drawing command included in the output command.

The CPU 113 extracts a drawing command from the output command written in the output command storage area 201 of the memory 112 (step 401), and issues a processing command to the drawing accelerator 115 to process the drawing command (step 402). .

The drawing accelerator 115 is a CPU 113
(Step 421), the drawing processing of the drawing command is performed until the drawing processing of the drawing command is completed (step 422) or until the drawing processing stop command is received from the CPU 113. Drawing accelerator drawing result temporary holding area 20 in memory 112
3 is stored.

The drawing processing by the drawing accelerator 115 is performed as follows. Drawing accelerator 115
The control unit 302 converts the object (image data) of the drawing command from the output command stored in the output command storage area 201 of the memory 112 to a predetermined block (for example, one line) from the output command via the bus I / F 301. )
Reading (step 423), the processing units 311 to 315 are sequentially operated. First, in the color conversion processing unit 311,
In order to obtain visually the same output between the host computer 10 and the printer 100, image data in RGB format
The image data is converted into Y-format image data (step 424). Next, the BG / UCR processing unit 312 performs black plate generation and undercolor removal, and converts the CMY format image data into CMYK format image data (step 425). Next, in the γ conversion processing unit 313, the CMYK image data is
The density is converted for each CMYK plate so as to have a density characteristic suitable for 00 (step 426). Then, if necessary,
A scaling process is performed by the scaling unit 314 to convert the CMYK image data into an appropriate size (step 42).
7). Next, halftone processing is performed by the halftone processing unit 315, and the CMYK image data is converted to have a color depth suitable for the print engine 120 (step 428). Note that the order of the drawing processing does not have to be this order. The control unit 302 stores the processing result passed through the processing units 311 to 315 in the drawing accelerator drawing result temporary holding area 203 of the memory 112 via the bus I / F 301 (step 429). The processing status holding area 205 determines whether the processing of the part has been completed.
(Step 430).

After that, when the drawing process of the object of the drawing command is not completed, or when a command to stop the drawing process is not received from the CPU 113, the control unit 302 of the drawing accelerator 115 reads the object from the output information storage area 201 of the memory 112. The next predetermined block is read from the head of the object of the drawing command, and each of the processing units 311 to 311 is read.
The drawing process is similarly performed on No. 15.

As described above, the drawing accelerator drawing result temporary holding area 203 and the processing status holding area 205
Instead of securing it in the memory 112, it may be secured in a memory in the drawing accelerator 115 that can be read from the CPU 113. Thereby, the drawing accelerator 1
15 can write its own processing result at high speed.

On the other hand, after instructing the drawing accelerator 115 to process the drawing command, the CPU 113 transfers the object (image data) of the drawing command from the output command storage area 201 of the memory 112 from, for example, the end side of the processing target area. Reading is performed for each predetermined block (step 40
5) Perform drawing processing. The contents of the drawing process by the CPU 113 are the same as those of the drawing accelerator 115. The CPU 113 performs a color conversion process, a BG / UCR process, a γ conversion process, a scaling process, and a halftone process (steps 406 to 410). The result is stored in the CPU drawing result temporary holding area 202 of the memory 112 (step 411). Also in the CPU 113,
The drawing process need not be in this order. The CPU 113
Each time a predetermined block is processed, the drawing accelerator 11
5 is a processing status holding area indicating how far the processing has been performed
Referring to FIG. 05 (step 403), the area where the CPU 113 has processed the drawing command and the drawing accelerator 115
Is checked whether or not the sum with the area processed by the drawing command is equal to the processing target area of the drawing command, that is, whether the drawing processing for the object of the drawing command has been completed (step 404). If not complete,
The CPU 113 starts similar rendering processing for the next predetermined block from the end of the processing target area.

In this manner, when the sum of the area processed by the drawing command by the CPU 113 and the area processed by the drawing command by the drawing accelerator 115 becomes equal to the processing target area of the drawing command, the CPU 113 sends a command to the drawing accelerator 115. Command to stop the drawing process (step 412). Then, the CPU 113
The drawing results stored in the CPU drawing result temporary holding area 202 and the drawing accelerator drawing result temporary holding area 203 are compared with the current information in the output information storage area 204 by ROP.
By superimposing (step 413), the information in the output information storage area 204 is updated.

Thereafter, the CPU 113 checks whether or not there is a drawing command to be processed next in the output command stored in the output command storage area 201 of the memory 112, and if so, extracts the drawing command and sends it to the drawing accelerator 115. It issues a processing command and performs the drawing processing itself. Then, when there is no drawing command to be processed next, the process for the output command ends.

In the above description, the drawing accelerator 115
Performs processing for all drawing commands, but processing may be performed depending on conditions such as that the drawing accelerator 115 performs processing for only some of the commands, or that processing is performed only when the object has a certain size or more. There may be cases where it is performed and cases where it is not performed.

In the above description, the decompression process is not performed by the CPU 113 or the drawing accelerator 115. However, for example, when a compression method for independently compressing each block is used, the host I / F 111 performs the decompression process. In the absence state, the CPU 113 and the drawing accelerator 115 may also perform decompression processing.

Further, in the above description, the ROP processing is performed by the CP
U113 is performed after the sum of the area processed by the drawing command and the area processed by the drawing accelerator 115 is equal to the processing target area of the drawing command.
Sequentially ROs the area where the rendering command has been processed.
P processing may be performed.

FIGS. 5 and 6 are diagrams showing specific images of the drawing process. Now, it is assumed that the instruction order of a certain page of the output instruction is as shown in FIG. ROPCC and R
OP88 is an instruction for defining ROP processing. Here, ROPCC (SRCCOPY) is an overwrite mode,
OP88 (SRCAND) defines the logical product mode. FIG. 5B shows a drawing image of each of the drawing commands A, B, and C, and FIG. 5C shows the positions of these drawing images on the output information storage area (bitmap).

First, the CPU 113 and the drawing accelerator 115 perform drawing processing of the drawing instruction A in parallel from the end side and the top side of the processing target area, and the sum of the areas processed in both processing areas is equal to the processing target area of the drawing instruction A. When it becomes, CPU11
3 superimposes the processing result of the drawing command A on the current information in the output information storage area (bit mat) by ROP processing, and updates the information in the output information storage area. In this example, the ROP mode when processing the drawing command A is SRCCOPY
If the current information in the output information storage area is empty (the background is all white), the output information storage area becomes as shown in FIG.

Next, the CPU 113 and the drawing accelerator 115 similarly perform drawing processing of the drawing command B in parallel from the end side and the top side of the processing target area.
The PU 113 superimposes the processing result of the drawing command B on the current information of the output command storage area by ROP processing, and updates the information of the output command storage area. In this example, since the POP mode for processing the drawing command B is still SRCCOPY, after the processing of the drawing command B, the output command storage area is in FIG.
(B).

Next, the CPU 113 and the drawing accelerator 115 similarly draw the drawing command C in parallel from the end side and the head side of the processing target area, and when the processing is completed, the CPU 113 executes the processing result of the drawing command C. And ROP
The information of the output instruction storage area is updated by the processing. In this example, the ROP mode when processing the drawing command C is from SRCCOPY to SRCAND (logical product mode).
After the processing of the drawing command C, the output command storage area becomes as shown in FIG.

The output command sent from the host computer 10 to the printer 100 generally includes text data (character code data). This text data is converted into a dot pattern by the CPU 113 and developed in the output command storage area. Since the processing of the text data is not the object of the present invention, its details are omitted.

FIG. 7 is an example of another processing flow of the drawing processing in this embodiment. This is because a drawing process function (a kind of subroutine) is prepared in the CPU 113 and the CPU 113
The drawing process at 113 is assigned to the drawing process. Hereinafter, FIG. 7 will be described focusing on differences from the processing flow of FIG.

The CPU 113 extracts a drawing command from the output commands stored in the output command storage area 201 of the memory 112 (step 701). Next, the drawing accelerator 1
It is determined whether or not No. 15 is in the drawing process (step 70).
2) If not being processed, a processing command is issued to the drawing accelerator 115 to process one unprocessed block closest to the head of the processing target area of the drawing command (step 703). Next, it is confirmed whether or not the drawing process in the CPU 113 is in the process of drawing (step 704). If not, the unprocessed one block closest to the end of the processing target area of the drawing command, for example, is checked. To handle C
Command the drawing process in PU 113 (step 70)
5).

The drawing accelerator 115 is connected to the CPU 11
3 (step 721), a predetermined block of the object of the drawing command specified by the processing command is read from the output command storage area 201 of the memory 112 (step 722), and as described with reference to FIG. Then, a color conversion process, a BG / UCR process, a γ conversion process, a scaling process, and a halftone process are performed (step 723).
12 drawing accelerator drawing result temporary holding areas 203
(Step 724). Then, the drawing accelerator 115 issues a drawing processing end notification to the CPU 113 by interruption or the like (step 725),
It waits for the next processing instruction from the PU 113.

Similarly, the drawing process of the CPU 113
When a processing instruction is received from the PU 113 (step 73)
1) Reading a predetermined block of the object of the drawing command specified by the processing command from the output command storage area 201 of the memory 112 (step 732), color conversion processing, BG / UCR processing, γ conversion processing, scaling Processing and halftone processing (step 733).
The processing result is stored in the drawing result temporary holding area 202 (step 734). Then, a drawing process end notification is issued to the CPU 113 (step 735).

Hereinafter, the CPU 113 determines whether or not the sum of the area processed by the drawing command by the drawing process in the CPU 113 and the area processed by the drawing command by the drawing accelerator 115 becomes equal to the processing target area of the drawing command.
Drawing process in U113 and drawing accelerator 115
And the drawing process is repeatedly executed, and when they are equal, that is, when the drawing process of the drawing command is completed (step 706), the drawing process of the CPU 113 and the drawing accelerator 115 are stopped. (Step 707,
708). Upon receiving the drawing process stop command, the drawing process and the drawing accelerator 115 in the CPU 113 stop the drawing process and wait for a new command.

The CPU 113 controls the drawing accelerator 11
5 after issuing a stop command to the drawing process,
The drawing results stored in the CPU drawing result storage area 202 and the drawing accelerator drawing result temporary holding area 203 are compared with the current information in the output information storage area 204 by RO.
The P information is superimposed (step 709), and the information in the output information storage area 204 is updated (step 71).
0). Thereafter, the CPU 113 checks whether or not there is a drawing command to be processed next in the output command stored in the output command storage area 201 of the memory 112, and if so, extracts the drawing command and repeats the drawing process. Will be.

In FIG. 7, the drawing process in the CPU 113 is generated every time the CPU issues a drawing command, and is deleted when the drawing process is completed or when a drawing stop command is received. You may. Also,
Also in this embodiment, when the block of the processing target area is divided so that decompression can be performed independently for each block, the CPU
The drawing process in 113 and the drawing accelerator 115 may perform decompression processing for each block.

FIG. 8 is an example of still another processing flow of the drawing processing in the present embodiment.
15 shows a processing flow. This is because, when the drawing accelerator 115 is provided with a means for storing the result of the drawing processing performed by the drawing accelerator 115 (drawing accelerator drawing result temporary holding means), the drawing accelerator 115 stores the result in the drawing result temporary holding means. When the information exceeds the threshold value, the information is copied to the CPU drawing result temporary holding area 202 in the memory 112. Other than this, it is basically the same as FIG. 4 and FIG. Here, the description will focus on the differences from FIG.

When the drawing accelerator 115 receives a processing command from the CPU 113 (step 801), as shown in FIG. 4, the drawing accelerator 115 stores the object (image data) of the drawing command from the output command storage area 201 of the memory 112. A predetermined block is read (step 802), color conversion processing, BG / UCR processing, γ conversion processing, scaling processing,
Halftone processing is performed (step 803), and the processing result is stored in the self-drawing result temporary holding unit in the drawing accelerator 115 (step 804). Although omitted in FIG. 8, the CPU 113 (or the drawing process of the CPU 113) similarly stores the output command storage area 201 of the memory 112.
, A predetermined block is read, color conversion processing, BG / U
Perform CR processing, γ conversion processing, scaling processing, halftone processing,
The processing result is stored in the CPU drawing result temporary holding area 202 of the memory 112.

Next, the drawing accelerator 115 checks whether the information (image data) stored in the self-drawing result temporary holding means exceeds the threshold (step 80).
5) If it exceeds, copy it to the CPU drawing result temporary holding area 203 of the memory 2 and invalidate the information stored in the own drawing result temporary holding means (step 80).
6).

The threshold value is set, for example, as follows. “Threshold” = “size of temporary storage area of drawing result” − “information amount of processing target area of one block”

According to this embodiment, even if the storage capacity of the drawing result temporary holding means provided in the drawing accelerator 115 is not sufficiently large, the drawing processing result by the drawing accelerator 115 can be written at a high speed, and the cost can be reduced. A simple drawing result temporary holding means can be used. Also, by determining the size of the block based on the size (capacity) of the drawing result temporary holding means, the information stored in the drawing result temporary holding means exceeds the threshold value and is copied to the CPU drawing result temporary holding area. You can control the number of times you do.

The main functions and effects of the first embodiment will be listed below. (1) A printer as an image output device has a CPU as a first processing unit and a drawing accelerator as a second processing unit. The CPU interprets a drawing command from a host computer and sends a drawing target area to the drawing accelerator. For example, by causing the CPU to perform drawing processing from the end block, for example, from the end block, the CPU can also perform drawing processing from the processing target area. provide.

(2) The drawing processing includes at least one of decompression processing, color conversion processing, BG processing, UCR processing, γ conversion processing, scaling processing, and halftone processing. In the case of (1), there is provided an image output apparatus capable of easily parallelizing time-consuming drawing processing and performing high-speed drawing processing.

(3) The CPU performs drawing processing by software, and the drawing accelerator performs drawing processing by hardware, thereby providing an image output apparatus capable of performing drawing processing at high speed without changing the configuration of the CPU.

(4) By providing an area for storing the result of the drawing processing by the drawing accelerator outside the drawing accelerator such as the memory 112, the structure of the drawing accelerator can be simplified, and the drawing processing can be performed at low cost and at high speed. An image output device is provided.

(5) By providing an area for storing the result of the drawing processing by the drawing accelerator in the drawing accelerator, the drawing accelerator can write the result of the drawing processing by itself at high speed. And an image output device capable of performing a drawing process.

(6) When the information stored in the drawing processing result storage area in the drawing accelerator exceeds the threshold, the memory 1
12, the drawing accelerator can write the result of its own drawing processing at high speed even if the information storage area in the drawing accelerator is not sufficiently large. An image output device capable of performing the above is provided.

(7) Since the drawing accelerator has processing status holding means indicating the extent to which the drawing process instructed by the CPU has been performed, the CPU can easily grasp the drawing process status of the drawing accelerator and perform the drawing process at high speed. An image output device capable of performing the above is provided.

(8) When the CPU determines that the sum of the area where the CPU has completed the drawing processing and the area where the drawing accelerator has completed the drawing processing has become equal to the processing target area of the drawing command, the CPU stops the processing. By issuing a command and terminating the process of the drawing command, it is possible to reliably perform the drawing process of the drawing command, and to provide an image output device capable of performing the drawing process at high speed without any problem.

[Second Embodiment] In the first embodiment, a printer as an image output device is provided with a drawing accelerator integrally. However, in this embodiment, one or a plurality of printers as image output devices and a drawing accelerator are used. The accelerators are intended for printer systems (image output systems) each connected to a network such as a LAN.

FIG. 9 shows a block diagram of a basic configuration example of the present embodiment. In the figure, a printer 9 as an image processing device
Reference numeral 10 is connected to a host computer 900 as an upper information processing apparatus via a network 930, and similarly to a drawing accelerator 920 via the network 930. The printer 910 includes a host / drawing accelerator I / F 911, a CPU 912, a memory 913, a print engine I / F 914, a print engine 915, and the like. The printer 910
Corresponds to the drawing accelerator 11 from the printer 100 in FIG.
5 is basically the same as that of FIG. However, the host / drawing accelerator I / F 911 is provided between the printer 910 and the computer 900 and the printer 91.
Responsible for both interface control between 0 and the drawing accelerator 920. The memory 913 also has basically the same configuration as that of FIG. 2, but in the present embodiment, the processing status holding area 205 of FIG. 2 is unnecessary.

The drawing accelerator 920 preferably performs drawing processing by hardware as shown in FIG. 3 in order to perform drawing processing at high speed. However, the drawing accelerator 920 is configured to perform drawing processing by software or the like. There may be. Conversely, the CPU 912 is preferably configured to perform the drawing process by software, but may be configured to perform the drawing process by hardware. These are the same as in the first embodiment.

The operation outline of FIG. 9 will be described below. Here, it is assumed that the CPU 912 loads a program and the like necessary for the drawing process from the memory 913 and fetches necessary parameters and the like. Similarly, in the drawing accelerator 920, it is assumed that necessary parameters are fetched from the memory 913 of the printer 900 via the network 930 and set in each processing unit. Note that the computer 900 may directly transmit parameters to the drawing accelerator 920 via the network 930.

The computer 900 creates a drawing command based on a command from a user or the like, and sends an output command to the printer 910 to draw and output an image based on the drawing command. The output command generally includes a control command and a plurality of drawing commands. The host / drawing accelerator I / F 911 in the printer 910 writes an output command received from the computer 900 to the memory 913. In the host / drawing accelerator I / F 911, if the output command sent from the host computer 900 is compressed, it is decompressed and written to the memory 913. This is the same as in the first embodiment.

The CPU 912 takes out the control command from the output command written in the memory 913, and sequentially
Fetch the drawing instruction to be processed. Here, the CPU 912
The process of extracting the drawing commands sequentially from the output commands written in the memory 913 is performed by the host / drawing accelerator I /
The process can be performed at a high speed by starting before the process of writing the output command received from the computer 900 by the F911 into the memory 903 is completed. This is also the same as in the first embodiment.

The CPU 912 interprets the drawing command fetched from the memory 913 and reads the host / drawing accelerator I
/ F 911 to input a processing instruction to the drawing accelerator 92
Send to 0. Drawing accelerator 920 receiving the processing instruction
Performs drawing processing of the drawing command, and stores a drawing processing result in a drawing accelerator drawing result temporary holding area. At the same time, the CPU 912 also performs drawing processing for the drawing command, and stores the drawing processing result in the CPU drawing result temporary holding area. As described in the first embodiment, it is preferable that the drawing accelerator temporary storage area and the CPU temporary storage area are secured in the memory 913 of the printer 910. May be secured in the drawing accelerator 920. Thereby, the load on the host / drawing accelerator I / F 911 can be reduced. Further, the CPU 912 may interpret the drawing command and transfer a processing command to which the object of the drawing command is added to the drawing accelerator 920.

Here, the CPU 912 has its own CPU 912.
If the rendering process is completed earlier than the rendering accelerator 920, the CP
The contents of the U drawing result temporary holding area and the contents (background) of the output information storage area are overlapped by ROP processing. on the other hand,
If the drawing accelerator 920 finishes the drawing processing earlier than the own CPU 912, the drawing accelerator 920
The contents of the drawing accelerator temporary storage area and the contents of the output information storage area, which are the drawing processing results of
Overlap by processing.

Hereinafter, similarly, the drawing process of the drawing command is sequentially repeated. Then, at a point in time when a specific instruction is processed, the print engine I / F 914 outputs the processing result (print data) of the output instruction stored in the output information storage area of the memory 913 to the print engine 915.
Send to The print engine 915 prints based on the processing result of the output command received from the print engine I / F 914.

FIG. 10 shows a processing flow example of the drawing processing of the present embodiment. FIG. 10 shows a processing flow for one drawing command, which is repeated for each drawing command included in the output command.

The CPU 912 takes out the drawing command from the memory 913 (step 1001), and instructs the drawing accelerator 920 to process the drawing command (step 1002). After that, the CPU 912 performs a drawing process for the drawing command, and stores the processing result in the CPU drawing result temporary holding area (steps 1003 to 1003).
8). When the drawing accelerator 920 also receives a processing command from the CPU 912 (step 1021), it performs a drawing process for the drawing command and stores the processing result in the drawing accelerator drawing result temporary holding area (step 10).
22-1027).

Here, the drawing process in the CPU 912 is performed as follows. The CPU 912 reads the object of the drawing command stored in the memory 912, and first converts the object in the RGB format into a computer so that the computer 900 and the printer 910 can visually obtain the same output.
A color conversion process for converting the object into an MY format object is performed (step 1003). Next, black plate generation and under color removal are performed by BG / UCR processing, and the CMY format object is
Convert to MYK format object (step 100
4). Next, gamma conversion processing is performed to convert the density of each CMYK plate so that the object has density characteristics suitable for the printer 910 (step 1005). Next, if necessary, a scaling process is performed to convert the object into an appropriate size (step 1006). Next, halftone processing is performed to convert the object into a color depth suitable for the print engine 915 (step 1007).
Then, the result of processing the drawing command is stored in the CPU drawing result temporary holding area (step 1008). Here also, the drawing process need not be in this order.

The drawing processing by the drawing accelerator 920 is similarly performed as follows. Drawing accelerator 920
Accesses the printer 900, reads the object of the drawing instruction stored in the memory 913 via the host / drawing accelerator I / F 911, and performs color conversion processing, BG / UCR processing, and γ conversion processing (step 1022). If necessary, a scaling process is performed (step 1025), a halftone process is performed (step 1026), and the processing result is stored in a drawing accelerator drawing result temporary holding unit (step 1027).

In the temporary storage area for CPU drawing results and the temporary storage area for drawing accelerators, the drawing command is not stored after the drawing process is completed, but is stored in the temporary storage area.
A method may be used in which the image data is stored at the time when the drawing processing for a specified area such as a line is completed, and the drawing processing and the storage are sequentially performed. Also, as described in the first embodiment, the processing target area may be divided into blocks so that expansion can be performed independently for each block, and expansion processing may be performed by the CPU 912 and the drawing accelerator 920.

When the CPU 912 finishes the drawing process earlier than the drawing accelerator 920 (this occurs, for example, when the network is under a heavy load), the CPU 912 sends a CPU drawing end notification to the drawing accelerator 920 (step 1009). Upon receiving the CPU drawing end notification, the drawing accelerator 920 suspends the drawing process at that time and invalidates the drawing result in the drawing accelerator drawing result temporary holding area (step 1030). Conversely, when the drawing accelerator 920 finishes the drawing processing earlier than the CPU 912, the drawing accelerator 920 sends a drawing accelerator drawing end notification to the CPU 912 (step 1029). CP
Upon receiving the drawing accelerator drawing end notification, U912 suspends the drawing process at that point and invalidates the drawing result in the CPU drawing result temporary holding area (step 101).
2).

Thereafter, the CPU 912 performs the ROP process using the effective drawing result in the CPU drawing result temporary holding area and the drawing accelerator drawing result temporary holding area, and outputs the drawing result of the drawing command to the output information. It is stored in the storage area (step 1011). And the CPU 91
2 checks whether there is a drawing command to be processed next among the output commands stored in the memory 913, and if so, extracts the drawing command and repeats the drawing process in the same manner.

Next, another embodiment of an image output system (printer system) in which one drawing accelerator is shared by a plurality of printers as image output devices will be described.

FIG. 11 shows an example of the present image output system. In the figure, a computer 111 as an information processing device
0, 1120, a printer 1130 as an image output device,
1140 and a drawing accelerator 1150 are connected via a network 1160. The computers 1110 and 1120 generate a drawing command based on a command from a user (not shown) or the like, and
An output command is sent to any one of 40 to draw and output an image based on the drawing command. Printer 1130, 1
140 performs the drawing processing by itself and, if the drawing accelerator 1150 is available, performs the drawing processing by using the drawing accelerator 1150.

FIG. 12 shows a configuration example of the drawing accelerator 1150. The network I / F 1151 is an interface control circuit with the network 1160. The control unit 1152 controls the operation of the network I / F 1151, the drawing processing unit 1153, the drawing accelerator prediction processing time calculation unit 1154, and the like. The control unit 115
2 can access the memories of the printers 1130 and 1140 via the network I / F 1151. The drawing processing unit 1153 is a general term for the color conversion processing unit, the BG / UCR unit, the γ conversion processing unit, the scaling processing unit, the halftone processing unit, and the like shown in FIG. The drawing accelerator prediction processing time calculation unit 1154 is a calculation unit that predicts the time until the drawing accelerator finishes the drawing processing being processed. The processing time required for drawing can be predicted from, for example, input / output data, data transfer speed, drawing processing speed, and the like. The drawing accelerator prediction processing time calculation unit 1154
The control unit 1152 calculates the estimated processing time obtained by the printer 1130 and 114 via the network I / F 1151.
By sending it to 0, the CPU of the printer can know how long the drawing accelerator 1150 needs to wait.

FIG. 13 shows a schematic processing flow example of the printers 1130 and 1140 of the image output system of FIG.
Hereinafter, a description will be given with reference to FIG. 13 particularly focusing on differences from FIG.

Now, it is assumed that the computer 1110 creates a drawing command based on a command from a user (not shown) or the like and sends an output command to the printer 1130 to draw and output an image based on the drawing command. Printer 11
30 sequentially interprets the rendering command and, if the rendering accelerator 1150 is available, causes the rendering accelerator 1150 to perform the rendering process for the rendering command, and the printer 1130 also performs the rendering process for the rendering command (step 1301-1306). The operation when the drawing accelerator 1150 cannot be used is the same as the operation when the printer 1140 described later cannot use the drawing accelerator 1150.

Upon receiving a drawing command from the printer 1130, the drawing accelerator 1150, under the control of the control unit 1152, calculates the drawing accelerator prediction processing time 1154.
In, the processing time required for drawing by the drawing accelerator 1150 is predicted from the input / output data, the data transfer speed, and the drawing processing speed. For example, if the input data amount is 0.1
When the MB, the output data amount is 0.4 MB, the data transfer speed is 10 MB per second for both input and output, and the drawing processing speed is 50 MB per second, 0.01 seconds for data input and 0.04 seconds for data output.
Seconds and 0.01 seconds are required for drawing processing, and a total of 0.06 seconds is set as a predicted processing time. Then, the drawing processing unit 1153 proceeds with the processing of the drawing command. When a predetermined amount of drawing processing is performed, for example, at the time when the drawing processing of one line is completed, the drawing accelerator prediction processing time calculation unit 1154 executes the prediction processing. Recalculate the time and update the estimated processing time.

While the printer 1130 is using the drawing accelerator 1150, the computer 1120 creates a drawing command based on a command from a user (not shown) or the like, and sends the drawing command to the printer 1140. Suppose that an output command has been sent to draw and output an image. Similarly to the printer 1130, the printer 1140 attempts to perform drawing processing using the drawing accelerator 1150. However, it is assumed that the drawing accelerator 1150 is used by the printer 1130 and cannot be used by the printer 1140.

Therefore, the printer 1140 sends the drawing accelerator 11150 calculated by the drawing accelerator prediction processing time calculation unit 1154 from the drawing accelerator 1150.
The current estimated processing time 50 is obtained, and it is known how long it is necessary to wait for the drawing accelerator 1150 (step 1301). In addition, the printer 1140 uses the same method as the case where the drawing accelerator prediction processing time calculation unit 1154 predicts the processing time.
Calculates the time required to perform the processing of the drawing command (step 1302). If the drawing accelerator prediction processing time is longer than the printer prediction processing time, the printer 1140 transmits the drawing command to the drawing accelerator 1
Process without using 150 (steps 1303, 130
9). Conversely, if the drawing accelerator prediction processing time is shorter than the printer prediction processing time, the printer 1140
While the drawing command is being processed by the printer 1140, it is checked whether the drawing accelerator 1150 is available at appropriate intervals.
A command is issued to the drawing accelerator 1150 to process the drawing command (steps 1303 to 1308).

Here, an output command is sent from the computer 1110 to the printer 1130, and
In the case where the output command is also sent from the printer 120 to the printer 1140, the operation of the image output system when the printers 1130 and 1140 perform the drawing process at the same time has been described. When an output command is sent to the printer 1140 from the same computer 1110, the same operation can be performed using the drawing accelerator 1150.

Further, for example, if the drawing accelerator 1150 is included in the printer 1130 and the other printer 1
The same operation can be performed even in a configuration using the drawing accelerator 1150 from 140.

The network 1160 is not general, and may have a unique structure. For example, a network generally used and widely used, for example, 100Base
With e-TX, an image output system can be constructed at low cost. A drawing command flows from the printers 1130 and 1140 to the drawing accelerator 1150, and a drawing processing result flows from the drawing accelerator 1150 to the printers 1130 and 1140. Therefore, the drawing accelerator 115
In order to effectively use the high speed of network 0, network 1
It is preferable that 160 is capable of high-speed transfer as much as possible, for example, 1000Base-T or more is optimal.

Further, as shown in FIG.
30 and 1140 and the drawing accelerator 1050 are connected to the switching hub 1400 functioning as a bridge, so that data exchange between the printers 1130 and 1140 and the drawing accelerator 1150 can be performed on the network 1.
The effect on other devices connected to 160 can be reduced.

The main functions and effects of the second embodiment will be listed below. (1) Make the drawing accelerator perform drawing processing, and
A printer, which is an image output device, performs the same drawing process, and provides an image output system that can perform a drawing process at a high speed by reflecting a processing result of a printer and a drawing accelerator that has finished processing earlier.

(2) Even if the drawing accelerator can perform high-speed processing, transmission of the processing result from the drawing accelerator to the printer may be delayed depending on the state of the network and the like. In this case, the processing result in the printer is reflected. Therefore, an image output system that requires a minimum reduction in processing speed is provided.

(3) If the drawing accelerator finishes the drawing process earlier than the printer, the drawing process of the printer is interrupted and the result of the drawing process of the printer is discarded. provide.

(4) When the printer finishes the drawing processing earlier than the drawing accelerator, the drawing processing of the drawing accelerator is interrupted, and the drawing processing result of the drawing accelerator is discarded. Provide an output system.

(5) By making the drawing accelerator available from a plurality of printers as image output devices, an image output system using the drawing accelerator is provided at low cost.

(6) Since the drawing accelerator calculates the predicted processing time for predicting the time until the drawing processing in progress is completed and can present it to the printer, the printer can use the drawing accelerator more efficiently. Provide an output system.

In the embodiments of the present invention, the image output device has been described as a printer. However, the present invention is not limited to the printer, but may be a CAD or computer graphics (C).
G), a presentation, and various other devices and systems that perform drawing processing and output as necessary.

[0099]

As described above, according to the present invention,
It is possible to provide an image output method, an image output device, and an image output system capable of performing drawing processing easily and at high speed. Further, when the image output device and the drawing accelerator are connected by a network, it is possible to provide an image output system capable of performing a high-speed drawing process even when the network is under a heavy load.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration example of an image output device according to the present invention.

FIG. 2 is a diagram illustrating a configuration example of a memory in the image output device.

FIG. 3 is a diagram illustrating a configuration example of a drawing accelerator.

FIG. 4 is a flowchart example of a drawing process in FIG. 1;

FIG. 5 is a diagram illustrating a specific example of a drawing process.

FIG. 6 is a diagram illustrating a specific example of a drawing process.

FIG. 7 is another flowchart example of the drawing process in FIG. 1;

FIG. 8 is a further flowchart example of the drawing process in FIG. 1;

FIG. 9 is a block diagram illustrating a basic configuration example of an image output system according to the present invention.

FIG. 10 is a flowchart example of a drawing process in FIG. 9;

FIG. 11 is a schematic block diagram showing another configuration example of the image output system according to the present invention.

12 is a diagram illustrating a configuration example of a drawing accelerator in FIG. 11;

FIG. 13 is a schematic flowchart example of a drawing process in FIG. 11;

FIG. 14 is a schematic block diagram showing another configuration example of the image system according to the present invention.

[Explanation of symbols]

 Reference Signs List 10 host computer (information processing device) 100 printer (image output device) 110 printer controller 113 CPU in printer 114 memory in printer 115 drawing accelerator in printer 120 print engine 201 output command storage area 202 CPU drawing result temporary holding area 203 drawing accelerator drawing Result temporary storage area 204 Output information storage area 205 Processing status storage area 311 Color conversion processing section 312 BG / UCR processing section 313 γ conversion processing section 314 Magnification processing section 315 Halftone processing section 900 Host computer 910 Printer 920 Drawing accelerator 930 Network 1110, 1120 Computer 1130, 1140 Printer 1150 Drawing accelerator 1160 Network

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasunori Ota 1-3-6 Nakamagome, Ota-ku, Tokyo F-term in Ricoh Co., Ltd. (Reference) 2C087 AB05 BA03 BC05 5B021 AA01 BB01 BB04 CC05 5B057 AA01 CA01 CA08 CB01 CB08 CC01 CD05 CE11 CE17 CH01 CH11 5C076 AA01 AA21 AA22 AA26 AA27 AA36 BA02 BA06

Claims (21)

[Claims] 1. An image output method for interpreting a drawing command, performing a drawing process, and outputting the processed image, wherein a drawing process is performed by performing a drawing process on a processing target area of the drawing command in parallel from a start side and an end side. An image output method characterized by outputting a result. 2. The image output method according to claim 1, wherein
An image characterized by terminating the processing of the drawing command when the sum of the area where the drawing processing is completed from the top side and the area where the drawing processing is completed from the end side becomes equal to the processing target area of the drawing command. output method. 3. An image output method for interpreting a drawing command, performing a drawing process, and outputting the processed image. An image output method, comprising: outputting a result of a rendering process. 4. The image output method according to claim 1, wherein the processing target area of the drawing command is divided into a plurality of blocks, and the drawing processing is performed in block units. 5. The image output method according to claim 1, wherein the drawing processing includes decompression processing, color conversion processing, BG / UCR.
An image output method, which is at least part or all of processing, gamma conversion, scaling, and halftone processing. 6. Based on an output command from an information processing device,
An image output device that interprets and outputs a drawing command, wherein the image output device has a first processing unit and a second processing unit that can operate independently of the first processing unit. The first processing means interprets the drawing command, sends a processing command to the second processing means, and performs a drawing process on the processing target area of the drawing command from the top or end side, An image output device, wherein the processing means receives the processing command from the first processing means, and performs a drawing process on a processing target area of the drawing command from a side opposite to the first processing means. . 7. The image output device according to claim 6, wherein
An image output apparatus, wherein a processing target area of a drawing command is divided into a plurality of blocks, and the first processing means and the second processing means perform the drawing processing in block units, respectively. 8. The image output device according to claim 7, wherein
The first processing means sends a processing command to the second processing means in block units, and the second processing means performs processing on the first processing means every time the drawing processing of the block is completed. An image output device for sending an end notification. 9. The image output device according to claim 6, wherein said first processing means performs drawing processing by software, and said second processing means performs drawing processing by hardware. Image output device. 10. The image output device according to claim 6, wherein the means for storing the result of the drawing processing performed by the second processing means is provided outside the second processing means. Image output device. 11. The image output apparatus according to claim 6, wherein a means for storing a result of the drawing processing performed by said second processing means is provided in said second processing means. Image output device. 12. The image output device according to claim 11, wherein the second processing means is configured to: when information stored in a means for storing a result of the drawing processing in the second processing means exceeds a threshold value; An image output apparatus, wherein the information is copied in the first processing means. 13. The image output apparatus according to claim 6, further comprising: a processing status holding unit that indicates the extent to which the second processing unit has performed the drawing processing, wherein the first processing unit includes the processing unit. Based on the information of the status holding means, it was determined that the sum of the area where the first processing means completed the drawing processing and the area where the second processing means completed the drawing processing became equal to the processing target area of the drawing instruction. An image output device that ends the drawing process. 14. An image output system comprising an image output device and a drawing accelerator for performing a drawing process independently of the image output device, wherein the image output device performs drawing based on an output command from an information processing device. It interprets the command, sends a processing command to the drawing accelerator, and performs a drawing process of the drawing command. The drawing accelerator receives a processing command from the image output device, and performs a drawing process of the drawing command on the image. An image output system, which is performed in parallel with an output device, wherein the image output device reflects a processing result of one of the image output device and the drawing accelerator that has been processed earlier. 15. The image output system according to claim 14, wherein said image output device sends a drawing end notification to said drawing accelerator when drawing processing is completed by said image output device, and said drawing accelerator outputs said drawing accelerator. Sending a drawing end notification to the image output device when the drawing process is completed. 16. The image output system according to claim 15, wherein when the drawing accelerator finishes the drawing process earlier, the image output device interrupts the drawing process of the image output device, and When the image output device finishes the drawing process early, the drawing accelerator interrupts the drawing process of the drawing accelerator and discards the drawing process result of the drawing accelerator. Image output system. 17. The image output system according to claim 14, wherein said drawing accelerator can be used from a plurality of image output devices. 18. The image output system according to claim 14, wherein said drawing accelerator has a prediction processing time calculation unit for predicting a time until a drawing process being processed by said drawing accelerator is completed, The image output device acquires a prediction processing time of the drawing accelerator, and prevents the drawing accelerator from performing a drawing process when the prediction processing time satisfies a certain condition. system. 19. The image output system according to claim 14, wherein said image output device performs drawing processing by software, and said drawing accelerator performs drawing processing by hardware. 20. The image output system according to claim 14, wherein the information processing device, the image output device, and the drawing accelerator are connected on the same network. 21. The image output system according to claim 14, wherein the image output device and the drawing accelerator are connected via a switching hub to a network to which the information processing device is connected. .