JPH09204278A - Printing system and print processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit image data to a printer without inviting the decline of throughput and the delay of FCOT (time until a first page is printed and outputted) by making respective processors judge whether to transmit the image data by a file unit or to transmit them by a page unit beforehand in the case that the plural processors for decoding a PDL(page description language) are connected through a shared line to the printer. SOLUTION: When an FEP(front end processor) 12 receives a printing job described in the PDL transmitted from clients 10a-10d, a printing data processing part 12a performs the preprocessing of the printing job and the decoding and compressing processing of the first page, a transmission time prediction part 12d predicts transmission time in the case of performing job unit transmission and in the case of performing page unit transmission based on the result data and a transmission unit selection part 12e instructs whether to perform the job unit transmission or the page unit transmission to an image data output part 12b based on the predicted result.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, when a processing device interposed between a client and a printing device receives a print job from the client, should send image data in advance in file units or in page units. The present invention relates to a printing system and a print processing method for determining image quality and transmitting image data to a printing device without lowering throughput and delaying FCOT.

[0002]

2. Description of the Related Art Conventionally, a page description language (Page Descripti
on Language: Hereinafter referred to as "PDL". The print job including the print data described in (1) is transmitted to the front end processor (hereinafter referred to as “FEP”), and the FEP prints the print data using the printing device while sequentially decoding (decomposing) the print data. Techniques for processing are known.

[0003] For example, DocuTech Network Model 135 developed by Fuji Xerox as a network publishing system.
In 5), FEP (DocuTech Network Service-J) is P
When print data described in DL is received, the print data is decoded page by page to create image data, and the image data is compressed and output to a high-speed digital copying machine (DocuTech ProductionPublisher 135). Has been done.

In the printing system represented by the Docutech network model 135, the time for the printing apparatus to print out the image data is usually shorter than the time for the FEP to decode the printing data. Often introduces a system configuration in which a printer is shared to improve throughput.

For example, in the above-mentioned Dotechc network model 135, a plurality of FEPs are connected to a high-speed digital copying machine by using a shared line, and when each FEP finishes decoding the first page, the shared line is If it is empty, image data transmission in page units (hereinafter referred to as "page unit transmission") is started. When a certain FEP starts page-by-page transmission to the high-speed digital copying machine, the shared line is occupied until all pages are received by the high-speed digital copying machine.

If the shared line is not idle at the time when each FEP finishes decoding the first page, etc., the image after the second line and subsequent pages are decrypted and the shared line becomes idle Start sending data.

FIG. 6 is a diagram showing a time chart in the network publishing system.

As shown in FIG. 6 (a), when the FEP 1 finishes decoding the first page, etc., it checks whether the shared line is idle before performing the second page decoding process. If the common line is idle, the image data obtained by decoding the first page is transmitted to the high speed digital copying machine. After that, each time the decoding of each page is completed, the decoded page image is sequentially transmitted to the high speed digital copying machine.

Therefore, during the period from the transmission start time of the first page to the transmission end time of the last page, the FEP 1 occupies the common line.

Even if another FEP2 decodes the first page of the print data during the monopolization of the common line by the FEP1, the FEP2 continues to be occupied because the common line is occupied at this point. Then, decoding of subsequent pages is continued, and when the common line becomes idle, the image data is sequentially transmitted to the high speed digital copying machine.

As described above, the conventional technique represented by this network publishing system is configured to sequentially transmit the processed image data to the printing apparatus in page units.

However, when page-based transmission is performed as in this prior art, the common line is occupied until the transmission of the final page is completed, which causes a problem that the throughput of the entire system decreases.

Therefore, by using the job unit transmission technique of storing image data until all pages of the print job are decoded and transmitting the image data in units of jobs when decoding of all pages is completed, It is possible to avoid such a decrease in throughput.

[0014]

However, if the image data is fixedly transmitted in units of jobs, the time until the first page is printed out by the printing device (hereinafter referred to as "FCOT") is delayed. Will be done.

For example, as shown in FIG. 6B, when it takes time to transmit the image data obtained by decoding the print data, when the image data is transmitted in file units and in page units There is no big difference in time. Nevertheless, if the image data is to be transmitted on a job-by-job basis, FCOT will be significantly delayed.

Therefore, in order to make the FCOT and the throughput compatible with each other, when the image data decoded by the FEP is transmitted to the printing apparatus, it is transmitted in page units or in file units in consideration of the characteristics of the print data. It is necessary to use differently.

Specifically, if it is possible to obviously reduce the exclusive time of the shared line by transmitting the image data in units of jobs, the image data should be transmitted in units of jobs, and the image data is transmitted in units of pages. If there is no great difference in the time required between the case of sending by (1) and the case of sending by job, it should be sent by page.

However, in order to determine whether to transmit the image data in page units or in job units before actually transmitting the image data, the time required for transmitting the image data in file units and It is necessary to estimate the required transmission time when transmitting image data in page units.

Therefore, when the FEP decodes the print data described in PDL, how is the required transmission time when the image data is transmitted in file units and the required transmission time when the image data is transmitted in page units? Estimating is an important issue.

Particularly, the print data described in PDL is P
Since there is no correlation between the data size of the DL file and the data size of the image data obtained by interpreting the PDL, it is difficult to estimate the transmission time.

In Japanese Patent Laid-Open No. 6-143758, a work amount for developing print information described in a page description language into a bit image is predicted for each page, and when the predicted work amount exceeds a planned amount. Although a printer control device configured to adjust the timing of a paper feed instruction is disclosed, this prior art technique merely predicts a work amount when the FEP expands print data into image data. Since it is not available, it cannot be applied to the estimation of the required transmission time.

Further, in Japanese Patent Laid-Open No. 7-201123, the print processing time and the print end time of each job are calculated according to the program conditions of each job and the number of original image pages, and the job is transferred from the print queue to the print output unit. Although a printer device is disclosed that is configured to update the print end time of jobs in the print queue when sent, this prior art is also predictive of the print end time.

Therefore, in order to solve the above problems, according to the present invention, when a plurality of processing devices that decode PDL are connected to a printing device through a shared line, each processing device previously outputs image data in file units. An object of the present invention is to provide a printing system and a print processing method capable of determining whether to transmit in page units or page units and transmitting image data to a printing device without lowering throughput and delaying FCOT. .

[0024]

In order to achieve the above object, a first invention is to decode a print job received from a plurality of clients and a plurality of clients transmitting a print job including a plurality of pages, A printing system comprising: a plurality of processing devices that transmit image data obtained by decoding a print job; and a printing device that is connected to the plurality of processing devices via a common line and prints the image data received from the common line. Each processing device decodes the print job page by page, and a first decoding device that transmits the print job to the printing device in units of jobs when the decoding device decodes the first page of the print job. A transmission time prediction unit that estimates a transmission prediction time and a second transmission prediction time for transmitting in page units, and a first transmission time prediction unit that estimates the transmission time prediction unit. Selecting means for selecting, based on the estimated transmission time and the second estimated transmission time, whether to transmit the image data decoded by the decoding means to the common line in units of jobs or in units of pages. Characterize.

According to a second aspect of the invention, the transmission time predicting means calculates the predicted number of pages of the print job from the total data amount of the print job and the data amount of the first page, and the first calculating means, Based on the predicted number of pages calculated by the first calculating means, the data amount of the image data in which the decoding means has decoded the first page, and the line speed of the common line,
Second calculating means for calculating the first predicted transmission time;
The second transmission prediction based on the time required for decoding the first page by the decoding means, the predicted number of pages calculated by the first calculation means, and the first transmission prediction time calculated by the second calculation means. And a third calculating means for calculating time.

A third aspect of the present invention is a plurality of clients for transmitting a print job consisting of a plurality of pages, and a plurality of clients for decoding the print jobs received from the plurality of clients and transmitting image data obtained by decoding the print jobs. And a printing device connected to the plurality of processing devices via a common line for printing image data received from the common line. The predicted page number of the print job is calculated from the total data amount of the print job and the data amount of the first page, and when the first page of the print job is decoded, the data amount of the image data corresponding to the first page and The decoding required time of the first page is collected, the data amount of the image data corresponding to the collected first page, the predicted number of pages, and the previous Based on the line speed of the common line, a first predicted transmission time for transmitting the print job to the printing device in job units is calculated, and the required decoding time of the collected first page, the predicted number of pages, and the first page are calculated. A second predicted transmission time for transmitting the print job to the printing device in page units is calculated based on the first predicted transmission time, and based on the first predicted transmission time and the second predicted transmission time, It is characterized in that it is selected whether the image data is transmitted to the common line in units of jobs or in units of pages.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the system configuration of the printing system used in this embodiment and the detailed configuration of the FEP.

This printing system, as shown in FIG.
Client machines 10a to 10d on the network 11
And the FEPs 12 and 13 are connected, and the FEPs 12 and 13 are connected to the printer 15 via the common line 14.

That is, since the FEP 12 and the FEP 13 are both connected to the printer 15 via the common line 14, the FEP 13 is connected to the printer 15 while the FEP 12 is transmitting image data to the printer 15.
Image data cannot be sent to.

The client machines 10a-10d have P
FEP 1 for a print job including print data described in DL
2 or the terminal device transmitting to FEP 13.

If the FEPs 12 and 13 accept a print job having print data described in PDL,
It is a device that decodes the print data to create image data, compresses the decoded image data page by page, and outputs the compressed image data to the printer 15.

However, the FEPs 12 and 13 are configured so that it can be automatically set whether to transmit the image data page by page or collectively for each job according to the characteristics of the print data.

That is, the FEPs 12 and 13 are not fixedly set to transmit the image data in page units or in job units, but the required transmission time (hereinafter referred to as “job” in the case of transmitting image data in job units). "Transmission required time") and the transmission required time when transmitting in page units (hereinafter referred to as "page transmission required time"), and if the job transmission required time is obviously shorter, the image data When the job transmission time and the page transmission time are not significantly different from each other, the print data is transmitted to the printer 15 in page units.

Thus, the FEPs 12 and 13 are
The reason for switching between page-based transmission of image data and job-based transmission depending on the situation is F by page-based transmission.
This is because the advantage of shortening COT and the advantage of improving throughput by job unit transmission are utilized to the maximum.

If page-by-page transmission is selected and the common line 14 is occupied by another FEP, the decoding process for the next page and the like is preceded until the common line 14 becomes empty. When the common line 14 becomes available, page unit transmission is started.

At this time, if page unit transmission is started by any of the FEPs, the common line 14 is assumed to be occupied until the last page is transmitted, and when the transmission of the last page is completed, the common line 14 is completed. Is released.

The printer 15 is connected to the F
Receives the compressed image data output by EP12 or 13, decompresses the compressed image data,
It is an output device that prints out in page units.

Next, the detailed configuration of the FEP 12 will be described.

As shown in FIG. 1, the FEP 12 includes a print data processing section 12a and an image data output section 12b.
, The line status confirmation unit 12c, and the transmission time prediction unit 12d
And a transmission unit selection unit 12e.

The print data processing unit 12a decodes the print data described in PDL included in the print job for each page to create a page image, and compresses the page image to obtain compressed image data, which is the image data output unit 12a.
It is a processing unit that outputs to b.

However, in the print data processing unit 12a, when the preprocessing of the print data and the processing of the first page are completed, the actual time required for the processing is output to the transmission time prediction unit 12d.

The image data output unit 12b transmits the image data to the common line 14 in the transmission unit instructed by the transmission unit selection unit 12e after the line status confirmation unit 12c confirms the free state of the common line 14. It is a department.

Specifically, when the transmission unit selection unit 12e receives an instruction to transmit in units of jobs, the compressed image data of each page are collectively transmitted to the common line 14 and transmitted in units of pages. When the instruction to that effect is accepted, the compressed data is sequentially transmitted to the common line 14 every time the print data processing unit 12a processes the print data.

The image data output unit 12b instructs the line status confirmation unit 12c to immediately check the line status when performing page unit transmission, and the print data processing unit 12a when performing job unit transmission. When the compressed image data of the last page is received from, the line status confirmation unit 12c is instructed to check the line status.

The line status confirmation unit 12c is a processing unit for confirming whether or not the common line 14 is idle when receiving an instruction from the image data output unit 12b.

The transmission time predicting unit 12d is a processing unit for calculating the job transmission required time and the page transmission required time of the compressed image data based on the actual time received from the print data processing unit 12a.

This job transmission required time can be roughly estimated by dividing the sum of the compressed image data amount of each page by the data transfer rate, but the data transmission of the printing system is different from the case of simply performing the file transfer. It is necessary to consider a receiver of image data, that is, a printer that performs processing in page units.

Therefore, the transmission time predicting section 12d is
Predict the job transmission time by grasping the job transmission time as a function of the total of the compressed image data amount and the number of pages, and estimating the compressed image data amount of the entire job from the compressed image data amount obtained by decoding the first page. doing.

On the other hand, in the case of calculating the page transmission required time, considering that such processing is performed in parallel with the decoding and compression processing of each page and the transmission processing of the image data, the decoding and compression processing of each page is performed. It is determined depending on the total time and the time required to send the job.

Therefore, the transmission time predicting unit 12d is
The page transmission required time is taken as a function of the sum of the job transmission required time and the decryption / compression processing time, and the sum of the decryption / compression processing time is estimated from the preprocessing time and the actual time when the first page was decrypted / compressed. By doing so, the time required for page transmission is predicted.

A detailed description of the procedure for calculating the job transmission required time and page transmission required time by the transmission time predicting unit 12d will be described later.

The transmission unit selection unit 12e selects whether to transmit the compressed image data page by page or job unit, and outputs the selection result to the image data output unit 12e.
This is a processing unit that instructs b.

By using the printing system having the above configuration, it is possible to maximize the advantages of shortening FCOT by page unit transmission and the advantages of throughput improvement by job unit transmission.

Next, page unit transmission and job unit transmission performed by the FEP 12 will be described with reference to FIG. In addition,
Here, a case where the print data consists of 6 pages will be described.

FIG. 2A is a diagram showing a time chart when the FEP 12 shown in FIG. 1 performs page unit transmission.

As shown in FIG. 2A, when the FEP 12 performs page unit transmission, the print data processing unit 12a first performs a preprocessing 20 for PDL interpretation.
Note that this pre-processing means securing a working memory area, initializing the decompose routine, securing a buffer area, etc., and is necessary not only for page-based transmission but also for job-based transmission described later. Becomes

Then, in the print data processing unit 12a, following the pre-processing, decoding of print data and compression processing of image data 21a-2 are sequentially performed from the first page.
If 1f is performed, the compressed image data created for each page is sequentially output to the image data output unit 12b.

Then, the image data transmitting section 12b which receives the compressed image data transmits the compressed image data 2 when the common line 14 becomes idle.
2a to 22f are carried out.

However, for convenience of description, here, at the time of performing the decoding and compression processing 21b of the second page of the print data, the transmission processing 22a of the compressed image data of the first page 22a.
Shows the case of starting.

As described above, when the page unit transmission is performed, the process of the print data processing unit 12a and the process of the image data output unit 12b are executed in parallel.

In the following, the total processing time of the FEP 12 when page-based transmission is performed is "T1", and the transmission processing time by the image data output unit 12b in that case is "T4".

FIG. 2B is a diagram showing a time chart when the FEP 12 shown in FIG. 1 performs job unit transmission.

As shown in FIG. 2B, when the FEP 12 performs job unit transmission, the print data processing unit 12a.
After performing pre-processing 20 similar to page unit transmission,
The print data is sequentially decoded and the image data is compressed 23a to 23f from the first page, and the compressed image data created for each page is sequentially output to the image data output unit 12b.

Then, the image data sending section 12b which receives the compressed image data receives the compressed image data of the sixth page which is the last page,
If the common line 14 is in the idle state, the compressed image data transmission processes 24a to 24f are executed.

In this way, in the case of performing such job unit transmission, the processing of the image data output unit 12b is executed at the time when all the processing by the print data processing unit 12a is completed.

In the following, the processing time of the print data processing unit 12a when performing the job unit transmission is "T2", and the transmission processing time by the image data output unit 12b in that case is "T3".

Since the page transmission required time in this case is T4 and the job unit transmission required time is T3, the required times T4 and T3 required by the transmission time predicting unit 12d are calculated in advance before the image data is transmitted. To quote,
Further, the transmission unit selection unit 12e compares the two to determine whether to perform page unit transmission or job unit transmission.

Specifically, when the required time T3 is clearly shorter than the required time T4, the job unit transmission is performed with priority on the throughput, and if there is no great difference between the required times T4 and T3, FCOT is considered. Then, page unit transmission is performed.

Next, the concept of processing time prediction performed by the transmission time prediction unit 12d shown in FIG. 1 will be described.

FIG. 3 shows the transmission time predicting section 12d shown in FIG.
FIG. 6 is an explanatory diagram for explaining the concept of processing time prediction performed by FIG.

As shown in FIG. 3, in the present embodiment, the time (T5 and T6) required for the print data processing unit 12a to execute the preprocessing 20 and the decoding and compression processing 21a for the first page and the first Compressed image data amount of page (D1)
Then, the transmission time predicting unit 12d calculates the page transmission required time (T4) and the job transmission required time (T3) based on the record data T5, T6 and D1.

Specifically, the transmission time predicting unit 12d first calculates the job transmission required time (T3) using the calculation formula of T3 = D1 × P / V + P × α + β. However, 'P' indicates the predicted number of pages of image data, 'V' indicates the data transfer rate, and'α 'and'
β'denotes a constant.

Then, regarding this predicted page number P,
By analogy from the data amount of all print data and the data amount of the first page, appropriate values are set for the constants α and β using the statistical test results.

That is, here, the job transmission required time (T3) is estimated from the compressed image data amount (D1) of the first page by the total compressed image data amount (D1 ×).
P) and the predicted number of pages of print data (P).

The reason why the job transmission required time (T3) is calculated in consideration of the predicted number of pages (P) is that the internal processing of the printer 15 which performs the printing processing in page units while receiving the compressed image data is taken into consideration. Is.

By performing the above calculation, the transmission time predicting section 12d can predict the job transmission required time (T3).

Next, the transmission time predicting unit 12d obtains the time required for decoding and compression (T2) of the print data when performing the job-unit transmission process, and the time required (T2) and the time required for job transmission (T3). The page transmission required time (T4) is calculated based on

Specifically, the time required for decoding and compression of print data (T2) is calculated using the calculation formula of T2 = T5 + T6 × P, and T4 = T2 × γ + T3 × δ− (T5 + T
Calculate the page transmission time (T4) using the calculation formula in 6). However, “γ” and “δ” are constants, and appropriate values are set using the statistical test results.

In other words, here, the page transmission required time (T4) is correlated with the print data decoding and compression required time (T2) and the job transmission required time (T3) in the case of performing the job unit transmission processing. Considers one point.

By performing the above calculation, the transmission time predicting section 12d can predict the page transmission required time (T4).

The concept of processing time prediction performed by the transmission time prediction unit 12d has been described above.

Next, the processing procedure of the FEP 12 will be described.

FIG. 4 is a flowchart showing the processing procedure of the FEP 12 shown in FIG.

As shown in FIG. 4, the print data processing unit 12
a is the decoding and compression of the first page to create the compressed image data of the first page (step 401), the preprocessing time (T5) of the print job, the processing time (T6) of the first page, and the PDL file. The processing ratio (A) of the first page and the compressed image data size (B) of the first page in the whole are sampled (step 402) and output to the transmission time prediction unit 12d.

Since this "A" is the processing rate of the first page in the entire PDL file, its reciprocal "1 / A" corresponds to the number of pages.

Then, the transmission time predicting section 12d which has received these actual data, decodes and compresses the print data in the case of performing the transmission processing for each job based on the calculation formula T2 = T5 + T6 / A. T2) is calculated (step 403), and the job transmission required time (T3) is calculated based on the calculation formula T3 = B / (A × V) + α / A + β (step 404).

Then, the transmission time predicting unit 12d uses the calculated T2 and T3 to calculate T4 = T2 × γ + T3 × δ− (T5 + T).
6), the page transmission required time (T4) is calculated (step 405), and T3 and T4 are output to the transmission unit selection unit 12e.

Then, in the transmission unit selecting section 12e,
Job transmission time (T3) and page transmission time (T
4) is compared (step 406), T4 is T3 + ε
(However, 'ε' is a predetermined value.) If it is larger than the predetermined value, the image data output unit 12b is instructed to transmit in units of jobs, and the image data output unit 12b that has received the instruction causes the page The compressed image data for each is sequentially stored in the buffer and then sent to the common line 14 in units of jobs (step 407).

On the other hand, when T4 is equal to or less than T3 + ε (where'ε 'is a predetermined value), the image data output unit 12b is instructed to transmit in page units and the instruction is issued. Received image data output unit 12b
Confirms the vacant state of the common line and sequentially sends the compressed image data page by page to the common line 14 (step 408).

By performing the above series of processing, the FEP
12, page-based transmission or job-based transmission can be automatically switched according to the characteristics of the print job.

Next, the relationship between the estimated time and the actual measurement result when the present invention is applied to various print jobs will be described with reference to FIG.

FIG. 5 is a diagram showing the relationship between measured values and calculated values when the present invention is applied to print jobs having different page numbers and image data sizes.

However, here, the transfer rate P is 275.4.
(KB / sec), the constant α is 0.320 (sec), the constant β is 5.960 (sec), the constant γ is 0.279, and the constant δ is 0.976.

FIG. 5 shows T 1 for jobs 1 to 9 in which the number of pages and the image data size are different.
The actual values of 1, T2 and T3 and the calculated values of T1 and T3 are shown.

When the measured and calculated values for T1 are compared by the least squares method, a 99.97% accuracy is obtained, and the measured and calculated values for T3 are compared by the least squares method. A certainty of 99.38% is obtained.

That is, it can be seen that the processing time estimation used in the present invention can obtain an extremely accurate accuracy of 99% or more when applied to jobs 1 to 9 having different page numbers and image data sizes.

As described above, in the present embodiment,
When the FEP 12 receives a print job described in PDL transmitted from the clients 10a to 10d, the print data processing unit 12a performs preprocessing of the print job and decoding and compression processing of the first page, and outputs the result data. Based on the prediction result, the transmission time predicting unit 12d predicts the transmission time when the job unit transmission is performed and when the page unit transmission is performed, and the transmission unit selecting unit 12e performs the job unit transmission or the page unit transmission based on the estimation result. Since it is configured to instruct the image data output unit 12b whether to perform the transmission, the throughput is reduced by taking advantage of the throughput advantage when performing the job unit transmission and the FCOT advantage when performing the page unit transmission. Also, the image data can be transmitted to the printer 15 while reducing the delay of FCOT.

Although the FEPs 12 and 13 are connected to the printer 15 via the common line 14 in the present embodiment, the printer 15 is connected to the network 11 and the FEPs 12 and 13 are connected via the network 11. Thirteen
It is also possible to connect the printer 15 and the printer 15.

[0100]

As described in detail above, according to the present invention, when each processing device decodes the first page of a print job, the first transmission prediction for transmitting the print job to the printing device in units of jobs. Whether the time and the second estimated transmission time to be transmitted in page units are estimated in advance, and the image data is transmitted to the common line in units of jobs based on the estimated first estimated transmission time and second estimated transmission time Since it is configured to select whether to transmit in page units, the following effects can be obtained.

(1) It is possible to improve the throughput of the printing system by reducing the time when each processing device occupies a common line.

(2) FCOT is shortened by transmitting image data in page units when there is no great difference in the required transmission time between transmitting image data in job units and image data in page units. It becomes possible.

Further, according to the present invention, the predicted page number of the print job is calculated from the total data amount of the print job and the data amount of the first page, and the calculated predicted page number and the data of the image data obtained by decoding the first page. The first estimated transmission time is calculated based on the volume and the line speed of the common line.
Since the second predicted transmission time is calculated based on the time required for decoding the page, the predicted number of pages, and the first predicted transmission time, when a part of the print job is decoded,
It is possible to predict the required transmission time when image data is transmitted on a job basis and the required transmission time when image data is transmitted on a page basis.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration of a printing system used in this embodiment and a detailed configuration of an FEP.

FIG. 2 is a diagram showing a time chart when the FEP shown in FIG. 1 performs page unit transmission and job unit transmission.

FIG. 3 is a diagram for explaining the concept of processing time prediction performed by a transmission time prediction unit shown in FIG.

FIG. 4 is a flowchart showing a processing procedure of FEP shown in FIG.

FIG. 5 is a diagram showing actual values and calculated values when the FEP shown in FIG. 1 processes various print jobs.

FIG. 6 is a diagram showing a time chart in a conventional network publishing system.

[Explanation of symbols]

10a, 10b, 10c ... Client machine, 11 ...
Network, 12, 13 ... FEP, 14 ... Common line, 15 ... Printer, 12a ... Print data processing unit, 1
2b ... Image data output unit, 12c ... Line status confirmation unit, 12d ... Transmission time prediction unit, 12e ... Transmission unit selection unit

Claims (3)

[Claims] 1. A plurality of clients for transmitting a print job including a plurality of pages, a plurality of processing devices for decoding a print job received from the plurality of clients and transmitting image data obtained by decoding the print job, In a printing system having a printing device connected to a plurality of processing devices via a common line and performing a print process of image data received from the common line, each processing device decodes the print job page by page. And a first predicted transmission time for transmitting the print job to the printing apparatus in units of jobs and a second predicted transmission time for transmission in units of pages when the decoding unit decodes the first page of the print job. Based on the estimated transmission time estimation means and the first estimated transmission time and the second estimated transmission time estimated by the transmission time estimation means, Printing system decoding means is characterized by comprising a selection means for selecting whether to transmit the image data decoded by either page units transmitted in units of jobs to the common line. 2. The transmission time predicting means includes a first calculating means for calculating a predicted number of pages of a print job from a total data amount of the print job and a data amount of the first page, and the first calculating means. Second calculating means for calculating the first predicted transmission time based on the calculated predicted page number, the data amount of the image data obtained by the decoding means decoding the first page, and the line speed of the common line; The second predicted transmission time is based on the time required for decoding the first page by the decoding means, the predicted number of pages calculated by the first calculation means, and the first predicted transmission time calculated by the second calculation means. The printing system according to claim 1, further comprising a third calculating unit that calculates 3. A plurality of clients for transmitting a print job including a plurality of pages, a plurality of processing devices for decoding the print jobs received from the plurality of clients, and transmitting image data obtained by decoding the print jobs, In a print processing method of a printing system having a printing device that is connected to a plurality of processing devices via a common line and prints image data received from the common line, each processing device is configured to have a total data amount of the print job. And the predicted number of pages of the print job is calculated from the data amount of the first page, and when the first page of the print job is decoded, the data amount of the image data corresponding to the first page and the decoding request of the first page are required. The amount of image data corresponding to the collected first page, the estimated number of pages, and the line of the common line are collected. A first predicted transmission time for transmitting the print job to the printing device on a job-by-job basis based on the frequency, and the decoding required time of the collected first page, the predicted number of pages, and the first predicted transmission. A second predicted transmission time for transmitting the print job to the printing apparatus page by page is calculated based on the time, and the image data is calculated based on the first predicted transmission time and the second predicted transmission time. A print processing method in a printing system, characterized in that it is selected whether it is sent to the common line in units of jobs or pages.