JPH11110168A - Information processing device and method therefor, print system, and memory medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dynamically switch the coding systems according to the state of a printer engine and to improve the print processing efficiency. SOLUTION: A coding part 301 codes the image data by a Pack Bits system of a high processing speed, and a coding part 302 codes the image data by a JBIG(Joint Bi-level Image Coding Expert Group) system of high coding efficiency. An engine monitoring part 205 monitors the state of a printer engine 140. A printer driver 203 dynamically switches both coding parts based on the state information on the engine 140 (engine information) that is informed from the part 205.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing apparatus and method, a printing system, and a memory medium, and more particularly to an information processing apparatus and method for supplying image information to a printing apparatus, and printing including the information processing apparatus. The present invention relates to a system and a memory medium used for controlling the information processing apparatus.

[0002]

2. Description of the Related Art Generally, in a printer system in which a host computer and a printer are connected, the host computer operates as follows.

Here, a host computer equipped with Windows NT and Windows 95 (both are registered trademarks of Microsoft Corporation in the United States) as basic software (OS) will be described. When instructing printing from so-called application software such as word processing software or presentation software that operates on these basic software, first, the application software first executes the application program interface (Application Program Interface;
API) and call the system (in this case, Graphic
Device Interface (hereinafter, GDI) is instructed to execute drawing processing and print control processing accompanying the drawing processing.

[0004] In response to this instruction, the system (GDI)
Calls a software module called a printer driver that controls an actual physical printer connected to a host computer, and gives instructions to the software module. Actual print data is generated by a part called a printer driver. here,
Focusing on the contents of the generated print data and the processing form thereof, printer drivers are roughly classified into the following two types.

(1) Image printer driver This type of printer driver generates image data and transmits it to the printer. Drivers for relatively low-cost printers such as ink-jet serial printers are often of this type.

(2) PDL Printer Driver In this type of printer driver, a PDL (Page Des
Data (PDL data) composed of commands described in Cription Language) is generated and transmitted to the printer. When this type of printer driver is installed in a host computer, it is necessary for the printer to generate image data based on PDL data. There are many printer drivers of this type for controlling a page printer typified by a laser beam printer or the like.

(3) Printer driver that mixes the above (1) and (2) In this type of printer driver, characters, line drawings, figures, and the like are represented in a format similar to PDL data, and graphics and images are image data. Generate the expressed print data and send it to the printer. If necessary, combine them on the printer side. However, since a printer corresponding to this type of printer driver does not have font data, the host computer generates image data of all necessary character data and downloads and uses the image data to the printer. .

In the printer driver of the type (1) or (3), since image data is generated on the host computer side, the processing load on the host computer side becomes larger than that of the printer driver of the type (2). .
In addition, since the data to be transferred includes image data, there is an upper limit, but the amount of print data is generally large. For this reason, there is a printer driver in which the time required for data transfer is reduced by performing encoding processing on the image data to be transferred and reducing the amount of data before transferring the data to the printer.

[0009]

However, the following problems are conceivable in the above-mentioned printer system. For example, in the above printer driver, the data encoding method used when generating print data to be transferred to the printer is fixed to one method. Therefore, when the processing capacity of the host computer is sufficiently high with respect to the processing capacity (engine speed) of the printer, the host computer can send the print data to the printer despite the completion of the print data generation processing. Is not completed, that is, a so-called transmission waiting state. In this case, the host computer waits for the transmission to be completed, although the processing capacity can be originally allocated to other processing.

The problem is that the encoding method can be dynamically changed, and if it is expected that the transmission will be in a transmission waiting state, extra time is required for the encoding process to reduce the amount of print data. It should be solved by

As described above, by efficiently utilizing the processing capacity of the host computer to reduce the data amount of the print data, it is possible to secure a margin of the receiving buffer or the print spooler of the printer. Also, in a system in which a host computer and a printer are connected via a network, the traffic of the network can be smoothed by reducing the amount of print data. In particular, the effect is great in a system employing an image-based printer driver.

However, while the above effects can be obtained by dynamically changing the encoding method,
There is a problem in easily determining the change method. For example, a method of dynamically switching the encoding method according to the type of image is conceivable. In this case, however, there is a problem in that determination of the type of image requires complicated processing. That is, by selecting an appropriate encoding method according to the type of image, the data amount of the print data can be effectively reduced, and the transfer time of the print data can be reduced. There is a problem that it takes a long time to determine the type of an image, and the possibility that an excessively long time is required for an encoding process. In this case, the time when the printing process of the first page is started on the printer side is delayed, and as a result, it may take a long time to complete the printing process.

Furthermore, when a page printer such as a laser beam printer is used, it is necessary to suppress the occurrence of cycle down in order to execute an efficient printing process. Cycle down means that after the rotation of the drum for forming an image of one page (frame) ends,
If the preparation of the image data of the next page is not completed by the rotation operation of the next drum, the drum is meaningless because the image of the next page cannot be formed in the rotation operation of the next drum. ) Causes a time loss.

Usually, the drum for an engine of a monochrome laser beam printer has a small drum diameter and the time required for one rotation of the drum is short, so that the effect of the cycle down is relatively small. On the other hand, in a printer engine in which the intermediate transfer member is a belt type, it takes several seconds, for example, for the belt to rotate once. In order to execute the print processing at the maximum throughput by making the most of the engine performance, it is important to suppress the occurrence of cycle down.

Therefore, there is also a problem that an excessive load is applied to the host computer, and it is desired to appropriately determine a load balance between the host computer and the printer.

The present invention has been made based on the above idea, and has as its object to increase the efficiency of the printing process.

[0017]

An information processing apparatus according to the present invention is an information processing apparatus for supplying image information to a printing apparatus, wherein a monitoring means for monitoring a state of the printing apparatus, and a state of the printing apparatus. Encoding means for selecting any one of a plurality of encoding schemes different from each other, and encoding the image information according to the selected encoding scheme, and printing the encoded image information Transfer means for transferring to the device.

In the above information processing apparatus, it is preferable that the coding means determines a coding method for each predetermined unit.

In the above information processing apparatus, it is preferable that the predetermined unit is a page unit, a frame unit, or a band unit.

In the above information processing apparatus, the encoding means may include, as an encoding method, a first encoding method having a relatively high processing speed.
It is preferable to be able to select the encoding method of (1) or the second encoding method having relatively high encoding efficiency.

In the above information processing apparatus, it is preferable that the first coding method has a relatively low coding efficiency and the second coding method has a relatively low processing speed.

In the above information processing apparatus, when the operation of the printing apparatus is paused, the encoding unit relatively reduces the processing speed of the predetermined unit of image information to be encoded first. It is preferable to perform encoding using a fast encoding method.

In the above information processing apparatus, it is preferable that the encoding means encodes the subsequent image information by using an encoding method having a relatively high encoding efficiency.

An information processing method according to the present invention is an information processing method for supplying image information to a printing apparatus, wherein a monitoring step for monitoring the state of the printing apparatus and a monitoring step differ from each other based on the state of the printing apparatus. An encoding step of selecting any one of a plurality of encoding schemes and encoding image information according to the selected encoding scheme; and a transfer step of transmitting the encoded image information to the printing apparatus. And characterized in that:

Another information processing apparatus according to the present invention is an information processing apparatus for supplying image information to a printing apparatus, and includes a first encoding method having a relatively high processing speed or a relatively low encoding efficiency. Encoding means for encoding the image information according to a high second encoding method, and transfer means for transferring the encoded image information to the printing apparatus, wherein the encoding means suspends the operation of the printing apparatus In this case, the first unit of image information to be encoded first is encoded by the first method.

In the above another information processing apparatus, it is preferable that the encoding unit encodes subsequent image information by the second method.

In the above information processing apparatus, it is preferable that the predetermined unit is a page unit, a frame unit, or a band unit.

Another information processing method according to the present invention is an information processing method for supplying image information to a printing apparatus, wherein the first encoding method has a relatively high processing speed or has a relatively low encoding efficiency. An encoding step of encoding the image information according to a high second encoding method; and a transfer step of transmitting the encoded image information to the printing apparatus, wherein the operation of the printing apparatus pauses in the encoding step. In such a case, it is preferable that the first unit of image information to be encoded first be encoded by the first method.

[0029] A printing system according to the present invention is a printing system having an information processing device and a printing device that perform communication via a communication line, wherein the information processing device monitors a status of the printing device. Encoding means for selecting any one of a plurality of encoding methods different from each other based on a state of the printing apparatus and encoding image information according to the selected encoding method; Transfer means for transferring the decoded image information to the printing apparatus, the printing apparatus comprising: a decoding means for decoding the image information transferred from the information processing apparatus; Output means for outputting an image.

A memory medium according to the present invention is a memory medium storing a control program code of an information processing apparatus for supplying image information to a printing apparatus, wherein a code for a monitoring step for monitoring a state of the printing apparatus is provided. A code for an encoding step of selecting any one of a plurality of encoding methods different from each other based on the state of the printing apparatus and encoding image information according to the selected encoding method; And a code of a transfer step of transferring the obtained image information to the printing apparatus.

Another memory medium according to the present invention is a memory medium storing a control program code of an information processing apparatus for supplying image information to a printing apparatus, wherein the first encoding method has a relatively high processing speed. Or includes a code of an encoding step of encoding image information by a second encoding scheme having a relatively high encoding efficiency, and a code of a transfer step of transferring the encoded image information to the printing apparatus, In the encoding step, when the operation of the printing apparatus is paused,
The image information of a predetermined unit to be encoded first is encoded by the first method.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a printer system according to a preferred embodiment of the present invention will be described. The printer system according to this embodiment relates to a system that employs an image-based printer driver. When print data is generated on the host computer side, the first page print data is processed with respect to the generated image data. Encoding processing with an emphasis on speed (encoding processing with a relatively high processing speed) is performed, and with respect to print data of the second and subsequent pages, encoding processing (e.g. (Encoding process with relatively high encoding efficiency), and transfer the data to the printer.

As a result, the amount of print data transferred to the printer can be reduced. More specifically, without delaying the timing of starting the printer engine, the overall amount of print data is reduced, and memory means for temporarily storing network traffic and print data (for example, receiving buffer,
The pressure on the print spooler can be reduced. In particular, when a printer having a printer engine with a relatively long paper feed time is employed, it is easy to complete the processing on the host computer side for each page in a cycle in which the printer forms an image. Thus, only the data amount of the print data can be reduced without lowering the overall performance.

In the PDL printer driver, PDL data may have an enormous data amount depending on the complexity of drawing contents, and the upper limit of the data amount is not limited. On the other hand, in the image-based printer driver, the print data is actually image data in any case of executing drawing, so the data amount is determined by the paper size and the image resolution.

That is, when an image printer driver is used, the maximum time required for encoding image data can be easily estimated in advance when the load on the host computer is light.

Therefore, in this embodiment, in consideration of the above-described characteristics of a system employing an image-based printer driver, the time required for encoding image data and the time required for print processing on the printer side are determined. Thus, the data amount of the print data is reduced by dynamically switching the encoding method and the decoding method.

Hereinafter, a printer system according to a preferred embodiment of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a printer system according to a preferred embodiment of the present invention. In this printer system, a host computer 200 and a printer 1
00 is connected via a communication cable 150.

The host computer 200 transfers print data including information about an image and a control code (command) to the printer 100 via the communication cable 150.
The printer 100 forms an output image based on the print data.

The printer 100 includes a formatter control unit 1
10, operation panel unit 120, output control unit 13
0, a printer engine 140 is provided. In this embodiment, a monochrome laser printer (LBP) is assumed as the printer 100.
The present invention is not limited to the BP, and can be applied to an inkjet printer and other types of printers irrespective of color / monochrome in addition to color LBP.

In the printer 100, a formatter control section 110 includes an interface (I / F) section 111 as a connection means with a host computer, and a reception buffer 1121 for temporarily storing and managing received print data and the like. A transmission buffer 1122 for temporarily storing and managing transmission data, a command analysis unit 113 for analyzing print data, a print control processing execution unit 114 for controlling execution of print processing, It has a drawing processing execution unit 115 to be controlled and a page memory 116.

The interface (I / F) unit 111 is a communication unit for communicating print data and other data with the host computer 200. The print data received by the interface unit 111 is stored in a reception buffer 112 serving as a storage unit for temporarily storing the print data.
1 are sequentially stored. The stored print data is stored in the command analysis unit 113 or the drawing process execution unit 11 as necessary.
5 for processing. Command analyzer 1
The control unit 13 is controlled by a control program capable of supporting various print control command systems and print job control languages. The command analysis unit 113 executes the drawing processing execution unit 1 based on commands related to drawing characters, graphics, images, and the like.
15 to control the drawing process, and based on commands other than drawing, such as a paper feed selection and a reset command, to the print control process execution unit 114 to control the printing process.

The drawing process execution section 115 sequentially develops (draws) each object such as characters and images in the page memory 116. When decoding the encoded image data and developing the decoded image data in the page memory, the decoding processing unit 1151 in the drawing processing execution unit 115 performs a decoding process on the image data.

Here, two band memory areas are provided in the page memory 116, and an image is processed in band units while replacing the band memory used for the expansion processing with the band memory used for shipping the video signal to the printer engine 140. The page memory 116 may be managed by the following banding control, or if a memory having a sufficient capacity can be mounted in the printer 100, an area where one page can be expanded may be secured as the page memory 116.

The formatter control unit 110 includes a central processing unit (CPU) and a read only memory (RO).
M), a computer system using a random access memory (RAM) or the like.
In addition, the processing of each unit may be processed in a time-sharing manner under a multitask monitor (real-time OS).
A configuration in which hardware is prepared and processed independently is also possible.

The operation panel 120 constitutes a user interface for setting the operation of the printer 100 and displaying various states. Output control unit 130
Converts the contents of the page memory 116 into a video signal,
The video signal is transferred to the printer engine 140. The printer engine 140 forms a visible image on recording paper based on the received video signal.

Next, the configuration of the host computer 200 will be described. The host computer 200 has a keyboard 210 and a mouse (pointing device) 211 as input devices, and a display monitor 220 as a display device.

The host computer 200 is an MS-DO
It operates under a basic OS such as S, Windows, or UNIX. The host computer 200 includes application software 201 and G which is a part of the functions of the basic OS.
A DI 202, a printer driver 203 as print data generating means, a print spooler 204 for temporarily storing data generated by the printer driver 203,
Engine monitoring unit 205 that monitors the status of printer 100
And

Although the names and functional frameworks of the above-mentioned parts may be slightly different depending on the basic OS, it is only necessary to provide a module capable of realizing the same functions. For example, a module called a GDI or a printer driver is specific to Windows 95 or Windows NT, and can be realized by a module called a graphic kernel or a print filter in another basic OS. The print spooler 204 can also be realized by incorporating processing in a module called a print queue.

Generally, the host computer 200 including these components is provided by a central processing unit (C).
PU), read only memory (ROM), random access memory (RAM), hard disk drive (H
Under the hardware such as DD) and various input / output control units (I / O), software called basic software controls the control, and the application software operates under the basic software. . The printer driver 203 also
It is positioned as one of the application software. The application 201 refers to application software that operates on basic software, for example, for document processing or spreadsheet calculation. In addition, a memory medium (for example, ROM,
It goes without saying that a RAM, a disk, etc.) constitute a legal invention.

Next, as an operation example of the printer system, a case where image editing software is used as the application 201 will be described.

When the user mainly performs image editing work using the application 201 and prints the edited image, the user selects a print menu from the menu on the display screen of the display monitor 220 with the mouse 211 or the like. In addition, the user instructs execution of printing after performing desired settings.

In response, the application 201
Calls the GDI 202 which is a part of the function of the basic OS. The GDI 202 includes a basic function group for controlling a display device such as a screen display or a print output or a print device. Application software of various companies uses the basic function group to execute a model (hardware) operation. It operates regardless of the difference.

The GDI 202 fetches information such as the drawing capability and print resolution of the printing device (in this case, the printer 100) from the printer driver 203 that manages information depending on the printer model. The function is processed, and a function provided by the printer driver to the GDI 202 is called according to the processing content. This function uses a predetermined interface (Device Driver Interface; DD)
A printer driver is created mainly for data conversion from this interface to an actual printer.

The printer driver 203 is a GDI 202
Printer 1 based on the received DDI information and the print environment set by its own graphical user interface (GUI).
The image is developed on the page memory 2032 at the resolution of the 00 side.

Here, a case is considered in which the image is edited by the image editing software and printing is instructed. In this case, the printer driver 203 stores the actual image data (original data), the original resolution,
Information on the arrangement position and size of the image with respect to the destination (printer side) is given along with the information on the width and height, and the resolution conversion processing (enlargement / reduction processing) of the image data is performed based on the information. , The image is developed in the page memory 2032.

After an image for one page is developed in the page memory 2032, the image data is encoded by the encoding processing unit 2033. In this embodiment, the encoding processing unit 2033 includes: 1) PackBi
It is assumed that the encoding process can be executed by two types of encoding methods, ts method and 2) JBIG method.

Here, the PackBits method is an algorithm having a relatively high processing speed when performing data encoding, but having a relatively low encoding efficiency. Meanwhile, J
BIG (Joint Bi-level Image Coding Expert Group)
The method is ISO / I as a data coding method for a binary image.
This is a data encoding system internationally standardized by TU-T.
This is a conventional binary image coding standardization method, which is applied to facsimile and the like.
d Relative element address designate), which is 1.2 to 1.5 times higher for character-centric general documents and 3 to 20 times higher for pseudo halftone images such as dither and halftone dots. Although efficiency can be obtained, data encoding processing by software requires a relatively long time. Note that these data encoding algorithms are known.

This embodiment uses two similar encoding systems in terms of a technique for reducing the amount of data by eliminating waste (repetition, blanks, etc.) in the data as described above. Two coding schemes that conflict with each other in terms of speed and coding efficiency are employed.

Here, from the viewpoint of the processing speed of the encoding, it is preferable to execute the encoding processing and the decoding processing by hardware. In particular, on the printer side, it is preferable that the decoding process be executed at high speed by hardware.

Image data encoded by one of the two encoding methods is stored in the print spooler 204 as print data after an image drawing command and parameters conforming to the command system of the printer 100 are added.

The print data stored in the print spooler 204 is transferred to the printer 100 via the interface unit 212.

FIG. 2 is a conceptual diagram for explaining the operation of the printer system shown in FIG. When one page of image data is generated in the page memory 2032 by the image generation processing unit 2031, the printer driver 203
Queries the engine monitoring unit 205 about the state of the printer engine 140.

For example, when a suitable time has elapsed since the printer 100 last executed the printing process or immediately after the power was turned on, the temperature of the fixing unit and the number of rotations of the polygon mirror are required for printing. It is not in the state (steady state). In this case, it takes time for the printer to be ready for printing. On the other hand, immediately after the execution of the printing process, the temperature of the fixing unit is likely to be the steady temperature, and the printer engine 140 can often be started immediately. Thus, depending on the state of the printer 100,
Throughput varies widely.

Therefore, the engine monitoring unit 205 acquires information indicating the status of the printer 100 from the printer 100 via the communication cable 150, and dynamically switches the encoding method according to the status of the printer 100.

In the encoding processing unit 2033, for example, if a predetermined time has elapsed since the printer 100 executed the last print processing, the encoding unit of the PackBits system is used for the first page of the print job. The image data is encoded by 301 and J
The image data is encoded by the encoding unit 302 of the BIG system.

The printer 100 that has received the print data
Based on the control information included in the print data, the encoding method of the image data included in the print data is recognized. If the image data is encoded by the PackBits method (encoding unit 301), the image data is directly stored in the memory 313. On the other hand, if the image data is in the JBIG format (encoding unit 3
02), the image data is decoded by the decoding unit 311 of the JBIG system, then encoded again by the encoding unit 312 of the PackBits system, and then stored in the memory 313. .

Next, the image data (image data encoded by the PackBits method) stored in the memory 313 is decoded by the PackBits decoding unit 31.
4 while being rendered in the page memory 116 while being decoded.

In the example shown in FIG.
Since there is room in the processing on the 00 side, the image data is encoded by software, and the image data is decoded on the printer 100 side by hardware in order to suppress the cycle down.

FIG. 3 is a diagram comparing the operation of the conventional printer system and the operation of the printer system shown in FIG. 1 when a print job consisting of three pages is executed. In the figure, A shows the operation of the conventional printer system, and B shows the operation of the printer system shown in FIG.

The processing on the host computer side is roughly divided into three steps of image data generation processing (image generation processing in the figure), encoding processing, and data transfer processing.
Then, one print job is completed by repeating these three steps for each page.

Normally, data transfer processing is performed by DMA (Direct
Since the transfer is performed by memory access), the load on the CPU is small. Therefore, the image data generation processing and the data transfer processing mainly performed by the printer driver are executed in parallel.

Therefore, as shown in FIG. 3, immediately after the encoding process is completed, the process of generating the image data of the next page can be started. In FIG. 3, the encoding process using the PackBits method is described as “PB process”, and the encoding process using the JBIG method is described as “JBIG process”.

In FIG. 3, the timing at which information (engine information) indicating the status of the printer engine 140 is first obtained from the engine monitoring unit 205, the timing at which engine information is obtained for the second time, and the timing at which engine information is obtained at the third time It is.

For example, when the printer 100 is in a state immediately after power-on, the timing of
Returns engine information indicating "engine stopped" to the engine monitoring unit 205. In this case, in the printer system according to the present embodiment, the printer driver 203 determines that the printing process can be completed more quickly if the printer engine 140 is started immediately, and the encoding process is performed for the first page. P that takes less time
The encoding unit 301 according to the ackBits method encodes the image data and transmits a start command of the printer engine 140 via the communication cable 111.

Upon receiving this start command, the printer 100 shifts the temperature of the fixing unit and the rotation speed of the polygon mirror driving motor to a steady state. “P” attached to FIG. 3 indicates a timing at which a start command is transmitted. For the second page and the third page, for example, unless a start command is transmitted at the timing shown in the figure, a cycle down occurs, so that the highest throughput cannot be obtained.

The printer driver 203 of the host computer 200 acquires the engine information from the engine monitoring unit 205 at the timing of the second page, and transmits the image data to the encoding unit 301 or 302 according to the content. It is selected as an encoding unit to be used for the generation process.

Here, the engine monitoring unit 205 responds to an inquiry from the printer driver 203 to
Requesting the transmission of engine information to 00. At this time,
Since the printer 100 is in operation, the printer 100
Sends engine information to the engine monitoring unit 205 that a cycle down will not occur if a start command is issued after Rt1 second from the current time. Thereby, the engine monitoring unit 205 can notify the printer driver 203 of the engine information.

The printer driver 203 which has acquired the engine information determines whether or not the encoding process by the JBIG method is possible without causing a cycle down based on the engine information (Rt1). Specifically, the printer driver 203 calculates a maximum time E2max required for encoding by the JBIG method and a data transfer time (calculated based on a data amount and a data transfer speed). And
The total time of both of them is compared with Rt1, and
If al is equal to or less than Rt1, the encoding unit is set to the encoding unit 302 of the JBIG system (priority is given to reducing the data amount). If total is greater than Rt1, the encoding unit is set to Packbits. Encoding unit 3
01 (priority is given to shortening the processing time).

One print job is completed by repeating the same processing for the subsequent third page.

As described above, by dynamically switching the encoding method according to the state of the printer engine 140, the data amount of the print data transferred between the host computer and the printer without lowering the throughput. Can be reduced. Here, for example, when a printer of a type that does not require a long time to start the printer engine is adopted, the encoding method can be determined without confirming the state of the printer engine (for example, the first page can be determined). PackBits method, and the second and subsequent pages are JBIG methods).

FIG. 4 is a flowchart showing the operation of the host computer. When a print process is instructed from the application 201, the printer driver 203 is initialized in step S401. In this initialization process, the work area of the printer driver 203 is initialized, and a value passed from the GDI 202 is set to a predetermined variable.

In step S402, the printer driver 203 (image generation processing unit 2031) initializes a page memory 2031 which is an area for developing image data.

In step S 403, a drawing routine corresponding to a drawing command passed from the GDI 202 to the image data generating unit 2031 is called, and the page memory 20 is called.
The image data is expanded to 32. For example, GDI20
When receiving the straight line drawing command from 2, the image data generating unit 2031 calls the corresponding drawing routine and
A straight line is drawn in the page memory 2032.

In step S404, it is checked whether or not the processing of the drawing command for one page has been completed. If not completed, the process returns to step S403.
Go to 5.

In step S405, the printer driver 203 requests the engine monitoring unit 205 to notify the engine information. In response, the engine monitoring unit 205 acquires engine information from the printer 100 and notifies the printer driver 203 of the engine information.

In step S406, as described above, the printer driver 203 uses the PackBits encoding unit 301 or the JBI
It selects which one of the encoding units 302 of the G system is used.

When the encoding unit 301 is selected (priority is given to shortening the processing time), the image data in the page memory 2032 is encoded by the encoding unit 301 in step S407. On the other hand, encoding section 302
Is selected (priority is given to reducing the data amount), the encoding unit 302 encodes the image data in the page memory 2032 in step S408.

In step S409, print data including encoded image data is generated, and
Transfer to 0.

In step S410, it is determined whether or not the transfer of the print data has been completed for all the pages. If the transfer has not been completed, the process returns to step S402, and if completed, the series of processes ends.

The processing shown in the flowchart of FIG. 4 is processing when one print job is executed alone, but the same processing can be performed when a plurality of print jobs are executed continuously. In this case, if the cycle down does not occur between the print jobs, the image data can also be encoded by the encoding unit 302 based on the JBIG method for the first job of the second and subsequent print jobs.

Although the above embodiment relates to a printer system having two paths for encoding and decoding image data, it is also effective to have three or more paths. In this case, the data amount of the print data can be further reduced.

The above embodiment relates to a printer system having a page memory for one page on the host computer side.
Image data may be generated for each band.

Further, it goes without saying that the above embodiment is applicable to a color printer. The page memory and the band memory may be configured in units of a plurality of planes, for example, three planes in the RGB format and four planes in the YMCK format.

Further, since the above embodiment relates to a page printer, the print data is processed in units of pages. For example, a predetermined number of lines may be used as a unit. When the above-described printer is applied to a color printer, for example, frames (for example, Y, M, C,
The print data may be processed in units of (one image of K).

As long as the functions of the present invention are executed, the system may be a single device, a system including a plurality of devices, or a system in which processing is performed via a network such as a LAN. good. Here, in a system where processing is performed via a network, there is no guarantee that communication can be performed in real time between the host computer side and the printer side, so the engine monitoring unit may obtain the status in real time from the printer. Instead, it can be realized by observing the state in discrete time at a certain period, and emulating the state change of the engine on the host computer side using a pseudo model based on the observation result.

Further, an object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and to provide a computer (or CPU) of the system or apparatus.
And MPU) read and execute the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium storing the program code constitutes the present invention.

Examples of a storage medium for supplying the program code include a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, and CD.
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided on a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

According to this embodiment, the amount of print data can be reduced, so that the time required for transfer of print data can be reduced, the load of traffic that adversely affects the network can be reduced, and A buffer margin can be secured. In the future, it is expected that the resolution will be higher and the image data of high definition will be handled, and the effect can be said to be enormous.

[0103]

According to the present invention, the printing process is made more efficient.

[0104]

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a printer system according to a preferred embodiment of the present invention.

FIG. 2 is a conceptual diagram for explaining the operation of the printer system shown in FIG.

FIG. 3 is a diagram comparing the operation of the conventional printer system and the operation of the printer system shown in FIG. 1 when a print job including three pages is executed.

FIG. 4 is a flowchart showing an operation of the host computer.

[Explanation of symbols]

 Reference Signs List 100 printer 110 formatter control unit 111 interface 1121 reception buffer 1122 transmission buffer 113 command analysis unit 114 print control processing execution unit 115 drawing processing execution unit 1151 decryption processing unit 116 page memory 120 operation panel 130 output control unit 140 printer engine 150 interface cable 200 Host computer 201 Application software 202 GDI 203 Printer driver 2031 Image generation processing unit 2032 Page memory 2033 Encoding processing unit 204 Print spooler 205 Engine monitoring unit 206 Application software 210 Keyboard 211 Mouse 212 Interface 220 Display monitor

Claims (23)

[Claims] 1. An information processing apparatus for supplying image information to a printing apparatus, comprising: monitoring means for monitoring a state of the printing apparatus; and a plurality of encoding methods different from each other based on the state of the printing apparatus. , Select one encoding method,
An information processing apparatus, comprising: an encoding unit that encodes image information according to a selected encoding method; and a transfer unit that transfers the encoded image information to the printing device. 2. The information processing apparatus according to claim 1, wherein said encoding means determines an encoding method for each predetermined unit. 3. The information processing apparatus according to claim 2, wherein the predetermined unit is a page unit, a frame unit, or a band unit. 4. The encoding means according to claim 1, wherein:
4. The method according to claim 1, wherein a first coding method having a relatively high processing speed or a second coding method having a relatively high coding efficiency can be selected. 5. An information processing apparatus according to claim 1. 5. The information processing method according to claim 4, wherein the first coding method has a relatively low coding efficiency, and the second coding method has a relatively low processing speed. apparatus. 6. The encoding method according to claim 1, wherein said encoding unit has a relatively high processing speed for a predetermined unit of image information to be encoded first when the operation of said printing apparatus is paused. The information processing apparatus according to claim 1, wherein the information is encoded by: 7. The information processing apparatus according to claim 6, wherein the encoding unit encodes the subsequent image information using an encoding method having relatively high encoding efficiency. 8. An information processing method for supplying image information to a printing device, comprising: a monitoring step of monitoring a status of the printing device; and a plurality of encoding methods different from each other based on the status of the printing device. , Select one encoding method,
An information processing method, comprising: an encoding step of encoding image information according to a selected encoding method; and a transferring step of transferring the encoded image information to the printing apparatus. 9. The encoding method according to claim 8, wherein an encoding method is determined for each predetermined unit.
An information processing method according to claim 1. 10. The information processing method according to claim 9, wherein the predetermined unit is a page unit, a frame unit, or a band unit. 11. In the encoding step, a first encoding method having a relatively high processing speed or a second encoding method having a relatively high encoding efficiency can be selected as an encoding method. The information processing method according to claim 8, wherein: 12. The information processing method according to claim 11, wherein the first coding method has a relatively low coding efficiency, and the second coding method has a relatively low processing speed. Method. 13. In the encoding step, when the operation of the printing apparatus is paused, an encoding method in which a processing speed is relatively high for a predetermined unit of image information to be encoded first. The information processing method according to claim 8, wherein encoding is performed by: 14. The information processing method according to claim 13, wherein, in the encoding step, subsequent image information is encoded by an encoding method having relatively high encoding efficiency. 15. An information processing apparatus for supplying image information to a printing apparatus, comprising: a first encoding system having a relatively high processing speed or a second encoding system having a relatively high encoding efficiency. Encoding means for encoding information; andtransfer means for transmitting the encoded image information to the printing apparatus, wherein the encoding means firstly operates when the operation of the printing apparatus is suspended. An information processing apparatus characterized in that image information of a predetermined unit to be encoded is encoded by the first method. 16. The information processing apparatus according to claim 2, wherein the encoding unit encodes subsequent image information by the second method. 17. The information processing apparatus according to claim 15, wherein the predetermined unit is a page unit, a frame unit, or a band unit. 18. An information processing method for supplying image information to a printing apparatus, comprising: a first encoding method having a relatively high processing speed or a second encoding method having a relatively high encoding efficiency. An encoding step of encoding information, and a transfer step of transmitting the encoded image information to the printing apparatus.In the encoding step, when the operation of the printing apparatus is paused, An information processing method, wherein image information of a predetermined unit to be encoded is encoded by the first method. 19. The information processing method according to claim 18, wherein, in the encoding step, subsequent image information is encoded by the second method. 20. The information processing method according to claim 18, wherein the predetermined unit is a page unit, a frame unit, or a band unit. 21. A printing system, comprising: an information processing apparatus that performs communication via a communication line; and a printing apparatus, wherein the information processing apparatus includes: a monitoring unit that monitors a state of the printing apparatus; Based on the state, select any one of a plurality of encoding schemes different from each other,
Encoding means for encoding the image information according to the selected encoding method; and transfer means for transferring the encoded image information to the printing device, wherein the printing device is configured to transmit the image transferred from the information processing device. A printing system comprising: decoding means for decoding information; and output means for outputting an image on a recording medium based on the combined image information. 22. A memory medium storing a control program code of an information processing apparatus for supplying image information to a printing apparatus, wherein the code is for a monitoring step of monitoring the state of the printing apparatus, and And selecting any one of a plurality of encoding schemes different from each other,
A memory medium, comprising: a code of an encoding step for encoding image information according to a selected encoding method; and a code of a transfer step of transferring the encoded image information to the printing apparatus. 23. A memory medium storing a control program code of an information processing apparatus for supplying image information to a printing apparatus, wherein the first encoding method has a relatively high processing speed or has a relatively low coding efficiency. A code of an encoding step of encoding the image information according to a high second encoding method, and a code of a transfer step of transferring the encoded image information to the printing apparatus. A memory medium characterized in that, when the operation of the apparatus is suspended, image information of a predetermined unit to be encoded first is encoded by the first method.