JP2001142659A - Device and method for information processing and printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a high quality output even in a high-speed printer engine without bringing about a cost increase. SOLUTION: This information processor has a dividing means which divides the image information on one page into a plurality of bands, a compressing means which compresses the image information in a band unit to be transferred to a printing controller, and a transfer controlling means which controls the image information on the band unit compressed by the compressing means so as to be transferred to the printing controller.

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 for transferring image information to a print control apparatus via an interface, an information processing method in the information processing apparatus, and an interface between the information processing apparatus and the print control apparatus. The present invention relates to a printing method in a printing system connected via a printer.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional printing system.

That is, a conventional printing system includes a host computer 101 for generating print information and image information,
It comprises a printer 102 connected to the host computer 101 via a predetermined interface such as a Centronics interface. Further, the printer 102 includes a printer controller 103 for controlling print information and image information sent from the host computer 101, and a printer engine 10 for controlling electrophotographic processes such as charging, exposure, development, transfer, fixing, and paper conveyance.
The printer engine 104 and the printer controller 103 can communicate with each other via a video interface.

In the above printing system, when the printer controller 103 receives a print start command as image information and print information from the host computer 101,
The print start command and a video signal as image information are sent to the printer engine 104.

The printer engine 104 controls the electrophotographic process and performs a printing process based on the video signal. Also, the printer controller 103
The printer engine 104 detects the status of the printer 102 and sends it to the host computer 101 as print environment information.

[0006]

However, in the conventional printing system, the transfer speed of the image information from the host computer 101 to the printer controller 103 is reduced from the printer controller 103 to the printer engine 10.
4, the image information transmission speed from the host computer 101 to the printer controller 103 is higher than the image information transmission speed to the printer engine 103. If the speed is lower than the speed, that is, it cannot cope with a high-speed printer engine. In other words, with the recent demand for higher speed, higher resolution, and lower cost of printers, the conventional printing system has a problem that the speed of the printer engine is limited in performing print output required by a user. there were.

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem, and an information processing apparatus, an information processing method, and an information processing method that guarantee high-quality output even in a high-speed printer engine without increasing costs. It is intended to provide a printing method.

[0008]

According to the present invention, in order to solve the above-mentioned problems, one page of image information is divided into a plurality of bands, and the image information of each band is compressed and transferred in band units.

That is, the information processing apparatus according to the present invention comprises:
A dividing unit that divides the image information of one page into a plurality of bands; a compressing unit that compresses the image information in band units transferred to the print control apparatus; and a unit that divides the image information in band units compressed by the compressing unit. Transfer control means for controlling transfer to the print control device.

The information processing method according to the present invention further comprises a dividing step of dividing one page of image information into a plurality of bands, a compressing step of compressing band-wise image information transferred to the print control device, And a transfer control step of controlling transfer of the image information in band units compressed by the compression step to the print control apparatus.

Further, a printing method according to the present invention is a printing method in a printing system in which an information processing apparatus and a printing control apparatus are connected via an interface, wherein one page of image information generated by the information processing apparatus is provided. Dividing the image into a plurality of bands, and a compression step of compressing the image information of each band transferred to the print control device,
The compressed band-based image information transferred to the print control device is decompressed and, before being sent to the printing unit, the compressed next band-based image information is transmitted to the print control device. Transmission control means for controlling, and print control for expanding the compressed band-wise image information transferred to the printing control device and receiving the compressed next band-wise image information while sending the same to the printing unit. And a step.

[0012]

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

FIG. 1 is a block diagram showing an embodiment of a printing system according to the present invention. The printing system includes a host computer 1 for generating print information and image information, and a predetermined interface such as a Centronics interface. , And a laser beam printer 2 connected to the host computer 1 via the printer.

The host computer 1 includes an application processing unit 3 for processing a predetermined application program, and a print information analysis unit 4 for analyzing print information sent from the application processing unit 3 and generating image information.
A compressed image information generation unit 5 for generating compressed image information from the image information generated by the print information analysis unit 4, and a print command for inputting the compressed image information and a print command from the print information analysis unit 4 A generation unit 6, a printing environment detection unit 7 for detecting printing environment information sent from the laser beam printer 2, and a screen display control unit 8 to which the printing environment detected by the printing environment detection unit 7 is input. It has.

The laser beam printer 2 includes a printer controller 9 for transmitting and receiving various information to and from the host computer 1, and a printer engine 10 as a print processing unit. The printer engine 10 is specifically composed of known components that execute a series of electrophotographic processes, such as a recording medium transport mechanism, a semiconductor laser unit, a photosensitive drum, a developing unit, a fixing unit, a cleaning unit, and a separating unit. ing.

The printer controller 9 receives a compressed image information and the like from the host computer 1 and sends the printing environment information in the laser beam printer 2 to the host computer 1. A RAM 12 for storing decompressed image information created based on the image information;
A printer engine controller 13 for controlling the printer engine 10 based on the decompressed image information stored in the M12.

In the printing system configured as described above, the print information analyzer 4, print command generator 6, and print environment detector 7 built in the host computer 1 are activated at the same time as the host computer 1 is activated. When the user executes the print processing while using the application, the application processing unit 3 sends the print information to the print information analysis unit 4, and the print information analysis unit 4 generates image information and a print command from the print information. , The compressed image information generating unit 5 and the print instruction generating unit 6 respectively.
To send to. Next, the compressed image information generating unit 5 converts the image information into dot information to generate compressed image information, and synchronizes the compressed image information with a laser beam printer in synchronization with a print start command (print command) in the print command generating unit 6. Send to 2 side.

In the laser beam printer 2, the print start command sent from the host computer 1 is sent to the printer engine 10 via the print information control unit 11 and the printer engine control unit 13 built in the printer controller 9. You. On the other hand, the print information control unit 11
The compressed image information input to the RAM 12 is transferred to the RAM 12 and decompressed based on compression method information described later, and the decompressed image information is also stored in the RAM 12. When the printer engine control unit 13 detects the information transfer enabled notification from the printer engine 10, the decompressed image information stored in the RAM 12 is transferred to the printer engine 10 via the printer engine control unit 13 and a predetermined printing job is executed. Is done.

The printing environment of the printer engine 10 is as follows.
The data is transferred to the print environment detection unit 7 of the host computer 1 via the printer engine control unit 13 and the print information control unit 11. When the printing environment detecting unit 7 detects the printing environment information, the printing environment detecting unit 7 notifies the printing environment to the print information analyzing unit 4 and the screen display control unit 8 and performs predetermined control.

As shown in FIG. 2, the compressed image information generating section 5 specifically includes an image expanding section 14 for expanding image information sent from the print information analyzing section 4 for each band. A band buffer 15 that stores the image information of one page that has been expanded and divided into a plurality of bands, and a plurality of compression methods for converting the image information stored in the band buffer 15 into compressed image information. The image processing apparatus includes a compression method selection unit 16 that selects a compression method, and a compression processing unit 17 that executes the specific compression method selected by the compression method selection unit 16 to compress image information. That is, when image information from the print information analysis unit 4 is input to the image development processing unit 14, the image development processing unit 14 generates image information for each page. (The first band, the second band,..., The Nth band) and stored in the band buffer 15. Here, it is not always necessary to provide the band buffer 15 with the capacity of the number of bands of the image information sent for each page. For example, the band buffer 15 having a storage capacity of a band smaller than the number of bands is provided. It is also preferable to use the buffer 15 in a ring format.

Next, the compression method selection section 16 selects and determines what compression method is used to compress the image information stored in the band buffer 15. That is, the compression processing section 17 stores a plurality of compression schemes (a first compression scheme, a second compression scheme,..., An N-th compression scheme). Select a specific compression method from the compression methods. That is, the compression method selection unit 16
Are assigned in advance a plurality of compression schemes of the compression processing unit 17, and the compression scheme selection unit 1
6, the compression method is selected in the order of, for example, the first compression method and the second compression method. In this case, depending on the content of the image information, for example, it is preferable to assign a selection order so that the image information is selected from the second compression method and the character information is selected from the third compression method. . As a result, the compression processing unit 17 compresses the image information based on the selected compression method to generate compressed image information, and adds 1-byte compression method information to the head of the compressed image information. 6 is transferred to the laser beam printer 2 side.

The print information control section 11 of the laser beam printer 2 stores a reception information control section 18 for receiving compressed image information from the host computer 1 and compression method information located at the head of the compressed image information. Compression method storage buffer 19 and a plurality of decompression methods (first decompression method, second decompression method,
, An N-th decompression method, a decompression method selection unit 20 for selecting a specific decompression method, and the decompression method selection unit 2
And a decompression processing unit 21 for performing a decompression process using the specific decompression method selected at 0. That is, the decompression processing unit 21 includes the plurality of decompression methods, and the decompression method selection unit 20 selects a specific decompression method from the plurality based on the compression method information stored in the compression method storage buffer 19. select. That is, the first decompression method, the second decompression method,..., The N-th decompression method of the decompression processing unit 21 are the first compression method, the second compression method,. , N-th compression method, and the decompression method is selected by the decompression method selection unit 20 based on the compression method information added to the head of the compressed image information. The information is decompressed.

The RAM 12 has a reception information control unit 18.
And a decompressed image information storage buffer 23 that stores decompressed image information decompressed by the decompression processing unit 21.

The print information control unit 11 thus configured
In the above, of the compressed image information to which the compression method information sent from the host computer 1 is added, the compression method information is sent from the reception information control unit 18 to the compression method storage buffer 19, and other than the compression method information. The compressed image information is sent from the reception information control unit 18 to the compressed image information storage buffer 22, and stored in the compression method storage buffer 19 and the compressed image information storage buffer 22, respectively. And
After the reception of the compressed image information for one band relating to the compression method information is completed, the decompression method selection unit 20 selects the decompression method from the information stored in the compression method storage buffer 19 (compression method information), and compresses the data in the RAM 12. The compressed image information stored in the image information storage buffer 22 is sent to the decompression processing unit 21 via the decompression method selection unit 20. And
The decompression processing unit 21 decompresses the compressed image information according to the decompression method selected and specified by the decompression method selection unit 20, generates a decompressed compressed image, and sends out the generated decompressed image information to the decompressed image information storage buffer 23. You.

FIG. 3 is a flowchart of a compression control procedure executed by the host computer. Incidentally, the host computer 1 recognizes in advance the transmission time Tp (video signal speed) of the expanded image information from the printer controller 9 in the laser beam printer 2 to the printer engine 10,
In addition, it is assumed that the transmission time Tp of the decompressed image information is a short high-speed printer, and for convenience of description, the compression method can be changed up to twice.

In step S 1, the image information sent from the print information analyzer 4 is received by the image expansion processor 14 of the compressed image information generator 5. Next, the image development processing unit 14 divides the image information for each band to generate image information and stores it in the band buffer 15 (step S2). In the following step S3, the compression method selection unit 16 selects a specific compression method from among a plurality of compression methods,
In step 7, image information is compressed using the selected specific compression method (step S4).

Next, in the print information analysis section 4, the transfer time Th of the compressed image information from the host computer 1 to the laser beam printer 2 and the transmission time Tp of the expanded image information from the printer controller 9 to the printer engine 10
Is calculated (step S5). That is, the transfer time Th is calculated from the image information for one band stored in the band buffer 15, and the transmission time Tp is calculated from the expanded image information for one band. In this case, it is preferable to increase the transmission time Tp of the expanded image information in consideration of the expansion time of the compressed image information.

Next, the process proceeds to step S6, and it is determined whether or not the transfer time Th of the compressed image information is longer than the transmission time Tp of the expanded image information. Then, the transfer time T of the compressed image information
If h is longer than the transmission time Tp of the expanded image information, it is determined whether or not the compression of the image information is the first time in the same band (step S7), and if the compression of the image information is the first time, the compression method is changed. And returns to step S4. That is, for example, the compression method is changed from the first compression method to the second compression method, and the process returns to step S4 to compress the image information again using the changed compression method. Here, when the compression rate is lower than the previous compression scheme, the information of the previous compression scheme is adopted, and when the compression rate is opposite, the information of the current compression scheme is adopted.

If the transfer time Th of the compressed image information is shorter than the transmission time Tp of the expanded image information in step S6, or if it is determined that the image information compression is the second time in the same band, the compressed image information One byte of compression method information is added to the beginning (step S9). Thereafter, the print command generation unit 6 synchronizes with the print start command sent from the print information analysis unit 4 and adds the compression method information to the compressed image information. Is transferred to the laser beam printer 2 (step S10), and the process ends. Such processing is performed for all bands until image information for one page is processed.

FIG. 4 is a flowchart of a decompression control procedure executed by the print information control unit 11.

The reception information control unit 18 of the print information control unit 11 receives the compressed image information to which the compression method information has been added from the host computer 1 (step S11). The first byte of the received compressed image information has the compression method information added thereto as described above, and stores the compression method information in the compression method storage buffer 19 (step S1).
2). Next, the compressed image information other than the compression method information is stored in the compressed image information storage buffer 22 of the RAM 12 (Step S13), and it is determined whether the reception of the compressed image information for one band is completed (Step S14). . If the determination result is negative (No), the process returns to step S14 to continue the information reception, and if the reception of the compressed image information for one band is completed, the decompression method selection unit 20 stores the information in the compression method storage buffer 19. A specific decompression method is selected based on the obtained compression method information (step S15). Next, the compressed image information stored in the compressed image information storage buffer 22 is sent to the decompression processing unit 21 via the decompression method selection unit 20 (step S16), and the decompression processing unit 21 uses the selected specific decompression method. To expand the compressed image information (step S17).
2 (step S18), and the process ends.

The above processing is performed for all bands of the compressed image information to which the compression method information is added for the compressed image information of one page.

The present invention is not limited to the above embodiment. In the above embodiment, the selection of the compression method corresponds to the high-speed printer engine.
Although the example in which the compression method is selected twice, that is, two times in total, has been described, it is also possible to change the number of times the compression method is selected according to the speed of the printer engine 10. That is, by changing and specifying the number of compression methods in step S7 in FIG. 3 according to the printer engine 10, the same processing routine can be used from the low-speed printer engine to the high-speed printer engine.

Further, when the amount of information at the time of recompression is larger than the amount of information at the time of previous compression, the information at the time of previous compression is described as being adopted. Where possible, recompressed information can be employed.

Further, it is preferable that the compression method is switched by the compressed image information generation unit 5 by adding information of the application processing unit 3 to the image information sent from the print information analysis unit 4.

[0036]

As described above in detail, according to the present invention, 1
Since the image information of the page is divided into a plurality of bands, and the image information in the band unit is compressed and transferred in the band unit, the information processing apparatus transmits the compressed image information in the band unit transferred to the print control apparatus. Can be transmitted to the printing unit while the image information of the next compressed band is transmitted to the printing unit while the compressed image information is transmitted to the printing unit. While the image information in the band unit is decompressed and transmitted to the printing unit, the compressed image information in the next band unit can be received.

As a result, even when a high-speed printer engine is used, the cost does not increase,
A printing system that can guarantee high-quality output can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a printing system according to the present invention.

FIG. 2 is a block diagram showing details of a main part of FIG. 1;

FIG. 3 is a flowchart of a compression control procedure.

FIG. 4 is a flowchart of a decompression control procedure.

FIG. 5 is a block diagram schematically showing a conventional printing system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 host computer (information processing device) 4 print information analysis unit (generation unit) 6 print instruction generation unit (transfer control unit) 9 printer controller (print control device) 15 band buffer (division unit, storage unit) 16 compression method selection unit (Selection means) 17 Compression processing unit (compression means)

Claims (16)

[Claims] 1. An information processing apparatus for transferring image information to a print control device via an interface, comprising: a dividing unit for dividing one page of image information into a plurality of bands; and a band transferred to the print control device. An information processing apparatus comprising: compression means for compressing image information in units; and transfer control means for controlling transfer of the image information in band units compressed by the compression means to the print control apparatus. 2. A method according to claim 1, further comprising generating means for generating image information based on print information from an application program, wherein said dividing means divides the image information of one page generated by said generating means into a plurality of bands. The information processing apparatus according to claim 1, wherein: 3. The image processing apparatus according to claim 1, further comprising a selection unit configured to select a compression method when compressing the image information in band units, wherein the compression unit converts the image information in band units according to the compression method selected by the selection unit. 3. The information processing apparatus according to claim 1, wherein the information is compressed. 4. The image processing apparatus according to claim 1, further comprising a selection unit that selects a compression method when compressing the image information in band units, wherein the transfer control unit converts information indicating the compression method selected by the selection unit into compressed information. 4. The information processing apparatus according to claim 1, wherein the information is added to the image information in band units. 5. The image processing apparatus according to claim 1, further comprising storage means for storing the image information in band units.
An information processing device according to any one of the above. 6. The print control apparatus according to claim 1, wherein the transfer control unit controls to transfer the compressed image information in band units to the print control device in band units. An information processing apparatus according to claim 1. 7. An information processing method for transferring image information from an information processing device to a print control device via an interface, comprising: a dividing step of dividing one page of image information into a plurality of bands; A compression step of compressing the image information in band units to be transferred, and a transfer control step of controlling to transfer the image information in band units compressed in the compression step to the print control device. Information processing method. 8. A generating step of generating image information based on print information from an application program executed in the information processing apparatus, wherein the dividing step includes the step of generating one page of image information generated by the generating step. The information processing method according to claim 7, wherein is divided into a plurality of bands. 9. The image processing method according to claim 1, further comprising a selecting step of selecting a compression method for compressing the image information in band units, wherein the compressing step compresses the image information in band units according to the compression method selected in the selecting step. 9. The information processing method according to claim 7, wherein: 10. The image processing method according to claim 1, further comprising a selecting step of selecting a compression method when compressing the image information in band units, wherein the transfer control step includes: information indicating the compression method selected in the selecting step; 10. The information processing method according to claim 7, wherein the information is added to image information in band units. 11. The transfer control step according to claim 7, wherein the control is performed such that the compressed image information in band units is transferred to the print control device in band units. An information processing method according to claim 1. 12. A printing method in a printing system in which an information processing device and a printing control device are connected via an interface, wherein one page of image information generated by the information processing device is divided into a plurality of bands. A dividing step, a compressing step of compressing the band-based image information transferred to the print control apparatus, and the compressed band-based image information transferred to the print control apparatus are decompressed and transmitted to the printing unit. Before transmitting, the transmission control means for controlling transmission of the next compressed image information in band units to the print control device, and expanding the compressed image information in band units transferred to the print control device. A print control step of receiving compressed next image information in band units while transmitting the image information to the printing unit. 13. A method for generating image information based on print information from an application program executed by the information processing apparatus, wherein the dividing step includes the step of generating one page of image information generated by the step unit. 14. The printing method according to claim 12, wherein is divided into a plurality of bands. 14. The image processing method according to claim 1, further comprising a selecting step of selecting a compression method when compressing the image information in band units, wherein the compressing step compresses the image information in band units using the compression method selected in the selecting step. 14. The printing method according to claim 12, wherein the printing is performed. 15. The image processing apparatus according to claim 15, further comprising a selection step of selecting a compression method when compressing the image information in band units, wherein the transfer control step converts the information indicating the compression method selected by the selection step into the compressed information. The printing method according to any one of claims 12 to 14, wherein the printing method is added to image information in band units. 16. The print control apparatus according to claim 12, wherein the transfer control step controls to transfer the compressed image information in band units to the print control device in band units. Printing method described in 1.