JPH10124269A - Image output system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time for the compression, transfer, expansion, etc., of print data and speedily obtain a print result by converting bit map data on a host device side according to the number of gradations of print information. SOLUTION: When a host computer 1 transfers a printer information transfer command to a color laser printer 2, the printer 2 transfers the number of gradations corresponding to its resolution to the computer 1. The computer 1 generates print data described in PDL, converts bit map data in it according to the number of gradations of the printer information, and compressed and transfers the data to the printer 2. Then the printer 2 interprets the command part of the print data and expands it in a page memory, and also performs its image expansion in detail since the bit map data are already converted according to the number of gradations, thereby putting them one over the other. Then the printer 2 performs image output according to those image data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image output system for transferring print data from a host device to an image output device and outputting an image based on the print data by the image output device.

[0002]

2. Description of the Related Art This type of image output system is configured by connecting a host device 101 and an image output device 102 via a communication line 103 as shown in FIG. The host device 101 is configured by connecting an input device such as a display device 105 and a keyboard 106 to a host device main body 104.

When printing the print data created by the host device 101 by an image output device, control as shown in FIG. 7 is performed. That is, first, the host device 101 starts up software for creating print data and performs initial settings such as setting of initial values. Subsequently, for example, the keyboard 106 is viewed while viewing the display screen of the display device 105.
For example, a graphic or character input by the user is created as print data, the print data is subjected to a predetermined compression process, and is transferred to the image output device 102.

Here, the print data created by the host apparatus 101 is PDL (Page Description Language).
Some are described in e). That is, the print data is composed of a command portion composed of words (languages) representing figures and texts such as circles and straight lines, and bitmap data representing information such as the size and position of figures and characters following the command portion. And a part.

On the other hand, the image output device 102 is constituted by, for example, a laser printer, an ink jet printer, a thermal printer or the like, and performs control as shown in FIG. That is, the image output apparatus 102 first waits for reception of print data from the host apparatus 101. Subsequently, when print data is transferred from the host device 101 via the communication line, the print data is received and temporarily stored in the RAM. Then, while interpreting the words of the command part in the received print data and developing the image on the page memory, the bit map data part is converted according to a predetermined number of gradations according to the resolution of the image forming apparatus 102. These are developed on the page memory and superimposed. Then, the data on the page memory is output as an image.

[0006]

In such an image output system, print data described in PDL created by the host device 101 is composed of figures and characters such as circles and straight lines in order to reduce the amount of data. It is designed to be expressed by commands with a small amount of data. However, since information such as the size and position of figures and characters is represented by bitmap data having a large data amount, the total data amount is occupied by the bitmap data, and is assumed to be large by the bitmap data. Become.

Therefore, in the host device 101, it takes time to compress such print data, and it takes time to transfer the print data to the image output device 102. On the other hand, there is a problem that it takes time for the image forming apparatus 102 to decompress the received print data, and it takes a long time from when the host apparatus 101 creates the print data to when the image forming apparatus 102 outputs the image. If the print data is color data such as 256 gradations or 24-bit full color, the data amount becomes particularly large, and it takes a very long time to output an image.

Accordingly, an object of the present invention is to provide an image output system capable of shortening the time for compressing, transferring, decompressing print data, etc., and quickly obtaining a print output result.

[0009]

According to the first aspect of the present invention, print data is transferred from a host device to an image output device connected to the host device, and an image is output by the image output device based on the print data. In the image output system, the host device instructs the image output device to transfer print information including information on the number of gradations, and print information receiving means for receiving print information from the image output device; Print data creating means for creating print data including data, and the number of gradations of the image output device based on print information received by the print information receiving means from bitmap data of the print data created by the print data creating means. Bitmap data conversion means for converting the bitmap data according to the bitmap data converted by the bitmap data conversion means. Print data transfer means for transferring data to the image output device, the image output device, when receiving a print information transfer command from the host device, print information transfer means for transferring print information to the host device according to the command, A print data receiving means for receiving print data from a host device; and a data developing means for decoding a command of the print data received by the print data receiving means and developing the command on a memory together with bitmap data. It is.

According to a second aspect of the present invention, the host device includes a data compression unit for compressing print data including the bitmap data converted by the bitmap data conversion unit before transferring the print data to the image output device. 2. The image output system according to claim 1, wherein the output device includes a data decompression unit that decompresses the print data received from the host device by the print data reception unit before the data decompression unit decompresses the data.

In the present invention having such a configuration, the host apparatus instructs the image forming apparatus to transfer print information including information on the number of gradations of the image forming apparatus, and the image forming apparatus follows the instruction. Transfer the print information to the host device. Then, the host device receives the print information, converts the bitmap data of the print data according to the number of gradations included in the print information, thereby reducing the data amount of the print data, The print data is compressed and transferred to the image forming apparatus. Then, the image forming apparatus receives the print data from the host device, decompresses the data, decodes the command part of the print data, expands the command portion with the bitmap data on the memory, and stores the data in the memory on the memory. The printout is performed based on the printout.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of an image output system according to the present invention, wherein 1 is a host computer as a host device, and 2 is a color laser printer as an image output device. The host computer 1 and the color laser printer 2 are mutually connected via a communication line 3. The host computer 1 is configured by connecting an input device such as a display device 5 and a keyboard 6 to a host computer main body 4.

FIG. 2 is a block diagram showing the configuration of the host computer 1. Reference numeral 11 denotes a CP constituting the control unit main body.
U (Central Processing Unit), 12 is a ROM (Read Only Memory) storing program data and the like for the CPU 11 to control each unit, 13 is a RAM provided with a memory used for data processing ( A random access memory (14), an I / F (interface) to which the color laser printer 2 is connected via the communication line 3;
Is a display controller that controls the display device 5, 16 is a keyboard controller that controls a keyboard, and 17 is a hard disk device controller that controls a hard disk device 18 in which software and various data are stored.

CPU 11 and ROM 12, RAM 1
3, I / F 14, display controller 15, keyboard controller 16, hard disk device controller 17
Are electrically connected by a bus line 19 such as a data bus, an address bus, and a control bus.

FIG. 3 is a sectional view showing the structure of the color laser printer. Reference numerals 221 to 224 denote four printing stations arranged continuously on an endless belt-shaped paper transport belt 21 stretched inside the apparatus main body. is there. Each of the printing stations 221 to 224 includes a charger 2 around the photosensitive drum 23.
4. Exposure device 25, developing device 26, drum cleaner 2
7. Discharge lamp 28 is disposed opposite to the photosensitive drum 23
The transfer roller 29 is disposed to face the paper transfer belt 21 via the paper transport belt 21.

The developing devices 26 of the printing stations 221 to 223 are respectively yellow (Y), magenta (M),
The developing device 26 of the printing station 224 stores the cyan (C) color toner, and supplies the toner to the photosensitive drum 23 by the developing roller 30 rotatably provided at the lower portion, storing the black (K) toner. It has become.

A belt charger 31 is disposed at a position where the paper transport belt 21 starts to be transported, and a tension roller 32 that applies a predetermined tension to the paper transport belt 21 is disposed. The paper transport belt 21 is made of a conductive material, and its surface is covered with an insulating layer. Then, it is stretched over a pair of guide rollers 34 and 35 so that the conductive material contacts.

Below the paper transport belt 21, there is provided a paper feeder 39 in which recording papers 38 are stacked and housed in a detachable manner. On the upper side of the paper feeding device 39, the recording paper 38
Paper feed roller for picking up the recording paper 3
8 and the like are provided.

In the vicinity of one guide roller 34, a transport path 33 for guiding a recording sheet 38 from a sheet feeding device 39 to the end of the sheet transport belt 21 is provided. Further, a fixing device 40 is arranged outside the other guide roller 35 in close proximity.

In this apparatus, a recording paper 38 fed from a paper feeding device 39 is transferred to a paper transport belt 2 by a belt charger 31.
Then, the yellow image is transferred at the printing station 221, the magenta image is transferred at the printing station 222, and the cyan image is transferred at the printing station 223. The sheet is ejected by the fixing unit 40 after being thermally fixed.
The paper is discharged to

FIG. 4 is a block diagram showing the circuit configuration of the color laser printer shown in FIG. 3. Reference numeral 45 denotes a CPU (central processing unit) constituting a control unit main body;
Is a ROM (Read Only Memory) storing program data and the like for controlling each unit, and 47 is an R provided with a page memory and the like for storing image-developed print data.
AM (random access memory), 48 is I / O
An (input / output) port 49 is an I / F (interface). CPU 45 and ROM 46, RAM 47, I /
The O port 48 and the I / F 49 are electrically connected by a bus line 51.

The I / O port 48 is connected to the printing stations 221 to 224, the fixing device 40, various sensors 52 such as a sensor for detecting a jam of the recording paper 38, An operation panel 53 for performing various operations such as correction of the image is connected. In addition, I / F4
9 is connected to the host computer 1 via a communication line.

The exposure device 5 of each of the printing stations 221 to 224 irradiates a laser beam to the photosensitive drum 23 based on image data obtained by developing print data from the host computer 1 on a page memory to form an electrostatic latent image. I do.

Hereinafter, when an image is formed using the image forming system having the above-described configuration, the host computer 1 is configured as shown in FIG.
And the color laser printer performs the control as shown in FIG.

That is, the host computer 1 is configured as shown in FIG.
As shown in (1), first, in ST (step) 1, the software for creating print data is started and initial settings such as setting of initial values are performed. In the present invention, at the time of this initial setting, the host computer 1 uses the number of tones according to the resolution of the color laser printer 2 as printer information (print information).
To transmit a printer information transfer command for transfer via the communication line 3. Then, the printer waits for printer information in ST2.

At this time, if it is determined that the printer information has been received from the color laser printer 2, the printer information received in ST3 is stored in the RAM 13 (print information receiving means). Subsequently, in ST4, figures, characters, and the like input by the keyboard 6 or the like are created as print data while viewing the display screen of the display device 5, for example.

Here, the print data created by the host computer 1 is a PDL (Page Description Language).
). This print data is composed of a command part composed of words (language) representing figures and texts such as circles and straight lines, and bitmap data that is information such as figures and characters following the command part, such as the size and position of characters. And a part.

Next, in ST5, the bitmap data portion of the print data is converted in accordance with the number of gradations from the RAM 13 (bitmap data conversion means). At this point, the data amount of the entire print data is reduced. Then, S
At T6, the print data is subjected to compression processing, and is transferred to the color laser printer 2 via the communication line 3 at ST7 (print data transfer means).

On the other hand, the color laser printer 2 first determines whether or not a printer information transfer command has been received from the host computer 1 in ST11 as shown in FIG. At this time, when it is determined that the printer information command has been received, the color laser printer 2 is determined in ST12.
Is transferred to the host computer 1 as printer information.

If it is determined in ST11 that the printer information transfer command has not been received from the host computer 1, it is determined whether or not print data has been received from the host computer 1 in ST13. At this time, if it is determined that the print data has not been received, the process returns to ST11. If it is determined that the print data has been received, the process returns to ST11.
At 14, the print data is temporarily stored in the RAM 13 (print data receiving means).

Subsequently, in ST15, the print data from the RAM 13 is expanded, and in ST16, the words in the command section in the print data are interpreted and developed into an image on the page memory. The bitmap data converted in accordance with (1) is also developed on the page memory and superimposed (data developing means). The exposure device 25 is controlled based on the image data on the page memory to control the photosensitive drum 23.
Is irradiated with a laser beam to form an electrostatic latent image. This is transferred to a recording paper or the like to perform image output.

In the embodiment of the present invention having such a configuration, when the host computer 1 transfers a printer information transfer command to the color laser printer 2, the color laser printer 2 executes a process according to the resolution of the color laser printer 2. The tones are transferred to the host computer 1 as printer information.

The host computer 1 creates print data described in PDL, and converts bitmap data in the print data according to the number of gradations of printer information received from the color laser printer 2. This allows
The data amount of the entire print data is significantly reduced. Specifically, for example, if the print data is composed of 24-bit full color and the number of gradations is binary, the data amount of the print data is reduced to about 1/24. This is based on the assumption that most of print data of photographs and pictures is bitmap data and the entire data amount is large. Therefore, if the bitmap data can be reduced, the entire print data can be reduced.

The print data is subjected to a compression process in a state where the print data is converted in accordance with the number of gradations of the color laser printer 2 and transferred to the color laser printer 2. Then, the color laser printer 2 interprets the words of the command part of the print data and develops the image on the page memory, and the bit map data has already been converted by the host computer 1 according to the number of gradations. The image is developed on the page memory as it is, and these are superimposed. The color laser printer 2 outputs an image based on the image data on the page memory.

As described above, the host computer 1 previously receives the number of gradations from the color laser printer 2 as printer information, and converts bitmap data having a large data amount among the print data in accordance with the number of gradations. Since the converted print data is compressed and transferred to the color laser printer, the print data can be compressed and transferred with the data amount reduced. As a result, it is possible to reduce the time required for compressing and transferring the print data and for expanding the data on the color laser printer side. Therefore, a print output result can be obtained quickly.

In the embodiment of the present invention, a color laser printer is used as an image output device. However, the present invention is not limited to this, and a monochrome laser printer is used as an image output device. Or a printer using an inkjet printer, a thermal printer, or the like.

[0037]

As described above in detail, according to the present invention, print data can be reduced by converting bitmap data on the host device side. As a result, the time for compressing, transferring, and expanding the print data can be reduced, and the result of print output can be obtained. Further, by compressing / expanding the print data, the time until the print output can be further reduced. As a result, a printing result can be obtained quickly even in printing including a large amount of bitmap data.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an image output system according to an embodiment of the present invention.

FIG. 2 is an exemplary block diagram showing the configuration of the host computer shown in FIG.

FIG. 3 is a sectional view showing the configuration of the color laser printer shown in FIG.

FIG. 4 is a block diagram showing a configuration of a control unit of the color laser printer shown in FIG.

FIG. 5 is a flowchart of control performed by a CPU of the host computer shown in FIG. 2;

FIG. 6 is a flowchart of control performed by a CPU of the color laser printer shown in FIG. 4;

FIG. 7 is a diagram showing a configuration of a conventional image output system.

FIG. 8 is a flowchart of control performed by a CPU of the host computer shown in FIG. 7;

FIG. 9 is a flowchart of control performed by a CPU of the color laser printer shown in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Host computer (host apparatus) 2 ... Color laser printer (image forming apparatus) 3 ... Communication line 11 ... CPU of host computer 45 ... CPU of color laser printer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sakae Shiida 570 Ono-cho, Oni-cho, Taga-gun, Shizuoka Prefecture Inside the Tech Ono Works Co., Ltd. In the Ohito Office

Claims (2)

[Claims] 1. An image output system for transferring print data from a host device to an image output device connected to the host device, and outputting an image on the image output device based on the print data, wherein the host device comprises: A print information receiving unit for instructing the image output device to transfer print information including information on the number of gradations and receiving print information from the image output device, and creating print data including commands and bitmap data. A print data creation unit, and a bit for converting bitmap data of the print data created by the print data creation unit in accordance with the number of tones of the image output device based on the print information received by the print information reception unit. Map data conversion means, and print data including the bitmap data converted by the bitmap data conversion means. A print data transfer unit for transferring the print information to the image output device; a print information transfer unit for transferring the print information to the host device in accordance with the print information transfer command from the host device when receiving the print information transfer command from the host device; Print data receiving means for receiving print data from the host device, and data developing means for decoding a command of the print data received by the print data receiving means and developing the command on a memory together with bitmap data. An image output system. 2. The image processing apparatus according to claim 1, wherein the host device includes a data compression unit that compresses print data including the bitmap data converted by the bitmap data conversion unit before transferring the print data to the image output device. 2. The image output system according to claim 1, further comprising a data decompressor for decompressing the print data received from the host device by the print data receiver before the data decompression by the data decompressor.