JP2814970B2 - Printer system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer system, and more particularly, to print data (image) compressed by a host device.
The printer system transfers the print data to a printer device.

[0002]

2. Description of the Related Art In a conventional printer system for transmitting compressed data from a host computer to a printer, when transmitting image data from the host computer to the printer, the amount of data to be transferred is reduced and the transfer time is reduced. Then, the data is transferred after being compressed by a certain compression method.

[0003] Japanese Patent Application Laid-Open No. 4-10068 discloses a technique in which a binary image and a multi-valued image are compressed and transmitted by different compression methods, and characters are transmitted by code, and are combined with the two images on the receiving side and printed. Have been described. In this method, compression is performed using one compression unit when attention is paid to binary data.

As shown in FIG. 4, the conventional printer system is provided with one compression means 24 in the host computer 20, while the printer device 30 is provided with one decompression means 34 corresponding to the compression means 24. I have.

[0005]

However, high compression ratios can be obtained for certain image data by the compression method possessed by the printer system, but only low compression ratios can be obtained for other image data. There is a problem that the data amount cannot always be stably and efficiently reduced by only one compression method.

[0006]

An object of the present invention is to solve the disadvantages of the conventional example, and particularly to a case where various types of image data are printed.
It is therefore an object of the present invention to provide a print system capable of printing in a short time .

[0007]

Therefore, in the present invention, as a first means, data such as characters or figures are converted to image data.
And includes a host device having a printer driver for converting the print data which is over data, and a printer device having a print unit that prints the print data transmitted from the host device. Moreover, the printer driver, a plurality of compression means for compressing the image data <br/> by different compression methods, Image
And compression means selecting unit for selecting the compressing means in accordance with the Jideta, compressing means and a data transmission unit for transmitting the image data compressed to the printer selected by the compressing unit selection unit. Also, if the compression means
Compress a part of the data and calculate the data amount information after the compression
A data amount information calculation function to be output, and a compression means selection unit.
Is the same image data calculated by each compression means.
Based on the amount of data for a portion of the data
It has a data amount selection function to select. Then, the printer device performs image processing according to the compression method of the plurality of compression units.
A plurality of expansion means for expanding Jideta, the expansion means as well as selecting a compression method identification unit determines a compression method of image data transmitted from the host device, the expansion means on the basis of the compression method identification unit of the judgment result Output from
And a developing unit for developing the image data and outputting the developed image data to the printing unit.

[0008] In the first means, the compression means selecting unit includes:
The compression means is selected in accordance with the type of image data, and in the printer device, the compression means determination unit determines whether the received image data has been compressed by which compression means. In the data transfer, print data compressed by a desirable compression unit according to the type of print is transferred. Therefore, the host device
Image data transfer time from the printer to the printer
Be shortened. And using a part of the image data
In order to select the compression method, use the compression method
Time is not long. This allows the entire printing time
The body is shortened.

In the second means, in addition to the matter specifying the first means, a data amount information calculating function is provided for calculating the image data.
Of which the first few lines are part of the image data
It adopts the configuration described above.

[0010] In the third means, one of the compression means of the multiple compression means compresses a portion of print data with a compression ratio calculating function for calculating the compression ratio of the compression, the compression means selected A first compression ratio selection function for selecting a compression unit for which the compression ratio has been calculated when the compression ratio calculated by the compression unit exceeds a predetermined threshold value; If the threshold value is not exceeded, a second compression ratio selection function for selecting a compression unit other than the compression unit that has calculated the compression ratio is provided.

The present invention aims to achieve the above-mentioned object by each of these means.

[0012]

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

FIG. 1 is a block diagram showing the configuration of a printer system according to the present invention. The printer system converts character or graphic data into image data (print data).
Device (host computer) 20 having a printer driver 21 for converting the print data into a print data, and a printing unit 36 for printing the print data transmitted from the host computer 20.
And a printer device 30 having the same.

Further, the printer driver 21 includes a plurality of compression means 24 for compressing print data by different compression methods.
And compression means 24, 25 according to the type of print data.
And a data transmission unit 23 for transmitting the print data compressed by the compression unit 24 selected by the compression unit selection unit 22 to the printer device 30.

Further, the printer device 30 includes a plurality of decompression means 34 and 35 for decompressing print data according to the compression method of the plurality of compression means 24 and 25,
0, a compressing means determining unit 32 for determining a compressing method of the print data transmitted from 0, and selecting the decompressing means 34 and 35 based on the result of the determination by the compressing means determining unit 32, and the printing output from the decompressing means 34. A developing unit 35 for developing data and outputting the developed data to the printing unit 36.

This will be described in detail.

Each of the compression means 24 and 25 records the compression method as a code at the beginning of the data at the time of compression, and the compression means determination section 32 determines the compression means based on the code indicating the compression method.

The compression means 24 and 25 efficiently compress especially image data among print data. In the example shown in FIG. 1, the compression means is described as two types. Hereinafter, the compression means 24 and 25 are referred to as compression means A (first compression means 2).
4), referred to as compression means B (second compression means 25).

The compression means A and B are provided with buffers A and B for temporarily storing compressed data (reference numerals 28 and 29). The compression means A and B store the data in the buffers A and B while compressing the print data.
Is transmitted to the printer device 30.

The compression means is provided with a compression information storage section A and a compression information storage section B for storing the data amount of the data compressed by the compression means A and the compression means B (reference numerals 26 and 26). 27).

The compression means selection section 22 selects a compression means based on the data amount information stored in the compression information storage section A and the compression information storage section B. For this reason, the host computer 20 compresses the same print data using the compression unit that can reduce the data amount among the two compression units. Further, the compression unit selection unit 22 notifies the data transmission unit which compression unit is the selected compression unit.

The printer 30 includes a data receiving unit 31 for receiving print data transmitted from the host computer 20, a compression unit determining unit 32 for determining a data compressing unit, and a decompressing unit for decompressing the compressed data. A (reference numeral 34) and expansion means B (reference numeral 35).

Next, the operation of the printer system will be described. FIG. 2 is a flowchart showing the selection processing of the compression means.

In the embodiment shown in FIG. 2, there is a case where the memory for one page cannot be secured by the host computer in many cases. Therefore, in this embodiment, the processing is performed for each band. The band width and the number of bands are determined by the amount of memory that can be secured by the host computer, the size of the print image, and the resolution.

For example, when the size of the print image is A4 and the resolution is 600 dpi, 4 megabytes of memory is required. The divided size is obtained, and the number of bands is eight.

When the amount of memory that can be secured by the host computer 20 is 4 megabytes or more, band processing may not be necessary.

The compression means A performs one-dimensional compression which supports only horizontal compression of image data, and the compression means B performs two-dimensional compression which supports vertical compression in addition to horizontal compression of image data. I do.

First, in step S11 of FIG. 2, the first few lines of the band are compressed by the compression means A, the data amount is stored in the compression information storage unit A, and the compressed data is stored in the buffer A.

Next, in step S12, the first few lines of the band are compressed by the compression means B, the data amount is stored in the compression information storage section B, and the compressed data is stored in the buffer B.

In step S13, the compressed data amount (Data A) of the compression means A and the compressed data amount (Data A) of the compression means B
If the value of Data A is greater than or equal to the value of Data B (step S14), the compression means A is selected and the compression is continued after the buffer A.

When the value of Data B is larger than the value of Data B (step S15), the compression means B is selected, and the compression means B continues the compression after the buffer B. The data amount selection function is realized by steps S13 to S15.

In step S16, it is determined whether or not the current band is the last band.
The processing of the next band is performed in the same manner from step 1.

In this manner, the data compression ratio can be increased and the amount of data transmitted from the host computer to the printer can be reduced.

Next, another embodiment will be described.

In this embodiment, a plurality of compression means 24, 2
5, one of the compression means 24 has a compression ratio calculation function of compressing a part of the print data to calculate the compression ratio of the compression. A first compression ratio selection function for selecting the compression means 24 which has calculated the compression ratio when the compression ratio exceeds a predetermined threshold value; Has a second compression ratio selection function of selecting a compression unit 25 other than the compression unit that has calculated the compression ratio.

FIG. 3 is a flowchart showing a process of selecting a compression means according to this embodiment. Under the same conditions as in the above-described embodiment, the compression means 24 and 25 are
It will be described as.

First, in step S41, the compression ratio (RATIO B) of the compression means B is stored in the compression information storage section B, and the compressed data of the compression means B is stored in the buffer B.

In step S42, the compression ratio RATIO B by the compression means B is compared with a predetermined threshold value, and R
If ATIO B is greater than or equal to the threshold value (step S43), compression is continued by the compression means B after the buffer B.

Conversely, when the threshold value is larger than RATIO B (step S44), compression is performed by the compression means A.

In step S45, it is determined whether or not the current band is the last band.
The processing of the next band is performed in the same manner from step 1.

In this way, it is possible to increase the data compression ratio and reduce the data transmitted from the host computer to the printer.

This embodiment is very effective when the compression means B has a very high compression ratio with respect to certain data than the compression means A.

In this embodiment, when the compression by the compression means B is selected, the compression by the compression means A is not performed at all, so that the time for selecting the compression means is reduced.

In this embodiment, the compression means and the expansion means 2
There is only one way, but there may be more.

In this embodiment, one-dimensional compression that supports only horizontal compression of image data and two-dimensional compression that supports vertical compression in addition to horizontal compression of image data are used as compression means. It is not limited.

As described above, according to the present embodiment, efficient compression of image data for each band can be performed by a host computer having a plurality of data compression means, so that the image data can be transferred to a printer having data expansion means. This has the effect of reducing the data amount and the transfer time.

[0047]

According to the present invention, the compression means selecting section selects the compression means according to the type of the image data, and the compression means determining section determines whether the received print data has been received. In order to determine which compression unit has been used to compress the data, the data transfer between the host device and the printer device involves transferring the print data compressed by the desired compression unit according to the type of image data. Because of this, printing time can be reduced
Yes, and by compressing part of the image data
Quickly select compression means to select compression means
With these, a wide variety of image data
It is possible to provide an unprecedented excellent printing system in which the printing time can be reduced even when printing is performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a flowchart showing a method of selecting a compression unit according to the embodiment having the configuration shown in FIG. 1;

FIG. 3 is a flowchart showing another method of selecting a compression unit according to another embodiment having the configuration shown in FIG. 1;

FIG. 4 is a block diagram illustrating a configuration example of a conventional printer system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 20 host device (host computer) 21 printer driver 22 compression means selection unit 23 data transmission unit 24 compression means (compression means A) 25 compression means (compression means B) 26, 27 compression information storage units A, B 28, 29 buffer A , B 30 printer device 31 data receiving unit 32 compression means determination unit 33 decompression unit 34 decompression means (decompression means A) 35 decompression means (decompression means B) 36 printing unit

Claims (3)

(57) [Claims] 1. Data such as characters or figures are converted into image data.
A host device having a printer driver for converting the print data is data, in the printer system including a printer having a printing unit for printing the print data sent from the host device, the printer driver, the image data A plurality of compression means for compressing the image data by different compression methods;
Comprising a compression means selecting unit for selecting the compressing means in accordance with the chromatography data, and a data transmitter for transmitting image data compression means has compressed selected by the compression means selecting unit to the printer device, the compression means However, by compressing a part of the image data
Data amount information calculation for calculating the data amount information after compression
The compression means selection unit has a function.
Data volume of a part of the same image data
A data amount selection function for selecting the compression means based on the
For example, the printer apparatus, a plurality of expansion means for expanding the image data in accordance with the method of compressing the plurality of compression means, and compressing means determining unit determines how the compressed image data sent from said host device A decompressing unit that selects the decompressing unit based on the result of the judgment by the compression unit judging unit and decompresses the image data output from the decompressing unit and outputs the image data to the printing unit. system. 2. The data amount information calculating function according to claim 1 , wherein
The first few lines of the image data
The printer system of claim 1 wherein feature to be part of. (3)Image data such as characters or figures
A printer driver that converts the data to print data
Host device and the print data transmitted from this host device.
Printer device having a printing unit for printing data.
In the printer system, The printer driver differs in the image data
A plurality of compression means for performing compression by a compression method;
Compression means selection unit for selecting the compression means according to data
And the compression means selected by the compression means selection unit
Sending the compressed image data to the printer device
A data transmission unit, One of the plurality of compression means is the compression means.
Compress a part of image data and calculate the compression ratio of the compression
With a compression ratio calculation function The compression means selection section is calculated by the compression means.
If the compression ratio exceeds the specified threshold,
A first compression ratio selector for selecting a compression means for which a compression ratio has been calculated
Function and the compression rate does not exceed the specified threshold
Select a compression means other than the compression means that calculated the compression ratio.
And a second compression ratio selection function for selecting The printer device may be adapted to the compression method of
A plurality of decompression means for decompressing the image data accordingly
And the pressure of the image data transmitted from the host device.
Compression means determining section for determining a compression method, and compression means determination
Selecting the decompression means based on the determination result of the section
Expand the image data output from the decompression means
A developing unit for outputting to the printing unit.
Printer system.