JP2001088365A - Control method of printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for controlling a printer in which lowering of speed due to compression of bit map data can be limited. SOLUTION: In the method for controlling a printer which prints print image data from a host unit while compressing, a page of print image data is divided into a plurality of bands and each band data is stored in a real frame memory. When each band data is printed while being compressed, a part of band data held in the real frame memory is printed without being compressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a printer control method, and more particularly, to a printer controller of a printer device for performing printing while compressing and holding print image data.

[0002]

2. Description of the Related Art FIG. 9 is a block diagram showing the configuration of a conventional printer having a full bitmap type print controller. Referring to FIG.
When the print image data 00 is received from the host device 100 by the receiving unit 21, the command analysis unit 22 analyzes the instruction content of the host device 100. The drawing processing unit 23 creates a drawing command corresponding to one page by referring to a drawing list stored in advance according to the instruction. The bitmap developing unit 24 develops the data into a bitmap based on the drawing command, and stores the bitmap data in the bitmap memory 25. Then, the print processing unit 26 transfers the print data to the printer engine 300 for printing.

[0003] Recently, high resolution and colorization have led to 1
More and more printer controllers that compress and hold bitmap data without mounting a memory enough to hold bitmap data for a page in the printer controller. Hereinafter, the compressed bitmap type print controller will be described. Here, one unit for performing drawing is called a band, and the unit of the band is obtained by dividing data to be printed normally in the main scanning direction.

FIG. 10 is a block diagram showing the configuration of a conventional printer having a compressed bitmap type print controller. FIG. 11 is a flowchart showing the operation of a conventional compressed bitmap type print controller. The operation of the compressed bitmap type print controller will be described with reference to both figures. Printer controller 200
Receives print image data from the host device 100 by the receiving unit 21 (step S501).
The instruction content of 0 is analyzed by the command analysis unit 22. In accordance with the contents of the instruction, the drawing processing unit 23 creates drawing commands corresponding to each of a plurality of divided bands for one page with reference to a drawing list stored in advance. The bitmap developing unit 24 develops a bitmap based on each drawing command. The band data is held in the virtual frame memory 27. Then, band data is created by allocating some bands (steps S502 and S503). The created band data is held in the real frame memory 28 (steps S504 and S505), and furthermore, the compression processing unit 29
All the band data compressed by the above is held as compressed bitmap data in the band pool memory 30 (steps S506 to S509). Thereafter, the print processing unit 26 transfers the print data to the printer engine 300 and performs printing (step S510). FIG. 12 shows the contents of each memory. In this way, only a part of the band of the bitmap data (in the virtual frame memory 27) actually required for printing is placed on the real frame memory 28, and the On the other hand, by performing compression, one page of compressed bitmap data is held in the band pool memory 30 and printing is performed.

[0005]

However, in the case of the above-mentioned conventional compressed bitmap type printer controller,
Although the memory usage is reduced, the printing speed becomes slower than when no compression is performed due to processing accompanying the compression operation.

An object of the present invention is to solve this problem, and an object of the present invention is to provide a printer control method capable of reducing a reduction in speed caused by compressing bitmap data.

[0007]

According to the printer control method of the present invention in a printer device for printing by compressing print image data from a higher-level device, the present invention solves the above-mentioned problems. Each band data obtained by dividing the print image data into a plurality of bands is held in a real frame memory. Then, when compressing and printing each band data, a printing process is performed without compressing a part of the band data held in the real frame memory before the compression, and a band other than the part of the band data is performed. The data is compressed and subjected to print processing. Therefore, by not performing compression processing on only some of the band data, the printing speed can be increased by the time during which the compression is not performed.

Further, the free memory amount of the real frame memory is compared with the band size, and when the free memory amount of the real frame memory is larger than the band size, printing processing is performed without compressing some band data. Therefore, the printing speed can be increased even for a print job of a plurality of pages.

Further, it is determined whether or not the printing mode is double-sided printing or multiple-copy printing, and when not in double-sided printing or multiple-copy printing, a printing process is performed without compressing a part of the band data to perform printing. A decrease in speed can be prevented.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Each band data obtained by dividing one page of print image data into a plurality of bands is stored in a real frame memory. Then, when compressing and printing each band data, a printing process is performed without compressing a part of the band data held in the real frame memory before compression.

[0011]

FIG. 1 is a flowchart showing the operation of a printer controller according to one embodiment of the present invention. FIG. 2 is a diagram schematically showing the operation of the present embodiment, and FIG. 3 is a diagram schematically showing the operation of a conventional print controller. 2 and 3, the same reference numerals as those in FIG. 10 indicate the same components. First, in the conventional printer controller shown in FIG.
A part of the bit map for one page is allocated to the real frame memory, the drawing data is written into the memory, and the compressed data is stored in the band pool memory. Then, band drawing for one page was performed, and when the compression and storage were completed, the compressed data was printed. On the other hand, in the present embodiment, as can be seen from FIG. 1 showing a flowchart showing the operation of the present embodiment, it is noted that the compressed data divided into bands becomes unnecessary when printing is completed and is released immediately. No compression processing is performed on some of the bands held in the real frame memory. More specifically, when the printer controller receives the print image data from the higher-level device by the receiving unit (step S101), the command analysis unit analyzes the instruction content of the higher-level device. In accordance with the content of the instruction, the drawing processing unit refers to a drawing list stored in advance and creates each drawing command corresponding to each of a plurality of bands divided for one page. The bitmap development unit develops a bitmap based on each drawing command. The band data is held in the virtual frame memory. And
Band data is created by allocating some bands (steps S102 and S103). The created band data is held in the real frame memory (step S10).
4, S105). Then, band data other than some of the band data held in the real frame memory is compressed by the compression processing unit and held as compressed bitmap data in the band pool memory (step S1).
06-S109). After that, the print processing unit transfers the print data to the printer engine and performs printing (step S110). Thus, as shown in FIG. 2, band 3 is a band on which no compression processing is performed. As a result, the processing time of the compression processing for the band on the real frame memory is not required, and the speed is expected to be improved.

Here, for example, if one band is divided by 512 lines, A4 long edged 600d
Pi splits into 19 bands. In other words, the bands remaining on the real frame memory can be at least the bands for which band drawing was performed immediately before printing and the bands several bands before the band if the size of the real frame memory is sufficiently large. For example, if the band size is 1MB
Assuming that the size of the real frame memory is 5 MB, five bands can be left in the real frame memory from the band in which the drawing was last performed. However, when printing, these bands are used for video transfer and cannot be deleted or moved, so if the entire real frame memory is used up, the band for drawing the next page will be on the real frame memory. I can't take it
Since continuous printing is not possible, conventional printer
As shown in the above, the band data had to be compressed and stored in the band pool. Thus, in the present embodiment, FIG.
As described above, compression is performed by opening a real frame memory so that drawing for the next page can be performed. At this time, the amount of memory to be freed differs depending on the paper size and is difficult to obtain. However, in this embodiment, it is noted that most of the normal print jobs are performed with the same paper size, and the band size to be printed at present is determined. By using this, the amount of memory to be freed is obtained. That is, as in steps S209 and S210 in the operation flow shown in FIG. 5, whether or not the drawing memory before compression is compressed at the time of printing for each page is determined by comparing the free memory amount X of the real frame memory with the band size. . When the available memory amount X is smaller than the band size of at least one band data, 1
The band data is compressed to the band pool memory and repeated until the free memory amount X becomes larger than the band size, and at least the free memory amount X for at least one band size is secured, and then the part held in the real frame memory The band data other than the band data is compressed by the compression processing unit and stored in the band pool memory as compressed bitmap data (step S211). afterwards,
The print processing unit transfers the data to the printer engine and performs printing (step S212).

On the other hand, when the printing mode is double-sided printing, as shown in FIG. 4B, since the printing operation is not started until the drawing of the next page is completed, the band data is left in the real frame memory. It is more advantageous not to put the real frame memory on the next page because the real frame memory can be left for drawing the next page. For this reason, in the case of the front side of double-sided printing, steps S309, S310, and S310 in the operation flow shown in FIG.
It is determined whether or not the print mode is double-sided printing as in step S311. If the printing mode is not double-sided printing, whether or not to compress the drawing memory before compression when printing each page is determined by the free space X of the real frame memory and the band. Compare the size and free memory X
Only when is smaller, one band data in the real frame memory is compressed into the band pool memory and repeated until the free memory amount X becomes larger than the band size, and at least the free memory amount X for one band size is secured. Band data other than some of the band data held in the frame memory is compressed by the compression processing unit and held as compressed bitmap data in the band pool memory (step S312). Step S309,
When double-sided printing is performed as in S313, the processing of the present embodiment as described above is not performed. Thereafter, the print processing unit transfers the print data to the printer engine and performs printing (step S31).
4). FIG. 7 shows an example of the contents held in the real frame memory and the band pool memory at the time of double-sided printing.

Further, when the print mode is a multi-copy print mode, it takes a long time to print one page, so that the time until the band is released becomes long. Also in this case, it is determined whether or not the print mode is the multiple copy printing as in S409, S410, and S411 in the operation flow shown in FIG. It is determined whether the memory is compressed or not by comparing the free space X of the real frame memory with the band size, and only when the free space X is small, compressing one band data on the real frame memory to the band pool memory to reduce the free memory X. The band processing is repeated until the band size becomes larger than the band size, and the band data other than a part of the band data held in the real frame memory is compressed by the compression processing unit after securing the free memory amount X for at least one band size. The compressed bitmap data is stored in the pool memory (step S412). When double-sided printing is performed as in steps S409 and S413, the processing of the present embodiment as described above is not performed to leave the real frame memory on the next page.
After that, the print processing unit transfers the print data to the printer engine and performs printing (step S414).

The present invention is not limited to the above embodiment, and needless to say, various modifications and substitutions can be made within the scope of the claims.

[0016]

As described above, according to the present invention,
According to the printer control method of the present invention in a printer device that performs printing by compressing print image data from a higher-level device, realizing each band data obtained by dividing print image data for one page into a plurality of bands. Store in frame memory. Then, when compressing and printing each band data, a printing process is performed without compressing some of the band data held in the real frame memory before compression, and band data other than the predetermined band data is processed. Is subjected to a printing process. Therefore, by not performing compression processing on only some of the band data, the printing speed can be increased by the time during which the compression is not performed.

Further, the free memory amount of the real frame memory is compared with the band size, and when the free memory amount of the real frame memory is larger than the band size, printing processing is performed without compressing some band data. Therefore, the printing speed can be increased even for a print job of a plurality of pages.

Further, it is determined whether or not the printing mode is double-sided printing or multiple-copy printing, and when not in double-sided printing or multiple-copy printing, a printing process is performed without compressing a part of the band data to thereby perform printing. A decrease in speed can be prevented.

[Brief description of the drawings]

FIG. 1 is a flowchart illustrating an operation of a printer controller according to an embodiment of the present invention.

FIG. 2 is a diagram showing the contents of each memory in the present embodiment.

FIG. 3 is a diagram showing the contents of each memory in a conventional example.

FIG. 4 is a diagram illustrating the contents of a real frame memory during continuous printing according to the present embodiment.

FIG. 5 is a flowchart illustrating an operation of a printer controller according to another embodiment of the present invention.

FIG. 6 is a flowchart illustrating the operation of the printer controller during duplex printing.

FIG. 7 is a diagram showing the contents of a real frame memory and a band pool memory when printing a plurality of copies.

FIG. 8 is a flowchart illustrating an operation of the printer controller when printing a plurality of copies.

FIG. 9 is a block diagram showing a configuration of a conventional printer device having a full bitmap type printer controller.

FIG. 10 is a block diagram showing a configuration of a conventional printer device having a compressed bitmap type printer controller.

FIG. 11 is a flowchart showing the operation of a conventional compressed bitmap printer controller.

FIG. 12 is a diagram showing the contents of each memory by a conventional compressed bitmap printer controller.

[Explanation of symbols]

21: receiving unit, 22: command analyzing unit, 23: drawing processing unit, 24: bitmap developing unit, 25: bitmap memory, 26: print processing unit, 27: virtual frame memory,
28: Real frame memory, 29: Compression processing unit, 3
0: Band pool memory, 100: Host device, 200:
Printer controller, 300: printer engine.

Claims (3)

[Claims] 1. A printer device for compressing and printing print image data from a higher-level device, wherein each band data obtained by dividing print image data for one page into a plurality of bands is stored in a real frame memory. A printer control method for performing printing processing without compressing a part of band data held in a real frame memory before compression when compressing and printing each band data. 2. The printing apparatus according to claim 1, wherein a free memory amount of the real frame memory is compared with a band size, and when the free memory amount of the real frame memory is larger than the band size, a printing process is performed without compressing a part of band data. The printer control method described above. 3. The method according to claim 1, wherein the control unit determines whether the print mode is duplex printing or multi-copy printing, and performs the printing process without compressing some band data when the printing mode is not duplex printing or multi-copy printing. 3. The printer control method according to item 2.