JP3211711B2 - Drawing device, drawing method, printer and image display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drawing device, a drawing method, a printer, and an image display device for performing a drawing process by a so-called banding method.

[0002]

2. Description of the Related Art Conventionally, in the field of page printers and the like, one page is divided into a plurality of bands when print data composed of code data is expanded into bitmap data in order to save memory. Do the deployment,
A drawing apparatus having a so-called banding function is known. When one page is divided into a plurality of bands and developed in a drawing memory (band buffer), an intermediate code to which management information for distributing print data for each band is added, and an intermediate buffer for storing this is stored. Must be provided.

[0003] The data amount of the intermediate code stored in the intermediate buffer largely depends on at what level from the so-called code data to the bitmap data the intermediate code is generated. Generally, in a drawing apparatus that stores drawing information instructing drawing and attribute information attached to the drawing information in an intermediate buffer as an intermediate code, the code amount becomes smaller as the level is closer to the print data (code data such as PDL). Then, as the level closer to the bitmap data that has been further developed is adopted, the code amount increases. Here, the drawing information and the attribute information may have various formats depending on the level of the intermediate code and the like.
For example, the drawing information includes designation of drawing of a point, a line, and a rectangular area, and the attribute information includes information on a fill pattern (information on the presence / absence of a pattern and a type of pattern) and a logical operation between a source and a destination memory. , Clip area designation, and the like.

Therefore, in order to reduce the code amount of the intermediate code and reduce the capacity of the intermediate buffer, it is desirable to employ an intermediate code at a level closer to the print data. However, even when an intermediate code at a level close to the print data is employed, so-called overflow, which exceeds the capacity of the intermediate buffer, may occur in the case of complex code data due to an increase in attribute information and the like. is there. Conventionally, as a countermeasure against such an overflow, as a countermeasure, a part of the intermediate code stored in the intermediate buffer is first expanded into a band buffer and compressed and stored in another storage area. There is a method of storing the intermediate code in the intermediate buffer, and then combining the compressed data with the decompressed data when expanding the intermediate code into the band buffer. As another countermeasure, there is a method of reducing the code amount by recreating the intermediate code at a low resolution.

[0005]

By the way, when a high level such as drawing information and attribute information is adopted as the intermediate code, the ratio of the attribute information to the whole becomes large. As a countermeasure for further reducing the above, a method of storing the attribute information in the intermediate buffer only when the value of the attribute information has changed can be considered. However, in this method, there is a problem that image quality is deteriorated due to inconsistency of attribute information when the intermediate code is developed for each band. Specifically, when sequentially outputting from the intermediate buffer from the entry of the first band (drawing information belonging to the band) to the entry of the last band, at the start of the output of the entry of each band, the initial setting of the attribute information to be originally set is performed. There is a problem that the value is not set, attribute information corresponding to the last entry of the previous band is set, and drawing is performed based on incorrect attribute information.

The present invention has been made under such a background. When one page is divided into bands and developed as bitmap data in a drawing memory, there is no inconsistency in attribute information. It is an object of the present invention to provide a drawing device, a drawing method, a printer, and an image display device that can reduce the amount of intermediate codes by thinning out the attribute information.

[0007]

In order to solve the above-mentioned problems, the present invention provides at least drawing information for instructing drawing and attribute information for designating the changed attribute only when the attribute of the drawing information changes. This is a drawing device that converts code data of a page image into bitmap data and develops the drawing data in a drawing memory, and inserts management information for dividing the page image into band units and developing the input code data. Intermediate code generation means for generating an intermediate code;
A randomly accessible intermediate buffer for storing an intermediate code generated by the intermediate code generation means, a storage means for storing an initial value of attribute information designated at the beginning of a page in the code data, and the intermediate buffer Developing means for reading out an intermediate code for each band from the first and second bands and sequentially developing partial images from a first band to an n-th band (n is an integer of 2 or more) in a drawing memory based on the drawing information and the attribute information; When the developing means starts developing from the beginning of each band, the information processing apparatus further comprises attribute information specifying means for specifying the initial value of the attribute information stored in the storage means to the developing means.

Preferably, when the code amount of the intermediate code exceeds the capacity of the intermediate buffer, the present invention expands the data of the portion written in the intermediate buffer to the drawing memory by the expansion unit. Control means for writing the remaining overflow data to the intermediate buffer after the preceding execution, developing the data into the drawing memory by the developing means, and combining the data with the previously developed part; and When overflow occurs, the second storage means for storing attribute information specified immediately before the overflow occurs, and when the expansion means starts expansion from the head of overflow data written in the intermediate buffer,
A second attribute information designating means for designating the attribute information stored in the second storage means to the developing means.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. A: First Embodiment (1) Configuration FIG. 1 is a functional block diagram showing a configuration of a first embodiment of the present invention. The embodiment shown in this figure is, for example, a printer that draws and outputs an image corresponding to supplied print data in page units.
rocessing Unit), ROM (Read Only Memory), RAM
(Random Access Memory) and the like to control the following functions.

In FIG. 1, print data 100 is
Code data input via a network interface, serial interface, parallel interface, or the like. This code data is composed of a page description language and emulation data.

Based on the data amount of one page of the input print data 100, the optimum drawing method determining unit 101 determines whether to draw by a frame method of drawing in page units or to draw in band units obtained by dividing the page into several parts. It is determined whether to perform drawing by the band method to be performed.

The command analyzer 102 interprets the input print data 100. Here, the print data 10
0 is roughly composed of drawing information and attribute information. The drawing information is, for example, information for specifying a drawing such as a point, a line, and a rectangular area. On the other hand, the attribute information includes unique attribute information unique to each drawing element, such as information on a paint pattern, and common attribute information common to the entire print data, such as line thickness and font.

When the interpreted code data is the common attribute information, the common attribute information extraction unit 103 determines whether the common attribute information has changed from the previous value, and if the code data has changed, the intermediate The data is controlled to be stored in the buffer 106. For example, as shown in FIG. 2, three types of common attribute information A (i), B (i), and C (i) (where i is a sequential number, and when i is incremented, the value changes. Print data 100)
Is supplied, since the value of the common attribute information shaded in the list has not changed from the previous value, it is thinned out by the common attribute information extraction unit 103 and stored in the intermediate buffer 106 (code 100 '). Even if such thinning is performed, it can be restored by inserting the same value as the previous value (reference numeral 100 ″).

The common attribute information initial value storage unit 104 is means for storing the initial value of the common attribute information in a predetermined storage area set on a RAM (not shown). Here, the initial value of the common attribute information refers to the value of the common attribute information specified first in each page of the print data 100 input in principle. The common attribute information initial value storage unit 1
In a case where an overflow occurs in the intermediate buffer 106 described later, a value of the common attribute information written in the intermediate buffer 106 immediately before the overflow occurs is stored in addition to the initial value of the common attribute information.

The intermediate code generation unit 105 includes an instruction analysis unit 1
The mapping information indicating the band to which each piece of drawing information belongs is added to the piece of drawing information interpreted by 02, and an entry of an intermediate code is generated. The intermediate buffer 106
This is a RAM for temporarily storing the intermediate code output from the intermediate code generation unit 105.

The common attribute information initial value setting section 107 reads the common attribute information stored in the common attribute information initial value storage section 104 and sets this as the initial value of the common attribute information at the start of the development of each band. In principle, the common attribute information specified at the beginning of the page is set as an initial value. If overflow occurs in the intermediate buffer 106, the value of the common attribute information written in the intermediate buffer 106 immediately before the overflow occurs Set.

If the intermediate code read from the intermediate buffer 105 is the common attribute information, the common attribute information restoring unit 108 updates the setting of the common attribute information according to the value.

The developing section 109 interprets the intermediate code read from the intermediate buffer 105 and develops the intermediate code in the band buffer 110 as bitmap data. The band buffer 110 is a RAM that holds bitmap data expanded by the expansion unit 109 based on the intermediate code in band units.
It is. Therefore, the capacity is configured to be large enough to store one band of bitmap data. The bitmap data of each band expanded here is once compressed by a compression unit (not shown) as necessary, and temporarily saved in a memory (not shown) for storing compressed data.

Further, the image forming section 111 prints and records bitmap data sequentially output for each band from the band buffer 108 on a printing medium such as paper. Here, FIG.
Indicates the correspondence between the contents of the page image finally printed and recorded by the banding method and the contents of the base intermediate code. In this figure, the entry of the character "A" in which the character size of 8 points is specified specifies the drawing position belonging to the second band, and the entry of the character "B" in which the character size of 12 points is specified is The drawing position belonging to the first band is specified in the entry of the character "C" in which the drawing position belonging to the four bands is specified and the character size of 10 points is specified.

(2) Outline of Operation Next, an outline of the operation of the embodiment having the above configuration will be described. In the following, it is assumed that one page of print data is converted into an intermediate code, stored in the intermediate buffer 106, read out for each band, and rendered in the band buffer 110 by the developing unit 109. This operation includes an intermediate code input phase for storing all entries of a drawing page in the intermediate buffer 106, and an intermediate buffer 10
6 comprises an intermediate code output phase for outputting and drawing all the entries stored in 6. Hereinafter, each phase will be described separately.

First, in the intermediate code input phase, when the print data 1 is input, the print data 1 is analyzed by the instruction analysis unit 102, and is further converted into an intermediate code by the intermediate code generation unit 105. The data is stored in the buffer 106. That is, a graphic entry is generated from the drawing information and the unique attribute information, and the common attribute information is used as the common attribute entry. Here, all the graphic entries are stored in the intermediate buffer 106. For the common attribute entries, the common attribute information extraction unit 103 determines whether or not there is a change from the previous value. 106. In addition, in order to cope with band division, mapping information, which is management information for determining which band the entry belongs to, is added to each entry. That is, mapping information indicating the band in which the figure is drawn is added to the figure entry, and mapping information indicating that the information is related to all bands is added to the common attribute entry. On the other hand, the common attribute information initial value storage unit 104 stores the initial value of the common attribute information specified at the top of the page of the print data. As described above, after all the entries of one page are stored in the intermediate buffer 106, the process proceeds to the next intermediate code output phase.

Intermediate Code Output Phase Next, in the intermediate code output phase, first, the common attribute information initial value setting unit 107 sets the initial value of the common attribute information stored in the common attribute information initial value storage unit 104 to the first common attribute. Set as information. Then, the intermediate buffer 106
, The entries relating to the first band are sequentially read out, and are expanded in the band buffer 110 by the expansion unit 109. During this time, when a new attribute value is specified by the common attribute entry, the common attribute information restoring unit 108 updates the setting of the common attribute information with the new value.

When all the entries related to the first band are developed as bitmap data in the band buffer 110, the data is transferred to the image forming unit 111 and printed. On the other hand, the common attribute information initial value setting unit 107
Reads out the initial value of the common attribute information stored in the common attribute information initial value storage unit 104, resets it again, and starts developing the second band. The same processing is performed for the subsequent bands as described above, and the development is sequentially performed for each band. Thereby, inconsistency of the common attribute information due to banding is avoided.

The above operation is performed by
It is assumed that all entries of a page can be stored. However, if all entries of one page cannot be stored, that is, if overflow occurs in the intermediate buffer 106, the entries that can be stored in the intermediate buffer 106 are temporarily set. The stored data is stored in the band buffer 110 by the developing unit 109.
Draw each band. In this case, band buffer 1
In 10, the bitmap data of each band is compressed and saved in another compressed data storage area so that the previous band is not overwritten by drawing the next band.

When the expansion is completed for all the bands, the remaining overflowed entries are stored in the intermediate buffer 106.
, The band is expanded by the expansion unit 109 and combined with the expanded data temporarily saved earlier in the band buffer 110. That is, when decompressing the remaining data of each band, the compressed data of the corresponding band that has been saved is decompressed and decompressed again to the band buffer 110, and this is combined with the remaining decompressed data.

As described above, when an entry for one page does not fit in the intermediate buffer 106 and the overflow is developed later, the common attribute information written in the intermediate buffer 106 immediately before the overflow occurs. When the values are stored in the common attribute information initial value storage unit 104 and the entry expansion is started for each band of the overflowed data,
This value is set as the initial value of the common attribute information. Thereby, inconsistency of the common attribute information is avoided.

(3) Details of Operation Next, details of the operation of this embodiment will be described with reference to the flowcharts shown in FIGS. FIG. 4 is a flowchart showing the main routine of the control program executed by the CPU, and mainly shows the contents of the drawing processing by the banding method. In the figure, when the power is first turned on, the apparatus is initialized (S500).
Then, when print data is supplied via a predetermined input interface, it is determined based on the page size or the like whether to draw in the frame method or the banding method (S501). If it is determined that drawing can be performed by the frame method such as when the page size is small, drawing is performed by the frame method (S502). The description of the drawing by the frame method is omitted because a known drawing method is adopted. On the other hand, when it is determined that drawing is necessary in the banding method due to a large page size or the like, the following processing is executed (S503 to S51).
1).

That is, first, prior to the development of each page, information relating to storage in the intermediate buffer 106 such as the number of band divisions is initialized (S503). Note that DL in the flowchart is an abbreviation of a display list, which means the intermediate buffer 106. Then, the supplied print data is interpreted, and an entry to the intermediate buffer 106 is created (S504). Next, it is determined whether or not an overflow has occurred in the intermediate buffer 106, and if an overflow has occurred, the process proceeds to temporary development processing in the intermediate buffer 106 (S506). This temporary expansion processing will be described later. On the other hand, if no overflow occurs, the process proceeds to the following processing to store the entry (S507 to S51).
1).

First, it is determined whether or not the data is stored at the head of the intermediate buffer 106 (that is, whether or not it is the head of the page). The initial value of the common attribute information is stored (S508). Next, the entries are sequentially stored in the intermediate buffer 106 until the storage of all the entries of the page is completed (S510) (S509). Then, when the storage of all the entries of the page is completed (S510), the intermediate buffer 106 is expanded (S511).

FIG. 5 is a flow chart showing the subroutine executed in S511, and shows the contents of the processing of expanding the data in the intermediate buffer 106. In FIG. 5, when the expansion processing to the intermediate buffer 106 is started (S600), first, a loop counter is initialized to expand sequentially from the first band (S601). Then, an initial value of the common attribute information stored in the common attribute information initial value storage unit 104 is set (S602). Next, it is determined whether or not the compressed and stored data exists (S6).
03). This is based on the assumption that data overflow has already occurred. Here, if the compressed data exists, the compressed data is expanded (S6).
05), the entry of the band is expanded, and the expanded data and the expanded data are combined and transmitted to the image forming unit 111 (S606).

On the other hand, if there is no compressed and stored data, the processing of S605 and S606 is not performed, and
The entry of the band is developed and transmitted to the image forming unit 111 (S604). Thus, the loop counter is incremented from the first band to the last band (S60).
8) The above operation is repeated until the expansion processing of all bands is completed (S602 to S608), and the expansion processing of the page is ended (S609).

FIG. 6 is a flowchart showing a subroutine executed in S506 (see FIG. 4) described above, and shows the contents of the temporary expansion processing performed when the intermediate buffer 106 overflows. In FIG. 6, when the temporary development processing to the intermediate buffer 106 is started (S7)
00) First, a loop counter is initialized to perform temporary expansion sequentially from the first band (S701). Then, an initial value of the common attribute information stored in the common attribute information initial value storage unit 104 is set (S702). However, the initial value of the common attribute information here is not the common attribute information specified at the beginning of the page, but the common attribute information written in the intermediate buffer 106 immediately before the data overflow. Next, it is determined whether or not the compressed and stored data exists (S703). This also assumes that data overflow has already occurred before the data overflow. Here, if there is data that has been compressed and stored, one of the compressed data is decompressed (S70).
5) Expand the entry of the band, synthesize the expanded data and the decompressed data, and compress and save (S70)
6). Here, the reason why the data is not sent to the image forming unit 111 is to wait until the remaining data that has overflowed the data this time is expanded.

On the other hand, if there is no compressed and stored data, the processing of S705 and S706 is not performed, and
The entry of the band is expanded and compressed and stored (S70).
4). This is also not sent to the image forming unit 111 because it waits for the remaining data that has overflowed this time to be developed. In this way, while the loop counter is incremented from the first band to the last band (S708), the above operation is repeated until the temporary expansion processing of all the bands is completed (S702 to S708), and the temporary expansion processing when data overflow occurs is terminated (S702). S709).

(4) Effect As described above, according to the present embodiment, the value of the common attribute information is changed in order to reduce the code amount of the intermediate code in the development to the bitmap data by the banding method. Even when the data is stored in the intermediate buffer 106 only in such a case, the problem of inconsistency that the common attribute information differs from the value of the main body at the start of the development of each band does not occur. The intermediate code for one page is stored in the intermediate buffer 1.
Since the overflow did not take place in 06, the problem of inconsistency does not occur even when the expansion processing is performed a plurality of times.

B: Second Embodiment Next, a second embodiment will be described. This embodiment is different from the first embodiment in that the initial value of the common attribute information is stored in a fixed area starting from the top of the intermediate buffer 106 without particularly providing the common attribute information initial value storage unit 104. It is in the place. For other points,
This is the same as the embodiment.

Then, in the intermediate code input phase, when storing the entry generated by the intermediate code generation unit 105 from the head of the intermediate buffer 106, first store the initial value of the common attribute information at the head of the intermediate buffer 106, Following this, the entries are sequentially stored. That is,
The initial value of the common attribute information is always stored in the head area of the intermediate buffer 106.

On the other hand, in the intermediate code output phase, the expansion unit 109 can inevitably read the initial value of the common attribute information only by accessing from the beginning of the intermediate buffer 106, and as in the first embodiment, It is not necessary to perform a special memory access for setting an initial value of information.

In the case where overflow occurs in the intermediate buffer 106 and one page entry is divided and stored a plurality of times, the common attribute information entered immediately before the overflow occurs is added to the top of the intermediate buffer 106. By storing, no special memory access for setting the initial value of the common attribute information is required as in the case described above.

As described above, the initial value of the common attribute information is stored at the head of the intermediate buffer 3 irrespective of the presence or absence of overflow, so that the developing unit 109 starts the access from the head of the intermediate buffer 106. This includes a process of setting an initial value of the common attribute information before drawing each band, thereby simplifying the process.

C: Modifications The present invention is not limited to the above-described embodiment, and various modifications as described below are possible. (1) For example, in the embodiment, the case where the print data attached to each piece of drawing information is supplied regardless of whether or not the common attribute information has changed is described, but the present invention is applicable to such a form. The present invention is not limited to this, and can be applied to a case where print data is supplied in a form in which common attribute information that has not changed from the previous value is removed (so-called thinned-out form). In this case, the common attribute information extraction unit 1 of the embodiment
03 can be omitted.

(2) If the capacity of the intermediate buffer 106 is sufficient and there is no possibility of overflow,
The process for avoiding inconsistency of the common attribute information is to store the common attribute information specified first at the top of the page as the initial value, and only to set this at the time of development, when overflow occurs. No countermeasures are required.

(3) In the embodiment, the case where the present invention is applied to a printer has been described as an example. However, the present invention is not limited to this, and may be applied to other image output devices such as an image display device such as a display device. It is possible.

(4) Although the present invention is embodied in the embodiment as a drawing device incorporated in a printer, it can be understood as a drawing method for operating the printer as in the embodiment. In addition, the processing procedure of the embodiment can be configured as a program for causing a microcomputer that controls a printer to execute the processing procedure. The program can be recorded on a recording medium such as a floppy disk and ported to another device.

[0044]

As described above, according to the present invention, when one page is divided into bands by a so-called banding method and is developed as bitmap data in a drawing memory, inconsistency of attribute information is involved. In addition, it is possible to reduce the code amount of the intermediate code by thinning out the attribute information.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a schematic diagram for explaining thinning of an intermediate code and its restoration in the embodiment.

FIG. 3 is a schematic diagram showing a correspondence between an output image and an intermediate code according to the banding method in the embodiment.

FIG. 4 is a flowchart showing a main routine of a control program executed by a CPU in the embodiment.

FIG. 5 is a flowchart showing a subroutine for expanding a control program executed by a CPU in the embodiment.

FIG. 6 is a flowchart showing a subroutine for temporarily expanding a control program executed by a CPU in the embodiment.

[Explanation of symbols]

101: optimal drawing method determination unit (switching unit), 102: instruction analysis unit, 103, common attribute information extraction unit, 104: common attribute information initial value storage unit (storage unit), 105: intermediate code generation unit (intermediate code generation) Means: 106 intermediate buffer; 107: common attribute information initial value setting unit (attribute information designating unit); 108: common attribute information restoring unit; 109: developing unit (developing unit); 110: band buffer (drawing memory); 111: Image forming unit.

Claims (10)

(57) [Claims] 1. A page image code data comprising at least drawing information for instructing drawing and attribute information for specifying the changed attribute only when the attribute of the drawing information changes, is converted to bitmap data for drawing. A rendering device for developing in a memory, wherein intermediate code generating means for generating intermediate code by inserting management information for dividing a page image into band units and developing the code image into input code data; A random accessible intermediate buffer for storing the intermediate code generated by the above, storage means for storing an initial value of attribute information designated at the beginning of the page in the code data, and banding the intermediate code from the intermediate buffer Each time, and reads from the first band to the n-th band (n is an integer of 2 or more) based on the drawing information and the attribute information. Developing means for sequentially developing the divided images in the drawing memory; and, when the developing means starts developing from the beginning of each band, attribute information designation for designating the initial value of the attribute information stored in the storage means to the developing means. And a drawing device. 2. When the code amount of the intermediate code exceeds the capacity of the intermediate buffer, after the data of the portion written in the intermediate buffer is first developed into the drawing memory by the developing means, Control means for writing the remaining overflow data to the intermediate buffer, developing the same in the drawing memory by the developing means, and combining it with the previously developed part; and when the intermediate buffer overflows, A second storage unit for storing the attribute information specified immediately before the overflow occurs; and a second storage unit, when the expansion unit starts expansion from the head of the overflow data written in the intermediate buffer. 2. The drawing apparatus according to claim 1, further comprising second attribute information designating means for designating the stored attribute information to the developing means. 3. A code data including attribute information for each drawing information regardless of a change in attribute is input, the presence / absence of an attribute change is detected from the code data, and an attribute unchanged from a previous attribute is designated. 2. The method according to claim 1, further comprising removing means for removing attribute information from the code data.
The drawing apparatus described in the above. 4. The drawing apparatus according to claim 1, wherein a storage area of said storage means is set to a first area where access of said intermediate buffer is started. 5. The drawing apparatus according to claim 2, wherein the storage areas of the storage unit and the second storage unit are set to a head area where access to the intermediate buffer is started. 6. A first method of drawing a frame for each page.
And a second operation mode in which one page is divided for each band and drawing is performed in a banding method, and switching is performed to switch in which of the first and second operation modes the drawing is performed. 2. The drawing apparatus according to claim 1, further comprising means. 7. A page image code data comprising at least drawing information for instructing drawing and attribute information for specifying the changed attribute only when the attribute of the drawing information changes, is converted to bitmap data for drawing. A drawing method for developing in a memory, comprising the steps of: inserting management information for dividing a page image into band units and developing the page image into input code data to generate an intermediate code; and Storing an initial value of the attribute information specified first in a predetermined storage unit; storing the intermediate code generated by the intermediate code generation unit in a randomly accessible intermediate buffer; The code is read for each band, and the partial images from the first band to the n-th band are drawn based on the drawing information and the attribute information. And sequentially specifying the initial value of the attribute information stored in the storage means to the development means when the development means starts the development from the beginning of each band. Drawing method. 8. The drawing method according to claim 7, further comprising: when the code amount of the intermediate code exceeds a capacity of the intermediate buffer, expanding the data of a portion written in the intermediate buffer to a drawing memory. Preceding, then writing the remaining overflow data to the intermediate buffer,
Developing this in a drawing memory and further combining it with the previously developed part; and when overflow occurs in the intermediate buffer, the attribute information specified immediately before the overflow occurs in the second storage means. Storing the overflow data written into the intermediate buffer and, when starting the expansion from the head of the overflow data, specifying the attribute information stored in the second storage means as an initial value. How to draw. 9. A depiction according to any one of claims 1 to 6.
And a bit map developed in the drawing memory.
Print and record an image corresponding to the template data.
Printer. 10. The method according to claim 1, wherein
A drawing device, and a bitmap developed in the drawing memory.
Displaying an image corresponding to the backup data
Image display device.