JPH08216454A - Printer and character processing method in printer - Google Patents

Abstract

PURPOSE: To develop the same characters of different sizes for which print request is made at high speed without degrading and damaging print quality. CONSTITUTION: A CPU 2003 produces linear approximate data for characters of different sizes on the basis of linear approximate data stored in a cache memory 2007 and develops bit map fonts in a working memory 2008 on the basis of the produced linear approximate data, when a CPU 2003 judges that character sizes for which print request is made does not exceed a permissible magnification rate by checking externally-inputted control information against control data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus having a function of caching a scalable font in the form of linear approximation data and a character processing method for the printing apparatus.

[0002]

2. Description of the Related Art Conventionally, in this type of printing apparatus, when a character is printed, a cache search is performed. As a result, if the font data of the same font, the same character code and the same character size is not cached, it is scalable. The font data was referenced and recalculated to create linear approximation data.

[0003]

However, in the above-mentioned conventional example, it takes a long time to create the linear approximation data based on the scalable font data. Further, there is a problem that the quality deteriorates when the linear approximation data is expanded at a large expansion rate.

The present invention has been made to solve the above problems, and an object of the first to fourth inventions of the present invention is to create a linear approximation data based on scalable font data, and When expanding the linear approximation data for the same different character, if the print request character size is within the allowable scaling ratio, the already-cached linear approximation data for the same character is scaled to create the print request. Another object of the present invention is to provide a printing apparatus and a character processing method for the printing apparatus, which can perform high-speed expansion processing on the same characters having different character sizes without degrading the printing quality.

[0005]

According to a first aspect of the present invention, a font storage means for storing a scalable font and the scalable font stored in the font storage means are expanded into character-type linear approximation data. A first expanding means, a first storing means for temporarily storing the linear approximation data expanded by the first expanding means, and the linear approximation data temporarily stored in the first storing means are managed. Second storage means for storing management data, a magnification determining means for collating the control information with the management data to determine whether or not the character size requested for printing exceeds an allowable variable magnification, and the magnification determining means. Determines that the character size requested to be printed does not exceed the allowable scaling factor, a print request is made based on the linear approximation data stored in the first storage means. And data generating means for generating different linear approximation data of the character size, is provided with a second expansion means for expanding the bit map font based on the linear approximation data created by the data creating means.

According to a second aspect of the present invention, the magnification determining means determines whether or not the print-requested character size exceeds an allowable scaling factor threshold set for enlargement or reduction.

According to a third aspect of the present invention, the data creating means creates the linear approximation data having different sizes by scaling the coordinate values of the linear approximation data.

According to a fourth aspect of the present invention, in a character processing method of a printing apparatus for printing font data generated based on control information input from a higher-level device, a scalable font is converted into character-type linear approximation data. A first expanding step of expanding, a cache step of caching the expanded linear approximation data together with predetermined management data in a storage medium, and a character size requested to be printed by collating the control information with the management data. And the control data and the management data are collated when it is determined that the character size requested to be printed does not exceed the allowable scaling ratio by the scaling determination step. A data creation step of creating linear approximation data of different sizes based on the cached linear approximation data, and And it has a second expansion step of deploying the bit map font based on the linear approximation data.

[0009]

In the first aspect of the invention, the magnification determining means for comparing the control information with the management data to determine whether or not the print-requested character size exceeds the allowable scaling factor causes the print-requested character size to vary. When it is determined that the magnification is not exceeded, the data creating means creates the linear approximation data of different character sizes requested to be printed based on the linear approximation data stored in the first storage means, and the created data is created. The second expanding means expands the bitmap font on the basis of the straight-line approximation data, and can quickly develop a font having a different size from the cached straight-line approximation data without deteriorating the character quality. .

In the second aspect of the present invention, the scaling factor determination means has a scaling factor derived from the print-requested character size and the cached character size exceeding an allowable scaling factor threshold set for enlargement or reduction. Determine whether or not
It is possible to limit the font expansion that significantly reduces the character quality.

In the third invention, the data creating means is
It is possible to expand the font data of the size requested for printing at high speed by scaling the coordinate values of the linear approximation data to create linear approximation data of different sizes.

In the fourth aspect of the present invention, the scalable font is expanded into character type linear approximation data, and the expanded linear approximation data is cached in a storage medium together with predetermined management data. When it is determined that the character size requested to be printed does not exceed the allowable scaling factor by the scaling factor determination, it is determined whether the character size requested to be printed exceeds the allowable scaling factor. Creates linear approximation data of different sizes based on the cached linear approximation data by collating with the management data, and develops a bitmap font based on the created linear approximation data,
This makes it possible to perform a programmable process of expanding fonts of different sizes from cached straight line approximation data without degrading the character quality.

[0013]

FIG. 1 is a sectional view showing the internal structure of a laser beam printer (hereinafter abbreviated as LBP) applied to this embodiment. This LBP is for registering a character pattern from a data source (not shown) and a fixed format ( You can register (form data) etc.

In the figure, reference numeral 1000 denotes an LBP main body, which is an externally connected host computer 2001.
Character information (character code) supplied from (see FIG. 2), form information, macro commands, etc. are input and stored, and corresponding character patterns, form patterns, etc. are created in accordance with these information, and are recording media. An image is formed on the recording paper. Reference numeral 1012 denotes a scanning panel in which switches for operation and an LED display are arranged,
A printer control unit 1001 controls the entire LBP 1000 and analyzes character information and the like supplied from the host computer. This printer control unit 10
01 mainly converts the character information into a video signal of a corresponding character pattern and outputs it to the laser driver 1002.

The laser driver 1002 is a semiconductor laser 1
This is a circuit for driving 003, and switches on and off the laser light 1004 emitted from the semiconductor laser 1003 according to the input video signal. Laser light 100
A rotary polygon mirror 1005 is swung in the left-right direction to scan the electrostatic drum 1006. As a result, the electrostatic drum 100
A character pattern electrostatic latent image is formed on 6. The latent image is developed by the developing unit 1007 around the electrostatic drum 1006 and then transferred to the recording paper.

A cut sheet is used as the recording sheet, and the cut sheet recording sheet is stored in a sheet cassette 1008 mounted on the LBP1000, and is taken into the apparatus by a sheet feeding roller 1009 and conveying rollers 1010 and 1011 to be electrostatically charged. It is supplied to the drum 1006.

FIG. 2 is a block diagram for explaining the control arrangement of the printing apparatus showing the embodiment of the present invention.

In the figure, reference numeral 2000 denotes a printer main body, which is connected to a host computer 2001 via an interface cable. An input interface unit 2002 receives print data transferred from the host computer 2001. A CPU 2003 sequentially executes the control programs stored in the program ROM 2004.

A font ROM 2005 stores scalable font data. Reference numeral 2006 denotes a panel operation unit. Reference numeral 2007 denotes a cache memory, which is used to temporarily store character-type linear approximation data generated from the scalable font data. 200
A work memory 8 is used as a work area or the like when the CPU 2003 executes a program.

The work memory 2008 also includes a frame buffer for storing an output image. 2009
Is an output interface unit, which converts the data in the frame buffer into a video signal and transfers it to the print engine unit. Reference numeral 2010 denotes a print engine unit that actually prints out.

Correspondence between this embodiment and each means of the first to third inventions and their functions will be described below with reference to FIG.

A first aspect of the present invention is a font storage means for storing a scalable font in a printing device (printer main body 2000) for printing font data generated based on control information input from a host device (host computer 2001). (Font ROM 2004) and a first expansion means (CPU 2003 for expanding the scalable font stored in the font storage means into character-type linear approximation data based on the expansion processing program stored in the program ROM 2004). )
And first storage means for temporarily storing the linear approximation data expanded by the first expansion means, and management data for managing the linear approximation data temporarily stored in the first storage means. Second storage means (work memory 2
008) and the control information and the management data to check whether or not the character size requested for printing exceeds a permissible scaling factor (CPU 2003 based on a scaling factor determination program stored in the program ROM 2004). And the magnification determining means determines that the character size requested to be printed does not exceed the allowable variable magnification, the printing request is made based on the linear approximation data stored in the first storage means. Data creating means (CPU 200) for creating linear approximation data having different character sizes
3 is means for creating based on the creating program stored in the program ROM 2004), and second expanding means (CPU 20) for expanding the bitmap font based on the linear approximation data created by the data creating means.
03 is provided to expand based on the expansion processing program stored in the program ROM 2004), and the control information is collated with the management data to determine whether the print-requested character size exceeds the allowable scaling ratio. CPU2
003 determines that the character size requested for printing does not exceed the allowable scaling factor, the CPU 2003 based on the straight line approximation data stored in the cache memory 2007.
Creates linear approximation data having different character sizes requested to be printed, the CPU 2003 develops a bitmap font based on the created linear approximation data,
It enables high-speed expansion of fonts of different sizes from cached straight-line approximation data without degrading the character quality.

According to a second aspect of the present invention, the scaling factor determining means has a scaling factor derived from the print-requested character size and the cached character size exceeding an allowable scaling factor threshold set for enlargement or reduction. It is possible to determine whether or not it is possible to limit the font expansion that causes the character quality to be significantly reduced.

According to a third aspect of the invention, the data creating means scales the coordinate values of the linear approximation data to create linear approximation data of different sizes, and develops font data of a size requested to be printed at high speed. Is possible.

FIG. 3 is an explanatory view showing an outline of a character processing state in the printing apparatus according to the present invention.

In the figure, 3000 is scalable font data. In the character scaling processing, the linear font approximation data 3001 is generated by referring to the scalable font data 3000, and the bitmap 3002 is generated based on the linear approximation data 3001. The bitmap 3002 is expanded in the frame buffer.
The linear approximation data 3001 once generated is stored in the cache memory 3003.

Next, when printing characters of the same font and the same character code but different sizes, the cache memory 3
The linear approximation data 3004 stored in 003 is referred to, and the linear approximation data is enlarged / reduced to generate linear approximation data 3005 having a target size.

Further, a bit map 3006 is generated on the basis of the straight line approximation data 3005 and developed in the frame buffer.

FIG. 4 is a diagram for explaining a processing state for generating a bitmap from straight line approximation data in the printing apparatus according to the present invention.

In the figure, straight line approximation data 4000 is a set of point information 4002. The point information is composed of coordinate information (dot unit) and identifiers of start point, intermediate point, and end point. A bitmap 4001 is generated by linear interpolation from the point coordinates of the linear approximation data.

FIG. 5 is an explanatory view showing a processing state of enlarging / reducing straight line approximation data in the printing apparatus according to the present invention.

In the figure, target linear approximation data 5001 is generated by multiplying the coordinate value 5002 of each point of the linear approximation data 5000 by the enlargement / reduction ratio. FIG. 5 shows the case of 200% enlargement. 5003 is linear approximation data 500
It is a coordinate value of 1.

FIG. 6 is a diagram showing the structures of a cache memory for storing the linear approximation data and a cache table for managing the cache memory in the printing apparatus according to the present invention.

In the figure, a cache table 6000
One entry is composed of a font ID unique to the font, a character code, a character size, and a pointer pointing to a data storage area. The data for one character in the cache memory 6001 is a set of point information for the linear approximation data composed of the data size indicating the data size for one character and the linear approximation data, and one point information is a start point and an end point. It is composed of an identifier indicating one of a point and an intermediate point, and X and Y coordinates.

The print processing operation of the printing apparatus of the present invention will be described below with reference to the flow chart shown in FIG.

FIG. 7 is a flow chart showing an example of the print processing procedure in the printing apparatus according to the present invention. In addition,
(1) to (8) show each step.

If there is data input while waiting for data input in step (1), the process proceeds to step (2), and if there is no data input, the process returns to step (1).

In step (2), the data transferred from the host is read, and in step (3), data analysis is performed.

In step (4), as a result of the data analysis, if it is judged that it is the paper discharge command, the process proceeds to step (5), and if it is judged that it is not the paper discharge command, the process proceeds to step (8).

In step (5), the contents of the frame buffer are converted into a video signal and the print engine 2010
Transfer to. Next, in step (6), the print engine unit 2010 actually prints. Step (7)
Then, discharge the paper.

On the other hand, if NO in step (4), the flow proceeds to step (8) to execute a character processing routine described later.

FIG. 8 is a flow chart showing the detailed procedure of the character processing routine of the printing apparatus of the present invention, which corresponds to the character processing method of the printing apparatus according to the present invention. In addition, (1) ~
(9) shows each step.

In step (1), the cache table is searched using the font ID, character size, and character code as keys. As a result of the search, in step (2), it is determined whether or not data with the same font and the same character code exists, and if it is determined that there is data with the same font and the same character code, step (3) ), And if it does not exist, proceed to (8).

In step (3), it is judged whether or not there is data of the same font and the same character code and the same character size. If there is data of the same font and the same character code and the same character size, go to step (9). Then, referring to the corresponding data in the cache memory, the process returns to step (6).

On the other hand, when it is determined in step (3) that data of the same font, the same character code and the same character size does not exist, the process proceeds to step (4), and the character size of the character to be printed and the cache memory The character size of the data of the same character code in the same font is compared, and it is determined whether the enlargement ratio is M% or more (8). If it is determined that the enlargement ratio is M% or more, go to step (8). Then, the linear approximation data of the character size to be newly printed is generated from the scalable font data, and the process returns to step (6).

On the other hand, if it is determined in step (4) that it is less than M%, the process proceeds to step (5) to enlarge / reduce the linear approximation data of the same character code and the same character code in the cache to obtain the target. Generate linear approximation data for size.

Then, in step (6), a bit map is generated based on the linear approximation data. In step (7), the bitmap is expanded in the designated area of the frame buffer, and the character processing ends.

Correspondence between the present embodiment and each step of the fourth invention and its action will be described below with reference to FIG.

A fourth aspect of the present invention is a character processing method for a printing apparatus, which prints font data generated based on control information input from a higher-level device, wherein a scalable font is expanded into character-type linear approximation data. Expansion step (preprocessing of step (1) in FIG. 8), a cache step (step (1) in FIG. 8) for caching the expanded straight line approximation data together with predetermined management data in the storage medium, A magnification determination step of comparing the control information with the management data to determine whether the character size requested for printing exceeds the allowable scaling ratio (step (4) in FIG. 8).
If the character size requested to be printed does not exceed the allowable variable ratio by the scaling factor determination, the control information and the management data are collated with each other to have a different size based on the cached linear approximation data. A data creating step (step (5) in FIG. 8) of creating straight line approximation data and a second expanding step (step (6) of FIG. 8) of expanding a bitmap font based on the created straight line approximating data. ) And, it is possible to programmably execute the process of rapidly expanding fonts of different sizes from cached linear approximation data without degrading the character quality. [Other Embodiments] In this embodiment, when the character data of the same font and the same character code exists in the cache, the scaling factor used when comparing the character size of the cached data with the target character size. The threshold value M is not a fixed value but may be configured so that a desired threshold value M can be designated by a designating means provided in the panel operation section.

Further, in the above embodiment, the case where the vertical / horizontal equal magnification is enlarged / reduced only by the character size has been described. You may.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0052]

As described above, the first aspect of the present invention
According to the invention, the magnification determining means for determining whether the character size requested for printing exceeds the allowable scaling ratio by collating the control information with the management data, and the character size requested for printing must not exceed the allowable scaling ratio. When the determination is made, the data creating means creates linear approximation data of different character sizes requested to be printed based on the linear approximation data stored in the first storage means, Since the second expanding means expands the bitmap font based on the above, fonts of different sizes can be expanded at high speed from the cached straight-line approximation data without deteriorating the character quality.

According to the second aspect of the present invention, the scaling factor determining means sets the allowable scaling factor threshold value in which the scaling factor derived from the character size requested for printing and the cached character size is set to enlargement or reduction. Since it is determined whether or not the font quality exceeds, it is possible to restrict the font expansion that causes the character quality to be significantly deteriorated.

According to the third invention, the data creating means comprises:
Since the linear approximation data having different sizes are created by scaling the coordinate values of the linear approximation data, the font data of the size requested for printing can be developed at high speed.

According to the fourth aspect of the invention, the scalable font is expanded into character type linear approximation data, and the expanded linear approximation data is cached in a storage medium together with predetermined management data. If the character size requested for printing exceeds the allowable scaling ratio by collating with the management data, and if it is determined by the scaling ratio determination that the character size requested for printing does not exceed the allowable scaling ratio, the above control is performed. Since the linear approximation data having different sizes are created based on the linear approximation data cached by collating the information and the management data, the bitmap font is developed based on the created linear approximation data. A process to quickly develop fonts of different sizes from cached linear approximation data without degrading the character quality It can be executed in Guramaburu.

Therefore, the same characters having different character sizes requested for printing can be developed at high speed without deteriorating the printing quality.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the internal structure of a laser beam printer applied to this embodiment.

FIG. 2 is a block diagram illustrating a control configuration of a printing apparatus according to an exemplary embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an outline of a character processing state in the printing apparatus according to the present invention.

FIG. 4 is a diagram illustrating a processing state in which a bitmap is generated from linear approximation data in the printing apparatus according to the present invention.

FIG. 5 is an explanatory diagram showing a processing state of enlargement / reduction of linear approximation data in the printing apparatus according to the present invention.

FIG. 6 is a diagram showing a structure of a cache memory that stores linear approximation data and a cache table that manages the cache memory in the printing apparatus according to the present invention.

FIG. 7 is a flowchart illustrating an example of a print processing procedure in the printing apparatus according to the present invention.

FIG. 8 is a flowchart showing a detailed procedure of a character processing routine of the printing apparatus of the present invention.

[Explanation of symbols]

 2003 CPU 2004 Program ROM 2005 Font ROM 2007 Cache memory 2008 Work memory

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Claims (4)

[Claims] 1. In a printing apparatus for printing font data generated based on control information input from a higher-level device, a font storage unit for storing a scalable font and the scalable font stored in the font storage unit are provided. The first to develop into character type linear approximation data
Expansion means, first storage means for temporarily storing the linear approximation data expanded by the first expansion means, and management data for managing the linear approximation data temporarily stored in the first storage means. A second storage means for storing the information, a magnification determination means for collating the control information with the management data to determine whether the character size requested for printing exceeds an allowable variable magnification, and the magnification determination means for printing. Data for creating straight-line approximation data of different print-requested character sizes based on the straight-line approximation data stored in the first storage means when it is determined that the requested character size does not exceed the allowable scaling factor. A mark comprising: a creating unit and a second expanding unit that expands a bitmap font based on the straight line approximation data created by the data creating unit. Apparatus. 2. The magnification determining means determines whether or not the character size requested for printing exceeds a permissible scaling factor threshold set for enlargement or reduction. The printing device described. 3. The printing apparatus according to claim 1, wherein the data creating means scales the coordinate values of the linear approximation data to create linear approximation data of different sizes. 4. A character processing method of a printing device for printing font data generated based on control information input from a higher-level device, comprising a first expanding step of expanding a scalable font into character-type linear approximation data. A cache step of caching the expanded linear approximation data in a storage medium together with predetermined management data, and whether the character size requested for printing exceeds the allowable scaling ratio by collating the control information with the management data. And a linear approximation data cached by collating the control information with the management data when it is determined that the character size requested to be printed does not exceed the allowable variable magnification by the magnification determination step A data creation step of creating linear approximation data of different sizes based on the above, and based on the created linear approximation data A character processing method for a printing apparatus, comprising a second expanding step of expanding a bitmap font.