JP2004126939A - Picture forming device and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a picture forming device and its control method by which various rendering processing are available. <P>SOLUTION: The curve portion of a graphic provided by a rendering instruction in print data is provided with straight-line fitting with a first smoothness. The curve shape of the graphic at its line tip portion is provided with the straight-line approximating with a second smoothness. Where, the first smoothness and the second smoothness are separately specified. In addition, the curve shape of the graphic at its line connection portion is provided with the straight-line approximating with a separate specification-allowed third smoothness. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus and a control method thereof, and more particularly, to a drawing process in an image forming apparatus based on print data described in a page description language.
[0002]
[Prior art]
In an image forming apparatus that forms an image based on print data described in a page description language, if a figure given by a drawing command in supplied print data includes a curved portion, the image data is specified in the print data. The straight line approximation of the curve portion is performed with the given smoothness.
[0003]
On the other hand, when the shape of the leading end of each line of the figure is an arc, or when the shape of the connecting portion between the lines is rounded, the straight line approximation for the curve is performed for the curved part in the above figure. This is performed with the smoothness or the smoothness previously set in the image forming apparatus.
[0004]
[Problems to be solved by the invention]
However, if the shape of the end of a line or the shape of the connection between lines is curved by linear approximation using the smoothness for the figure curve part as described above, unexpected drawing results may occur depending on the type of page description language. Was sometimes obtained.
[0005]
Also, when the shape of the tip of each line or the shape of the connecting portion between lines is curved by linear approximation using a smoothness preset in the image forming apparatus, the specifications are defined depending on the type of page description language. There is a problem that the output is not guaranteed.
[0006]
The present invention has been made in view of such a problem, and has as its object to provide an image forming apparatus capable of performing various drawing processes and a control method thereof.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, for example, an image forming apparatus of the present invention has the following configuration. That is, an image forming apparatus for forming an image based on print data described in a page description language, wherein a curve portion of a graphic given by a drawing command in the print data is linearly approximated by a first smoothness. A first approximation unit, and a second approximation unit for linearly approximating the curve shape of the line tip of the figure with a second smoothness, wherein the first and second smoothnesses are respectively different from each other. It can be designated as.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
[0009]
A configuration example of a laser beam printer will be described as an example of an image forming apparatus to which an embodiment of the present invention can be applied. Note that the present embodiment is applicable not only to a laser beam printer but also to other types of image forming apparatuses such as an inkjet printer and an MFP (Multi Function Printer).
[0010]
FIG. 1 is a block diagram illustrating a configuration of the image forming apparatus according to the embodiment.
[0011]
In FIG. 1, reference numeral 102 denotes a laser beam printer (hereinafter, simply referred to as “printer”). Reference numeral 101 denotes a data processing device, for example, a computer, which functions as a supply source of print data or a control device of the printer 102.
[0012]
The printer 102 includes a printer controller 103, a panel unit 104, and a printer engine 105 as illustrated.
[0013]
The printer controller 103 generates bitmap data for each page based on print data described in a page description language (hereinafter, referred to as “PDL”) supplied from the data processing apparatus 101, and generates the bitmap data. The data is sent to the printer engine 105.
[0014]
The printer engine 105 forms a latent image on a photosensitive drum based on the bitmap data supplied from the printer controller 103, and transfers and fixes the latent image on a recording medium according to a so-called electrophotographic method, thereby forming an image. Record.
[0015]
The panel unit 104 is used as a user interface. By operating the panel unit 104, the user can instruct a desired operation. The panel unit 104 displays processing contents of the printer 102 and warning contents to the user.
[0016]
FIG. 2 is a diagram illustrating a configuration of the printer 102.
[0017]
In the figure, reference numeral 201 denotes a printer housing; 202, an operation panel on which a switch for giving various instructions by a user, an LED display, an LCD display, and the like for displaying messages, printer settings, and the like are arranged; This corresponds to the panel unit 104 shown in FIG. Reference numeral 203 denotes a board accommodating unit, which accommodates a board constituting an electronic circuit portion of the printer controller 103 and the printer engine 105.
[0018]
Reference numeral 220 denotes a paper cassette for holding the paper (recording medium) S, and has a mechanism for electrically detecting the paper size by a partition plate (not shown). Reference numeral 221 denotes a cassette clutch, which takes out the topmost sheet of the paper S placed on the paper cassette 220 and transfers the taken out paper S to the paper feed roller 222 by a driving force transmitted from a driving unit (not shown). It has a cam to transport. This cam rotates intermittently each time paper is fed, and feeds one sheet of paper S corresponding to one rotation. A sheet detection sensor 223 detects the amount of the sheet S held in the sheet cassette 220.
[0019]
The paper feed roller 222 is a roller that conveys the leading end of the paper S to the registration shutter 224. Reference numeral 224 denotes a registration shutter, which can stop paper feeding by pressing the paper S. 230 is a manual feed tray, and 231 is a manual feed clutch. The manual paper feed clutch 231 is used to transport the leading edge of the paper S to the manual paper feed roller 232, and the manual paper feed roller 232 is used to transport the leading edge of the paper S to the registration shutter 224. The sheet S to be used for image recording is fed by selecting one of the sheet feeding means of the sheet cassette 220 and the manual feed tray 230.
[0020]
The printer engine 105 communicates with the printer controller 103 according to a predetermined communication protocol, selects one of the paper cassettes 220 from the manual feed tray 230 according to an instruction from the printer controller 103, and issues a print start instruction. The sheet S is conveyed from the corresponding sheet feeding means to the registration shutter 224 in accordance with. As described above, the printer engine 105 includes a paper feeding unit, a mechanism related to an electrophotographic process such as formation, transfer, and fixing of a latent image, a paper discharging unit, and a control unit therefor.
[0021]
Reference numerals 204a, 204b, 204c, and 204d denote image recording units having photosensitive drums 205a, 205b, 205c, and 205d and a toner holding unit, respectively, and form a toner image on the paper S by an electrophotographic process. On the other hand, reference numerals 206a, 206b, 206c, and 206d denote laser scanner units, which supply image information using laser beams to corresponding image recording units.
[0022]
In the image recording units 204a, 204b, 204c, and 204d, a paper transport belt 250 that transports the paper S is stretched flat by a plurality of rotating rollers 251 to 254 in the paper transport direction (upward from the bottom in the figure). In the most upstream portion, the paper is electrostatically attracted to the paper transport belt 250 by the attracting roller 225 to which the bias is applied. Also, four photosensitive drums 205a, 205b, 205c, 205d are arranged linearly in opposition to the belt conveying surface, and constitute an image forming means. In each of the image recording units 204a, 204b, 204c, and 204d, a charger and a developing device are arranged so as to sequentially surround the periphery of the photosensitive drum.
[0023]
Reference numerals 207a, 207b, 207c, and 207d denote laser units in the laser scanner units 206a, 206b, 206c, and 206d, respectively, which drive a built-in semiconductor laser according to an image signal (/ VIDEO signal) sent from the printer controller 103. And emits a laser beam. The laser beams emitted from the laser units 207a, 207b, 207c, 207d are respectively scanned by polygon mirrors (rotating polygon mirrors) 208a, 208b, 208c, 208d, and latent images are formed on the photosensitive drums 205a, 205b, 205c, 205d. Form.
[0024]
Reference numeral 260 denotes a fixing unit that thermally fixes the toner image formed on the sheet S by the image recording units 204a, 204b, 204c, and 204d onto the recording sheet S. A transport roller 261 discharges and transports the sheet S. A paper discharge sensor 262 detects the paper discharge state of the paper S. Reference numeral 263 denotes a paper discharge roller and a conveyance path switching roller for double-sided printing. The paper S is conveyed in the paper discharge direction. In the case of conveyance, the sheet S is conveyed to the conveyance path 270 for double-sided printing by changing the rotation direction to the opposite direction immediately after the rear end of the sheet S passes the sheet ejection sensor 262 and performing switchback. Reference numeral 265 denotes a discharged paper stacking amount detection sensor which detects the stacked amount of the paper S stacked on the discharge tray 264.
[0025]
Reference numeral 270 denotes a conveyance path for double-sided printing. The sheet S conveyed for double-sided printing by the discharge roller / double-sided printing conveyance path switching roller 263 is conveyed again to the registration shutter 224 by the double-sided conveyance rollers 271 to 274 to form an image. It waits for a transport instruction to the recording units 204a, 204b, 204c, 204d.
[0026]
The printer 102 can be further provided with optional units such as an optional cassette and an envelope feeder.
[0027]
Next, the configuration of the printer controller 103 will be described with reference to FIG.
[0028]
The printer controller 103 includes an input buffer (not shown) for inputting print data transmitted from the data processing apparatus 101 and settings for instructing operation of the apparatus, and an output including a signal transmitted to the data processing apparatus 101 and device information data. It has a host interface (I / F) unit 302 provided with an output buffer (not shown) for temporarily holding data, and the host I / F unit 302 is exchanged with the data processing device 101. It configures an input / output unit for signals and communication packets, and controls communication with the data processing device 101.
[0029]
Print data described in PDL input via the host I / F unit 302 is provided to the image data generation unit 303. The image data generation unit 303 analyzes the input print data (for example, PDL analysis processing), generates a drawing object as an intermediate language from the analysis result, and further generates bitmap data that can be processed by the printer engine 105. . Specifically, the print data is analyzed and the object information is created by the analysis, and the rasterizing process is performed in parallel with the creation of the object information. In the rasterizing process, the display colors RGB (additive color mixture) included in the print data are converted into YMCK (subtractive color mixture) that can be processed by the printer engine. Performs conversion to font data such as fonts, creates bitmap data in page units or band units, performs pseudo gradation processing using a dither pattern on this bitmap data, and enables printing processing in the printer engine Generate bitmap data.
[0030]
The created bitmap data is stored in the image memory 305. The reading of the bitmap data stored in the image memory 305 is controlled by the DMA control unit 308, and the control of the reading of the bitmap data from the image memory 305 by the DMA control unit 308 is performed based on an instruction from the CPU 309.
[0031]
The bitmap data read from the image memory 305 is transferred to the engine 105 as a video signal via the engine I / F unit 306. The engine I / F unit 306 includes an output buffer (not shown) for temporarily holding a video signal to be transferred to the engine 105, and an input buffer (not shown) for temporarily holding a signal sent from the engine 105. ) Are provided, and the engine I / F unit 306 constitutes an input / output unit of a signal exchanged with the engine 105 and controls communication with the engine 105.
[0032]
An instruction related to mode setting or the like issued by an operation input from the panel unit 104 (see FIG. 1) is input via the panel I / F unit 301, and the panel I / F unit 301 operates between the panel unit 104 and the CPU 309. (Instructions to the printer, such as a mode setting issued by an operation input, can also be issued via the host I / F unit 302 that performs bidirectional communication with the data processing apparatus 101.)
[0033]
The CPU 309 controls each block described above according to the mode instructed from the panel unit 104 or the data processing device 101, and this control is executed based on a control program stored in the ROM 304. The control program stored in the ROM 304 includes an OS (Operating System) for performing time-division control on a load module basis called a task by a system clock, and a plurality of load modules executed and controlled on a function basis by the OS. It is composed of The control program including the load module is stored in an EEPROM (non-volatile memory) 310 as needed.
[0034]
The RAM 307 is used as a work area for the arithmetic processing by the CPU 309. Each block including the CPU 309 is connected to the system bus 320. The system bus 320 includes an address bus and a system bus.
[0035]
FIG. 4 is a diagram showing a processing path of input data in the printer controller 103 for each functional block.
[0036]
Print data input from the data processing device 101 via the host I / F unit 302 is input to the image data generation unit 303. The print data input to the image data generation unit 303 is subjected to command analysis by a PDL analysis unit (303a), then generated as a drawing object (intermediate language) by a drawing object generation unit (303b), and stored in a work memory on a RAM 307. Recorded temporarily.
[0037]
Then, the drawing memory is read from the working memory on the RAM 307 at any time and rasterized (303 c), and the image data finally recorded on the recording medium is developed into a bitmap image and stored in the image memory 305, and the engine I / F unit 306 And output to the recording medium.
[0038]
Now, in an image forming apparatus that forms an image based on print data described in a page description language, conventionally, when a figure given by a drawing command in supplied print data includes a curved portion, With the smoothness specified in the print data, a straight line approximation of the curve portion is performed. FIG. 10 is a diagram illustrating a state of such a linear approximation. The curve portion of the path graphic given by the drawing command is represented by an approximate curve as shown. Further, the smoothness here indicates a distance between an ideal curve and an approximate curve as shown in the figure.
[0039]
On the other hand, in the conventional image forming apparatus, as described above, when the shape of the leading end of each line of the figure is an arc shape, or when the shape of the connecting portion between the lines is rounded, The straight line approximation has been performed with the smoothness for straight line approximation of the curved portion of the figure or the smoothness preset in the image forming apparatus.
[0040]
Before describing the graphic drawing processing in the embodiment, the conventional graphic drawing processing as described above will be described in detail.
[0041]
FIG. 5 is a flowchart showing a conventional graphic drawing process.
[0042]
First, when the print data input via the host I / F and analyzed by the PDL analysis unit is a graphic drawing command, the smoothness for linear approximation of a curved portion in the path graphic (for example, included in the graphic drawing command) ) (Step S501), and a straight line approximation of the curved portion of the path graphic is performed with the given smoothness (step S502).
[0043]
Next, it is determined whether or not the details of the graphic drawing command are line drawing commands (step S503). If the command is not a line drawing command (for example, if it is a fill drawing command), the straight line data generated in step S502 is The bitmap data generation process (step S506) is performed, and the process ends. Specifically, in step S506, it is determined whether or not the closed area surrounded by the approximate straight line generated in step S502 overlaps with the area on the grid that divides the print surface into pixels. It is determined that black and non-overlapping pixels are white, and bitmap data is generated as output data to the printer engine.
[0044]
On the other hand, if it is determined in step S503 that the command is a line drawing command, reference is made to setting information (for example, line width, broken line shape, tip shape, line connection shape, etc.) necessary for line generation processing (step S504). Then, an outline generation process is performed (step S505). At this time, in the outline generation processing, the closed area for forming the line is determined according to the setting information such as the line width, the tip shape, and the line connection shape. However, the tip shape of each line and the shape of the connection part between the lines (line When generating the connection shape), the smoothness for the curved part in the path graphic referred to in step S501 is used. Then, a bitmap data generation process is performed (step S506), and the process ends.
[0045]
The above is the conventional graphic drawing process. As described above, in the conventional image forming apparatus, as described above, the shape of the tip of each line is obtained by the linear approximation using the smoothness for the curved portion in the path graphic as described above. When the line connection shape is curved, an unexpected drawing result may be obtained depending on the type of the page description language. Also, when the shape of the tip of each line or the shape of the connecting portion between lines is curved by linear approximation using a smoothness preset in the image forming apparatus, the specifications are defined depending on the type of page description language. There is a problem that the output is not guaranteed.
[0046]
The present invention improves this point, and the graphic drawing processing in the embodiment will be described in detail below.
[0047]
FIG. 6 is a flowchart illustrating the graphic drawing processing according to the embodiment. A program corresponding to this flowchart is stored in the ROM 304 as a control program, loaded into the RAM 307, and executed by the CPU 309.
[0048]
First, when the print data input via the host I / F 302 and analyzed by the PDL analysis unit 303a is a graphic drawing command, the first smoothness for a curved portion in the path graphic (for example, included in the graphic drawing command) (Step S 601), and a straight line approximation of a curved portion in the path graphic is performed with the given first smoothness (step S 602).
[0049]
Next, it is determined whether or not the details of the graphic drawing command are a line drawing command (step S603). If the command is not a line drawing command (for example, if it is a fill drawing command), the approximate straight line generated in step S602 is determined. Is generated (step S608), and the graphic drawing processing ends. Specifically, in step S608, it is determined whether or not the closed area surrounded by the approximate straight line generated in step S602 overlaps with the area on the grid that divides the print surface into pixels. It is determined that black and non-overlapping pixels are white, and bitmap data is generated as output data to the printer engine.
[0050]
On the other hand, if it is determined in step S603 that the command is a line drawing command, reference is made to setting information (for example, line width, broken line shape, tip shape, line connection shape, etc.) necessary for line generation processing (step S604). Then, it is determined whether a curved figure (such as a circle) is designated as the tip shape (step S605). If no curve is specified for the tip shape, outline generation processing (step S607) is performed according to the setting information referred to in step S604, then bitmap data generation processing (step S608) is performed, and the graphic drawing processing ends.
[0051]
On the other hand, if a figure including a curve is designated as the tip shape in step S605, the second smoothness for linear approximation of the tip shape is referred to (step S606). The second smoothness for the tip shape is included in, for example, a line drawing command, and can be specified separately from the first smoothness for a curved portion in the above-described path graphic.
[0052]
After that, outline generation processing is performed (step S607). In this outline generation processing, the closed area for forming the line is determined according to the setting information such as the line width, the tip shape, and the connection point shape. However, the tip shape is the second shape for the tip shape referred to in step S606. A curve is formed by linear approximation using smoothness. Then, bitmap data generation processing is performed (step S608), and the processing ends.
[0053]
In the above processing, the tip shape of the line is curved by linear approximation using the second smoothness for the tip shape, which can be specified separately from the first smoothness for the curved portion in the path graphic. Further, the third smoothness for the line connection shape may be separately specified, and the line connection shape may be curved by linear approximation.
[0054]
FIG. 7 is a flowchart showing a graphic drawing process in which a third smoothness for a line connection shape is separately specified, and the line connection shape is curved by linear approximation.
[0055]
The processing contents shown in this flowchart are almost the same as the processing contents shown in the above-mentioned flowchart of FIG. 6, and in the flowchart of FIG. 7, the same reference numerals are given to the same processing steps as the processing steps in the flowchart of FIG. Is attached. The difference is that, in the processing of FIG. 7, between steps S606 and S607, it is determined whether or not a curved figure (such as a circle) is designated as the line connection shape, and the determination results of step S701 are yes. Is that a step S702 of referring to the third smoothness for line connection shape straight line approximation is added in the case of. The third smoothness is included in, for example, a line drawing command. The first smoothness for the curved portion in the path graphic and the second smoothness for the tip of the line are respectively described above. It can be specified separately.
[0056]
When the third smoothness is referred to in step S702, in the next step S607, the shape of the connecting portion between the lines is curved by linear approximation using the third smoothness.
[0057]
FIG. 9 is a diagram illustrating an example of a processing result of the graphic drawing processing according to the flowchart of FIG. 7 described above. As shown in the drawing, the tip of the line of the path graphic is curved by linear approximation based on the second smoothness, and the shape of the line connecting portion is curved by linear approximation based on the third smoothness.
[0058]
As described above, according to the present embodiment, the curve shape of the line tip of the path graphic can be specified separately from the first smoothness for the curve of the path graphic. The linear shape is approximated by the smoothness of, and the curved shape of the connecting portion between the lines is linearly approximated by the third smoothness that can be specified separately from the first and second smoothnesses. Accordingly, various drawing processes can be realized, and an unexpected drawing result is not obtained. Then, it is possible to guarantee the output specified in the specification of the page description language.
[0059]
By the way, since the above-described second smoothness and third smoothness are included in the drawing command in the print data, it is determined whether the second and third smoothness can be designated. It depends on the specification of page description language (PDL). Therefore, the smoothness of the linear approximation of the curve shape of the line tip or the connection portion may be set according to the type of the PDL to be used.
[0060]
For example, a smoothness utilization list having a structure as shown in FIG. 11 is stored in the filter M304, for example. In FIG. 11, for PDL types A, B, and C, smoothness for path graphic processing (first smoothness), smoothness for tip shape straight line approximation (second smoothness), line connection shape straight line For each of the approximation smoothness degrees (third degree of approximation), settable information (settable is indicated by 、, settable not indicated by x), set values when settable, and initial values are described. . According to the example of FIG. 11, in the case of the printer description language A, any of the first, second, and third smoothnesses can be set. In the printer description language B, only the first smoothness can be set. It will be understood that the third smoothness cannot be set in the case of the printer description language C.
[0061]
Then, in the graphic drawing processing, the type of the PDL is determined, and the smoothness corresponding to the type of the PDL is obtained with reference to the above-described list of use of the smoothness.
[0062]
FIG. 8 is a flowchart illustrating an example of a graphic drawing process for setting the smoothness of the linear approximation of the curved shape of the line tip or the connection portion according to the type of PDL to be used.
[0063]
First, when the print data input via the host I / F 302 and analyzed by the PDL analysis unit 303a is a graphic drawing command, the first smoothness for a curved portion in the path graphic (for example, included in the graphic drawing command) Is performed (step S801), and the linearized approximation of the curve portion in the path graphic is performed with the given first smoothness (step S802).
[0064]
Next, it is determined whether or not the details of the graphic drawing command are a line drawing command (step S803). If the command is not a line drawing command (for example, if it is a fill drawing command), the approximate straight line generated in step S802 is determined. Is generated (step S816), and the graphic drawing process ends. Specifically, in step S816, it is determined whether or not the closed region surrounded by the approximate straight line generated in step S802 overlaps with the region on the grid that divides the print surface into pixels. It is determined that black and non-overlapping pixels are white, and bitmap data is generated as output data to the printer engine.
[0065]
On the other hand, if it is determined in step S803 that the command is a line drawing command, reference is made to setting information (for example, line width, broken line shape, tip shape, line connection shape, etc.) necessary for line generation processing (step S804). Then, the type of the PDL for executing the graphic drawing is confirmed (step S805). The type of PDL can be automatically determined from the given print data, for example. Next, a smoothness utilization list as shown in FIG. 11 is referred to (step S806).
[0066]
Then, it is determined whether or not a curved figure (such as a circle) is designated as the tip shape (step S807). If no curve is specified as the tip shape, the process proceeds to step S810, and from the smoothness utilization list, the tip shape straight line approximation smoothness (second smoothness) corresponding to the type of PDL confirmed in step S805. ), The process proceeds to step S811.
[0067]
On the other hand, if it is determined in step S807 that a figure including a curve has been specified as the tip shape, the process proceeds to step S808, and from the smoothness use list, the tip shape straight line approximation smoothness (corresponding to the type of PDL confirmed in step S805) It is determined whether (second smoothness) can be set. If the setting is possible, the corresponding setting value is referred to (step S809). If the setting is not possible, the corresponding initial value is referred to (step S810).
[0068]
Next, it is determined whether a curved figure (such as a circle) is designated as the line connection shape (step S811). Here, if no curve is specified for the line connection shape, the process proceeds to step S814, and from the list of smoothness utilization, the line connection shape straight line approximation smoothness (third degree) corresponding to the type of PDL confirmed in step S805. The process proceeds to step S815 with reference to the initial value of (smoothness).
[0069]
On the other hand, in step S811, if a figure including a curve is specified as the line connection shape, the process proceeds to step S812, and from the list of smoothness utilization, the line connection shape straight line approximation corresponding to the type of PDL confirmed in step S805. It is determined whether the degree (third smoothness) can be set. If the setting is possible, the corresponding setting value is referred to (step S813). If the setting is not possible, the corresponding initial value is referred to (step S814).
[0070]
Next, outline generation processing is performed (step S815). In this outline generation processing, a closed area for forming a line is determined according to setting information such as a line width, a tip shape, and a line connection shape. However, when generating a tip shape or a line connection shape of each line, step S809 is performed. , S810, S813 and S814 are used. Then, a bitmap data generation process (step S816) is performed, and the process ends.
[0071]
According to the above processing, it is possible to set the smoothness of the linear approximation of the curve shape of the line tip or the connection portion according to the type of the PDL used.
[0072]
(Other embodiments)
As described above, the embodiments of the present invention have been described in detail. However, the present invention may be applied to a system including a plurality of devices, or may be applied to an apparatus including a single device.
[0073]
According to the present invention, a software program (a program corresponding to the flowchart shown in any of FIGS. 6 to 8) for realizing the functions of the above-described embodiments is supplied directly or remotely to a system or apparatus, and This includes the case where the processing is also achieved by the computer of the apparatus reading and executing the supplied program code. In that case, the form does not need to be a program as long as it has the function of the program.
[0074]
Accordingly, since the functions of the present invention are implemented by computer, the program code installed in the computer also implements the present invention. That is, the claims of the present invention also include the computer program itself for implementing the functional processing of the present invention.
[0075]
In this case, any form of the program, such as an object code, a program executed by an interpreter, and script data supplied to the OS, is applicable as long as the program has the function of the program.
[0076]
As a recording medium for supplying the program, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card, ROM, DVD (DVD-ROM, DVD-R).
[0077]
In addition, as a method for supplying the program, a client computer connects to an Internet homepage using a browser, and downloads the computer program itself of the present invention or a compressed file including an automatic installation function to a recording medium such as a hard disk from the homepage. Can also be supplied. Further, the present invention can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. In other words, a WWW server that allows a plurality of users to download a program file for implementing the functional processing of the present invention on a computer is also included in the claims of the present invention.
[0078]
In addition, the program of the present invention is encrypted, stored in a storage medium such as a CD-ROM, distributed to users, and downloaded to a user who satisfies predetermined conditions from a homepage via the Internet to download key information for decryption. It is also possible to execute the encrypted program by using the key information and install the program on a computer to realize the program.
[0079]
The functions of the above-described embodiments are implemented when the computer executes the read program, and the OS or the like running on the computer executes a part of the actual processing based on the instructions of the program. Alternatively, the functions of the above-described embodiments can be realized by performing the entire process.
[0080]
Further, after the program read from the recording medium is written into the memory provided in the function expansion board inserted into the computer or the function expansion unit connected to the computer, the function expansion board or the A CPU or the like provided in the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are also realized by the processing.
[0081]
【The invention's effect】
According to the present invention, it is an object to provide an image forming apparatus capable of performing various drawing processes and a control method thereof. Can be.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of an image forming apparatus according to an embodiment.
FIG. 2 is a diagram illustrating a configuration of a printer according to the embodiment.
FIG. 3 is a diagram illustrating a configuration of a printer controller according to the embodiment.
FIG. 4 is a diagram illustrating a processing path of input data in a printer controller for each functional block.
FIG. 5 is a flowchart showing a conventional graphic drawing process.
FIG. 6 is a flowchart illustrating a graphic drawing process according to the embodiment.
FIG. 7 is a flowchart illustrating another example of a graphic drawing process according to the embodiment;
FIG. 8 is a flowchart illustrating another example of the graphic drawing process in the embodiment.
FIG. 9 is a diagram illustrating an example of a processing result of the graphic drawing processing according to the embodiment.
FIG. 10 is a diagram showing a state of linear approximation of a curved shape.
FIG. 11 is a diagram illustrating a structure example of a smoothness utilization list.

Claims (6)

An image forming apparatus that forms an image based on print data described in a page description language,
First approximation means for linearly approximating a curve portion of a graphic given by a drawing command in the print data with a first smoothness;
Second approximation means for linearly approximating the curve shape at the line tip of the figure with a second smoothness;
Has,
The image forming apparatus according to claim 1, wherein the first and second smoothness levels can be individually specified. And a third approximation unit for linearly approximating a curved shape of a connecting portion between the lines of the graphic with a third smoothness that can be specified separately from the first and second smoothness. The image forming apparatus according to claim 1. Furthermore,
Determining means for determining the type of page description language that describes the print data;
Setting means for setting the first and second smoothness according to the determined type of the page description language;
The image forming apparatus according to claim 1, further comprising: Furthermore,
Determining means for determining the type of page description language that describes the print data;
Setting means for setting the first, second, and third smoothness according to the determined type of the page description language;
The image forming apparatus according to claim 2, further comprising: A method for controlling an image forming apparatus that forms an image based on print data described in a page description language,
A first approximation step of linearly approximating a curve portion of a graphic given by a drawing command in the print data with a first smoothness;
A second approximation step of linearly approximating the curved shape of the line tip of the figure with a second smoothness that can be specified separately from the first smoothness;
A method for controlling an image forming apparatus, comprising: A program for controlling an image forming apparatus that forms an image based on print data described in a page description language,
A first approximation step of linearly approximating a curve portion of a graphic given by a drawing command in the print data with a first smoothness;
A second approximation step of linearly approximating the curved shape of the line tip of the figure with a second smoothness that can be specified separately from the first smoothness;
The program to execute.

Images