JPH09167243A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the plotting processing time by using repetitively a plotting work memory to process every divided plotting area and to process these areas in parallel to each other and also to reduce the memory cost and to decrease the number of plotting objects by forming a graphic that is held between both monotonous increase or decrease curves at the right and left when the plotting areas are divided. SOLUTION: This device consists of an inverpreter part 1 which converts a page description language into a plotting object, a plotting object storage part 2, a band division part 3 which divides a plotting area into plural bands, a rasterization part 4 which converts the plotting object into the rasterization data, a rasterization data storage part 5 which stores the rasterization data, and a plotting output part 6 which outputs the stored rasterization data to a plotting screen. A switching control part 7 is added to successively store the rasterization data on the following divided bands in the part 5 when the rasterization data stored in the part 5 are outputted by the part 6 and then outputs the rasterization data via the part 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an electrophotographic copying machine, a printer and a fax machine, and more particularly to a drawing operation of a page description language of the image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus which performs a drawing operation by changing a page description language into a drawing object has a print area as a memory for storing rasterized data necessary for the drawing operation according to a print paper size and a resolution. It requires a memory capacity that can represent the entire image, so depending on the print area, resolution, number of gradations, color tone, etc.,
A large amount of memory was needed. In addition, since the drawing area of the drawing object was divided into trapezoids when dividing, the drawing area surrounded by curved lines is divided into many drawing objects and requires a large amount of memory space. However, there is a problem that the processing becomes complicated and the processing time becomes long.

[0003]

As described above, the conventional image forming apparatus requires a large-capacity memory for storing the rasterized data required for drawing work, and further the drawing area is divided. Since the object is divided into trapezoids, a large amount of memory is required for storage, and the processing becomes complicated and the processing time becomes long. Therefore, an object of the present invention is to execute a drawing operation sequentially for each band into which a drawing area is divided, and to repeatedly use one or a plurality of memories that it possesses to process the divided bands, thereby reducing the memory capacity. It is an object of the present invention to provide an image forming apparatus that can reduce the cost and reduce the drawing processing time by processing the drawing work of a plurality of bands in parallel. In addition, when dividing the drawing area of a drawing object, the left and right sides are made into a figure that is sandwiched by curves of monotonically increasing or decreasing, the number of drawing objects is reduced, and the memory capacity to be stored is also reduced. An object of the present invention is to provide an image forming apparatus that shortens the processing time.

[0004]

In order to achieve this object, the invention according to claim 1 of the image forming apparatus according to the present invention is an interpreter unit for converting a page description language for drawing work into a drawing object, and a drawing object. A drawing object storage unit that stores the drawing object, a band division unit that divides the drawing area of the drawing object stored in the drawing object storage unit into a plurality of bands, and the bands divided into the band division unit are sequentially drawn. A rasterizing unit that converts an object into rasterized data, a rasterized data storage unit that stores rasterized data,
The rasterizing data stored in the rasterized data storage unit is output to the drawing surface, and the drawing output unit outputs the rasterized data in the rasterized data storage unit, thereby sequentially dividing the rasterized data. The most main feature is that the rasterization data of the band is stored in the rasterization data storage unit, and a switching control unit for outputting the data by the drawing output unit is provided.

The invention according to claim 2 of the image forming apparatus according to the present invention is the image forming apparatus according to claim 1,
The rasterizing section and the rasterizing data storage section are the main features of being an image forming apparatus having a plurality of them. The invention according to claim 3 of the image forming apparatus according to the present invention is, in the image forming apparatus according to claim 2, characterized in that the switching control section is an image forming apparatus which processes the divided bands in parallel. Characterize. The invention according to claim 4 of the image forming apparatus according to the present invention,
Alternatively, in the image forming apparatus described in 3, the band dividing unit is mainly an image forming apparatus that divides into drawing objects for each figure sandwiched by a horizontal line at the top and bottom and a monotonically increasing or decreasing curve at the left and right. It is a characteristic.

[0006]

According to the image forming apparatus of the present invention, when the rasterizing data is output to the drawing surface by the drawing output unit, the switching control unit can process the next band. Therefore, the rasterizing unit and the rasterizing data can be processed. It suffices if the storage unit corresponds to at least one divided band for drawing the entire image. Claim 2
Since the image forming apparatus described above has a plurality of rasterizing units and rasterizing data storage units, even if a part fails, it can be replaced and used, and the data in the rasterizing data storage unit can be output to the drawing surface. The rasterizing process of the next divided band can be performed even while the band is in progress. In the image forming apparatus according to the third aspect of the present invention, since the switching control unit can process the divided bands in parallel, the switching control unit associates the plural divided rasterizing units with one another. ,
Rasterization processing can be performed in parallel, and the created rasterized data can be stored in the corresponding rasterized data storage unit. In the image forming apparatus according to the fourth aspect, the band dividing unit is divided into drawing objects for each figure sandwiched by a horizontal line at the top and bottom and a monotonically increasing or decreasing curve at the left and right. Unlike the trapezoidal division, the divided drawing objects are not small, the memory to store is small, and the number of rasterization processes is small.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 is a block diagram of a main part of an image forming apparatus according to an embodiment of the present invention, in which 20 is an image forming apparatus and 21 is an external apparatus. The image forming apparatus 20 is an interpreter section 1 and a drawing object storage section. 2, a band division unit 3, a rasterization unit 4, a rasterization data storage unit 5, a drawing output unit 6, a switching control unit 7, a display / operation unit 8, a storage unit 9, a transmission / reception unit 10, and a control unit 11. The page description language related to drawing work is sent from the external device 21 such as a personal computer to the image forming apparatus 20 through the transmission line, and the image forming apparatus 20 side receives it via the transmission / reception unit 10 connected to the transmission line and stores it in the storage unit. It is temporarily stored in the portion used as the data memory of 9. In the interpreter unit 1, the page description language relating to the drawing work stored in the storage unit 9 is stored in the image forming apparatus 20.
The drawing objects are stored in the drawing object storage unit 2 instead of the drawing objects so that the drawing objects can be easily drawn.

The band dividing unit 3 divides the drawing area of the drawing object stored in the drawing object storage unit 2 into a plurality of bands, restores the divided drawing object for each band, and stores it again in the drawing object storage unit 2. . Further, when one drawing object is shared by the divided upper and lower bands, the divided area is slightly shifted to set the band so that there is no shared drawing object. The drawing objects in the drawing area divided into bands are converted by the rasterizing unit 4 into rasterized data in a format that can be drawn by the drawing output unit 6 for each band, stored in the rasterized data storage unit 5, and stored in the rasterized data storage unit 5. The rendered rasterized data is rendered by the rendering output unit 6. What is drawn and output here may be something like a display of the display / operation unit 8 or may be on paper (not shown). When the drawing operation of the first band is completed, the switching control unit 7 causes the rasterizing unit 4 to convert the drawing object of the next band into rasterized data. Also, the data converted to rasterized data is
It is stored in the rasterized data storage unit 5, and the drawing output unit 6
To draw after the first band. In this way, the switching operation of the switching control unit 7 is repeated, and the drawing work for all bands is performed to complete the entire image. The control unit 11 includes a micro CPU, and controls each component block so that signals can be delivered at a predetermined timing. When the signals cannot be delivered normally, an error state is set to stop the device, and the display / operation unit 8 is operated. Display the error status on the display. Further, the control unit 1 is provided in a part of the storage unit 9.
The program of the 1 micro CPU is stored.

FIG. 2 is an explanatory view showing a state in which a drawing operation is performed by one rasterizing unit 4 and one rasterizing data storage unit 5. The description will be made with reference to the configuration shown in FIG. The drawing object stored in the drawing object storage unit 2 by the band dividing unit 3 is divided into a plurality of bands 2a, 2b, ...
The drawing area is divided into g. The switching control unit 7
The rasterization unit 4 and the rasterization data storage unit 5 are made to correspond to the band area 2a first. Therefore, the drawing object in the band area 2a is converted into rasterized data by the rasterizing unit 4 and stored in the rasterized data storage unit 5. The data stored in the rasterized data storage unit 5 is output by the drawing output unit 6 on the display unit of the display / operation unit 8 or on paper. further,
The rasterization unit 4 and the rasterized data storage unit 5 are controlled by the switching control unit 7 so as to process the band area 2b divided next to the band area 2a. The rasterizing section and the rasterizing data storage section corresponding to the band area 2b are illustrated by the dashed lines 4'and 5'shown below the rasterizing section 4 and the rasterization data storage section 5 shown by the solid lines corresponding to the band area 2a. . Band area 2
The rasterized data of b is stored in the rasterized data storage unit 5
′, And is output by the drawing output unit 6 following the drawing of the band area 2a. By repeating such work, A stored in the drawing object storage unit 2
Is correctly output on the display unit of the display / operation unit 8 or on the paper.

FIG. 3 is a diagram showing a case in which a plurality of rasterizing units 4 and a plurality of rasterizing data storage units 5 are held. In this embodiment, three rasterizing units 4a to 4c and rasterizing data are used. Storage units 5a-5
Description will be made using an example configured in c. Switching control unit 7
The rasterizing unit 4a and the rasterized data storage unit 5a are associated with each other so that the band area 2a is processed by
The rasterizing unit 4b and the rasterized data storage unit 5b are associated with the processing of the band area 2b, and the rasterizing unit 4c and the rasterized data storage unit 5c are associated with the processing of the band area 2c. That is, band 2
The raster area 4a converts the area a into the band area 2b.
The rasterizing section 4b simultaneously converts the band area 2c into rasterized data by the rasterizing section 4c and stores the band area 2c in the rasterized data storage section 5 corresponding to each of the created order. The drawing output unit 6 draws and outputs the rasterized data storage unit 5 from the top in the order of 5a, 5b, and 5c, and outputs it on the display unit of the display / operation unit 8 or on paper. After that, the switching control unit 7 sets 4a, 4
b, 4c three rasterizing sections 4 and 5a, 5b, 5
The three rasterized data storage units 5 of c are set to the band regions 2d, 2e,
Corresponding to 2f, rasterizing processing is performed by each rasterizing unit 4 and rasterizing data is stored by each rasterizing data storage unit 5, which is the same as the series of operations described above. However, unlike the operation shown in FIG. 2, the rasterizing process, which takes time, is performed in parallel, which is a big difference in that the entire processing time can be shortened.

Further, in the above description of the rasterizing process, the rasterizing process is performed on the next set of band areas after all the data in the three rasterizing data storage units 5 are rendered and output. It is also possible to control the rasterized processing from the processed one, and to process at a higher speed. Furthermore, it is possible to further increase the processing speed by providing three or more rasterizing units 4 and the rasterizing data storage unit 5. It should be noted that the three rasterization units 4a, 4b, 4c and the three rasterization data storage units 5a, 5b, 5c are not used for the rasterization processing, but the rasterization unit 4c and the rasterization data storage unit 5c are used for maintenance, for example. You can also Therefore, even if any one of the rasterizing units 4a and 4b and the rasterizing data storage units 5a and 5b being used fails, the rasterizing unit 4c and the rasterization data storage unit 5c assigned for maintenance are immediately replaced to downtime. Can be eliminated.

Next, the drawing area division of the drawing object will be described. First, before describing the image area division in the image forming apparatus according to the present invention, the conventional drawing object division will be briefly described. FIG. 4A is a diagram showing a conventionally used method of dividing a drawing area of a drawing object into trapezoids. In order to divide the drawing object by the trapezoidal division in the drawing area surrounded by the curve a on the left side and the curve b on the right side, it is necessary to divide the curves a and b within a range in which they can be linearly approximated. Therefore, a curved portion having a large unevenness or a curved portion having a small curvature has a tendency to be divided into fine regions. Each divided trapezoidal drawing object is converted into rasterized data.

On the other hand, the drawing area division of the drawing object in the image forming apparatus according to the present invention is shown in FIG.
As shown in FIG. 4, curves similar to those in FIG.
The figure is divided into drawing objects for each figure sandwiched by a curve that increases or decreases monotonically. That is, it is divided at a point at which the curve greatly changes, a point at which the curve changes from an increase to a decrease, or a point at which the curve reversely changes to an increase. It is easy for a current image forming apparatus to create and draw a drawing object that draws a monotonically increasing or monotonously decreasing curve. Also,
As can be seen by comparing the divisions of the drawing objects in FIGS. 4A and 4B, FIG. 4B is an extremely small collection of drawing objects. Therefore, when the drawing area of the drawing object storage unit 2 is divided into a plurality of bands, the divided drawing objects for each band are converted and stored again in the drawing object storage unit 2,
The memory capacity of FIG. 4B is smaller than that of the division method shown in FIG. In FIG. 1, the drawing object storage unit 2 and the rasterized data storage unit 5 have been treated as completely different from each other with a fixed memory capacity, but in reality, they are composed of the same type of storage unit such as a RAM or a hard disk. Further, the two storage units do not constitute a fixed memory capacity, and if a small memory capacity is sufficient, the surplus memory can be utilized as a memory for other necessary work. Furthermore, if the number of drawing objects is reduced, the process of performing drawing work according to the drawing objects becomes simple. In this way, the memory capacity required for drawing work can be reduced, and the processing time required for drawing work can be shortened.

[0014]

As described above, according to the first aspect of the invention, when the rasterization data in the rasterization data storage unit is output to the drawing surface by the drawing output unit, the switching control unit divides the rasterization data storage unit. Since the rasterized data of the next band was stored and the subsequent data could be sequentially output to the drawing surface by the drawing output unit, the memory capacity was very small,
The effect is that an inexpensive image forming apparatus can be provided.

According to the second aspect of the present invention, when a part of the rasterizing unit and the rasterized data storage unit fails, it can be replaced with another rasterized unit and the rasterized data storage unit, and the rasterized data storage unit can be used. Since it is now possible to perform the rasterization processing of the next divided band even while the rasterization data of one part is being output to the drawing surface, it is said that high-speed processing with high reliability is possible. Have an effect.

According to the third aspect of the present invention, the switching control unit switches the plurality of rasterizing units to switch the divided bands one after another so that the rasterizing process is performed in parallel, and the rasterizing data storage units store the rasterized data. As a result, it is possible to provide an image forming apparatus capable of reducing the processing time of the time-consuming rasterization processing and enabling high-speed processing.

According to the fourth aspect of the present invention, the band dividing unit can divide into drawing objects for each figure which are sandwiched by horizontal lines on the upper and lower sides and are horizontally sandwiched by curves of monotonically increasing or monotonically decreasing. , The memory to store is also simplified, the number of rasterization processes is reduced,
This has the effect of reducing the memory cost and providing an image forming apparatus capable of high-speed processing.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a drawing operation of a drawing area divided by the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is another explanatory diagram illustrating the drawing work of the drawing area divided by the image forming apparatus according to the embodiment of the present invention.

4A is an explanatory view for explaining a method of dividing a drawing object in a drawing area by a trapezoidal division, and FIG. 4B is a drawing object divided in a drawing area with a monotonically increasing or monotonically decreasing curve. It is explanatory drawing explaining the method performed for every figure.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Interpreter part, 2 ... Drawing object storage part, 3 ... Band division part, 4 ... Rasterization part, 5 ... Rasterization data storage part, 6 ... Drawing output part, 7 ... ..Switching control unit, 8 ... Display / operation unit, 9 ... Storage unit, 10 ... Transmission / reception unit, 11 ...
Control unit, 20 ... Image forming device, 21 ... External device.

Claims (4)

[Claims] 1. An interpreter unit for converting a page description language related to drawing work into a drawing object, a drawing object storage unit for storing the drawing object, and a drawing object drawing area stored in the drawing object storage unit for a plurality of bands. A band division unit for dividing, a rasterization unit for sequentially converting a drawing object into rasterized data for each band divided by the band division unit, a rasterized data storage unit for storing rasterized data, and a rasterized data storage unit. The rasterization data stored in the rasterization data storage unit is output by the rendering output unit that outputs the stored rasterization data to the rendering surface. In rasterized data storage An image forming apparatus, comprising: a switching control unit for storing and outputting by the drawing output unit. 2. The image forming apparatus according to claim 1, wherein
An image forming apparatus comprising a plurality of the rasterizing units and the rasterizing data storage unit. 3. The image forming apparatus according to claim 2,
The image forming apparatus, wherein the switching control unit processes the divided bands in parallel. 4. The image forming apparatus according to claim 1, claim 2, or claim 3, wherein the band division part is sandwiched by a horizontal line at the top and bottom and a monotonically increasing or decreasing curve at the left and right. An image forming apparatus, wherein the image forming apparatus divides each drawing object.