JP2002002027A - Print processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a print processor in which the circuit scale and cost are reduced by reducing the memory capacity and the throughput of processing is improved by reducing memory access. SOLUTION: A data developing section 4 generates image data of (n) colors simultaneously for each pixel from print data, e.g. intermediate data, and stores them in a buffer section 5 for storing developed data. A point sequential/plane sequential converting section 6 reads out the image data of (n) colors stored as a mass for each pixel in the buffer section 5 and divides them for each color component. A color component forming an image at first at an imaging section 9 is outputted to an image data transfer section 8, and other color components are stored sequentially at corresponding areas of an image data buffer section 7. The image data transfer section 8 receives image data of the color component forming an image at first from the point sequential/plane sequential converting section 6, sequentially reads out image data of other color components stored in the image data buffer section 7, and outputs them synchronously to corresponding imaging sections 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print processing apparatus capable of performing print processing in page units, and more particularly to a print processing apparatus for forming a color image by arranging image forming means for each of a plurality of color components. is there.

[0002]

2. Description of the Related Art In recent years, a color printer adopting a tandem system has been developed which is capable of high-speed printing as compared with a single system in which a single photosensitive member forms an image of a plurality of colors. FIG. 6 is a schematic configuration diagram illustrating an example of a tandem-type printer. In the figure, 51 is a Y image forming unit, 5
Reference numeral 2 denotes an M image forming unit, 53 denotes a C image forming unit, 54 denotes a K image forming unit, 55 denotes a sheet, 56 denotes a transport belt, 57 denotes a sheet tray, 58 denotes a buffer memory, and 59 denotes a data developing unit. In the tandem system, a plurality of image forming units, each of which forms an image of only one color, are provided at predetermined intervals along a paper transport path. In the example shown in FIG.
(Yellow), M (magenta), C (cyan), K
For each color of (black), a Y image forming unit 51, an M image forming unit 52, a C image forming unit 53, and a K image forming unit 54 are provided, and the image forming units are arranged in this order.

[0003] The paper 55 loaded in the paper tray 57
Are transported on the transport belt 56 one by one. The Y image forming unit 51, the M image forming unit 52,
The C image forming unit 53 and the K image forming unit 54 sequentially
Images of each color are formed on the paper 55 in an overlapping manner. Thereafter, the formed image is fixed, and the sheet 55 is discharged. In this way, a full-color image is formed on the sheet 55.

A buffer memory 58 for storing one frame of output image, and a data developing unit 59 for developing print data into image data for each color are provided for the image forming units for each color. ing.

A functional feature of the tandem system is that printing is completed in one pass because images are formed simultaneously and in parallel for each color. On the other hand, the photoconductors provided in the image forming means of each color are sequentially arranged at predetermined intervals with respect to the transport path. Therefore, there is a difference in the transfer start time of each color depending on the interval between the photoconductors of each color, and it is necessary to adjust the time difference.

For example, the Y image forming section 5 is arranged in the order described above.
1. When the M image forming unit 52, the C image forming unit 53, and the K image forming unit 54 are arranged, the transfer of the Y toner image is first performed on the sheet, and then the M,
The transfer of the C and K toner images is sequentially performed. That is,
Even if the transfer of the Y toner image is started in the Y image forming unit 51, at that time, the M image forming unit 52 and the C image forming unit 5
3. In the K image forming unit 54, the transfer of the image is not started. After the transfer of the Y toner image by the Y image forming unit 51 is started, the sheet is conveyed to the M transfer position, and then the transfer of the M toner image by the M image forming unit 52 is started. At this time, the C image forming unit 53 and the K image forming unit 5
In No. 4, image transfer is not started. After the transfer of the M toner image in the M image forming unit 52 is started, the sheet is conveyed to the C transfer position,
Then, the transfer of the K toner image in the K image forming unit 54 is started after the sheet is conveyed to the K transfer position.

As described above, there is a time lag in the transfer start time of the toner image for each photoconductor of each color arranged in parallel. For this purpose, raster image data is converted into Y, M,
For each of the colors C and K, it is necessary to store the data until the start of the transfer. For this purpose, a buffer memory 58 is prepared for each color. By storing the raster image data in the buffer memory 58, it is possible to read out the raster image data from the respective buffer memories 58 in synchronization with the transfer start timing of each color, and form and transfer the toner image.

Further, in order to develop the image data into the buffer memory 58 of each color, a data developing section 59 is provided. FIG. 7 is a configuration diagram illustrating an example of the data expanding unit. In the figure, 61 is a communication unit, 62 is an intermediate data buffer unit, 63 is an intermediate data expansion unit, 64 is an expansion data storage buffer unit, 65 is a dot-sequential plane-sequential conversion unit, and 66 is an image data transfer unit. In the configuration of the data expanding unit 59 shown in FIG. 7, it is assumed that intermediate data stored in an external intermediate data storage unit is input as print data.

[0009] The communication section 61 communicates with the intermediate data storage means. The intermediate data buffer unit 62 stores intermediate data transferred from the communication unit 61. Intermediate data expansion unit 6
Reference numeral 3 reads the intermediate data from the intermediate data buffer unit 62 and simultaneously generates image data of n colors for each pixel.
The expanded data storage buffer unit 64 includes the intermediate data expanding unit 6
The image data for n colors output from 3 for each pixel is stored for each band. The dot-sequential plane-sequential conversion unit 65 outputs image data for n colors read out for each pixel from the expanded data storage buffer unit 64 for each color component.

The image data for each color component output from the dot-sequential plane-sequential conversion unit 65 is stored in the buffer memory 5.
8 is stored. Then, although not shown in FIG. 6, the image data transfer unit 66 reads the image data for each color component from the buffer memory 58 and transfers the image data to the image forming unit corresponding to each color component. At this time, the image data is transferred in consideration of the timing difference as described above.

In such a configuration, the intermediate data developing unit 6
The image data for n colors for each pixel, which are simultaneously generated from No. 3, are transferred to the respective image forming units by being shifted by the above-described transfer start time difference generated in the n image forming units for each color. . In order to absorb the transfer start time difference, it is necessary to hold the image data corresponding to the start of transfer of each image forming unit. For this purpose, the development data storage buffer unit 64, the dot-sequential plane-sequential conversion unit 65, the buffer memory 58, an image data transfer unit 66, and the like.
Of these, the dot-sequential plane-sequential conversion unit 65 and the image data transfer unit 66 have only a control function, so the circuit scale is much smaller than that of the intermediate data expansion unit 63 and the like, and together with the communication unit 61 and the intermediate data expansion unit 63 One chip is possible. However, the expanded data storage buffer unit 64 and the buffer memory 58 may need a capacity of one page,
There is a problem that the circuit scale is increased and the cost is increased. Also, the expanded data storage buffer unit 64,
Since the access to the buffer memory 58 and the like is frequently performed, there is a problem that the bus use efficiency is reduced.

In recent years, in order to reduce the buffer memory for each color under cost reduction, raster image data is generated by band-dividing raster image data in the scanning direction so as to correspond to the distance between image forming units for each color. Data is now handled for each band. As a technical example relating to the handling of data for each band, for example, Japanese Patent Application Laid-Open No. H11-188927
There is a technique described in Japanese Unexamined Patent Publication (Kokai) No. H11-26095.

Japanese Patent Application Laid-Open No. 11-188927 discloses a print processing apparatus that efficiently absorbs a transfer start time lag of a toner image for each image forming unit of each color arranged in parallel by a tandem type color image output unit. I have. According to this print processing apparatus, the intermediate data for one page generated from the print data is written to the intermediate data buffer unit in band units, and the intermediate data expansion unit provided for each color component corresponds to each transfer timing. The intermediate data for each band is read out and expanded, and the image data is transferred to the corresponding image forming unit. Thereby, the image forming units (photoconductors) of each color arranged in parallel
The image formation start time lag for each image can be efficiently absorbed by changing the band of the intermediate data read by each intermediate data developing unit. The expanded data storage buffer unit 64 and the dot-sequential plane-sequential conversion unit 6 as shown in FIG.
5, the buffer memory 58, the image data transfer unit 66, etc. are unnecessary. Further, since the intermediate data buffer means has one page of data, the memory capacity is reduced, and the cost of the memory can be greatly reduced.

However, Japanese Patent Application Laid-Open No. 11-188927
In the print processing apparatus described in Japanese Patent Application Laid-Open Publication No. H10-260, there is a problem that an intermediate data developing unit is provided for each color component, and the circuit scale is increased, which leads to an increase in cost. Further, since it is necessary to read the intermediate data of the same band from the intermediate data buffer means a number of times equal to the number of the n color components, there is a problem that the bus use efficiency is reduced.

In order to reduce the circuit scale, it is conceivable to read out the intermediate data only once by one developing means and to simultaneously generate image data for n colors for each pixel. In this case, FIG. The expanded data storage buffer unit 64
The point-sequential frame-sequential conversion unit 65, the buffer memory 58, the image data transfer unit 66, and the like are required. By performing processing in band units, the expanded data storage buffer 6
4 and the capacity of the buffer memory 58 can be reduced as compared with the case where one page of image data is stored, so that the circuit scale can be reduced and the cost can be reduced. Of course, even if these are provided, the circuit scale can be reduced as compared with the case where the developing means is provided for each color. However, the problem that the bus use efficiency is still low is not solved. Further, there is a demand for further reduction in circuit scale and cost by further reducing the buffer memory.

[0016]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and aims to reduce the memory capacity to reduce the circuit scale and cost, and to reduce the memory access, and It is an object of the present invention to provide a print processing apparatus with improved processing throughput.

[0017]

SUMMARY OF THE INVENTION The present invention provides a tandem system in which an image of individual color components is formed by image forming means arranged side by side from image data in which n color components of print data are individually developed. A print processing apparatus that forms a full-color image by using the data developing means to simultaneously generate n-color image data for each pixel based on the input print data and store the image data in the developed data storage means. The conversion means reads the image data of n colors from the expanded data storage means for each pixel and outputs the data to the output buffer means for each color.
For the image data of the color components that form the image first,
Output directly to the image forming means. As a result, the transfer of image data to the image forming means for forming an image first does not go through the output buffer means, so that the access to the output buffer means is reduced by that much and the bus use efficiency can be improved. Thus, the overall processing throughput can be improved. Further, the output buffer means is not necessary for the color components which form an image first, so that the memory capacity can be reduced by that amount, and the circuit scale and cost can be reduced.

Although the output buffer means is not necessary for the color components which form the image first as described above,
It is not necessary for the other color components to have the same capacity, and it is sufficient if there is a capacity determined for each color based on the distance from the image forming unit that first forms an image to the image forming unit corresponding to each color. By determining the capacity for each color in this manner, the memory capacity can be further reduced. Further, by mapping the expanded data storage means and the output buffer means in the same memory space, the memory capacity can be further reduced.

[0019]

FIG. 1 is a block diagram showing an embodiment of a print processing apparatus according to the present invention. In the figure, 1 is a drawing data input unit, 2 is an intermediate data generation unit, 3 is an intermediate data storage unit, 4 is a data development unit, 5 is a development data storage buffer unit, 6 is a dot-sequential plane-sequential conversion unit, and 7 is an image. A data buffer unit, 8 is an image data output unit, and 9 is an image forming unit.
The print processing apparatus shown in FIG.
A full-color image is formed on a recording medium by a tandem method in which color images are sequentially formed.

The drawing data input unit 1 receives drawing data described by a predetermined drawing command that describes a drawing element such as a character, a figure, or an image. The drawing data input to the drawing data input unit 1 is input to the intermediate data generation unit 2.
The intermediate data generation unit 2 divides a drawing element included in the drawing data for each band area, and converts the data into intermediate data in an intermediate data format. This intermediate data generation unit 2
The intermediate data generated in step (1) is input to the intermediate data storage unit 3 and stored in band units. The intermediate data written in the intermediate data storage unit 3 is read by the data development unit 4 as print data. When print data similar to the intermediate data is input from the beginning, the intermediate data generation unit 2 is unnecessary, the print data is received by the drawing data input unit 1, and the print data is stored in the intermediate data storage unit 3. do it.

The data development unit 4 reads the print data from the intermediate data storage unit 3, simultaneously generates n-color image data for each pixel, and stores the image data in the development data storage buffer unit 5. The expanded data storage buffer unit 5 stores the image data of the four colors expanded by the data expanding unit in the order of pixels in band units. FIG. 2 is an explanatory diagram of an example of the data structure of the image data stored in the expanded data storage buffer unit 5. In this example, four color components of Y, M, C, and K are used as the n color components. Since the image data of the four colors Y, M, C, and K are simultaneously generated for each pixel in the data expansion unit 4, the arrangement of the image data stored in the expansion data storage buffer unit 5 is shown in FIG. Y1, M1, C
1, K1, Y2, M2, C2, K2, ..., Ym, Mm,
Cm and Km. Of course, Y, M, C,
The arrangement of the data of K is not limited to this example. If the expanded data storage buffer unit 5 is configured to have a double buffer configuration in band units, while the dot-sequential plane-sequential conversion unit 6 reads out the expanded image data from one buffer, Thus, the image data developed by the data development unit 4 can be written, and efficient processing can be performed.

The dot-sequential plane-sequential conversion unit 6 reads the n-color image data stored in the development data storage buffer unit 5 as a group for each pixel as shown in FIG.
Separate for each color component. The color components for which an image is first formed in the image forming unit 9 are directly output to the image data output unit 8, and the other color components are stored in areas corresponding to the respective color components in the image data buffer unit 7. I do.

The image data buffer unit 7 stores the image data divided for each color component by the dot-sequential plane-sequential conversion unit 6 in band units for each color component. The image data buffer unit 7 does not have an area for a color component in which an image is formed first, and other color components correspond to the respective colors from the image forming unit that forms the image first. An area for storing image data of a data amount determined for each color is secured based on the distance to the image forming unit. In addition,
The area secured for the color components other than the color components forming the image first is secured for each band when the processing is performed for each band.

FIG. 3 is an explanatory diagram of an example of a buffer area provided for each color component in the image data buffer section 7. As shown in FIG. FIG. 3 shows an example in which Y, M, C, and K are used as n colors and an image is formed in this order. As mentioned above,
In the tandem system, the image forming units of the respective colors are provided at remote positions. Further, as described above, the dot-sequential plane-sequential conversion unit 6 reads out image data of all color components of one pixel at a time. Therefore, for example, assuming that a color component that initially forms an image is Y, the same pixel on which an image is formed by the Y image forming unit is used until an image is formed by the M, C, and K image forming units.
It is necessary to store at least image data of M, C, and K colors.

The amount of data that must be stored is determined by the distance between the Y image forming unit for forming an image first and the M, C, and K image forming units. For example, between the Y image forming unit and the M image forming unit, Y
Are formed, and the corresponding M image data must be stored. Therefore, as shown in FIG. 3A, the image data of the M color corresponding to the distance between the Y image forming unit and the M image forming unit is held in the image data buffer unit 7. Similarly, as shown in FIG. 3B, image data of C color corresponding to the distance between the Y image forming unit and the C image forming unit is held in the image data buffer unit 7 and shown in FIG. Thus, the image data of the K color corresponding to the distance between the Y image forming unit and the K image forming unit may be held in the image data buffer unit 7. As described above, the amount of data that must be stored for each color component is different, and the amount of data depends on the distance from the image forming unit that first forms an image. Therefore, by securing an area of a data amount corresponding to each color component, the memory amount can be reduced as compared with a case where an area of the same size is secured uniformly. Further, for the Y image forming unit for forming an image first, the image data may be transferred without passing through the image data buffer unit 7.
There is no need to reserve an area for the Y color in the image data buffer unit 7. Therefore, the memory amount can be reduced by the amount of the Y color.

When the image data is processed for each band, it is desirable to secure the capacity of the area for each band of M, C, and K in units of bands. It is only necessary to store data equal to or larger than the data amount corresponding to the distance from the image forming unit to be used. In FIG. 3, M1, M2,..., Mm, C1, C2,.
A rectangle including K1, K2,..., Km indicates a unit of one band.

Returning to FIG. 1, the image data output unit 8 receives the image data of the color component from which the image is first formed, which is output from the point-sequential plane-sequential conversion unit 6, and stores the image data in the image data buffer unit 7. The read image data of each of the other color components is sequentially read and output to the image forming unit 9 of the corresponding color component in synchronization with the serial output clock signal.

As described above, for the color components which form an image first, image data is directly transferred from the point-sequential frame-sequential conversion unit 6. One of the possible reasons for this is that the dot-sequential frame-sequential conversion unit is used. The image data output unit 8 can read the image data from the image data buffer unit 7 at the same speed as that at which the image data is written into the image data buffer unit 7. That is, similarly to the case where the image data is read from the image data buffer unit 7, the image data from the dot-sequential plane-sequential conversion unit 6 can also be received. Also, unlike the case where the size of the input intermediate data and the size of the image data output after expansion are different, as in the data expansion unit 4, for example, the input image data and the output image data are different in the image data output unit 8. Since they are completely the same, the bandwidths required for input and output are the same, and image data is read from the image data buffer unit 7 at a speed corresponding to the data transfer speed required by the image forming unit 9, and the image data is You just need to get it. Further, as described with reference to FIG. 3, a buffer memory for absorbing an image forming start time lag with an image forming unit that forms an image first like other color components is always necessary for a color component that forms an image first. Therefore, it is possible to directly transfer the image data from the dot-sequential plane-sequential conversion unit 6 to the image forming unit 9.

In the configuration shown in FIG. 1, for example, the expanded data storage buffer unit 5, the image data buffer unit 7, and the intermediate data storage unit 3 use different memories, and occupy areas in the same memory space. It is possible to arrange them separately.

FIG. 4 is a block diagram showing an example of a print processing system including an embodiment of the print processing apparatus of the present invention. In the figure, 11 is an output asynchronous processing unit, 12 is an output synchronous processing unit, 21 is a document creation unit, 22 is a spool unit, 23 is a lexical interpretation unit, 24 is an intermediate data generation unit, 25
Denotes an intermediate data storage unit, 31 denotes a temporary storage unit, 32 denotes a development processing unit, and 33 denotes an output unit. The print processing system shown in FIG. 4 is roughly divided into two blocks. One is an output asynchronous processing unit 11, and the other is an output synchronous processing unit 12.

The output asynchronous processing section 11 includes a document creating section 21, a spool section 22, a lexical interpretation section 23, an intermediate data generating section 24, an intermediate data storage section 25, and the like, and operates asynchronously with the output synchronous processing section 12. . These may be realized on one computer, but for example, the document creation unit 21 is realized on the client host computer,
Spool unit 22, lexical interpretation unit 23, intermediate data generation unit 2
4 and the intermediate data storage unit 25 may be realized on a server host computer, for example, and the document creation unit 21 and the spool unit 22 may be connected by, for example, a network. The processing in the output asynchronous processing unit 11 is performed asynchronously with the processing in the output synchronous processing unit 12 by storing the processing result in a storage device.

The document creation section 21 creates drawing data described in a predetermined description language from document data generated by an application program for processing document creation and editing in a personal computer, a workstation, or the like. It has a function.
The description language is, for example, GDI (Graphical De)
Vice Interface, trademark of Microsoft Corporation), Acrobat (Adobe Systems)
PDF (Portable Do)
document Format), PostScript
(Page Description Language, such as Adobe Systems Corp.)
age).

The spool section 22 is provided for the document creating section 2
Communication function for inputting the print data generated in step 1,
Alternatively, it has a function of temporarily storing drawing data until it is output to the lexical interpretation unit 23.

The lexical interpretation unit 23 cuts out the drawing data input from the spool unit 22 as a token in accordance with the syntax of a predetermined description language, and outputs the token to the intermediate data generation unit 24.

The intermediate data generation unit 24 includes a lexical interpretation unit 23
Receives and interprets the token output from the CPU, executes the rendering command, generates intermediate data in the form of a trapezoid as a basic unit for each rendering command, and stores the intermediate data in the intermediate data storage unit 25 or the temporary storage unit 31 of the output synchronization processing unit 12. send. The purpose of generating the intermediate data is to enable high-speed expansion processing synchronized with the output unit 33 in the expansion processing unit 32,
This is to ensure that the development processing time in is completed within a predetermined time. For this reason, the intermediate data is simplified so that the drawing time can be predicted.

The intermediate data storage unit 25 stores the intermediate data input from the intermediate data generation unit 24 in a predetermined unit such as each band or each page.
The intermediate data is sent out by a predetermined unit in response to a request from.

The output synchronization processing unit 12 includes a temporary storage unit 31,
It includes a development processing unit 32, an output unit 33, and the like, and performs processing in synchronization with the output unit 33. The output synchronization processing unit 12 can be configured by, for example, a dedicated hardware processing device.

The temporary storage unit 31 stores the intermediate data storage unit 25
Is a buffer for temporarily storing a part of the intermediate data stored in the buffer. The expansion processing unit 32 includes a temporary storage unit 31
The intermediate data temporarily stored in the
In synchronization with the output process, the intermediate data is developed into image data of a bitmap format or the like that can be directly printed by the output unit 33 and output. The output unit 33 receives the image data output from the development processing unit 32, forms an image on a recording sheet, and outputs the image. For example, a color image forming engine using an electrophotographic system of a laser scanning system capable of performing exposure, development, and transfer in parallel for each of Y, M, C, and K colors and outputting a full-color image may be used.

As above, an example of the print processing system has been described. In such a print processing system, when printing an image, after the drawing data is generated in the output asynchronous processing unit 11, it is converted into intermediate data by the intermediate data generation unit 24 and stored in the intermediate data storage unit 25. You.
Thereafter, the output synchronization processing unit 12 synchronizes with the output unit 33,
The intermediate data is expanded into bitmap data or the like by the expansion processing unit 32, and an image is printed by the output unit 33.

FIG. 5 is a block diagram showing an example of the output synchronization processing section 12 in an example of a print processing system including an embodiment of the print processing apparatus of the present invention. In the figure, the same parts as those in FIG. 41
, A communication unit; 42, an intermediate data buffer unit; and 43, a bus.

The temporary storage unit 31 includes a communication unit 41 and an intermediate data buffer unit 42. The expansion processing unit 32 includes a data expansion unit 4, an expansion data storage buffer unit 5, a dot-sequential plane-sequential conversion unit 6, an image data buffer unit 7, and an image data transfer unit 8. The output of 8 is connected to an output section 33 which is a tandem type color output device. These sections of the temporary storage section 31 and the expansion processing section 32 are interconnected by a bus 43.

In the temporary storage section 31, the communication section 41 communicates with the intermediate data generation section 24 or the intermediate data storage section 25, and stores the intermediate data in the intermediate data buffer section 42. The intermediate data buffer unit 42 includes a buffer memory that temporarily stores intermediate data developed by the development processing unit 32.

In the expansion processing section 32, the data expansion section 4, expanded data storage buffer section 5, dot-sequential plane-sequential conversion section 6, image data buffer section 7, and image data transfer section 8
These are described in FIG. In brief, when the colors to be used are Y, M, C, and K, the data expanding unit 4 reads the intermediate data to be expanded from the intermediate data buffer unit 42, and reads the image data of each of the colors Y, M, C, and K. Are simultaneously generated for each pixel, and the expanded data storage buffer 5
To be stored. The expanded data storage buffer unit 5 includes a buffer memory that stores image data of all colors expanded by the data expanding unit 4 in band units. The structure of the stored image data is, for example, as described with reference to FIG. The point-sequential plane-sequential conversion unit 6 reads out the Y, M, C, and K image data stored in a lump for each pixel in the development data storage buffer unit 5 and divides it for each color component. The Y color component on which the image is formed is output to the image data transfer unit 8, and the other color components are separately stored in regions corresponding to the respective color components of the image data buffer unit 7 and sequentially stored. The image data buffer unit 7 is a memory buffer that stores the image data divided for each color component by the dot-sequential plane-sequential conversion unit 6 in band units for each color component. As described above, the number of bands is determined based on the number of bands corresponding to the distance from the image forming unit that first forms an image in the output unit 33 to the image forming unit for the color component. Note that an area for the Y color in which an image is first formed in the output unit 33 is not secured. Image data transfer unit 8
Receives the image data of the Y color component output from the dot-sequential plane-sequential conversion unit 6 and sequentially reads out the image data of the other color components stored in the image data buffer unit 7,
The output unit 33 outputs the color component to the image forming unit of the corresponding color component in synchronization with the serial output clock signal.

With such a configuration, the capacity of the image data buffer unit 7 can be reduced as described above, and the circuit scale and cost can be reduced. Further, as shown in FIG. 4, in a configuration in which each unit of the expansion processing unit 32 and each unit of the temporary storage unit 31 are connected by the bus 43, the intermediate data buffer unit 42, the expansion data storage buffer unit 5, the image data buffer unit The bus 43 is used by accessing the bus 7. For this reason, the bandwidth of the bus 43 may be a bottleneck and the speed of the apparatus may be suppressed. As described above, in the configuration using the print processing apparatus of the present invention, the writing and reading of the image data buffer unit 7 are not performed for the color components that form an image first, so that the memory access is reduced accordingly. The bandwidth allocated to each of the other processing units can be increased. Therefore, for example, even when developing intermediate data having a larger data amount, the data expanding unit 4 can perform the expanding process without waiting for reading of the intermediate data from the intermediate data buffer unit 42.
Thus, the overall processing throughput can be improved by alleviating the bottleneck of the bus 43.

In the above description, four colors of Y, M, C, and K are used as specific examples, and the Y color is used as a color for first forming an image. However, the present invention is not limited to this. Instead, the present invention can be applied to an apparatus that uses arbitrary n colors and uses an arbitrary color as a color for forming an image first.

[0046]

As is apparent from the above description, according to the present invention, when a plurality of image forming means are juxtaposed to form a color image, the n-color image developed by the data developing means in pixel order. Of the data, the image data of the color component on which an image is first formed is divided for each color component by the conversion means and then directly transferred to the image forming means. by this,
An output buffer dedicated to a color component in which an image is formed first becomes unnecessary, and the memory access is reduced and the bus use efficiency is increased, thereby improving the data transfer rate of the bus and improving the throughput of the entire expansion processing. The effect is that it becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of a print processing apparatus according to the present invention.

FIG. 2 is an explanatory diagram of an example of a data structure of image data stored in a developed data storage buffer unit 5;

FIG. 3 is an explanatory diagram of an example of a buffer area provided for each color component in an image data buffer unit 7;

FIG. 4 is a block diagram illustrating an example of a print processing system including an embodiment of the print processing apparatus of the present invention.

FIG. 5 is a block diagram illustrating an example of an output synchronization processing unit in an example of a print processing system including an embodiment of the print processing apparatus of the present invention.

FIG. 6 is a schematic configuration diagram illustrating an example of a tandem-type printer.

FIG. 7 is a configuration diagram illustrating an example of a data development unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Drawing data input part, 2 ... Intermediate data generation part, 3 ... Intermediate data storage part, 4 ... Data development part, 5 ... Development data storage buffer part, 6 ... Point-sequential plane sequential conversion part, 7 ... Image data buffer part .. 8 image data output unit 9 image forming unit 11 output asynchronous processing unit 12 output synchronous processing unit
21: document creation unit, 22: spool unit, 23 ...
Lexical interpretation unit, 24 intermediate data generation unit, 25 intermediate data storage unit, 31 temporary storage unit, 32 expansion processing unit, 33
... Output unit, 41 communication unit, 42 intermediate data buffer unit, 43 bus, 51 Y image forming unit, 52 M image forming unit, 53 C image forming unit, 54 K image forming unit, 55
... paper, 56 ... transport belt, 57 ... paper tray, 58 ...
Buffer memory, 59: data development unit, 61: communication unit,
Reference numeral 62 denotes an intermediate data buffer unit, 63 denotes an intermediate data expansion unit, 64 denotes an expansion data storage buffer unit, 65 denotes a dot-sequential plane-sequential conversion unit, 66 denotes an image data transfer unit.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C087 AA15 BA03 BA07 BC02 BC05 BD34 BD35 5B021 AA02 BB04 CC02 CC05 DD16 DD20 5C073 BB02 CA02 CC01 5C079 HB03 KA01 MA02 NA10 NA11 NA25 PA07

Claims (5)

[Claims] A print processing apparatus for forming a color image by forming an image of each color component from image data in which n color components of print data are individually developed by image forming means arranged side by side. , Data development means for simultaneously generating n-color image data for each pixel based on input print data, and development data for storing the n-color image data developed by said data development means in pixel order in band units Storage means, conversion means for reading out the n-color image data for each pixel from the development data storage means and outputting for each color, and storing the image data for each color output from the conversion means in an area for each color Output buffer means, and output means for outputting image data for each color component from the output buffer means to the image forming means, wherein the conversion means Wherein the image data of a color component forming an image is output directly to the image forming means, and the other color components are output to the output buffer means. 2. An intermediate data generating means for converting input drawing data into intermediate data in an intermediate data format, and an input for storing the intermediate data generated by the intermediate data generating means for each predetermined unit. 2. The print processing apparatus according to claim 1, further comprising a buffer unit, and passing the intermediate data stored in the input buffer unit to the data expanding unit as the print data. 3. The output buffer means for each color stores image data of a data amount determined for each color based on a distance from an image forming means for first forming an image to an image forming means corresponding to each color. The print processing apparatus according to claim 1, wherein the print processing apparatus stores the print data. 4. The print processing apparatus according to claim 1, wherein at least the expanded data storage unit and the output buffer unit are mapped in a same memory space. 5. The expansion data storage means has a double buffer configuration in band units.
The print processing device according to claim 4.