JPH09131924A - Printing controller, printing control method and color printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of the image quality of an output image which is caused by the execution of a degrading process. SOLUTION: In a printer controller 14, if a banding process is not possible, degrade rendering is carried out (step 307 in illustration 3). In this degrade rendering, full bit map memory having a capacity obtainable from a page buffer 9 is obtained, rendering is executed by maintaining the resolution of color multivalued information included in print data and, at the same time, by decreasing the gradient of the bit data of the color multivalued information, and the result of the process is written into full bit map memory. In order to obtain the full bit map memory having the capacity obtainable from the page buffer 9, the number of gradations of bit data is selected from existing memory capacity so that the output bit gradation of a full bit map is as highest as possible (step 402 and 403).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention analyzes information including color multi-valued information of a page description language system for each page,
The present invention relates to a print control device for generating image data to be supplied to a color printing device by the analysis, a method thereof, and a color printing device.

[0002]

2. Description of the Related Art In recent years, with the advent of high-performance workstations and personal computers, an environment has been provided in which color (full-color) characters, figures, and image data can be easily handled. As a result, the use of color information has been promoted in a wide range of fields such as documents using color information, OHP, slides, arts, and designs.

With the widespread use of such color information, color printing apparatuses for forming and outputting the created color information on paper have been realized and have appeared.

As such a color printing apparatus, there is a page printer which analyzes information including color multi-valued information in a page description language system in page units and prints out in page units. This page printer is currently polarized into a low-priced printer represented by an ink jet system and a thermal transfer type, and a high-priced printer represented by a color laser beam printer.

The above-mentioned low-priced printer has a page memory as in the black-and-white printer, and this page memory is provided with a 1-bit storage area for each color of YMCK.

On the other hand, in the above high-priced printer,
In order to express a plurality of gradations / density (for example, 256 gradations for each color) for each pixel (pixel) unit, the designated color is temporarily stored in a page memory that functions as a page buffer, A print control device is used which controls to send the colors held in the page memory to the printer engine.

However, since it is necessary to store multi-valued YMCK color information in the page memory of this print control device, if the resolution is 300 dpi, the gradation is 8 bits for each color, and the maximum printable paper is A4 size paper, the page As a memory, a capacity of 1M × 4 (color) × 8 (bit) = 32M is required.

Therefore, a high-priced printer such as the laser beam printer can print out a high-detailed image, but the print control device is very expensive, and this print control device is used. The price of the on-board color printing device far exceeds the price of the low-priced printer described above.

In order to keep the price low, analysis of information including color multi-valued information of a predetermined page description language system input from a host computer, creation of halftone image information based on the analysis result, and halftone image thereof are analyzed. Used by a print control device that executes a banding process that performs an operation of writing a processing result in a page memory in parallel with a writing result of a rendering process for information as an image data to be supplied to a printing device in parallel. Has been.

Specifically, in this print control apparatus, the banding process is performed without using the full multi-valued bit map memory, and the color image is developed at a high speed to reduce the memory usage. There is.

However, when the amount of input information from the host computer is too large to realize the image expansion in real time or when the printing by the hard accelerator is impossible, the banding processing means cannot be executed. A method has been proposed and realized that is determined and is controlled so as to execute a degradation process in place of the rendering process in the banding process.

In this degrading process, a bitmap memory having a capacity obtainable from the page memory is acquired, the rendering process is performed on the intermediate information in a state where the resolution is lowered while maintaining the color gradation, and the rendering process is performed. Is written in the bit map memory acquired in the page memory, and the result of the rendering process held in the bit map memory is used as image data for the output image of the color printing apparatus.

[0013]

However, in the above-described degradation processing, the rendering processing is performed on the intermediate information in a state in which the resolution is lowered while maintaining the color gradation, and therefore, it is obtained by performing the degradation processing. The quality of the output image significantly deteriorates as compared with the output image obtained by performing the banding process.

An object of the present invention is to provide a print control device, a print control method, and a color printing device that can suppress deterioration of the image quality of an output image due to a degradation process.

[0015]

According to the first aspect of the present invention,
Analysis of input information including color multi-valued information of a predetermined page description language method, creation of halftone image information based on the analysis result, and writing operation result of the halftone image information to the storage means by rendering processing And banding processing means for performing an operation of reading the processing result held in the storage means in parallel as image data to be supplied to a printing device, and information including the input multi-level color information of a predetermined page description language method. On the other hand, when it is determined that the banding process can be executed and the banding process can be executed,
Color information specified by the information including the input multi-valued color information of a predetermined page description language method, and resolution and color gradation based on preset processing capability are executed on the intermediate information. And a compensating unit that controls to execute a degrading process when it is determined that the banding processing unit cannot be executed, and the degrading process is a bit of a capacity that can be acquired from the storage unit. A bitmap memory obtained by acquiring a map memory, executing a rendering process with the resolution and color gradation corresponding to the obtained capacity of the bitmap memory on the intermediate information, and obtaining a result of the rendering process in the storage means. The result of the rendering process held in the bitmap memory is supplied to the printing device. In the print control apparatus that uses the image data as the image data, the level of the bit data of the color multi-valued information is maintained while maintaining the resolution of the color multi-valued information included in the input information of the predetermined page description language method during the degradation processing. It is characterized in that the result of the rendering process for the intermediate information is written in the bitmap memory with the tonality lowered.

According to a second aspect of the present invention, in the print control apparatus according to the first aspect, the determination means specifies color information designated by the input information including color multivalued information of a predetermined page description language system, The possibility of executing the banding means is determined based on at least one of the time required for the rendering processing with the resolution and the color gradation based on the preset processing capacity and the capacity of the storage means for the intermediate information. To do.

According to a third aspect of the present invention, in the print control apparatus according to the first aspect, a dither process is used as a process for compensating for a decrease in gradation of the bit data of the color multi-valued information. .

According to a fourth aspect of the present invention, analysis of input information including color multi-valued information of a predetermined page description language system, creation of halftone image information based on the analysis result, and rendering to the halftone image information. Banding processing means for executing an operation of reading the processing result held in the storage means as image data to be supplied to the printing device in parallel with the operation of writing the processing result in the storage means by the processing, and the input predetermined page. Judgment means for judging whether or not the banding processing can be executed for the information including the color multi-valued information of the description language method, and the input predetermined page description when it is judged that the banding processing means can be executed. Color information specified by information including language multi-valued color information, resolution and color gradation based on preset processing capability And a compensating unit that controls to execute a degrading process when it is determined that the banding processing unit cannot execute the rendering process. The process acquires a bitmap memory having a capacity that can be acquired from the storage means, executes a rendering process with the resolution and color gradation corresponding to the acquired capacity of the bitmap memory on the intermediate information, and performs the rendering process. In the print control method, the result of is written in the bitmap memory acquired in the storage unit, and the result of the rendering processing held in the bitmap memory is image data to be supplied to the printing device, at the time of the degradation processing, The number of colors included in the input information of the predetermined page description language system Reducing the gradation of the bit data of the color multivalued information while maintaining the resolution of the information and writes the result of the rendering process on the intermediate information to the bit map memory.

According to a fifth aspect of the present invention, in the print control method according to the fourth aspect, the determining means specifies color information designated by the input information including color multi-valued information of a predetermined page description language system, The possibility of executing the banding means is determined based on at least one of the time required for the rendering processing with the resolution and the color gradation based on the preset processing capacity and the capacity of the storage means for the intermediate information. To do.

According to a sixth aspect of the present invention, in the print control method according to the fourth aspect, a dither process is used as a process for compensating for a decrease in gradation of the bit data of the color multi-valued information. .

According to a seventh aspect of the present invention, the input information including the multi-valued color information of a predetermined page description language is analyzed, halftone image information is created based on the analysis result, and rendering is performed on the halftone image information. Banding processing means for executing an operation of reading the processing result held in the storage means as image data for forming an output image in parallel with the operation of writing the processing result in the storage means by the processing; Determining means for determining whether or not the banding processing can be performed on the information including the color multi-valued information of the page description language method, and when it is determined that the banding processing means can be executed, the predetermined input Color information specified by information including page description language color multi-valued information, resolution and color based on preset processing capability And a compensating unit that controls to execute a degrading process when it is determined that the banding processing unit cannot be executed. The degrading process acquires a bitmap memory having a capacity that can be acquired from the storage unit, executes a rendering process with the resolution and color gradation corresponding to the acquired capacity of the bitmap memory on the intermediate information,
In a color printing device that writes the result of the rendering process to the bitmap memory acquired in the storage unit and uses the result of the rendering process held in the bitmap memory as the image data, during the degradation process, the input The result of the rendering process for the intermediate information is reduced by reducing the gradation of the bit data of the color multivalued information while maintaining the resolution of the color multivalued information included in the information of the predetermined page description language method. It is characterized by writing in the memory.

According to an eighth aspect of the present invention, in the color printing apparatus according to the seventh aspect, the determining means specifies color information designated by the input information including color multi-valued information of a predetermined page description language system, The possibility of executing the banding means is determined based on at least one of the time required for the rendering processing with the resolution and the color gradation based on the preset processing capacity and the capacity of the storage means for the intermediate information. To do.

According to a ninth aspect of the present invention, in the color printing apparatus according to the seventh aspect, a dither process is used as a process for compensating for a decrease in gradation of the bit data of the color multi-valued information. .

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the arrangement of a color printing apparatus equipped with an embodiment of the printing control apparatus of the present invention.

As shown in FIG. 1, the color printing apparatus inputs information (hereinafter referred to as print data) including color multivalued information of a predetermined page description language system from a host computer 1 and analyzes the print data. And a printer engine (hereinafter referred to as a printer) 13 that prints an image indicated by the video signal generated by the print control device 14 on a sheet. The host computer 1 creates color information by an application program, converts the color information into print data of a predetermined page description language system, and sends the print data to the print control device 14. This print data includes multi-valued color information.

The print controller 14 is an input buffer 2 for inputting print data sent from the host computer 1.
And the print data input to the input buffer 2 is CP
Given to U12.

The CPU 12 reads print data from the input buffer 2 based on a PDL analysis program stored in the program ROM 4, analyzes the read print data, and from the analysis result, halftone image information (page object information). Create.

In creating the halftone image information, the color conversion means 7 is used.
The display color RGB (additive color mixture) included in the print data is converted to YMCK (subtractive color mixture) used in the interpreter process of the printer, and the character code included in the print data is stored in the font ROM 3. Convert to font data such as outline font. This halftone image information is temporarily stored in the management RAM 5 together with global information, and the page object whose color drawing is full bitmap data is stored in the object buffer 6.

The generated halftone image information is given to the hard renderer 8. The hard renderer 8 is an ASIC that executes rendering processing on halftone image information in real time in synchronization with the video signal transfer of the printer I / F 10.
It consists of a hardware configuration. The processing result of the rendering processing for the halftone image information is written in the page buffer 9, and the writing operation is performed in parallel with the page buffer 9.
A banding process is executed to read the process result stored in the. This rendering process is a process called a band rendering process with color information specified by print data, resolution and color gradation based on preset processing capability, and this process will be described later.

When the banding process cannot be executed, the degradation process is set to be executed. In this degrading process, a full bit map memory having a capacity that can be acquired from the page buffer 9 is acquired, and a rendering process with a resolution and color gradation corresponding to the acquired capacity of the full bit map memory is executed on the halftone image information. Then, the result of the rendering process is written in the full bit map memory acquired in the page buffer 9, and the result of the rendering process held in the full bit map memory is sent to the printer 13 by the printer I / F 10.
Is a video signal supplied via the.

In this degrading process, the gradation of the bit data of the color multi-valued information is reduced while maintaining the resolution of the color multi-valued information included in the print data, and the result of the rendering process for the halftone image information is full bit. The rendering process that is set to write in the map memory and is performed during this degradation process is called degradation rendering. A dither process is used as a process for compensating for the deterioration of the gradation of the bit data in the degraded rendering.
Performed by

The printer 13 forms an image represented by the video signal transferred via the printer I / F 10 on a sheet.

Next, the rendering process will be described with reference to FIG. FIG. 3 is a flowchart showing a rendering process executed by the print control apparatus of FIG.

Referring to FIG. 3, first, the interpreter task 210 executes steps S301 to S3.
The processes up to 05 are sequentially executed.

In step S301, print data (PDL data) is input from the host computer 1, and in subsequent step S302, the command included in the print data is analyzed. Specifically, various drawing commands such as mask, background, and logical drawing are analyzed.

Then, step S303 is executed to convert the analysis result into halftone image information (object information) having a structure suitable for high-speed hardware rendering. At the time of this conversion, the page buffer 9 is divided into a plurality of band areas so that banding processing can be performed.

In the subsequent step S304, the decoding time of data required for rendering and the rendering time are added each time an object is created in each band, and the rendering time is predicted.

Then, in step S305, it is determined whether or not the analysis of the PDL command for one page in the interpreter task 210 has been completed. When the analysis of the PDL command for one page is completed, the process moves to the next renderer task 211, and when the analysis of the PDL command for one page is not completed, the above step S302 is performed to analyze the next command. The process from is repeated.

Upon shifting to the renderer task 211, it is first determined in step S306 whether banding processing is possible. If the banding process is possible, step S308 is executed to perform band rendering.
If the banding process is not possible, step S307 is executed and the degraded rendering is performed.

Next, the banding process will be described with reference to FIG. 2. FIG. 2 is a diagram schematically showing the banding process executed by the print control apparatus of FIG.

In the band rendering by the renderer task 211 described above, as shown in FIG.
The page object created in the management RAM 5 by the command analysis process (steps S302 and 303) is read by the hard renderer 8.

After reading the page object, the scan line information (X
min, Xmax) is extracted, and the corresponding background information is written in each band (0, 1, ...) Of the page buffer (band buffer) 9 with reference to the current background information and the logical drawing mode.

Next, rendering is executed while changing the Y information so as to correspond to all the masks. In this embodiment, since a color printer is assumed, the page buffer 9 has four planes, that is, YMCK planes, and the rendering for the color information is executed for each plane.

As described above, the hard renderer 8 renders the page object with the band number i according to the mask information, the background information, and the logical drawing method, and at the same time, outputs the horizontal synchronization signal from the printer 13. According to the printer I / F10
The band information of the band number i-1 that has already been rendered via the video signal is a video signal (YMCK color video signal).
Is sent to the printer 13.

Next, the degraded rendering will be described with reference to FIG. FIG. 4 is a flow chart showing the degradation rendering processing executed by the print control apparatus of FIG.

As described above, when the process shifts to the renderer task 211, it is determined whether or not the banding process is possible as a pre-process for rendering (step S30).
6). This banding process becomes impossible in the following cases.

(1) When an instruction that cannot execute rendering by banding, such as a Flood fii instruction (point designation fill instruction), exists in the page.

(2) Management R by inputting a large amount of images
When the capacity of AM5 overflows (memory degradation).

(3) In a color printer such as an electrophotographic laser beam printer, once paper is fed and recording is started, banding processing is performed to supply a video signal to the printer 13 and render to a band. It is necessary to process in parallel, but the above step S
When the rendering time of one of the bands within the rendering time of each band obtained in 304 exceeds a predetermined threshold.

If the above conditions are met, it is determined that the banding process is not possible, and the degraded rendering is performed (step S307).

In this degraded rendering, a full bit map memory having a capacity that can be acquired from the page buffer 9 is acquired, and the resolution of the color multi-valued information included in the print data is maintained while the level of the bit data of the color multi-valued information is maintained. Rendering is performed with a reduced degree of furniture, and the processing result is written to the full bitmap memory. The process of executing the degradation rendering is called the degradation process.

Next, the processing flow of the degraded rendering will be described with reference to FIG. FIG. 4 is a flowchart showing the processing of the degraded rendering executed by the print control apparatus of FIG.

In the degraded rendering, since the rendering cannot be executed in real time, the full bitmap (bit depth 1, bit depth 1,
Rendering is performed on the page buffer 9 corresponding to 2, 4 or 8 bits).

Referring to FIG. 4, first, step S40.
Input data (8 bits) with 1. Continuing step S4
In 02, in order to acquire a full bitmap memory of a capacity that can be acquired from the page buffer 9, the number of gradations of bit data that can be acquired in the bitmap memory while maintaining the resolution of color multi-valued information included in print data ( 1, 2,
4 or 8 bits). In this determination, if there is a RAM added by the user, the number of gradations of bit data is selected so as to increase the output bit gradation of the full bit map from the existing memory capacity by adding the RAM capacity. For example, 1M × 4 (color) × 8bi
If 8 MB of full bitmap memory can be acquired from t = 32 MB of input data, the number of output bits is determined to be 2 bits. If 16 MB of full bitmap memory can be acquired, the number of output bits is 4. Judged as a bit.

Then, step S403 is executed to obtain the full bit map memory corresponding to the selected number of bit gradations, and in the following step S404, the gradation of the data is converted into the bit gradation selected by the dither processing. To do.

Next, in step S405, the full bitmap memory, that is, is written and stored.

In step S406, the data stored in the page buffer 9 is read out and transferred to the printer 13.

In this way, the gradation conversion of the page object is performed by executing the above steps 402 to 405.

Next, the dither processing for outputting multi-value will be described with reference to FIGS. 5 and 6. 5 is a diagram showing the principle of the dither processing by the hardware in the print control apparatus of FIG. 1, and FIG. 6 is a diagram showing the input / output relationship in the dither processing by the hardware of the print control apparatus of FIG. is there. In the present embodiment, the dither processing for outputting multi-values will be described by taking an example of converting 8-bit (256 levels) input as multi-values to 2 bits (4 levels).

First, the principle of the dither processing for outputting multivalues will be described with reference to FIG.

When the input value of the pixel of interest is less than 64, 0 (00) is output as shown in FIG. 5 (a). If the input value of the pixel of interest is 64 or more and less than 128,
If 85 (01) has an input value of 128 or more and less than 192, 170 (10) is output, and if its input value is 255 or less, 255 (11) is output.

As can be seen from FIG. 5A, inside the AREA to which the input belongs, the multi-thresholds (64, 128, 192) in the AREA are used and the output is AREA.
The binarization process is performed so as to be at both ends of. In the figure, the thick solid line in the vertical direction indicates the division of the area, and the numerical values described below the solid line and the numerical values in parentheses represent the output. Numerical value 8 described below the solid line
It is a bit level numerical value, and the numerical value in parentheses is a 2-bit level numerical value. Also, the thin vertical lines are the AREA
8 shows the threshold value for the 8-bit level.

An example in which the binarization process is applied to a dither that outputs multiple values will be described with reference to FIGS. 5B and 5C.

Referring to FIGS. 5B and 5C, the data of the pixel of interest (rectangular portion shown by hatched lines) in the input data and the dither matrix corresponding to the pixel of interest (see FIG. The threshold value suitable for the area is calculated from the value of () shown in c), and the data of the target pixel is binarized with the threshold value. This dither matrix repeats the same pattern on the page buffer as a 4 × 4 pattern, and the maximum value of the dither matrix is 255 / (bit level-
1).

When the input data is scaled up or down, the resolution of the processed data is already converted into the resolution of the page memory.

Next, the algorithm of the dither processing for outputting the actual multi-value will be described with reference to FIGS. 5 and 6.

Referring to FIG. 5, first, the pixel of interest in the input data is read, and the ARE of the pixel of interest is read.
It is determined whether it belongs to A (first processing). In this example, the pixel of interest is 180, and the pixel belongs to AREA2.

Next, the value of the corresponding dither matrix is read, and the value is changed to the threshold value that matches this AREA (second processing). In this example, the threshold is 74 + 85 ×
2 = 244.

Next, if the pixel data of interest is equal to or greater than the threshold value, the maximum value of this AREA is set as the output value, and if the pixel data of interest is less than the threshold value, the minimum value of this AREA is set as the output value. Process 3). In this example, the pixel of interest (18
0) <threshold value (244), the minimum AREA value 170 is output.

Next, pixel processing is performed (fourth processing). This processing can be performed at high speed by hardware by using a look-up table. In this lookup table, 2-bit output values obtained by dither-converting each position of the 4 × 4 dither matrix for each input level from 0 to 255 are stored in advance. The size of this lookup table is Y
A size of 256 × 4 × 4 × 2 bits = 1024 bytes is required for each MCK, and the dither matrix table indicated by the pointer shown in FIG. 6A is shown in units of 2 bits (shown in FIG. 6B). Accessed from.

Similarly, the above-mentioned first, second, third, and fourth processes are executed for 15 AREAs obtained by dividing the above 8-bit level into 15, thereby dithering to 4 bits (16 values). Is realized.

As described above, when it is determined that the banding process is not possible, the degrading rendering is performed (step S307), and in this degrading rendering, the full bit map memory having the capacity that can be obtained from the page buffer 9 is acquired. While maintaining the resolution of the multi-valued color information included in the print data, the gradation of the bit data of the multi-valued color information is reduced and rendering is executed, and the processing result is written to the full bitmap memory. It is possible to suppress the deterioration of the image quality of the output image due to the degradation processing).

Further, if there is a RAM added by the user in order to obtain a full bitmap memory having a capacity obtainable from the page buffer 9, the RAM capacity is added to output the full bitmap from the existing memory capacity. Since the number of gradations of the bit data is selected so that the bit gradation is as large as possible, the deterioration of the number of gradations of the bit data can be suppressed, and the deterioration of the image quality can be further suppressed.

In the present embodiment, an example of the print control device of the color printing device which is connected to the host computer 1 in a one-to-one manner has been described. It goes without saying that the principle of the present invention can be applied to the print control device of the printing device that receives the print data of.

In the present embodiment, 8-bit full-color multi-valued information is used during banding processing, and the bit gradation is set to drop during degradation. However, the data whose bit gradation is dropped during banding processing is used. It is needless to say that the principle of the present invention can be applied to a print control apparatus that creates full bitmap data with a lower bit gradation than when banding processing is performed when printing is performed and degradation occurs.

Further, although the present embodiment has been described on the assumption that the gradation is lowered during the degrading process, if the full bit map memory for 256 gradations can be acquired by the user's additional RAM, the gradation is degraded during the degrading process. It is not necessary to perform pseudo gradation processing conversion by dither processing.

Furthermore, the principle of the present invention can be applied to a print control device of a monochrome printing device capable of multi-value output.

[0079]

As described above, according to the print control apparatus of the first aspect, the resolution of the color multi-valued information included in the input information of the predetermined page description language system is maintained during the degradation processing. However, since the gradation of the bit data of the color multi-valued information is reduced and the result of the rendering processing for the intermediate information is written in the bitmap memory, it is possible to suppress the deterioration of the image quality of the output image due to the degradation processing. it can.

According to the print control apparatus of the second aspect, the determination means is based on the color information designated by the input information including the multi-valued color information of the predetermined page description language system, and the preset processing capability. Since it is determined whether or not the banding means can be executed based on at least one of the time required for the rendering process based on the resolution and the color gradation and the capacity of the storage means for the intermediate information, it is possible to reliably determine whether or not the banding means can be executed. You can

According to the print control apparatus of the third aspect, since the dither processing is used as the processing for compensating for the deterioration of the gradation of the bit data of the color multi-valued information, the deterioration of the gradation of the output image due to the degradation processing is performed. Can be compensated, and the deterioration of the image quality of the output image can be further suppressed.

According to the print control control method of the fourth aspect, at the time of the degrading process, the resolution of the color multi-value information included in the input information of the predetermined page description language system is maintained and the color multi-value information of the color multi-value information is maintained. Since the gradation of the bit data is reduced and the result of the rendering process for the intermediate information is written in the bitmap memory, it is possible to suppress the degradation of the image quality of the output image due to the degradation process.

According to the print control method of the fifth aspect, the determination means is based on the color information designated by the input information including the color multi-valued information of the predetermined page description language system, and the preset processing capability. Since it is determined whether or not the banding means can be executed based on at least one of the time required for the rendering process based on the resolution and the color gradation and the capacity of the storage means for the intermediate information, it is possible to reliably determine whether or not the banding means can be executed. You can

According to the print control method of the sixth aspect, since the dither processing is used as the processing for compensating for the deterioration of the gradation of the bit data of the color multi-valued information, the deterioration of the gradation of the output image due to the degradation processing is performed. Can be compensated, and the deterioration of the image quality of the output image can be further suppressed.

According to the color printing apparatus of claim 7,
During the degradation process, while maintaining the resolution of the multi-valued color information included in the information of the specified page description language method, the gradation of the bit data of the multi-valued color information is reduced, and the result of the rendering process for the intermediate information Is written in the bitmap memory, it is possible to suppress the deterioration of the image quality of the output image due to the degradation process.

According to the color printing apparatus of the eighth aspect,
For the color information designated by the information including the color multi-valued information of the input predetermined page description language method by the determination means, the time and intermediate information required for the rendering processing with the resolution and color gradation based on the preset processing ability Since it is determined whether or not the banding means can be executed based on at least one of the capacity of the storage means, it is possible to reliably determine whether or not the banding means can be executed.

According to the color printing apparatus of the ninth aspect,
Since the dither processing is used as the processing for compensating the deterioration of the gradation of the bit data of the color multi-valued information, the deterioration of the gradation of the output image due to the degradation processing can be compensated for, and the deterioration of the image quality of the output image can be prevented. It can be further suppressed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a color printing apparatus equipped with an embodiment of a print control apparatus of the present invention.

FIG. 2 is a diagram schematically showing a banding process executed by the print control apparatus of FIG.

FIG. 3 is a flowchart showing a rendering process executed by the print control apparatus of FIG.

FIG. 4 is a flowchart showing a process of degraded rendering executed by the print control apparatus of FIG.

5 is a diagram showing a principle of dither processing by hardware in the print control apparatus of FIG.

FIG. 6 is a diagram showing an input / output relationship in a dither process by hardware in the print control apparatus of FIG.

[Explanation of symbols]

 1 Host Computer 5 Management RAM 6 Object Buffer 8 Hard Renderer 9 Page Buffer 10 Printer I / F 11 Dither 12 CPU 13 Printer 14 Print Control Device

Claims (9)

[Claims] 1. Analysis of input information including color multi-valued information of a predetermined page description language method, creation of halftone image information based on the analysis result, and storage of processing results by rendering processing on the halftone image information. Banding processing means for executing an operation of reading the processing result held in the storage means as image data to be supplied to the printing device in parallel with the writing operation to the means, and the input predetermined page description language color A determination unit that determines whether or not the banding process can be performed on the information including the value information, and if it is determined that the banding process unit can be executed, the input multi-value color of the predetermined page description language method Rendering processing with color information specified by information including information, resolution and color gradation based on preset processing capacity The intermediate information is controlled to be executed, and when it is determined that the banding processing means cannot be executed, a compensating means is controlled to execute the degrading processing. A bitmap memory having a capacity that can be acquired from the storage unit is acquired, rendering processing with resolution and color gradation corresponding to the acquired capacity of the bitmap memory is performed on the intermediate information, and the result of the rendering processing is described above. In a print control device that writes the result of the rendering process held in the bitmap memory acquired in the storage means to the printing device as image data to be supplied to the printing device, during the degradation process, the input Maintains the resolution of color multi-valued information included in the information of a predetermined page description language method. Want the print control apparatus to reduce the gradient of the bit data of the color multivalued information and writes the result of the rendering process on the intermediate information to the bit map memory. 2. The determining means renders color information specified by the input information including color multi-valued information of a predetermined page description language method, rendering processing based on resolution and color gradation based on preset processing capability. 2. The print control apparatus according to claim 1, wherein whether or not to execute the banding means is determined based on at least one of a time required for the intermediate information and a capacity of the storage means for the intermediate information. 3. The print control apparatus according to claim 1, wherein a dither process is used as a process for compensating for a decrease in gradation of bit data of the color multi-valued information. 4. Analysis of input information including color multi-valued information of a predetermined page description language method, creation of halftone image information based on the analysis result, and storage of processing results by rendering processing for the halftone image information. Banding processing means for executing the operation of reading the processing result held in the storage means as image data to be supplied to the printing device in parallel with the writing operation to the means, and the input predetermined page description language color A determination unit that determines whether or not the banding process can be performed on the information including the value information, and if it is determined that the banding process unit can be executed, the input multi-value color of the predetermined page description language method Rendering processing with color information specified by information including information, resolution and color gradation based on preset processing capacity The intermediate information is controlled to be executed, and when it is determined that the banding processing means cannot be executed, a compensating means for controlling the degrading processing is provided. A bitmap memory having a capacity that can be acquired from the storage unit is acquired, rendering processing with resolution and color gradation corresponding to the acquired capacity of the bitmap memory is performed on the intermediate information, and the result of the rendering processing is described above. In a print control method of writing to a bitmap memory acquired in a storage unit and using the result of the rendering processing held in the bitmap memory as image data to be supplied to the printing apparatus, the input is performed during the degradation processing. Maintains the resolution of color multi-valued information included in the information of a predetermined page description language method. Reluctant print control method that color to reduce the gradient of the bit data of the multi-level information and writes the result of the rendering process on the intermediate information to the bit map memory. 5. The rendering means uses the color information designated by the input information including color multi-valued information of a predetermined page description language method, a rendering process based on a resolution and a color gradation based on a preset processing capability. 5. The print control method according to claim 4, wherein whether or not the banding means can be executed is determined based on at least one of a time required for the intermediate information and a capacity of the storage means for the intermediate information. 6. The print control method according to claim 4, wherein a dither process is used as a process for compensating for a decrease in gradation of bit data of the color multi-valued information. 7. An analysis of input information including color multi-valued information of a predetermined page description language method, creation of halftone image information based on the analysis result, and storage of processing results by rendering processing for the halftone image information. Banding processing means for executing an operation of reading the processing result held in the storage means as image data for forming an output image in parallel with the writing operation to the means, and the input predetermined page description language method. A determination unit that determines whether or not the banding process can be performed on the information including the multi-valued color information, and if it is determined that the banding process unit can be executed, the color of the input predetermined page description language method is determined. Rendering with color information specified by information including multi-valued information, resolution and color gradation based on preset processing capacity Compensating means for controlling the processing to be executed on the intermediate information, and controlling to execute the degrading processing when it is determined that the banding processing means cannot be executed. , Acquiring a bitmap memory having a capacity that can be acquired from the storage means, performing a rendering process on the intermediate information with a resolution and a color gradation corresponding to the acquired capacity of the bitmap memory, and outputting the result of the rendering process. In the bitmap memory acquired in the storage means, and in the color printing apparatus in which the result of the rendering processing held in the bitmap memory is the image data, during the degradation processing, the input predetermined page While maintaining the resolution of color multi-valued information included in the description language method, Color printing apparatus which reduce the gradient of the bit data of the color multi-value information and writes the result of the rendering process on the intermediate information to the bit map memory. 8. The determination unit is a color information specified by the input information including color multi-valued information of a predetermined page description language method, a rendering process based on a resolution and a color gradation based on a preset processing capability. 8. The color printing apparatus according to claim 7, wherein whether or not the banding means can be executed is determined based on at least one of the time required for the intermediate information and the capacity of the storage means for the intermediate information. 9. The color printing apparatus according to claim 7, wherein a dither process is used as a process for compensating for a decrease in gradation of bit data of the color multi-valued information.