JPH11196246A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device that supplies a high quality image where resolution of characters and gradation of photographs are made compatible. SOLUTION: A raster processing section 8 generates image data based on contents analyzed by an interpreter 14 to analyze input data and stores the data to an image data memory 9, and at the same time, attribute data of the input data are stored in an attribute discrimination memory 16. An image expansion section 10 expands the image data stored in the image data memory 9 and outputs from an engine interface 12 the expanded data with the attribute data stored in the attribute discrimination memory 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus for performing gradation printing of full color or the like.

[0002]

2. Description of the Related Art Conventionally, printers based on various principles have been proposed as output terminals of personal computers, workstations, and the like. In recent years, in particular, a color laser beam printer (hereinafter referred to as C) using an electrophotographic process and a laser exposure technique has been proposed. -LBP) is superior in terms of recording speed and print quality, and is rapidly spreading. Furthermore, demands for image quality are increasing, and not only graphics data but also continuous tone image data is being output. On the other hand, as a printer engine, a print engine emphasizing the gradation represented by a digital copying machine (hereinafter referred to as D-PPC) and a printer engine emphasizing the resolution represented by C-LBP have become widespread. However, multifunction peripherals having functions such as a printer, a copying machine, and a facsimile appear, and a print engine having both a mode emphasizing gradation and a mode emphasizing resolution has been proposed.

FIG. 7 is a schematic diagram of a conventional image forming apparatus. The image forming apparatus 1 has a controller unit 5 which develops a printer code 3 sent from a host computer 2 as image data to form an image recording signal 4. And a printer engine 6 for forming a recorded image from the image recording signal 4. FIG. 8 is a block diagram of a conventional controller unit 5. The communication interface 7 performs communication with the host computer 2 and receives the printer code 3. The rasterizing unit 8 interprets the printer code 3 and outputs BK (black), Y (yellow), M (magenta), C
The developed image information is compressed and written in the image data memory 9 composed of four blocks for recording each image data of (cyan). The image decompression unit 10 includes an image data memory 9
The compressed image information is expanded according to the printing speed of the printer engine 6 and output to the gradation processing unit 11. The gradation processing unit 11 performs processing for stabilizing the gradation of the printer engine in addition to processing such as image density adjustment, gamma correction, and screen angle. The engine interface 12 has a role of transmitting the image recording signal 4 output from the gradation processing unit 11 to the printer engine 6.

[0004]

However, in the above-described conventional configuration, all the image data are image-developed and stored in the same memory, that is, the image data memory 9, so that a high-quality image according to the attribute of the image data is obtained. It has been difficult to output images.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus capable of outputting a high-quality image in which resolution of characters and the like and gradation of a photograph and the like are compatible.

[0006]

In order to solve the above-mentioned problems, an image forming apparatus according to the present invention stores analysis means for analyzing attributes of input data and attribute data of the input data analyzed by the analysis means. Attribute storing means, developing means for expanding the input data into image data based on the analysis result, data storing means for storing the developed image data, and image data and attribute storing means stored in the data storing means. Output means for outputting the stored attribute data to an external printing means.

In the image forming apparatus according to the present invention, the analyzing means analyzes the attribute of the input data, and the analyzed attribute data is output to the external printing means together with the image data. For this reason, the printing unit can set the resolution and gradation of the image data with reference to the attribute data and perform printing, and can perform printing according to the attribute of the input data.

[0008]

An image forming apparatus according to a first aspect of the present invention comprises: an analyzing unit for analyzing attributes of input data; an attribute storing unit for storing attribute data of the input data analyzed by the analyzing unit; Expanding means for expanding the input data into image data based on the result; data storing means for storing the expanded image data; and image data stored in the data storing means and attribute data stored in the attribute storing means. Output means for outputting to an external printing means.

Thus, the input data is developed into image data according to the attribute, and the attribute data and the image data are output to an external printing means to perform the printing operation at the resolution or gradation corresponding to the attribute. Becomes possible.

According to a second aspect of the present invention, in the image forming apparatus of the first aspect, the data storage means stores the image data in page units.

Thus, the image data can be stored for each page and output to an external printing means.

According to a third aspect of the present invention, in the image forming apparatus of the first aspect, the data storage means stores the image data in band units.

Thus, the configuration of the storage means such as a memory for storing image data can be reduced in size.

According to a fourth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects of the present invention, the attribute storage means stores the attribute data in pixel units of the image data. It is something to memorize.

This makes it possible to set the resolution and gradation according to the attribute for each pixel of the image data by an external printing means, and to print a high-quality image.

According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to third aspects of the present invention, the attribute storage means stores one of the image data.
Alternatively, it stores attribute data in a plurality of ladder units.

Thus, the data amount of the attribute data can be reduced, and the capacity of the attribute storage means can be saved.

According to a sixth aspect of the present invention, there is provided an image forming apparatus, comprising: analyzing means for analyzing attributes of input image data;
An attribute storage unit for storing attribute data of the image data analyzed by the analysis unit, a data storage unit for storing the image data, and an image data stored in the data storage unit and an attribute data stored in the attribute storage unit. And output means for outputting to the printing means. This makes it possible to analyze and output the attributes of the input data expanded into the image data, and to obtain a high-quality image by setting the resolution and gradation according to the attributes in an external printing unit. .

According to a seventh aspect of the present invention, in the configuration of the image forming apparatus according to the sixth aspect of the present invention, the attribute storage means stores attribute data of the image data in units of pixels.

Thus, it is possible to set the resolution and gradation according to the attribute for each pixel of the image data by the external printing means, and it is possible to print a high quality image.

According to an eighth aspect of the present invention, in the image forming apparatus according to the sixth aspect of the present invention, the attribute storage means stores one or a plurality of raster unit attribute data of the image data. It is.

Thus, the data amount of the attribute data can be reduced, and the capacity of the attribute storage means can be saved.

According to a ninth aspect of the present invention, in the configuration of the image forming apparatus according to any one of the first to eighth aspects, the output means includes an image data read from the data storage means. Output the attribute data read from the attribute storage means in synchronization with the output of the attribute data.

Thus, the external printing means can appropriately set the resolution and gradation based on the attribute data and obtain a high quality image.

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram illustrating the controller unit 5. The communication interface 7 performs communication with the host computer 2 and receives the printer code 3. There are several types of printer codes 3 depending on the printer, such as a printer control language and a page description language. The printer engine 6 is a laser-exposed color electrophotographic system, and includes a gradation processing unit 11 and a printing mechanism 13.
Graphics mode with 300x600D recording density
At the recording density of PI, each color can be printed in a multi-value mode with 256 gradations per pixel.

The interpreter 14 interprets the printer code 3, develops a print image for each color by the rasterizing unit 8, compresses the print image into the image data memory 9, writes the compressed image in the image data memory 9, and writes “0” or “0” representing the attribute in the attribute determination memory 16. The determination data of "1" is written. The image decompression unit 10 decompresses the image information in the image data memory 9 and the attribute discrimination memory 16 according to the resolution of the printer engine 6. The engine interface 12 has a function of sending the image recording signal 4 output from the image decompression unit 10 to the printer engine.

In the printer engine 6, the gradation processing section 11 performs processing for stabilizing the gradation of the printer engine 6, in addition to processing such as image density adjustment, gamma correction, and screen angle.

FIG. 2 is a flowchart of the processing of the rasterizing unit and the intermediate interpreter unit according to the first embodiment of the present invention. Hereinafter, processing procedures of the rasterizing unit 8 and the interpreter unit 14 of the present invention will be described with reference to the flowchart of FIG.

First, in step S1, it is checked whether or not there is a printer code 3 from the host computer 2.
If there is, the printer code 3 is received in step S2.

In step S3, the interpreter unit 14
It is determined whether or not the printer code 3 is a page end code. If the printer code 3 is not the page end code, the process proceeds to step S4, where it is determined whether or not the printer code 3 is a code relating to image development. If the printer code 3 is a code related to image development, an intermediate text is generated and written to the text memory 15.

If the printer code 3 is a page end code, an intermediate text for one page is generated in step S5, and a flag indicating that there is a page waiting to be printed is set.

In step S6, it is checked whether there is a page waiting for printing, and if not, the process returns to step S1. If there is a page waiting to be printed, it is checked in step S7 whether there is an empty page memory in the image data memory 9, and if not, the process returns to step S1. If there is an empty page memory, in step S8, all the intermediate texts for one color are developed into image data of the print image and written to the page memory. When writing is completed, it is checked in step S9 whether the development for all colors has been completed. If not completed, the process returns to step S7. If completed, the printing operation is started in step S10.
Returning to step S1, the same operation is repeated.

Next, the development of the image data for one color in step S8 will be described in detail. FIG. 3 is an explanatory diagram of the gradation modulation process. If the image data is graphics data, as shown in FIG. 3A, four colors (BK (black), 600 × 600 DPI, which is the resolution of the printer engine 6,
The image data is developed as Y (yellow), M (magenta), C (cyan)). The expanded image data is written into the image data memories 9 of the four colors, and at the same time, the printer code is written to the address of the attribute determination memory 16 corresponding to the address of the image data memory 9 where the expanded image data is written. “0” indicating that 3 is graphics data is written. Similarly, when the printer code 3 is not graphics, four colors of 600 × 600 DPI (B
The image data is developed as K (black), Y (yellow), M (magenta), C (cyan)). The expanded image data is written to the image data memory 9 and at the same time, the printer code 3 is transferred to the address of the attribute determination memory 16 corresponding to the address of the image data memory 9 where the expanded image data is written. "1" indicating that the image data is the image data is written.

After the completion of the development process for the four colors, if the printer engine 6 is ready, printing is started.
In the present embodiment, the image data in the image data memory 9 for each color is not sent to the printer engine 6 via the engine interface 12 as it is, but the image decompression unit 1
0, the engine interface 12
To the printer engine 6 as an image recording signal 4 together with the attribute discrimination signal.

Hereinafter, the image decompression unit 10 and the gradation processing unit 11 of the printer engine 6 will be described.

The image decompression unit 10 decompresses the image data stored in the image data memory 9 one by one in accordance with the order of colors to be printed by the printer engine 6. The printer engine 6 performs printing in the order of BK (black), C (cyan), M (magenta), and Y (yellow). BK
The image recording signal 4 necessary for printing (black) is composed of the BK (black) image data in the image data memory 9 and the attribute discrimination memory 16.
And only C (cyan), M (magenta), and Y (yellow) image data are not required.
For the other colors, the image recording signal 4 is expanded by the image expansion unit 10 using the image data corresponding to each color in the image data memory 9 and the information in the attribute determination memory 16.

FIG. 4 is a block diagram of an image decompression unit. An image data signal 18 from an image data memory 9 is separated into graphics data and image data by a demultiplexer 19 by an attribute discrimination signal 17 from an attribute discrimination memory 16. The graphics data is processed by the graphics data decompression unit 20, and becomes image data of 600 × 600 DPI and 256 continuous tones. Further, the image data is processed by the multi-value dither data decompression unit 21, and the 600 × 600
The image data becomes continuous gradation image data of 256 gradations by the DPI, is synthesized by the multiplexer 22 and becomes an image expansion signal 23, and is sent to the gradation processing unit 11 via the engine interface unit 12. Here, the graphics data decompression unit 20 not only converts the data into 256 gradation data at 600 DPI, but also performs the smoothing of the edges of the characters and line drawings.

The gradation processing section 11 of the printer engine 6
Although processing such as image density adjustment and gamma correction is performed, the central point is that the gradation modulation processing is switched based on the attribute determination signal 17. When the attribute discrimination signal 17 is “0” indicating graphics, gradation modulation is performed for each pixel as shown in FIG. 3A, dots of each pixel are uniformly grown, and the attribute discrimination signal 17 is In the case of "1" indicating an image, as shown in FIG. 3B, blocks are formed every two pixels, and dots are grown in units of two pixels to stabilize gradation.

As described above, the printer engine 6
In accordance with the attribute determination signal 17, gradation processing is performed in accordance with the graphic data and the photograph / dot data, so that it is possible to achieve both the resolution of the graphic data and the gradation of the photograph / dot image.

The printer is not limited to the electrophotographic system using a laser beam according to the present embodiment, but may be a thermal transfer system, an ink jet system, or the like. A shutter system or the like may be used.

In this embodiment, the printer code 3 from the host computer 2 is taken as an example of the image information source, but the image information source may be an image file or a video image signal. Absent.

Further, in the present embodiment, an example of writing attribute information in pixel units in the attribute determination memory 16 has been taken as an example. However, in order to reduce the capacity of the attribute determination memory 16, one piece of attribute information is stored in one raster. It may be provided, or one piece of attribute information may be provided in units of a plurality of rasters.

In this embodiment, the interpreter 1
4 corresponds to the analysis means of the present invention, the attribute determination memory 16 corresponds to the attribute storage means, the image data memory 9 or the band memory 24 (see Embodiment 2) corresponds to the data storage means, and the engine interface 12 corresponds to It corresponds to output means. The same applies to the second embodiment below.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a block diagram illustrating the controller unit 5,
The communication interface 7 communicates with the host computer 2 and receives the printer code 3. There are several types of printer codes 3 depending on the printer, such as a printer control language and a page description language. Printer engine 6
Is a color electrophotographic method of laser exposure, and a gradation processing unit 11 is used.
Graphics mode with a recording density of 600 × 600 DPI and 300 × 600 DPI
Each color can be printed in a multi-value mode with 256 gradations per pixel at a recording density of.

The interpreter unit 14 interprets the printer code 3 and converts it into an intermediate text consisting of a character type, a graphic type, a style, a printing position, and the like.
Write to The intermediate text written in the text memory 15 is developed into a print image for each color by the rasterizing unit 8, and is written in the band memory 24.
The determination data of “0” or “1” representing the attribute is written in the attribute determination memory 16. The image decompression unit 10 decompresses the image information in the band memory 24 and the attribute discrimination memory 16 according to the resolution of the printer engine 6. The engine interface 12 has a role of transmitting the image recording signal 4 output from the image decompression unit 10 to the printer engine 6. The gradation processing unit 11 performs processing for stabilizing the gradation of the printer engine 6 in addition to processing such as image density adjustment, gamma correction, and screen angle.

The difference between the second embodiment and the first embodiment is that the intermediate text written in the text memory 15 is developed into a print image for each color by the rasterizing section 8 and is written in the band memory 24 to determine the attribute. The determination data of “0” or “1” representing the attribute is written in the memory 16, and the other parts are the same as in the first embodiment.

Embodiment 3 Hereinafter, Embodiment 3 of the present invention will be described with reference to FIG.

FIG. 6 is a block diagram for explaining the controller unit 5 and shows an example in which the present invention is applied to a printing apparatus of the type utilizing host computer resources.

The only difference from the second embodiment is that image data and discrimination information created on the host computer are analyzed by the interpreter unit 14 and written into the image data memory 9 and the attribute discrimination memory 16. Is the same as in the second embodiment.

[0050]

As described above, according to the present invention, in an image forming apparatus such as a printer or a copying machine that performs full-color print output, it is possible to achieve both resolution of characters and the like and gradation of a photographic image. be able to.

The image data is stored in the data storage means in page units or band units, and the attribute data is stored in the attribute storage means, and the image data and the attribute data are output in synchronization with each other. And the printing speed can be improved.

Further, by using the resources of the host computer and generating the image data and the attribute discrimination data on the host computer side, the resolution of characters and the like and the gradation of photographic images and the like can be reduced with less hardware resources. Can be achieved.

Further, by writing attribute data in units of one or more rasters in the attribute storage means, the capacity of the attribute storage means can be further reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a controller unit.

FIG. 2 is a flowchart of processing performed by a rasterizing unit and an intermediate interpreter unit according to the first embodiment of the present invention;

FIG. 3 is an explanatory diagram of gradation modulation processing.

FIG. 4 is a block diagram of an image decompression unit.

FIG. 5 is a block diagram illustrating a controller unit.

FIG. 6 is a block diagram illustrating a controller unit.

FIG. 7 is a schematic diagram of a conventional image forming apparatus.

FIG. 8 is a block diagram of a conventional controller unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Host computer 3 Printer code 4 Image recording signal 5 Controller unit 6 Printer engine 7 Communication interface 8 Rasterize part 9 Image data memory 10 Image decompression part 11 Gradation processing part 12 Engine interface 13 Printing mechanism 14 Interpreter part 15 Text Memory 16 Attribute determination memory 19 Demultiplexer 20 Graphics data decompression unit 21 Multi-valued dither data decompression unit 22 Multiplexer 24 Band memory

Claims (9)

[Claims] An analyzing means for analyzing an attribute of input data;
Attribute storing means for storing attribute data of the input data analyzed by the analyzing means, developing means for developing the input data into image data based on the analysis result, and data storage for storing the developed image data And an output unit for outputting the image data stored in the data storage unit and the attribute data stored in the attribute storage unit to an external printing unit. 2. An image forming apparatus according to claim 1, wherein said data storage means stores said image data in page units. 3. An image forming apparatus according to claim 1, wherein said data storage means stores said image data in band units. 4. The image forming apparatus according to claim 1, wherein said attribute storage means stores attribute data of said image data in pixel units. 5. An image forming apparatus according to claim 1, wherein said attribute storage means stores attribute data of one or a plurality of ladders of said image data. 6. An analyzing means for analyzing attributes of input image data, an attribute storing means for storing attribute data of the image data analyzed by the analyzing means,
Data storing means for storing the image data, and output means for outputting the image data stored in the data storing means and the attribute data stored in the attribute storing means to an external printing means. Characteristic image forming apparatus. 7. An image forming apparatus according to claim 6, wherein said attribute storage means stores attribute data of said image data in pixel units. 8. An image forming apparatus according to claim 6, wherein said attribute storage means stores attribute data of one or more raster units of said image data. 9. The image processing apparatus according to claim 1, wherein said output means outputs said attribute data read from said attribute storage means in synchronization with output of said image data read from said data storage means. An image forming apparatus according to any one of claims 1 to 8.