JP3260803B2 - Image processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for inputting a page description language (PDL) code containing color information, forming a multi-valued color image, and outputting a multi-valued color. It is.

[0002]

2. Description of the Related Art Conventionally, in a color image drawing apparatus which inputs a PDL code including color information, forms a multi-valued color image from the input PDL code, and outputs a full-color image, a multi-valued color image for one page is used. A storage circuit capable of storing an image is provided, and a multi-valued color image formed from a PDL code is drawn and output there. A PDL code can hold information such as positions, shapes, colors, and fonts of figures and characters with a small amount of information, and can process image information including complicated figures and characters with a small amount of information. It is possible. Regarding the PDL code, PostScript, CaPSL, and the like are currently known. Elements such as graphics formed from the PDL code are sequentially developed in the memory one by one, so that a newly drawn image is drawn on the upper side while erasing information of the old image. By doing so,
Where the newly drawn shape overlaps the previously drawn shape,
The newly drawn figure overwrites the previous figure.

[0003]

However, in the above-mentioned conventional example, data writing to a multi-valued full-color image memory, which takes a longer time than a binary image, is performed.
Depending on the location, the same pixel may be repeated twice, three times,..., And there is a disadvantage that information to be erased by overwriting may be developed over a long period of time.

Further, since the size of a figure is limited to one page, the size of a drawing destination memory is required for one page, and the size of one page of a multi-value full-color image is limited to a binary image. In comparison, a large memory space was required. For this reason, there is a disadvantage that the cost of the entire apparatus is increased.

The present invention has been made in view of the above-mentioned drawbacks of the conventional example, and has as its object to provide an image processing apparatus capable of shortening a drawing time by changing a drawing method.

Another object of the present invention is to provide an image processing apparatus which can reduce the memory by changing the drawing method and reduce the cost of the entire apparatus.

[0007]

[MEANS FOR SOLVING THE PROBLEMS] To achieve the above object
The image processing apparatus of the present invention has the following configuration.
That is, in an image processing apparatus including a forming unit that forms an image based on a code indicating a page description language and a storage unit that stores a binary image, an analysis unit that analyzes the code indicating the input page description language; A rearranging unit that rearranges the input page description language so that the drawing order based on the result analyzed by the analyzing unit is reversed; a storing unit that stores codes obtained by the rearranging unit; A binary image drawing means for drawing a binary image based on the stored code; and a binary image already written at a pixel position to be drawn during drawing by the binary image drawing means.
Determination means for determining dolphin not, by the determining means
Pixel position where it is determined that the binary image has already been written
Contains a multi-valued image based on the code stored in the storage means.
Is not drawn, and a binary image is determined by the determination means.
The determined pixel position and has not been written, and the multi-level image drawing means for drawing a multi-valued image based on the code stored in the storage unit, drawn by the multi-value image drawing unit
Output means for outputting the multi-valued image obtained.

[0008]

In the above configuration, the input page description language
Is analyzed, and drawing is performed based on the analysis result.
Arrange the input page description languages so that the order is reversed.
And store the rearranged codes. This stored
Draw a binary image based on the code, and
During the drawing of the value image, the binary image is already
Judge whether or not a binary image has already been written.
The pixel location that is determined to be
Do not draw multi-valued images based on
The pixel position where it is determined that no image has been written
Draws a multi-valued image based on the stored code,
Output a multi-valued image.

The registering means registers a color image with color information, the first forming means forms multi-valued color data based on the color information registered by the registering means, and the first compression storage means stores the first compressed storage means. Compressing the multi-valued color data formed by the forming means, storing the compressed data, and expanding the compressed data stored in the first compression storing means when the capacity of the registration means is insufficient, This expansion data is stored and the second
Forming means, after executing the decompression storage means, forms multi-valued color data based on the color information registered by the registration means,
The synthesizing unit synthesizes the multi-valued color data formed by the second forming unit with the decompressed data stored by the decompressing storage unit, and the second compression storage unit compresses the result obtained by the synthesizing unit, and compresses the compressed data. The storing and forming means forms a color image in accordance with the compressed data stored in the first compressed storing means or the second compressed storing means.

[0010]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. <First Embodiment> FIG. 1 is a block diagram showing an image processing system according to a first embodiment of the present invention. In the figure, 1 is an input buffer, 2 is a PDL code analysis unit, 3 is an intermediate buffer, 4 is a binary image forming unit, 5 is a binary image memory, 6 is a color image forming unit, 7 is a color image memory, 8
Is a printer engine, 9 is a CP that controls the entire system.
U and 10 are ROMs storing information such as programs for operating the CPU 9 in accordance with the flowchart of FIG.
Is a RAM used as a work area for various programs. The above configuration is used as the image processing system because the printer including the printer engine 8 and the printer engine 8
This means that the printer controller that does not have a printer can be set in any way. Of course, it goes without saying that the image processing system of FIG. 1 may be a printer.

FIG. 2 is a diagram for explaining a binary image according to the first embodiment, and FIG. 3 is a diagram for explaining a multi-valued color image according to the first embodiment.

A binary image is, as shown in FIG.
By using one bit to display one pixel on the value image memory 5, the value is indicated only by binary information of on and off. As shown in FIG. 3, a multi-valued color image is stored in a color image memory 7 having four memories of cyan (C), magenta (M), yellow (Y), and black (K).
Each one pixel has an 8-bit information amount and has 256 bits.
This is indicated by gradation density information. Even when the same area is drawn, the multi-valued color image draws four times the area of the binary image. Also, the amount of information for each pixel needs to be eight times. This makes the drawing time of the color image memory 7 longer. Therefore, in the present embodiment, the binary image memory 5 having a high drawing speed is used as a write determination flag for the color image memory 7 in order to eliminate unnecessary access to the color image memory 7 by double coating.

Next, FIG. 1 will be described in detail.

The input buffer 1 is a buffer for temporarily storing a PDL code. The PDL code includes font information for designating a character font, character information for designating a character to be printed, and the type and size of a graphic. There are graphic information to be specified, position information to specify a print position, color information to specify a color, and the like. The PDL code 50 is sent from the input buffer 1 to the PDL code analyzer 2. The PDL code analysis unit 2 adds print position information and color information to each print element, such as characters and figures. The output order of each element is adjusted so as to be opposite to the order at the time of drawing, and the PDL code 51 is created. The PDL code 51 in the intermediate buffer 3 is sent to the binary image forming section 4. In the binary image forming section 4, the PDL code 51 is developed to form a binary image, and the image is drawn in the binary image memory 5. If the pixel at the drawing destination is bit "0", the bit " 1 "is written, and the color image forming unit 6
Then, the coordinates of the writing destination and the color information are sent. Color information is 4
The color is designated by designating the density of each color ink. However, when the bit "1" is set on the binary image memory 5, since the corresponding portion on the color image memory 7 has already been written and the value is to be finally output, Nothing is sent to the color image forming section 6. The above is performed for each pixel of the drawing coordinates. When the coordinates and the color information are sent to the color image forming unit 6, the color image memory 7 stores the color information based on the color information in a memory corresponding to the coordinates indicating the same portion of each of cyan, magenta, yellow, and black. Calculate and write at 256 levels of density. As a result, four color images can be overlapped to form one color image. By repeating this, the figure drawn below is drawn without breaking the figure drawn before that. The full color image drawn in the color image memory 7 is output by the printer engine 8.

Next, the operation of this embodiment will be described.

FIG. 4 is a diagram showing an example of a general PDL code, FIG. 5 is a diagram for explaining a general multi-valued color image drawing method, and FIG. 6 is a drawing of a multi-valued color image according to the first embodiment. FIG. 7 is a flow chart for explaining the printing procedure according to the first embodiment.

First, in a general drawing method (FIG. 5), the PDL code of FIG. 4 is developed sequentially from the right and written directly to a multi-value memory (not shown). Initially, a rectangle is drawn with cyan (C), magenta (M), yellow (Y), and black (K) at respective densities based on color information (a), and then a circle is drawn (b) ), And finally draw the ABC of the character (c). At this time, where the circle and the rectangle overlap, the circle drawn later will be drawn without missing. A figure is drawn in this way.

On the other hand, in the drawing method of the present embodiment, the drawing order of the PDL code in FIG. 4 is reversed by the PDL code analysis unit 2, and the drawing is performed in the order of characters, circles, and squares. First, as shown in steps S1 to S3, "AB" is stored in the binary image memory 5 with a bit "1".
At this time, since the binary image memory 5 is initialized and all bits are "0", each time a bit "1" is written, the binary image memory 5 is stored in four memories of the multi-valued color image memory 7. (A) Drawing at each density After drawing the ABC, circles are similarly developed in the binary image memory 5 as shown in steps S4 to S6, with the bit "1" at the stage of (a). In the case where drawing is performed at a place where the described ABC is overlapped, control is performed so that drawing is not performed in each memory of the color image memory 7. In other words, a circle drawn in the color image memory 7 has a bit portion of ABC. Similarly, the rectangle shown in (c) is drawn by drawing a rectangle in which ABC and the bit portion of the circle have been omitted.

The data drawn in the color image memory 7 in this way is sent to the printer engine 8, and the printing process is performed (step S7).

As described above, according to the first embodiment, the drawing time becomes shorter as a figure having a larger overlapping portion is drawn.

In the above-described embodiment, only the case where a multi-valued full-color image is used is used. However, the present invention may be applied to an apparatus having a binary full-color image memory and a binary full-color printer.

Further, in the above-described embodiment, it is assumed that the PDL code to be input to the input buffer is in the drawing order of the conventional system. However, the drawing software for creating the PDL code in the reverse order of the drawing order is used. May be.

Further, in the above-mentioned embodiment, the color image is not shown in the drawing element, but the compressed color image is handled in the reverse order of drawing when drawing like graphics and characters. 2
On the value image memory, write a rectangle having an expanded area without writing a binary image, and write the expanded color image data into the color image memory only in the portion where 1 is not set. . <Second Embodiment> FIG. 8 is a block diagram showing an image processing system according to a second embodiment of the present invention. In the figure, 101 is an input buffer, 102 is a PDL code analysis unit, 103 is an image development unit, 104 is a page memory,
5 is a color map, 106 is a multi-valued color imaging unit, 10
7 is a multi-valued color buffer, 108 is a compression / expansion unit, 109
Is a color image compression memory, 110 is a printer engine,
111 is a CPU that controls the entire system, 112 is a CP
A ROM 113 stores information such as a program according to the flowchart of FIG. 9 for operating the U111, and a RAM 113 is used as a work area for various programs. The image processing system in this embodiment is also used for the same reason as in the first embodiment.

In this embodiment, by registering colors in the color map 105, colors can be represented by numbers. However,
"0" in 8 bits per pixel, "0" for all R, G and B
This indicates that only 255 colors can be registered to represent transparency. Color map 105 is full (FUL
Each time L), the image is compressed while being converted into a multi-valued color image, so that the multi-valued color buffer 107 becomes smaller.

Next, each circuit of FIG. 8 will be described in detail.

The input buffer 101 has a PDL code 15
This is a buffer that temporarily stores 1. PDL code 15
Reference numeral 1 denotes font information for specifying a character font, character information for specifying a character to be printed, type and size of a figure, graphic information to be specified, position information for specifying a printing position, color information for specifying a color, and the like. Including information. Hereinafter, a character, a figure, a position, or the like indicated by each piece of information is used as a drawing element.

The PDL code is sent from the input buffer 101 to the PDL code analyzer 102. The PDL code analysis unit 102 adds print position information and color information to each print element such as a character or a figure, arranges the drawing order of each element, and passes the intermediate code 151 to the image development unit 103. The image developing unit 103 analyzes the intermediate code 151 and develops image data on the page memory 104. The page memory 104 and the color map 105 are initialized to bit "0" before drawing a new page.

At the time of development, if the color of the graphic to be developed is not registered in the color map 105, the unregistered color is registered in the color map 105. An element is drawn by writing the number of the color to be drawn in the page memory 104. With this method, up to 255 colors can be drawn.
If the number of colors exceeds 255, the information in the page memory 104 is converted into a multi-valued color by the multi-valued color image forming unit 106 and developed into a multi-valued color buffer 107. When the size of 8 × 8 is expanded, the image data is compressed by the compression / expansion unit 108 using an ADCT (Adaptive Discrete Cosine Transform) method that is a color image compression method, and is stored in the color image compression memory 109.
The data stored in the page memory 104 for the second time or later is obtained by expanding the data previously stored in the color image compression memory 109 onto the multi-value color buffer 107 and then rendering it as a multi-value color image. The image synthesized in this way is immediately compressed to obtain a multi-valued color buffer 10.
7 can be small.

When the drawn image is printed out, the compressed image is output by expanding the compressed image in accordance with the output speed of the printer engine 110.

Next, the operation of this embodiment will be described.

FIG. 9 is a flowchart for explaining a printing procedure according to the second embodiment.

If the information sent from the input buffer 101 to the PDL code analysis unit 102 is a PDL code, it is analyzed, otherwise the system processing ends (steps S111, S112). After the analysis of the PDL code in step S112, if the color required for the element to be drawn is already registered in the color map 105 (step S113), the process proceeds to step S116.
The numbers registered in the page memory 104 are drawn,
The next PDL code is read. On the other hand, if not registered (step S113), step S114
In order to register the necessary color for the element to be drawn, the number of registered colors in the color map 105 after registration is checked. As a result, if the registration number falls within 255 colors, the necessary color is registered in the color map 105 (step S115), and the process proceeds to the above-described step S116. The page memory 104 has a color map 105
Only the numbers registered in are recorded.

On the other hand, if it is determined in step S114 that the number of registered colors in the color map 105 after registration exceeds 255 colors, a process of storing the image data in the page memory 104 in the multi-valued color image compression memory 109 is performed. Start.
Therefore, first, if the compressed data is already stored in the multi-valued color image compression memory 109, step S118 is performed.
In step S119, the compressed data is expanded to the multi-valued color buffer 107. In step S119, the data of the multi-valued color buffer 107 is expanded and compressed at the same time as the color image compression memory 1.
09. Further, in the color map 105 and the page memory 104, initialization is performed.
Proceed to reading the DL code. Step S117
If the storage of the compressed data is not confirmed, the process proceeds directly to step S119.

If it is determined in step S120 that there is no PDL code, the process proceeds to step S117 and thereafter, the image drawn in the page memory 104 is stored in the color image compression memory 109, and this processing ends. I do.

As described above, according to the second embodiment, the memory can be reduced by changing the drawing method.
The cost of the entire apparatus can be reduced.

In the above-described second embodiment, one pixel of the page memory is set to 8 bits. However, this may be any bit as long as the entire memory usage is smaller than when using a multi-valued full-color image memory. However, it is necessary to make the size of the memory of the color map correspond to the value.

In the above-described second embodiment, the image compression method is ADCT. However, the present invention is not limited to this. Any compression method for a multi-valued color image may be used.

In the above-described second embodiment, when a color is registered in the color map, if the color is different,
Although all are registered, when the color is close to a previously registered color, the number of elements to be written to the page memory may be increased by using the close color. As a result, the number of times of compression and decompression of an image can be reduced, so that deterioration of image quality can be reduced.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. Needless to say, the present invention can be applied to a case where the present invention is achieved by supplying a program to a system or an apparatus.

[0040]

As described above, according to the present invention, the rendering time of a multi-valued color image can be reduced.

Further, by changing the drawing method, the size of the memory can be reduced, and the cost of the entire apparatus can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an image processing system according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a binary image according to the first embodiment.

FIG. 3 is a diagram illustrating a multi-valued color image according to the first embodiment.

FIG. 4 is a diagram illustrating an example of a general PDL code.

FIG. 5 is a diagram illustrating a general multi-valued color image drawing method.

FIG. 6 is a diagram illustrating a method of drawing a multi-valued color image according to the first embodiment.

FIG. 7 is a flowchart illustrating a printing procedure according to the first embodiment.

FIG. 8 is a block diagram showing an image processing system according to a second embodiment of the present invention.

FIG. 9 is a flowchart illustrating a printing procedure according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 101 Input buffer 2, 102 PDL code analysis part 3 Intermediate buffer 4 Binary image formation part 5 Binary image memory 6 Color image formation part 7 Color image memory 8, 110 Printer engine 9, 111 CPU 10, 112 ROM 11, 113 RAM 50, 51 PDL code 103 Image developing unit 104 Page memory 105 Color map 106 Multi-value color image forming unit 107 Multi-value color buffer 108 Compression / expansion unit 109 Color image compression memory

Claims (3)

(57) [Claims] 1. An image processing apparatus comprising: a forming unit for forming an image based on a code indicating a page description language; and a storage unit for storing a binary image, an analysis for analyzing a code indicating the input page description language. Means, sorting means for sorting the input page description language so that the drawing order based on the result of analysis by the analysis means is reversed, storage means for storing codes obtained by the sorting means, A binary image drawing means for drawing a binary image based on the code stored in the storage means; and a pixel position to be drawn during drawing by the binary image drawing means.
Determining means for determining whether or not a binary image has already been written to the device; and determining that the binary image has already been written by the determining means .
The code stored in the storage means is stored in the determined pixel position.
Without rendering a multi-valued image based on the
Means has determined that a binary image has not been written
At the pixel position, there is provided a multi-valued image drawing means for drawing a multi-valued image based on the code stored in the storage means, and an output means for outputting a multi- valued image drawn by the multi-valued image drawing means. Characteristic image processing device. Wherein said binary image drawing means includes a binary image memory to be <br/> drawing destination of the binary image, the multi-value image drawing
Means for storing a multi-valued image in a color image memory
The output means is drawn in the color image memory.
The image processing apparatus according to claim 1, wherein the multi-valued image is output . 3. The image processing apparatus according to claim 1, wherein the rearranging unit rearranges the order of the graphic image and the character image in the order of the character image and the graphic image.