JP4514168B2 - Image processing system and image processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform image processing with a quality appropriate for the characteristics of an image to be written. SOLUTION: This system for processing image by receiving a command for defining the attributes of individual elements constituting an image and generating a bit map image as an attribute map based on that command, comprises a unit for generating an attribute map information group of an image bring printed based on the attribute information of an element defined by the command. At least one attribute map in the attribute map information group is generated while reflecting the signal from an external image processing unit other than the inputted command and defines an image quality suitable for the image being printed.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image processing method and an image processing system for improving the quality of an output image when image data is digitally generated and printed out.
[0002]
[Prior art]
Conventionally, such a system as shown in FIG. 16 is known. This shows a general configuration of a system that uses a host computer 101 to create a page layout document such as DTP, a word processor, a graphic document, and the like, and outputs a hard copy by a laser beam printer, an inkjet printer, or the like. Reference numeral 102 denotes an application that runs on a host computer, and typical examples include word processing software such as Microsoft Word (R) and page layout software such as Adobe PageMaker (R). Digital documents created with these software are transferred to the printer driver 103 via an operating system (OS) of a computer (not shown).
[0003]
The digital document is usually represented as a set of command data representing figures, characters, etc. constituting one page, and these commands are sent to 103. A series of commands constituting the screen is expressed as a language system called PDL (page description language), and GDI (R) and PS (R) (postscript) are well known as typical examples of PDL. The printer driver 103 transfers the received PDL command to the rasterizer 105 in the raster image processor 104. Reference numeral 105 denotes a two-dimensional bitmap image for actual printer output of characters, graphics and the like expressed by the PDL command. Since a bitmap image is an image that fills a two-dimensional plane as a one-dimensional raster (line) repetition, 105 is called a rasterizer. The developed bitmap image is temporarily stored in the image memory 106.
[0004]
The document image 111 displayed on the host computer is sent as a PDL command string 112 to the rasterizer via the printer driver, and the rasterizer develops a two-dimensional bitmap image on the image memory as shown at 113. The developed image data is sent to the color printer 107. An image forming unit 108 of a well-known electrophotographic system or ink jet recording system is used for 107, and a visible image is formed on a sheet using these and printed out. Image data in the image memory is transferred in synchronization with a not-shown synchronization signal or clock signal necessary for operating the image forming unit, or a transfer request for a specific color component signal.
[0005]
[Problems to be solved by the invention]
In the conventional example described above, it is clear that various problems arise when the image forming unit used for output is considered.
[0006]
For example, in general, a color printer uses a four-color toner or ink of cyan (C), magenta (M), yellow (Y), and black (K) to form a color image on a print output. Image formation is performed based on the so-called subtractive color mixing principle. On the other hand, when a host computer application displays an image, it is common to use a color monitor. The color monitor uses three additive primary colors of red (R), green (G), and blue (B). Display the color. Accordingly, the colors of characters and graphics constituting the document, or the image obtained by reading out a photograph or the like with a scanner and the like are all expressed as colors in which R, G, and B are mixed at a certain ratio.
[0007]
In other words, the rasterizer defines PDL as R, G, B and converts the color information transferred from the host computer into C, M, Y, K by some means, then generates a bitmap image and sends it to the printer There is a need to. However, the method of converting RGB to CMYK is not uniquely determined, and the optimum conversion method differs depending on the graphic attributes defined in PDL. For example, referring to the example of FIG. 17, the portion 114 is a natural image read by a scanner or the like, 115 is an electronically generated graphic image such as a circle or rectangle, and 116 is a character (TEXT) image. have.
[0008]
If the 116 TEXT colors are defined as black with R = G = B = 0, the optimal CMYK signal for this is expressed as an 8-bit density signal, C = M = Y = 0, and K = 255. That is, it is preferable to reproduce black characters using only black toner among the four colors of toner of the printer. On the other hand, if the pixel value of a specific pixel of the natural image 114 is R = G = B = 0, if converted to C = M = Y = 0 and K = 255 as in the case of the character data, Since the portion with the highest density in the natural image is to be expressed only with black toner, the absolute density is insufficient.
[0009]
Therefore, in this case, it is preferable that the absolute density is increased by converting into values such as C = M = Y = 100 and K = 255. In order to solve such a problem, the rasterizer develops a bitmap image using RGB values without performing conversion to CMYK, and from among the RGB bitmap images sent on the image forming unit side. A method of detecting a character image region using a known image region separation method, and generating and outputting CMYK data by switching a conversion method from RGB to CMYK in the detected character image region and other regions. Is also considered.
[0010]
However, in this case, the image area separation method is not always capable of detecting 100% of the character area, and may be detected as a character area by mistake in the natural image area. There is a bug. As another example, there may be a case where the image forming unit can reproduce only binary dots. In this case, the rasterizer develops a multi-value bitmap image of Y, M, C, and K in an image memory. The image forming unit that receives the raster image is a well-known binarization method such as an error diffusion method or a dither process. The multi-valued image signal is converted into a binary image signal after processing, and then printed out.
[0011]
At this time, the optimum binarization method changes depending on the attribute of the image. In other words, graphics such as characters and figures are preferably binarized by reducing the dither matrix size and emphasizing resolution. For natural images such as photographs, it is better to increase the matrix size and emphasize tone reproducibility. preferable. Also in this case, a method of adaptively switching the dither matrix size by performing image area separation processing on the multi-valued bitmap image transferred from the image memory is possible, but the same problem as described above is prevented. It is not possible.
[0012]
[Means for Solving the Problems]
Accordingly, an object of the present invention is to provide an image processing system and an image processing method for executing image processing with appropriate quality for the characteristics of an image to be drawn.
[0013]
In order to solve the above problems and achieve the object, an image processing system and method according to the present invention are mainly characterized by the following configurations.
[0014]
  That is,An image processing system according to the present invention includes a host computer, a raster image processor, and an image processing unit.An image processing system,
  The host computer
  A dialog screen is displayed, and according to an instruction input via the dialog screen, the color bitmap is set as a color attribute, and when the level difference of the color information of each RGB color is equal to or less than a predetermined level, the color bitmap is set as A designation means for designating image quality;
  Application generated,Configure the imageEssentialElementaryContains information indicating that is a text object, graphic object, or bitmap object, and color information for each objectcommandOutput means for outputting
  The raster image processor
  Conversion means for converting the command output by the output means into two-dimensional bitmap data interpretable by an image forming unit;
Information indicating whether each pixel of the two-dimensional bitmap data converted by the conversion means is generated from the character object or the graphic object, or generated from the bitmap object; and the two-dimensional bitmap data Creation means for creating information indicating whether each pixel is color or black and white, and an attribute map that associates each pixel of the two-dimensional bitmap data with the designation of the designation means; ,
  The image processing unit
In accordance with the attribute map, the image processing means performs image processing for converting the two-dimensional bitmap data converted by the conversion means into image data that can be output by an image forming unit.It is characterized by that.
[0015]
  Also,An image processing method according to the present invention is executed by an image processing system having a host computer, a raster image processor, and an image processing unit.An image processing method comprising:
  The steps executed by the host computer include
  The designation unit displays a dialog screen, and according to an instruction input via the dialog screen, the color bitmap has a color attribute, and if the difference in the level of color information of each RGB color is equal to or less than a predetermined level, the monochrome attribute As a specification process to specify the image quality of the object,
  The output means is generated by the application,Configure the imageEssentialElementaryContains information indicating that is a text object, graphic object, or bitmap object, and color information for each objectcommandAn output process for outputting
  The steps executed by the raster image processor include:
  A converting step for converting the command output in the output step into two-dimensional bitmap data interpretable by an image forming unit;
Information indicating whether each pixel of the two-dimensional bitmap data converted in the conversion step is generated from the character object or the graphic object, or generated from the bitmap object; A creation step of creating an attribute map that associates each pixel of the bitmap data with color or black and white and each pixel of the two-dimensional bitmap data according to the designation in the designation step And having
  The steps executed by the image processing unit are:
The image processing means includes an image processing step for performing image processing for converting the two-dimensional bitmap data converted in the conversion step into image data output from the image forming unit according to the attribute map.It is characterized by that.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 is a block diagram that best represents an image processing system according to the present invention.
[0018]
10 is a host computer. Reference numeral 11 denotes an application such as a word processor, draw software, or graphic software used in the host computer. Reference numeral 12 denotes a printer driver that controls an interface with the printer when outputting characters, graphics, or bitmap images from the application to the printer. Reference numeral 13 denotes a raster image processor for developing the output through the printer driver into image data. In the image processor 13, an image memory for storing the rasterizer 14 and the image data 15 and an attribute map memory are stored. 16 is included.
[0019]
Reference numeral 20 denotes external processing means for adding advanced information to the attribute map, and the attribute map memory 16 is rewritten based on the result obtained in 20.
[0020]
Reference numeral 17 denotes an image processing unit for making the image data stored in the image memory into a higher quality image and making the image data output by the image forming unit 19 described later. Reference numeral 18 denotes a color printer. The printer 18 includes an image forming unit 19 for printing image data as electronic data on a medium such as paper. The image forming unit 19 is an electrophotographic unit or an inkjet unit, and obtains a final output result through the image forming unit 19.
[0021]
The attribute map will be described in detail later.
[0022]
In the present embodiment, the description will be made as the color printer 18, but it goes without saying that the present invention can be easily applied to a monochrome printer.
[0023]
Further, for easy understanding, the image memory 15 and the attribute map memory 16 are written in separate blocks, but the image data and the attribute map data are stored in a single storage medium so that they can be read out. Is also possible.
[0024]
A digital document created by an application is expressed by a command system called PDL as described in the conventional example, and the command is roughly composed of three objects. One is a character object, the second is a graphic object such as vector data such as a figure or a free curve, and the third is a Bitmap object such as a photograph or printed matter read by a scanner or image data.
[0025]
If an object is a character, it consists of data such as a character code to identify which character it is, a font that defines the character shape, size information that represents the size of the character, and color information that represents the color of the character. As it is, the information cannot be interpreted by the image forming unit. The printer driver 12 manages the interface with the printer, and plays a role such as synchronizing so that an appropriate image can be output by the image forming unit 19 which is the final stage, while the object such as characters, graphics, and Bitmap is given to the rasterizer 13. Send a command sequence representing. The rasterizer 14 converts the received command sequence into two-dimensional Bitmap data that can be properly interpreted by the image forming unit, and at the same time outputs an attribute map that is a feature of the present invention. The attribute map is a two-dimensional information by giving the attribute information of each pixel to each pixel. The attribute map memory 16 stores the two-dimensional image data, the attribute map, and the correspondence for each pixel. Store as possible.
[0026]
Reference numeral 20 denotes external processing means for making the attribute map more sophisticated information, and in this embodiment, it is character determination processing means.
[0027]
FIG. 4 is an example of an attribute map format. It has 1-bit information of only the 0th bit, and the 0th bit is a Bitmap flag. 1 indicates a pixel generated from a Bitmap object, and 0 indicates a pixel generated from a vector object, that is, a character or graphic image. When converting an object into 2D Bitmap data, the rasterizer determines for each pixel whether it was finally generated from a character, graphic, or natural image object, and corresponds to the 2D image data in the attribute map. Store it so that it can be attached.
[0028]
FIG. 5 is an example of attribute map information associated with each pixel. An image in which the number “1”, which is a character object, is superimposed on the bitmap object is shown. When converting to a two-dimensional bitmap, according to the format of the attribute map, 1 is output for each pixel generated by a Vector (character or graphic object) for each pixel, and 0 is output for a Bitmap object. Generate an attribute map like
[0029]
Here, it should be noted that the attribute map information is reversed from FIG. Depending on how to create the format, as shown in Fig. 4, it may be 1 for Bitmap, 0 for Vector (character or graphic), or 0 for Bitmap and 1 for Vector (character or graphic) as shown in Fig. 5. May be.
[0030]
The attribute map may be configured in any way as long as the attribute map is stored so as to be associated with each pixel. For example, as an attribute map plane as shown in FIG. 5, the image data may be stored in the image memory 15 and the attribute map information may be stored in the attribute map memory 16 or stored in the same storage medium. In this case, when an attribute map plane is added to each RGB plane as shown in FIG. 6A, or when RGB data is configured in one pixel as shown in FIG. You may embed in the form added to the RGB information of each pixel. Further, in order not to increase the amount of data, as shown in FIG. 6C, the attribute map information is embedded in the lower bits for each pixel on any one surface or a plurality of surfaces of the RGB planes. When RGB data is configured in one pixel as shown in FIG. 6D, one or a plurality of information of 8 bits each of RED, GREEN, and BLUE for each pixel An attribute map may be embedded in the lower bits of the color information.
[0031]
FIG. 6D shows an example in which an attribute map is embedded in the lower 3 bits of 8 bits of BLUE information.
[0032]
(Explanation of the part without corresponding figure)
The format interpreter 105 extracts the attribute map information embedded as described above, and associates the image data stored in the image memory 104 and the image data for each pixel according to the attribute map format. Based on the attribute map, the attribute of each pixel is determined, and the image processing unit 106 switches image processing to perform optimum image processing for each image attribute.
[0033]
For example, the use of attribute map information enables the following. Referring to the example of FIG. 17, the portion 114 has a different attribute such as a natural image read by a scanner, 115 an electronically generated graphic image such as a circle or rectangle, and 116 a character (TEXT) image. ing.
[0034]
Here, there may be a case where the image forming unit can reproduce only binary dots. In this case, the rasterizer develops a multi-value bitmap image of Y, M, C, and K in an image memory. The image forming unit that receives the raster image is a well-known binarization method such as an error diffusion method or a dither process. The multi-valued image signal is converted into a binary image signal after processing, and then printed out. At this time, the optimum binarization method also changes depending on the attribute of the image. In other words, graphics such as characters and figures are preferably binarized by reducing the dither matrix size and emphasizing resolution. For natural images such as photographs, it is better to increase the matrix size and emphasize tone reproducibility. preferable.
[0035]
According to the format of FIG. 4 using the attribute map information of the present invention, the character image 116 and the graphic image 115 are 0 in the 0th bit of the attribute map, and the 114 natural image (Bitmap) is the attribute map. Since the 0th bit is a 1 pixel, it is possible to easily separate a natural image, a character image, and a graphic image for each pixel.
[0036]
However, among the Bitmap objects that are assigned to the attribute map as natural images, images that are read from the original using a reading device such as an image scanner can read character images in addition to so-called natural images such as photographs and printed materials. There may be. In this case, according to the attribute map described so far, all the information is uniformly stored as a natural image, and binarization processing with an emphasis on gradation reproducibility is performed on the entire surface, so that the Bitmap object The character image read in is an image with low resolution and difficult to read.
[0037]
FIG. 12 is a diagram assuming a case where a character image is included in an image read from a document using a reading device such as an image scanner. It is assumed that the number “2” is read as data of the bitmap object in the image of FIG. Since the image in FIG. 12 is a read image, the 0th bit of the attribute map is created assuming that all Bitmap attributes are as shown in FIG. In the present embodiment, the character image area is detected by using character determination means that is an external process. The character determination means is a means for determining whether each pixel is a character portion or other than a character portion. Various known methods have been proposed and are not related to the essence of the present invention. Then, detailed explanation is omitted.
[0038]
In the character image area detected by the character determination unit, the 0th bit of the attribute map is rewritten as 0 by replacing the 0th bit of the attribute map with 1. FIG. 14 shows attribute map data rewritten by the above method. It can be seen that the pixels constituting the number “2” have been rewritten from 1 to 0.
[0039]
By doing so, the Bitmap object does not have the Bitmap attribute uniformly, and the character image data included in the Bitmap object can have a character attribute or a graphic Vector attribute. In this way, when the rasterizer is expanded, not only an attribute map is created, but also one or more attribute map data is created or rewritten according to the result of external processing, thereby enabling a more advanced image. A system that can realize quality can be constructed.
[0040]
The dither matrix shown in FIG. 2 is used when the 0th bit of the attribute map is 0. Further, the dither matrix shown in FIG. 3 is used for the attribute map in which the 0th bit is 1. Here, the multi-value data used in this embodiment is 8 bits, 0 to 255 level, and when the value of the multi-value data of each pixel is larger than the threshold value of each cell of the dither matrix in FIGS. Then, if it is less than the threshold value of each cell, the dot is turned off.
[0041]
FIG. 2 is a dither matrix having a size of 3 × 3. If one pixel is assumed to be 600 dpi, it can be reproduced with a resolution of 200 dpi, and the number of gradations is 10. Therefore, although the number of gradations is small, high-resolution image reproduction is possible. FIG. 3 shows a dither matrix having a size of 8 × 8. If one pixel is assumed to be 600 dpi, the dither matrix is 75 dpi, and the number of gradations is 65 gradations. Although the resolution is low, the number of gradations is large, and natural images can be reproduced with high quality compared to FIG. In this way, by switching the dither matrix for each pixel by the attribute map, it is possible to reproduce characters and graphics with high resolution while maintaining gradation in natural images, and provide high-quality images Is possible.
[0042]
In addition, even when characters exist in a natural image, the attribute map can be rewritten by external processing, that is, character determination means as described above, so that the resolution can be expressed higher, and a higher quality image can be obtained. Can be reproduced.
[0043]
In the present embodiment, the present invention is realized by rewriting an already created attribute map. However, new attribute map information can be added as shown in FIG. In FIG. 11, if bit0 is 1, it indicates a bitmap (natural image), if it is 0, it indicates a vector (character or graphic), and if bit1 is 1, it indicates a character in the bitmap (natural image).
[0044]
In order to explain the present embodiment, the character determination means is written as the external processing means, but other processing means may be used as long as the external processing can obtain information other than the attribute assigned at the time of expansion. Needless to say.
[0045]
(Second Embodiment)
FIG. 7A is an example of a document created by an application, and there are a character object, a graphic object, and a natural image object. Reference numeral 7-a denotes a natural image object, which is created with a color bitmap, but is an image containing black and white characters. Reference numeral 7-b denotes a natural image object, which is created by a color bitmap and is not an image to be output in black and white.
[0046]
In the color bitmap, when black and white information is used, R, G, and B are represented at approximately the same level, and are converted to C, M, and Y data at approximately the same level when printed. Is done. Further, RGB data is often converted into CMYK four-color data at the time of printout. K is black and is a signal generated by a process called UCR. When generating a black image using characters, line images, etc., if CMY is combined to generate black data, the position where the image is written out by the printer will be misaligned and the color may appear blurred, or the color balance will be poor. It may become reddish black or bluish black, and the image quality may be significantly impaired. In addition, there is an advantage that printing in black suppresses toner consumption compared to printing in three colors of CMY. However, there is a demerit that if the ratio of printing in black on a natural image increases, the image will look poor with low saturation.
[0047]
Therefore, in order to output natural images with high saturation, color conversion processing that consists of three colors of CMY without using black is used to reproduce black or black with high quality such as characters and graphics. It is possible to obtain a higher quality image by using a color conversion process that increases the amount of black in order to reproduce the image so as to reduce the influence of the image. This is a process that is possible using a conventional attribute map.
[0048]
However, 7-a is assigned an attribute such as a color and a natural image when the conventional attribute map creation method is employed. In the case of a natural image, as described above, it is generated in three colors of CMY so that it does not become a poor-looking image with reduced saturation, so black and white characters are written in spite of black and white characters being written. The quality of the image is poor (redish), and the color blurs due to the color shift and the image quality deteriorates. In order to prevent this, in this embodiment, an image processing system is configured as shown in FIG.
[0049]
10 is a host computer. Reference numeral 11 denotes an application such as a word processor, draw software, or graphic software used in the host computer. Reference numeral 12 denotes a printer driver that controls an interface with the printer when outputting characters, graphics, or bitmap images from the application to the printer. A raster image processor 13 expands the output through the printer driver into image data. In the image processor 13, an image memory for storing 14 rasterizers and 15 image data, and a 16 attribute map memory are stored. including.
[0050]
Reference numeral 21 denotes attribute map designating means for designating an attribute map desired by the operator. The 16 attribute map memory is rewritten based on the result instructed in 21. Reference numeral 17 denotes an image processing unit for converting the image data stored in the image memory into a higher quality image and image data that can be output by a 19-image forming unit described later. Reference numeral 18 denotes a color printer. Includes 19 image forming units for printing image data, which is electronic data, on a medium such as paper. The 19 image forming unit is an electrophotographic unit or an inkjet unit, and a final output result is obtained through the 19 image forming unit.
[0051]
FIG. 15 shows the format of the attribute map used in this embodiment.
[0052]
If bit0 is 0, it indicates the Vector attribute (character, graphic object), if it is 1, it indicates the Bitmap attribute (Bitmap object (natural image)), and if bit1 is 0, it indicates the monochrome image attribute.
[0053]
The operator designates using the attribute map designation means 21.
[0054]
FIG. 7B is an example of an interactive screen of a program installed on the host computer in order to realize the attribute map specifying means 21. In FIG. 7B, a portion corresponding to 7-a in FIG. 7A is designated and selected using a pointing device such as a mouse, and 7-a is highlighted. A pop-up dialog is displayed, and the attribute map is designated as a Bitmap attribute and a color attribute.
[0055]
FIG. 9 shows only the dialog shown in FIG. 7B. By designating bit1 to black and white with a mouse or the like and clicking OK, the information in the attribute map 16 in FIG. 8 is rewritten, so that 7-a in FIG. 7A is bit0 is 1 and bit1 is 0, that is, the Bitmap attribute. In addition, the monochrome attribute can be set. If nothing is specified for 7-b and the Bitmap attribute and the color attribute are left as they are, 7-a is black and white, which is replaced with a black signal, and high-quality black without color misregistration. 7-b can be output as a high-quality image with high saturation as a color bitmap.
[0056]
The designation from the operator can also be realized by designating to the printer driver as follows.
[0057]
An example for designating a method for creating an attribute map from the printer driver is shown in FIG.
[0058]
FIG. 10 is a diagram in which a dialog for specifying an attribute map creation method in the printer driver is activated. If the above items are specified, all color bitmaps are generated as CMY three colors without UCR as color attributes. If the middle item is designated, it is generated so as to be replaced with a black attribute when the difference between the RGB colors is 10 levels or less. If the lower item is designated, processing is performed using a predetermined UCR as a default mode. The operator can obtain desired image quality by designating any of these from the printer driver.
[0059]
As described above, by providing the means for the operator to specify the attribute map, it is possible to switch the image processing method with a higher degree of freedom and to provide a high-quality image.
[0060]
[Other Embodiments]
Note that the present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, and a printer), and a device (for example, a copying machine and a facsimile device) including a single device. You may apply to.
[0061]
Another object of the present invention is to supply a storage medium (or recording medium) in which a program code of software that realizes the functions of the above-described embodiments is recorded to a system or apparatus, and the computer (or CPU or CPU) of the system or apparatus. Needless to say, this can also be achieved by the MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention. Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. It goes without saying that a case where the function of the above-described embodiment is realized by performing part or all of the actual processing and the processing is included.
[0062]
Furthermore, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the function is determined based on the instruction of the program code. It goes without saying that the CPU or the like provided in the expansion card or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.
[0063]
When the present invention is applied to the above-described storage medium, the program code corresponding to the above description is stored in the storage medium.
[0064]
【The invention's effect】
As described above, according to the present invention, an external image processing signal other than the command is reflected in the bitmap image as the attribute map based on the command for defining the attribute of each element constituting the image, It is possible to generate an attribute map that defines image quality suitable for an image to be printed and to perform image processing.
[Brief description of the drawings]
FIG. 1 is a block diagram of an image processing system that best represents the present invention.
FIG. 2 is an example of a dither matrix used in the description of the first embodiment.
FIG. 3 is an example of a dither matrix used in the description of the first embodiment.
FIG. 4 is an example of an attribute map format used in the description of the first embodiment.
FIG. 5 is an example of an attribute map used for explaining the first embodiment.
FIG. 6 is an example of an attribute map storage method when image data and attribute map information are stored in the same storage medium.
FIG. 7A is a diagram of a document created by an application for explaining the second embodiment, and FIG. 7B is a diagram for explaining a method for specifying an attribute map in the second embodiment. It is a figure for doing.
FIG. 8 is a block diagram of an image processing system that best represents the second embodiment.
FIG. 9 is a diagram for explaining a method for specifying an attribute map in the second embodiment;
FIG. 10 is a diagram illustrating a method for designating an attribute map from a printer driver in the second embodiment.
FIG. 11 is a diagram illustrating an example in which information is added to the attribute map using an external signal in the first embodiment.
FIG. 12 is a view showing a read image used for explaining the first embodiment.
13 is a diagram showing the attribute map of FIG. 12. FIG.
FIG. 14 is a diagram showing an attribute map after rewriting the attribute map of FIG. 12 due to the effect of the first embodiment.
FIG. 15 is a format of an attribute map used in the present embodiment.
FIG. 16 is a diagram for explaining a conventional technique.
FIG. 17 is a diagram for explaining a conventional technique.
[Explanation of symbols]
10 Host computer
11 Application
12 Printer driver
13 Raster image processor
14 Raster Laser
15 Image memory
16 Attribute map memory
17 Image processing section
19 Image forming unit

Claims (2)

And a host computer, an image processing system comprising a raster image processor, an image processing unit, a
The host computer
A dialog screen is displayed, and according to an instruction input via the dialog screen, the color bitmap is set as a color attribute, and when the level difference of the color information of each RGB color is equal to or less than a predetermined level, the color bitmap is set as A designation means for designating image quality;
Yes application generates, and information indicating that elements that make up an image is a character object or graphic object or bitmap objects, and color information for each object, and an output means for outputting a command including the And
The raster image processor
Conversion means for converting the command output by the output means into two-dimensional bitmap data interpretable by an image forming unit;
Information indicating whether each pixel of the two-dimensional bitmap data converted by the conversion means is generated from the character object or the graphic object, or generated from the bitmap object; and the two-dimensional bitmap data Creation means for creating information indicating whether each pixel is color or black and white, and an attribute map that associates each pixel of the two-dimensional bitmap data with the designation of the designation means; ,
The image processing unit
An image processing system comprising image processing means for performing image processing for converting the two-dimensional bitmap data converted by the conversion means into image data that can be output by an image forming unit in accordance with the attribute map. . An image processing method executed by an image processing system having a host computer, a raster image processor, and an image processing unit ,
The steps executed by the host computer include
The designation unit displays a dialog screen, and according to an instruction input via the dialog screen, the color bitmap has a color attribute, and if the difference in the level of color information of each RGB color is equal to or less than a predetermined level, the monochrome attribute As a specification process to specify the image quality of the object,
Output means, is generated by the application, and outputs information indicating that elements that make up an image is a character object or graphic object or bitmap objects, and color information for each object, the command including an output And having a process
The steps executed by the raster image processor include:
A converting step for converting the command output in the output step into two-dimensional bitmap data interpretable by an image forming unit;
Information indicating whether each pixel of the two-dimensional bitmap data converted in the conversion step is generated from the character object or the graphic object, or generated from the bitmap object; A creation step of creating an attribute map that associates each pixel of the bitmap data with color or black and white and each pixel of the two-dimensional bitmap data according to the designation in the designation step And having
The steps executed by the image processing unit are:
The image processing means includes an image processing step for performing image processing for converting the two-dimensional bitmap data converted in the conversion step into image data output from an image forming unit according to the attribute map. Image processing method.

Images