JP3377298B2 - Color image printing system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color image printing system for converting original color image data generated by a host device into printable color image data and outputting the same from a print output means.

[0002]

2. Description of the Related Art CAD data generated by a CAD system, image data read by an image scanner, etc. are a set of drawing commands for a plotter,
Since these are compressed raster data, it is necessary to convert the data format to a printable format when outputting them with a raster printer or the like. In particular, in the case of printing a color image, the color image data on the host computer is based on the three primary colors of RGB, and the image data output by the printer is CMYK ink colors. Image processing such as color correction is required. Further, when printing out a full-color image, gradation processing is required to obtain a pseudo full-color image.

Conventionally, in this type of image processing, the processing performed on the host side and the processing performed on the printer side have been clearly determined. For example, in a certain system, print output is performed for original color image data. Among the processing performed for this purpose, pixel image generation, color matching processing, and gradation processing are performed on the host side, and then the print data is transferred to the printer, and the CMYK processing is performed on the printer side and printed output. Is done. Also, in some systems, only the pixel image generation is performed on the host side in the processing for print output with respect to the original color image data, and then the print data is transferred to the printer for color matching on the printer side. Processing, gradation processing,
CMYK processing is performed and printed output.

[0004]

However, in the conventional color image printing system described above, the printer cannot perform its own processing until the data is sent to the receiving buffer. Further, the host device cannot perform the next work until all the created image data is loaded into the reception buffer. As described above, in the conventional system, it is easy to waste the next work of oneself depending on the progress of the processing of the other party, which is a problem in improving the processing speed.

The present invention has been made to solve the above problems, and an object thereof is to provide a color image printing system capable of reducing the waiting time of image processing and improving the processing speed. To do.

[0006]

SUMMARY OF THE INVENTION A color image printing system according to the present invention is for producing a host device for producing original color image data to be printed out, and for producing and outputting the original color image data produced by this host device. In the color image printing system including the image processing means for converting into the color image data for printing and the print output device for printing out the color image data for printing processed by the image processing means, the image processing means comprises: It comprises a first image processing means provided on the host device side and a second image processing means provided on the print output device side, and the first and second image processing means are:
At least a part of them has a common function, and the first
Image processing means executes its own processing according to the progress of the image processing in the second image processing means, and when transferring the data to the second image processing means, The information indicating whether or not the processing has been completed is added, and the second image processing means sequentially activates the unfinished processing based on the information added by the first image processing means. And

Further, the color image printing system according to the present invention includes a host device for generating original color image data to be printed out, and a printing color for printing out the original color image data generated by the host device. A color image printing system comprising: an image processing means for converting into image data; and a print output means for internally printing a color image data for printing processed by the image processing means The image processing means includes a first image processing means provided on the host device side and a second image processing means provided on the printer side.
Image processing means, the first and second image processing means have a common function in at least a part thereof, and the first image processing means is provided on the printer side for each predetermined data unit. Check the freeness of the buffer. If the buffer is low, the data unit is processed by itself. If the buffer has a predetermined amount of space, which process has been completed for the data unit? Is added to the buffer and transferred to the buffer, and the second image processing means sequentially activates unfinished processes based on the header information for each data unit stored in the buffer. And

[0008]

According to the present invention, the image processing means for converting the original color image data into printable color image data which can be printed out is provided on the host side and the printout means side so that at least a part of the processing overlaps. It is provided on both sides, and depending on the processing status of the image processing means on the print output means side, part of the image processing is shared and executed on the host side as well. However, the processing speed can be improved.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a functional block diagram showing the configuration of a color image printing system according to an embodiment of the present invention. This system is composed of a host computer 1 and a printer 2 which receives image data from the host computer 1 via, for example, a SCSI interface and performs print processing. The host computer 1 includes a color image data generation unit 11, a first image processing unit 12, and buffer transfer units 131, 132 and 133.
, 134, and are provided. The color image data generation unit 11 generates original color image data to be printed out. The original color image data includes CAD data created on the system, RGB raster data read and processed by a color image scanner, and the like. The first image processing unit 12 generates printing color image data that can be output by the printer 2 from the original color image data generated by the color image data generation unit 11. The first image processing unit 12 is
For example, it is realized by a printer driver of software, and as a plurality of unit processes, for example, a pixel image generation unit 21, a color matching unit 22, a gradation processing unit 23
And a CMYK converter 24.

The pixel image generation unit 21 bit map develops CAD data in the drawing command format, compressed raster data and the like on a memory (not shown) on the host computer 1 to generate a pixel image. The pixel image data is obtained by arranging the color information of each pixel of the image in order from the upper left to the lower right of the image. If one pixel is represented by 24 bits, it represents about 16.7 million kinds of colors. The color matching unit 22 corrects a difference between a numerical color expressed inside the computer and a color actually output by the printer, that is, a slight color shift caused by a characteristic difference between the two devices, and is prepared in advance. Replace the pixel color by referring to the created color matching table with the pixel image data.

The gradation processing unit 23 converts a pixel image expressed in full color into a pseudo full color image, and combines, for example, eight colors of white, cyan, magenta, yellow, black, red, green and blue. Reconstruct the pixel image so that it looks full color. Although various well-known methods can be used in the gradation processing unit 23, if the unit of data distributed to the host side and the printer side is a relatively large band data unit, the pattern dither method, An error diffusion method or the like can be used. When the data is distributed in units of one row, the pattern dither method that completes the processing in units of one row can be used. The CMYK converter 24
4 colors of cyan, magenta, yellow, and black that can output the color of each pixel obtained by the gradation processing unit 23 with a printer
Convert to one ink color. The converted data is output in the form of bitmap data.

A pixel image generation unit 21, a color matching unit 22, a gradation processing unit 23 and a CMYK conversion unit 24.
Output data of the buffer transfer units 131, 132, 1
It is output to 33 and 134, respectively. Buffer transfer unit 1
31 to 134 check the availability of the receiving buffer 31 provided on the printer 2 side. If the receiving buffer 31 has an available space, header information indicating up to which stage the processing is currently completed is displayed. The data is added to the beginning of the data and transferred to the reception buffer 31. If the receiving buffer 31 does not have a predetermined amount of free space, the data is transferred to the next unit processing unit of the first image data processing unit 12.

On the other hand, the printer 2 is provided with a header identifying section 32, a second image processing section 33, a bitmap memory 34, and a figure output processing section 35, in addition to the reception buffer 31 described above. There is. The second image processing unit 33 includes a color matching unit 41, a gradation processing unit 42 and a CM.
The YK converter 43 is provided. These are the color matching unit 2 provided in the first image processing unit 12.
2. It has the same function as the gradation processing unit 23 and the CMYK conversion unit 24. The header information identifying unit 32 determines from the header information transferred with the data from the host computer 1 side up to when the data has been processed, and based on the determination result, the data is color-matched by the color matching unit 41. The data is transferred to one of the gradation processing unit 42, the CMYK conversion unit 43, and the bitmap memory 34.

Next, the operation of the present system thus constructed will be described. Here, as an example, the image data to be processed is composed of m × n pixels as shown in FIG. 2, and four m × n / 4 pixel band data B1, B2, B3 obtained by dividing the image data into four. , B4 as one processing unit will be described. FIG. 3 is a flowchart showing processing in the first image processing unit 12 and the buffer transfer unit 13 of the host computer 1. The data provided from the color image data generation unit 11 is, for example, compressed raster data of 256 gradations per pixel, or a set of drawing commands that have not been raster-converted. This data is supplied to the pixel image generation unit 21 in units of band data and developed into RGB bitmap data (S1). Next, the buffer transfer unit 131 checks the vacant state of the printer buffer 31 (S2). If there is no vacant space, the RGB bitmap data is transferred to the color matching unit 22. If there is a space, "0" indicating that the process after the color matching process is unprocessed is written in the header information, and the data added with this is transferred to the printer 2 (S3).

When the data expanded into the RGB bitmap is supplied to the color matching section 22, color correction is performed here (S4). Next, the buffer transfer unit 132 confirms that the printer buffer 31 is free (S5). If there is no free space, the RGB correction bitmap data is transferred to the gradation processing unit 23. If there is a space, "1" is written in the header information, which indicates that gradation processing and below are not processed, and the data added with this is transferred to the printer 2 (S6).

When the color-corrected RGB bitmap data is supplied to the gradation processing unit 23, conversion processing into pseudo color data is executed (S7). Subsequently, the buffer transfer unit 133 confirms the empty state of the printer buffer 31 (S8). If there is no free space, the pseudo color data is transferred to the CMYK conversion unit 24. If there is a space, "2" indicating that the CMYK conversion has not been completed is written in the header information, and the data with this added is transferred to the printer 2 (S9).

When the RGB bitmap data converted into the pseudo color data is supplied to the CMYK converter 24,
Here, conversion processing of ink colors into CMYK bitmap data is executed (S10). Then, the buffer transfer unit 1
At 34, the empty state of the printer buffer 31 is confirmed (S11), and if there is no empty space, wait until there is an empty space (S13). If there is a space, "3" indicating that all image processing has been completed is written in the header information, and the data with this added is transferred to the printer 2 (S12).

On the other hand, on the printer side, the receiving buffer 3
The processing of FIG. 4 is started every time data is stored in 1. First, the header identification section 32 identifies the header information (S2
1). If the header information is “0”, the buffer 3
After reading data from 1 in units of one line, for example (S2
2), color matching processing (S23), gradation processing (S
24) and CMYK processing (S25) are sequentially executed. When the processing of all the rows of the transferred data is completed, the processing ends (S26), but in the middle of the processing, the above processing is repeated according to the header information (S27). When the header information is "1", "2", and "3", respectively, after data reading (S28, 29, 30), gradation processing (S2) is performed.
4) Subsequent processing, CMYK conversion (S25) and subsequent processing, data storage in the bitmap memory 34 (S31)
The respective processes of are executed.

According to the above processing, as shown in FIG.
First, the host computer 1 creates a pixel image of the band data B1, and the data is transferred to the printer 2 and subjected to image processing after color matching processing. In the meantime, the band data B2 is converted into a pixel image inside the host computer 1 and then sequentially subjected to color matching processing and gradation processing. When the gradation processing of the band data B2 is completed, the image processing of the band data B1 is completed and the reception buffer 31 is in an empty state, so the gradation processed band data B2 is transferred to the printer 2. . In the printer 2, for the band data B2, only the remaining CMYK conversion needs to be executed. Similarly, during execution of this CMYK conversion,
The host computer 1 generates a pixel image of the next band data B3. Since the receiving buffer 31 is in an empty state after the pixel image is generated, the band data B3 is transferred to the printer 2, and at the same time, the host computer 1 starts the processing of the next band data B4. Immediately after the image processing of the band data B3 is completed inside the printer 2, the image processing of the hand data B4 is also completed inside the host computer 1.
The data of the band data B4 is only stored in the bitmap memory 34 on the printer 2 side.

As described above, according to this system, the image processing is shared between the host computer 1 and the printer 2 according to the processing status of the two.
Since no waiting time occurs in any of the devices and parallel processing is possible, the processing can be executed extremely efficiently.

In the above embodiment, the processing on the side of the host computer 1 was executed in band data units. However, if this processing is performed in smaller units, for example, in units of one line, the waiting time on the printer side will be reduced. It is further shortened and the processing efficiency is improved. FIG. 6 is a flowchart showing a processing procedure in the host computer 1 for realizing such processing. In this process, the pixel image generation process (S41), the color matching process (S45), the gradation process (S49), and the CMYK conversion process (S53) are executed line by line, each time the process is completed. The vacancy of the buffer 31 is checked (S42, S46,
S50, S54). Since the processing is performed on a line-by-line basis, the time from the occurrence of the buffer vacancy to the data transfer becomes short. If the buffer has a free space, a code indicating which processing has been completed and a code indicating the size of the data are added as header information and the data is transferred (S4).
3, S47, S51, S55). If the buffer is full, until the processing of one band data is completed,
The same process is repeated (S44, S48, S52, S5
7).

[0022]

As described above, according to the present invention, the image processing means for converting the original color image data into the printable color image data capable of being printed out has at least a part of the processing overlapping. It is provided on both the host side and the print output means side. Depending on the processing status of the image processing means on the print output means side, part of the image processing is shared and executed on the host side as well. There is an effect that it can be improved.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration of a color image printing system according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining units processed by the system.

FIG. 3 is a flowchart showing processing on the host side in the same system.

FIG. 4 is a flowchart showing processing on the printer side in the system.

FIG. 5 is a time chart showing an actual processing procedure in the system.

FIG. 6 is a flowchart showing processing on the host side of the system according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Host computer, 2 ... Printer, 11 ... Color image generation part, 12 ... First image processing part, 131
... 134 ... Buffer transfer unit, 21 ... Pixel image generation unit, 22, 41 ... Color matching unit, 23, 42 ...
Gradation processing unit, 24, 43 ... CMYK conversion unit, 31 ... receiving buffer, 32 ... header identifying unit, 33 ... second image processing unit, 34 ... bitmap memory, 35 ... drawing processing unit.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H04N 1/46 H04N 1/46 Z (58) Fields investigated (Int.Cl. ⁷ , DB name) G06T 1/00 G06F 3 / 12 G06F 13/38 G06T 1/20 H04N 1/46 H04N 1/387

Claims (2)

(57) [Claims] 1. A host device for generating original color image data to be printed out, and image processing means for converting the original color image data generated by the host device into printing color image data for printout. In a color image printing system including a print output device that prints out the color image data for printing processed by the image processing means, the image processing means includes first image processing means provided on the host device side. And a second image processing means provided on the side of the print output device.
And the second image processing means has a function common to at least a part of them, and the first image processing means performs its own function in accordance with the progress of the image processing in the second image processing means. When the processing is executed and the data is transferred to the second image processing means, information indicating up to which processing is completed is added to the data, and the second image processing means is A color image printing system in which unfinished processing is sequentially activated based on the information added by the first image processing means. 2. A host device for generating original color image data to be printed out, and image processing means for converting the original color image data generated by the host device into printing color image data for printout. In a color image printing system having a buffer for receiving data therein, and a print output unit for printing out the color image data for printing processed by the image processing unit, the image processing unit is provided on the host device side. It comprises a first image processing means provided and a second image processing means provided on the printer side, and the first and second image processing means have a function common to at least a part of them. The first image processing means confirms the freeness of the buffer on the printer side for each predetermined data unit, When the buffer has little free space, the data unit is processed by itself, and when the buffer has a predetermined free space, the data unit is added with header information indicating which process has been completed, A color image printing system, wherein the second image processing means sequentially activates unfinished processing based on the header information for each data unit stored in the buffer.