JP2002207327A - Image forming system and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain, in image forming devices connected to a net work, a uniform image output in which calibration is performed even when an image is input from any one of the devices and even when an image is output by any one of the image forming devices. SOLUTION: The image forming system has an information processor (1) and image forming devices (3), each of which forms an image by interchanging information with the information processor (1). Each image forming device (3) has a formation unit (7) for forming an image based upon an input image, an image density detection unit (8) for detecting the density of the output image formed by the formation unit, and a control unit (5) for performing calibration in order to equalize the input image density with the output image density based upon instructing information received from the information processor (1).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming system for performing image calibration on a plurality of image forming apparatuses connected to a network, and an image forming method related to a calibration process.

[0002]

2. Description of the Related Art Various methods have been proposed as image calibration methods for an image forming apparatus, but all methods are calibration methods using a single apparatus.
There is no one that performs calibration so that the output densities of a plurality of image forming apparatuses connected to a network are equal and manages them with a host computer.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to output an image from any of a plurality of image forming apparatuses connected to a network, and to output an image from any of the image forming apparatuses. Even so, it is necessary to obtain a uniform image output.

[0004]

In order to achieve the above object, an image forming system, an image forming apparatus and a method according to the present invention are mainly characterized by the following constitution.

In other words, an image forming system for transmitting and receiving image information between devices connected to a network and performing calibration for making the characteristics of an image uniform is a method in which reference information generated by one device is used by another device. Receiving, forming means for forming an image in accordance with the received reference information, detecting means for detecting the density of the formed image, and, based on the detection of the detecting means, the reference information and the formed image And control means for calibrating the forming means for equalizing image density.

In the above image forming system, the one device receives the density information of the image measured by the other device, compares the received density information with the reference information, and obtains an error due to the comparison. If the value exceeds the allowable range, a unit for generating calibration information for canceling the error, and a unit for transferring the generated calibration information to the other device, the control unit includes: The calibration of the forming unit is performed based on the performed calibration information.

In the above image forming system, means for reading image information by the other device, receiving the read image by the one device, storing the received image data and the received image data in the one device Compared with the reference image,
When an error due to the comparison exceeds an allowable range, a unit that generates calibration information for canceling the error, and a unit that transfers the generated calibration information to the another device, The means performs calibration of the reading means based on the transferred calibration information.

In the above-described image forming system, the control unit performs a calibration of the density of the image information detected by the detection unit based on the transferred calibration information.

Alternatively, in an image forming method for performing calibration for making the characteristics of an image uniform, a reference information generated by one device is received by another device, and an image is formed in accordance with the received reference information. A forming step, a detecting step of detecting the density of the formed image, and a calibration of the forming step for equalizing the image density of the reference information and the formed image based on the detection of the detecting step. And a control step of performing the following.

In the above image forming method, the one device receives density information of an image measured by the other device, compares the received density information with the reference information,
When an error due to the comparison exceeds an allowable range, a step of generating calibration information for canceling the error, and a step of transferring the generated calibration information to the other device, comprising: The step is characterized in that the calibration of the forming step is performed based on the transferred calibration information.

In the above-described image forming method, a step of reading image information by the other device, receiving the read image by the one device, and storing the received image data and the received image data in the one device Comparing the generated reference image, if the error due to the comparison exceeds the allowable range, generating calibration information for canceling the error, and the generated calibration information to the other device Transferring the data, wherein the control step performs calibration in the reading step based on the transferred calibration information.

In the above image forming method, the control step performs a calibration of the density of the image information detected in the detection step based on the transferred calibration information.

In the above image forming apparatus, the one device is a host computer, and the other device is an image forming device connected to the host computer via a network.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming system, an image forming apparatus, and an image forming method according to the present invention will be described with reference to the drawings.

[First Embodiment] FIG. 1 is a schematic view showing a configuration example of an image forming system according to the present invention. Reference numeral 1 denotes a host computer, and reference numeral 2 denotes an external storage device connected to the host computer, which stores a reference image described below, a correction result obtained by performing a calibration, and the like.
Reference numeral 3 denotes an image forming apparatus. The image forming apparatus 3 further includes: an image reading unit 4; a control unit 5;
(I / F), and 7 image forming units. Reference numeral 8 denotes an image density detection unit that is provided in a recording medium discharge unit of the image forming unit 7 and detects image density on a medium, and 9 denotes a network cable. Further, ten client PCs are also connected to the network cable 9.

The image forming apparatus 3 is connected to a network 9
Above, multiple units are connected.

In the above configuration, the operation of the image forming system will be described in detail.

(1) Copy Function The original to be copied is placed on the image reading unit 4 and "copy mode" is selected by operating means (not shown).
By operating various settings such as the number of copies, a copy operation is performed, and a copy image is output to the image forming unit 7. These operations are controlled by the control unit 5.

(2) Printer Function When printing a document or an image file created in the client PC 10, the user designates the image forming apparatus 3 as an output destination and gives a print instruction. The image data is converted and output to the control unit 5 of the image forming apparatus 3 via the network cable 9, the host computer 1, and the I / F unit 6. The control unit 5 interprets the image data, visualizes the image data by the image forming unit 7, and outputs the image to a recording medium.

(3) Scanner function This is a function for taking in an image on a medium into the client PC 10 as electronic information. The original to be read is placed on the image reading unit 4 and "scanner mode" is selected by operating means (not shown). And the read resolution and output P
The scanner operation is started by making various settings such as the address of C. The image information read by the image reading unit 4 is compressed in a data amount by the control unit 5, converted into a protocol corresponding to a network by an I / F (interface) 6, and connected to the network cable 9 and the host computer 1. Via the client P
Sent to C10.

(4) Transmission Function In this mode, the image read by the image reading unit 4 of the image forming apparatus 3 is output by the image forming unit 7 of another image forming apparatus 3.

First, a document to be read is placed on the image reading unit 4, and a "transmission mode" is selected by operating means (not shown), and various settings such as a reading resolution and an address of the image forming apparatus 3 to be output are made. To start the image reading operation. The image information read by the image reading unit 4 is compressed in a data amount by the control unit 5, converted into a protocol corresponding to a network by an I / F (interface) 6, and connected to the network cable 9 and the host computer 1. Via the I / F (interface) of a desired (another) image forming apparatus 3
6 and transmitted to the control unit 5. The transmitted image information is expanded by the control unit 5, visualized by the image forming unit 7, and output to a recording medium as an image.

Next, the calibration method according to the present invention will be described in detail.

FIG. 2 is an example of a reference image pattern according to the present embodiment, which is a pattern in which the density of an image is changed stepwise. (A) is monochrome for monochrome, and (b) is color for Y (yellow), M (magenta), C (cyan) and K (black) in a stepwise manner.

The first calibration method for the image forming unit will be described with reference to the flowchart of FIG.

First, the number of times N for performing calibration is set (S301), an image forming apparatus 3 to be calibrated is selected, and reference image information is transmitted from the host computer 1 to the image forming apparatus 3 (S302). .
The image forming unit 7 of the image forming apparatus 3 forms a reference image on a recording medium based on the transmitted reference image information (S303). The image density is measured (S304). The measurement result of the concentration is stored in the host computer 1
And summed up (S305), and compared with the reference image signal (S306).

A comparison judgment processing unit (not shown) of the host computer 1 makes a comparison judgment, and if the difference between the two is within a predetermined error range, the measurement is terminated. If not within the error range, the process proceeds to the next step (S30).
7), a calibration unit (not shown) generates calibration information for correcting the image forming parameters of the image forming unit 7 so as to cancel the difference between the reference density information and the measured value.

This calibration information generally corrects the output γ (gamma) value of the image forming means 7 (S307). Next, the number of measurements N is reduced by 1 (S30).
8) It is checked whether N is not 0 (S309). If not, the process returns to step S302 to perform calibration. If 0 in S309, the set number of measurements has been completed, and thus the calibration is completed. The result of the calibration is transferred to the image forming apparatus 3, and the control unit 5 corrects the image forming parameters of the image forming unit 7 based on the result of the calibration.

When the image forming unit 7 is of a single color, calibration is performed using FIG. 2A as a reference image pattern.

In the case of full color (Y, M, C, K), all the colors may be output at once as shown in FIG. 2B, but the pattern of FIG. The reading may be performed by one image density detecting unit 8. In this case, the flow shown in FIG. 3 is performed for each color.

By the processing according to the flowchart of FIG. 3, the calibration of the image forming unit 7 can be executed.

Next, a second calibration method for the image input unit will be described with reference to the flowchart of FIG. First, the number of times N for performing the calibration is set (S401), and the reference image is placed on the image reading unit 4 of the image forming apparatus 3 for performing the calibration.
The image is read (S402).

The read image data is sent to the host computer 1 and tabulated (S403), and compared with a reference image signal stored in the external storage device 2 of the host computer 1 in advance (S404). If it is equal to or less than the reference value, it is determined that no correction is necessary, and the calibration ends. This comparison judgment is performed by a comparison judgment processing unit (not shown) of the host computer 1, and when the difference between the read image data and the reference image signal is equal to or larger than the reference value, the calibration unit (not shown) reads the image reading unit 4. Calibration information for correcting parameters is generated (S4).
05). This information is sent to the image forming apparatus 3 side, and the control unit 5 corrects the reading parameters of the image reading unit 4 according to the calibration information.

Next, the number of measurements N is reduced by one (S40).
6) It is checked whether N is not 0 (S407). If it is not 0, the process returns to step S402 and the calibration is performed again. If it is 0 in S407, the set number of measurements has been completed, and the calibration ends. When the image reading unit 4 is a single color, calibration is performed using FIG. 2A as a reference image pattern.

In the case of full color (Y, M, C, K), all colors may be output at once as shown in FIG. 2B, but the pattern of FIG. The reading may be performed by one image density detecting unit 8. In this case, the flow shown in FIG. 4 is performed for each color.

The calibration of the image reading unit 4 can be executed by the processing according to the flowchart of FIG.

Next, a third operation for the image density detecting unit will be described.
Will be described with reference to the flowchart of FIG.

First, after the first and second calibrations are performed, the number N of times of performing the calibration is set (S501). Is transmitted (S502). The image forming unit 7 of the image forming apparatus 3 forms a reference image on a recording medium based on the above-described reference image information and outputs the reference image (S503). The output recording medium is placed on the image reading unit 4 and an image is read (S504). The read image data is sent to the host computer 1 and totalized (S505) and compared with the reference image information (S506). If the difference is equal to or smaller than the reference value, it is determined that no correction is necessary, and calibration is performed. Ends.

This comparison judgment is performed by a comparison judgment processing unit (not shown) of the host computer 1. When the difference between the read image data and the reference image information is equal to or larger than the reference value, the first calibration method performs density detection. It is determined that it is necessary to correct the measurement value of the image density detection unit 8 that performed the above, and a calibration unit (not shown) generates calibration information for correcting the measurement parameter of the density detection unit 8 (S50).
7). This information is sent to the image forming apparatus 3 side, and the control unit 5 corrects the measurement parameters of the density detection unit 8 according to the calibration information.

Next, the number of measurements N is reduced by 1 (S508),
It is checked whether N is not 0 (S509). If it is not 0, the process returns to step S502 and the calibration is performed again. If it is 0 in S509, the set number of measurements has been completed, and the calibration is completed.

The calibration of the image density detecting unit 8 can be executed by the processing according to the flowchart of FIG.

As described above, according to the present embodiment, in any of a plurality of image forming apparatuses connected to a network, an image can be input from any apparatus, and an image can be output from any image forming apparatus. Even in this case, it is possible to obtain a uniform image output after calibration.

[Second Embodiment] In the first embodiment, information serving as a reference image is stored in the host computer 1 side.
The reference image information has been transmitted from the host computer 1 to each of the plurality of image forming apparatuses 3 to be calibrated. The image forming apparatus 3 forms an image based on the transmitted image information, reads the image, detects the density of the formed image, sends this information to the host computer 1, and the host computer 1 totals the data. Required calibration information was calculated.

On the other hand, each image forming apparatus 3 connected to the network may include a unit for generating a reference image in each image forming apparatus 3. The measured value of the image density detecting unit 8 when a reference image is formed and output in the image forming apparatus 3 and the value obtained by reading the formed image from the image reading unit 4 are stored in a memory (not shown) in advance. If the error is equal to or greater than the reference value, calibration data is generated.

For the generation of the calibration data, the flowcharts shown in FIGS. 3 to 5 can be applied as they are. Based on the reference image generated inside the image forming apparatus 3, the necessity of calibration of the image forming unit 7, the image reading unit 4, and the image density detecting unit 8 is determined, and the control unit 5 corrects those parameters. Even if it does, the same effect can be obtained.

[0046]

[Other Embodiments] Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copying machine) Machine, facsimile machine, etc.).

Further, an object of the present invention is to supply a storage medium (or a recording medium) in which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and a computer (a computer) of the system or the apparatus. Alternatively, it is needless to say that the present invention can also be achieved by a CPU or an MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. Also,
When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also the operating system (OS) running on the computer based on the instructions of the program code.
It goes without saying that a case where the functions of the above-described embodiments are implemented by performing some or all of the actual processing, and the processing performs the functions of the above-described embodiments.

Further, 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 program code is read based on the instruction of the program code. Needless to say, the CPU included in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium includes the storage medium described above (shown in FIGS. 3 to 5).
The program code corresponding to the flowchart is stored.

[0050]

As described above, according to the present invention,
In a plurality of image forming apparatuses connected to a network, even if an image is input from any apparatus or an image is output from any image forming apparatus, a uniform image output with calibration is obtained. be able to.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an image forming system according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a reference image according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating a calibration process of the image forming unit according to the embodiment of the present invention.

FIG. 4 is a flowchart illustrating a calibration process of the image reading unit according to the embodiment of the present invention.

FIG. 5 is a flowchart illustrating a calibration process of the image density detection unit according to the embodiment of the present invention.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H04N 1/407 H04N 1/40 101E F-term (reference) 2C061 AP01 AR01 KK25 KK32 KK35 2H027 DA09 DB01 DE02 EA18 EA20 EB01 EB04 EC07 EJ13 EJ15 ZA07 5B057 BA25 CA01 CA02 CA08 CB01 CB02 CB08 CE11 CH11 DB05 DB06 DB09 DC22 5C062 AA05 AA14 AA35 AB17 AB22 AB38 AB42 AC02 AC04 AC22 AC38 AC61 AE01 AF00 BA00 5C077 LL01 LL12 LL19 MM27 MP08 PP33 PP20

Claims (9)

[Claims] An image forming system for transmitting and receiving image information between devices connected to a network and performing calibration for making characteristics of an image uniform, wherein reference information generated by one device is converted to another device. Forming means for receiving an apparatus and forming an image in accordance with the received reference information; detecting means for detecting the density of the formed image; and detecting the reference information and the formed image based on the detection of the detecting means. Control means for calibrating the forming means so as to make the image densities equal to each other. 2. The apparatus according to claim 1, wherein the density information of the image measured by the another device is received by the one device, the received density information is compared with the reference information, and an error due to the comparison exceeds an allowable range. In such a case, there is provided: means for generating calibration information for canceling the error; and means for transferring the generated calibration information to the another device. 2. The image forming system according to claim 1, wherein calibration of the forming unit is performed based on the following. 3. A means for reading image information by said another device, receiving said read image by said one device, said received image data and a reference image stored in said one device. By comparing, if the error due to the comparison exceeds the allowable range, means for generating calibration information for canceling the error, and means for transferring the generated calibration information to the other device, The image forming system according to claim 1, wherein the control unit performs calibration of the reading unit based on the transferred calibration information. 4. The image forming system according to claim 1, wherein the control unit calibrates the density of the image information detected by the detection unit based on the transferred calibration information. 5. An image forming method for performing calibration for making characteristics of an image uniform, wherein reference information generated by one device is received by another device, and an image is formed in accordance with the received reference information. A forming step of forming, a detecting step of detecting the density of the formed image, and a detecting step of detecting the density of the formed image. And a control step of performing calibration. 6. The one device receives density information of an image measured by the another device, compares the received density information with the reference information, and an error due to the comparison exceeds an allowable range. In the case, a step of generating calibration information for canceling the error, and a step of transferring the generated calibration information to the other device, wherein the control step includes the step of transmitting the transferred calibration information. 6. The image forming method according to claim 5, wherein the calibration of the forming step is performed based on the following. 7. A step of reading image information by the other device, receiving the read image by the one device, and receiving the received image data and a reference image stored in the one device. By comparing, if the error due to the comparison exceeds the allowable range, a step of generating calibration information to cancel the error, and a step of transferring the generated calibration information to the other device, 6. The image forming method according to claim 5, wherein the control step performs the calibration in the reading step based on the transferred calibration information. 8. The image forming method according to claim 5, wherein the control step performs a calibration of the density of the image information detected in the detection step based on the transferred calibration information. 9. The image forming apparatus according to claim 1, wherein the one device is a host computer, and the other device is an image forming apparatus connected to the host computer via a network. system.