JP2003270880A - Image forming apparatus and method for setting image formation condition for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To set an appropriate image formation condition based on image data while intensively gathering principal image processing functions on an image processing board. <P>SOLUTION: In an electrophotographic image forming apparatus, the image data are obtained (S5) by analyzing a URL designated for printing (S2), and the image processing of the image data is set/performed on the basis of the data format of the obtained image data, the image forming condition of the image forming means is changed (S10 and S12), and then the image is formed by using developer on the basis of the image data processed by the image processing means (S11). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and an image forming condition setting method for the image forming apparatus, and more particularly to setting image forming conditions in an image forming apparatus for forming an image according to an electrophotographic method.

[0002]

2. Description of the Related Art In recent years, computers around the world have been linked mainly to the Internet, and various information is frequently searched and browsed using this computer.
As a typical method, a computer equipped with dedicated software for browsing information (hereinafter referred to as a browser) is connected to a server linked to a WWW (World Wide Web) via a network, and information on the WWW server is connected. From that computer to HTTP (Hyper Text Transfer Pr
otocol) is commonly referred to.

Further, in such a browser, the information on the browsed WWW server can be fetched and stored in a computer. Therefore, when necessary, the data stored in the computer is output to an image output device having a print function and printed to print various information on the WWW server and save it as a recording medium. It is being appreciated.

As such an image output device, a laser beam printer for forming an image according to an electrophotographic system or an inkjet printer for recording an image according to an inkjet system is generally used. In such a printer, image processing is performed on image data transmitted from a host device such as a connected computer,
Conversion to image data suitable for the printer is performed.

However, in the conventional printer device,
Since fixed image processing is always performed regardless of the type and content of image data, the following problems occur.

Gradation is emphasized in image data such as photographs, and resolution is emphasized in image data such as illustrations. However, since the same image processing is performed on all image data, the level of image data such as photographs is higher. The tonality may be impaired, or the resolution of image data such as an illustration may be impaired.

Since only a fixed gamma conversion process is performed, it is difficult to output an optimum tint corresponding to each image data. Similarly, since only the same undercolor processing is performed, it is difficult to output with an optimum color tone.

In order to solve such a problem, Japanese Unexamined Patent Publication No. 20
In Japanese Patent Application Laid-Open No. 00-207164, in an image forming apparatus that forms an image based on image data acquired from a network, an image in which gradation is required or an image in which resolution is required is determined based on an extension. It is disclosed to perform control so as to execute image processing according to the type of data.

Further, as an image output device, an image forming device such as an electrophotographic digital copying machine for converting a document image into image data by a reading device and obtaining a print image is increasingly used. Such an image forming apparatus is configured to transfer the image data transmitted from the computer to the image forming apparatus via an external device.

The external device accesses the network to acquire image data, expands the acquired image file into a raster image, and performs image processing to obtain an appropriate print image. Although the scale of hardware including circuits has been large, in recent years, the integration of hardware circuits has progressed, and there is also a configuration in which such an external device is built in the image forming apparatus.

Also in the printer device as a peripheral device of the computer as described above, recently, various image processing boards are selectively mounted according to the user's request,
It is required that the product specifications satisfy both the cost and the function desired by the user. That is, a part or all of the image processing circuit is required to be replaceable.

As described above, the image output device is required to be designed so that the structure of the image processing circuit can be made flexible. On the other hand, image processing methods have become more sophisticated, and various image processings have been proposed according to characteristics of image data such as various original images and characters. A configuration has also been proposed in which appropriate image processing is performed automatically or in response to a user's instruction. In this case, it is difficult to distinguish between the processing performed by the image processing circuit and the engine control on the printer engine side. Is coming.

For example, in an image forming apparatus having a function of predicting a toner (developer) consumption amount according to image data and controlling toner density, an image such as gamma conversion which is closely related to printer control. The printer engine is in charge of processing. That is, as a part of controlling the image forming means of the image forming apparatus, the printer engine mainly performs image processing according to the engine characteristic to correct the engine characteristic, and the printer engine receives the image data. Then, the image data integration process is performed, the toner consumption amount is predicted from the integration result, and the toner supply to the developing device is controlled.

Further, a toner patch image is formed on the photosensitive drum, the toner density in the developing device is measured, and the toner replenishment control is highly accurate based on the integrated result of the image data and the measured toner density information in the developing device. An image forming apparatus designed to perform the above is also devised.

On the contrary, in constructing an advanced and large-scale image processing circuit, the printer engine side of the image forming apparatus does not have a main image processing function, and the image processing board performs the main image processing. By doing so, an attempt has been made to provide the printer engine itself at low cost.

[0016]

As described above, when the configuration of the image processing circuit of the image forming apparatus is reviewed, the configuration of the image processing circuit is made flexible and various image processing functions are provided. It is understood that it is preferable to handle the information necessary for controlling the printer engine on the image processing board side rather than on the printer engine side.

However, in the conventional image forming apparatus as described above, the necessary information is generally handled only on the printer engine side regarding the toner replenishment control which is closely related to the printer characteristics.

Therefore, it is difficult to integrate the main image processing functions on the image processing board when performing various image processing.

Further, when the image forming conditions in the electrophotographic process such as charging, exposure, latent image, development, transfer, fixing, etc. are determined, the image forming conditions are appropriately set according to the characteristics of the image so that the image quality is It is known that this can be further improved.

However, in the current image forming apparatus,
It is hard to say that the process conditions for imaging are well optimized.

Specifically, in order to optimize the image forming conditions according to the type of image, it is necessary to set the image to be printed by either the user or the image forming apparatus. In this case, in an apparatus in which the user sets the image forming condition, the user's operation during printing becomes complicated and the operability deteriorates. Further, if the user forgets the setting or makes an incorrect setting, the optimum image formation will not be performed.

On the other hand, in an apparatus in which the image forming condition is automatically set on the image forming apparatus side, the image processing section performs an extraction process for extracting the characteristics of the image data to be printed, and the extracted image characteristics are extracted. Generally, it is configured to determine the type of image and set the image forming condition in the apparatus to the optimum condition. In this case, it is necessary to perform the feature extraction processing of the image data before actually printing, so it takes time to set the image forming conditions, and the time to actually start the printing operation becomes long. , The throughput will decrease.

The present invention has been made in view of the above situation, and even when an image forming board having a flexible structure capable of performing various image processing is used in an image forming apparatus, An object of the present invention is to provide an image forming apparatus and an image forming condition setting method for the image forming apparatus, which can set an appropriate image forming condition based on the image forming apparatus.

[0024]

In order to achieve the above object, an image forming apparatus as an aspect of the present invention is an image forming apparatus for forming an image according to an electrophotographic system, and a storage means for storing image data. An image processing unit that executes image processing on the image data stored in the storage unit; and an image forming unit that forms an image using a developer based on the image data processed by the image processing unit. The image processing means includes feature information notifying means for notifying the image forming means of characteristic information related to the image forming conditions of the image forming means based on the image data, The image forming means changes the image forming condition according to the characteristic information notified by the characteristic information notifying means.

That is, according to the present invention, in the image forming apparatus for forming an image according to the electrophotographic method, the image data is stored in the storage means, and the image processing means performs the image processing on the image data stored in the storage means. Along with running
Based on the image data, the image forming means is notified of characteristic information related to the image forming conditions of the image forming means, and the image forming means
The image forming condition is changed according to the notified characteristic information, and an image is formed using a developer based on the image data processed by the image processing means.

By doing so, the main image processing functions can be integrated in the image processing board as the image processing means, and an image processing board having a flexible structure capable of performing various image processing is used in the image forming apparatus. Even in this case, an appropriate image forming condition can be set based on the image data, and an image printing operation suitable for the type of image to be printed can be performed.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION First, image processing performed in the embodiments described below will be briefly described.

For example, currently on the Internet,
GIF and JPEG as image file formats
Etc. are commonly used. Of these, the GIF file format is a file format in which an image is compressed by lossless compression and saved, and the number of colors that can be displayed is 25.
Limited to 6 colors. Therefore, the GIF file format is often used for image data that does not require a large number of colors, such as illustrations and drawings.

Further, the JPEG file format is a file format which is compressed and stored by irreversible compression, and it is possible to display a very large number of colors such that the number of colors that can be displayed is about 16.77 million. For this reason, this JPEG file format is often used mainly for image data of natural images such as data obtained by digitizing photographs.

On the other hand, in printing an image by an electrophotographic method or the like, when the resolution of the image to be printed is increased, the waveform of an analog signal used as a pattern signal by pulse width modulation (PWM) or the like becomes an ideal triangular wave. This makes it difficult to print with ideal gradation.

Therefore, in the present embodiment, image data for which resolution is important is printed at high resolution, and image data for which color gradation is emphasized is printed at low resolution.

Further, image data such as illustrations and drawings,
Since image enhancement processing or smoothing processing settings are often different from those of image data such as photographs and natural images, in the present embodiment, image enhancement or smoothing settings can be set according to the format of each image data. .

In addition, when the RGB type image data is printed by the electrophotographic type printer, the image data expressed in RGB is C (cyan), M (magenta),
It is necessary to convert the density values of Y (yellow) and K (black) and send the converted image data to the printer. In this case, in a gray-color image printed using CMY toner, the gray color becomes a tinge gray, so it is better to print the gray portion only with black (K) toner. There are cases. On the contrary, when the gray portion is printed with only the black toner, and in the case of a gradation image in which the color changes smoothly from gray to another color, the reproduced gradation property of the gradation portion is deteriorated. Therefore, in such an electrophotographic printer, CMY toner and K
It is general to form an image by combining the above toner with an appropriate ratio. The ratio of CMY and K in this case is the Under Color Removal
l; UCR). In this embodiment, it is possible to set the under color removal according to the format of each image data.

Also, the area of one pixel is not variable, as in a binary printer, or it is limited to a very limited amount.
In the case of a printer that cannot change the pixel area, it is possible to print a gradation image by changing the number of colored pixels per unit area or the combination of these colored pixels. is there. Such an image representation method is called an area gradation method. According to this method, original image data is processed by a dither process or an error diffusion method, so that an image composed of only printable colors in a printer is obtained. It can be converted into data and printed. Even in such area gradation processing, by applying the most suitable conversion processing depending on the case of printing image data such as a photograph and the case of printing image data such as an illustration, the format of each image data can be changed. The area gradation processing can be set accordingly.

[First Embodiment] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

In the first embodiment, the HTTP protocol is used to send a command to a server that holds desired image data instructed by the user using the operation unit, and the server sends the command. An image forming apparatus that acquires image data stored in the server and forms an image in response to a reply will be described as an example.

FIG. 1 is a block diagram showing the arrangement of the image forming apparatus 1 of this embodiment, and here shows the state in which the image forming apparatus 1 is connected to the network 32.

In FIG. 1, reference numeral 2 denotes an image memory, which stores, for example, image data from the original image reading unit 201 or image data input via the network 32 via the network interface 3.
Hold. The network interface 3 controls communication via the network 32 with other devices connected to the network 32. An image processing circuit 4 performs various image processes on the image data stored in the image memory 2 and outputs the processed image data to the printer 5. The printer 5 functions as an image forming unit that inputs image data from the image processing circuit 4 and forms an image on a recording medium such as paper.

An operation unit 6 is used by the user to specify a place (a server or the like) where image data desired to be printed using the printer 5 is held. A server 7 is connected to the network 32 and holds various image data. Reference numeral 30 denotes a system bus through which data is transmitted and received between the CPU 101, which controls the overall operation of the image forming apparatus 1 of the present embodiment, and each unit. A video bus 31 is used to transmit the image data generated by the image processing circuit 4 to the printer 5. The network 32 is a communication path for connecting the image forming apparatus 1 and the server 7 to each other and for transmitting and receiving various data between these apparatuses. 102 is a memory,
The program executed by the CPU 101 and the CPU 1
The CPU 2 of the printer 5, which is also used as a work area for temporarily storing various data and the like during the operation of 01.
02 transmits and receives data to and from the CPU 101,
The CPU 202 performs a series of printer engine process controls such as paper transport control of the printer 5, toner image formation and toner replenishment operations, and transfer and fixing processes on paper.

When the original image is read, the copy key of the operation unit 6 is depressed to read the reading unit 2.
The image data read by 01 is read into the image memory 2, and the image data subjected to the predetermined image processing by the image processing unit 4 is sent to the printer 5 to form an image on a recording medium.

Here, the HTTP protocol will be described. The HTTP protocol is used to transfer data described in HTML (Hyper Text Markup Language), image data, etc., TC
It is a service on the P / IP protocol. This is usually
It is used in a system in which a client computer that issues a data transfer request and a server that holds data are connected by a network.

On the client computer, the HTT
The P client is operated, and in this HTTP client, the user determines the position of the data on the server.
It is input by an instruction format called a URL for designating a position where data is held. This makes HT
The TP client issues an information transfer request to the server in response to the input.

Further, the HTTP protocol includes a GET command which is a command for requesting data and a HEAD command which is a command for requesting related information regarding the data, and the data to be acquired is obtained by this HEAD command. It is a general practice to determine what kind of data it is in advance, then acquire that data by a GET command, and perform processing based on the acquired data.

The related information that can be acquired by this HEAD command includes the format information of the data together with the information such as the size and update date and time of the data.
The format information of this data is called "Content-type". According to this, for example, an extension such as "text / html" for data described in HTML, "image / GIF" for GIF image data, and "image / JPEG" for JPEG image data is added. Therefore, it is possible to determine what kind of data it is from this extension.

Now, for example, the host name of the server 7 is "ho
st.co.jp ”, if the position of the data to be acquired on that server is“ /pub/image.GIF ”, then“ http: //
By inputting the URL "host.co.jp/pub/image.GIF", the HTTP client first sends "/pub/image.GIF" to the server "host.co.jp".
HEAD command is issued.

The server 7 which has received this message, "/ pub / ima
ge.GIF ”data format information from the HE
It is sent to the HTTP client that issued the HEAD command as a reply to the AD command.

HT receiving the reply of this HEAD command
The TP client then issues a GET command for "/pub/image.GIF" to that server "host.co.jp".

Server 7 receiving this GET command
Is the HTT that issued the GET command in response to the data of "/pub/image.GIF".
Send to P client.

In this way, H which receives the reply of the GET command
The TTP client receives the format information “/pub/image.GI” received in response to the HEAD command.
F "data can be received and thus the received data can be processed.

In this way, the HTTP client
Based on the URL input from the operation unit 6, the specified data stored in the specified server 7 can be acquired together with the related information of the data. The flow of this processing will be described later with reference to the flowchart of FIG.

Next, the configuration of the image processing circuit 4 of this embodiment will be described. FIG. 2 is a block diagram showing the configuration of the image processing circuit 4 of this embodiment.

In the figure, reference numeral 8 denotes a DMA data transfer circuit, which controls the DMA transfer of image data from the image memory 2 to the image processing circuit 4. A LOG conversion circuit 9 converts RGB image data into CMY image data. A UCR circuit 10 performs UCR processing on CMY image data to generate CMYK image data 40. 11 is a PWM (pulse width modulation) circuit,
The laser drive signal 42 for controlling the lighting of the laser is generated from the CMYK image data.

Reference numeral 33 is an R data signal which means the red component data of the image data, 34 is a G data signal which means the green component data of the image data, and 35 is a B data signal which means the blue component data of the image data. , 36 are C data signals that mean the data of the cyan color component of the image data, 3
7 is M which means the data of the magenta color component of the image data
A data signal, 38 is a Y data signal which means the data of the yellow component of the image data, and 39 is a color selection signal for selecting the color for forming an image. Reference numeral 40 is a data signal selected from the CMYK data, 41 is a clock signal which is a reference synchronization signal for performing PWM processing, and 42 is a laser drive signal which controls the lighting of the laser.

The DMA data transfer circuit 8 is the system bus 3
0, and is controlled by the CPU 101 that controls the entire image forming apparatus 1 via the system bus 30. Under the control of the DMA data transfer circuit 8, when the image data held in the image memory 2 is transferred to the image processing circuit 4 by DMA transfer, first, the CPU 101
The DMA data transfer circuit 8 to the R, G, B
The address of the image memory 2 holding each image data and the data size for DMA transfer are set. After that, the DMA data transfer circuit 8 sequentially reads the R, G, and B data from the addresses designated by the DMA in the image memory 2 in synchronization with the operation of the printer 5.
The read data is output to the LOG conversion circuit 9 as an R data signal 33, a G data signal 34, and a B data signal 35. The RGB data is output to the LOG conversion circuit 9 in synchronization with three R, G, and B data. That is, the R, G, B data of each pixel of the image data are simultaneously output.

The R input to the LOG conversion circuit 9 in this way
Data signal 33, G data signal 34 and B data signal 3
5, the C data signal 36, the M data signal 37, and the Y data signal 38 are generated and output by the LOG operation. At this stage, the brightness data of the R, G, B data is converted into the density data of the C, M, Y data.

The C data signal 36, the M data signal 37 and the Y data signal 38 output from the LOG conversion circuit 9 are input to the UCR circuit 10. The UCR circuit 10 extracts the black component, which is the common part, from the C, M, and Y data and outputs it. The extraction of the black component is performed by determining the color having the minimum value of each data of C, M, and Y for each pixel and integrating the minimum value and a preset coefficient to obtain the data for the black toner. By determining the value of the K data to be obtained and subtracting the value of the K data from each of the C, M, and Y data, the value of each of the C ', M', and Y'data actually used for image formation It is realized by calculating

For example, when the coefficient for generating the data for black toner is 80% and C = 20, M = 90, and Y = 100, the minimum value is "20", Image data such as C ′: 4 (C−K) M ′: 74 (M−K) Y ′: 84 (Y−K) K: 16 (20 × 80% = 16) is generated.

Further, the UCR circuit 10 has a color selection signal signal 3
9 has been input, which means that the printer 5 has C, M, Y,
This is a signal necessary for adopting an image forming method of sequentially forming an image of K for each color, and which image data of C ', Y', M ', K when forming images of C, M, Y, K respectively. Is a signal for selecting whether to output.

In response to the input from the color selection signal signal 39, any one of the data signal 40 of C ', Y', M ', and K.
Is output as.

The data signal 40 output from the UCR circuit 10 is pulse width modulated in the PWM circuit 11 by the clock signal 41 which is a triangular wave. By this pulse width modulation, the data signal 40 input as, for example, 8-bit data is synchronized with the clock signal 41 and converted into a pulse wave having a pulse width corresponding to the value of the data signal 40. Is modulated. Further, in the PWM circuit 11, the input clock signal 41 is divided into two, for example, and PWM is performed at a frequency of 1/2 of the clock signal 41.
It is also possible to set to do.

By the color selection signal 39, C ', Y',
In response to the output of either the image data signal 40 of M ′ or K, the image data signal is data-corrected by a look-up table (hereinafter referred to as LUT) 302 and then sent to an integrator 301 for correction. Later image data is accumulator 30
1 is added up. The integrator 301 performs integration corresponding to each toner color, and the CPU 101 reads out the integration result,
It is stored in the memory 102. The CPU 101 reads out the accumulated result stored for each toner color from the memory 102,
Immediately as the toner consumption prediction data, C of the printer 5 is used.
Notify the PU 202.

The LUT 302 is composed of a random access memory rewritable by the CPU 101, and stores correction data for correcting image data according to printer characteristics for each toner color. For example, an image in which resolution is important is PWM-modulated at the cycle of the clock signal 41, but an image in which importance is attached to gradation reproducibility is PWM-modulated at a frequency half that of the clock signal 41. Even if there is, there is a slight difference in the toner consumption amount. Therefore, correction data that allows the correct toner consumption amount to be integrated is stored in the LUT 302, and which PWM is used.
The contents of the LUT 302 are rewritten depending on whether to print in the modulation mode. Alternatively, both correction data are stored, and the LUT is changed according to the PWM modulation mode.
CP so that the correction data referenced in 302 is switched
The upper address of the LUT 302 may be controlled by the U 101.

Next, the configuration of the printer 5 of this embodiment will be described. FIG. 3 is a block diagram showing the configuration of the printer 5 of this embodiment.

In the figure, reference numeral 12 is a semiconductor laser, which outputs a laser beam according to an input signal. A polygon mirror 13 has a regular hexagonal side surface that is mirror-finished and rotates according to the driving of the polygon motor 14. 15
Is a photosensitive drum, a latent image is formed by laser light,
A toner image is formed by electrostatically attracting the toner of the developing device to the latent image. 16 is a revolver, C, M,
Each of the Y and K toner cartridges is held and rotated according to the color to be developed. 17 is a C (cyan) toner cartridge, 18 is an M (magenta) toner cartridge,
19 is a Y (yellow) toner cartridge, 20 is K
A (black) toner cartridge. Each toner cartridge is composed of a toner bottle containing toner and a developing device containing a two-component developer composed of a magnetic carrier and toner. In the development process step for each toner color, the sleeve of the developing device rotates and the electrostatic latent image is developed with the toner from the developer on the sleeve, and a predetermined amount of toner is replenished from the toner bottle into the developing device. Thus, the developer toner concentration of the developing device in the toner cartridge is kept substantially constant.

Reference numeral 21 is a transfer drum for adsorbing a sheet,
The toner on the photosensitive drum 15 is transferred onto the paper. Reference numeral 22 is a fixing drum for fixing the toner onto the paper, 23 is a paper feed cassette for holding the paper and feeding the paper at the time of image formation, 42 is a laser drive signal, 43 is a laser beam emitted from the semiconductor laser 12, and 44 is a laser beam. Is a paper transport path.

The printer 5 is a printer which forms an image by an electrophotographic method, and forms an image on a sheet with four color toners of C (cyan), M (magenta), Y (yellow) and K (black). To form. When forming an image, first, the sheets stacked in the sheet feeding cassette 23 are fed, and the sheets are conveyed through the sheet conveying path 44,
It is attracted to the transfer drum 21 and sticks to the surface of the transfer drum 21. The transfer drum 21 rotates at a constant speed, and the paper also moves according to the rotation of the transfer drum 21.

On the other hand, when the printer 5 prints, the laser drive signal 42 is supplied from the image processing circuit 4. The supplied laser drive signal 42 is PWM
The data signal is any one of C, M, Y, and K PWMed by the circuit 11, and the data signal of C is first input. When this data signal is ON, the laser light source of the laser 12 emits light and the laser beam 43 is output. The laser beam 43 thus output is the polygon mirror 13.
Is irradiated. The polygon mirror 13 is rotated by the rotational driving of the polygon motor 14, and the laser beam 43 is scanned from one end of the photosensitive drum 15 to the other by this rotation. This one scan becomes one scan line in image formation. The scanning of the laser light causes the photosensitive drum 15 to move.
A latent image is formed on it. This latent image is a latent image having electrical characteristics that a portion irradiated with laser light has a high electric potential and a portion that does not have a low electric potential.

The latent image thus formed on the photosensitive drum 15 is first formed in a portion where the C toner developing sleeve in the C toner cartridge 17 previously arranged in a portion where the revolver 16 and the photosensitive drum 15 are in contact with the photosensitive drum 15. , In contact with the negatively charged cyan toner stored in the developer coated on the sleeve. This cyan toner is attracted and developed only by the portion of the photosensitive drum irradiated with the laser beam by an electric attraction force. Then, the portion of the photosensitive drum 15 on which the toner is adsorbed moves to the portion in contact with the transfer drum 21 due to the rotation of the photosensitive drum 15. At the portion where the transfer drum 21 and the photosensitive drum 15 are in contact with each other, the toner attracted to the photosensitive drum 15 is transferred onto the sheet attracted to the transfer drum 21.

Next, the revolver 16 is rotated 1/4 so that the M toner cartridge 18 contacts the photosensitive drum 15, and the M data signal is input as the laser drive signal 42, and C
The magenta toner image is transferred onto the sheet in the same manner as in the development described in 1. In the same manner, development with Y and K toners is also performed, and toner images of C, M, Y, and K colors are transferred onto the sheet adsorbed on the transfer drum 21.

After that, the sheet is separated from the transfer drum 21 and passes between the two fixing devices 22 through the sheet conveying path 44. At this time, the fixing device 22 heats and pressurizes,
The toner transferred onto the paper is fixed on the paper and is discharged to the outside of the printer 5. Printing is executed by the above operation.

Since the toner in the developing device is consumed when the printing operation is performed by the printer 5 as described above, particularly in the two-component developing system including the toner and the magnetic carrier, the toner density is maintained at an appropriate level. As described above, it is necessary to perform toner replenishment control for replenishing the appropriately consumed toner into the developing device.

Therefore, the CPU 1
01 to the CPU 202 of the printer 5 based on the toner consumption amount prediction information for each toner color
02, C, M, Y, K toner cartridge 1
The toner is controlled to be replenished from the toner bottles 7, 18, 19, and 20 into the developing devices for the respective toner colors.

In the present embodiment, the printer engine configuration having the transfer drum 21 has been described. However, instead of the transfer drum, four color toner images are sequentially superposed on an intermediate transfer body such as an intermediate transfer drum or an intermediate transfer belt. After that, an engine form may be used in which batch transfer is performed on the conveyed paper.

Next, the processing operation of the image forming apparatus 1 of this embodiment will be described with reference to the flowchart of FIG. FIG. 4 shows the CPU 101 of the image forming apparatus of this embodiment.
5 is a flowchart showing a control process executed by the above, and a program for executing this process is stored in the memory 102.

The image forming apparatus 1 has an operating section 6, which is provided with buttons and a display and is used by the user to operate the image forming apparatus 1. In the operation unit 6, the user designates the place where the data to be printed exists by the URL. The image forming apparatus 1 waits for input until this input is made (step S
1). When the URL is input in step S1, the process proceeds to step S2, the structure of the input URL is analyzed, and the address of the server holding the desired data and the position of the data to be acquired in the server are determined. Identify. Here, it is assumed that the server 7 has data to be acquired.

Then, in step S3, a HEAD command for the data to be acquired is issued to the server 7. This HEAD command is
It is transmitted to the server 7 via the interface 3 and the network 32.

Server 7 which received this HEAD command
HEAD based on the information about the specified data.
Format information for the command is generated and transmitted to the image forming apparatus 1 via the network 32 and the network interface 3. This results in step S4
Then, when the format information from the server 7 is received, the process proceeds to step S5, and the "Content-type" information is extracted from the format information from the server 7 and stored.

Next, in step S6, a GET command for the data to be acquired is issued to the server 7. This GET command is issued to the server 7 via the network interface 3 and the network 32.

As a result, in the server 7, the data designated by the GET command is transferred to the image forming apparatus 1 via the network 32 and the network interface 3.
Send to.

When the reply from the server 7 is thus received, the process proceeds from step S7 to step S8, and the image data is generated in the image memory 2 based on the data received from the server 7. Next, the process proceeds to step S9. If the "Content-type" stored in step S5 is a JPEG image, the process proceeds to step S10. If not, step S1.
Go to 2. In step S10, image processing for JPEG images is set in the image processing circuit 4. That is, UC
In the R circuit 10, the UCR is set to 80%, and the PWM circuit 11 is set to perform PWM at a frequency of 1/2.

The correction data of the LUT 302 is 1/2
The correction data for PWM modulation at the frequency is stored.

Further, based on the information of "Content-type",
From the CPU 101 to the CPU 202, the image with the gradation priority J
Notify that the format is PEG. In the CPU 202,
As will be described later, when printing the corresponding image, the gradation-priority process condition is set in the image forming unit.

On the other hand, if it is determined in step S9 that the image is not a JPEG image, the flow advances to step S12 to set the GIF image in the image processing circuit 4. That is, the UCR circuit 10 is set to UCR 100%, and the PWM circuit 1
1 is set to perform PWM at the same frequency as the clock signal 41.

As the correction data of the LUT 302, the correction data for PWM modulation at the same frequency of the clock signal 41 is stored.

Further, based on the information of "Content-type",
The CPU 101 notifies the CPU 202 that the image is in the resolution-preferred GIF format. In the CPU 202,
As will be described later, when printing a corresponding image, process conditions of resolution priority are set in the image forming unit.

Thus, step S10 or step S1
After the image processing and the PWM are executed by step 2, step S
At 11, the printer 5 executes image formation based on the image data that has undergone the image processing and the PWM processing. In addition, according to the JPEG image or the GIF image, image formation is performed at a resolution suitable for each,
The image data corrected by the correction data corresponding to each resolution is integrated by the integrator, and the integrated result is notified to the printer 5 as toner consumption amount prediction information.

When copying a document image, the operation unit 6 is used to specify the gradation priority mode or the resolution priority mode,
The CPU 101 may set whether the image processing and PWM modulation mode is the gradation priority mode or the resolution priority mode according to the mode designated from the operation unit 6.

As described above, the image formation can be performed based on the image data stored in the server 7 designated by the operation unit 6.

According to this processing, the JPEG image is UCR
Since the black component is extracted at 80%, it is possible to generate an image excellent in gradation connection of an image that transitions from black to another color, and perform PWM at 1/2 frequency. Therefore, it is possible to generate an image having excellent gradation.

Regarding the GIF image, UCR100
%, The black component is extracted, so a light gray image is formed only with black toner, which is a problem in the image generated by combining C, M, Y, and K. Gray is not pure gray. It is possible to avoid the situation of being lost. Further, since PWM has the same frequency as the supplied clock signal 41, it is possible to form a high-resolution image in which jaggies are not noticeable.

As described above, according to this embodiment,
The JPEG image is formed by image processing suitable for printing a natural image such as a photograph, and the GIF image is formed by image processing suitable for printing an illustration.

Then, the optimum image processing is performed on the image data, and the image data is integrated to predict an appropriate toner consumption amount of each toner color, and the printer is notified so that an appropriate developer toner is obtained. Toner replenishment control of the printer unit can be performed so that the density can be maintained.

Here, the setting of the process conditions of the image forming means, which is executed by the CPU 202 of the printer, will be described.

As described above, the data format (JPEG format or GIF format) of the image to be printed is notified from the CPU 101 to the CPU 202 of the printer section by the communication means 201. Then, with respect to the engine of the printer 5, the printing operation is performed by setting the process condition according to the data format.

As a specific example, for example, assuming that the charging voltage is Vc, the developing bias voltage is Vd, and the transfer voltage is Vt, Vc = V for the JPEG format with the gradation priority.
11, Vd = V12, Vt = V13, and Vc = V21, Vd = V22 for the resolution-oriented GIF format.
Let Vt = V23.

As described above, by switching the setting of the process condition of the image forming means according to the format of the image data to be printed, the optimum reproduced image can be obtained.

In the above example, it is proposed that the charging voltage, the developing bias, and the transfer voltage are all switched, but it goes without saying that at least one of these conditions may be switched.

Further, as a parameter of the process condition,
Although the example in which the voltage values for charging, development, and transfer are switched has been described, the current values may be switched in a configuration in which constant current control is performed, for example.

For example, if the value of the output current (transfer current value) of the high-voltage power supply used for transfer is It, then JP with gradation priority will be given.
For EG format, set It = I1 and set resolution priority G
For the IF format, It = I2.

In this way, by changing the transfer current value according to the format of the image data to be printed, optimum image reproduction is possible.

The CPU 202 on the engine side can select and switch the parameters of the above process conditions according to whether the image data to be printed is in the JPEG format or the GIF format. In advance, in a non-volatile memory (not shown) provided inside or outside the CPU 202, process condition information for each file format is stored as a lookup table for associating image feature information with process condition parameters. When the characteristic information of the image data is received from the CPU 101, the parameter of the process condition of the image forming unit of the printer unit may be changed to the corresponding parameter to optimize the process condition.

In that case, for example, Vc = V11, Vd = V12, Vt is set as the process condition in the JPEG format above the address in the nonvolatile memory of the CPU 202.
= V13 and It = I1 are stored, and Vc = V21, Vd = V22, and Vt = V are stored under the address as process conditions in the GIF format.
Information on parameters such as 23 and It = I2 is stored. Then, when the characteristic information of the image data is received from the CPU 101, the information of the parameter of the corresponding process condition is read from the address in the nonvolatile memory of the CPU 202 according to the JPEG format or the GIF format, and the image formation is performed. You may comprise so that the optimal conditions may be set for the means.

Of course, the JPEG format and GI exemplified here are used.
It goes without saying that it can be configured to be compatible with image files and data formats other than the F format.

For example, in printing a text document,
In particular, since it is required to clearly reproduce the edges and thin lines of characters, it is effective to set the image forming conditions with priority on resolution. Therefore, the image forming process may be performed with priority on the resolution for a file with the extension ".txt".

Further, by changing the conditions (parameters) of the image forming process to the optimum conditions in this way, it becomes possible to obtain a high-quality print output according to the characteristics of the image. It is also conceivable that the toner consumption amount changes as the conditions are changed. In such a case, it is conceivable that the difference between the predicted toner consumption amount in the image processing circuit and the actual toner consumption amount becomes large, causing a problem.

As an example of such a problem, when a large amount of printing is performed, the toner replenishment control is not properly performed, the toner density in the developing device cannot be maintained at an appropriate density, and the print density is Poor image density such as lightening or darkening, or in the worst case, the carrier in the developing device may adhere to the photosensitive drum, or the developer may overflow, resulting in damage to the device. Can also happen.

In order to prevent such trouble, the toner consumption amount prediction information may be corrected in accordance with the characteristics of the image in the prediction of the toner consumption amount in the image forming apparatus.

For example, in relation to image characteristics such as whether the image data format is the JPEG format or the GIF format and whether or not to change the optimum process condition for the image characteristics, it is possible to predict the toner consumption amount in the image processing circuit. LUT 302 used
The content of may be changed to an optimum correction value.

As a specific example, both the GIF format image data and the text format document data are suitable for printing in the resolution priority mode.
Since the format also handles figures and tables other than characters, the optimum process conditions differ from text-format document data that handles only characters. For example, when there is a difference between the toner consumption amount under the process condition where the character edge reproduction is made clear and printing is performed in the legible text and the toner consumption amount under the process condition in the GIF format, The correction data of the LUT 302 may be rewritten so that the toner consumption amount can be accurately predicted. Particularly in text data and the like, the ratio of the edge portion tends to increase, so it is effective to set a correction value that corrects the toner amount consumed in the processing of the edge portion in the electrophotographic process.

As described above, in the image processing circuit, the image processing for the image data is changed in accordance with the characteristics of the image data to be printed, such as at least an image requiring gradation and an image requiring resolution. By correcting the value of the prediction information of the toner consumption amount according to the image processing and according to the image forming process condition (parameter) of the image forming unit, an appropriate value according to the characteristics of the image to be printed can be obtained. Image formation and toner replenishment control are possible.

In this embodiment, an example in which the process conditions (parameters) of charging, development and transfer are changed has been described, but it goes without saying that other process conditions may be changed without departing from the spirit of the present invention. Good.

Further, the effects peculiar to this embodiment are as follows.

Since the storage position of the data to be acquired is specified by the operation unit 6 of the image forming apparatus 1, the image forming apparatus 1 alone can perform the image processing and the image forming processing, and other client apparatuses are not required. Appropriate image processing and proper toner consumption amount prediction can be performed according to the type of image data to be acquired.

Since the storage position of the data to be acquired is specified by the operation unit 6 of the image forming apparatus 1, the communication software can be simplified and the software can be easily developed.

To inquire the "Contents-type" to the server and judge the image format based on the result,
Even if there is no URL extension, it can be printed normally.

[Second Embodiment] The second embodiment of the present invention will be described below. In the following description, the first
The description of the same parts as those of the first embodiment will be omitted, and
The characteristic part of the embodiment will be mainly described.

As a second embodiment, the network 30
As an example, an image forming apparatus that acquires desired data based on a URL input by another apparatus connected to the HTTP protocol by HTTP protocol and generates image data based on the acquired data to form an image is formed. Explain.

In this embodiment, the position information in which the acquired data is stored is input as the URL from the client device 24 connected to the network 30, and the information of the input URL is input to the image forming apparatus 1. The image forming apparatus 1 receives the data from the server 7 and then forms the image.

FIG. 5 shows an image forming apparatus 1 according to the second embodiment.
FIG. 2 is a block diagram showing the overall configuration of a network system including the above, in which parts common to those in FIG.

In FIG. 5, reference numeral 24 is a client device, which has a function of designating the data that the image forming apparatus 1 acquires and forms an image. An image processing circuit 4a basically performs substantially the same function as the image processing circuit 4 described above, but its configuration will be described later with reference to FIG. Reference numeral 5a is a printer, the configuration of which will be described in detail with reference to FIG.

FIG. 6 shows an image processing circuit 4a according to the second embodiment.
3 is a block diagram showing the configuration of FIG. 2 and the same parts as in FIG.

In FIG. 6, reference numeral 8 is a DMA data transfer circuit for controlling the DMA transfer of image data from the image memory 2.
Reference numeral 25 is a gamma conversion circuit that performs gamma conversion, and 26 is a binarization circuit that binarizes the input image data to generate binary data. Reference numeral 45 is an R data signal which means the red component data of the image data, 46 is a G data signal which means the green component data of the image data, 47 is a B data signal which means the blue component data of the image data, and 48 is R data signal converted by the gamma conversion circuit 25, 4
Reference numeral 9 is a G data signal converted by the gamma conversion circuit 25, and 50 is a B data signal converted by the gamma conversion circuit 25. Reference numeral 39 is a color selection signal for selecting a color for forming an image, 51 is a binarization method selection signal for selecting a binarization method in the binarization circuit 26, and 52 is LE.
This is an LED drive signal for controlling the lighting of the D array.

The DMA data transfer circuit 8 is connected to the system bus 30 and is controlled by the CPU 101 which controls the entire image forming apparatus 1 via the system bus 30. When the image data held in the image memory 2 is transferred to the image processing circuit 4a by the DMA transfer by the DMA data transfer circuit 8, the CPU 101 first sets D
For the MA data transfer circuit 8, the address of the image memory 2 in which each of the R, G, and B image data is held and the data size to be transferred are set. After that, the DMA data transfer circuit 8 causes the printer 5a to print. In synchronization with the operation, the R, G, and B image data are sequentially read from the image memory 2 by the DMA, and the read data are sent to the gamma conversion circuit 25 as the R data signal 45, the G data signal 46, and the B data. The signal 47 is output. This output is performed in synchronization with R, G, B data. That is, the R, G, B data of each pixel are simultaneously output.

The R data signal 45, G data signal 46, and B data signal 4 thus input to the gamma conversion circuit 25.
7 is gamma-converted based on a preset gamma conversion table, and R data signal 45 to R data signal 4
8, G data signal 46 to G data signal 49, and B data signal 47 to B data signal 50 are generated and output. R output from these gamma conversion circuits 25
Data signal 48, G data signal 49, B data signal 50
Is input to the binarization circuit 26. The binarization circuit 26 selects which color is output based on the color selection signal signal 39, and which binarization method is selected based on the binarization method selection signal 51. decide. In the present embodiment, it is assumed that the binarization circuit 26 can select either one of two binarization methods, a dither method and an error diffusion method.

Here, in the dither method, based on each luminance data, the luminance data is converted into a binary pattern based on a binarized pattern which expresses a density corresponding to the luminance as an area gradation, and an image is formed. This is a method of generating data for use. This dithering method is a binarization method suitable for printing such as illustrations, drawings, characters, etc., in which gradation transitions are small and the boundaries of regions are clear.

On the other hand, the error diffusion method is based on the error between the original data of the pixel to be binarized, the original data of the binarized peripheral pixel, and the data generated by the binarization, and the random number. Is a binarization method for binarizing the pixel,
This is a binarization method suitable for natural images such as photographic data with many gradation transitions.

The image data binarized in this way is the LED
The drive signal 52 is output to the printer 5a.

As the binarized image data, L
The ED drive signal 52 is also sent to the integrator 303, and the integrator 3
It is integrated with 03. The integrator 303 may be a simple up-counter because it is an area gradation based on binary data, and in that case, an integrator with a small circuit is sufficient as compared with the case of PWM modulation. Further, integration is performed for each image data corresponding to each toner color, and the integration result is read by the CPU 101 and stored in the memory 102. CPU 101
The integrated result stored for each toner color is read from the memory 102 and immediately notified to the CPU 202 of the printer 5a as toner consumption amount prediction data.

FIG. 7 is a block diagram showing the structure of the printer 5a of the present embodiment, and the parts common to those in FIG. 3 described above are indicated by the same numbers.

In FIG. 7, 27 is an LED drive signal 52.
LED array in which each element emits light according to
A photosensitive drum on which a latent image is formed by turning on each element of the array, and an image is formed by adsorbing toner to the latent image,
Reference numeral 16 is a revolver which holds the C, M, Y and K toner cartridges and rotates according to the color to be developed.
17 is a C (cyan) toner cartridge, 18 is an M (magenta) toner cartridge, 19 is a Y (yellow) toner cartridge, 20 is a K (black) toner cartridge, and each cartridge is the same as in the first embodiment.
It is composed of a toner bottle and a developing device. 21 is a transfer drum for adsorbing the paper and transferring the toner of the developing device onto the paper; 22 is a fixing drum for fixing the toner onto the paper; 23 is a paper holding member for feeding the paper during image formation. A paper cassette, 52 is an LED drive signal, and 44 is a paper transport path.

The printer 5a is a printer for forming an image by an electrophotographic method, and a color image is formed on a sheet by four color toners of C (cyan), M (magenta), Y (yellow) and K (black). To form. The image is developed using an LED array, which is different from the laser system described above.

When forming an image, first the paper feed cassette 2
The sheets stacked in 3 are fed, and the sheets are conveyed in the sheet conveyance path 4
4 is conveyed, adsorbed by the transfer drum 21 and stuck to the surface of the transfer drum 21. The transfer drum 21 rotates at a constant speed, and the paper also moves according to the rotation of the transfer drum 21. When printing with the printer 5a, LE
The D drive signal 52 is supplied from the image processing circuit 4. The supplied LED drive signal 52 is an image signal of any one of C, M, Y, and K generated by the binarization processing of the binarization circuit 26, and the image signal of C is first input.

In the LED array 12, the LEDs are linearly arranged corresponding to the width of the photosensitive drum 15, and one LED has a size corresponding to the width of one pixel. When the LED drive signal 52 supplies the image data for one scanning line to be developed, the latent image formation for one scanning line is performed by the light emission of the LED. L of the part where the LED drive signal 52 is on
The ED is turned on and the potential of the photosensitive drum 15 is high, and the other portion is not turned on and the potential of the photosensitive drum 15 is lowered to form a latent image.

The latent image thus formed on the photosensitive drum 15 is first stored in the C toner cartridge 17 at a portion where the C toner cartridge 17 and the photosensitive drum 15 which are previously arranged in a portion where the revolver 16 and the photosensitive drum 15 are in contact with each other. In contact with the negatively charged cyan toner stored in the developer coated on the developing sleeve of the developing device. The cyan toner is attracted and developed only by the laser-irradiated portion of the photosensitive drum by an electric attraction force. The portion of the photosensitive drum 15 to which the toner is adsorbed moves to the portion in contact with the transfer drum 21 due to the rotation of the photosensitive drum 15. At the portion where the transfer drum 21 and the photosensitive drum 15 are in contact with each other, the toner attracted to the photosensitive drum 15 is transferred onto the sheet attracted to the transfer drum 21.

Thereafter, the revolver 16 is ¼ of the entire circumference so that the M toner cartridge 18 contacts the photosensitive drum 15.
Is only rotated. Then, the M image signal is input to the laser drive signal 42, and the magenta toner is transferred onto the sheet in the same manner as the C development. When developing each color, the color selection signal 39 indicates that when developing C, the image data of C is the LED.
It is set to output to the drive signal 52, and M, Y, K
Image data of M, Y, K respectively when developing
It is set to be output to the drive signal 52. Similarly, Y, K development is also performed, and the toners of C, M, Y, K colors are transferred onto the sheet adsorbed on the transfer drum 21.

Thereafter, the sheet is separated from the transfer drum 21 and passes between the two fixing devices 22 through the sheet conveying path 44. At this time, the fixing device 22 heats and pressurizes,
The toner image transferred onto the paper is fixed on the paper and is discharged to the outside of the printer 5a. When the printing operation is performed in this manner and the printing operation in the printer 5 is performed in this way, the toner in the developing device is consumed. Therefore, in the two-component developing method including the toner and the magnetic carrier,
It is necessary to perform toner replenishment control for replenishing the appropriately consumed toner to the developing device so as to maintain an appropriate toner concentration.

Therefore, along with the printing operation, the CPU 1
01 to the CPU 202 of the printer 5a, based on the toner consumption amount prediction information for each toner color, the CPU
202, C, M, Y, K toner cartridge 1
The toner is controlled to be replenished from the toner bottles 7, 18, 19, and 20 into the developing devices for the respective toner colors.

FIG. 8 is a flow chart showing the processing in the image forming apparatus 1 of the second embodiment, and the control program for executing this processing is stored in the memory 102.

As shown in FIG. 5, the image forming apparatus 1 of the second embodiment is connected to the client device 24 via the network 32. This client device 24
Is a data processing device capable of inputting a character string by a user such as a personal computer. In this client device 24, the user inputs data instructing the data to be printed by the image forming apparatus 1. The format of this data is URL as in the first embodiment.

The user of the client device 24 uses this U
After inputting the RL, the input URL is transmitted to the image forming apparatus 1 via the network 30. The URL sent in this way is
It is received by the image forming apparatus 1 via the interface 3. The image forming apparatus 1 waits for input until this input is made (step S21). Step S21
When the URL is input, the process proceeds to step S22, the structure of the input URL is analyzed, and the address of the server holding the desired data and the position of the data to be acquired in the server are specified. . Here, it is assumed that the server 7 has data to be acquired.

Then, the process proceeds to step S23, and the GET command for the data to be acquired is issued to the server 7. This GET command is issued to the server 7 via the network interface 3 and the network 32.

As a result, in the server 7, the data specified by the GET command is transferred to the image forming apparatus 1 via the network 32 and the network interface 3.
Send to.

When the reply from the server 7 is received in this way, the process proceeds from step S24 to step S25, and the image data is generated in the image memory 2 based on the data received from the server 7. Then, the process proceeds to step S26 and step S
The extension of the URL analyzed in 22 is ", JPG" or ".jpe"
It is determined whether it indicates a JPEG image such as "g".

When the image is a JPEG image, step S27.
Then, the process proceeds to step S1 and sets the image processing for the JPEG image in the image processing circuit 4a. That is, the gamma conversion circuit 9 sets the gamma table for the natural image, and the binarization circuit 10 sets the binarization method by the error diffusion method.

Furthermore, based on the extension information of the URL analyzed in step S22, if the image is a JPEG image, C
From the PU 101 to the CPU 202, the image with gradation priority J
Notify that the format is PEG. In the CPU 202,
When printing a corresponding image, process conditions (parameters) giving priority to gradation are set in the image forming means.

On the other hand, if it is determined in step S26 that the image is not a JPEG image, the process advances to step S29 to set the GIF image in the image processing circuit 4a. That is, the gamma conversion circuit 9 sets the gamma conversion table for the illustration, and the binarization circuit 10 sets the binarization method by the dither method.

Thus, step S27 or step S2
After the image processing and the binarization processing are performed by 9, the process proceeds to step S28, and the printer 5a executes the image formation based on the image data subjected to the image processing and the binarization processing. Further, the image data binarized by the error diffusion method for the JPEG image and the dither method for the GIF image are integrated by the integrator for each toner color, and the integrated result is notified to the printer 5 as toner consumption amount prediction information. .

In this way, the process of forming an image based on the data stored in the server 7 designated by the client device 24 is completed.

According to the processing described above, the JPEG image is subjected to gamma conversion for a natural image, and further binarized by the error diffusion method. Therefore, an image is formed with a tint suitable for a natural image and binarization. Can be done.

Further, the gamma conversion for the illustration is performed on the GIF image and further binarized by the dither method, so that the image can be formed with the tint and binarization suitable for the illustration. is there.

However, all of them are converted into binary data, and in printers at a low cost, the number of dots is integrated by integrating the binary data. Since the consumption amount is proportional to the number of dots, the integrating circuit can be simplified.

Further, as described above, in the present embodiment, it is determined whether the data format of the image to be printed is the JPEG format or the GIF format based on the extension of the image file included in the URL, and the determination result In response, the CPU 101 notifies the CPU 202 of the printer unit by the communication unit 201. On the engine side, a printing operation is performed by setting process conditions according to the data format. Specifically, as in the first embodiment, an optimum reproduced image can be obtained by switching each process condition (parameter) of image formation.

As with the first embodiment, the switching parameter may be at least one of the charging voltage, the developing bias and the transfer voltage. Furthermore, for example, in a device using a high-voltage power supply that performs constant current control, the current value may be switched.

As described above, according to this embodiment,
JPEG images are formed by image processing suitable for printing natural images such as photographs, and GIF images are formed by image processing suitable for printing illustrations, etc. Even with the adjustment method, it is possible to notify the toner consumption amount information to the printer unit and perform appropriate process condition (parameter) setting and appropriate toner supply control.

The effects peculiar to the second embodiment are as follows.

The client device can specify the address at which desired data is stored, and the image forming device 1 does not require an operation unit for specifying the address, thereby reducing the cost.

Appropriate binarization processing according to the type of image is possible.

Since the image type is discriminated by the extension of the URL, it can be applied to protocols other than the HTTP protocol.

As described above, in both the first and second embodiments, the image processing unit is configured to predict the toner consumption amount from the image data and notify the printer unit of the toner consumption amount.
Regardless of the configuration of the image forming unit, the control of toner supply of the printer unit can be made substantially the same, and even if the image forming apparatus is configured so that various image processing boards are connected to the printer unit, There is an advantage that it is not necessary to significantly change the control of.

As described above, even when a flexible image processing board capable of various image processings is used according to the cost and function desired by the user, there is no additional cost for the printer unit and the printer unit Since the designs can be shared, there are advantages that the development period of the printer unit can be shortened and that the printer unit can be easily shared.

Further, even if there are various combinations of various image data from the network and the image forming apparatus for printing, there is an advantage that appropriate process conditions can be set and appropriate toner supply control can be performed.

[Third Embodiment] The third embodiment of the present invention will be described below. In the following description, the second
The description of the same parts as those of the first embodiment will be omitted, and
The characteristic part of the embodiment will be mainly described.

As described above, when the image forming apparatus is configured to automatically set the process conditions, the image processing unit performs the extraction process for extracting the characteristics of the image data to be printed, and the extracted image is extracted. In general, it is configured so that the type of image is determined and the process condition in the apparatus is set to the optimum condition.

However, in such a configuration, since it is necessary to perform the feature extraction processing of the image data before actually printing, it takes time to set the image forming conditions,
There is a problem in that it takes a long time to actually start the printing operation and the throughput decreases.

In this embodiment, the waiting time until the start of the printing operation is shortened and the printing operation is not interrupted.
An image forming apparatus capable of setting process conditions suitable for an image to be printed.

The processing in the image forming apparatus of this embodiment will be described below. The process of the image forming apparatus of the present embodiment is a modification of part of the process of the image forming apparatus of the second embodiment, and will be described with reference to the flowchart of FIG.

In the second embodiment, step S2
The extension of the URL analyzed in 2 is not used until step S26, but in the present embodiment, in step S22,
Image file format to print is ", JPG" or ".jpeg"
It is determined based on the extension of the image file whether or not it is a JPEG image.

Furthermore, in step S22, it is determined whether the image data to be printed is in the JPEG format or the GIF format.
The communication means 201 notifies the CPU 202 of the printer unit from the CPU 101. Upon receipt of this, the engine side performs a predetermined predetermined operation so that the process condition according to the data format can be set in a short time.

The predetermined operation includes, for example, a charging operation for bringing the surface potential of the photosensitive drum 15 to a predetermined surface potential and a preliminary operation such as a cleaning operation for cleaning unnecessary toner on the photosensitive drum 15. .

Further, as a predetermined operation, a calibration operation for correcting the gradation reproduction of the image forming means may be performed.

For example, in the case of the JPEG format, the calibration operation is performed so that the gradation reproducibility of the printer becomes appropriate so that the gradation operation is performed in the gradation priority mode. Then, the image processing unit performs steps S23 and S2.
4, after the image data is generated through S25 and both the image processing unit and the printer unit are ready to print, the image data subjected to the JPEG image processing is transmitted to the printer unit in step S27, It is possible to obtain a reproduced image suitable for the data format by performing the printing operation under the process condition in the gradation priority mode.

On the other hand, in the case of the GIF format, the calibration operation is carried out so that the resolution of the printer becomes appropriate so that it operates in the resolution priority mode.
In this case, since the gradation reproducibility is not the highest priority, a simple calibration operation that requires only a short time or the calibration operation itself may not be performed. Then, the image processing unit performs steps S23, S24, S
After 25, image data is generated, and when both the image processing unit and the printer unit are ready to print, the image data subjected to the GIF image processing is transmitted to the printer unit in step S27, and the resolution priority mode is set. It is possible to obtain a reproduced image suitable for the data format by performing the printing operation under the process condition of 1.

[Other Embodiments] In the above description, the first to third embodiments have been described independently.
The invention is not so limited and the features of one or more embodiments may be combined. For example, the printer 5a of the second embodiment may be adopted in the first embodiment. The image processing circuit 4 of the first embodiment may further include the function of the image processing circuit 4a of the second embodiment,
Further, both of the image processing circuits 4 and 4a may be provided with not all of the image processing functions shown in FIGS. 2 and 6 but only a part thereof.

In the first embodiment, the type of image data is discriminated based on the format information from the server,
UCR processing of image data is performed according to the type of image data, and C, M, and
The multivalued image data of Y and K are corrected by the LUT 302, and the corrected data are integrated by the integrator 301. However, as described in the second embodiment, the image data is discriminated by the URL extension, It goes without saying that the present invention can also be applied to the case of performing PWM modulation by multi-valued image data in the image processing circuit of the first embodiment.

As described above, in the image processing circuit of the first embodiment, when the image type is discriminated by the URL extension, the image processing is switched to an appropriate one depending on whether it is a JPEG image or a GIF image. As a result, it is possible to appropriately select the gradation priority or the resolution priority.

That is, when the extension of the URL determines that the image is a JPEG image, gradation priority processing is selected, PWM modulation of half the frequency of the clock signal is performed, and image data is also integrated when gradation priority is applied. The correction data is selected by the LUT 302, integrated by the integrator 301, the integrated result is notified to the printer 5, and gradation-priority process conditions (parameters) for image formation are set in the image forming means.

If it is determined that the image is a GIF image, resolution priority processing is selected, PWM modulation is performed in the cycle of the clock signal, and correction data with resolution priority is selected by the LUT 302 and integrated by the integrator 301. Then, the integrated result is notified to the printer unit 5, and process conditions (parameters) of resolution priority regarding image formation are set in the image forming unit.

As described above, since the appropriate image processing is selected and the image data integration processing is appropriately corrected depending on the extension of the URL, the toner consumption amount is predicted well and the printer unit In No. 5, it is possible to maintain the proper toner density. At the same time, regarding image formation, it is possible to set a more suitable process condition in which priority is given to gradation or resolution depending on the format of the image data to be printed, to the image forming means, thereby forming an image suitable for the image. To do.

Even when the present invention is applied to a system composed of a plurality of devices (eg, host computer, interface device, reader, printer, etc.), a device composed of one device (eg, copier, facsimile). Device).

Further, an object of the present invention is to supply a storage medium having a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to supply a computer (or CPU) of the system or apparatus.
Or MPU) reads and executes 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.

As a storage medium for supplying the program code, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD
-R, magnetic tape, non-volatile memory card, ROM, etc. can be used.

Further, by executing the program code read by the computer, not only the functions of the above-described embodiment are realized, but also the OS (operating system) running on the computer based on the instruction of the program code. ) And the like perform some or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written in the memory provided in the function expansion board inserted in the computer or the function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that a case where the CPU or the like included in the function expansion board or the function expansion unit performs some or all of the actual processing and the processing realizes the functions of the above-described embodiments is also included.

When the present invention is applied to the above storage medium, the storage medium stores the program code corresponding to the above-described flowchart (shown in FIG. 4 and / or FIG. 8).

[0186]

As described above, according to the present invention, an image having a flexible structure in which main image processing functions can be integrated in an image processing board as an image processing means and various image processing can be performed. Even when the processing board is used in the image forming apparatus, an appropriate image forming condition can be set based on the image data, and an image printing operation suitable for the type of image to be printed can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a system including an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of an image processing circuit according to the first embodiment.

FIG. 3 is a block diagram showing the configuration of the printer of the first embodiment.

FIG. 4 is a flowchart illustrating processing performed by the image forming apparatus according to the first exemplary embodiment.

FIG. 5 is a block diagram showing a system configuration including an image forming apparatus according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of an image processing circuit according to a second embodiment.

FIG. 7 is a block diagram showing a configuration of a printer according to a second exemplary embodiment.

FIG. 8 is a flowchart illustrating processing in the image forming apparatus according to the second exemplary embodiment.

Continued front page    F term (reference) 2H027 DB01 DE07 EA01 EA03 EA05                       EA06 EB03 EC06 EC20 EE08                       EE10 EJ13 EJ15 ZA07                 2H077 DA08 DA78 DB02 GA04                 2H200 FA18 GA23 GA34 GA47 JA29                       JB02 JB25 PA05 PB29                 5C074 AA20 BB02 BB26 DD03 DD14                       EE12 GG13

Claims (15)

[Claims] 1. An image forming apparatus for forming an image according to an electrophotographic method, comprising: storage means for storing image data; and image processing means for performing image processing on the image data stored in the storage means. An image forming unit that forms an image using a developer based on the image data processed by the image processing unit, the image forming unit based on the image data. The image forming means includes characteristic information notifying means for notifying the image forming means of characteristic information related to the image forming condition, and the image forming means sets the image forming condition according to the characteristic information notified by the characteristic information notifying means An image forming apparatus characterized by being changed. 2. The image processing means changes the image processing for the image data based on whether an image requiring gradation or an image requiring resolution, and the feature information notifying means executes The image forming apparatus according to claim 1, wherein the characteristic information is notified according to the image processing performed. 3. The image processing means determines, based on an extension included in a file name of the image data, whether the image requires gradation or an image requiring resolution. The image forming apparatus according to claim 2. 4. The image forming unit changes at least one of charging, developing, and transferring conditions in accordance with the characteristic information notified from the image processing unit. The image forming apparatus according to claim 1. 5. The image forming unit changes at least one condition of a preliminary operation and a calibration operation according to the characteristic information notified from the image processing unit. The image forming apparatus according to any one of 4 above. 6. The image forming apparatus is connected to a network, and issues an image request to the network based on information input by the input unit for inputting information about image data. 6. The device according to claim 1, further comprising an issuing unit, wherein the storage unit stores the image data transmitted in response to the image request from the issuing unit. Image forming apparatus. 7. The reading means for reading an original image to generate image data is further provided, and the storage means stores the image data generated by the reading means. The image forming apparatus according to any one of items. 8. The image processing means includes a developer consumption amount calculation means for generating information on an amount of the developer expected to be consumed by the image forming means, based on the image data subjected to the image processing. 8. The image forming apparatus according to claim 1, wherein the image forming unit replenishes the developer according to the information generated by the developer consumption calculating unit. . 9. The image processing means changes the image processing for the image data based on whether the image requires gradation or an image requiring resolution, and changes the image processing according to the executed image processing. The image forming apparatus according to claim 8, further comprising a correction unit that corrects the information. 10. The image forming unit, when changing the image forming condition of the image forming unit, supplies the developer according to the changed image forming condition. Image forming device. 11. A method of setting image forming conditions of an image forming apparatus for forming an image according to an electrophotographic method, comprising: a storing step of storing image data in a storage means; and the image data stored in the storage means. An image processing step of performing image processing, and an image forming step of forming an image using a developer based on the image data processed in the image processing step, wherein the image processing step is the image An image processing changing step of changing image processing for the image data based on whether the data is an image requiring gradation or an image requiring resolution, and the image forming according to the changed image processing. And a characteristic information notifying step of notifying characteristic information related to image forming conditions in the step, wherein the image forming step is performed in accordance with the characteristic information notified in the characteristic information notifying step. Image forming condition setting method for an image forming apparatus characterized by changing the. 12. The image processing step determines whether the image requires gradation or an image requiring resolution based on an extension included in a file name of the image data. The image forming condition setting method for an image forming apparatus according to claim 11. 13. The image forming step according to claim 11, wherein at least one of charging, developing and transferring conditions is changed in accordance with the characteristic information notified in the characteristic information notifying step. 13. An image forming condition setting method for an image forming apparatus according to item 12. 14. The image forming step changes at least one condition of a preliminary operation and a calibration operation according to the characteristic information notified in the characteristic information notifying step. 14. The image forming condition setting method for an image forming apparatus according to any one of 1 to 13. 15. The image forming apparatus is connected to a network, and an input step of inputting information about image data, and an image request is issued to the network based on the information input in the input step. 15. An issuance step is further provided, and the storage step stores image data transmitted in response to the image request issued in the issuance step. An image forming condition setting method for an image forming apparatus according to.