JP2000207164A - Image forming apparatus and image processing method in the apparatus - Google Patents

Abstract

(57) Abstract: An address at which desired image data is stored is designated, desired data is read from the designated address to form an image, and image processing is performed according to the type of the image data. To form an image. An image forming apparatus is connected to a network and forms an image based on image data obtained from the network. When an address and a type of image data are input from an operation unit, the input is performed. An image request is issued to the server 7 via the network 30 based on the received information. The image data transmitted from the server in response to the image request is stored. If the type of the stored image data is the JPEG format, the image processing circuit 4 executes image processing with emphasis on gradation, If it is a GIF, image processing is performed with emphasis on resolution, and the processed image data is output to the printer 5 to form an image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus connected to a network, capable of forming an image by accessing the network and acquiring image data, and an image processing method in the apparatus.

[0002]

2. Description of the Related Art In recent years, WWW (Worl) on which various information
d Wide Web) server and HTTP (Hyper T
It has become possible to connect a computer equipped with dedicated software (hereinafter referred to as a browser) for accessing by ext Transfer Protocol (hereinafter referred to as "browser") over a network, and to refer to information on a WWW server from the computer. Also, this browser can take in the information on the WWW server into the computer and store it. Therefore, the user who wants to print this data outputs the data temporarily stored in the computer to a printer device having a printing function and prints the data, so that W
Various data of the WW server can also be printed.

[0003]

However, in the conventional apparatus, it is possible to print information obtained from a WWW server, but at the time of printing, fixed image processing is always performed regardless of the content of the information. Had been done,
There were the following disadvantages. The same image processing is applied to images where importance is placed on gradation, such as photographic data, and images, etc., where resolution is important, such as illustrations. The resolution of the image is lost. Since gamma conversion processing according to an image such as photographic data and an image such as an illustration is not performed, it is not possible to output an image with an optimum tint according to each image. Since the same undercolor processing is performed on an image such as photographic data and an image such as an illustration, it is not possible to output an image with an optimal tint.

The present invention has been made in view of the above-mentioned conventional example, and designates an address at which desired image data is stored, reads out desired data from the designated address, forms an image, and forms the image. It is an object of the present invention to provide an image forming apparatus that forms an image by performing image processing according to the type of data, and an image processing method in the apparatus.

Another object of the present invention is to provide an image forming apparatus which captures desired data from a network address designated by a user's operation via a network, performs image processing according to the captured data, and forms an image. An object of the present invention is to provide an image processing method in the device.

Another object of the present invention is to obtain desired data from a network address specified by a client device connected to the network via a network, and perform image processing according to the captured data to form an image. And an image processing method in the image forming apparatus.

[0007]

In order to achieve the above object, an image forming apparatus according to the present invention has the following arrangement.
That is, an image forming apparatus that is connected to a network and forms an image based on image data obtained from the network, and an input unit that inputs information about the image data, and an input unit that inputs information based on the information input by the input unit. Issuing means for issuing an image request to the network, storage means for storing image data transmitted in response to the image request by the issuing means, and a type corresponding to the type of image data stored in the storage means. The image processing apparatus is characterized by including image processing means for controlling image processing to be executed, and image forming means for forming an image based on image data processed by the image processing means.

To achieve the above object, an image processing method in an image forming apparatus according to the present invention includes the following steps. That is, an image processing method in an image forming apparatus connected to a network and performing image formation based on image data obtained from the network, wherein an input step of inputting information related to the image data, An issuance step of issuing an image request to the network based on information; a storage step of storing image data transmitted in response to the image request in the issuance step in a memory; and image data stored in the memory An image processing step of controlling to execute image processing corresponding to the type of
An image forming step of forming an image based on the image data processed in the image processing step.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the present embodiment in detail, the features of the present embodiment will be briefly described.

For example, on the Internet now,
GIF, JPEG, and the like are generally used as image file formats. The GIF file format is a file format in which images are compressed by lossless compression and stored, and the number of colors that can be displayed is limited to 256 colors. For this reason, the GIF file format is often used for image data that does not require a large number of colors, such as illustrations and figures.

The JPEG file format is a file format for compressing and saving by irreversible compression, and can display a very large number of colors such as approximately 16.77 million colors. For this reason, the JPEG file format is often used mainly for image data of a natural image type such as data obtained by digitizing a photograph.

On the other hand, in printing an image by electrophotography or the like, if the resolution of the image to be printed is increased, it is difficult to make the waveform of an analog signal used as a pattern signal into an ideal triangular wave by pulse width modulation or the like. , It is difficult to print with ideal gradation.

Therefore, in this embodiment, an image for which importance is placed on resolution is printed at high resolution, and an image for which importance is placed on color gradation is printed at low resolution.

Furthermore, since image data such as illustrations and figures and image data such as photographs and natural images often have different settings for image enhancement processing or smoothing processing, in this embodiment, each image data Setting of image enhancement or smoothing in accordance with the format of.
In addition, in the case where image data of the RGB system is printed by an electrophotographic printer, image data expressed in RGB is converted into C (cyan), M (magenta), Y (yellow), and K (black). It is necessary to convert to a density value and send the converted image data to a printer. In this case, C
In a gray image printed using the MY toner, the gray color becomes a tinted gray, so it may be better to print the gray portion only with the black (K) toner. . Conversely, when a gray portion is printed only with black toner, and in the case of a gradation image that smoothly transitions from gray to another color, the reproduced gradation of the gradation portion is impaired. Therefore, in such an electrophotographic printer, image formation is generally performed by combining CMY toner and K toner at an appropriate ratio. The ratio between CMY and K in this case is called under color removal. In this embodiment, under color removal can be set according to the format of each image data.

In the case of a printer such as an ink jet printer in which the area of one pixel is not variable or the area of one pixel can be changed only by a very limited amount, the unit area is By changing the number of colored pixels per hit and the combination of the colored pixels, it is possible to print an image with gradation. Such a method of expressing an image is called area gradation. According to this method, original image data is converted into image data composed of only printable colors by a printer by dither processing or error diffusion. Can be printed. Even in such area gradation processing, when image data such as a photograph is printed, and when image data such as an illustration is printed, by applying an optimal conversion processing, it is possible to adapt to the format of each image data. It is possible to set the area gradation processing.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the present embodiment, a command is first transmitted to a server holding desired image data designated by a user using an operation unit using the HTTP protocol, and a command from the server is sent from the server. An image forming apparatus capable of acquiring image data held in the server in response to a reply and forming an image will be described.

FIG. 1 is a block diagram showing a configuration of an image forming apparatus 1 according to the present embodiment. The image forming apparatus 1 is connected to a network 32.

In FIG. 1, reference numeral 2 denotes an image memory which holds image data inputted from a network 32 via a network interface 3, for example. The network interface 3 controls communication with another device connected to the network 32 via the network 32. Reference numeral 4 denotes an image processing circuit which performs various types of image processing on 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. Reference numeral 6 denotes an operation unit which is used to designate a location (a server or the like) where image data to be printed using the printer 5 is held. Reference numeral 7 denotes a server which is connected to the network 32 and holds various image data. Reference numeral 30 denotes a system bus, which is a bus for transmitting and receiving data between the CPU 101 that controls the operation of the entire image forming apparatus 1 and each unit. A video bus 31 is used for transmitting 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, a CPU 1
01 is also used as a work area for temporarily storing programs executed by the CPU 101 and various data during the operation of the CPU 101.

Next, the HTTP protocol will be described.

The HTTP protocol is a service on the TCP / IP protocol used for transferring data described in HTML (Hyper Text Markup Language), image data, and the like. This is usually 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, HTT
Activate the P client, and in this HTTP client, the user specifies the position of the data on the server,
An input is made in an instruction format called a URL for designating a position where data is held. This allows HT
The TP client issues an information transfer request to the server according to the input.

In the HTTP protocol, there are a GET command which is a command for requesting data and a HEAD command which is a command for requesting related information on the data. Generally, what kind of data it is is determined in advance, then the data is acquired by a GET command, and processing is performed based on the acquired data.

The related information that can be obtained by the HEAD command includes information such as the size and update date of the data, as well as format information 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 the type of data from this extension.

Now, for example, if the host name of the server 7 is "ho
st.co.jp ”, if the location of the data to be obtained on the server is“ /pub/image.GIF ”, then“ http: // hos
By inputting the URL "t.co.jp/pub/image.GIF", the HTTP client causes the server "host.c
o.jp ”, first HE for“ /pub/image.GIF ”
Issue an AD command.

When the server 7 receives the message, "/ pub / ima"
ge.GIF ”data format information in the HEAD
HT that issued a HEAD command as a command reply
Send to TP client.

HT receiving the response to this HEAD command
Next, the TP client issues a GET command for “/pub/image.GIF” to the server “host.co.jp”.

The server 7 receiving this GET command
Transmits the data of "/pub/image.GIF" to the HTTP client that issued the GET command as a reply to the GET command.

H which has received the GET command reply in this way
The TTP client can receive the data of the format information “/pub/image.GIF” received as a reply to the HEAD command, and can process the received data.

Thus, the HTTP client:
Based on the URL input from the operation unit 6, the designated data stored in the designated 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 the present embodiment will be described.

FIG. 2 is a block diagram showing a configuration of the image processing circuit 4 according to the present embodiment.

In FIG. 1, reference numeral 8 denotes a DMA data transfer circuit which controls 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. Reference numeral 10 denotes a UCR circuit which performs UCR processing on CMY image data to generate CMYK image data 40. 11 is a PWM (Pulse Width Modulation) circuit, which is CMY
A laser drive signal 42 for controlling the lighting of the laser is generated from the K image data.

Reference numeral 33 denotes an R data signal representing data of a red component of the image data, 34 denotes a G data signal representing data of a green component of the image data, and 35 denotes a B data signal representing data of a blue component of the image data. , 36 are C data signals representing the data of the cyan component of the image data, 3
Reference numeral 7 denotes data of a magenta color component of image data.
A data signal 38 is a Y data signal indicating yellow component data of the image data, and 39 is a color selection signal for selecting a color for forming an image. 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 for controlling laser lighting.

The DMA data transfer circuit 8 is connected to the system bus 3
0, and is controlled by a CPU 101 that controls the entire image forming apparatus 1 via the system bus 30. When the image data stored in the image memory 2 is transferred to the image processing circuit 4 by DMA transfer under the control of the DMA data transfer circuit 8, first, the CPU 101 sends R, The address of the image memory 2 where the G and B image data are held, and the data size for DMA transfer are set. Thereafter, in synchronization with the operation of the printer 5, the DMA data transfer circuit 8 sequentially reads the data of each of R, G, and B from the address specified by the DMA in the image memory 2, and transfers the read data to the LOG conversion circuit 9. , An R data signal 33, a G data signal 34, and a B data signal 35. The output of the RGB data to the LOG conversion circuit 9 is performed by synchronizing three of R, G, and B data.
That is, the R, G, B data of each pixel of the image data is output simultaneously.

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

The C data signal 36, M data signal 37, and Y data signal 38 output from the LOG conversion circuit 9 are input to the UCR circuit 10. The UCR circuit 10 extracts and outputs a black component, which is a common part, from each data of C, M, and Y. The black component is extracted by determining the color having the minimum value of each of the C, M, and Y data for each pixel, and integrating the minimum value with a preset coefficient to obtain the black toner data. Is determined, and the value of each of the C, M, and Y data actually used for image formation is calculated by subtracting the value of the K data from each of the C, M, and Y data. This is achieved by:

For example, when the coefficient for generating data for black toner is 80% and C = 20, M = 90, and Y = 100, the minimum value is "20". Is generated.

C ′: 4 (CK) M ′: 74 (M−K) Y ′: 84 (Y−K) K: 16 (20 × 80% = 16) A signal 39 is input, which is necessary because the printer 5 employs an image forming method of forming an image of C, M, Y, and K one by one. This signal is used to select which of C ', Y', M ', and K image data to output at the time of each image formation.

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

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

Next, the configuration of the printer 5 according to the present embodiment will be described.

FIG. 3 is a block diagram showing a configuration of the printer 5 according to the present embodiment.

In FIG. 1, reference numeral 12 denotes a semiconductor laser which outputs a laser beam according to an input signal. Reference numeral 13 denotes a polygon mirror, whose side surface of a regular hexagon is mirror-finished, and rotates in response to driving of a polygon motor 14. Reference numeral 15 denotes a developing device.
A latent image is formed by the laser beam, and an image is formed by adsorbing toner onto the latent image. 16 is a revolver,
Each of the toner cartridges C, M, Y, and K is held and rotated according to the color to be developed. 17 is C (cyan)
A toner cartridge, 18 is an M (magenta) toner cartridge, 19 is a Y (yellow) toner cartridge,
Reference numeral 20 denotes a K (black) toner cartridge. 21
Denotes a transfer drum, which adsorbs the paper and transfers the toner in the developing device 15 onto the paper. Reference numeral 22 denotes a fixing drum for fixing toner on paper, 23 denotes a paper feed cassette that holds the paper and feeds the paper during image formation, 42 denotes a laser drive signal, and 43 denotes a laser drive signal.
Denotes a laser beam emitted from the semiconductor laser 12, and 44 denotes a paper transport path.

The printer 5 is a printer for forming an image by an electrophotographic system, and forms an image on a sheet of paper using four color toners of C (cyan), M (magenta), Y (yellow), and K (black). To form. When an image is formed, first, paper loaded in the paper feed cassette 23 is fed, and the paper is transported through a paper transport 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 moves in accordance with the rotation of the transfer drum 21.

On the other hand, when printing is performed in the printer 5, a 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 that has been PWMed by the circuit 11, and the data signal of C is input first. 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 output in this manner is applied to the polygon mirror 13.
Is irradiated. The polygon mirror 13 is rotated by rotation of a polygon motor 14, and the laser beam 43 is scanned from one end to the other end of the developing device 15 by this rotation. This one scan becomes one scan line in image formation. A latent image is formed on the developing device 15 by the scanning of the laser light. This latent image has electrical characteristics such that a portion irradiated with laser light has a high potential and a portion other than the portion has a low potential.

The latent image thus formed on the developing unit 15 is firstly stored in a portion where the developing unit 15 is in contact with a C toner cartridge 17 previously disposed at a portion where the revolver 16 and the developing unit 15 are in contact. , The negatively charged cyan toner stored in the container comes into contact with the toner. The cyan toner is developed by being attracted to only the portion of the developing device irradiated with the laser beam by the electric attraction force.
Then, the portion of the developing device 15 to which the toner is adsorbed moves to a portion in contact with the transfer drum 21 by the rotation of the developing device 15. In a portion where the transfer drum 21 and the developing device 15 are in contact with each other, the toner adsorbed on the developing device 15 is transferred onto the paper adsorbed on the transfer drum 21. Next, the revolver 16 is rotated by １ ／ so that the M toner cartridge 18 comes into contact with the developing device 15.
Is input, and a magenta toner image is transferred onto the sheet in the same manner as in the development of C.

In the same manner, development with the Y and K toners is also performed, and the toner images of C, M, Y and 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 drums 22 through a sheet transport path 44. At this time, the toner that is heated and pressed by the fixing drum 22 and transferred onto the paper is fixed on the paper,
The paper is discharged out of the printer 5. Printing is executed by the above operation.

Next, a processing operation in the image forming apparatus 1 of the present embodiment will be described with reference to a flowchart of FIG.

FIG. 4 shows an image forming apparatus according to this embodiment.
5 is a flowchart showing a control process executed by the PU 101. A program for executing this process is stored in the memory 102.
Is stored in

The image forming apparatus 1 has an operation section 6, and the operation section 6 includes buttons, a display, and the like, and is used by a user to operate the image forming apparatus 1. In this operation unit 6, the user designates a place where data to be printed exists by URL. Until this input is made, the image forming apparatus 1 waits for an input (step S).
1). In step S1, when the URL is input, the process proceeds to step S2, where 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. In this embodiment, it is assumed that the server 7 has data to be acquired.

Then, the process proceeds to step S 3, where a HEAD command for the data to be obtained is issued to the server 7. This HEAD command is
The data is transmitted to the server 7 via the interface 3 and the network 32.

The server 7 receiving this HEAD command
HEAD based on the information about the specified data
It generates format information for the command and transmits it to the image forming apparatus 1 via the network 32 and the network interface 3. Thereby, step S4
When the format information is received from the server 7, the process proceeds to step S5, and the information of "Content-type" is extracted from the format information from the server 7 and stored.

Then, the process proceeds to a step S 6, wherein a GET command for the data to be obtained is issued to the server 7. This GET command is issued to the server 7 via the network interface 3 and the network 32.

Thus, the server 7 transmits the data specified by the GET command to the image forming apparatus 1 via the network 32 and the network interface 3.
Send to

Upon receiving the reply from the server 7, the process proceeds from step S7 to step S8, where 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; otherwise, the process proceeds to step S1.
Proceed to 2. In step S10, the image processing circuit 4 is set to perform image processing for a JPEG image. That is, UC
In the R circuit 10, the UCR is set to 80%, and in the PWM circuit 11, the PWM is set to perform the PWM at a half frequency.

On the other hand, if the data is not in the JPEG format in step S9, the flow advances to step S12 to set the GIF image in the image processing circuit 4. That is, the UCR circuit 1
0 is set to UCR 100%, and the PWM circuit 11 is set to perform PWM at the frequency of the clock signal 41 as it is. After the image processing and the PWM are executed in step S10 or step S12, the image processing and the PWM are executed by the printer 5 in step S11.
An image is formed based on the M-processed image data.

As described above, an image can be formed based on the image data stored in the server 7 specified by the operation unit 6.

According to this processing, the JPEG image is converted to the UCR
Since the black component is extracted at 80%, it is possible to generate an image having an excellent connection of the gradation of the image such that the color transitions from black to another color, and performs PWM at a half frequency. Therefore, it is possible to generate an image having excellent image gradation.

For GIF images, UCR100
%, The black component is extracted, so that the light gray image is formed only with the black toner, and the gray, which is a problem in the image generated by combining C, M, Y, and K, is not gray due to pure black. Can be avoided.

Further, PWM is the clock signal 4 supplied.
Since the frequency is the same as that of No. 1, a high-resolution image in which jaggies are not noticeable can be formed.

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

The specific effects of the first embodiment are as follows. Since the storage position of the data to be acquired is specified in the operation unit 6 of the image forming apparatus 1, the image processing and the image forming processing can be performed only by the image forming apparatus 1, and another client apparatus is not required. Since the storage position of the data to be acquired is specified in the connection unit 6 of the image forming apparatus 1, communication software can be simplified, and development of the software becomes easy. -Since the server inquires "Contents-type" and judges the format of the image based on the result, it is possible to print normally even if there is no URL extension.

[Second Embodiment] In the second embodiment, desired data is acquired by the HTTP protocol based on a URL input by another device connected to the network 30, and the acquired data is acquired. An image forming apparatus that generates image data based on the image data to form an image will be described.

In the second embodiment, the position information in which the data to be obtained is stored is input as a URL from the client device 24 connected to the network 30,
The input URL information is transmitted to the image forming apparatus 1, and the image forming apparatus 1 having received the information acquires data from the server 7 and forms an image.

FIG. 5 is a block diagram showing the configuration of the entire network system including the image forming apparatus 1 according to the second embodiment of the present invention. Portions common to those in FIG. Omitted.

In FIG. 5, reference numeral 24 denotes a client device having a function of designating data to be obtained and formed by the image forming apparatus 1. An image processing circuit 4a basically performs substantially the same function as that of the above-described image processing circuit 4, and the configuration thereof will be described later with reference to FIG. Reference numeral 5a denotes a printer, the details of which will be described in detail with reference to FIG.

FIG. 6 shows an image processing circuit 4 according to the second embodiment.
In the block diagram showing the configuration of FIG. 2A, portions common to FIG. 2 described above are denoted by the same reference numerals.

In FIG. 6, reference numeral 8 denotes a DMA data transfer circuit for controlling DMA transfer of image data from the image memory 2;
Reference numeral 25 denotes a gamma conversion circuit that performs gamma conversion, and reference numeral 26 denotes a binarization circuit that binarizes input image data to generate binary data. 45 is an R data signal indicating data of a red component of the image data, 46 is a G data signal indicating data of a green component of the image data, 47 is a B data signal indicating data of a blue component of the image data, 48 is R data signal converted by the gamma conversion circuit 25, 4
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. 39 is a color selection signal for selecting a color for image formation, 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 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, first, the CPU 101
The address of the image memory 2 where the R, G, and B image data are held and the size of the data to be transferred are set for the MA data transfer circuit 8. Thereafter, the DMA data transfer circuit 8 sets the print data of In synchronization with the operation, the R, G, and B image data are sequentially read from the image memory 2 by DMA, and the read data is sent to the gamma conversion circuit 25 by the R data signal 45, the G data signal 46, and the B data. It is output as a signal 47. This output is performed by synchronizing R, G, and B data. That is, R, G, and B data of each pixel are output simultaneously.

The R data signal 45, the G data signal 46, and the B data signal 4 input to the gamma conversion circuit 25 in this manner.
7 is gamma-converted based on a preset gamma conversion table, and the R data signal 45 to the R data signal 4
8. A G data signal 49 is generated from the G data signal 46, and a B data signal 50 is generated and output from the B data signal 47, respectively. 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 to output based on the color selection signal signal 39, and determines which binarization method to use for binarization based on the binarization method selection signal 51. decide. In the second embodiment, it is assumed that the binarization circuit 26 can select either a dither method or 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 binarization pattern expressing a density corresponding to the luminance as an area gradation, and an image is formed. This is a method for generating data for use. This dithering method is a binarization method suitable for printing in which the transition between gradations is small and the boundaries between regions are clear, such as illustrations, figures, and characters.

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

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

FIG. 7 is a block diagram showing the structure of a printer 5a according to the second embodiment. Portions common to those in FIG. 3 are denoted by the same reference numerals.

In FIG. 7, 27 is an LED drive signal 52
LED array where each element emits light according to
A developing device in which a latent image is formed by turning on each element of the array and an image is formed by adsorbing toner on the latent image;
Reference numeral denotes a revolver that holds the toner cartridges of C, M, Y, and K 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, 21 is a sheet adsorbing, and the toner of the developing device is put on the sheet. A transfer drum 22 for transferring toner; a fixing drum 22 for fixing toner on the paper; a paper feed cassette 23 for holding the paper and feeding the paper during image formation;
Reference numeral 4 denotes a paper transport path.

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

When forming an image, first, the sheet cassette 2
3 is fed, and the paper is transported to a paper transport path 4.
4 is conveyed, is attracted to the transfer drum 21, and adheres to the surface of the transfer drum 21. The transfer drum 21 rotates at a constant speed, and the sheet also moves according to the rotation of the transfer drum 21. When printing is performed by the printer 5a, LE
The D drive signal 52 is supplied from the image processing circuit 4. The supplied LED drive signal 52 is any one of C, M, Y, and K image signals generated by the binarization processing of the binarization circuit 26, and the C image signal is input first.

The LED array 12 has LEDs of a width corresponding to the width of the developing device 15 arranged linearly.
Is the size of the width of one pixel. When the LED drive signal 52 supplies image data for one scanning line to be developed, a latent image for one scanning line is formed by light emission of the LED. The LED in the portion where the LED drive signal 52 is ON is turned on and the potential of the developing device 15 is high, and the portion other than that is not turned on, so that the potential of the developing device 15 is lowered and a latent image is formed.

The latent image thus formed on the developing unit 15 is firstly stored in a portion where the developing unit 15 is in contact with a C toner cartridge 17 previously disposed at a portion where the revolver 16 and the developing unit 15 are in contact. , The negatively charged cyan toner stored in the container comes into contact with the toner. The cyan toner is developed by being attracted to only the laser-irradiated portion of the developing device by an electric attraction force. The portion of the developing device 15 to which the toner is adsorbed moves to a portion in contact with the transfer drum 21 by the rotation of the developing device 15. In a portion where the transfer drum 21 and the developing device 15 are in contact with each other, the toner adsorbed on the developing device 15 is transferred onto the sheet adsorbed on the transfer drum 21.

Thereafter, the revolver 16 is rotated by １ ／ of the entire circumference so that the M toner cartridge 18 contacts the developing device 15. Then, an M image signal is input to the laser drive signal 42, and magenta toner is transferred onto a sheet in the same manner as in the development of C. At the time of development of each color, the color selection signal 39 is set so that the image data of C is output to the LED drive signal 52 at the time of development of C, and the image data of M, Y, and K is developed at the time of development of M, Y, and K, respectively. Is set to be output to the LED drive signal 52. Similarly, Y, K
Is also performed, and the toner of each color of C, M, Y, and K is 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 drums 22 through the sheet transport path 44. At this time, the toner image heated and pressed by the fixing drum 22 and transferred onto the paper is fixed on the paper and discharged out of the printer 5a. FIG. 8 is a flowchart showing processing in the image forming apparatus 1 according to the second embodiment in which printing is executed in this manner. A control program for executing this processing is stored in the memory 102.

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

The user of the client device 24 checks the U
After inputting the RL, the input URL is transmitted to the image forming apparatus 1 via the network 30. The URL transmitted in this manner is transmitted to the network 32, the network
The image is received by the image forming apparatus 1 via the interface 3. Until this input is made, the image forming apparatus 1 waits for an input (step S21). Step S21
When the URL is input, the process proceeds to step S22, where 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. . In the second embodiment,
It is assumed that the server 7 has data to be acquired.

Then, the flow advances to step S23 to issue a GET command to the server 7 for the data to be obtained. This GET command is issued to the server 7 via the network interface 3 and the network 32.

Thus, the server 7 transmits the data specified by the GET command 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 manner, the process proceeds from step S24 to step S25, where 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 S26,
The extension of the URL analyzed in step 22 is ", JPG" or ".jpe
g ”or other JPEG image.
If it is a PEG image, the process proceeds to step S27, where image processing for a JPEG image is set in the image processing circuit 4a. That is, the gamma conversion circuit 9 sets a gamma table for a natural image, and the binarization circuit 10 sets a binarization method using an error diffusion method.

On the other hand, if the format is not the JPEG format in step S26, the process proceeds to step S29, where the image processing circuit 4
The setting for the GIF image is performed for a. That is, the gamma conversion circuit 9 sets a gamma conversion table for illustration, and the binarization circuit 10 sets a binarization method using a dither method. After the image processing and the binarization processing are performed in step S27 or step S29 in this manner, step S27 is performed.
The program proceeds to step 28, where the printer 5a executes image formation based on the image data subjected to the image processing and the binarization processing. In this manner, the process of forming an image based on the data stored on the server 7 designated by the client device 24 is completed.

According to this processing, the JPEG image is subjected to gamma conversion for a natural image and further binarized by an error diffusion method, so that an image is formed with a tint and binarization suitable for a natural image. It is possible.

Further, gamma conversion for illustration is performed on the GIF image, and further binarized by the dither method. Therefore, it is possible to form an image with tint and binarization suitable for the illustration. is there.

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

The effects specific to the second embodiment are as follows. In the client device, an operation unit that can specify an address where desired data is stored and an operation unit that specifies the address in the image forming apparatus 1 are not required, and cost can be reduced. -Appropriate binarization processing according to the type of image is possible. -To determine the type of image based on the extension of the URL,
The present invention is also applicable to protocols other than the HTTP protocol.

In the above description, the first and second embodiments are described independently, but the present invention is not limited to this. For example, the program 5a of the second embodiment may be used.
May be adopted in the first embodiment. Embodiment 1
Is an image processing circuit 4a according to the second embodiment.
And the image processing circuits 4 and 4a
May include not all of the image processing functions shown in FIGS. 2 and 6 but only some of them.

The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, and the like), and can be applied to a single device (for example, a copier, a facsimile). Device).

Further, an object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and 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 implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

Examples of the storage medium for supplying the program code include a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, and CD.
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, 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. ) Performs part 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 into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instructions of the program code, The case where the CPU of the function expansion board or the function expansion unit performs part or all of the actual processing, and the function of the above-described embodiment is realized by the processing.

[0101]

As described above, according to the present invention, an address at which desired image data is stored is designated, desired data is read from the designated address to form an image, and the image data is read. An image can be formed by performing image processing according to the type of the image.

According to the present invention, desired data can be fetched from a network address designated by a user's operation via a network, and image processing can be performed in accordance with the fetched data to form an image.

According to the present invention, desired data is fetched via a network from a network address specified by a client device connected to the network, and image processing is performed in accordance with the fetched data to form an image. There is an effect that can be.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating 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 illustrating a configuration of the printer according to the first embodiment.

FIG. 4 is a flowchart illustrating processing in the image forming apparatus according to the first embodiment of the present invention.

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

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

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

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

Claims (18)

[Claims] An image forming apparatus that is connected to a network and forms an image based on image data obtained from the network, comprising: input means for inputting information related to image data; and information input by the input means. Issuing means for issuing an image request to the network on the basis of: a storage means for storing image data transmitted in response to the image request by the issuing means; and a type of image data stored in the storage means An image forming apparatus comprising: an image processing unit that controls image processing corresponding to the image processing to be executed; and an image forming unit that forms an image based on image data processed by the image processing unit. 2. The image forming apparatus according to claim 1, wherein the issuing unit issues an image request by a URL. 3. The server according to claim 1, further comprising a server storing the image data and connected to the network, wherein the issuing unit issues a URL including an address of the server. Image forming apparatus. 4. The image processing device according to claim 1, wherein the image processing unit changes image processing on the image data based on whether an image requires gradation or an image requiring resolution. 4. The image forming apparatus according to claim 3. 5. The image forming apparatus according to claim 1, wherein the input unit is an operation panel provided on the image forming apparatus. 6. The image forming apparatus according to claim 1, wherein the input unit is an interface unit for inputting a command input from a computer device connected to the network via the network. . 7. The image processing apparatus according to claim 1, wherein the image processing unit determines a characteristic of the image data based on an extension included in a file name of the image data. Image forming apparatus. 8. The image forming apparatus according to claim 3, wherein the image processing unit determines a characteristic of the image data based on a response from the server. 9. The image processing apparatus according to claim 1, wherein the image processing includes at least one of LOG conversion processing, undercolor removal processing, pulse width modulation processing, gamma conversion, and binarization processing. 2. The image forming apparatus according to claim 1. 10. An image processing method in an image forming apparatus connected to a network and performing image formation based on image data obtained from the network, wherein: an input step of inputting information related to image data; An issuing step of issuing an image request to the network based on the input information; a storing step of storing image data transmitted in response to the image request in the issuing step in a memory; An image processing step of controlling to execute image processing corresponding to the type of the image data, and an image forming step of forming an image based on the image data processed in the image processing step. Image processing method. 11. The image processing method according to claim 10, wherein in the issuing step, an image request is issued by a URL. 12. The image according to claim 10, wherein the image data is stored in a server connected to the network, and in the issuing step, a URL including an address of the server is issued. Processing method. 13. The image processing step according to claim 10, wherein the image processing for the image data is changed based on whether an image requires gradation or an image requiring resolution. 13. The image processing method according to any one of the above items 12. 14. The image processing method according to claim 10, wherein in the inputting step, data is input from an operation panel provided in the image forming apparatus. 15. The image processing method according to claim 10, wherein in the inputting step, a command input by a computer device connected to the network is input via the network. 16. The image processing method according to claim 10, wherein the characteristic of the image data is determined based on an extension included in a file name of the image data. Image processing method. 17. The image processing method according to claim 12, wherein in the image processing step, characteristics of the image data are determined based on a response from the server. 18. The image processing method according to claim 10, wherein the image processing includes at least one of LOG conversion processing, undercolor removal processing, pulse width modulation processing, gamma conversion, and binarization processing. Item 2. The image processing method according to item 1.