JPH10224526A - Image processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing system of high productivity capable of reading original images by one digital copying machine and outputting the copy of the read original images by the plural digital copying machines in real time. SOLUTION: In this image processing system constituted so as to mutually transfer image data by connecting the two digital copying machines 1(A) and 1(B), the digital copying machine on a transmission side outputs the image data to a transmission line 2 along with clocks synchronized with transfer data and line synchronizing signals for indicating the head of a line unit in a raster form while forming images on recording paper in an image formation part. The digital copying machine on a reception side writes and reads the image data received through a cable 2 to an image memory, and at the time, starts read after prescribed read start waiting time from write start and parallelly executes the write and read in a time division manner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing system capable of connecting at least two image processing apparatuses for outputting image information to a recording medium for digitally processing the image information and mutually transferring and processing the image data. It is about improvement.

[0002]

2. Description of the Related Art In recent years, digital copiers have been widely used, and accordingly, processing and editing using an image memory have been actively performed on copiers. The processing and editing functions of the digital copying machine include, for example, image rotation by address operation when reading image memory, image repeat by forming a plurality of data of the same pattern on image memory, and address when writing to image memory. Aggregation, in which a plurality of originals are copied onto one transfer sheet by an operation, and the like. To realize such a function,
A digital copying machine generally has an image memory capable of developing image data for at least one document. Some digital copiers in recent years have a function of transmitting and receiving image data to and from another digital copier via a communication cable. According to this type of digital copying machine, for example, by connecting two digital copying machines to each other, if one of the copying machines is performing a copying process and the other is not used, The image data can be transferred from one to the other, and the copying process can be shared between the two copying machines, and a large amount of copying can be performed efficiently.

[0003]

Conventionally, as described above, 2
When copying by connecting two digital copiers,
The copying machine on the receiving side does not output the copy immediately after receiving the data of the first copy, but temporarily stores the data in the image memory, and copies and outputs the first copy when the transmitting side performs the copy output of the second copy. In such a case, the timing of copy output on the receiving side is delayed with respect to the transmitting side. The reason is that usually, in a digital copying machine, the reading of a document image by a scanner is synchronized with a plotting cycle of a plotter (a polygon motor synchronization signal that changes by rotation of a polygon motor in writing using a semiconductor laser in an electrophotographic process). In order to transfer the read image data in raster format to the subsequent image processing unit and plotter based on the line synchronization signal, when two digital copying machines are connected as described above, one digital copying machine is used. This is because it is difficult to copy and output data read by the scanner from the plotters of both digital copying machines in real time. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems of the related art, and a document image is read by one image forming apparatus, and a copy of the read document image is output by a plurality of image forming apparatuses in real time. It is an object of the present invention to provide a highly productive image processing system capable of performing image processing.

[0004]

According to a first aspect of the present invention, at least two image processing apparatuses having an image forming unit capable of outputting image data to a recording medium are transmitted. In an image processing system that is connected to each other via a line and configured to be able to transfer image data to each other, the image processing apparatus on the transmission side performs image formation on a recording medium by an image forming unit, and transmits the image data. An image data transmitting means for outputting to a transmission line together with a line synchronization signal indicating a head of a line unit in a raster format and a clock synchronized with transfer data, the image processing device on the receiving side includes an image memory for storing image data, Writing and reading the image data received via the transmission line to and from the image memory, and reading out the data after a predetermined reading start waiting time from the start of writing. And a memory control unit that executes writing and reading in parallel in a time-division manner, so that copies of the original image read by one image forming apparatus are apparently Copy output in real time. Also,
According to a second aspect of the present invention, in the image processing system according to the first aspect, the image processing apparatus on the receiving side samples and measures an interval of the received line synchronization signal, and determines a line writing interval of its own image forming unit. In view of the above, by providing the read start wait time calculating means for calculating the read start wait time, even when the line interval of the image data sent from the transmitting side is unknown, real-time copy output by the received data can be performed. Made it possible. According to a third aspect of the present invention, at least two image processing apparatuses having an image forming unit capable of outputting image data to a recording medium are connected to each other via a transmission line, and the image data can be mutually transferred. In the image processing system configured as described above, the image processing device on the transmission side performs image formation on the recording medium by the image forming unit,
Image data transmitting means for outputting the image data to a transmission line together with a line synchronization signal indicating the head of a line unit in a raster format and a clock synchronized with the transfer data; A pair of image memories for storing data, and storing the image data received via the transmission line in one of the image memories. After the storage is completed, the image data is read from the image memory and output to the image forming unit, and transmitted. Memory control means for storing the image data received next via the line in the other image memory, and the provision of a plurality of image forming means that a copy of the original image read by one image forming apparatus is apparently provided. Copy output from the device in real time is now possible. According to a fourth aspect of the present invention, in the image processing system according to the first or third aspect, a function of detecting a transfer error of image data in a line unit or a page unit is provided.
Improving reliability by enabling early detection of sudden transmission line disconnection, etc. According to a fifth aspect of the present invention, in the image processing system according to the first or third aspect, by providing a function of compressing and transferring image data, the time and cost required for data transfer can be reduced. By reducing the transfer rate, the occurrence of transfer errors has been reduced and reliability has been improved.

[0005]

Embodiments of the present invention will be described below. FIG. 1 is a system configuration diagram showing an example of an embodiment of an image processing system according to the present invention. Two digital copiers 1 (A) and 1 (B) of the same type are connected to a communication cable (transmission line). 1 shows an example of a system configuration connected to each other via a network. FIG. 2 is a conceptual diagram showing the configuration of the digital copiers 1 (A) and 1 (B) constituting the image processing system, and each digital copier 1 (A) and 1 (B).
A reading unit 10 for reading an image on a document;
And an image forming unit 20 that prints out an image read by the printer on recording paper. The reading unit 10 exposes an image of a document D set on the document table 3 by an exposure lamp 4 extending in a main scanning direction movable in a sub-scanning direction along the document table 3, and sequentially reflects the reflected light on a mirror. The light is reflected by 5 and made incident on a CCD (image sensor) 6. CCD6
Converts photoelectrically the incident light and outputs it to an IPU (image processing unit) 7 as an electric signal corresponding to the intensity of the light. The IPU 7 performs processing such as shading correction on the signal from the CCD 6, and then A / D converts the signal into an 8-bit digital signal, and further performs image processing such as scaling processing and dither processing to generate image data. Along with the image synchronization signal PCLK (see FIG. 3).
Send to 3. The scanner control unit 9 controls the drive motor and the like while detecting the drive state of each unit of the reading unit 10 by various sensors to execute the above process.
Various parameters are set for the IPU 7.

In the image forming section 20, a semiconductor laser 21 in the writing section 13 is modulated and driven in accordance with image data from the reading section 10, and a laser beam from the semiconductor laser 21 is rotated by a polygon mirror 22 rotating at a constant speed. The light is reflected and irradiated on the surface of the photosensitive drum 12. Polygon mirror 22
Scans the laser beam in a direction perpendicular to the rotation direction of the photosensitive drum 12. By irradiating the surface of the photosensitive drum 12 uniformly charged by the charging charger 11 with the laser light, an electrostatic latent image is formed on the surface of the photosensitive drum 12, and the electrostatic latent image is formed by the developing device 14 with toner. By developing, a visualized toner image is obtained. Then, the transfer paper 17 that has been fed in advance from the paper feed tray 18 by the paper feed roller 16 and has been in contact with the registration roller 17 and is on standby is conveyed at a timing with the photosensitive drum 12, and is transferred. Thus, the toner image on the photosensitive drum 12 is electrostatically transferred to the transfer paper P, and the transfer paper P is separated from the photosensitive drum 12 by the separation charger 23. Thereafter, the toner image on the transfer paper P is fixed by heating by the fixing device 24, and is discharged to the discharge tray 26 by the discharge roller 25. On the other hand, after the electrostatic transfer, the toner remaining on the photosensitive drum 12 is removed by the cleaning device 2.
6, the photosensitive drum 12 is discharged by the discharge charger 27. The plotter control unit 28 controls the polygon motor 29 for driving the polygon mirror 22 and other driving motors while detecting the driving state of each unit of the image forming unit 20 by various sensors in order to execute the above process. I do.

Here, the relationship between the image synchronization signal PCLK output from the IPU 7 of the reading unit 10 and other signals will be described with reference to FIG. Frame gate signal (/ FGA
TE) is a signal indicating an image effective range for an image area in the sub-scanning direction, and image data is valid while this signal is at a low level (low active). Also, this / F
GATE is asserted or negated at the falling edge of the line synchronization signal (/ LSYNC). / LS
YNC is asserted for a predetermined number of clocks at the rising edge of the pixel synchronization signal (PCLK), and after the rising of this signal, the image data in the main scanning direction becomes valid after a predetermined clock. The image data is sent at a rate of one for one cycle of PCLK. The read range L in the main scanning direction shown in FIG. Is sent out as raster format data. The effective sub-scanning range of image data is usually determined by the size of the transfer paper.

The system control unit 30 detects an input state of the operation unit 31 by the operator, and sets various parameters of the reading unit 10, the storage unit 32, and the image forming unit 20, and executes a process execution instruction through communication. Also, the system control unit 3
0 causes the state of the entire system to be displayed on the display screen of the operation unit 31. An instruction to the system control unit 30 is given by an operator operating keys on the operation unit 31. The system control unit 30 controls the transmission / reception unit 33 to communicate with the other digital copying machine. The transmission / reception unit 33 is mutually connected to the transmission / reception unit of the other digital copying machine via the communication cable 2, and transmits control data and image data from the system control unit 30 to the other digital copying machine via the communication cable 2. Control data, image data, and the like transmitted through the communication cable 2. The selector unit 34 changes the internal connection state in accordance with an instruction from the system control unit 30 to switch the supply source of the image data for forming an image to one of the reading unit 10 and the storage unit 32, and The source of the data stored in the memory 32 is switched to one of the reading unit 10 and the transmitting / receiving unit 33. The storage unit 32 can store image data corresponding to one document, and usually stores image data from the IPU 7. It is used to realize various functions such as image rotation and image repeat. The control of data writing and reading at that time is performed by the system control unit 30.

FIG. 4 shows the internal configuration of the storage unit 32. As shown, the storage unit 32 includes an image memory 35, a pixel synchronization signal generation unit 36, a line synchronization signal generation unit 37, a line synchronization signal counting unit 38, selectors 39-1 and 39-2, a memory control unit 40, and the like. Be composed. The image memory 35 is for storing image data, is composed of a storage element such as a DRAM, and has a total memory capacity of 4 Mbytes.
The input image data is stored under the control of the memory control unit 40. The pixel synchronization signal generator 36 is configured by an oscillation circuit, and outputs a clock signal of a predetermined frequency. The line synchronization signal generator 37 is configured by a logic circuit including a TTL circuit and the like, and generates and outputs a line synchronization signal from the polygon motor synchronization signal from the image forming unit 20. The line synchronization signal counting unit 37 is configured by a counter logic circuit including a TTL circuit and the like, and samples an interval of an externally input line synchronization signal. The information is read by the MPU of the memory control unit 40 via the CPU bus. The selector 39-1 is a selector for selecting a pixel synchronization signal. It is constituted by a TTL gate, and selects one of the pixel synchronization signal from the pixel synchronization signal generator 36 and the input pixel synchronization signal in accordance with an instruction signal from the memory controller 40. The selector 39-2 is a selector for selecting an output line synchronization signal. It is constituted by a TTL gate, and selects one of a line synchronization signal from the line synchronization signal generator 37 and an input line synchronization signal in accordance with an instruction signal from the memory controller 40.

FIG. 5 is a block diagram of the memory control unit 40.
The memory control unit 40 includes a plurality of functional blocks 4 including an MPU.
1 to 47. Each functional block 41-47
Is composed of a logic circuit. The MPU 41 communicates with the system control unit 30, receives a command, and sets an operation setting corresponding to the command to the other functional blocks 42 to 47.
And sends status information for notifying the state of the storage unit 32 to the system control unit 30. The input data processing unit 42 captures 1-bit input image data together with an input image synchronization signal, packs the data into an 8-bit data width, and outputs the data to the image data bus 60. Also,
Since the input clock is different from the internal operation clock, the input image data is synchronized. Conversely, the output data processing unit 43 takes in the image data from the image data bus 60 with a data width of 8 bits, performs parallel / serial conversion, and outputs it as 1-bit output image data together with the output image synchronization signal. Further, since the output clock is different from the internal operation clock, the output image data is synchronized with the output clock. The arbiter 44 arbitrates for access request signals from the input data processing unit 42 and the output data processing unit 43. The input image address counter 45 includes a counter that counts up with an access permission signal. The configuration of the output image address counter 46 is the same as that of the input image address counter 45. The address selector 47 selects a read or write address according to a selection signal from the arbiter 44, and divides the selected address into a row address and a column address corresponding to a DRAM which is an image memory, and divides the selected address into a 11-bit image address bus. And output to the control signal line 61. The access control circuit 48, according to the access permission signal,
An M control signal (RAS, CAS, WE) is output to the image address bus and control signal line 61.

The operation of the image processing system configured as described above will be described below. Here, one digital copying machine 1 (A) constituting the image processing system shown in FIG. 1 is a transmitting side (hereinafter, referred to as A machine), and the other digital copying machine 1 (B) is a receiving side (hereinafter, referred to as A machine). The description will be made on the assumption that this is referred to as "machine B." In the following description, (A) and (B) attached after the reference numerals of the respective constituent elements indicate the units A and B, respectively.
Indicates a component of the machine. When a plurality of copies are taken by the machine A and the machine B is not used, a request for image transfer and image copy output is sent from the system controller 30 (A) of the machine A to the system controller 30 (B) of the machine B. Done. Upon receiving the request from the A machine, the B machine confirms that the copying machine is not currently executing the copy process, and then returns permission to the A machine. At this time, the machine A transmits the information on the image size in the main and sub directions to be transmitted to the machine B by communication in advance. Thereafter, the original set on the original platen 3 (A) of the machine A is read by the above-described reading process, and the image forming unit 20 (A) forms a copy image of the first original in real time. At this time, A
The storage unit 32 (A) of the machine stores the image data from the reading unit 10 (A) in the image memory 35 for forming the second and subsequent images. The image data (including the first sheet) from the reading unit 10 (A) is transferred from the transmission / reception unit 33 to the machine B via the communication cable 2. Storage unit 32 of Aircraft-B
(B), after receiving the image input command from the system control unit 30 (B), the communication cable 2 and the transmission / reception unit 33
An input memory access request signal is generated for the image data input through (B), and storage in the image memory 35 (B) is started.

FIG. 6 is a timing chart of the input processing and the output processing operation in the memory control unit 40 (B) of the machine B. As shown in the drawing, the memory control unit 40 (B) starts image output processing after a reading start waiting time T from the start of input processing. The image output command is issued from the system control unit 30 (B) to the storage unit 32 (B). The read start waiting time T is calculated and set in advance for each model of the digital copying machine in consideration of the worst case of the rotation variation of the polygon motor 29. That is, the set values of the read start waiting time T of the same type of digital copying machine are the same. This read start waiting time T is
It is desired that the read address m from the image memory 35 (B) be a value that does not overtake the write address n. However, the read start waiting time T is on the order of several tens of msec, and is negligible compared to the time required for input / output of the entire image. Therefore, an image is output in real time from the viewpoint of the operator.

As shown in FIG. 6, the access to the image memory 35 (B) is performed in a time period which is half of the cycle time of the input memory access request signal and half the cycle time of the input memory access request signal. The cycle of the clock signal for operating the access control circuit 48 (B) is set in FIG. Therefore, by reading and writing the memory in a time-division manner, the storage unit 32 (B) can execute image input and output in parallel. Further, the line synchronization signal counting unit 38, which is a circuit for sampling the input line synchronization signal with its own clock and calculating the assertion interval, is provided in the storage unit 32. However, since the system control unit 30 calculates the read start waiting time from the relationship with its own write cycle, it is possible to output images in real time.
FIG. 7 shows another example of the storage unit 32. The storage unit 32 of this embodiment is different from the storage unit 32 shown in FIG.
Further, an image memory 50 for storing image data for one page, a memory control unit 51 for controlling writing and reading of image data to and from the image memory 50, and two sources of output image data and output frame gate signals And a selector 39-3 for switching to one of the two image memories 35 and 50. That is, in this embodiment, a pair of image memories 35 and 50 capable of storing image data for one page are provided, and these are controlled by separate memory control units 40 and 51. . The two memory control units 40 and 51 are:
In cooperation with the instruction of the system control unit 30, first,
The received image data is stored in one image memory (35 or 5).
0), and after completion of the storage, while reading out the image data from the image memory (35 or 50) and outputting it to the image forming unit 29, the next received image data is stored in the other image memory (35 or 50). Remember. In this configuration, when the number of copies of the document is large, it takes time to store the image data of the first copy in the image memory (35 or 50).
The time required to store the image data of the second copy and thereafter in the image memory can overlap the time of the copy output of the first copy, so that the processing efficiency on the receiving side can be reduced without lowering the processing efficiency as compared with the normal time. Efficiency can be obtained. Also,
Although two memory control units are required, since there is no need to perform complicated timing control as shown in FIG. 6, each memory control unit can be configured more simply than the above case. FIG. 8 shows another embodiment of the transmitting and receiving unit 33.
The transmission part of the transmission / reception part 33 is provided with a transfer error code addition part 55 for adding a code which is the sum data obtained by adding the transmission data to be transmitted last for each line. A transfer error detection unit 56 for judging the code and comparing the sum of the data transferred to one line is provided. By adopting such a configuration, a transfer error of image data can be detected in a line unit or a page unit, so that a sudden disconnection of the communication cable 2 or the like can be detected at an early stage, and reliability can be improved. Can be improved.
FIG. 9 shows still another embodiment of the transmission / reception unit 33. The transmission unit of the transmission / reception unit 33 compresses (encodes) image data to be transmitted in line units. A data compression section 57 is provided, and a data expansion section 58 for expanding (decoding) compressed and sent image data is provided at a receiving portion. By employing such a configuration, the amount of image data to be transmitted can be reduced, so that the time and cost required for data transfer can be reduced, and the occurrence of transfer errors can be reduced and reliability can be improved. . In the above embodiment, an example of the configuration of an image processing system in which two digital copying machines are connected has been described. However, a system configuration in which a larger number of digital copying machines are connected may be used.
In the embodiment shown in FIG. 7, two image memories each capable of storing one page of image data are shown. However, three or more image memories are provided, and a memory control unit and a selector corresponding thereto are provided. Is added, a system with higher processing efficiency can be realized.

[0014]

As described above, according to the present invention, the following excellent effects can be exhibited. According to the image processing system of the present invention, a copy of a document image read by one image forming apparatus can be apparently simultaneously copied and output from a plurality of image forming apparatuses in real time, and the image forming apparatus receiving image data Since the processing efficiency of the apparatus is not lowered than usual, the processing efficiency can be significantly improved. According to the image processing system of the second aspect, in addition to the first aspect, even when the line interval of the image data sent from the transmission side is unknown, the copy output can be performed in real time by the received image data. Therefore, the present invention can be flexibly applied to a system in which two or more image forming apparatuses of different types are connected. According to the image processing system of the third aspect, a copy of the original image read by one image forming apparatus can be apparently copied from a plurality of image forming apparatuses at the same time in real time, and a plurality of originals can be read. In this case, the time for storing the second and subsequent image data in the image memory can be overlapped with the time for copying and outputting the first image without reducing the processing efficiency of the receiving side as compared with the normal time. , High processing efficiency can be obtained. Further, according to the image processing system of the fourth aspect, in addition to the first or third aspect, by providing a function of detecting an image data transfer error in units of lines or pages, it is possible to prevent a sudden disconnection of a transmission line or the like. Early detection is possible and reliability can be improved. According to the image processing system of the fifth aspect, in addition to the first or third aspect, by providing a function of compressing and transferring image data, the time and cost required for data transfer can be reduced and the transfer rate can be reduced. By lowering the value, the occurrence of transfer errors can be reduced and reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an example of an embodiment of an image processing system according to the present invention.

FIG. 2 is a conceptual diagram showing the configuration of a digital copying machine that constitutes the system shown in FIG.

FIG. 3 is an image synchronization signal P output from an IPU (Image Processing Unit) of a reading unit of the digital copying machine.
FIG. 6 is a timing chart showing the relationship between CLK and other signals.

FIG. 4 is a block diagram showing an internal configuration of a storage unit in FIG. 2;

FIG. 5 is a block diagram showing an internal configuration of a memory control unit in FIG. 4;

FIG. 6 is a timing chart of an input processing and an output processing operation in the memory control unit of the digital copying machine on the receiving side.

FIG. 7 is a block diagram showing another embodiment of the storage unit.

FIG. 8 is a block diagram showing another embodiment of the transmission / reception unit.

FIG. 9 is a block diagram showing still another embodiment of the transmission / reception unit.

[Explanation of symbols]

1 (A), 1 (B) Digital copier (image forming apparatus), 2 communication cable (transmission line), 3 platen, 4
Exposure lamp, 6 CCD, 7 IPU, 9 Scanner control section, 10 Reading section, 11 Charger, 12
Photoconductor drum, 13 writing unit, 14 developing device, 19 transfer charger, 20 image forming unit, 21 semiconductor laser,
22 Polygon mirror, 23 Separate charger, 28
Plotter control unit, 30 system control unit, 31 operation unit, 32 storage unit, 33 transmission / reception unit, 34 selector unit, 35 image memory, 36 pixel synchronization signal generation unit, 3
7 line synchronization signal generation section, 38 line synchronization signal counting section, 39-1 selector, 39-2 selector, 39-3
Selector, 40 memory control unit, 41 MPU, 42
Input data processing unit, 43 output data processing unit, 44 arbiter, 45 input image address counter, 46 output image address counter, 47 address selector, 48
Access control circuit, 50 image memory, 51 memory control unit, 55 transfer error code addition unit, 56 transfer error detection unit, 57 data compression unit, 58 data decompression unit, 60
Image data bus, D original, P transfer paper.

Claims (5)

[Claims] 1. An image processing apparatus wherein at least two image processing apparatuses each having an image forming unit capable of outputting image data to a recording medium are connected to each other via a transmission line so that the image data can be mutually transferred. In the system, the image processing apparatus on the transmission side forms an image on a recording medium by the image forming unit and transmits the image data in a raster format together with a line synchronization signal indicating a head of a line unit and a clock synchronized with the transfer data. Image data transmitting means for outputting the image data to a line, the image processing device on the receiving side performs writing and reading of the image memory for storing the image data and the image data received via the transmission line to and from the image memory. At this time, reading is started after a predetermined reading start waiting time from the start of writing, and writing and reading are executed in parallel in a time-division manner. Image processing system comprising: the memory control means. 2. The image processing apparatus on the receiving side samples and measures the interval of the received line synchronization signal, and calculates the read start waiting time from the relationship with the line writing interval of its own image forming unit. The image processing system according to claim 1, further comprising a reading start waiting time calculating unit. 3. An image processing apparatus wherein at least two image processing apparatuses each having an image forming unit capable of outputting image data to a recording medium are connected to each other via a transmission line so that the image data can be mutually transferred. In the system, the image processing apparatus on the transmission side forms an image on a recording medium by the image forming unit and transmits the image data in a raster format together with a line synchronization signal indicating a head of a line unit and a clock synchronized with the transfer data. Image data transmitting means for outputting the image data to a line, the image processing device on the receiving side stores the image data received via the transmission line in one image memory, and a pair of image memories each storing one image data. After the storage, the image data is read from the image memory and output to the image forming unit, and the next image data received via the transmission line is stored in the other image memory. A memory control means for storing the,
An image processing system comprising: 4. The image processing system according to claim 1, further comprising a function of detecting an image data transfer error in line units or page units. 5. The image processing system according to claim 1, further comprising a function of compressing and transferring image data.