JP3903464B2 - Image forming apparatus, image signal input processing method and output processing method - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
Image reading means or digital image input means, and image data obtained by converting the image signal read by the reading means into a digital signal, or a large capacity such as a semiconductor memory and a hard disk drive for storing image data input from the digital image input means The present invention relates to a technology for managing and controlling data transfer start timing in a device composed of the above-described storage devices, and resource occupancy timing of semiconductor memory and mass storage devices.
[0002]
[Prior art]
In recent years, with the progress of digitization of copiers, processing and editing using image memory has become popular. Among them, there is a function called electronic sorting that stores image data for a plurality of originals in a memory, and copies and outputs a specified number of copies collectively to reduce sorting work. In order to store multiple image data, storing the image data as it is in the semiconductor memory requires a memory equivalent to the amount of data for the number of stored images, and the following method is generally used because the memory cost becomes enormous. Used.
1. A secondary storage device such as a hard disk, which is cheaper than a semiconductor memory, is used as a storage memory with a configuration of semiconductor memory + storage memory.
2. A semiconductor memory is used as the storage memory, the image data is compressed using compression processing, and the total amount of memory is reduced by reducing the amount of data per sheet.
3. A plurality of image input or output means (image scanner, printer controller, file server, FAX controller, etc.) share the same image memory.
[0003]
In many cases, a memory control controller (hereinafter referred to as a DMA controller) using a DMA (Direct Memory Access) data transfer system is used to input or output image data to or from an image memory. The DMA controller transfers data to a specific area of the image memory based on memory area management information called a descriptor. Data transfer is performed by dividing a memory area in which one image is stored into a plurality of descriptors. In the memory control using the DMA controller, the data transfer progress status (start, end) specified by each descriptor is notified, the data transfer execution timing control (interrupt data transfer in the middle of the image memory area, The data transfer timing of the semiconductor memory connected to the DMA controller and the large-capacity secondary storage device can be easily controlled, and the DMA technology is wide. It can be applied in the field (Japanese Patent Laid-Open No. 2000-58724, Japanese Patent Laid-Open No. 6-103225).
When a secondary storage device such as a hard disk, which is cheaper than a semiconductor memory, is used as the storage memory, a plurality of data transfers (data writing and reading processes) cannot normally be performed on a single storage device. It is common to divide a data transfer unit to a secondary storage device using a descriptor and execute this in a time-sharing manner so that a plurality of data transfer operations are executed in parallel. .
[0004]
However, when such a time-sharing process is used, the time required for data transfer is not shortened, so that the time required for inputting or outputting image data as in an image forming apparatus is minimized. In the case where the process is affected, the time-sharing process may cause a decrease in productivity. Here, the high productivity of the device means that the device functions while maintaining the maximum processing capacity (for example, processing speed). Therefore, the image data is compressed, the data transfer amount is reduced, or a secondary storage device having a high data transfer speed is installed to shorten the time required for data transfer to the secondary storage device. It was. Conventionally, the resource of the secondary storage device is not substantially synchronized with the image data input or output processing using the image input or output means without actively performing time division transfer for the purpose of simplifying the memory control. As a means to occupy and perform data transfer.
Conventionally used secondary storage devices are slower in transferring image data from the semiconductor memory to the secondary storage device than the image input / output means and the image data transfer rate to the semiconductor memory. Even if the data processing capacity of the secondary storage device is reduced by performing compression, there is no difference between the data processing speed between the image input or output means and the semiconductor memory, so that data transfer between the semiconductor memory and the secondary storage device is possible. Even if the transfer timing control of the processing (including data conversion processing such as data compression) is controlled independently and optimally, the productivity of the image forming apparatus is not improved. As described above, various attempts have been made to improve the productivity of the image forming apparatus, but there has been no effective technique.
[0005]
[Problems to be solved by the invention]
In recent high-speed machines, it is possible to read both the front and back of a document simultaneously, the processing capability of image input or output means is improved, and in order to further improve the efficiency, it is necessary to operate the document input processing of the image input device non-stop. Some models have also appeared. Therefore, not only the memory timing control after the data transfer from the image input means but also whether or not the processing can be performed based on conditions such as the current state of the memory control and the characteristics of the storage device when a processing request is made from the image input means. It has become necessary to provide a function for performing document feed stop / non-stop control switching processing on the image input device side, such as making a prediction in advance and notifying the image input means of whether or not document feed non-stop control is possible.
In addition, there are various types of image input or output means connected to the image forming apparatus, and there are cases in which many types of different processing requests occur at the same time, and a system that can cope with such cases is demanded. . For example, when a read process is performed for an A image and a write process request for a B image is generated, whether or not the B image process is possible is predicted in advance, and switching to the write process is performed. Technology is desired. In addition to this, there are also demanded techniques for improving the efficiency of switching input or output devices and preventing malfunctions.
In addition, the problem of restriction of processing time is increasing as processing speeds up and efficiency increases. For example, in FAX transmission processing, there is a rule for data transfer time in a data transfer protocol using a telephone line. If data transmission is not performed within a certain time, the telephone line is disconnected and data transfer cannot be performed. . In addition, when the color image forming apparatus has a configuration in which a color image is obtained by outputting and superimposing multiple color image data at regular intervals, the image data stored in the secondary storage device is determined. If the image is not read and output within a predetermined time, a color image cannot be formed or productivity is lowered.
In order to maximize the data processing efficiency according to the processing capability of the storage device, it is an object of the present invention to optimally control resource management and data transfer operation processing. In particular, based on the data transfer speed between the image input or output means and the storage device determined by the image input or output means connected to the image forming apparatus and the processing request time of the next image information from the input or output device, An object is to determine whether or not a process desired by a user is possible, and to realize efficient use of the apparatus and prevention of malfunction of the apparatus without changing the configuration of the apparatus.
[0006]
[Means for Solving the Problems]
  The invention of claim 1An image input unit that transports the document from the set position to the reading position, reads the document being transported and generates an image signal, an image storage unit that stores the image signal transferred from the image input unit, and an image signal And image output means for writing an image on a sheet based onIn the image forming apparatus, the image inputImage signal from the image storage means to the image storage meansMeans for setting the transfer rate;From the image input means to the image storage meansCapacity of image signal to be transferred and previousReprintLike feeding speedRollingA transfer time calculation means for calculating the time required to complete the transmission;Until the original is conveyed from the set position to the reading positionCalculate timeManuscriptDuring the transfer of the image signalImage inputWhen requested, the transfer time calculating means andManuscriptBased on the calculation result of the transport time calculation means,ManuscriptTransfer of the image signal currently being executed is completed within the time calculated by the transport time calculation means.A determination means for determining whether or not, and only when it is determined by the determination means to be completed,Said requested during transfer of image signalControl means for causing the image input means to carry a document for inputting an image.An image forming apparatus characterized by the above.
  The invention of claim 2An image input unit that reads an original and generates an image signal, an image output unit that conveys a sheet from a setting position to a writing position, and writes an image on the sheet based on the image signal, and is transferred to the image output unit Image storage means for storing image signalsIn the image forming apparatus,The transfer is completed from the means for setting the transfer speed of the image signal from the image storage means to the image output means, the capacity of the image signal transferred from the image storage means to the image output means, and the transfer speed. There is a transfer time calculation means for calculating the time required for the paper, a paper transport time calculation means for calculating the time until the paper is transported from the set position to the writing position, and an image output request is made during the transfer of the image signal. Then, based on the calculation results of the transfer time calculation means and the paper transfer time calculation means, it is determined whether or not the transfer of the currently executed image signal is completed within the time calculated by the paper transfer time calculation means. Only when it is determined to be completed by the determination means and the determination means, the image output means causes the image output means to carry the paper for the requested image output during the transfer of the image signal. And a control meansAn image forming apparatus characterized by the above.
  The invention of claim 3 is claimed in claim1In the image forming apparatus described above,The image forming apparatus stores unique device information of at least one or more image input units, and at least one or more image input units are connected to the image forming device, and the unique device information of the connected image input unit is stored. And a means for comparing the acquired and stored unique device information of the image input means with the unique device information stored in the image forming apparatus, and the determination means includes: The determination is performed only when the comparison results of the unique device information match.An image forming apparatus characterized by the above.
  The invention of claim 4 is claimed in claim2In the described image forming apparatus,The image forming apparatus stores unique device information of at least one or more image output means, and at least one or more image output means is connected to the image forming apparatus, and the unique device information of the connected image output means. And a means for comparing the acquired and stored unique device information of the image output means with the unique device information stored in the image forming apparatus, and the determination means includes: The determination is performed only when the comparison results of the unique device information match.An image forming apparatus characterized by the above.
  The invention of claim 53. The image forming apparatus according to claim 1, further comprising a selection unit for selecting whether or not to execute the determination function of the determination unit.
  The invention according to claim 6 conveys the document from the set position to the reading position, reads the document being conveyed, generates an image signal, and stores the image signal transferred from the image input unit. An image signal input processing method in an image forming apparatus having an image storage means and an image output means for writing an image on paper based on an image signal, wherein the image signal is transferred from the image input means to the image storage means The transfer is completed from the step of setting the speed, the capacity of the image signal transferred from the image input means to the image storage means, and the transfer speed. There is a transfer time calculation step for calculating the time required for the document, a document transfer time calculation step for calculating the time until the document is transported from the set position to the reading position, and an image input request during the transfer of the image signal. A determination is made as to whether or not the transfer of the currently executed image signal is completed within the time calculated in the document transport time calculation step based on the calculation results of the transfer time calculation step and the document transport time calculation step. An image signal input comprising: a determination step to be performed; and a step of conveying a document for the requested image input during the transfer of the image signal only when it is determined to be completed by the determination step It is a processing method.
  According to a seventh aspect of the present invention, there is provided an image input unit that reads a document and generates an image signal, an image output unit that conveys a sheet from a setting position to a writing position, and writes an image on the sheet based on the image signal; In an image forming apparatus having an image storage means for storing an image signal transferred to an image output meansImage signalOut ofA force processing method comprising:From the image storage means to the image output meansImage signalofSetting the transfer rate; andFrom the image storage means to the image output meansCapacity of image signal to be transferred and previousReprintLike feeding speedRollingA transfer time calculation process for calculating the time required to complete the transmission;Until the paper is transported from the set position to the writing positionCalculate timePaperDuring the transfer time calculation step and the transfer of the image signal,Image outputWhen requested, the transfer time calculation step andPaperBased on the calculation result of the transport time calculation process,PaperTransfer of the currently executed image signal is completed within the time calculated in the transport time calculation process.A determination step for determining whether or not, and only when it is determined to be completed by the determination step,During image signal transferInThe requestedFor image outputPaperofTransportI doProcess andHaveImage signal characterized byOut ofForce processing method.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Prior to describing an example of the present invention, an embodiment of an image forming apparatus to which the present invention is applied will be described by taking a digital copying machine as an example.
FIG. 1 is a block diagram showing an outline of a digital copying machine. The digital copying machine is mainly composed of a reading unit 1 and an image forming unit 2. The reading process of the reading unit 1 and the image forming process of the image forming unit 2 will be briefly described with reference to FIG.
The document 11 is scanned and exposed by an exposure lamp 13 movable along the document table 12, and the reflected light is subjected to photoelectric conversion by a CCD (image sensor) 14 to obtain an electrical signal corresponding to the intensity of the light. An IPU (image processing unit) 15 performs processing such as shading correction on the electrical signal to perform A / D conversion to obtain an 8-bit digital signal, and further performs image processing such as scaling processing and dither processing to generate an image synchronization signal. At the same time, an image signal is sent to the image forming unit 2.
FIG. 2 is a view of the document table viewed from above.
In order to execute the above process, the scanner control unit 16 performs detection of various sensors, control of a drive motor, and the like, and sets various parameters in the IPU 15. The above is the reading process.
[0008]
In the image forming unit 2, the constant-rotation photosensitive member 22 that is uniformly charged by the charging charger 21 is exposed by laser light modulated by image data from the writing unit 23. An electrostatic latent image is formed on the photoconductor 22 and developed into a toner image by developing it with toner by the developing device 24. The transfer paper that has been previously fed from the paper feed tray 26 by the paper feeding roller 25 and is waiting by the registration roller 27 is transported in time with the photoconductor 22, and the toner on the photoconductor 22 is transferred by the transfer charger 28. Electrostatic transfer is performed on the paper, and the transfer paper is separated from the photoreceptor 22 by the separation charger 29. Thereafter, the toner image on the transfer paper is heat-fixed by the fixing device 30 and discharged to a discharge tray 32 by a discharge roller 31. On the other hand, the toner image remaining on the photosensitive member 22 after electrostatic transfer is removed by pressure contact with the photosensitive member 22 by the cleaning device 33, and the photosensitive member is discharged by the discharging charger 34. The plotter control unit 35 performs detection of various sensors and control of a drive motor and the like in order to execute the above process. The above is the image forming process.
[0009]
Here, the state of the image synchronization signal output from the IPU 15 of the reading unit 1 will be described with reference to FIG. The frame gate signal (/ FGATE) represents a valid image range for an image area in the sub-scanning direction, and image data during which this signal is at a low level (low active) is valid. This / FGATE is asserted or negated at the falling edge of the line synchronization signal (/ LSYNC). / LSYNC is asserted for a predetermined number of clocks at the rising edge of the pixel synchronization signal (PCLK), and image data in the main scanning direction is validated after a predetermined clock after the rising of this signal. The transmitted image data is one for one cycle of PCLK, and is divided into 400 DPI equivalent from the arrow portion in FIG. The image data is sent out as raster format data starting from the arrow. Further, the sub-scanning effective range of image data is usually determined by the transfer paper size.
[0010]
The system control unit 3 detects the input state to the operation unit 7 by the operator, and communicates the setting of various parameters to the reading unit 1, the storage unit 4, the image forming unit 2, the FAX unit 5, process execution instructions, etc. Do. Further, the state of the entire system is displayed on the operation unit 7. An instruction to the system control unit 3 is made by key input to the operation unit 7 by the operator.
In response to an instruction from the control unit 3, the FAX unit 5 performs binary compression on the received image data based on the G3 and G4 FAX data transfer rules, and transfers the image data to the telephone line. Further, the data transferred from the telephone line to the FAX unit is restored to binary image data, which is sent to the writing unit 23 of the image forming unit 2 to be visualized.
The selector unit 6 changes the state of the selector according to an instruction from the system control unit 3, and takes in image data from any of the reading unit 1, the storage unit 4, and the FAX unit 5.
The storage unit 4 normally stores image data of a document input from the IPU 15 and is used for a copy application such as repeat copy or rotation copy. Further, it is also used as a buffer memory for temporarily storing binary image data from the FAX unit 5. These data storage instructions are given by the system control unit 3 via the memory control unit 43.
[0011]
Next, the outline of the storage unit 4 will be described, and the function will be described for each component.
The outline of the operation of the storage unit 4 is as follows.
At the time of image input and data storage, image data is written in or read out from a predetermined image area of the image memory 42 by image transfer DMAC according to an instruction from the system control unit 3. At this time, the image transfer DMAC performs transfer control while counting the number of image lines.
FIG. 4 is a block diagram of the storage unit. Hereinafter, the function will be described for each block.
4-1 Explanation of image input / output DMAC
The image input / output DMAC 41 includes a CPU and a logic LSI. Communicates with the memory control unit 43, receives a command from the memory control unit 43, sets an operation according to the command, and transmits status information to inform the memory control unit 43 of the state of the image input / output DMAC To do. When an image input command is received from the memory control unit 43, the input image data is packed as memory data in units of 8 pixels according to the input image synchronization signal, and is output to the memory control unit 43 together with the memory access signal. When an image output command is received from the memory control unit 43, the image data from the memory control unit 43 is output in synchronization with the output image synchronization signal.
[0012]
4-2 Explanation of the image memory 42
The image memory 42 is composed of a semiconductor storage element such as a DRAM and stores at least one image signal. The memory capacity is 8 MB in total, including 4 Mbytes for A3 size (as binary image data at 400 DPI) and 4 Mbytes of memory for electronic sort storage. Read control and write control are performed from the memory control unit 43.
[0013]
4-3 Description of Memory Control Unit 43
The memory control unit 43 includes a CPU and a logic LSI, and communicates with the system control unit 2. The memory control unit 43 receives a command from the system control unit 2, performs an operation setting according to the command, transmits it as status information to notify the state of the storage unit 4, and transmits a transfer rate capability ( The input / output speed capability is transmitted to the system control unit 2 as the speed capability.
The operation commands from the system control unit 2 include image input, image output, compression, decompression, and the like. Image input and image output commands are input to the image input / output DMAC 41, and compression-related commands are image transfer DMAC 44 and code transfer DMAC 45. To the compression / decompression unit 46.
In addition, an image transfer interruption / resumption command can be received from the system control unit 2, and data being executed can be interrupted to receive another operation command from the system control unit 2.
[0014]
Next, the configuration and operation of the memory control unit 43 will be described in detail.
FIG. 5 shows the configuration of the address generation unit and comparison unit of the memory control unit 43. The function will be described for each block.
5-1 Explanation of Input / Output Image Address Counter 431
The input / output image address counter 431 is an address counter that counts up in response to the input / output memory access request signal a, and outputs a 22-bit memory address indicating the storage location of the input / output image data in the image memory 42. The address is initialized once at the start of memory access.
5-2 Transfer image address counter 432
An address counter that counts up according to the transfer memory access permission signal b outputs a 22-bit memory address indicating the storage location of the transfer image data in the image memory 42. The address is initialized once at the start of memory access.
[0015]
5-3 Difference calculation unit 434
At the time of image input, the number of input / output processing lines output from the image input / output unit is subtracted from the number of transfer processing lines output from the compression / decompression unit 46, and the result is output to the difference comparison unit 440.
5-4 Line setting unit 433
The difference comparison unit 440 is notified from the system control unit 2 and sets a value to be compared with the difference between the number of input processing lines output from the difference calculation unit 434 and the number of transfer processing lines. An arbitrary value can be set.
5-5 About the difference comparison unit
At the time of image input, the number of difference lines output from the difference calculation unit 434 is compared with the set value output from the line setting unit 433, and an error signal is output when the number of difference lines = the set value. When it becomes 0, the transfer request mask signal is made active. Otherwise, active is not output in the state where the input or output image is not being processed.
5-6 Address selector 439
Either an input image or a transfer image address is selected by a signal from the arbiter 437.
[0016]
5-7 About Arbiter 437
The arbiter 437 outputs a memory access permission signal b to the compression / decompression unit 46. The memory access permission signal is output under the condition that the address comparison signal c is active and the input / output memory access request signal a is inactive.
5-8 Request mask 438
The transfer memory access request signal for accessing the compression / decompression unit 46 is masked (to be disabled) by the comparison result from the difference comparison unit 440, and the transfer process is stopped.
5-9 About the access control circuit 441
The input physical address is divided into a row address and a column address corresponding to the semiconductor memory (DRAM) by a signal from the access control circuit 441 and output to an 11-bit address bus. Also, in accordance with an access start signal from the arbiter, a DRAM control signal (RAS, CAS, WE) is output.
The memory control unit 43 includes the above elements.
[0017]
Next, the functional operation of the memory control unit 43 will be described.
The memory control unit 43 is initialized by an image input instruction from the system control unit 2 and enters a waiting state for image data. Image data is input to the storage unit 4 by operating a scanner (not shown). The input image data is once written in the semiconductor memory 42. The number of processing lines of the written image data is counted by the image input / output DMAC 41 and input to the memory control unit 43. The compression / decompression unit 46 receives an image transfer command and outputs a transfer memory access request signal. While one line is input, the request mask 438 outputs a mask signal, and the transfer memory access request signal is Masked and no actual memory access is performed. When the input data from the image input / output unit DMAC 41 has been input for one line, the mask of the transfer memory access request signal is released, the semiconductor memory 42 is read, and the transfer process of the image data to the compression / decompression unit 46 is started. Is done. Also, during processing, the difference calculation unit 434 calculates the difference between the two processing lines, and if it becomes 0, the transfer memory access request signal is masked so that the address is not overtaken.
[0018]
Returning to FIG. 4, the description of the remaining components will be continued.
About 4-4 Image Transfer DMAC44
The image transfer DMAC 44 includes a CPU and a logic LSI, and is a DMAC used when compressing uncompressed information, and communicates with the memory control unit 43. A command is received from the memory control unit 43, operation setting is performed according to the command, and status information indicating the state of the image transfer DMAC 44 is transmitted to the memory control unit 43. When a compression command is received from the system control unit 3 via the memory control unit 43, a memory access request signal is output to the memory control unit 43, and image data is received from the memory control unit 43 when the memory access permission signal is active. To the compression / decompression unit 46. Also, an address counter that counts up in response to a memory access request signal is built in, and a 22-bit memory address indicating the storage location of the image memory 42 in which image data is stored is output.
[0019]
4-5 About code transfer DMAC45
The code transfer DMAC 45 is composed of a CPU and a logic LSI, and is a DMAC used when decompressing compressed information. It communicates with the memory control unit 43, receives a command from the memory control unit 43, performs operation settings according to the command, and transmits status information indicating the state of the code transfer DMAC 45. When a decompression command is received from the system control unit via the memory control unit, a memory access request signal is output to the memory control unit 43. When the memory access permission signal is active, image data is received and sent to the compression / decompression unit 46. Forward. In addition, an address counter that counts up in response to a memory access request signal is incorporated, and a 22-bit memory address indicating the storage location of the image memory in which image data is stored is output to the memory control unit 43.
4-6 About the compressor / decompressor 46
The compression / decompression unit 46 is composed of a CPU and a logic LSI, and communicates with the memory control unit 43. A command is received from the system control unit 3 via the memory control unit 43, and an operation setting corresponding to the command is performed. Also, status information indicating the state of the compression / decompression unit 46 is transmitted to the memory control unit 43. The compression / decompression unit 46 compresses / decompresses binary image data by the MH encoding method.
4-7 About HDC Controller 47
The HDC controller 47 is composed of a CPU and a logic LSI, and communicates with the memory control unit 43 to control the hard disk 48. A command is received from the memory control unit 43, operation setting is performed according to the command, and the HDC controller 47 transmits status information indicating a state. Reads the status of the HDD 48 and transfers data.
4-8 About HDD48
The secondary storage device is composed of a hard disk.
The above is the configuration of the storage unit 4.
[0020]
Next, a general video input DMAC will be described.
FIG. 6 is for explaining the descriptor access operation and data transfer processing of the video input DMAC 6. The image data in the figure is divided into four bands, and the image data of the number of lines set in each band is transferred.
A procedure for adding the total number of transfer lines in one image will be described below.
First, when the video input DMAC 6 receives a transfer command, the DMA is started, the descriptor 1 is read-accessed to the chain destination address (a) set in advance by the CPU in the internal descriptor storage register 61, and the contents of the descriptor 1 in the memory are read. Is loaded into the descriptor storage register 61. The loaded contents are composed of 4 words.
(1) Chain destination address 611 indicating the storage address of the next descriptor,
(2) a data storage destination address 612 indicating the head address of data to be transferred;
(3) Number of data transfer lines 613 indicating the amount of data to be transferred in the number of lines. (4) Format information 614 on whether or not to generate a CPU interrupt when transfer of the set number of lines is completed.
In the least significant bit of the format information 614, a bit indicating whether or not to generate a CPU interrupt when the set line number transfer is completed is arranged. When the least significant bit is 0, a CPU interrupt is generated, and when 1, the CPU interrupt is masked.
[0021]
In the example of FIG. 6, it is assumed that the image is divided into four bands, and the least significant 1 bit of the format information of each descriptor is 0, 0, 0, 0 in order from 1 to 4. When the transfer of image data for each band is completed, a CPU interrupt is generated. The interrupt is generated, and the line number currently set is determined by adding the number of lines set in each descriptor to the number of lines so far. Transfer processing while detecting.
Similarly, when data is transferred from the image memory to the HD through the compression / decompression unit (primary storage device → secondary storage device), the image transfer DMAC transfers for each band, but sets a descriptor for each band. Therefore, the number of image lines in one band is set as the number of descriptor lines. At that time, the transfer destination of the code transfer DMAC is set in the HDD controller.
A storage address is set in the HDD controller, and image data can be transferred through a path of image memory → image transfer DMAC → compressor / decompressor → code transfer DMAC → HDD controller → HD. After data transfer is completed, the HDD controller notifies the HD of the used data amount (memory capacity actually stored in the HD), and secures the address and the used data amount stored in the HD in the primary storage device. Stored in the HDD management area. The memory control unit controls the data transfer from the image memory to the secondary storage unit so as not to overtake the data transfer from the image input device to the image memory.
[0022]
Conversely, when data is transferred from the HD to the image memory through the compression / decompression unit (secondary storage device → primary storage device), when the data is stored in the HD stored in the HDD management area secured in the primary storage device The storage address and the amount of used data are acquired, the storage address is set in the HDD controller, the amount of used data is set in the code transfer DMAC, the number of lines after decompression is set in the image transfer DMAC, and the HD → HDD controller → Image data can be transferred through a path of code transfer DMAC → compressor / decompressor → image transfer DMAC → image memory.
[0023]
Next, an embodiment of the present invention will be described.
First embodiment
First, an outline will be described taking an ADF (automatic document feeder) as an example of input processing.
Although it takes time for the document to be transported from the position of the ADF paper feed tray set to the reading start position, this time is determined by the distance from the paper feed tray to the reading start position and the ability of the paper feed motor. For example, assuming that the conveyance speed of the paper feed motor is 50 mm / sec and the distance from the paper feed tray to the reading start position is 100 mm, the time required for preparation for feeding the next original is 2 seconds. If the system control unit can complete the process currently being executed within 2 seconds, it can accept the preparation for the next reading process. When it is predicted that the process cannot be completed within 2 seconds, the input unit is notified that the reception is impossible. Then, the input means does not feed paper, waits until a signal indicating completion of input preparation is notified from the system control unit, and the ADF processing stops. In this way, preparation is required prior to the next input process. With attention to this preparation period, it is determined whether or not the process currently being executed is completed during this preparation period. When it is determined that the process is completed, the following process is performed. By providing such determination means, ADF processing can be performed smoothly.
Next, the configuration and procedure for performing this control will be described.
FIG. 7 is a block diagram for explaining the timing management / control of the flow of the image signal between the input or output device and the storage device according to the present invention.
The operator determines the control content of the image signal A using the operation unit 6 ((1)). The system control unit 3 acquires the transfer rate s set from the input or output device, and calculates the time t required to complete the currently executing process using the acquired transfer rate s. Upon receiving a request for image signal input or output processing, the system control unit 3 designates a time T required for the preparation of the processing, and the currently executed control is designated from the time t and the designated time T. It is determined whether it can be completed within the specified time T, and when it is determined that it can be completed, an execution request is issued ((2)).
When an execution request is issued, the image signal A is fetched from the input device 1 such as a scanner, a fax machine, a copying machine or the like in accordance with the execution request (4), and is controlled by the memory control unit 43 (3). Accumulated in the primary storage unit 42 (5). Next, the image signal A is compressed from the primary storage unit 42 and stored in the secondary storage unit 48 (7) under the control of the memory control unit 43 (6). On the other hand, the image signal A stored in the secondary storage unit 48 is expanded and sent to the primary storage unit 42 (under control of the memory control unit 43) ((8)), and the writing unit and the like. Is output to the output device 2 (9).
[0024]
FIG. 8 is a processing flow of the system control 3 when the image signal A in FIG. 7 is input or output. For example, the case of reading processing will be described as an example.
First, the system control unit 3 acquires the transfer speed s set from the input or output device [S81], and when there is an input or output request for the image signal A, the distance from the document tray to the reading position, the paper feed motor The parameters such as the ability are set [S82]. When the control unit 3 designates the time T required for preparation for document reading based on the parameters [S83], the control unit 3 calculates the time t required to complete the currently executed process using the acquired transfer speed s [ S84]. From this time t and the specified time T, it is determined whether the currently executed process can be completed within the specified time [S85]. The determination result is notified to the input or output device [S86], and it is determined whether to execute the determination [S87]. If it is completed within the specified time T, a command for processing is issued [S88]. If it is not completed within the specified time T, no processing is performed [S89].
Note that the time required to complete the read processing preparation of the writing unit is the time required for transfer from the paper feed tray to the print position. In this way, the time required for preparation of input or output processing refers to the time required for processing that must be prepared prior to the input or output processing.
The determination as to whether the control requested in [S85] can be completed within the designated time will be described by taking, for example, the case where an image is read from the image reading unit 1 (when an image signal is sent to the memory 42) as an example. To do.
FIG. 9 shows a configuration in which the image data read by the image reading unit 1 is transferred to the image memory 42 under the control of the system control unit 3. The transfer speed s from the image reading unit 1 to the image memory 42 is determined by the reading speed of the reading unit 1, and the speed depends on the hardware of the reading unit 1. The system control unit 3 communicates with the reading unit 1 to acquire the image signal transfer speed s from the reading unit 1 and stores the data. At this time, not only the image signal transfer speed s but also unique information such as the device ID, software version, and hardware version of the image input or output means is acquired and stored as a data table. Hereinafter, the term image signal transfer time is used, and the image signal transfer time t means the time from the current time point of one image signal device (for example, a reading unit) to another device (image memory) until the transfer is completed. To do.
(1) Case where image information is sent from the image reading unit 1 to the image memory 42 (2) Case where image information is transferred from the image memory 42 to the secondary storage device 48 (3) Transfer from the secondary storage device 48 to the image memory 42 Case of transfer (4) There are four cases of transfer from the image memory to the output means. As a representative example, a method for calculating the image signal transfer time t for case 1 will be described.
[Case where image information is sent from image reading unit 1 to image memory 42]
The image reading unit 1 stores the read image information in the buffer memory of the reading unit, and transfers it to the image memory 42. The image signal transfer time t is calculated from the image signal transfer speed s acquired from the reading unit 1 and the image signal data amount d transferred from the image signal transfer speed s, and the calculation formula is as follows.
d ÷ s = t
For example, when the image signal transfer speed is 10 MB / second and the amount of image signal data to be transferred is 5 MB, the image signal transfer time is
5MB ÷ 10MB / sec = 0.5 sec
It becomes.
Since the calculated transfer processing time is the time required for image signal input or output processing,
Next, the calculated transfer processing time t and the specified designated time T are compared to determine whether input or output processing is possible within the designated processing time. Thereafter, the determination result is notified to the input or output unit. Then, for example, the reading unit 1 performs control to maximize productivity if the image signal transfer time t is within the specified time T based on the determination notification. When the image signal transfer time t is greater than the specified time T, The control is switched to the control that does not jam the original without performing the control for maximizing the performance.
[0025]
Second embodiment
FIG. 9 shows a configuration in which two image input devices x and y transmit image signals to the image forming device 2 under the control of the system control unit 3. Image input or output means at power-on using means for transmitting and receiving commands and responses between the image input or output devices x and y and the system control unit 3 and between the image forming device 2 and the system control unit 3 Specific device information (device ID, software version, hardware version, etc.) X, Y is sent to the system control unit 3 from the image input or output devices x, y. The system control unit 3 stores these unique device information X and Y.
On the other hand, the image forming apparatus 2 registers the unique device information A, B, and C of the image input or output devices a, b, and c for which connection is set in advance as a data table. Furthermore, the image forming unit 2 compares the unique information X, Y acquired from the image input or output device x, y at the time of power-on with the unique information A, B, C of the data table, and if there is a mismatch, It is determined that this is not a control target, and it is not determined whether the input or output processing of the image signal is possible within the time designated by the means for designating the time during which the input or output processing of the image signal is allowed.
By doing so, the image forming apparatus can automatically determine the consistency with the input or output device even if a large number of various types of devices are connected, and can prevent malfunctions and abnormal operations.
[0026]
Third embodiment
In the third embodiment, in FIG. 7, when data is transferred from the image reading unit 1 to the image forming apparatus 2, it is determined whether or not data input or output processing can be performed within the specified time T. Selection means for selecting whether or not to select a function is provided.
Next, the reason for providing this selection means will be described.
The processing performance of the image signal input or output means connected to the image forming apparatus and the storage device is improved, and there is a case where it is not necessary to determine the processing time or the processing time cannot be determined. In this case, the processing request for specifying the processing time, the setting of the image signal transfer time, and the information acquisition processing are not required. In this way, the determination function may be selected so as to deal with cases where the above processing is necessary and unnecessary cases.
It is possible to store in the NVRAM (Non-volatileRAM) of the memory control unit 43 as an initial setting condition whether or not to select the setting of the specified time, the calculation of the image signal transfer time, and the determination of whether or not processing is possible. It is also possible to instruct as a parameter from the system control unit 3 to the memory control unit 4 without being stored in the NVRAM as setting conditions.
Fourth embodiment
FIG. 11 is a time chart for explaining image input or output processing when interrupt processing B occurs during execution of ADF processing. Assume that the current processing of the ADF is A, the next processing of the ADF is C, and the time required for document feeding preparation related to the processing C is T.
The time t1 required for the process A to be completed from the present time and the time t2 required for the process B (the time required for the entire process including the preparation period for the process B and the process time for the process B) are calculated. . Next, it is determined whether the process A is completed within the preparation time T and the interrupt process B can be performed. If it is determined that the process A and the interrupt process B can be completed within the time T, the ADF process can be continued, the interrupt process B can be performed, and a more efficient process can be performed.
[0027]
【The invention's effect】
  According to the present invention, the document is transported from the set position to the reading position, and the image input unit that reads the document being transported to generate the image signal and the image signal transferred from the image input unit are stored. In an image forming apparatus having a storage means and an image output means for writing an image on a sheet based on an image signal, when an image input request is made during transfer of the image signal from the image input means to the image storage means, Only when the transfer of the image signal currently being executed is completed within the time from the set position to the reading position, the document for the requested image input is transferred during the transfer of the image signal. , Efficient use of the device, and prevention of malfunction of the device can be realizedThe
  Also,According to the present invention, an image input unit that reads a document and generates an image signal, an image output unit that conveys a sheet from a setting position to a writing position, and writes an image on the sheet based on the image signal, and the image In an image forming apparatus having an image storage means for storing an image signal transferred to the output means, when an image output request is made during the transfer of the image signal from the image storage means to the image output means, the paper is set to the set position. By transferring the paper for the requested image output during the transfer of the image signal only when the transfer of the image signal currently being executed is completed within the time from the transfer to the writing position. Efficient use and prevention of malfunction of equipmentThe
[Brief description of the drawings]
FIG. 1 is a diagram showing an outline of a digital copying machine.
FIG. 2 is a view of a document table viewed from above.
FIG. 3 is a diagram illustrating an image synchronization signal output from an IPU of a reading unit.
FIG. 4 is a diagram illustrating a configuration of a storage unit.
FIG. 5 shows a block diagram of a memory control unit.
FIG. 6 is a diagram for explaining a descriptor access operation and a data transfer operation of a video DMAC.
FIG. 7 shows a schematic diagram of a first embodiment of the invention.
FIG. 8 shows a flow of the first embodiment of the present invention.
FIG. 9 is a block configuration diagram of the first embodiment of the present invention.
FIG. 10 is a block configuration diagram of a second embodiment of the present invention.
FIG. 11 shows a time chart according to a fourth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Reading part of a digital copying machine, 2 ... Image formation part of a digital copying machine, 3 ... System control part, 4 ... Memory | storage part, 41 ... Image input / output DMAC, 42 ... Image memory, 43... Memory control unit, 48.

Claims (7)

An image input unit that transports the document from the set position to the reading position, reads the document being transported and generates an image signal, an image storage unit that stores the image signal transferred from the image input unit, and an image signal In an image forming apparatus having image output means for writing an image on a sheet based on
Means for setting the transfer speed of the image signal from the image input unit to the image storage means, transmission capacity and before Kiten feed rate Toka Latin of the image signal to be transferred to the image storage means from said image input means A transfer time calculating means for calculating a time required for completion; a document transport time calculating means for calculating a time until the document is transported from a set position to a reading position; and an image input request during transfer of the image signal. A determination is made as to whether or not the transfer of the image signal currently being executed is completed within the time calculated by the document conveyance time calculation unit, based on the calculation results of the transfer time calculation unit and the document conveyance time calculation unit. a judging means for performing said only when it is determined to be completed by the determining means, system to execute the conveyance of the document for the requested image input during the transfer of the image signal to said image input means An image forming apparatus, comprising a means. An image input unit that reads an original and generates an image signal, an image output unit that conveys a sheet from a setting position to a writing position, and writes an image on the sheet based on the image signal, and is transferred to the image output unit In an image forming apparatus having image storage means for storing an image signal ,
The transfer is completed from the means for setting the transfer speed of the image signal from the image storage means to the image output means, the capacity of the image signal transferred from the image storage means to the image output means, and the transfer speed. There is a transfer time calculation means for calculating the time required for the paper, a paper transport time calculation means for calculating the time until the paper is transported from the set position to the writing position, and an image output request is made during the transfer of the image signal. Then, based on the calculation results of the transfer time calculation means and the paper transfer time calculation means, it is determined whether or not the transfer of the currently executed image signal is completed within the time calculated by the paper transfer time calculation means. Only when it is determined to be completed by the determination means and the determination means, the image output means causes the image output means to carry the paper for the requested image output during the transfer of the image signal. An image forming apparatus; and a control means. The image forming apparatus according to claim 1 Symbol placement,
The image forming apparatus stores unique device information of at least one or more image input units, and at least one or more image input units are connected to the image forming device, and the unique device information of the connected image input unit is stored. And a means for comparing the acquired and stored unique device information of the image input means with the unique device information stored in the image forming apparatus, and the determination means includes: The image forming apparatus , wherein the determination is performed only when the comparison results of the unique device information match . The image forming apparatus according to claim 2 .
The image forming apparatus stores unique device information of at least one or more image output means, and at least one or more image output means is connected to the image forming apparatus, and the unique device information of the connected image output means. And a means for comparing the acquired and stored unique device information of the image output means with the unique device information stored in the image forming apparatus, and the determination means includes: The image forming apparatus , wherein the determination is performed only when the comparison results of the unique device information match . The image forming apparatus according to claim 1 or 2,
An image forming apparatus comprising: a selection unit for selecting whether to execute the determination function of the determination unit . An image input unit that transports the document from the set position to the reading position, reads the document being transported and generates an image signal, an image storage unit that stores the image signal transferred from the image input unit, and an image signal An image signal input processing method in an image forming apparatus having image output means for writing an image on a sheet based on
The transfer is completed from the step of setting the transfer speed of the image signal from the image input means to the image storage means, the capacity of the image signal transferred from the image input means to the image storage means, and the transfer speed. A transfer time calculating step for calculating a time required for the document, a document transport time calculating step for calculating a time until the document is transported from the set position to the reading position, and an image input request during the transfer of the image signal. At this time, based on the calculation results of the transfer time calculation step and the document transfer time calculation step, it is determined whether or not the transfer of the currently executed image signal is completed within the time calculated in the document transfer time calculation step. A determination step; and a step of conveying the document for the requested image input during the transfer of the image signal only when it is determined to be completed by the determination step. Input processing method for an image signal to be. An image input unit that reads an original and generates an image signal, an image output unit that conveys a sheet from a setting position to a writing position, and writes an image on the sheet based on the image signal, and is transferred to the image output unit An image signal output processing method in an image forming apparatus having an image storage means for storing an image signal,
The transfer is completed from the step of setting the transfer speed of the image signal from the image storage means to the image output means, the capacity of the image signal transferred from the image storage means to the image output means, and the transfer speed. There is a transfer time calculation step for calculating the time required for the transfer, a paper transfer time calculation step for calculating the time until the paper is transported from the set position to the writing position, and an image output request during the transfer of the image signal. A determination is made as to whether or not the transfer of the currently executed image signal is completed within the time calculated in the paper transport time calculation step based on the calculation results of the transfer time calculation step and the paper transport time calculation step. And a step of conveying the paper for the requested image output during the transfer of the image signal only when it is determined to be completed by the determination step. Output processing method for an image signal to be.

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