JP2005236578A5 - - Google Patents

Description

Image forming apparatus

  The present invention relates to an image forming apparatus such as a digital copying machine, a facsimile machine, a scanner, and a digital multi-function peripheral having a plurality of functions including an image input / output function, and particularly stores image data read by an image reading unit. The present invention relates to an image forming apparatus having a large-capacity image storage means such as a hard disk storage device.

JP 2002-278742 A.

  Used in image forming apparatuses such as digital multifunction peripherals, facsimile machines, and digital copiers configured by combining image reading apparatuses such as scanners, image forming apparatuses such as printers, and image storage apparatuses that store (store) image data The image data is converted and processed according to the user's request. There are various image data conversion methods depending on the output form of the image data. For example, the facsimile apparatus uses the MR encoding method, and the color still image output to the recording paper or the display device uses the JPEG encoding method. Furthermore, high-speed processing of image input / output including conversion of image data is also required.

  Therefore, in the prior art, in order to execute image data conversion at high speed, a buffer memory for performing image data conversion for each image input / output unit is mounted in addition to an image storage device for storing image data. There are many. Data conversion is performed by temporarily storing image data in the buffer memory.

  On the other hand, in recent years, standards related to information security have been established, and when image data is held and managed in the image storage device, means for preventing leakage of the held image data are also considered. ing. For example, when a hard disk storage device is used as an image storage device, functions such as data encryption and file access restriction (password setting function) are implemented in order to prevent leakage of stored image data. A product that has a function to completely erase not only the file allocation data but also the image data area itself at the time of erasing, and a mechanism that allows users to easily attach and detach the storage medium to prevent their own data leakage There is also.

  Regarding the confidentiality of the image data in the image storage device, it is also a problem that the image data is left in the image storage device for a long time. In the prior art disclosed in Patent Document 1, a third party sees it. Therefore, inconvenient image data is stored in a storage device in the image output apparatus (image forming apparatus) so as not to be left unattended. In this prior art, the information processing device (host device) first sends only an image formation instruction to the image output device, and sends image data later.

  As described above, the image forming apparatus is equipped with a buffer memory for performing image data conversion for each image input / output unit such as an image reading (image input) apparatus or an image output apparatus in addition to an image storage apparatus for storing image data. There are many. When the capacity of the buffer memory is small, it is almost impossible to identify the contents of the image data from the contents of the stored data, but depending on the data conversion method, data close to one page is stored. Therefore, there is a possibility that the image data leaks if the contents of the image data are stored even if it is temporarily stored. Even if the image forming apparatus does not have a function of reading the image data stored in the buffer memory, the image data can be read intentionally. However, in the above-described conventional technology, it is difficult to employ a buffer memory at this time because it is feared that it takes a long processing time to employ a means for encrypting data.

  The present invention has been made in consideration of such circumstances, and provides an image forming apparatus capable of preventing leakage of confidentiality of image data temporarily stored in a document image reading unit of the image forming apparatus. With the goal.

To solve the problems described above, the inventions according to claim 1, stores an image reading means for reading an image on an original, one or more image data read by the image reading unit the image e Bei and storage means, before Symbol image reading means, or between said image reading means and the image storage means, the read one image temporary storage means for storing all or part of the image data, An image forming apparatus comprising: an image transfer unit that transfers image data stored in the image temporary storage unit to the image storage unit; and a data deletion unit that deletes the image data stored in the image temporary storage unit.
The data erasing unit is configured to end the erasing of the image data almost coincident with the completion of the image data transfer to the image storage unit .

The invention according to claim 2, the pre-Symbol data erasing means, characterized in that is configured to delete the image data immediately after the image data transfer to the image storage means.

Further, characterized in that the inventions of claim 3, claim 1 or in the second aspect of the present invention, which was a selection whether to erase the image data can be configured by the data erasing means And

Further, it is inventions of claim 4, wherein, in the invention of claims 1 to 3 noise crab, wherein the data erasing means is a selection is configurable erase unit when erasing image data Features .

Further, the inventions of claim 5, wherein, in the invention of claim 3 or claim 4, wherein, characterized by comprising operating means for specifying the selection to the user.

In the invention of claim 1 Symbol placement, when transferring store all or part of the images data read from the original to the image reading portion, stored the image data to the image storage means, the image reading unit erasure of the image data are finished transferring stored on the side is, since substantially coincides with final Ryosuru the completion of image data transfer to the images storage means, more effective and security breaches of the image data from the image reading portion Can be prevented.

Further, in the invention of claim 2, since the erased image data immediately after the image data transfer to the images storage means, like the invention described in claim 1, the image data from the image reading portion Confidential leakage can be prevented more effectively.

Further, in the invention described in claim 3, in the invention described in claim 1 or 2, it is possible to select whether or not to delete the image data. Save time.

In the invention according to claim 4, in the invention according to any one of claims 1 to 3, the erasing unit for erasing the image data can be selected, so that the image data erasing is performed in parallel with the image data compression. When performing, it is possible to select a more appropriate erasing unit so that the image data erasing time is within the compression time.

Further, in the invention according to claim 5, in the invention according to claim 3 or 4 , since the above-mentioned selection can be specified by the user, the user easily makes a desired selection according to the situation. be able to.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the components, types, combinations, shapes, relative arrangements, and the like described in this embodiment are merely illustrative examples and not intended to limit the scope of the present invention only unless otherwise specified. .

  FIG. 1 is a block diagram of a digital copying machine showing a first embodiment of an image forming apparatus of the present invention. With such a configuration, the reading unit 1 first exposes a document surface while scanning it with an exposure lamp 12 movable along the document table 11, and photoelectrically converts the reflected light by a CCD (image sensor) 13. An electric signal corresponding to the intensity of light is obtained. Then, an IPU (image processing unit) 14 performs processing such as shading correction on the electrical signal, A / D conversion to 8-bit digital data, and further performs image processing such as scaling processing and dither processing. The image data is sent to the image forming unit 2 together with the image synchronization signal. FIG. 2 shows the document table viewed from above.

  The scanner control unit 15 performs detection of various sensors and control of a drive motor and the like to execute the above process, and sets various parameters in the IPU 14. Further, in the image forming unit 2, the rotating photosensitive member 22 uniformly charged by the charging charger 21 is exposed with laser light modulated by image data from the writing unit 23. As a result, an electrostatic latent image is formed on the photosensitive member 22, and the developing device 24 develops the toner with toner so that the toner image is generated. On the other hand, the transfer paper previously fed from the paper feed tray 26 by the paper feed roller 25 and waiting by the registration roller 27 is transported in accordance with the rotation and timing of the photoconductor 22 and is transferred onto the photoconductor by the transfer charger 28. The toner is transferred onto the transfer paper, and the transfer paper is separated from the photoreceptor 22 by the separation charger 29. Further, the toner image on the transfer paper is heated and fixed by the fixing device 30, and discharged to the discharge tray 32 by the discharge roller 31. On the other hand, the toner image remaining on the photoconductor 22 after the transfer is removed by a cleaning device 33 that is in pressure contact with the photoconductor 22, and the photoconductor 22 is neutralized by a static elimination charger 34. The plotter control unit 35 performs detection of various sensors and control of the drive motor and the like in order to execute the above process.

  Next, the state of the image synchronization signal output from the IPU 14 in the reading unit 1 will be described with reference to the timing chart shown in FIG. In FIG. 3, a frame gate signal (/ FGATE) is a signal representing an image effective range for an image region in the sub-scanning direction, and image data during which this signal is low is valid. As shown in FIG. 3, this / FGATE is asserted (to make a signal present state) or negated (to make a no signal state) at the falling edge of the line synchronization signal (/ LSYNC).

  Also, / 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 sent image data is one for one cycle of PCLK and is divided into 400 DPI equivalents starting from the position where the range of the arrow in FIG. 3 ends, and is sent as raster format data. . The effective sub-scanning range of image data is usually determined by the transfer paper size.

  In FIG. 1, the system control unit 3 detects an input state of the operation unit 4 by a user, and reads a reading unit 1, an image forming unit 2, a storage unit 5, a facsimile (FAX) unit 6, and an interface (I / I). F) Various parameters are set in the unit 7 and a process execution instruction is performed. The state of the entire system is displayed on the operation unit 4. The instruction to the system control unit 3 is made by key input to the operation unit 4 by the user.

  The FAX unit 6 encodes the image data delivered from the system control unit 3 based on the data transfer rule of G3 or G4 facsimile communication, and sends it to the telephone line. Further, the data transferred from the telephone line to the FAX unit 6 is restored and converted into binary image data, which is sent to the writing unit 23 of the image forming unit 2.

  The I / F unit 7 transmits data in the storage unit 5 to the outside according to an instruction from the system control unit 3, and stores data received from the outside in the storage unit 5.

  The selector unit 8 changes the state of the selector according to an instruction from the system control unit 3, and the source of image data at the time of image formation is any of the reading unit 1, the storage unit 5, the FAX unit 6, and the I / F unit 7. Choose from.

  In addition, the storage unit 5 normally stores image data of a document input from the IPU 14 and is used for a copy application such as repeat copy or rotated copy. Further, it is also used as a buffer memory for temporarily storing binary image data from the FAX unit 6, and further used as a means for storing unique information input from the input / output device via the I / F unit 7. . The system control unit 3 gives these data storage instructions.

  FIG. 4 shows the configuration of the storage unit 5. Hereinafter, the function of the storage unit 5 will be described for each block with reference to FIG. First, an image input / output DMA controller (DMAC) 51, which is composed of a CPU and a logic circuit, communicates with the memory control unit 52 to receive a command, sets an operation according to the command, It is transmitted as status information to notify the state of the input / output DMAC 51. When an image input command is received, 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 52 together with the memory access signal as needed. When an image output command is received, the image data from the memory control unit 52 is output in synchronization with the output image synchronization signal.

  Next, the image memory 53 is a memory for storing image data, and is composed of a semiconductor storage element such as a DRAM. The storage capacity is 4 Mbytes for the A3 size of 400 DPI / binary image data, 4 Mbytes for electronic sort storage, 6 Mbytes for the data transfer work area, and 2 Mbytes for the image data management area, for a total of 16 Mbytes. The memory control unit 52 controls reading and writing.

  The memory control unit 52 is composed of a CPU and a logic circuit, communicates with the system control unit 3 to receive a command, performs operation settings in accordance with the command, and provides status information for notifying the state of the storage unit 5 Send as. The operation commands received from the system control unit 3 include image input, image output, compression, decompression, etc. In the case of image input and image output commands, data is transmitted to the image input / output DMAC 51, and compression related commands In this case, the data is transmitted to the compression / decompression unit 56 via the image transfer DMAC 54 or the code transfer DMAC 55.

  FIG. 5 shows the configuration of the address generation unit and the comparison unit of the memory control unit 52. Hereinafter, the function will be described for each block. First, the input / output image address counter 61 is an address counter that counts up in response to an input / output memory access request signal, and outputs a 22-bit memory address indicating a storage location where the input / output image data is stored. Note that the address is initialized once at the start of memory access.

  Next, the transfer image address counter 62 is an address counter that counts up in response to a transfer memory access permission signal, and outputs a 22-bit memory address indicating a storage location where the transfer image data is stored. The address is initialized once when the memory access is started.

  Further, the line setting unit 63 has a value for comparing the difference between the input processing line and the transfer line output from the difference calculation unit 65 in the difference comparison unit 64 when the semiconductor memory is used as a buffer at the time of image input. Set by the control unit 3. The difference calculation unit 65 subtracts the number of input / output processing lines output from the image input / output DMAC 51 from the number of transfer processing lines output from the compression / decompression unit 56 when inputting an image, and outputs the result to the difference comparison unit 64.

  Also, the difference comparison unit 64 compares the number of difference lines output from the difference calculation unit 65 during image input with the set value output from the line setting unit 63. If the number of difference lines = the set value, an error signal is output. When the difference line number becomes 0, the transfer request mask signal of the comparison result output to the arbiter 66 is made active. Otherwise, active is not output in the state where the input / output image is not in operation. The arbiter 66 outputs a memory access permission signal for accessing the compression / decompression unit 56. The memory access permission signal is output under the condition that the address comparison signal is active and the input / output memory access signal is inactive.

  The address selector 67 is a selector selected by the arbiter, and selects either the input image or the transfer image address. The request mask 68 masks the transfer memory access request signal for accessing the compression / decompression unit 56 in accordance with the comparison result from the difference comparison unit 64 (stops the transfer process), and stops the transfer process.

  Further, the access control circuit 69 divides the input physical address into a row address and a column address corresponding to the image memory (for example, DRAM) 53, and outputs it to the 11-bit address bus. Further, in accordance with an access start signal from the arbiter 66, a DRAM control signal (RAS, CAS, WE, etc.) is output.

  With such a configuration, the storage unit 5 is initialized by an image input instruction from the system control unit 3 and enters a standby state for image data. When image data is input to the storage unit 5 when the reading unit 1 operates, The memory control unit 52 once writes the image data into the image memory 53. At this time, the number of processing lines of the written image data is counted by the image input / output DMAC 51. At this time, the compression / decompression unit 56 receives the image transfer command and outputs a transfer memory access request signal. However, the request mask is masked by the request mask unit 68 in the memory control unit 52, and the actual memory access is performed. Is not done. Thereafter, when the data input from the image input / output DMAC 51 is completed for one line, the masking of the transfer memory access request signal is released, the reading from the image memory 53 is performed, and the transfer operation of the image data to the compression / decompression unit 56 is performed. Be started. Further, during this operation, the difference calculating unit 65 calculates the difference between the two processing lines, and when it becomes 0, the request masking unit 68 masks the transfer memory access request signal so that the address is not overtaken.

  Next, the image transfer DMAC 54 will be described. The image transfer DMAC 54 is composed of a CPU and a logic circuit, communicates with the memory control unit 52, receives a command, performs operation settings in accordance with the command, and transmits status information for informing the state. When a compression command is received, a memory access request signal is output to the memory control unit 52. When the memory access permission signal is active, image data is received and transferred to the compression / decompression unit 56. In addition, an address counter that counts up in response to a memory access request signal is built in, and a 22-bit memory address indicating a storage location where image data is stored is output.

  The code transfer DMAC 55 is composed of a CPU and a logic circuit, communicates with the memory control unit 52, receives a command, sets an operation according to the command, and transmits status information for informing the state. . When an expansion command is received, a memory access request signal is output to the memory control unit 52. When the memory access permission signal is active, image data is received and transferred to the compression / decompression unit 56. In addition, an address counter that counts up in response to a memory access request signal is built in, and a 22-bit memory address indicating a storage location where image data is stored is output.

  The compression / decompression unit 56 is composed of a CPU and a logic circuit, communicates with the memory control unit 52, receives a command, performs operation setting according to the command, and transmits status information for informing the state. To do. Binary data is processed by the MH encoding method.

  The HDD controller 57 includes a CPU and a logic circuit, communicates with the memory control unit 52, receives a command, and sets an operation according to the command. Also, status information for notifying the state of the hard disk storage device (HDD) 58 as a secondary storage device is transmitted, the status is acquired from the HDD 58, and data transfer with the HDD 58 is performed.

  The operation of the entire storage unit 5 is as follows. When inputting an image and accumulating data, the image input / output DMAC 51 writes the image data in a predetermined image area of the image memory 53 in accordance with an instruction from the system control unit 3. Read from 53. At this time, the image transfer DMAC 54 counts the number of image lines.

  In this embodiment, the image reading unit described in the claims is realized by the image reading unit 1, the image storage unit is realized by the HDD 58, the image temporary storage unit is realized by the image memory 53, and the image transfer unit is controlled by the memory. The data erasing unit is realized by the system control unit 3, the memory control unit 52, and the like.

  With this configuration, in this embodiment, when reading an image, all or part of the read image data is stored in the image memory 53 provided between the reading unit 1 and the HDD 58, and the image data is stored. The image data is transferred to the compression / decompression unit 56 by the image transfer DMAC 54, where data compression is performed by MH encoding, and the encoded image data is transferred to the HDD 58 by the code transfer DMAC 55. At that time, the system control unit 3 erases the transferred image data in the image memory 53 via the memory control unit 52.

  FIG. 6 is a software configuration diagram of a digital multi-function peripheral, showing a second embodiment of the present invention. Here, an image forming apparatus in which the functions of each apparatus such as a printer, a copier, a facsimile machine, and a scanner are housed in one housing is called a digital multifunction machine (hereinafter abbreviated as a multifunction machine). As shown in the figure, this multifunction device includes a program (software) group 71 including an application program group 74 and a platform program group 75, an activation unit 72, and hardware resources 73. When the multifunction device is powered on, the activation unit 72 operates first, and starts the application program group 74 and the platform program group 75. For example, the activation unit 72 reads the application program group 74 and the platform program 75 from an HDD (Hard Disk Storage Device) or the like that is an external storage unit, and transfers each read program to a memory area for activation. The hardware resource 73 includes a black and white laser printer (B & W / LP) 76, a color laser printer (Color / LP) 77, other hardware resources 78 such as a scanner and a facsimile machine, and is not shown. A hardware resource as an operating environment of the program group 71, which will be described later, includes a CPU, a semiconductor memory, and various logic circuits.

  The application program 74 and the platform program 75 operate on an operating system (hereinafter referred to as OS) such as UNIX (registered trademark). The application program 74 includes a printer application 81, a copy (copying) application 82, a fax. Programs such as an application 83 and a scanner application 84 that perform processing unique to user services related to image reading and image formation are provided.

  Further, the platform program 75 interprets the processing request from the application program 74 and issues a request for acquiring the hardware resource 73, manages the one or more hardware resources 73, and manages the one or more hardware resources 73 from the control service program 79. A system resource manager (hereinafter referred to as SRM) 86 that arbitrates acquisition requests, and a handler 80 that manages hardware resources 73 in response to acquisition requests from the SRM 86 are provided.

  The control service program 79 includes a network control service program (hereinafter referred to as NCS) 91, a delivery control service program (hereinafter referred to as DCS) 92, an operation panel control service program (hereinafter referred to as OCS) 93, a fax machine. Control service program (hereinafter referred to as FCS) 94, engine control service program (hereinafter referred to as ECS) 95, memory control service program (hereinafter referred to as MCS) 96, user information control service program (hereinafter referred to as UCS) 97, a system control service program (hereinafter referred to as SCS) 98, and the like. The platform program 75 includes an API (application interface) 90 that receives a processing request from the application program 74 using a predefined function. Further, the OS causes the application program 74 and the platform program 75 to be executed in parallel as processes.

  In the above, the NCS 91 provides a service that can be commonly used for application programs that require input / output to / from the network, and distributes data received from the network side according to each protocol to each application program, Mediates when sending data from the program to the network side. For example, the NCS 91 controls data communication with a network device connected via a network by HTTP (HyperText Transfer Protocol) using httpd (HyperText Transfer Protocol Daemon).

  The DCS 92 controls distribution of stored documents and the like, and the OCS 93 controls an operation panel serving as information transmission means between the user and the multifunction peripheral. The FCS 94 sends and receives faxes using the PSTN (public telephone network) or ISDN (one of digital networks) from the application program 74, registration / quotation of various fax data managed in the backup memory, fax reading, faxing Provides an interface for receiving and printing.

  The ECS 95 controls engine units such as the black and white laser printer 76, the color laser printer 77, and other hardware resources 78. The MCS 96 performs memory control such as acquisition and release of memory and use of the HDD, and the UCS 97 manages user information. The SCS 98 performs management of the application program 74, operation unit control, system screen display, LED display, management of hardware resources 73, interrupt application control, and the like.

  The SRM 86 controls the system and manages the hardware resources 73 together with the SCS 98. For example, the SRM 86 performs arbitration and execution control in accordance with an acquisition request from an upper layer that uses the hardware resource 73 such as the monochrome laser printer 76 or the color laser printer 77. Specifically, the SRM 86 determines whether or not the hardware resource 73 for which the acquisition request has been made is available (whether it is not used by another acquisition request). The upper layer is notified that the performed hardware resource 73 is available. Further, the SRM 86 performs scheduling for using the hardware resource 73 in response to an acquisition request from an upper layer, and directly transmits the request contents (for example, paper conveyance and image forming operation by the printer engine, memory allocation, file generation, etc.). carry out.

  A handler 80 is a fax control unit handler (hereinafter referred to as FCUH) 99 that manages a fax control unit (hereinafter referred to as FCU), which will be described later, memory allocation for each program (process) described above, and management of the allocated memory. An image memory handler (hereinafter referred to as IMH) 100 for performing the above. The SRM 86 and the FCUH 99 make a processing request for the hardware resource 73 via the engine I / F 101 that mediates the processing request for the hardware resource 73 using a predefined function.

  With this configuration, in this multi-function peripheral, processing commonly required by each application program can be centrally processed by the platform program 75.

  FIG. 7 is a hardware configuration diagram of the multifunction machine. Hereinafter, this hardware configuration will be described. As shown in the figure, this multifunction device includes a controller 110, an operation panel 120, an FCU 121, a USB device 122, an IEEE 1394 device 123, an engine unit 124, and the like. The controller 110 includes a CPU 111, a system memory (MEM-P) 112, a north bridge (hereinafter referred to as NB) 113, a south bridge (hereinafter referred to as SB) 114, an ASIC (dedicated integrated circuit) 115, a local memory ( MEM-C) 116, HDD 117, and the like. The operation panel 120 is connected to the ASIC 115 in the controller 110, and the FCU 121, the USB device 122, the IEEE 1394 device 123, the engine unit 124, and the like are connected to the ASIC 115 via a PCI bus.

  In the controller 110, the local memory 116 and the HDD 117 are connected to the ASIC 115, and the CPU 111 and the ASIC 115 are connected via the NB 113. By connecting the CPU 111 and the ASIC 115 via the NB 113 as described above, it is possible to cope with a case where the interface of the CPU 111 is not disclosed. Note that the ASIC 115 and the NB 113 are not connected via a PCI bus, but are connected via an AGP (Accelerated Graphics Port) 118. By connecting via the AGP 118 instead of the low-speed PCI bus in this way, performance degradation when controlling execution of one or more processes (programs) constituting the application program 74 and the platform program 75 shown in FIG. prevent.

  The CPU 111 controls the entire multifunction machine. The CPU 111 starts and executes the SRM 86, NCS 91, DCS 92, OCS 93, FCS 94, ECS 95, MCS 96, UCS 97, SCS 98, FCUH 99, and IMH 100 shown in FIG. 6 as processes on the OS, and configures an application program 74. A printer application 81, a copy application 82, a fax application 83, a scanner application 84, and the like are activated and executed.

  The NB 113 is a bridge for connecting the CPU 111, the system memory 112, the SB 114, and the ASIC 115, and the system memory 112 is a memory that is used as a drawing memory of the multifunction peripheral. The SB 114 is a bridge for connecting the NB 113 to a ROM (not shown), a PCI bus, and peripheral devices. The local memory 116 is a memory used as a copy image buffer and a code buffer.

  The ASIC 115 is a dedicated integrated circuit for image processing having hardware elements for image processing. The HDD 117 is a storage device for storing image data, document data, programs, font data, forms, and the like. The operation panel 120 accepts input operations from the user and is directed to the user. It is an operation unit that performs display. The ASIC 115 has a DMA transfer function for transferring image data, and performs DMA transfer with the engine unit 124 via the PCI bus.

  Specifically, as shown in FIG. 8, the ASIC 115 is provided with two video input DMA controllers and a video output DMA controller, and different PCI bus addresses are allocated to the scanner input 1 and the scanner input 2. The video data transfer of the plotter output can be performed in parallel. For example, when the image data read by the scanner is transferred to the local memory 116 simultaneously on both sides, the IMH 100 secures memory for the transfer image size in the local memory 116 in response to the request from the SRM 86 and secures the transfer image sizes Xw and Yw. The memory address is set in the video input DMA controller in the ASIC 115 to enable transfer.

  FIG. 9 shows a block diagram of the configuration of the engine unit 124 when realizing simultaneous reading of both sides of a double-sided document. In FIG. 9, an image data control IF controller (hereinafter abbreviated as controller) 131 is directly controlled by the CPU 132. Also provided are image input devices 133 and 134 such as a CCD, a frame memory 135 such as a DRAM for temporarily storing input signals, and an output device 136 such as a GAVD. The controller 131 is connected to a data bus such as a PCI, and can output input data to the external storage device (HDD 117) and input data from the external storage device. The image input devices 133 and 134 are image reading elements such as a CCD, and simultaneously read from both sides of a document.

  The frame memory 135 temporarily stores image data from such image input devices 133 and 134. The frame memory 135 is used to adjust the input timing of the front and back surfaces and the data transfer rate to the PCI bus when reading both sides simultaneously.

  In this embodiment, the image reading means described in the claims is realized by the engine unit 124, the image storage means is realized by the HDD 117, the image temporary storage means is realized by the frame memory 135, and the image transfer means is PCI transfer. It is realized by the controller 152, the data erasing means is realized by the CPU 132, and the operation means is realized by the operation panel 120. Hereinafter, examples of the present invention will be described in the case of the second embodiment.

  In the MFP of the second embodiment, writing of input image data to the frame memory 135 and reading of input image data from the frame memory 135 can be executed in parallel. It is assumed that writing of front surface image data to 135 and writing of back surface image data can be executed in parallel.

First, a data flow when reading an image on a document will be described with reference to FIG. The image reading operation is divided into the following two operations :
(1) Write image data input by the image input devices 133 and 134 into the frame memory 135 ;
(2) The image data stored in the frame memory 135 is read, image processing such as data compression (data conversion) is performed, and the image data is transferred to a storage device (for example, HDD 117, the same applies below) via the data bus. However, when there is no frame memory depending on the device configuration or when the memory capacity of the frame memory is small, it is possible to transfer directly to the data bus without dividing it into two operations as in (1) and (2) above. is there.

  Hereinafter, (1) will be described in the case of surface reading. First, an image signal input from the front surface image input device 133 is input to the image data input IF 138 via the shading processing unit 136. The image data (image signal) is transferred to the frame memory 135 via the DRAM controller 140 by the selector. In the frame memory 135, the input image data is sequentially written and stored.

  Next, (2) will be described. First, the image data stored in the frame memory 135 is transferred to the PCI transfer controller 152 by the selector 151 via the various image data processing units 141 to 145. Then, the transferred data is stored in the storage device by the PCI transfer controller 152 via the PCI data bus. The image data processing units include mask processing units 141 and 146, filter processing units 142 and 147, scaling processing units 143 and 148, area expansion / reduction processing units 144 and 149, and image compression processing units 145 and 150. is there. The selector 151 includes a plurality of image input units and a plurality of image output units, and has a switching function for outputting the input image data to the selected image output unit. Further, the PCI transfer controller 152 outputs the plurality of image data output from the selector 151 to the storage device. At this time, it is possible to set a data capacity and an image data transfer speed necessary for outputting each image data to the storage device.

  In this embodiment, by providing means capable of transmitting and receiving a plurality of data through a single data path such as a PCI bus or USB in the portion for executing image data transfer, the data transfer channel can be expanded relatively easily. In addition, the data transfer can be controlled. It is assumed that the image signals input by the image input devices 133 and 134 have different input start timings, data capacities, image data transfer rates, and the like depending on the physical arrangement of image reading elements such as CCDs. For this reason, the selector 151 and the PCI transfer controller 152 are configured to perform image data transfer processing asynchronously for each piece of image data. In addition to synchronously transferring a plurality of image data at the same time, they are individually transferred in parallel and asynchronously (simultaneously). With this configuration, the image data transfer method can be changed in accordance with the double-sided original reading function, the data transfer speed, and the reading timing.

  FIG. 10 shows an operation flow when reading an image from a document. The operation flow will be described below with reference to FIG. This operation flow is programmed as the scanner application 84, and is executed by the CPU 111 using the platform program 75 such as the SRM 86 or the ECS 95 according to the scanner application 84.

  First, the CPU 111 allows the user to set whether or not to erase the image data in the frame memory 135 after the reading is executed by the operation panel 120 (S1). If “erasing” is set (Y in S2), the data erasing timing (data erasing unit) is set (S3). These settings may be performed in advance or may be performed every time reading is performed. The CPU 132 receives the setting information from the CPU 111 and writes it in the NV-RAM 155. The data erasure timing is the timing at which the image data is erased after the image data transfer, and can be selected by the user from every pixel transfer, every line transfer, every access unit to the frame memory 135, every page unit, etc. The image data is erased at the selected timing (erase unit).

  Next, the CPU 111 causes the operation panel 120 to perform image reading control settings (S4). The user is allowed to set conditions for image reading such as double-sided reading and reading resolution. Then, the CPU 111 passes this control setting content to the CPU 132 and starts reading. Thus, the CPU 132 conveys the document via the control IC 154 and the like, and when the document arrives at a predetermined reading position (Y in S5), the image input devices 133 and (134) start reading (S6). The read image data is stored in the frame memory 135, while the image data is transferred from the frame memory 135 to the storage device via the PCI bus.

  Thereafter, the process waits until image reading and image data transfer of one or more pages of the document are completed (N in S7). When reading and image data transfer is completed (Y in S7), the next page or pages are read. It is confirmed whether a document exists (S8). If there is a next original (Y in S8), the image reading / image data transfer is executed again (S4 to S7). If not (N in S8), the image reading / image data transfer is terminated.

  FIG. 11 shows a more detailed operation flow of the image data transfer described above. Hereinafter, this operation flow will be described. First, when executing image reading (reading an image with an image input device and writing image data to the frame memory) and image data transfer (output from the frame memory to the PCI bus) in parallel, the CPU 111 executes the processing by the CPU 132. The image reading process and the data transfer process, which are programs to be executed, are started. As a result, the image reading process immediately starts reading the image on the document (S11). Then, image reading is continued until reaching a predetermined reading end position on the document, and when the reading position is reached (Y in S12), the image reading operation is ended.

On the other hand, in the data transfer process, firstly, it waits until the condition of the starting image data transfer (S21 is the S21 in N). When the image data transfer start condition is satisfied (Y in S21), data transfer from the frame memory 135 to the image data processing unit such as the image compression units 145 and 150 and the storage device via the PCI bus is started (S22). ). Here, it is assumed that the data transfer start condition is set in advance. For example, the data transfer start condition is “the image reading process has started” or “the number of lines written to the frame memory has reached a predetermined value”. In the former case, the image data is read from the frame memory 135 and transferred to the PCI bus simultaneously with the writing of the image data to the frame memory 135, and in the latter case, the image data is written to the frame memory 135 after several lines are written. Data transfer will be started.

  Subsequently, the image data erasure execution setting in the frame memory 135 is confirmed (S23). If the erasure execution is not set (N in S23), then the image data transfer is continued until the predetermined data transfer amount is reached, and if the data transfer amount is reached (Y in S26), this The operation flow is terminated. On the other hand, if erase execution is set (Y in S23), the image data transfer is continued until the condition for the erase timing is satisfied (until the image data erase unit set in step S3 is reached), and the erase timing is reached. If so (Y in S24), the transferred image data in the frame memory 135 is erased (S25). Such processing is continued until the predetermined data transfer amount is reached. If the data transfer amount is reached (Y in S26), this operation flow is ended.

  As described above, the case where the image data in the frame memory is completely erased almost coincident with the completion of the transfer of the image data to the storage device has been described. The configuration may be such that data is erased.

  Thus, according to this embodiment, the image data temporarily stored in the frame memory, which is a buffer memory in the document image reading means, is erased immediately after the image data is transferred to the storage device. . Further, since it is possible to select whether or not to erase the image data, it is possible to save time required for erasing by not erasing depending on the situation. Further, since the erasing unit for erasing the image data can be selected, when erasing the image data in parallel with the image data compression as described above, a more appropriate erasing unit is selected and the image data erasing time is selected. Can be kept within the compression time.

1 is a configuration diagram of a digital copying machine showing a first embodiment of the present invention. FIG. 1 is an explanatory diagram of a main part of a digital copying machine showing a first embodiment of the present invention. 2 is a timing chart of the main part of the digital copying machine showing the first embodiment of the present invention. 1 is a configuration block diagram of a main part of a digital copying machine showing a first embodiment of the present invention. FIG. 3 is a block diagram showing another configuration of the main part of the digital copying machine showing the first embodiment of the present invention. FIG. 5 is a software configuration diagram of a digital multi-function peripheral showing a second embodiment of the present invention. FIG. 6 is a hardware configuration diagram of a digital multi-function peripheral showing a second embodiment of the present invention. Explanatory drawing of the principal part of a digital multi-functional peripheral showing a second embodiment of the present invention. The block diagram of the configuration of the main part of the digital multi-function peripheral showing the second embodiment of the present invention. FIG. 3 is an operation flowchart of the main part of the digital multi-function peripheral showing an embodiment of the present invention. The other operation | movement flowchart of the digital multifunctional machine principal part which shows one Example of this invention.

Explanation of symbols

110 controller, 111 CPU, 115 ASIC, 116 local memory, 117 hard disk storage device, 120 operation panel, 124 engine unit, 132 CPU, 133 image input device, 134 image input device, 135 frame memory, 145 image compression processing unit, 152 PCI transfer controller, 155 NV-RAM

Claims (5)

An image reading means for reading an image on an original, e Bei and an image memory means for storing one or more image data read by the image reading means, before Symbol image reading means or in said image reading means, Between the image storage means and the image storage means, an image temporary storage means for storing all or part of the read image data, and the image data stored in the image temporary storage means are transferred to the image storage means In an image forming apparatus comprising: an image transfer unit; and a data erasing unit that erases image data stored in the image temporary storage unit.
2. An image forming apparatus according to claim 1, wherein the data erasing unit is configured to end the erasing of the image data almost coincident with the completion of the transfer of the image data to the image storage unit . An image reading means for reading an image on an original, e Bei and an image memory means for storing one or more image data read by the image reading means, before Symbol image reading means or in said image reading means, Between the image storage means and the image storage means, an image temporary storage means for storing all or part of the read image data, and the image data stored in the image temporary storage means are transferred to the image storage means In an image forming apparatus comprising: an image transfer unit; and a data erasing unit that erases image data stored in the image temporary storage unit.
The image forming apparatus according to claim 1, wherein the data erasing unit is configured to erase image data immediately after image data transfer to the image storage unit. The image forming apparatus according to claim 1 or 2, characterized in that it has on whether the selection is configurable erasing image data by said data erasure means. 4. The image forming apparatus according to claim 1, wherein the data erasing unit is configured to select an erasing unit when erasing image data. The image forming apparatus according to claim 3 or 4, the image forming apparatus characterized by comprising operating means for specifying the selection to the user.