JP5168044B2 - Image reading apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an image reading apparatus and an image forming apparatus, and more particularly to an image reading apparatus capable of reading the front and back surfaces of a document and an image forming apparatus including the image reading apparatus.

  In recent years, an image reading apparatus (hereinafter also referred to as a double-sided reading apparatus) in which individual reading units are provided on the front side and the back side of a document has been proposed as an apparatus that can read the front and back sides of a document.

  Unlike a conventional double-sided scanning device that scans both sides by reversing a document with respect to one scanning unit, such a double-sided scanning device does not require a document reversing mechanism, and the document is transported once in a single document. Therefore, it is possible to meet the demands for miniaturization, high speed, and low noise.

  For example, this type of double-sided reading apparatus uses a reading page memory area for storing image data of a read original and an output page memory area for storing image data of an original to be output. When reading the image data, there is one in which the reading page memory area is assigned to store image data on one side of the original and the output page memory area is assigned to store image data on one side of the original ( Patent Document 1).

  As another duplex scanning device, the front and back surfaces of a double-sided document are scanned under individual image scanning conditions set in advance by the user or automatically determined by the duplex image scanning device. (See Patent Document 2).

JP 2006-295546 A JP 2007-81687 A

  However, in Patent Document 1, when reading image data on both sides of an original, a reading page memory area is allocated to store image data on one side of the original, and an output page memory area is assigned to one side of the original. Therefore, it is possible to read the image data of a double-sided original with a small memory capacity. However, an original having a data amount exceeding the memory area (for example, a long document) There has been a problem that there is no possibility of dealing with the case of reading a manuscript or the like, and an abnormal image may occur.

  Further, in Patent Document 2, since the image reading conditions can be set individually for the front and back sides of a double-sided document and the images on the front and back sides can be read, the image quality of the double-sided document is different. Although it is possible to perform optimum double-sided scanning without losing the quality of each, a document (such as a long document) having a size exceeding the memory capacity for storing the read image data can be obtained as in Patent Document 1. There has been a problem that there is no countermeasure for the case of reading and an abnormal image may occur.

  Thus, the size of a document that can be read when reading a double-sided document depends on the maximum storage capacity of a frame memory or the like that temporarily stores image data before image processing or before image output. For this reason, if the capacity of the image memory is simply increased, the scanned image data will not exceed the memory capacity even for a large document such as a long document, and it is possible to avoid the occurrence of abnormal images. It is. However, the case of scanning a long document on both sides is very rare compared to the case of scanning a normal document on one side. If a large-capacity memory is prepared for this rare case, the cost is more than necessary. There was a problem that led to up.

  Therefore, in the case of a long document having a data amount exceeding the memory capacity, the conventional double-sided scanning device forcibly generates a jam at the document conveying unit to stop reading, or the long-sided document itself is read on both sides. However, because it is a rare case, it was not guaranteed to work. However, in the former case, there is a possibility that the document may be damaged, and in the latter case, there is a possibility that an abnormal image may be generated although it is a rare case.

  The present invention has been made in view of the above, and even when a large-sized original such as a long original is read on both sides, the reading operation can be started in the same manner as a normal original. An object of the present invention is to provide an image reading apparatus and an image forming apparatus that can prevent an abnormal operation of the apparatus and an abnormal image from occurring by automatically stopping the reading operation before this occurs.

In order to solve the above-described problems and achieve the object, the image reading apparatus of the present invention has a first storage area for storing data on the front side of the document and a second storage area for storing the back side of the document. A primary storage means, a double-sided reading means for performing double-sided reading for reading images on the front and back sides of the document in a single scan, a maximum document size that can be stored in the primary storage means by the double-sided scanning, and An original size comparing means for comparing the size, and the surface of the read original when the size of the read original is smaller than the maximum original size by the original size comparing means after the double-sided reading is started. Is stored in the first storage area, and back side data is stored in the second storage area. A storage for storing the data of the read original in a combined storage area including the first storage area and the second storage area when it is determined that the size of the read original is larger than the maximum original size. After the start of double-sided scanning with the control means, the combined storage area of the primary storage means stores the size of the original read by the original size comparing means when determined to be larger than the maximum original size. and the stored data amount detecting means for detecting the amount of data are the amount of memory data stored in the binding storing area of the detected said primary memory means by said memory data amount detecting means, the maximum storage capacity of said primary storage means The double-sided scanning operation is continued until the detected storage data amount reaches the maximum storage capacity. It said control means for controlling the double-sided reading means, characterized by comprising to.

  An image forming apparatus according to the present invention includes the image reading apparatus.

  According to the present invention, when it is detected that the size of the original exceeds the maximum original size that can be stored in the primary storage means after the double-sided reading operation of the original is started, the maximum storage capacity of the primary storage means is read. Since the reading operation is stopped after the operation is continued, the storage capacity of the primary storage means is not exceeded, and it is possible to prevent the abnormal operation of the apparatus and the occurrence of an abnormal image.

  Exemplary embodiments of an image reading apparatus and an image forming apparatus according to the present invention are explained in detail below with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is an explanatory diagram illustrating the overall configuration of an image forming apparatus including the image reading apparatus according to the first embodiment. The image forming apparatus 10 shown in FIG. 1 shows an example used in a digital multifunction peripheral, and roughly includes an image reading unit 20, a system controller 30, an image forming unit 70, and the like. The unit 40, the FAX unit 50, and the I / F unit 60 are connected.

  The image reading unit 20 includes a double-sided reading mechanism as double-sided reading means that can read the front and back sides of a document. This double-sided reading mechanism performs scanning exposure by moving an exposure lamp 23 movable along the document table 22 along the document table 22 on the surface of the document 21 (here, the lower surface in the figure), and the reflected light is transmitted. The light is reflected by mirrors 24a, 24b, and 24c and subjected to photoelectric conversion by a CCD (image sensor) 25 to obtain an electric signal corresponding to the intensity of light. An IPU (image processing unit) 26 performs shading correction on the electrical signal from the CCD 25 and performs analog / digital conversion (A / D conversion) to obtain an 8-bit digital signal. The IPU 26 further sends an image signal subjected to image processing such as scaling processing and dither processing to the system controller 30 described later together with an image synchronization signal.

  Further, along the back surface of the document 21 (here, the upper surface in the figure), the back surface lamp 22 is moved in the sub-scanning direction to perform scan exposure, and the reflected light reflected on the back surface is contact image sensor (CIS). : Contact Image Sensor) 28 is imaged. The electrical signal from the CIS 28 is also sent to the system controller 30 together with the image synchronization signal as an image signal that has been subjected to image processing in the IPU 26 as described above.

  As described above, in FIG. 1, the reading mechanism side is moved with respect to the document 21 on the document table 22 to read the image, but the double-sided reading mechanism is arranged in the middle of the document transport path, A mechanism for reading a double-sided image while the document is transported once may be used. A document size detection unit 19 serving as a document size comparison unit in the image reading unit 20 detects a document size to be read, and a primary storage unit that stores the image data on both sides read by the duplex reading mechanism for each frame. Is compared with the maximum document size that can be stored in a frame memory (such as DRAM 305 in FIG. 9), and the scanner controller 29 is notified when the document size to be read is larger. This is to determine whether or not the document to be read is a document size that can be read on both sides. Furthermore, in order to execute the reading process of the image reading unit 20, the scanner control unit 29 acquires detection data from each sensor, performs driving control on each driving unit, and sets various parameters on the IPU 26. This is for setting.

  1 includes a system control unit 33 as a control unit, a storage unit 32 including a primary storage unit, a selector unit 31, and the like, and includes a FAX unit 50, an I / F unit 60, a display unit. Image data, control signals, and the like are exchanged between the input unit and the operation display unit 40 as the setting operation designation unit.

  The system control unit 33 detects an input state to the operation display unit 40 by the operator, and sets various parameters in the image reading unit 20, the storage unit 32, the image forming unit 70, the FAX unit 50, and the I / F unit 60. Process execution instructions and the like are performed by communication. Further, the system control unit 33 displays the state of the entire system on the operation display unit 40, and an instruction to the system control unit 33 is made by a key input of the operation display unit 40 by the operator.

  The storage unit 32 normally stores image data of a document input from the IPU 26, and is used for a copy application such as repeat copy or rotation copy. The storage unit 32 is also used as a buffer memory that temporarily stores binary image data from the FAX unit 50. Further, the storage unit 32 is also used as means for storing unique information of the image reading unit 20 and the image forming unit 70. Data storage instructions to the storage unit 32 are given by the system control unit 33.

  The selector unit 31 changes the state of the selector in accordance with an instruction from the system control unit 33, and sets the image data source for image formation as the image forming unit 70, the storage unit 32, the FAX unit 50, and the I / F unit 60. Select one of these to send it out.

  In response to an instruction from the system control unit 33, the FAX unit 50 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. The data transferred from the telephone line to the FAX unit 50 is restored to binary image data, sent to the writing unit 71 of the image forming unit 70, and visualized.

  The I / F unit 60 transmits data stored in the storage unit 32 to the outside or receives data from the outside and stores it in the storage unit 32 according to an instruction from the system control unit 33. Further, the I / F unit 60 transmits and receives commands according to instructions from the system control unit 33.

  1 includes a writing unit 71 that writes an image based on the image data read by the image reading unit 20, a plotter control unit 72 that controls the image forming unit 70, and the formed image. It is composed of a transfer mechanism, which will be described later, that transfers to transfer paper. This transfer mechanism exposes a constant rotating photoreceptor 75 uniformly charged by the charging charger 74 with a laser beam modulated by image data from the writing unit 71. By exposure, an electrostatic latent image is formed on the photosensitive member 75, and is developed with toner by the developing device 76, whereby a visualized toner image is obtained.

  The transfer paper on which the toner image is transferred is stored in the paper feed tray 73, and is fed and conveyed from the paper feed tray 73 by the paper feed roller 77, and the transfer paper waiting on the registration roller 78 is transferred to the photoconductor 75. Then, it is transported to the transfer position while timing. The transfer paper is electrostatically transferred with the toner image formed on the photoconductor 75 by the transfer charger 79 and separated from the photoconductor by the separation charger 80. Thereafter, the toner image transferred onto the transfer sheet is heated and fixed by the fixing device 81 and discharged onto the discharge tray 83 by the discharge roller 82. On the other hand, the toner image remaining on the photosensitive member 75 after electrostatic transfer is removed by pressing the cleaning device 84 against the photosensitive member 75, and the static electricity on the photosensitive member 75 is discharged by the discharging charger 85. The plotter control unit 72 of the image forming unit 70 acquires detection information from various sensors and controls a drive motor and the like in order to execute the above image forming process.

  FIG. 2 is a plan view of the document and the document table in the image reading unit of FIG. 1 as viewed from above. As shown in FIG. 2, the image reading of the document 21 on the document table 22 is performed by reading the entire image of the document 21 by moving the reading position in the sub-scanning direction while repeating the reading operation in the main scanning direction. Can do.

  FIG. 3 is a signal waveform diagram output from the IPU of the image reading unit in FIG. The top frame gate signal (/ FGATE) in FIG. 3 is a signal representing an image effective range for the image area in the sub-scanning direction in FIG. 2, and image data while this signal is at a low level (low active). Valid. The frame gate signal (/ FGATE) is asserted or negated at the falling edge of the second line synchronization signal (/ LSYNC). This line synchronization signal (/ LSYNC) is asserted for a predetermined number of clocks at the rising edge of the third image 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 period of the image synchronization signal (PCLK), and is divided by 400 dpi from the black triangle portion of FIG. The image data is sent as raster format data starting from the black triangle in FIG. Further, the sub-scanning effective range of image data is usually determined by the transfer paper size.

  FIG. 4 is a block diagram of the configuration in the storage unit of the system controller of FIG. The storage unit 32 includes an image input / output unit (DMAC) 321 as a storage data amount detection unit, an image memory 322 as a primary storage unit, a memory control unit 323, an image transfer unit (DMAC) 324, and a code transfer unit (DMAC) 325. , Compression / decompression unit 326, HDD controller 327, HD 328, and the like.

  The image input / output unit (DMAC) 321 includes a CPU and logic, and communicates with the memory control unit 323 to receive a command, perform operation setting according to the command, and notify its own state. Send status information for. 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 323 along with the memory access signal as needed. When an image output command is received, the image data from the memory control unit 323 is output in synchronization with the output image synchronization signal.

  The image memory 322 stores image data and is composed of a semiconductor storage element such as a DRAM. In this case, the total amount of memory is 4 MB for A3 size of binary image data, 4 MB for electronic sort storage, 6 MB for data transfer work area, and 2 MB for image data management area in the case of 400 dpi. Yes. Reading control and writing control for the image memory 322 are performed by the memory control unit 323.

  The memory control unit 323 includes a CPU and a logic, communicates with the system control unit 33, receives a command, sets an operation according to the command, and informs the status of the image memory 322. Send information. The operation commands received by the memory control unit 323 from the system control unit 33 include image input, image output, compression, decompression, etc. The image input and image output commands are sent to the image input / output unit (DMAC) 321 and are related to compression. Are transmitted to the image transfer unit (DMAC) 324, the code transfer unit (DMAC) 325, and the compression / decompression unit 326.

  The image transfer unit (DMAC) 324 is composed of a CPU and logic, and communicates with the memory control unit 323 to receive a command, set an operation according to the command, and notify its own state. Send status information. When the image transfer unit (DMAC) 324 receives a compression command, it outputs a memory access request signal to the memory control unit 323. When the memory access permission signal is active, it receives the image data and transfers it to the compression / decompression unit 326. To do. 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 unit (DMAC) 325 is composed of a CPU and logic, communicates with the memory control unit 323, receives a command, performs operation settings according to the command, and informs its own state. Send status information. When the code transfer unit (DMAC) 325 receives a decompression command, it outputs a memory access request signal to the memory control unit 323. When the memory access permission signal is active, it receives image data and compresses / decompresses 326. Forward to. 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 descriptor access operation in the DMAC (Direct Memory Access Controller) will be described later.

  The compression / decompression unit 326 is configured by a CPU and logic, communicates with the memory control unit 323, receives a command, performs operation setting according to the command, and provides status information for notifying its own state. Send. The binary data is processed by the MH encoding method.

  The HDD controller 327 is composed of a CPU and logic, communicates with the memory control unit 323, receives a command, performs operation settings according to the command, and transmits status information for notifying its own state. To do. The HDD controller 327 reads the status of the HD 328 or transfers data. The HD 328 is a hard disk that is a secondary storage device.

  FIG. 5 is a block diagram illustrating a detailed configuration of the memory control unit of FIG. The memory control unit 323 in FIG. 5 includes an input / output image address counter unit 3231, a transfer image address counter unit 3232, a line setting unit 3233, a difference calculation unit 3234, a difference comparison unit 3235, an address selector unit 3236, an arbiter unit 3237, a request mask. Part 3238, an access control circuit 3239, and the like.

  The input / output image address counter unit 3231 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. The address is initialized once at the start of memory access.

  The transfer image address counter unit 3232 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 transfer image data is stored. The address is initialized once at the start of memory access.

  The line setting unit 3233 is a difference comparison unit 3235 in the case of using a semiconductor memory as a buffer at the time of image input, and system-controls a value for comparing the input processing line output from the difference calculation unit 3234 and the difference result of the transfer line. This is set from the unit 33. An arbitrary value can be set.

  The difference calculation unit 3234 subtracts the number of input / output processing lines output from the image input / output unit (DMAC) 321 from the number of transfer processing lines output from the compression / decompression unit 326 when inputting an image, and outputs the result to the difference comparison unit 3235. To do.

  The difference comparison unit 3235 compares the number of difference lines output by the difference calculation unit 3234 and the setting value output by the line setting unit 3233 when inputting an image, and outputs an error signal when the number of difference lines = the setting value. When the number of difference lines = 0, the transfer request mask signal of the comparison result output to the arbiter unit 3237 is made active. In other cases, or in a state where the input / output image is not in operation, no active is output.

  The address selector unit 3236 is a selector that is selected by the arbiter unit 3237, and selects either the input image or the transfer image address.

  The arbiter unit 3237 outputs a transfer memory access permission signal for accessing the compression / decompression unit 326. When the address comparison signal is active and the input / output memory access request signal is inactive, a transfer memory access permission signal is output.

  The request mask unit 3238 masks the transfer memory access request signal for accessing the compression / decompression unit 326 based on the comparison result from the processing line number comparator, and stops the transfer process. is there.

  The access control circuit 3239 divides an input physical address into a row address and a column address corresponding to a DRAM which is a semiconductor memory, and outputs it to an 11-bit address bus. Further, in accordance with an access start signal from the arbiter unit 3237, a DRAM control signal (RAS, CAS, WE) is output.

  As described above, the storage unit 32 of the system controller 30 is configured as shown in FIG. 4, and the memory control unit 323 of the storage unit 32 of FIG. 4 is further configured as shown in FIG. In other words, the overall operation of the storage unit 32 relates to image input and data storage, and image data is written to and read from a predetermined image area of the image memory 322 by the image transfer unit (DMAC) 324 according to instructions from the system control unit 33. To do. At this time, the image transfer unit (DMAC) 324 counts the number of image lines.

  Also, the memory control unit 323 of the storage unit 32 in FIG. 4 is initialized by an image input instruction from the system control unit 33, enters a wait state for image data, and operates the image reading unit 20 to operate the storage unit 32. The image data is input to.

  The image data input to the storage unit 32 is once written in the semiconductor memory. The number of processing lines of image data written in the semiconductor memory is counted by the image input / output unit (DMAC) 321 of the storage unit 32 and input to the memory control unit 323. The compression / decompression unit 326 of the storage unit 32 receives the image transfer command and outputs a transfer memory access request signal to the memory control unit 323, but the request signal is masked by the request mask unit 3238 of the memory control unit 323. Actual memory access is not performed. When one line of input data from the image input / output unit (DMAC) 321 is completed, the mask of the transfer memory access request signal is released, the semiconductor memory is read, and the transfer operation of the image data to the compression / decompression unit 326 is performed. Be started. Further, the difference calculation unit 3234 calculates the difference between the two processing lines even during the operation, and if the difference becomes “0”, the transfer memory access request signal is masked so that the address is not overtaken.

  FIG. 6 is a software configuration diagram of an image forming apparatus using the image reading apparatus according to the first embodiment. Here, as the image forming apparatus 10, a multi-function machine in which the functions of each apparatus such as a printer, a copy, a facsimile, and a scanner are housed in one housing is used. As shown in FIG. 6, the image forming apparatus 10 includes a software group 100, a multifunction machine starting unit 180, hardware resources 171 such as a scanner and a facsimile, a monochrome laser printer (B & W LP) 172, a color laser printer (Color LP). ) 173 including hardware resources 170.

  The software group 100 includes an application layer 110 and a platform 140. The multi-function device 10 can centrally process processes commonly required for each application on the platform 140.

  The application layer 110 has a program for performing processing unique to each user service related to image formation, such as a printer, copy, fax, and scanner. The application layer 110 includes a printer application 111 that is a printer application having a page description language (PDL), PCL, and host script (PS), a copy application 112 that is a copy application, and a fax application 113 that is a fax application. And a scanner application 114 which is a scanner application.

  The platform 140 interprets a processing request from the application 110 and generates an acquisition request for the hardware resource 170, and manages one or more hardware resources 170 to acquire the acquisition request from the control service 120. SRM (system resource manager) 129 for arbitrating, a handler layer 130 for managing hardware resources 170 in response to an acquisition request from the SRM 129, and a general-purpose OS.

  The control service layer 120 includes a plurality of service modules, and includes an NCS (network control service) 121, a DCS (delivery control service) 122, an OCS (operation panel control service) 123, and an FCS (fax control service) 124. ECS (engine control service) 125, MCS (memory control service) 126, UCS (user information control service) 127, SCS (system control service) 128, and the like. The platform 140 includes an API 150 that can receive a processing request from the application 110 using a predefined function.

  The OS is a general-purpose operating system such as UNIX (registered trademark), and executes software of the application layer 110 and the platform 140 in parallel as processes.

  The process of the NCS 121 provides a service that can be used in common for applications that require network I / O. Data received from the network side according to each protocol is distributed to each application, or data from each application. Mediating when sending to the network side.

  For example, the NCS 121 controls data communication with a network device connected via a network using HTTP (HyperText Transfer Protocol) by HTTP (HyperText Transfer Protocol).

  The process of the DCS 122 performs control such as distribution of stored documents. The process of the OCS 123 controls an operation panel serving as information transmission means between the operator and the main body control. The FCS124 process provides APIs to perform fax transmission / reception using the PSTN or ISDN network from the application layer 110, registration / quotation of various fax data managed in the backup memory, fax reading, fax reception printing, etc. To do.

  The process of the ECS 125 controls engine units such as the hardware resource 171, the monochrome laser printer 172, and the color laser printer 173. The process of the MCS 126 performs memory control such as acquisition and release of memory and use of the HDD. The UCS 127 manages user information.

  The process of the SCS 128 performs processing such as application management, operation unit control, system screen display, LED display, hardware resource management, and interrupt application control.

  The SRM 129 process controls the system and manages the hardware resources 170 together with the SCS 128. For example, the process of the SRM 129 performs execution control in accordance with an acquisition request from an upper layer using the hardware resource 170 such as the black and white laser printer 172 and the color laser printer 173.

  Specifically, the process of the SRM 129 determines whether the requested hardware resource 170 is available (whether it is not used by another acquisition request). The upper layer is notified that the hardware resource 170 is available. Further, the process of the SRM 129 performs scheduling for using the hardware resource 170 in response to an acquisition request from an upper layer, and the request contents (for example, paper conveyance and image forming operation by the printer engine, memory allocation, file generation, etc.) Has been implemented directly.

  The handler layer 130 includes an FCUH (fax control unit handler) 131 that manages an FCU (fax control unit), which will be described later, and an IMH (image memory handler) 132 that allocates memory for the process and manages the memory allocated to the process. have. The SRM 129 and the FCUH 131 make a processing request for the hardware resource 170 by using an engine I / F 160 that can transmit a processing request for the hardware resource 170 by a predefined function.

  The multifunction device activation unit 180 is executed first when the multifunction device as the image forming apparatus 10 is turned on, and activates the application layer 110 and the platform 140. For example, the multifunction device activation unit 180 reads the programs of the application layer 110 and the platform 140 from the HDD 208 (see FIG. 7) and transfers each read program to the memory area of the MEM-P 202 (see FIG. 7). To do.

  FIG. 7 is a hardware configuration diagram of the image forming apparatus of FIG. The MFP as an image forming apparatus includes a controller board 200, an operation panel 210, a PCI bus, an FCU 220, a USB device 230, an IEEE 1394 device 240, and an engine unit {scanner engine (“image reading” Device ") and printer engine)} 250.

  The controller board 200 includes a CPU 201 as control means, a MEM-P (system memory) 202, an NB (north bridge) 203, an SB (south bridge) 204, an ASIC 205, and a MEM-C (primary storage means). A local memory (primary storage unit) 207 and an HDD (secondary storage unit) 208 as secondary storage means are provided.

  The CPU 201 is connected to the MEM-P (system memory) 202 and the ASIC 206 via the NB 203. As described above, by connecting the CPU 201 and the ASIC 20 via the NB 203, it is possible to cope with the case where the interface of the CPU 201 is not disclosed. The ASIC 206 and the NB 203 are connected via an AGP (Accelerated Graphics Port) 205. As described above, in order to control execution of one or more processes forming the application layer 5 and the platform 6 in FIG. 1, the ASIC 206 and the NB 203 are connected via the AGP 205 instead of the low-speed PCI bus to prevent performance degradation. It is out.

  The CPU 201 controls the entire multifunction machine. The CPU 201 starts and executes the NCS 121, DC 122, OCS 123, FCS 124, ECS 125, MCS 126, UCS 127, SCS 128, SRM 129, IMH 130, and FCUH 131 of FIG. 6 as processes on the OS, and also forms the application layer 110. The copy application 112, the fax application 113, and the scanner application 114 are activated and executed.

  The NB 203 is a bridge for connecting the CPU 201, the MEM-P (system memory) 202, the SB 204, and the ASIC 206. A MEM-P (system memory) 202 is a memory used as a drawing memory of the multifunction peripheral 100. The SB 204 is a bridge for connecting the NB 203 to a ROM, a PCI bus, and peripheral devices. A MEM-C (local memory) 207 is a memory used as a copy image buffer and a code buffer.

  The ASIC 206 is an IC for image processing applications having hardware elements for image processing. The HDD 208 is a storage for storing image data, document data, programs, font data, forms, and the like. The operation panel 210 is an operation unit that accepts an input operation from the operator and performs display for the operator. The operation panel 210 includes a display unit, an input unit, a setting operation designation unit, and the like.

  The operation panel 210 is connected to the ASIC 206 of the controller board 200. Further, the FCU 220, the USB device 230, the IEEE 1394 device 240, and the engine unit 250 are connected to the ASIC 206 of the controller board 200 via a PCI bus.

  FIG. 8 is a diagram for explaining the function of the ASIC of FIG. As shown in FIG. 8, the ASIC 206 has a DMA controller function for transferring an image, and is connected to the scanner engine and printer engine of the engine unit 250 through the PCI bus. The ASIC 206 has two channels for the video input DMA controller and one channel for the video output DMA controller, which are assigned different PCI bus addresses. The video of the scanner input 1, the scanner input 2, and the plotter output of the engine unit 250. Data transfer can be performed in parallel. The video input DMA controller and video output DMA controller of the ASIC 206, the MEM-C (local memory) 207 as a primary storage unit, and the HDD 208 as a secondary storage unit constitute the storage unit (primary storage means) 32 in FIG. Has been.

  When transferring the double-sided image read by the scanner engine of the engine unit 250 to the MEM-C (local memory) 207, the IMH 132 secures the memory for the transfer image size in the MEM-C 207 in response to the process request from the SRM 129. The transfer image sizes Xw and Yw and the secured memory address are set in the video input DMA controller, thereby enabling transfer.

  FIG. 9 is a diagram showing an example of functional blocks of the engine unit that realizes reading of the front and back sides of a double-sided document. The engine unit 250 includes a first image input unit (front) 301, a second image input unit (back) 302, a first shading unit (front) 303, a second shading unit (back) 304, a DRAM 305, A first gradation processing unit 306, a second gradation processing unit 307, a GAVD (output unit) 308, and an image data control IF controller 400 are provided.

  The first image input unit (front) 301 and the second image input unit (back) 302 are double-sided reading means such as a CCD or CIS. The first image input unit (front) 301 reads the image data on the front side of the double-sided document, and the second image input unit (back) 302 reads the image data on the back side, thereby reading the front and back sides of the double-sided document. Is realized.

  The image data control IF controller 400 is directly controlled by the CPU 201. The image data control IF controller 400 includes a first input IF (front) 401, a second input IF (back) 403, a DRAM controller 402, a mask unit 404, a filter unit 405, a scaling unit 406, an area expansion / reduction unit 407, Image compression unit 408, blank page detection unit 409, selector 414, PCI transfer controller 415, PCI_IF 416, image expansion unit 417, area expansion / reduction unit 418, print composition unit 419, output IF 420, gradation processing data input IF 421, GAVD_IF 423, status A register 424, a control register 425, a CPU_IF 426, a control IC 427, a host IF 428, an image input controller 429, and the like are provided.

  The image data control IF controller 400 is connected to the PCI bus via the PCI_IF 416, and data output to the storage unit and data input from the storage unit are possible via the PCI bus. The DRAM 305 is a frame memory serving as a primary storage unit for temporarily storing image data input from the first image input unit (front) 301 and the second image input unit (back) 302. The DRAM 305 is used to adjust the timing of image input on the front and back surfaces and the data transfer rate to the PCI bus when reading both sides. The DRAM controller 402 is configured to execute image data writing to the DRAM 305 and image data reading from the DRAM 305 in parallel. Further, the DRAM controller 402 is configured to execute the writing of the front surface image and the writing of the back surface image in parallel to the DRAM 305 when executing the double-sided reading of the double-sided document. The selector 414 includes a plurality of image input units and a plurality of image output units, and has a function of performing image data switching for outputting input image data to an arbitrary image output unit. The PCI transfer controller 415 has a function of outputting a plurality of image data output from the selector 414 to the storage unit via the PCI bus. The selector 414 and the PCI transfer controller 415 can set a data capacity and an image data transfer speed necessary for outputting each image data to the storage unit.

  Next, a double-sided image reading operation in which the engine unit 250 reads a double-sided document and transfers it to the storage unit will be described with reference to FIG. The double-sided image reading operation includes (1) an operation (image reading) for storing image data input by the double-sided document reading device (first image input unit (front) 301, second image input unit (back) 302, etc.) in the DRAM 305. Process) and (2) an operation (image data transfer process) of reading image data stored in the DRAM 305 and transferring it to the storage unit via the PCI bus. The operations (1) and (2) will be described in the case of reading image data on the surface of the document.

  First, the operation (1) will be described. The image data input from the first image input unit (table) 301 is input to the first input IF 401 via the first shading unit (table) 303. The image data input to the first input IF 401 is transferred to the DRAM controller 402. The DRAM controller 402 sequentially writes and stores the transferred image data in the DRAM 305.

  Next, the operation (2) will be described. The image data stored in the DRAM 305 is sequentially read out by the DRMA controller 402, and the image data processing block (mask unit 404, filter unit 405, scaling unit 406, area expansion / reduction unit 407, image compression unit 408) is read. Then, the data is transferred to the PCI transfer controller 415 by the selector 414. The PCI transfer controller 415 transfers input image data to the storage device via the PCI bus.

  In the memory control method of the DRAM 305, when reading a normal double-sided original, the DRAM 305 is divided into first and second memory areas, the first memory area is used for surface image data, and the second memory is used. The area is used for back image data. Input / output of data on the front and back surfaces of the DRAM 305 as the frame memory can be performed independently.

  In the case of reading a long document, the first and second memory areas of the DRAM 305 are used as one memory area and operated in the ring buffer mode, thereby realizing reading of the long document. Yes.

  As described above, the image forming apparatus 10 according to the present embodiment can transmit and receive a plurality of data through the data path of the PCI bus, and data transfer can be performed by relatively increasing the number of data transfer channels. It is the structure which can perform control of.

  The image forming apparatus using the image reading apparatus according to the first embodiment is configured as described above, and the operation thereof will be described below. FIG. 10 is a flowchart for explaining a basic document reading operation according to the first embodiment.

  First, as shown in FIG. 1, the operator designates double-sided reading or single-sided reading before reading a document (step S100). When double-sided scanning is designated, the double-sided scanning mechanism shown in FIG. 1 is used to start the reading process for the front and back sides of the document 21 (step S101), start transporting the document (step S102), and both sides of the document. Reading is started (step S103). In the first embodiment, the double-sided reading mechanism is provided in the middle of the document transport path, and when the document transport is started, the document double-sided scanning operation is also started. That is, the input of the front side image data from the first image input unit (table) 301 to the DRAM 305, the input of the back side image data from the second image input unit (back) 302 to the DRAM 305, and the DRAM 305 shown in FIG. Are processed by the image data control IF controller 400, and the image is transferred via the PCI bus.

  In step S104, it is determined whether or not the reading of the original and the image processing have been completed. If the processing has been completed, the read original is discharged to a discharge tray. Then, the presence / absence of the next original is confirmed (step S106), and if the read original remains, the process returns to step S100, and the original reading operation is repeated.

  If single-sided reading is selected in step S100, after single-sided reading is performed, the process proceeds to step S104, and the processes from step S104 to step S106 described above are performed.

  FIG. 11 is a flowchart for explaining the subroutine for starting the double-sided reading operation of FIG. 10, which is a characteristic operation according to the first embodiment. When the double-sided reading operation is started, first, the first image input unit (table) 301 in FIG. 9 is stored from the top address of the first half area for the front image of the DRAM 305 via the DRAM controller 402. Further, the second image input unit (back side) 302 of FIG. 9 stores the data from the start address of the second half area for the back side image of the DRAM 305 via the DRAM controller 402.

  After the double-sided reading is started, the size of the original to be read is detected by the original size detecting unit 19 in FIG. 1 (step S200), and both sides are stored in the frame memory (DRAM 305) of the storage unit 32 mounted on the image forming apparatus 10. It is compared whether or not it is larger than the maximum document size that can store image data, and based on the comparison result, it is determined whether or not the document size exceeds the memory capacity (step S201).

  If it is found that the size of the document to be read is larger than the maximum document size that can be stored in the frame memory (DRAM 305) of the storage unit 32 after the duplex scanning is started, that is, the document to be scanned is stored in the memory for duplex scanning. If it is determined that the document size does not fit within the document, the CPU 201 conveys the document to the document length position that is the maximum storage capacity of the memory and continues reading (step S202), and then performs document conveyance and reading operations. Stop (step S203).

  The CPU (201) of the system control unit 33 in FIG. 1 displays a message “Double-sided scanning is specified, but a long document is installed” on the display panel of the operation display unit 40. A warning is given that a document size that cannot be read on both sides is set (step S204). In this embodiment, a display panel is used to notify the operator by displaying characters (warning). However, the notification is not limited to character display, and notification may be made by flashing sound or light.

  In addition to the above warning message, the CPU 201 reads “Specify processing from the next operation. A: Finish reading. B: Change to single-sided reading and read. The operation selection message “C: Designate a readable document size” is displayed, and the operator selects a process after the operation is stopped (step S205).

  The operator sees this message display and selects one of A, B, and C (step S206). If A is selected, the CPU 201 ends the reading operation (step S207), and the maximum memory is selected. The image data in the memory read to the capacity is discarded (step S208).

  If the operator selects B, the CPU 201 discards the back side data in the memory (step S209), switches to the front long reading mode (step S210), restarts the reading operation, and performs image processing and transfer. Is performed (step S211). Here, the single-sided reading is described as the front side reading, but conversely, the front side data may be discarded in step S209 and the back side long reading mode may be switched in step S210.

  Furthermore, when the operator selects C, the CPU 201 displays an input screen for the designated document size from the operator on the display panel of the operation display unit 40 (step S212). When the operator inputs a designated document size from this screen (step S213), image processing is performed and transferred as a document of a designated size using the image data read up to the maximum memory capacity (step S214). In step S201, when the document size to be read is smaller than the maximum document size that allows double-sided image data to be stored in the frame memory (DRAM 305) of the storage unit 32 mounted on the image forming apparatus 10. When the document size does not exceed the prescribed memory capacity, a normal reading operation and image processing are performed (step S215). In this way, after the reading start subroutine process of FIG. 11 is performed, the process returns to FIG.

  As described above, according to the image forming apparatus using the image reading apparatus according to the first embodiment, the operator designates the double-sided reading mode, starts conveying the document, and after reading starts, Even when it is found that the document size is a long document exceeding the maximum document size that allows double-sided image data to be stored in the DRAM 305, the CPU 201 uses the image input / output unit (DMAC) 321 serving as a storage data amount detection unit to execute the DRAM 305. The reading operation on both sides is continued until the maximum storage capacity is reached, and the reading operation is stopped. For this reason, it is possible to prevent abnormal operations and abnormal images from occurring. In addition, after the reading operation is stopped, a warning message or a selection message is displayed, and if there is an instruction from the operator, the post-processing is performed according to the instruction, so that already read image data can be used effectively and the operator The reading process can be performed according to the request.

  In particular, since the message is displayed, the operator can notice the occurrence of the abnormal operation, and further, by performing the selection message display and allowing the operator to select, the countermeasure method after the abnormal operation occurs is also performed according to the operator's request. be able to.

  Even if the operator sets a long document exceeding the maximum document size that can store double-sided image data in the memory and sets a double-sided scanning mode, the abnormal operation will occur. The system can be automatically stopped before occurrence to prevent abnormal images from occurring, and the setting mode can be changed during the operation such as changing to the single-sided reading mode and continuing the reading operation. The law becomes possible.

(Second Embodiment)
In the first embodiment, a message is displayed after it is determined that the document is a long document exceeding the maximum document size that can store double-sided image data in the memory, and the operator watches the message. Although the selection has been made, the second embodiment is characterized in that it is possible to set in advance how to deal with a long document after it has been read.

  Since the configuration of the image reading apparatus according to the second embodiment and the image forming apparatus using the same are the same as those of the first embodiment, description of the configuration is omitted. FIG. 12 is a flowchart for explaining the operation according to the second embodiment. The flowchart of FIG. 12 shows the operation after the connector “1” in the operation flow of FIG. 11 according to the first embodiment, and the description of the operation before “1” is omitted.

  In the second embodiment, the operator designates in advance using the operation display unit 40 as setting operation designation means from among the operation designations A, B, and C described in the first embodiment, and reads When it is determined that the document is a long document exceeding the maximum document size that can store the double-sided image data in the memory after the start, the operation is performed according to the setting contents. For example, in step S203 in FIG. 11, after the document conveyance and reading operations are stopped, the process proceeds to step S300 in FIG. 12, and the CPU 201 confirms the preset setting information and is designated in advance. It is determined whether the option is A, B, or C (step S300).

  If A is designated in advance, the CPU 201 terminates the reading operation (step S301), and discards the image data in the memory read up to the maximum memory capacity (step S302).

  If the operator has designated B in advance, the CPU 201 discards the back side data in the memory (step S303), switches to the front long reading mode (step S304), restarts the reading operation, and Processing and transfer are performed (step S305). Here, the single-sided reading is described as the front side reading, but conversely, the front side data may be discarded in step S303, and the back side long reading mode may be switched in step S304.

  Further, when the operator designates C in advance, the CPU 201 performs image processing on the image data in the memory as a document of a predesignated size and transfers it (step S306). Thus, after performing the process of FIG. 12, it returns to FIG. 10 and the process below step S104 is performed.

  As described above, according to the image forming apparatus using the image reading apparatus according to the second embodiment, the operator designates the double-sided reading mode, starts conveying the document, and after reading starts, Even when it is found that the document size is a long document exceeding the maximum document size that allows double-sided image data to be stored in the DRAM 305, the CPU 201 uses the image input / output unit (DMAC) 321 serving as a storage data amount detection unit to execute the DRAM 305. The reading operation on both sides is continued until the maximum storage capacity is reached, and the reading operation is stopped. For this reason, it is possible to prevent abnormal operations and abnormal images from occurring. In addition, after the reading operation is stopped, post-processing is performed in accordance with the setting contents set in advance or the setting contents instructed in advance by the operator, so that the image data that has already been read can be used effectively and at the request of the operator A corresponding reading process can be performed.

  In particular, since the operator can set the countermeasure after the reading operation is stopped in advance using the operation display unit 40, the length exceeding the maximum document size that allows the operator to store double-sided image data in the memory. Even if you make a setting mistake such as setting a length document on the image reading device and specifying the double-sided reading mode, post-processing is performed according to the contents set in advance, eliminating the need for cumbersome operations and allowing quick processing. .

  As described above, the image reading apparatus according to the present invention and the image forming apparatus including the image reading apparatus are image input / output devices such as a digital copying machine, a facsimile, a printer, a scanner, and a network file server, or a plurality of functions among them. Suitable for multi-function machines equipped with

1 is a configuration explanatory diagram illustrating an overall configuration of an image forming apparatus including an image reading apparatus according to a first embodiment. FIG. 2 is a plan view of a document and a document table in the image reading unit of FIG. 1 viewed from above. It is a signal waveform diagram output from IPU of the image reading part of FIG. FIG. 2 is a configuration block diagram in a storage unit of the system controller of FIG. 1. FIG. 5 is a block diagram illustrating a detailed configuration of a memory control unit in FIG. 4. 1 is a software configuration diagram of an image forming apparatus using an image reading apparatus according to a first embodiment. FIG. 7 is a hardware configuration diagram of the image forming apparatus in FIG. 6. It is a figure explaining the function of ASIC of FIG. It is a figure which shows an example of the functional block of the engine part which implement | achieves the reading of the surface of a double-sided document, and a back surface. 3 is a flowchart for explaining a basic document reading operation according to the first embodiment. 11 is a flowchart for explaining a subroutine for starting a double-sided reading operation in FIG. 10. It is a flowchart explaining the operation | movement concerning 2nd Embodiment.

Explanation of symbols

10 Image forming device (multifunction machine)
19 Document Size Detection Unit 20 Image Reading Device 25 CCD
26 IPU
28 CIS
DESCRIPTION OF SYMBOLS 29 Scanner control part 30 System controller 31 Selector part 32 Memory | storage part 33 System control part 40 Operation display part 70 Image formation part 71 Writing part 72 Plotter control part 110 Application layer 170 Hardware resource 140 Platform 200 Controller board 201 CPU
202 MEM-P (system memory)
203 NB (North Bridge)
204 SB (South Bridge)
205 AGP
206 ASIC
207 MEM-C (local memory)
208 HDD
210 Operation panel 220 FCU
230 USB device 240 IEEE1394 device 250 Engine unit 301 First image input unit (table)
302 Second image input unit (back)
305 DRAM
321 Image input unit (DMAC)
322 Image memory 323 Memory control unit 324 Image transfer unit (DMAC)
325 Code transfer unit (DMAC)
326 Compression / decompression device 327 HDD controller 328 HD
400 Image Data Control IF Controller 402 DRAM Controller 3231 Input / Output Image Address Counter Unit 3232 Transfer Image Address Counter Unit 3233 Line Setting Unit 3234 Difference Calculation Unit 3235 Difference Comparison Unit 3236 Address Selector Unit 3237 Arbiter Unit 3238 Request Mask Unit 3239 Access Control Circuit

Claims (7)

Primary storage means having a first storage area for storing data on the front side of the document and a second storage area for storing the back side of the document ;
A double-sided reading means for performing double-sided reading for reading images on the front and back sides of a document in one scan;
A document size comparison unit that compares the maximum document size that can be stored in the primary storage unit by the duplex reading and the size of the read document;
After the double-sided reading is started, when the size of the read original is determined to be smaller than the maximum original size by the original size comparison means, the read data on the surface of the original is stored in the first storage area. At the same time, the back side data is stored in the second storage area, and when the double-sided reading is started, the original size is read when the size of the read original is determined to be larger than the maximum original size. Storage control means for storing the document data in a combined storage area that combines the first storage area and the second storage area;
After the two-sided reading is started, when it is determined that the size of the document read by the document size comparison unit is larger than the maximum document size, the amount of data stored in the combined storage area of the primary storage unit is determined. A stored data amount detecting means for detecting;
The double-sided reading is continued until the storage data amount stored in the combined storage area of the primary storage unit detected by the storage data amount detection unit reaches the maximum storage capacity of the primary storage unit, and the detection is performed. Control means for controlling the double-sided reading means so as to stop the double-sided reading operation when the amount of stored data reaches the maximum storage capacity;
An image reading apparatus comprising:   The image reading apparatus according to claim 1, wherein the control unit notifies the user when the detected storage data amount reaches the maximum storage capacity. The double-sided reading means can selectively execute the double-sided reading and single-sided reading of reading only one side of a document,
When the detected storage data amount reaches the maximum storage capacity, the control means stops the double-sided reading, changes to the single-sided reading operation, or is stored in the primary storage means. The image reading apparatus according to claim 2, wherein the user is notified that the mode for changing the document size according to the amount of image data being present can be selected.   The image reading apparatus according to claim 3, wherein the control unit controls the double-sided reading unit according to a mode selected by a user.   The control unit switches the operation of the double-sided reading unit to a preset setting operation when the detected storage data amount reaches the maximum storage capacity after the double-sided reading by the double-sided reading unit is started. The image reading apparatus according to claim 1.   6. The image reading apparatus according to claim 5, further comprising setting operation specifying means for receiving specification of the setting operation by a user.   An image forming apparatus comprising the image reading apparatus according to claim 1.

Images