JP2012138798A - Image reading device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost and labor hour for changing processing contents of image processing in order to develop an ability of pre-installed image processing executed by dedicated hardware.SOLUTION: An image reading device includes: an image reading section executing image reading processing for reading a manuscript; an image processing circuit constructed by dedicated hardware executing pre-installed image processing; a program storage section storing image processing program implemented with image processing different from the pre-installed image processing executed by the image processing circuit; an image processing section executing the image processing program stored in the program storage section; and an execution control section causing the image processing circuit to execute the pre-installed image processing on data read by the image reading processing executed by the image reading section and successively causing the image processing section to execute the image processing implemented in the image processing program on data on which the pre-installed image processing has already been executed.

Description

  The present invention relates to a technique for updating processing contents of image processing in an image reading apparatus.

  Conventionally, an electrical apparatus such as an image forming apparatus that processes image data of a document generated by an image reading device such as a scanner reading the document is used. For example, the scanner itself or a document read by the scanner is used. Copiers, facsimiles, and complex machines for processing image data are used.

  Here, the image data of the document does not necessarily indicate the original image itself that appeared on the document due to the reading characteristics of the image reading apparatus, and therefore, for example, gamma correction, MTF (Modulation Transfer Function) correction, and the like. Image processing is performed.

  These image processes are executed by an image processing circuit capable of high-speed processing configured by ASIC (Application Specific Integrated Circuits) equipped only with hardware that does not require software. Alternatively, for example, image processing by ASIC by executing an image processing program that is implemented by hardware that can execute software, such as a microcomputer that causes a CPU to execute a program stored in a ROM. It is executed by an image processing unit that executes image processing at a lower speed than the above.

  For example, in Patent Document 1 below, an image processing unit configured by a plurality of image processing programs and one processing unit to execute various image processing, an image processing content unit for adding or updating an image processing program, and an image A technique is disclosed that includes an operation determination unit that determines the presence or absence of a processing unit that enables an operation of an image processing program when a processing program is added or updated, and executes a plurality of image processing programs.

  In this technology, the processing speed is lower than when image processing is executed only by hardware, but the processing contents of image processing can be changed only by changing the image processing program. Compared with the case where image processing is executed, the processing contents of the image processing can be changed flexibly and inexpensively.

JP 2002-207606 A

  However, when the image processing is executed by hardware dedicated to image processing such as ASIC, the image processing speed is high, but for example, image formation with inexpensive image processing hardware having poor image processing capability is performed. In order to improve the image processing capability after purchasing a product, such as when a device is purchased, new hardware is provided to execute new image processing that has been changed to processing content that improves the image processing capability. It was necessary to replace the cost and the new hardware.

  Therefore, the present invention has been made in view of such circumstances, and is intended to change the processing content of the image processing in order to improve the capability of image processing incorporated in advance executed by dedicated hardware. An object of the present invention is to provide an image reading apparatus and an image forming apparatus capable of reducing cost and labor.

The invention according to claim 1 is an image reading unit that performs an image reading process for reading an original;
An image processing circuit configured with dedicated hardware for executing pre-installed image processing;
A program storage unit that stores an image processing program that implements image processing different from the previously incorporated image processing executed by the image processing circuit;
An image processing unit for executing the image processing program stored in the program storage unit;
After the image processing circuit executes the pre-installed image processing on the data read by the image reading process by the image reading unit, the pre-installed image processing is performed on the data. An execution control unit that causes the image processing unit to execute image processing implemented in the image processing program;
An image reading apparatus.

  In the present invention, in order to improve the capability of image processing incorporated in advance in the image processing circuit, in addition to the image processing incorporated in advance in the image processing circuit, the image processing unit stored in the program storage unit The image processing implemented in the program can be executed by the image processing unit. For this reason, it is possible to reduce the cost for newly providing dedicated hardware for executing pre-installed image processing performed in the image processing circuit and the trouble of replacing with the new dedicated hardware.

According to a second aspect of the present invention, there is provided the image reading device according to the first aspect, wherein all of the pre-installed image processing executed by the image processing circuit and the program storage unit are stored. Among the image processing implemented in all the image processing programs, the image processing apparatus further includes an execution order receiving unit that receives designation of an execution order of the image processing when the execution control unit executes the image processing.
The execution control unit sequentially executes the image processing according to the execution order received by the execution order reception unit.

  In the present invention, for example, an image processing program in which new image processing is implemented is stored in the program storage unit, and the new image processing is executed after execution of the first pre-installed image processing. Pre-built-in image processing performed in the image processing circuit can be executed by flexibly specifying the execution order of the new image processing, such as executing the second pre-built-in image processing after the processing is executed. The ability of can be improved flexibly.

According to a third aspect of the present invention, there is provided an image reading apparatus according to the first or second aspect;
A recording unit for forming an image made of image data after image processing by the image processing circuit or the image processing unit on a recording medium;
An image forming apparatus.

  According to the present invention, an image appropriately subjected to image processing by an image processing circuit or image processing can be formed on a recording medium.

  According to the present invention, in order to improve the capability of image processing incorporated in advance executed by dedicated hardware, an image reading apparatus capable of reducing the cost and labor for changing the processing content of the image processing, and An image forming apparatus can be provided.

1 is a schematic configuration diagram of a multifunction peripheral as an example of an image forming apparatus according to the present invention. FIG. 2 is a block diagram showing an electrical configuration of the multifunction machine. 6 is a flowchart illustrating an example of an operation for reading a document.

  Hereinafter, an image forming apparatus according to the present invention will be described with reference to the drawings. In the following embodiments, an example of an image forming apparatus according to the present invention will be described by taking as an example a form in which the image forming apparatus is integrated into a multifunction machine having functions such as a color copy, a scanner, a facsimile, and a printer.

  As shown in FIG. 1, the multifunction machine 1 includes an image reading device 20 and a device main body 30. The image reading apparatus 20 includes a document conveying unit 21 and an image reading unit 22.

  The document transport unit 21 realizes an ADF (Automatic Document Feeder), and includes a document table 241, a paper feed roller 232, a transport drum 233, a paper discharge roller 234, and a paper discharge tray 235. .

  The document table 241 is a place where the document is placed. The documents placed on the document table 241 are taken one by one by the paper feed roller 232 and conveyed to the conveyance drum 233. The document that has passed through the transport drum 233 is discharged to a discharge tray 235 by a discharge roller 234.

  The image reading unit 22 optically reads an image of a document to generate image data, and outputs the image data to an image processing circuit or an image processing unit described later. The image reading unit 22 is provided in the apparatus main body 30, and includes a contact glass 221, a light source 222, a first mirror 223, a second mirror 224, a third mirror 225, a first carriage 226, a second carriage 227, an imaging lens 228, A CCD (Charge Coupled Device) 229 is provided. The light source 222 and the first mirror 223 are supported by the first carriage 226, and the second mirror 224 and the third mirror 225 are supported by the second carriage 227.

  In the image reading unit 22, a white fluorescent lamp such as a white LED is used as the light source 222, and the first mirror 223, the second mirror 224, the third mirror 225, the first carriage 226, the second carriage 227, and the imaging lens are used. 228 guides the reflected light reflected from the original to the CCD 229 when light is emitted from the light source 222 toward the original.

  The CIS 231 is provided downstream of the image reading unit 22 in the document conveyance direction. The CIS 231 is provided at a position where the surface opposite to the document surface read by the image reading unit 22 can be read in the document conveyance path.

  As an original reading method of the image reading apparatus 20, a flat bed reading mode in which the image reading unit 22 reads an original placed on the contact glass 221 and an ADF reading mode in which the original is taken in by ADF and read in the middle of the conveyance. There is.

  In the flat bed reading mode, the light source 222 irradiates a document placed on the contact glass 221, and reflected light for one line in the main scanning direction is reflected in the order of the first mirror 223, the second mirror 224, and the third mirror 225. Then, the light enters the imaging lens 228. The light incident on the imaging lens 228 is imaged on the light receiving surface of the CCD 229.

  The CCD 229 is a one-dimensional image sensor. When the reflected light for one line in the main scanning direction of the document is received, the received reflected light is photoelectrically converted to obtain image data for one line in the main scanning direction of the document. Output.

  When the reading of one line of the document in the main scanning direction is thus completed, the first carriage 226 and the second carriage 227 are moved in a direction (sub-scanning direction, arrow Y direction) orthogonal to the main scanning direction. The line is read.

  In the ADF reading mode, the documents placed on the document table 241 are taken one by one by the paper feed roller 232, and the document passes over the reading position 230 provided in the conveyance path from the conveyance drum 233 to the paper discharge tray 235. In this case, the light source 222 irradiates the original, and the reflected light for one line in the main scanning direction is reflected by the first mirror 223, the second mirror 224, and the third mirror 225 in this order, and enters the imaging lens 228. The light incident on the imaging lens 228 is imaged on the light receiving surface of the CCD 229. Subsequently, the document is transported in the sub-scanning direction by the document transport unit 21 and the next line is read.

  As described above, the image reading unit 22 performs image reading processing for reading the original while moving in the sub-scanning direction relative to the original placed on the contact glass 221 in the flatbed reading mode or the ADF reading mode. Do. In the following description, those not particularly described will be described on the assumption that the original is read in the flatbed reading mode.

  The apparatus main body 30 has been transported from a plurality of paper feed cassettes 461, a paper feed roller 462 that feeds sheets (recording media) from the paper feed cassette 461 one by one to the recording unit 40, and a paper feed cassette 461. A recording unit 40 for forming an image on a sheet and a stack tray 60 disposed on the left side are provided.

  The apparatus main body 30 further includes a manual feed tray 471, a size of paper that is not stored in any paper feed cassette from the manual feed tray 471, or a paper that has already been subjected to image formation on one side (back paper). ), An arbitrary recording medium such as an OHP sheet can be placed, and is fed into the apparatus main body 30 one by one by a paper feed roller 472.

  The recording unit 40 is acquired by the neutralization device 421 that neutralizes residual charges from the surface of the photosensitive drum 43, the charging device 422 that charges the surface of the photosensitive drum 43 after neutralization, and the image reading unit 22, and is described later. An exposure apparatus that outputs a laser beam to expose the surface of the photosensitive drum 43 based on image data that has been subjected to image processing by a processing circuit or an image processing unit, and forms an electrostatic latent image on the surface of the photosensitive drum 43 423 and developing devices 44C and 44M that form toner images of cyan (C), magenta (M), yellow (Y), and black (K) on the photosensitive drum 43 based on the electrostatic latent image. , 44Y, 44K, a transfer drum 49 on which the toner images of the respective colors formed on the photosensitive drum 43 are transferred and superimposed, and a transfer device 4 that transfers the toner image on the transfer drum 49 to a sheet. When, and a fixing device 45 which heats the sheet on which the toner image is transferred to fix the toner image on the paper.

  Note that toner is supplied to cyan, magenta, yellow, and black colors from a toner supply container (toner cartridge) (not shown). Further, conveyance rollers 463 and 464 that convey the sheet that has passed through the recording unit 40 to the stack tray 60 or the discharge tray 48 are provided.

  An operation unit 50 is provided in front of the apparatus main body 30. The operation unit 50 includes a display unit 51 including an LCD (Liquid Crystal Display) and the like, and an operation key unit 52 for inputting an operation instruction from the operator.

  The operation key unit 52 includes a numeric keypad, a start key, a function switching key unit, and the like. The start key is a key for receiving an instruction to start each operation such as a copy operation and a scan operation from the operator. The numeric keypad is a key for receiving an instruction for designating the number of copies from the operator. The function switching key unit is a key for receiving from the operator a function switching instruction for switching between a scanner function, a facsimile function, a printer function, a copy function, and the like.

  The display unit 51 includes an LCD (Liquid Crystal Display) or the like, and includes a touch panel unit combined with a touch panel function. The display unit 51 displays various operation screens and allows an operator to input execution commands for various functions by touching a display surface (displayed operation keys).

  Next, an example of the electrical configuration of the multifunction machine 1 will be described. As shown in FIG. 2, the multifunction machine 1 includes the document transport unit 21, the image reading unit 22, the image processing circuit 23, the image processing unit 24, the recording unit 40, and the operation unit 50. The communication unit 70 and the control unit 10 are provided.

  The image processing circuit 23 and the image processing unit 24 perform gamma correction, color correction, chromatic aberration correction, MTF correction, or the like on image data (read data) generated by reading an original with the image reading unit 22. Image processing such as correction processing is performed. The image data subjected to the image processing by the image processing circuit 23 or the image processing unit 24 is used when the recording unit 40 forms an image.

  Since each image processing executed by the image processing circuit 23 or the image processing unit 24 is a known technique, the description will be simplified as follows.

  The gamma correction is a correction for converting the relationship between input and output values of RGB color components in the CCD 229 from nonlinear to linear. Color correction refers to correction in which pixel values of RGB colors are filtered using a color correction filter, and mixed color components included in pixel values of RGB colors are removed for each pixel.

  The chromatic aberration correction is correction for avoiding occurrence of color misregistration (chromatic aberration) in an image formed by the CCD 229 due to a difference in wavelength of RGB colors and characteristics of the imaging lens 228. For example, when the output data for R color is larger than the output data for G color, the output data for G color is amplified to obtain output data having the same size as the output data for R color, and the output data between RG colors Reduce the output data error.

  In the MTF correction, the pixel value of the area evaluated that “blurring” of the incident light to the CCD 229 by the imaging lens 228 is seen using the MTF value is filtered using the MTF correction filter, and the sharpened image data The correction to obtain is shown.

  The image processing circuit 23 is configured to be capable of high-speed processing with dedicated hardware such as ASIC (Application Specific Integrated Circuits), and executes image processing incorporated in the MFP 1 in advance. Note that the pre-installed image processing here is image processing in which the processing content cannot be changed because the image processing circuit 23 for executing the image processing is configured by dedicated hardware. Show.

  On the other hand, the image processing unit 24 includes a program storage unit 25 configured to store an image processing program composed of a flash memory or the like, and a RAM (Random Access Memory) (RAM) having a function of temporarily storing data and a function as a work area. (Not shown) and a CPU (not shown) that reads and executes an image processing program from the program storage unit 25, and the CPU, the RAM, and the program storage unit 25 exchange data via a data bus. Configured to do. The CPU executes an image processing program stored in the program storage unit 25, thereby executing image processing according to the content of the program.

  The image processing unit 24 is slower in processing speed than the image processing circuit 23, but edits the content of the image processing program and stores it in the program storage unit 25, thereby flexibly changing the processing content of the image processing. Can be modified.

  For example, as a specific example, the multifunction device 1 includes an image processing circuit 23 configured to perform gamma correction as image processing and an image processing circuit 23 configured to perform color correction as image processing. The program storage unit 25 stores an image processing program that implements execution of chromatic aberration correction and MTF correction. The image processing unit 24 executes each image processing program by executing the image processing program. It is assumed that the chromatic aberration correction or the MTF correction implemented in the program is performed.

  Each image processing circuit 23 and the image processing unit 24 temporarily store output data in a RAM of the control unit 10 to be described later, and input / output data to / from each other via the RAM using the data stored in the RAM as input data. Is configured to do.

  Returning to FIG. 2, the communication unit 70 communicates various data with a predetermined external device (not shown) such as a personal computer.

  The control unit 10 includes a RAM (Random Access Memory) having a function of temporarily storing data and a function as a work area, a flash memory that stores a program in advance, and a CPU that reads and executes the program from the flash memory The CPU, the RAM, and the flash memory are configured to exchange data via a data bus. The CPU appropriately executes a program stored in the flash memory, thereby executing a process according to the content of the program and controlling the operation of each unit.

  The control unit 10 functions as an execution order receiving unit 13, a reading instruction receiving unit 14, and an execution control unit 15.

  The execution order receiving unit 13 is incorporated in advance and executed by the image processing circuit 23 that is designated and operated on the operation screen displayed by the control unit 10 in accordance with a display instruction input by the operation of the operation unit 50 by the user. Of the image processing implemented in all image processing and all image processing programs stored in the program storage unit 25, the execution order of each image processing to be executed by the execution control unit 15 described later is accepted.

  Returning to FIG. 2, the reading instruction receiving unit 14 reads the document by the image reading unit 22 input on the operation screen displayed by the control unit 10 in accordance with the display instruction input by the operation of the operation unit 50 by the user. An instruction to execute the document reading process is received.

  When the reading instruction receiving unit 14 receives an instruction to execute a document reading process, the execution control unit 15 sends an instruction to read the document to the image reading unit 22, and the image is read according to the execution order received by the execution order receiving unit 13. The image processing executed in advance in the processing circuit 23 and the image processing implemented in the image processing program stored in the program storage unit 25 are sequentially executed.

  As described above, the image reading apparatus 20 as an example of the image reading apparatus according to the present invention includes the document conveying unit 21 and the image reading unit 22 as described above, and further includes the image processing circuit 23, the image processing unit 24, and the like. A program storage unit 25 and a control unit 10 are provided.

  Hereinafter, an operation for reading a document will be described. As shown in FIG. 3, the execution control unit 15 executes image processing incorporated in advance in the image processing circuit 23 and image processing implemented in the image processing program stored in the program storage unit 25. After the execution order is received by the execution order receiving unit 13 (S1), when the reading instruction receiving unit 14 receives a reading instruction of the original (S2; YES), the execution control unit 15 is for one line of the original. Is sent to the image reading unit 22 (S3).

  Then, execution control is performed until all image processing executed in the execution order received by the execution order receiving unit 13 is executed on the data obtained by reading one line of the original (S4; NO). The unit 15 inputs data for one line of the original read in step S3 in accordance with the execution order determined in step S1, and causes each image processing to be executed by the image processing circuit 23 or the image processing unit 24. The data after the image processing is executed is input again, and the image processing circuit 23 or the image processing unit 24 executes the image processing in the execution order subsequent to the image processing (S5 to S7).

  Here, when the execution control unit 15 executes the pre-installed image processing executed by the image processing circuit 23 (S5; YES), the data for one line of the original read in step S3 or the pre-installed data processing. The data after image processing executed in the execution order immediately before the image processing is input to the image processing circuit 23 that executes the pre-installed image processing, and the pre-installed image processing is executed (S6). ).

  On the other hand, when the image processing unit 24 executes image processing (S5; NO), the execution control unit 15 executes the data for one line of the original read in step S3 or the execution order immediately before the image processing. The image-processed data is input to the image processing unit 24, and an instruction to execute the image processing program in which the image processing is implemented is sent to the image processing unit 24 to execute the image processing (S7).

  For example, to explain according to the above specific example, the execution order receiving unit 13 performs gamma correction executed by the image processing circuit 23, color correction executed by the image processing circuit 23, chromatic aberration correction implemented in the image processing program, When the execution order for executing the image processing in the order of MTF corrections implemented in the image processing program is received, the execution control unit 15 first reads the data for one line of the original read in step S3 according to the execution order. Is input to the image processing circuit 23 that performs gamma correction to execute gamma correction (S5; YES, S6). Subsequently, the gamma-corrected data is input to the image processing circuit 23 that performs color correction. Then, color correction is executed (S6).

  Next, the execution control unit 15 inputs the color-corrected data to the image processing unit 24 and sends an instruction to execute an image processing program for correcting chromatic aberration to the image processing unit 24 to execute chromatic aberration correction. (S5; NO, S7), the data after chromatic aberration correction is input to the image processing unit 24, and an instruction to execute an image processing program for MTF correction is sent to the image processing unit 24 to execute MTF correction ( S5; NO, S7).

  Returning to FIG. 3, the execution control unit 15 continues until all image processing received by the execution order receiving unit 13 is executed on the read data for all the lines of the document (S8; NO). In S3, an instruction to read the next one line is sent to the image reading unit 22, and the processes after Step S4 are executed.

  As described above, in order to improve the capability of image processing incorporated in advance in the image processing circuit 23, in addition to the image processing incorporated in advance in the image processing circuit 23, it is stored in the program storage unit 25. Image processing implemented in the image processing program can be executed by the image processing unit 24. For this reason, it is possible to reduce the cost for newly installing dedicated hardware for executing image processing incorporated in advance in the image processing circuit 23 and the trouble of replacing it with the new dedicated hardware.

  Instead of the configuration of the specific example described above, for example, the image processing circuit 23 is configured by one dedicated hardware that executes two pre-installed image processes in the order of gamma correction and color correction. May be.

  In this case, data is directly input / output between the circuit for gamma correction and the circuit for color correction in the dedicated hardware, but not only an image processing program that implements new image processing, but also gamma correction and color The image processing program in which the correction is implemented is also stored in the program 25, and is implemented in the image processing program without specifying the execution order of the image processing circuit 23 executed in the two pre-installed image processes. By specifying the execution order to be executed by the execution control unit 15 in the order of gamma correction, new image processing, and color correction implemented in the image processing program, new image processing is performed between gamma correction and color correction. Can be executed.

  In this way, the execution order of new image processing can be specified flexibly, and the capability of image processing built in advance performed by the image processing circuit 23 can be flexibly improved.

  In the above-described embodiment, the multifunction apparatus is described as an example of the image forming apparatus according to the present invention. However, the image forming apparatus according to the present invention is not limited to this, and includes a printer, a copier, a scanner, Alternatively, an image forming apparatus such as a FAX may be used.

  The present invention is not limited to the configuration of the above-described embodiment, and various modifications can be made. The configurations and processes shown in FIG. 1 to FIG. 3 are merely examples of the embodiment according to the present invention, and the present invention is not limited to the above-described embodiment.

1 MFP (image forming device)
13 execution order receiving unit 14 reading instruction receiving unit 15 execution control unit 20 image reading device 22 image reading unit 23 image processing circuit 24 image processing unit 25 program storage unit 40 recording unit

Claims (3)

An image reading unit for performing an image reading process for reading an original;
An image processing circuit configured with dedicated hardware for executing pre-installed image processing;
A program storage unit that stores an image processing program that implements image processing different from the previously incorporated image processing executed by the image processing circuit;
An image processing unit for executing the image processing program stored in the program storage unit;
After the image processing circuit executes the pre-installed image processing on the data read by the image reading process by the image reading unit, the pre-installed image processing is performed on the data. An execution control unit that causes the image processing unit to execute image processing implemented in the image processing program;
An image reading apparatus comprising: Of the image processing implemented in the image processing circuit and the image processing implemented in all the image processing programs stored in the program storage unit, executed by the execution control unit An execution order receiving unit that receives designation of an execution order of each of the image processes when
The image reading apparatus according to claim 1, wherein the execution control unit sequentially executes the image processing according to the execution order received by the execution order reception unit. The image reading apparatus according to claim 1 or 2,
A recording unit for forming an image made of image data after image processing by the image processing circuit or the image processing unit on a recording medium;
An image forming apparatus.

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