JP2010056800A - Image processor, image forming apparatus, control method of image processor, control program, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress circuit scales of an image processing apparatus processing image data to be handled in a copying machine and a multifunction peripheral having a preview display function. <P>SOLUTION: The image processing apparatus 102 supplies image data of an image to be printed to an image output device 103 which performs printing in a copy mode. The image processing apparatus 102 supplies the image data to an image display device 104 so as to display a preview of the image on the image display device 104 before the printing is executed. The image processing apparatus 102 includes a color correction unit 13 which performs conversion from RGB to CMY on the image data supplied to the image output device 103 and conversion from RGB to R'G'B' on the image data supplied to the image display device 104. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image processing apparatus that processes image data of a preview (thumbnail) displayed on a display apparatus, an image forming apparatus, a control method for the image processing apparatus, a control program, and a recording medium.

  An image forming apparatus such as a copier or a multi-function printer converts image data indicating an image to be printed in accordance with a document type and setting conditions (print density, scaling ratio, single-sided or double-sided printing, margin size, etc.). Apply image processing. Further, some image forming apparatuses display a preview of an image to be printed on a display device based on the image data subjected to the image processing. Note that the preview display mode includes a mode in which images to be printed are displayed one page at a time, and a mode in which images to be printed consisting of a plurality of pages are collectively displayed.

  The following Patent Document 1 exists as a prior document relating to an image processing apparatus provided in a copying machine or a multifunction peripheral that performs preview display. Patent Document 1 discloses a technique for generating a preview image without performing edge enhancement processing on image data. An image processing apparatus disclosed in Patent Document 1 includes a logarithmic conversion circuit that converts an RGB signal read by a scanner into a CMY density signal, and a masking / UCR that generates a CMYK density signal suitable for printer characteristics based on the CMY density signal. A circuit, an image editing circuit that performs trimming, painting, scaling, and the like, a spatial filter circuit that performs smoothing processing when a scanned original is a printed photo original, and a spatial filter circuit that performs edge enhancement after smoothing processing And a hard copy is output based on the CMYK density signal after the edge enhancement processing.

  In addition, the image processing apparatus performs reverse conversion (inverse conversion with respect to masking / UCR circuit conversion) on the CMYK density signal after the smoothing process, and generates a CMY density signal; Inverse logarithmic conversion circuit that converts CMY density signals obtained by inverse conversion back to RGB signals, and a 3 × 3 matrix that converts RGB signals suitable for the scanner color space into RGB signals suitable for the color space of the display device A conversion circuit and a gamma correction circuit for correcting non-linearity of the display device are provided, and an image (preview) is displayed on the display device based on the RGB signals after the processing by the gamma correction circuit is performed.

Of the circuits described above, the logarithmic conversion circuit, the masking / UCR circuit, the image editing circuit, and the smoothing spatial filter circuit are shared by the hard copy process and the preview process. Of the circuits described above, the inverse masking circuit, the 3 × 3 matrix conversion circuit, and the gamma correction circuit are circuits that are used only when previewing is performed.
JP-A-9-135316 (Publication date: May 20, 1997)

  That is, an image processing apparatus provided in a copier / multifunction machine that performs preview display has an additional image processing circuit dedicated to preview processing in addition to the image processing circuit for print processing. Therefore, an image processing apparatus provided in a copier / multifunction peripheral having a preview display function has a larger circuit scale than an image processing apparatus provided in a copier / multifunction peripheral not having a preview processing function. It will have the problem of end.

  The present invention has been made to solve the above-described problem, and an object thereof is to suppress the circuit scale of an image processing apparatus that processes image data handled by a copier / multifunction peripheral having a preview display function. To do.

  In order to achieve the above object, according to the present invention, image data of an image handled in the above job is stored in a job device that executes any one of an image print job, an image transmission job, and an image filing job. Suppose that the image processing apparatus supplies the image data to the display device to display the image preview on the display device before executing the job, and executes the image data supplied to the job device. The first image processing to be performed and the second image processing to be executed on the image data supplied to the display device and different from the first image processing are executed using a circuit area common to both image processing. And a first image processing unit.

  According to the present invention, the first image processing and the second image processing can be performed in the same circuit area, not in different circuit areas. Therefore, according to the present invention, not only image processing for jobs (printing and the like), but also a configuration for performing image processing for preview before a job, it is possible to suppress the circuit scale of the image processing circuit. Play.

  In addition to the above configuration, the image processing apparatus of the present invention supplies image data of an image handled in the image print job to a printing apparatus that is a job apparatus that executes the image print job. The image print job is a copy process for printing an image based on image data read by a scanner. The first image process is for additive color mixing that is read by the scanner and is in accordance with the characteristics of the scanner. The image data is converted into image data for subtractive color mixing according to the characteristics of the printing apparatus, and the second image processing is performed by adding image data for additive color mixing according to the characteristics of the scanner to the display apparatus. It is preferable that the image data be converted into image data for additive color mixing according to the characteristics of the color. According to this configuration, during preview display, the image data for additive color mixing corresponding to the characteristics of the scanner is directly converted into image data for additive color mixing corresponding to the characteristics of the display device. For this reason, image data for copying can be converted into image data for preview display by one nonlinear conversion, conversion error accumulation can be suppressed, and deterioration of color reproducibility can be suppressed. On the other hand, in Patent Document 1, during preview, RGB data is temporarily converted into CMY data, CMY data is further converted into CMYK data, and then CMYK data is converted into CMY data and then converted into RGB data. Therefore, a total of four non-linear conversions are performed, so that a large amount of conversion errors accumulate and color reproducibility deteriorates.

  Further, in the image processing apparatus of the present invention, the first image processing is conversion processing for converting RGB image data into CMY image data, and the second image data input from the first image processing unit is input. An image processing unit is provided, and the second image processing unit converts the CMY image data after the first image processing into CMYK image data and outputs the converted CMYK image data. It is preferable to output the image data after having been subjected to processing without being processed. As a result, image data for a print job that needs to be converted from CMY to CMYK (black generation / under color removal processing), and preview image data that does not need to be subjected to black generation / under color removal processing. With respect to the above, there is an effect that the path of the image data in the image processing circuit can be made common and the configuration of the image processing circuit can be simplified.

  The image processing apparatus according to the present invention also provides image data necessary for a job to any of a job apparatus that executes an image print job, a job apparatus that executes an image transmission job, and a job apparatus that executes an image filing job. It may be possible to supply. Furthermore, the present invention may be an image forming apparatus that includes the image processing apparatus and the job apparatus, and the job apparatus is a printing apparatus.

  In addition, the present invention supplies image data of an image handled in the job to a job apparatus that executes any one of an image print job, an image transmission job, and an image filing job, and executes the job. In the control method of the image processing apparatus for supplying the image data to the display device in order to display the preview of the image on the display device before, a first executed on the image data supplied to the job device. Image processing and second image processing that is executed on the image data supplied to the display device and that is different from the first image processing are executed using a circuit area common to both image processing. And

  The first image processing unit included in the image processing apparatus of the present invention may be realized by a computer. In this case, a control program for operating the computer as the first image processing unit, the control program A recorded computer-readable recording medium also falls within the scope of the present invention.

  As described above, the image processing apparatus of the present invention is executed for the first image processing performed on the image data supplied to the job apparatus, the image data supplied to the display apparatus, and the above-described image data. The image processing apparatus includes a first image processing unit that executes second image processing different from the first image processing using a circuit area common to both image processing. Therefore, according to the present invention, there is an effect that the circuit scale of the image processing circuit can be suppressed.

  An embodiment of the image forming apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a schematic configuration of an image forming apparatus 100 according to the present embodiment.

  The image forming apparatus 100 according to the present embodiment is a digital color composite that executes a selected mode when any one of a copier mode, a print mode, a facsimile transmission mode, a facsimile reception mode, and an image transmission mode is selected. Machine.

  The copier mode (copying mode) means a mode for reading image data (reading a document to generate image data) and printing an image of the image data on paper. The print mode means a mode in which an image of image data sent from a terminal device connected to the image forming apparatus 100 is printed on paper. The facsimile transmission mode means a normal facsimile mode in which image data obtained by reading a document is transmitted to an external device through a telephone line, and an Internet facsimile mode in which the image data is attached to a mail and transmitted over the Internet. The facsimile reception mode means a mode in which image data is received from an external device by facsimile and an image of the received image data is printed on paper. The image transmission mode is (1) a mode in which image data generated by scanning a document is attached to an e-mail and transmitted to a specified address (scan to e-mail mode), and (2) generated by scanning a document. A mode in which image data is transmitted to a folder designated by the user (scan to ftp mode), and (3) a mode in which image data generated by reading a document is transmitted to a USB memory or the like attached to the image forming apparatus 100 (scan to usb mode). In the present embodiment, the facsimile transmission mode and the image transmission mode are classified as described above from the viewpoint of the image processing operation.

  When the copier mode / print mode is selected, the user outputs a monochrome image that outputs a monochrome image, a full color mode that outputs a full color image, or a single color image composed of only one color desired by the user. Either a single color mode or a two-color mode for outputting a two-color image composed of one color desired by the user and black can be selected.

  For example, in the copier mode or the print mode, when the user selects the single color mode, the single color image is printed. When the user selects the two-color mode in the copier mode or the print mode, the image data of the two-color image is printed. In the single color mode or the two-color mode, the user can select a desired color from R (red), G (green), B (blue), C (cyan), M (magenta), and Y (yellow). One color will be selected.

  In this embodiment, the automatic discrimination mode can be set in the copier mode. When this automatic determination mode is set, the image forming apparatus 100 performs automatic color determination processing (ACS) for determining whether a copy target is a color document or a black and white document. The output processing is performed in the full color mode, and when it is determined that the document is a black and white document, the output processing is performed in the black and white mode.

  As illustrated in FIG. 1, the image forming apparatus 100 includes an image input device 101, an image processing device 102, an image output device 103, an image display device 104, a reception device 105, a transmission device 106, a storage device 107, and a control unit 108. Have.

  The image input apparatus 101 is an image reading unit that reads a document and generates image data in the copier mode, the facsimile transmission mode, and the image transmission mode. More specifically, the image input device 101 includes a scanner unit including a CCD (Charge Coupled Device), and an electrical signal (analog image signal) obtained by color-separating light reflected from an original into RGB. And the electric signal is input to the image processing apparatus 102.

  Note that the image input apparatus 101 reads a document image in full color even when any of the above-described full color mode, single color mode, and two-color mode is selected. Further, the image input apparatus 101 reads a document image in full color even when the above-described automatic color discrimination process is performed in the image processing apparatus 102.

  The image processing apparatus 102 is an integrated circuit that performs image processing on image data (image signal), and includes an ASIC (Application Specific Integrated Circuit). As shown in FIG. 1, the image processing apparatus 102 includes an A / D (analog / digital) conversion unit 2, a shading correction unit 3, an input processing unit 4, a document type automatic discrimination unit 5, a region separation processing unit 6, a compression unit. Unit 7, region separation signal compression unit 8, decoding unit 9, region separation signal decoding unit 10, image quality adjustment unit 11, colorization processing unit 12, color correction unit 13, black generation / under color removal unit 14, spatial filter unit 15, a scaling unit 16, an output tone correction unit 17, and a halftone generation unit 18. The processing content of each block included in the image processing apparatus 102 will be described in detail later.

  The image processing apparatus 102 performs image processing on the image data transmitted from the image input apparatus 101 in the copier mode, facsimile transmission mode, and image transmission mode, and the image data transmitted from the terminal apparatus in the print mode. In the facsimile reception mode, image processing is performed on image data received from an external device. The image processing apparatus 102 transmits image data subjected to image processing to the image output apparatus 103 in the copier mode, print mode, and facsimile reception mode, and transmits image data subjected to image processing in the facsimile transmission mode to the transmission apparatus. 106 is transmitted. Further, the image processing apparatus 102 transmits image data subjected to image processing to a mail processing unit (not shown) in the scan to e-mail mode of the image transmission mode, and performs image processing in the scan to ftp mode. The image data is transmitted to a predetermined folder, and the image data subjected to image processing is transmitted to a predetermined USB memory in the scan to usb mode.

  An image output device (printer) 103 prints (forms) an image of image data sent from the image processing device 102 on a recording medium (for example, paper). For example, an electrophotographic method or an inkjet method is used. The color printer used can be mentioned. Note that “printing” in the present embodiment means any one of printing in the print mode, printing in the copier mode, and printing in the facsimile reception mode.

  The image display device 104 is a liquid crystal display provided in an operation panel (not shown) of the image forming apparatus 100, and is a display unit capable of displaying a color image. The image display device 104 is covered with a touch panel, and has a function as an input interface of the image forming apparatus 100. That is, the image display device 104 displays a GUI (graphical user interface) and an operation guide for inputting various commands to the image forming apparatus 100.

  In the image forming apparatus 100 according to the present embodiment, a preview of an image to be printed can be displayed on the image display device 104 before printing in the copier mode or the facsimile reception mode. Furthermore, in the image forming apparatus 100 of the present embodiment, a preview of an image to be transmitted can be displayed on the image display device 104 before execution of transmission in the facsimile transmission mode or the image transmission mode.

  When the full color mode is selected in the copier mode or the image transmission mode, a full color image preview is displayed. When the single color mode is selected, a single color image preview is displayed, and the two color mode is selected. When selected, a preview of a two-color image is displayed.

  The image display device 104 is not limited to a liquid crystal display, and may be a display means other than the liquid crystal display (for example, an organic EL display, a plasma display, etc.).

  The receiving device 105 is connected to a telephone line or the Internet and receives image data from an external device by facsimile communication. The transmission device 106 is connected to a telephone line or the Internet, and is a device that transmits image data input by the image input device 101 to an external device by facsimile communication.

  The storage device 107 is a hard disk for temporarily storing image data handled by the image processing device 102.

  The control unit 108 is a computer including a processor such as a CPU (Central Processing Unit) or a DSP (Digital Signal Processor), and comprehensively controls various hardware included in the image forming apparatus 100. In addition, the control unit 108 also has a function of controlling data transfer between each piece of hardware provided in the image forming apparatus 100.

  Next, details of processing executed in each block of the image processing apparatus 102 in each of the copier mode, the facsimile transmission mode, the facsimile reception mode, and the image transmission mode will be described in detail. In the image processing apparatus 102 according to the present embodiment, there is a block that operates when a certain mode a is selected but does not operate when a mode b different from the mode a is selected. (Mode a and mode b are any one of a copier mode, a facsimile transmission mode, a facsimile reception mode, and an image transmission mode). The image processing apparatus 102 also includes a block for changing the processing content according to the selected mode. Further, even if the selected mode is the same, the image processing apparatus 102 operates when processing image data for printing (for transmission) but does not operate when processing image data for preview. There are blocks that change processing contents between processing of image data for printing (for transmission) and processing of image data for preview. Therefore, in the following, the contents of processing executed in each block included in the image processing apparatus 102 will be described for each mode, and will be described separately for printing processing (or transmission processing) and preview display.

(1) Copier mode (1-1) During printing process (during image print job)
In the following, the image processing apparatus 102 will be described with reference to FIG. 1. FIG. 1 shows the flow of image data in the image processing apparatus 102 when printing processing is performed in the copier mode and the full color mode. Let me mention.

  The A / D (analog / digital) converter 2 is a block that converts a color image signal (RGB analog signal) sent from the image input apparatus 101 into digital image data (RGB digital signal). The shading correction unit 3 is a block that performs processing for removing various distortions generated in the illumination system, the imaging system, and the imaging system of the image input device 101 on the image data sent from the A / D conversion unit 2. . The input processing unit 4 is a block that performs gradation conversion processing such as γ correction processing on each of the RGB image data sent from the shading correction unit 3.

  The document type automatic discrimination unit 5 determines the type of the document read by the image input device 101 based on the RGB image data (RGB density signal) that has been subjected to processing such as γ correction by the input processing unit 4. Do. Here, as the type of document to be determined, there are a character document, a printed photograph document, a character printed photograph document in which characters and a printed photograph are mixed, and the like. Further, the document type automatic determination unit 5 performs an automatic color determination process (ACS: Auto Color Selection), which is a process for determining whether a read document is a color document or a monochrome document based on the image data. It is also possible to determine whether or not the document is a blank document (whether or not it is a plain document). The RGB image data output from the document type automatic determination unit 5 is input to the region separation processing unit 6 and the compression unit 7.

  Based on the RGB image data sent from the document type automatic discrimination unit 5, the region separation processing unit 6 discriminates for which pixel region the pixel is classified for each pixel of the input image. A process for generating a region separation signal indicating the discrimination result is performed. Here, the image regions discriminated by the region separation processing unit 6 include a black character region, a color character region, a halftone dot region, and the like. Note that the region separation processing may be in a form in which the image region is determined for each block including a plurality of pixels, instead of determining the image region for each pixel.

  The compression unit 7 is a block that performs processing for encoding the image data (RGB signals) sent from the document type automatic discrimination unit 5. Note that the encoding is performed based on, for example, a JPEG (Joint Photographic Experts Group) system.

  The region separation signal compression unit 8 is a block that performs compression processing on the region separation signal generated for each pixel. Note that the compression processing in the region separation signal compression unit 8 is performed based on, for example, the MMR (Modified Modified Reed) method and the MR (Modified Reed) method, which are lossless compression methods.

  The control unit 108 temporarily stores the encoded code (encoded image data) output from the compression unit 7 and the region separation signal code (compressed region separation signal) output from the region separation signal compression unit 8. It is stored in the device 107 and managed as filing data. Then, when the copy output operation is instructed, the control unit 108 reads out the encoded code and the region separation signal code corresponding to the encoded code from the storage device 107, and performs the decoding unit 9 and the region separation signal decoding unit 10. To each.

  The control unit 108 associates the storage address or data name of the encoded code with the storage address of the region separation signal code and enters them in the management table. That is, the control unit 108 controls reading or writing of the encoded code and the region separation signal code using the management table.

  The decoding unit 9 expands the encoded code into RGB image data by performing a decoding process on the encoded code. The region separation signal decoding unit 10 performs a decoding process on the region separation signal code. The decoded region separation signal is delivered to the black generation / undercolor removal unit 14, the spatial filter unit 15, and the halftone generation unit 18. In the black generation / undercolor removal unit 14, the spatial filter unit 15, and the halftone generation unit 18, the image processing content is switched according to the type of the image area.

  The image quality adjustment unit 11 detects the background of the RGB image data sent from the decoding unit 9 and performs background removal correction. Furthermore, the image quality adjustment unit 11 adjusts the RGB balance (color adjustment, overall color adjustment such as reddish blue), brightness, and vividness based on setting information input from the operation panel (not shown) by the user. Do.

  Further, when the single color mode is selected, the image quality adjustment unit 11 performs processing to convert RGB image data into CMY image data that is a complementary color of RGB. Here, the conversion process from RGB image data to CMY image data in the single color mode is executed by using the following Equation 1. Note that the coefficients r1 to r3 in Equation 1 are determined based on [Table 1]. For example, when the user selects cyan as the desired color in the single color mode, the values of r1 to r3 belonging to the column “Cyan” in [Table 1] are referred to, and r1 = 1, r2 = 0, r3 = 0 is selected.

  In other words, the output from the image quality adjustment unit 11 in the full color mode is RGB image data as shown in FIG. 1, and the output from the image quality adjustment unit 11 when the single color mode is selected is as follows. As shown in FIG. 2A, the image data is CMY. Note that the output from the image quality adjustment unit 11 when the two-color mode is selected is RGB image data as shown in FIG. FIG. 2A shows a part of the blocks of the image processing apparatus 102 when the printing process is performed in the copier mode and the single color mode, and FIG. 2 shows a part of blocks of the image processing apparatus 102 when a printing process is performed in the two-color mode.

  Further, the vividness adjustment executed by the image quality adjustment unit 11 can be realized by changing each value of r1 to r3 and a1 to a3 of the matrix of Expression 1 and using the matrix. Therefore, the matrix can be shared and the image processing circuit can be shared for the above vividness adjustment and the image data conversion process (conversion from RGB to CMY) in the single color mode. Therefore, in the present embodiment, the vividness adjustment and the image data conversion process in the single color mode are performed by the same processing unit (image quality adjustment unit 11).

  When the two-color mode is selected, the two-color processing unit 12 converts the RGB image data output from the image quality adjustment unit 11 into CMY image data as illustrated in FIG. It is a block that performs. The conversion process from RGB image data to CMY image data in the two-color mode is performed by, for example, the method of [Example 1] or [Example 2] described in Japanese Patent Application Laid-Open No. 2007-28336. Can be realized.

  In addition, when the full color mode is selected, the two-color processing unit 12 does not perform any processing on the RGB image data output from the image quality adjustment unit 11 as illustrated in FIG. The image data is transferred to the color correction unit 13 as it is (through). Further, when the single color mode is selected, the two-color processing unit 12 performs no processing on the CMY image data output from the image quality adjustment unit 11 as illustrated in FIG. First, the image data is transferred to the color correction unit 13 as it is (through).

  When the full color mode is selected, the color correction unit 13 performs color correction processing for converting the RGB image data output from the two-color processing unit 12 into CMY image data, and applies to the image data. This block performs processing for improving color reproducibility. The color correction process described above is realized by creating an LUT (lookup table) in which input values (RGB) and output values (CMY) are associated with each other, and looking up the output values from the created LUT. .

  Further, when the single color mode or the two-color mode is selected, the color correction unit 13 displays the CMY image output from the two-color processing unit 12 as illustrated in FIGS. No processing is performed on the data, and the image data is transferred to the black generation / undercolor removal unit 14 as it is (through).

  The black generation / under color removal unit 14 generates black (K) from the CMY image data output from the color correction unit 13 when the full color mode or the two-color mode is selected. On the other hand, it is a block for performing processing for generating new CMY image data by subtracting black (K) image data from original CMY image data. As a result, when the full color mode or the two-color mode is selected, the CMY image data is converted into the CMYK four-color data by the black generation / under color removal unit 14 as shown in FIGS. 1 and 2B. Converted to image data.

  Further, when the single color mode is selected, the black generation / under color removal unit 14 does nothing with respect to the CMY image data output from the color correction unit 13 as shown in FIG. Without performing the processing, the image data is transferred to the subsequent spatial filter unit 15 as it is (through).

  When the full color mode or the two-color mode is selected, the output of the black generation / under color removal unit 14 and the input / output of each block subsequent to the black generation / under color removal unit 14 are as shown in FIG. Thus, the image data is CMYK. However, when the single color mode is selected, the output of the black generation / under color removal unit 14 and the input / output of each block subsequent to the black generation / under color removal unit 14 are different from those in FIG. It becomes CMY image data.

  The spatial filter unit 15 applies spatial filter processing (enhancement processing, smoothing) to the CMYK or CMY image data output from the black generation / undercolor removal unit 14 based on a region separation signal (region identification signal). Etc.). That is, the spatial filter unit 15 executes different image processing for each image region based on the region separation signal.

  The scaling unit 16 is a block that performs image enlargement or reduction processing based on a scaling command (information indicating the magnification of a print image) input by a user via an operation panel (not shown).

  The output tone correction unit 17 is a block that performs output γ correction processing for outputting the image data output from the scaling unit 16 to a recording medium such as paper. The halftone generation unit 18 performs tone reproduction processing (halftone generation processing) necessary for printing an image in the image output apparatus 103 using an error diffusion method or a dither method.

  The CMYK or CMY image data output from the halftone generation unit 18 is transferred to the image output device 103, and the image output device 103 prints an image of the image data on a recording medium (for example, paper).

(1-2) Preview Display Next, the contents of processing executed in each block of the image processing apparatus 102 when displaying a preview of an image to be printed in the copier mode will be described with reference to FIG. FIG. 3 is a block diagram showing the same image forming apparatus 100 as the image forming apparatus 100 of FIG. 1, and shows the flow of image data when preview display is performed in the copier mode and the full color mode.

  An A / D (analog / digital) conversion unit 2, a shading correction unit 3, an input processing unit 4, a document type automatic discrimination unit 5, a region separation processing unit 6, a compression unit 7, a region separation signal compression unit 8, and a decoding unit. 9. Since the processes of the image quality adjustment unit 11 and the colorization processing unit 12 are the same as in the printing process, the description thereof is omitted below.

  As illustrated in FIG. 3, the region separation signal decoding unit 10 delivers the decoded region separation signal to the spatial filter unit 15 and the output tone correction unit 17 during preview display.

  The color correction unit 13 inputs RGB image data in the full color mode. Note that RGB image data is data that conforms to the color space of the scanner (image input device 101). Then, the color correction unit 13 performs a process of converting the RGB image data into R′G′B ′ image data suitable for the color space of the image display device 104.

  That is, the color correction unit 13 performs processing for converting RGB image data suitable for the image reading characteristics of the scanner into R′G′B ′ image data suitable for the display characteristics of the display device. Note that the process of converting RGB image data to R′G′B ′ image data was also created by creating an LUT in which input values (RGB) and output values (R′G′B ′) were associated with each other. This is accomplished by looking up the output value from the LUT.

  In the present embodiment, in the full color mode, conversion processing from RGB image data during printing to CMYK image data and conversion from RGB image data during preview display to R′G′B ′ image data are performed. The image processing circuit is shared with the conversion process.

  Here, FIG. 3 shows the image forming apparatus 100 when the full color mode is selected, as in FIG. 1, and the color correction unit 13 inputs RGB image data in the full color mode. It has become. However, in the single-color mode or the two-color mode, as shown in FIGS. 4A and 4B, the color correction unit 13 inputs CMY image data. 4A shows a part of the block of the image processing apparatus 102 when the preview display process is performed in the copier mode and the single color mode, and FIG. 4B shows the copier mode. In addition, a part of the blocks of the image processing apparatus 102 when the preview display process is performed in the two-color mode is shown.

  In the single color mode or the two-color mode, the color correction unit 13 performs a process of converting CMY image data into R′G′B ′ image data. That is, the color correction unit 13 performs processing for converting CMY image data suitable for the printing characteristics of the printing process into R′G′B ′ image data suitable for the display characteristics of the display device. The process of converting CMY image data into R'G'B 'image data is also created by creating an LUT that associates input values (CMY) with output values (R'G'B'). This is accomplished by looking up the output value from the LUT.

  As shown in FIGS. 3 and 4, the black generation / under color removal unit 14 outputs R ′ output from the color correction unit 13 in any of the single color mode, the two color mode, and the full color mode. No processing is performed on the G′B ′ image data, and the image data is transferred (through) to the subsequent spatial filter unit 15 as it is.

  The spatial filter unit 15 performs spatial filter processing (enhancement processing, smoothing processing) on the R′G′B ′ image data output from the black generation / undercolor removal unit 14 using a digital filter based on the region separation signal. Etc.). That is, in the spatial filter unit 15, different image processing is performed for each image region based on the region separation signal as in the print processing.

  The scaling unit 16 performs a thinning process (a process for reducing the number of pixels) that converts the number of pixels of the image composed of R′G′B ′ image data output from the spatial filter unit 15 into the number of pixels of the image display device 104. I do. The image display device 104 provided in the operation panel of the image forming apparatus 100 has a lower resolution than the resolution of image data to be printed, and is usually an extremely small display. Therefore, it is necessary to thin out the image data during preview display. The magnification unit 16 enlarges an image based on a magnification command (information indicating display magnification, for example, a fixed magnification such as 2 to 4) input from an operation panel (not shown) provided in the image forming apparatus. And reduction processing is performed.

  The output tone correction unit 17 performs an output γ correction process on the image data output from the scaling unit 16 based on the region separation signal. More specifically, the output tone correction unit 17 selects a different gamma curve depending on the image region based on the region separation signal, and varies the content of the output γ correction processing for each image region. For example, a gamma curve corresponding to the display characteristics of the image display device 104 is selected for a region other than a character, and a gamma curve for displaying a character clearly is selected for a character region. Here, FIG. 5A is a gamma curve corresponding to the display characteristics of the image display device 104. Further, the curve indicated by the solid line in FIG. 5B is a gamma curve for clearly displaying characters. The broken line in FIG. 5B is a gamma curve according to the display characteristics of the image display device 104, and is shown for comparison with a gamma curve for clearly displaying characters.

  In the present embodiment, the output tone correction unit 17 selects the gamma curve based on the region separation signal, but only the gamma curve of FIG. 5A is selected without performing selection based on the region separation signal. It may be used to perform output gradation correction.

  Then, the halftone generation unit 18 does not perform any processing on the R′G′B ′ image data output from the output tone correction unit 17, and uses the image data as it is to the subsequent image display device 104. Deliver (through). Thereby, the image display device 104 can display a preview of the image to be copied based on the image data of R′G′B ′.

  Note that the output γ correction processing executed in the output tone correction unit 17 may be executed in the image quality adjustment unit 11.

  Further, when the full color mode is selected during the copier mode preview display, or when the automatic discrimination mode is selected and the color document is determined during the copier mode preview display, the output process (print process / display process) ) Is displayed on the image display device 104, for example, identification information (for example, “full color” characters) for recognizing that the user is to perform in full color. On the other hand, the image forming apparatus 100 performs an output process when the monochrome mode is selected during the copier mode preview display, or when the automatic discrimination mode is selected and the monochrome document is determined during the copier mode preview display. Is displayed on the image display device 104 as identification information (for example, characters indicating “black and white”) for recognizing that the user is to be performed in the monochrome mode.

  Thereby, it is possible to notify the user in an easy-to-understand manner in which mode the image data of the document to be copied is processed, and the user can appropriately select the subsequent processing. For example, when the automatic determination mode is selected, if there is a portion written in red in a part of a document written in black characters, the document type automatic determination unit 5 determines that the document is a color document. If it is not desired to output in the automatic determination mode, it is possible to change from the automatic discrimination mode to the monochrome mode for output.

  Further, identification information (characters of “full color” or “monochrome”) for allowing the user to recognize that the output process is performed in full color or monochrome is previewed as indicated by reference numeral 160 in FIG. The preview image is displayed so as not to overlap the image. Further, the identification information 160 may be displayed when a predetermined button (for example, the key 150 in FIG. 12A) is pressed while the preview image is displayed.

  For example, a method described in Japanese Patent Application Laid-Open No. 4-282968 can be used as a method of automatic color determination processing performed by the document type automatic determination unit 5. This method determines whether each pixel is a color pixel or a monochrome pixel (monochrome pixel), and detects the presence of a continuous color pixel group in a predetermined order and a predetermined number or more. A pixel group is recognized as a color block, and if a predetermined number or more of color blocks exist in one line, that line is recognized as a color line. If a predetermined number of color lines are present in the document image, the document image is determined as a color image. Otherwise, it is determined as a monochrome image (monochrome image).

(1-3) Operation / non-operation of each block As described above, the two-color processing unit 12 of the image quality adjustment unit 11 to the halftone generation unit 18 does not operate during printing in the full color mode. All other blocks operate (see FIG. 1). On the other hand, of the image quality adjustment unit 11 to the halftone generation unit 18, the two-color processing unit 12, the black generation / undercolor removal unit 14, and the halftone generation unit 18 do not operate during full color mode preview display. However, all other blocks operate (see FIG. 3).

  Further, during printing in the two-color mode, the color correction unit 13 of the image quality adjustment unit 11 to the halftone generation unit 18 does not operate, but all other blocks operate (FIG. 2B). reference). On the other hand, of the image quality adjustment unit 11 to halftone generation unit 18, the black generation / undercolor removal unit 14 and the halftone generation unit 18 do not operate during the two-color mode preview display. All the blocks operate (see FIG. 4B).

  Further, during the printing in the single color mode, among the image quality adjustment unit 11 to the halftone generation unit 18, the two-color processing unit 12, the color correction unit 13, and the black generation / undercolor removal unit 14 do not operate. All other blocks operate (see FIG. 2A). On the other hand, during the preview display in the single color mode, among the image quality adjustment unit 11 to halftone generation unit 18, the two-color processing unit 12, the black generation / undercolor removal unit 14, and the halftone generation unit 18 operate. However, all other blocks operate (see FIG. 4A).

(1-4) Processing Procedure Next, an example of the processing procedure when the copier mode and the full color mode are selected will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of a processing procedure of the image forming apparatus when the copier mode and the full color mode are selected.

  When copier mode is selected and the start key is pressed (YES in S1), image forming apparatus 100 scans the document (S2) to generate RGB analog signals. Note that before pressing the start key of S1, the user inputs setting information indicating whether or not preview display is necessary, thereby setting the presence or absence of preview display for the image forming apparatus 100.

  After S2, the image forming apparatus 100 converts RGB analog signals into RGB image data (digital data) (S3), performs shading correction on the image data (S4), and performs RGB after shading correction. Input γ correction processing is performed on the image data (S5). After S5, the image forming apparatus 100 performs document type determination processing and region separation processing based on the RGB image data (S6), and further stores the RGB image data in the storage device 107 (S7).

  After S7, the image forming apparatus 100 determines whether “Preview display is present” is set (S8). If “Preview display is present” is not set, Steps S9 to S16 are executed. When “display present” is set, S17 to S23 are executed. Hereinafter, S9 to S16 will be described first, and then S17 to S23 will be described.

  If “Preview Display Available” is not set (NO in S8), the image forming apparatus 100 reads RGB image data from the storage device 107 and performs image quality adjustment processing such as background removal correction and vividness adjustment ( S9). Thereafter, the image forming apparatus 100 converts RGB image data corresponding to the characteristics of the scanner into CMY image data corresponding to the characteristics of the printer (S10), and further converts the CMY image data into CMYK image data. (S11). Thereafter, the image forming apparatus 100 performs a spatial filter process on the CMYK image data based on the result of the region separation process (S12), and performs a scaling process on the CMYK image data after the spatial filter process (S12). S13). After S13, the image forming apparatus 100 performs output γ correction processing and gradation reproduction processing on the CMYK image data (S14, S15), prints the image of the image data on paper (S16), and performs the processing. finish.

  If it is determined in S8 that “Preview display is present” is set (YES in S8), the image forming apparatus 100 reads out RGB image data from the storage device 107, and the same image quality adjustment process as the image quality adjustment process in S9. (S17). Thereafter, the image forming apparatus 100 converts RGB image data corresponding to the characteristics of the scanner into R′G′B ′ image data corresponding to the characteristics of the display device (S18). After S18, the image forming apparatus 100 performs a spatial filter process on the R′G′B ′ image data based on the result of the region separation process (S19), and the R′G′B ′ image data is displayed. The thinning process is performed on the image data of the R′G′B ′ so as to match the resolution and size of the image (S20). After S20, the image forming apparatus 100 performs output γ correction processing on the image data of R′G′B ′ based on the result of the region separation processing (S21). After S21, the image forming apparatus 100 performs a preview display based on the image data of R'G'B '(S22). Then, after S22, when a command indicating print permission is input from the user (YES in S23), image forming apparatus 100 reads RGB image data stored in storage device 107 again, and this image. Printing is performed by executing the processing of S9 to S16 based on the data. On the other hand, when a command indicating print cancellation is input from the user after S22 (NO in S23), image forming apparatus 100 ends the process.

(2) Facsimile transmission mode (2-1) During transmission processing (for image transmission job)
FIG. 7 is a block diagram illustrating the same image forming apparatus 100 as the image forming apparatus 100 of FIG. 1, and is a diagram illustrating a flow of image data when performing transmission processing in the facsimile transmission mode. An A / D (analog / digital) conversion unit 2, a shading correction unit 3, an input processing unit 4, a document type automatic discrimination unit 5, a region separation processing unit 6, a compression unit 7, a region separation signal compression unit 8, and a decoding unit. Since the process of 9 is the same as in the case of the copier mode, the description thereof is omitted below.

  In the facsimile transmission mode, the region separation signal decoding unit 10 reads and decodes the region separation signal code from the storage device 107 and transmits the decoded region separation signal to the spatial filter unit 15.

The image quality adjustment unit 11 converts the RGB image data output from the decoding unit 9 into K image data (a value indicating gray shades). This conversion is performed by using a predetermined matrix coefficient or the following equation 2.
Luminance value (value of K image data) = 0.299r + 0.587 g + 0.114b Equation 2
r is a value (density value) of red image data, g is a value of green image data, and b is a value of blue image data.

  The two-color processing unit 12, the color correction unit 13, and the black generation / undercolor removal unit 14 do not perform any processing on the K image data (signal) output from the image quality adjustment unit 11, and this K The image data is transferred to the subsequent spatial filter unit 15 as it is (through).

  The spatial filter unit 15 performs spatial filter processing (enhancement processing, smoothing processing, etc.) on the K image data based on the region separation signal using a digital filter. The scaling unit 16 performs scaling processing on the K image data according to the transmission resolution. The output tone correction unit 17 performs output γ correction processing (γ correction for outputting to a recording medium such as paper) on the K image data output from the scaling unit 16. The halftone generator 18 converts the K image data into binarized image data by, for example, an error diffusion method. The binarized image data is rotated as necessary by a rotation processing unit (not shown), compressed in a predetermined format by a compression / decompression processing unit (not shown), and stored in a memory (not shown). .

  After that, when the transmitting apparatus (for example, modem) 106 performs a transmission procedure with the other party and secures a transmittable state, the binary image data stored in the memory is compressed in a predetermined format. Necessary processing such as reading and compression format change is performed, and the binary image data is sequentially transmitted to the other party via a communication line.

(2-2) Preview Display FIG. 8 is a block diagram showing the same image forming apparatus 100 as the image forming apparatus 100 of FIG. 1, and shows the flow of image data when preview display processing is performed in the facsimile transmission mode. It is a figure. Note that preview display in the facsimile transmission mode means processing for performing preview display of an image to be transmitted by facsimile before facsimile transmission.

  At the time of preview display, the A / D conversion unit 2, the shading correction unit 3, the input processing unit 4, the document type automatic discrimination unit 5, the region separation processing unit 6, the compression unit 7, the region separation signal compression unit 8, the decoding unit 9, Since the processing of the region separation signal decoding unit 10, the image quality adjustment unit 11, and the spatial filter unit 15 is the same as that in the facsimile transmission processing, the description thereof is omitted. Further, the processes in the two-color processing unit 12, the color correction unit 13, and the black generation / undercolor removal unit 14 are passed through in the same manner as in the facsimile transmission process.

  However, at the time of preview display, unlike the transmission processing, three pieces of K image data are transmitted from the image quality adjustment unit 11 to the image display device 104 as shown in FIG. All are the same value). This is because the image display device 104 having the full color specification requires three values (image data) for one pixel.

  The scaling unit 16 thins out the K image data so that the number of pixels of the image composed of the K image data output from the spatial filter unit 15 matches the number of pixels of the display size of the image display device 104. I do. The magnification unit 16 enlarges an image based on a magnification command (information indicating display magnification, for example, a fixed magnification such as 2 to 4) input from an operation panel (not shown) provided in the image forming apparatus. And reduction processing is performed.

  The output tone correction unit 17 performs γ correction corresponding to the display characteristics of the image display device 104 on the K image data output from the scaling unit 16. Then, the halftone generation unit 18 does not perform any processing on the K image data output from the output tone correction unit 17, and transfers the K image data to the subsequent image display device 104 (through). To do). As a result, the image display device 104 can display a preview of the image to be faxed based on the K image data.

  In the preview display process in the facsimile transmission mode, the image quality adjustment unit 11 converts RGB image data into three K image data. However, the present invention is not limited to such a form. For example, up to the output gradation correction unit 17, image processing is performed without converting RGB image data into K image data, and the output gradation correction unit 17 The output RGB image data may be converted into K image data by a browser.

(2-3) Operation / non-operation of each block As described above, during the transmission processing in the facsimile transmission mode, the two-color processing unit 12 and the color correction unit among the image quality adjustment unit 11 to the halftone generation unit 18. 13. The black generation / undercolor removal unit 14 does not operate, but all other blocks operate (see FIG. 7). On the other hand, at the time of preview display in the facsimile transmission mode, among the image quality adjustment unit 11 to halftone generation unit 18, the two-color processing unit 12, the color correction unit 13, the black generation / undercolor removal unit 14, and the halftone generation. The unit 18 does not operate, but all other blocks operate (see FIG. 8).

(2-4) Processing Procedure Next, an example of a processing procedure in the facsimile transmission mode will be described. When a user sends a fax transmission command when “Preview Display Available” is not set in the image forming apparatus 100, the image data is processed as shown in FIG. Will be sent to.

  On the other hand, when a fax transmission command is input by the user when “preview display is present” is set in the image forming apparatus 100, the image data is processed as shown in FIG. The image data is stored in the storage device 107, and a preview of the image data is displayed on the image display device 104. Then, when a command indicating transmission permission is input from the user while the preview is displayed, the image data in the storage device 107 is read, and the read image data is decoded as shown in FIG. The data is processed by the unit 9 to the halftone generation unit 18 and transmitted to the external device by the transmission device 106.

(3) Facsimile reception mode (3-1) During print processing (for image print jobs)
FIG. 9 is a block diagram illustrating the same image forming apparatus 100 as the image forming apparatus 100 in FIG. 1, and is a diagram illustrating a flow of image data when performing a printing process in the facsimile reception mode.

  When receiving a facsimile, the receiving apparatus 105 receives K image data (1 bit) transmitted from the other party while performing a communication procedure. The K image data received by the receiving apparatus 105 is subjected to decompression processing by a compression / expansion processing unit (not shown), and rotation processing is performed as necessary by a rotation processing unit (not shown). A resolution conversion unit (not shown) performs resolution conversion processing as necessary. Thereafter, the image data is temporarily stored in the storage device 107.

  Further, the image data written in the storage device 107 is delivered to the decoding unit 9 of the image processing apparatus 102 by the control unit 108. Decoding unit 9, image quality adjustment unit 11, colorization processing unit 12, color correction unit 13, black generation / under color removal unit 14, spatial filter unit 15, scaling unit 16, output tone correction unit 17, and halftone generation The unit 18 does not perform any processing on the image data sent from the storage device 107, and delivers (through) the image data as it is to the subsequent image output device 103. The image output device 103 forms an image on a recording medium (for example, paper) based on the K image data sent from the halftone generation unit 18. Note that when the printing process is performed in the facsimile reception mode, the image processing is not performed as described above. Therefore, the image data stored in the storage device 107 may be directly output to the image output device 103.

(3-2) Preview Display FIG. 10 is a block diagram showing the same image forming apparatus 100 as the image forming apparatus 100 of FIG. 1, and shows the flow of image data when preview display processing is performed in the facsimile reception mode. It is a figure. Note that the preview display in the facsimile reception mode means a process for previewing an image to be printed before printing the image of the image data when the image data is received by the facsimile.

  Even during the preview display in the facsimile reception mode, the image data written in the storage device 107 is delivered to the decoding unit 9 of the image processing apparatus 102 by the control unit 108 as in the printing process in the facsimile reception mode. The decoding unit 9 does not perform any processing on the image data sent from the storage device 107 and delivers (through) the image data to a bit number conversion processing unit (not shown). Then, the bit number conversion processing unit converts the bit number of the image data received from the decoding unit 9 (for example, conversion from 1 bit to 8 bits), and delivers the bit number converted image data to the subsequent image quality adjustment unit 11. . That is, although not shown, a bit number conversion processing unit is provided between the decoding unit 9 and the image quality adjustment unit 11 in FIG.

  As shown in FIG. 10, when one K image data is input for each pixel, the image quality adjustment unit 11 generates and outputs three K image data (all have the same value). This is because the image display device 104 having a full color specification requires three values for one pixel.

  Thereafter, the two-color processing unit 12, the color correction unit 13, and the black generation / under color removal unit 14 do not perform any processing on the K image data sent from the image quality adjustment unit 11, and the image data As it is to the subsequent spatial filter unit 15 (through). The spatial filter unit 15 performs a blurring process or the like on the K image data using a digital filter.

  The scaling unit 16 thins out the K image data so that the number of pixels of the image composed of the K image data output from the spatial filter unit 15 matches the number of pixels of the display size of the image display device 104. I do. Further, in the scaling unit 16, based on a scaling command (information indicating display magnification, for example, a fixed magnification such as 2 to 4) input from an operation panel (not shown) provided in the image forming apparatus 100. Enlargement or reduction processing is performed.

  The output tone correction unit 17 performs output γ correction processing corresponding to the display characteristics of the image display device 104 on the K image data output from the scaling unit 16. Then, the halftone generation unit 18 does not perform any processing on the K image data output from the output tone correction unit 17 and transfers (through) the image data as it is to the subsequent image display device 104. . As a result, the image display device 104 can display a preview of the image received by fax based on the K image data.

(3-3) Operation / non-operation of each block As described above, the image quality adjustment unit 11 to the halftone generation unit 18 do not operate during the printing process in the facsimile reception mode (see FIG. 9). On the other hand, at the time of preview display in the facsimile reception mode, among the image quality adjustment unit 11 to halftone generation unit 18, the two-color processing unit 12, the color correction unit 13, the black generation / undercolor removal unit 14, and the halftone generation The unit 18 does not operate, but all other blocks operate (see FIG. 10).

(3-4) Processing Procedure Next, an example of a processing procedure in the facsimile reception mode will be described. When image data is received by facsimile in the image forming apparatus 100, the received image data is temporarily written in the storage device 107. Here, there is a time lag from when the image data is written in the storage device 107 to when the image is printed. When a “preview command” is input by the user during this time lag, the image data is not shown in FIG. 10, the image preview of the image data is displayed on the image display device 104. Further, when printing an image, it is processed according to the flow shown in FIG. 9, and the image of the image data is printed by the image output device 103.

(4) Image transmission mode (4-1) During transmission processing (during image transmission job)
When the image forming apparatus 100 is operated during the transmission processing in the image transmission mode, the image input apparatus 101, the A / D (analog / digital) conversion unit 2, the shading correction unit 3, the input processing unit 4, and the document type automatic discrimination unit 5 are used. The processing contents of the region separation processing unit 6, the compression unit 7, the region separation signal compression unit 8, and the decoding unit 9 are the same as those in the copier mode. Note that the region separation signal decoding unit 10 supplies region separation signals to the spatial filter unit 15 and the output tone correction unit 17.

  Then, the image quality adjustment unit 11 performs undercolor removal and color balance adjustment, and the color correction unit 13 performs R "G" B "image data (for example, suitable for display characteristics of display devices that are widely used) (for example, sRGB data), and spatial filter processing (enhancement processing, smoothing processing) using a digital filter is performed in the spatial filter unit 15 based on the region separation signal. In the output tone correction unit 17, for example, the character region is corrected using the gamma curve of FIG. The correction using the gamma curve of a) is performed, and the two-color processing unit 12 and the black generation / under color removal unit 14 do not perform processing on the input image data, and this image data is used as it is. Through to the next block That. Therefore, the output from the output tone correction section 17 is image data of the R "G" B ".

  Further, the R "G" B "image data output from the output tone correction unit 17 is converted into an image file such as a PDF file by a format conversion processing unit (not shown), and scan to image transmission mode. In the e-mail mode, the image file is attached to an e-mail by a mail processing unit (job device) (not shown), and the e-mail is transmitted to the other party via the network. In the scan to ftp mode, the image file is transmitted to a predetermined folder, and in the scan to usb mode of the image transmission mode, the image file is transmitted to a predetermined USB memory.

(4-2) Preview Display When the image forming apparatus 100 is operated during preview display in the image transmission mode, the image input device 101, the A / D (analog / digital) conversion unit 2, the shading correction unit 3, and the input processing unit. 4. Document type automatic discrimination unit 5, region separation processing unit 6, compression unit 7, region separation signal compression unit 8, decoding unit 9, region separation signal decoding unit 10, image quality adjustment unit 11, and colorization processing unit 12 The contents are the same as when transmitting in the image transmission mode.

  Then, at the time of preview display in the image transmission mode, the color correction unit 13 performs processing for converting the RGB image data into R′G′B ′ image data that matches the color space of the image display device 104.

  After that, as in the transmission, spatial filter processing (enhancement processing, smoothing processing) by a digital filter is performed in the spatial filter unit 15 based on the region separation signal. The scaling unit 16 performs a thinning process so as to match the size of the image display device 104. Further, in the output tone correction unit 17, for example, correction using the gamma curve of FIG. 5B is performed on the character region, and the gamma curve of FIG. Correction using is performed.

  Then, the R′G′B ′ image data output from the output tone correction unit 17 is supplied to the image display device 104, and the image display device 104 performs a preview display based on the R′G′B ′ image data. Do.

  The document type automatic determination unit 5 may perform the above-described automatic color determination process (ACS) also during the transmission process in the image transmission mode and during the preview display. Further, the document type automatic determination unit 5 determines not only whether the document image is a color document or a monochrome document, but also a monochrome document during transmission processing in the image transmission mode and during preview display. For a thing, a process for determining whether it is a binary image (an image composed of binary values of white and black) or a gray scale image (an image having gradation) may be performed. This determination processing method will be briefly described below. First, the document type automatic determination unit 5 creates a frequency distribution of pixel values for all pixels determined to be monochrome pixels (monochrome pixels) for an image determined to be a monochrome document. Then, the document type automatic discrimination unit 5 determines that the frequency distribution is mainly composed of two peaks, ie, a white peak and a black peak, and determines that the image is a binary image. It is determined as an image (image having gradation).

  Further, when the document type automatic determination unit 5 determines that the document image is a grayscale image, the image forming apparatus 100 identifies identification information (for example, “grayscale” characters) for allowing the user to recognize that the document image is a grayscale image. ) May be displayed on the image display device 104. Thereby, the user can recognize that the document to be transmitted is a gray scale image. Note that the identification information for allowing the user to recognize that the image is a grayscale image is displayed together with the preview image so as not to overlap the preview image, as shown in FIG.

(5) Modification In the image forming apparatus 100 shown in FIG. 1, the compressed image data (encoded code) and the region separation signal code are stored in the storage device 107 in association with each other. However, like the image forming apparatus 100a shown in FIG. 11, after the image data is read by the image input device 101, the read image data is encoded and temporarily stored before the region separation process and the document type determination process. The document type determination process and the area separation process may be performed on the image data stored in the apparatus 107 and read from the storage apparatus 107 and decoded.

  The image forming apparatus 100 shown in FIG. 1 can execute an image filing mode (image filing job) while a job such as a copier mode, a print mode, a facsimile transmission mode, a facsimile reception mode, and an image transmission mode is selected. Good. In this image filing mode, an image file (JPEG, TIFF file, etc.) is created based on image data obtained by the image input apparatus 101 or image data received from outside during job selection such as copier mode. In this mode, the image file is stored in the storage device 107.

  Here, at the time of filing in the image filing mode, image data obtained by the image input device 101 or image data received from the outside is converted into an image file (JPEG, TIFF file, etc.) by the image processing device 102, and thereafter The image file is stored in the storage device 107 by a filing processing unit (job device) (not shown).

  Also, when previewing while selecting each job (copier mode, print mode, facsimile transmission mode, etc.), the image data obtained by the image input device 101 or from the outside regardless of whether the image filing mode is executed or not. The received image data is processed by the image processing apparatus 102 and then sent to the image display apparatus 104. Further, when previewing during the selection of each job, the image processing executed by the image processing apparatus 102 is the same regardless of whether or not the image filing mode is executed. For example, when the copier mode preview is displayed, the processing content of the image processing apparatus 102 is as shown in FIG. 3 regardless of whether or not the image filing mode is executed. In addition, when the preview is displayed in the facsimile transmission mode, the processing contents of the image processing apparatus 102 are as shown in FIG. 8 regardless of whether or not the image filing mode is executed.

(6) Advantages of the image processing apparatus according to the present embodiment The image processing apparatus 102 according to the present embodiment provides an image to an image output apparatus (job apparatus, printing apparatus) 103 that performs a print job (copier mode, print mode). The image data is supplied to the image display device 104 in order to supply data and display a preview on the image display device 104 before execution of the print job.

  The image processing apparatus 102 performs first image processing performed on the image data supplied to the image output apparatus 103, and first image processing performed on the image data supplied to the image display apparatus 104. A first image processing unit that executes a second image processing different from the first image processing using a circuit area common to both the image processing. Here, as an example of the first image processing unit, there is a color correction unit 13 in the copier mode and the full color mode. In this color correction unit 13, the conversion process from RGB to CMY (first image process) and the conversion process from RGB to R′G′B ′ (second image process) are performed in a common circuit area. Because.

  As a result, not only image processing for print processing and the like, but also an image processing apparatus that performs image processing for preview before print processing has an effect that the circuit scale of the image processing circuit can be suppressed.

  In the present embodiment, when printing in the copier mode and the full color mode, the color correction unit 13 reads image data (RGB) for additive color mixing that is read by the scanner and according to the characteristics of the scanner. A process of converting into image data (CMY) for subtractive color mixing according to the characteristics is performed. On the other hand, during the copier mode and full color mode preview, the color correction unit 13 reads the image data (RGB) for additive color mixing that is read by the scanner and that corresponds to the characteristics of the scanner according to the characteristics of the image display device 104. Further, a process of converting into image data (R′G′B ′) for additive color mixing is performed. That is, during preview display, image data for additive color mixing corresponding to the characteristics of the scanner is directly converted into image data for additive color mixing corresponding to the characteristics of the image display device 104. Therefore, according to the image processing apparatus 102 of the present embodiment, one-time nonlinear conversion from RGB image data to R′G′B ′ image data is performed during preview display in the copier mode and the full color mode. Further, unlike the configuration of Japanese Patent Laid-Open No. 9-135316, non-linear conversion is not performed a plurality of times, so that accumulation of conversion errors can be suppressed and a decrease in color reproducibility can be suppressed. In JP-A-9-135316, conversion from RGB data to CMY data, conversion from CMY data to CMYK data, conversion from CMYK data to CMY data, and conversion from CMY data to RGB Since conversion to data is performed a total of four times, conversion errors are accumulated and color reproducibility is degraded.

  In the present embodiment, the nonlinear conversion is performed at the time of preview in the copier mode and single color mode, or at the preview in the copier mode and two color mode, but the number of nonlinear conversions is only two. Therefore, the color reproducibility can be prevented from lowering as compared with the configuration disclosed in Japanese Patent Laid-Open No. 9-135316 in which nonlinear conversion is performed four times in total.

  Further, in the present embodiment, when printing in the copier mode and the full color mode, the black generation / under color removal unit 14 performs processing for converting the CMY image data into the CMYK image data, while the copier mode and the full color mode. When the preview is displayed, the black generation / under color removal unit 14 outputs the R′G′B ′ without any processing. As a result, printing image data that needs to be converted from CMY to CMYK (black generation / undercolor removal processing) and preview image data that does not need to be subjected to black generation / undercolor removal processing. The image data path in the image processing circuit can be shared, and the circuit configuration can be simplified.

  In the image processing apparatus 102 of the present embodiment, it is possible to perform image processing based on the determination result of the document type automatic determination unit 5, image processing based on the processing result of the region separation processing unit 6, and background removal processing. The effects of these processes are also reflected in the preview image displayed on the image display device 104.

  In this embodiment, image data supplied to the above-described job apparatus is executed on a computer-readable recording medium in which program code (execution format program, intermediate code program, source program) to be executed by a computer is recorded. The first image processing that is performed and the second image processing that is performed on the image data supplied to the display device and that is different from the first image processing are performed using a circuit area common to both image processing. An image processing method may be recorded. As a result, it is possible to provide a portable recording medium on which a program for performing the image processing method is recorded.

  In the present embodiment, as the recording medium, a memory (not shown) such as a ROM itself may be a program medium because processing is performed by a microcomputer. However, it may be a program medium provided with a program reading device as an external storage device and readable by inserting a recording medium therein.

  In any case, the stored program code may be configured to be accessed and executed by the microprocessor, or in any case, the program code is read and the read program code is the microcomputer. The program code may be downloaded to a program storage area (not shown) and executed. It is assumed that this download program is stored in the main device in advance.

  Here, the program medium is a recording medium configured to be separable from the main body, such as a tape system such as a magnetic tape or a cassette tape, a magnetic disk such as a flexible disk or a hard disk, a CD-ROM / MO / MD / DVD, or the like. Semiconductors such as optical discs, IC cards (including memory cards) / optical cards, etc., or mask ROM, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), flash ROM, etc. It may be a medium that carries a fixed program code including a memory.

  In the present embodiment, since the system configuration is such that a communication network including the Internet can be connected, a medium that dynamically carries the program code so as to download the program code from the communication network may be used. When the program code is downloaded from the communication network in this way, the download program may be stored in the main device in advance, or may be installed from another recording medium. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission. The recording medium is read by a program reading device provided in a digital color image forming apparatus or a computer system, whereby the above-described image processing method is executed.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and the embodiments can be obtained by appropriately combining the respective technical means disclosed in the above-described embodiments. The form is also included in the technical scope of the present invention.

  The image processing apparatus of the present invention can be used for an apparatus that handles image data, but is particularly suitable for a multifunction machine, a copying machine, a printer, and a facsimile machine.

FIG. 2 is a block diagram illustrating an image forming apparatus according to the present exemplary embodiment, and is a block diagram illustrating a flow of image data when printing processing is performed in a copier mode and a full color mode. (A) is a block diagram showing a part of the image processing apparatus when printing processing is performed in the copier mode and the single color mode, and (b) is a printing in the copier mode and the two-color mode. It is the block diagram which showed a part in the image processing apparatus at the time of a process being performed. FIG. 2 is a block diagram illustrating an image forming apparatus according to an exemplary embodiment, and is a block diagram illustrating a flow of image data when preview display processing is performed in a copier mode and a full color mode. (A) is a block diagram showing a part of the image processing apparatus when preview display is performed in the copier mode and the single color mode, and (b) is a preview in the copier mode and the two-color mode. It is the block diagram which showed a part in the image processing apparatus at the time of display. (A) is the figure which showed an example of the gamma curve according to the display characteristic of an image display apparatus. (B) is a figure which showed the gamma curve for displaying a character clearly as a continuous line, and showed the gamma curve according to the display characteristic of the image display apparatus with the broken line. 6 is a flowchart illustrating a processing procedure of the image forming apparatus when a copier mode and a full color mode are selected. FIG. 2 is a block diagram illustrating an image forming apparatus according to the present exemplary embodiment, illustrating a flow of image data when performing transmission processing in a facsimile transmission mode. FIG. 2 is a block diagram illustrating an image forming apparatus according to the present exemplary embodiment, illustrating a flow of image data when preview display processing is performed in a facsimile transmission mode. 1 is a block diagram illustrating an image forming apparatus according to an exemplary embodiment, and is a diagram illustrating a flow of image data when print processing is performed in a facsimile reception mode. FIG. 2 is a block diagram illustrating an image forming apparatus according to the present exemplary embodiment, illustrating a flow of image data when preview display processing is performed in a facsimile reception mode. It is a block diagram showing a modification of the image forming apparatus of the present embodiment. (A) is a diagram showing an image displayed in preview in the copier mode, and (b) is a diagram showing an image displayed in preview in the image transmission mode.

Explanation of symbols

13 color correction unit (first image processing unit)
14 Black generation / under color removal unit (second image processing unit)
100 Image forming apparatus 101 Image input apparatus (scanner)
102 image processing apparatus 103 image output apparatus (printing apparatus, job apparatus)
104 Image display device (display device)
105 receiving device 106 transmitting device (job device)
107 storage device 108 control unit

Claims (8)

Supplying image data of an image handled in the job to a job device that executes any one of an image print job, an image transmission job, and an image filing job;
In an image processing apparatus that supplies the image data to the display device in order to display a preview of the image on the display device before execution of the job,
A first image process executed on the image data supplied to the job apparatus; and a second image process executed on the image data supplied to the display apparatus and different from the first image process. An image processing apparatus comprising a first image processing unit that executes using a circuit area common to both image processes. Supplying image data of an image handled in the image print job to a printing apparatus which is a job apparatus that executes the image print job;
The image print job is a copy process for printing an image based on image data read by a scanner,
The first image processing is processing for converting image data for additive color mixing that is read by the scanner and corresponding to the characteristics of the scanner into image data for subtractive color mixing that corresponds to the characteristics of the printing apparatus,
2. The second image processing is processing for converting image data for additive color mixing corresponding to characteristics of the scanner into image data for additive color mixing corresponding to characteristics of the display device. An image processing apparatus according to 1. The first image processing is conversion processing for converting RGB image data into CMY image data.
A second image processing unit for inputting the image data output from the first image processing unit;
The second image processing unit converts the CMY image data after the first image processing into CMYK image data and outputs the converted image data, while the second image processing is performed on the image data after the second image processing is performed. The image processing apparatus according to claim 2, wherein the image is output without being processed.   The image data necessary for a job can be supplied to any of a job device that executes an image print job, a job device that executes an image transmission job, and a job device that executes an image filing job. Image processing device.   An image forming apparatus comprising the image processing apparatus according to claim 1 and the job apparatus, wherein the job apparatus is a printing apparatus. Supplying image data of an image handled in the job to a job device that executes any one of an image print job, an image transmission job, and an image filing job;
In a control method of an image processing apparatus for supplying the image data to the display device in order to display a preview of the image on the display device before execution of the job,
A first image process executed on the image data supplied to the job apparatus; and a second image process executed on the image data supplied to the display apparatus and different from the first image process. A control method for an image processing apparatus, wherein the image processing apparatus is executed by using a circuit area common to both image processes.   A control program for controlling the image processing apparatus according to claim 1 for causing a computer to operate as the first image processing unit.   A computer-readable recording medium on which the control program according to claim 7 is recorded.

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