JP5752390B2 - Image processing apparatus, image forming apparatus, image processing method, image processing program, and computer-readable recording medium - Google Patents

Description

  The present invention relates to an image processing apparatus, an image forming apparatus, an image processing method, an image processing program, and a computer-readable recording medium that display thumbnails and previews of input image data.

  In image forming devices such as copiers and multifunction devices, when scanning a document and performing output such as copy output or transmission output, select various image quality setting items such as document type and bruise adjustment, and then perform operations before output A preview of image data is displayed on the panel. By performing the preview display in this way, it is possible to confirm whether or not an output intended by the user can be obtained, and it is possible to reduce the trouble of re-outputting and wasteful consumption of paper and toner.

  As a technique for displaying copy output image data as a preview, there is a technique proposed in Patent Document 1. Patent Document 1 proposes a technique for matching the colors of an output image and a preview image by performing the following (1) to (3). (1) YMCK output image data is input to a 3 × 4 reverse masking correction circuit and converted into CMY density information. (2) Conversion to RGB signals by a correction circuit for inverse logarithmic conversion, and color correction of the monitor is performed using a 3 × 3 matrix based on the monitor color temperature, the color development characteristics of the monitor, and the illumination light. (3) Further, a plurality of γ value correction data are selected and displayed on the monitor.

JP-A-9-37093 (published on February 7, 1997)

  However, in the technique described in Patent Document 1, YMCK output image data is converted into CMY density information, and further converted into RGB signals by an inverse logarithmic conversion correction circuit. Therefore, processing time is required until preview display. .

  In Patent Document 1, RGB data is once 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. Times nonlinear transformation. As described above, since a plurality of nonlinear transformations are performed before the creation of the preview image, the color reproducibility at the time of preview is deteriorated.

  Also, a preview image of copy output, that is, an image subjected to image quality adjustment processing for copy output can be confirmed, but a scanned document cannot be confirmed. For example, it is preferable that the output document, the vertical direction of the document, the order of a plurality of documents, and the like can be confirmed without performing complicated processing such as image quality adjustment processing set by the user. However, Patent Document 1 does not consider processing for confirming a scanned document.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a display for confirming a document read by an image input device and an image output by the image output device when performing image output. An object of the present invention is to provide an image processing apparatus or the like that enables accurate preview display in a short time.

  In order to solve the above problems, the image processing apparatus of the present invention performs image processing on image data obtained by reading an original image by the image input apparatus, and displays the image data when the image output apparatus outputs the image data. An image processing apparatus to be supplied to an apparatus, wherein the image data to be supplied to the image display apparatus is based on a color reproduction characteristic of the image input apparatus and a color reproduction characteristic of the image display apparatus. A first color correction unit that performs the first color correction, and a second color correction characteristic based on the color reproduction characteristics of the image output device and the color specification reproduction characteristics of the image display device for the image data on which the first color correction processing has been performed. A second color correction unit that performs color correction processing, and supplies the image data subjected to the first color correction processing and the image data subjected to the second color correction processing to the image display device It is characterized by doing.

  According to the above configuration, the image data supplied to the image display device is subjected to the first color correction process based on the color reproduction characteristics of the image input device and the color specification reproduction characteristics of the image display device. Therefore, it is possible to perform processing so that the color of the image displayed on the image display device is close to the color of the original image read by the image input device, that is, the difference between these colors is reduced.

  Further, according to the above configuration, the second color correction processing based on the color reproduction characteristics of the image output device and the color reproduction characteristics of the image display device is performed on the image data subjected to the first color correction processing. Is done. Therefore, the color of the image displayed on the image display device is close to the color of the image to be printed, that is, the difference between these colors can be reduced.

  Then, the image data subjected to the first color correction process and the image data subjected to the second color correction process are supplied to the image display device. Therefore, the image display device displays an image having a color close to the read original and an image having a color close to the output from the image output device.

  Therefore, by displaying the image data subjected to the first color correction processing on the image display device, the user can accurately confirm that the original read by the image input device is correct. it can. Further, the first color correction process is based on the color reproduction characteristics of the image input device and the color reproduction characteristics of the image display device, that is, the process based on the color reproduction characteristics of the image output device is not performed. An image having a color close to that of the original image can be displayed on the image display device in a short time.

  Further, the image data that has been subjected to the second color correction process is displayed on the image display device, so that the user can confirm the image of the output product in a short time with high accuracy.

  As described above, the user can confirm the image of the document and the image of the output product with high accuracy in a short time before output by the image output apparatus.

  Here, in the image processing apparatus of the present invention, the image output apparatus may be a printing apparatus that executes image printing. When the image output device is a printing device, an image having a color close to the color of the original image and an image having a color close to the color of the printed material are displayed on the image display device before printing. Therefore, the user can accurately check the image of the original and the image of the printed matter before printing.

  In the image processing apparatus of the present invention, in addition to the above configuration, the first color correction unit may perform the first color correction processing by matrix calculation.

  When color correction processing is performed using a lookup table, the color correction accuracy can be improved, but the memory capacity increases. Here, when sequentially displaying the image data of the document read by the image input device, it is only necessary to confirm the top and bottom direction, order, contents, and the like of the document. Therefore, the first color correction unit uses the matrix coefficient to perform the first color correction process so that the color of the image displayed on the image display device is close to the color of the document image. That is, according to the above configuration of the present invention, the memory capacity can be reduced, and the color difference between the original image and the image displayed on the image display device can be reduced.

  In the image processing apparatus of the present invention, in addition to the above configuration, each of the first color correction unit and the second color correction unit accepts an instruction input indicating whether operation is necessary, and executes the correction process according to the instruction input. Yes or no.

  The operation of the first color correction process in the first color correction unit and the operation of the second color correction process in the second color correction unit can be selected. In other words, the user can select the display of the color image close to the original after the first color correction processing and the display of the color image close to the print output image after the second correction processing, and display either one of them. You may confirm it, you may display both, and it is not necessary to display either. Thus, according to the above configuration, it is possible to provide an image processing apparatus that is easy to use for the user.

  In the image processing apparatus of the present invention, in addition to the above configuration, the second color correction unit may also be used as a color correction processing unit that performs color correction on image data supplied to the printing apparatus.

  According to the above configuration, the color correction processing unit conventionally provided in the image processing apparatus is also used as the second color correction unit, so that a new circuit for performing the second color correction process is not required, and the circuit scale of the apparatus is increased. An increase in size can be suppressed.

  In order to solve the above problems, an image forming apparatus according to the present invention includes any one of the image processing apparatuses described above, an image input apparatus that reads an original image, an image output apparatus that outputs image data, and an image data display. And an image display device for performing the above.

  According to the above configuration, an image with a small difference from the color of the original image can be displayed in a short time on the image display device, and an image with a small difference from the color of the output image can be displayed in a short time. can do. In this way, an image forming apparatus is provided in which a user can accurately confirm an image close to the color of an original image and an image close to the color of an output product in a short time before output by the image output device. Can do.

  In order to solve the above problems, the image processing method of the present invention performs image processing on image data obtained by an image input device reading a document image, and outputs the image data when the image output device outputs the image data. An image processing method for supplying to an apparatus, wherein the image data supplied to the image display device is based on a color reproduction characteristic of the image input device and a color reproduction characteristic of the image display device. And a second color correction step based on a color reproduction characteristic of the image output device and a color reproduction characteristic of the image display device for the image data subjected to the first color correction process. A second color correction step for performing color correction processing, and supplying the image data subjected to the first color correction processing and the image data subjected to the second color correction processing to the image display device Features to do It is.

  According to the above method, the same effect as that of the image processing apparatus is obtained, the difference between the color of the original image and the color of the image displayed on the image display apparatus is reduced, and the color and image of the output product It is possible to provide an image processing method that reduces a difference from the color of an image displayed on a display device.

  By displaying the image data subjected to the first color correction processing on the image display device, the user can accurately confirm that the original read by the image input device is correct. Further, the first color correction process is based on the color reproduction characteristics of the image input device and the color reproduction characteristics of the image display device, that is, the process based on the color reproduction characteristics of the image output device is not performed. An image having a color close to that of the original image can be displayed on the image display device in a short time.

  Further, the image data that has been subjected to the second color correction process is displayed on the image display device, so that the user can confirm the output image accurately in a short time.

  As described above, according to the above method, the user can accurately confirm the image of the original and the image of the output product in a short time before output by the image output apparatus.

  The image processing apparatus of the present invention may be realized by a computer. In this case, an image processing program for causing the image processing apparatus to be realized by a computer by causing the computer to operate as each unit in the image processing apparatus. A computer-readable recording medium on which the image processing program is recorded also falls within the scope of the present invention.

  According to these configurations, the same operational effects as those of the image processing apparatus can be realized by causing the computer to read and execute the image processing program.

  As described above, the image processing apparatus according to the present invention is based on the color reproduction characteristics of the image input apparatus and the color specification reproduction characteristics of the image display apparatus based on the image data supplied to the image display apparatus. Based on the color reproduction characteristic of the image output device and the color reproduction characteristic of the image display device for the first color correction unit that performs color correction processing and the image data on which the first color correction processing has been performed. A second color correction unit that performs a second color correction process, the image data subjected to the first color correction process, and the image data subjected to the second color correction process to the image display Supply to the device.

  According to the above configuration, the image data supplied to the image display device is subjected to the first color correction process based on the color reproduction characteristics of the image input device and the color specification reproduction characteristics of the image display device. Therefore, it is possible to perform processing so that the color of the image displayed on the image display device is close to the color of the original image read by the image input device, that is, the difference between these colors is reduced.

  Further, according to the above configuration, the second color correction processing based on the color reproduction characteristics of the image output device and the color reproduction characteristics of the image display device is performed on the image data subjected to the first color correction processing. Is done. Therefore, the color of the image displayed on the image display device is close to the color of the image to be printed, that is, the difference between these colors can be reduced.

  Then, the image data subjected to the first color correction process and the image data subjected to the second color correction process are supplied to the image display device. Therefore, the image display device displays an image having a color close to the read original and an image having a color close to the output from the image output device.

  Therefore, by displaying the image data subjected to the first color correction processing on the image display device, the user can accurately confirm that the original read by the image input device is correct. it can. Further, the first color correction process is based on the color reproduction characteristics of the image input device and the color reproduction characteristics of the image display device, that is, the process based on the color reproduction characteristics of the image output device is not performed. An image having a color close to that of the original image can be displayed on the image display device in a short time.

  Further, the image data that has been subjected to the second color correction process is displayed on the image display device, so that the user can confirm the image of the output product in a short time with high accuracy.

  As described above, the user can confirm the image of the document and the image of the output product with high accuracy in a short time before output by the image output apparatus.

It is the block diagram which showed the image processing apparatus of this embodiment, (a) is a data flow at the time of displaying on an image display apparatus after a 1st color correction process, (b) is after a 2nd color correction process. The flow of the data at the time of displaying with an image display apparatus is shown. It is a figure which shows an example of the gamma curve matched with the characteristic of the image display apparatus which the gamma correction part with which the said image processing apparatus was equipped is used. It is the flowchart which showed the process sequence of the said image processing apparatus. 3 is a diagram illustrating an example of an initial screen on an operation panel included in the image forming apparatus according to the present exemplary embodiment. FIG. It is a figure which shows an example of the setting screen of the preview display on the said operation panel. 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 in the copier mode and the two-color mode. FIG. 3 is a block diagram illustrating a part of the image processing apparatus when a printing process is performed. FIG. 2 is a block diagram illustrating the image forming apparatus, 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 copier mode and single color mode, and (b) is in copier mode and two-color mode. It is the block diagram which showed a part in the said image processing apparatus at the time of a preview display being performed. (A) is a figure which showed an example of the gamma curve according to the display characteristic of the image display apparatus used by the output gradation correction | amendment part with which the said image processing apparatus was equipped. (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. It is a block diagram showing a modification of the image forming apparatus of the present embodiment.

(Image processing device)
An embodiment of an image processing apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the main configuration of the image processing apparatus 1 of the present embodiment. The image processing apparatus 1 performs image processing on image data obtained by the image input apparatus 2 reading a document image, and supplies the image data to an image output apparatus 3 that outputs an image. When the image output device 3 outputs an image, the image processing device 1 also supplies the image data to the image display device 4 to display the image. Here, a configuration and processing when the image processing apparatus 1 displays an image on the image display apparatus 4 will be described. Other configurations and processes will be described later in the description of the image forming apparatus.

  As shown in FIG. 1, the image processing apparatus 1 includes a first color correction unit 11, a gamma correction unit 12, a resolution conversion unit 13, and a second color correction unit 14. Here, FIG. 1A is a block diagram showing the flow of data when the image data is color-converted to a color (color) close to that of the document and supplied to the image display device 4. FIG. 1B is a block diagram showing a data flow when image data is converted into a color (color) similar to output data and the image data is displayed on the image display device 4.

  The image input device 2 is an image reading unit that reads an original and generates image data including RGB signals. The image input device 2 is configured by a scanner having a CCD (Charge Coupled Device), for example.

  The first color correction unit 11 receives the RGB signal of the image data obtained by scanning the document, and converts the RGB signal value so as to be close to the color of the document (first color conversion process). The input RGB signal is data conforming to the color space of the image input device 2 (scanner). The first color correction unit 11 performs a process of converting the RGB signal into RGB image data suitable for the color space of the image display device 4. In this conversion process, matrix calculation is performed according to the following Equation 1.

When the image input device 2 is for color, each color patch of the color chart document is read by the image input device 2 to obtain RGB data. Further, each patch of the color chart document read by the image input device 2 is displayed on the image display device 4 and measured by a colorimeter to obtain an R′G′B ′ value. Based on the RGB value and R′G′B ′ value obtained in this way, a coefficient for associating the two is obtained by a neural network or a masking calculation coefficient determination method. Note that the image display device 4 preferably displays a reference color based on the L ^* a ^* b ^* value and measures the color in advance to perform color calibration.

Alternatively, L ^* a ^* b ^* values corresponding to RGB data obtained by reading each color patch of the color chart document with the image input device 2 are obtained. At the same time, each patch of the read color chart document is displayed on the image display device 4 and measured by a colorimeter to obtain an L ^* 'a ^* ' b ^* 'value. Based on the L ^* a ^* b ^* value and the L ^* 'a ^* ' b ^* 'value obtained in this way, a coefficient for associating both may be obtained by a neural network or a masking calculation coefficient determination method. . For example, the following values can be used as the coefficient values of Equation 1 above.

  The gamma correction unit 12 performs gamma correction on the RGB signals of the image data in accordance with the characteristics of the image display device 4. FIG. 2 shows a gamma curve in which input RGB signals are associated with output RGB. The gamma value of the gamma curve is set in consideration of the gamma value of the image display device 4. For example, when the gamma value of the image display device 4 is 2.2, the gamma correction unit 12 performs correction using a gamma curve of a gamma value of 0.45 that is the reciprocal of 2.2.

  Since the resolution conversion unit 13 displays the image data on the image display device 4 in a short time, the resolution of the image data formed by the image input device 2 (for example, 1200 dpi, 600 dpi, etc.) and the resolution of the image display device 4 If it is different (for example, 150 dpi, 75 dpi, etc.), a process for reducing the resolution of the image data is performed. The resolution conversion uses, for example, a bilinear method.

  The bilinear method is a method of creating an image with a reduced resolution by using a weighted average value of a plurality of pixels before conversion as a pixel value after conversion. In the present embodiment, the converted resolution is, for example, 75 dpi × 75 dpi. In this case, if the resolution of the input image is 600 dpi × 600 dpi, the resolution is converted to 1/8 resolution by the bilinear method.

  The image data after the resolution conversion is sent to the image display device 4 and displayed as color data close to the original. It is also stored in the storage device 5.

  As shown in FIG. 1B, the second color correction unit 14 performs an actual output product (output image) of the image output device 3 on the RGB signal of the image data read from the storage device 5. The color is converted so as to be close to the color (second color conversion process). In the conversion method, the values of the RGB signals input to the second color correction unit 14 and the values of the RGB signals displayed in a color close to the actual output when displayed on the image display device 4 are obtained. This is realized by creating an associated LUT (lookup table) and looking up an output value from the created LUT. The color-converted image data is supplied to the image display device 4 and displayed as color data close to the color of the output product.

  Note that the image data to be corrected by the second color correction unit 14 at the time of preview display for output is data that has been subjected to the first color correction process, the gamma correction process, and the resolution conversion process.

Specifically, the processing in the second color correction unit 14 is performed as follows. Each color patch of the color chart document is read by the image input device 2, the R′G′B ′ value subjected to the first color correction processing and the gamma correction processing is displayed on the image display device 4, and colorimetry is performed by the colorimeter. L ^* 'a ^* ' b ^* 'value is obtained. Each color patch of the color chart document is read by the image input device 2, printed out by the image output device 3, each color patch printed out is measured by a colorimeter, and L ^* '' a ^* '' b ^* ''Find the value. Based on the correspondence between the L ^* 'a ^* ' b ^* 'value obtained above and the R'G'B' value, R''G 'corresponding to the L ^* ''a ^* ''b ^* ''value Find the 'B' value. Based on the R′G′B ′ value and the R ″ G ″ B ″ value, an LUT that associates the two is created by a neural network or a masking calculation coefficient determination method.

  The image display device 4 is a display (monitor) capable of color display of image data, and is configured by a liquid crystal display, for example.

  The image output apparatus 3 is an apparatus that performs output corresponding to each process in printing, filing, or transmission (e-mail transmission, facsimile transmission). For example, in the case of printing, it is a color printer (printing device) using an electrophotographic method or an inkjet method, and in the case of filing, it is a hard disk capable of recording data, and transmission (e-mail transmission, facsimile transmission) In this case, the device is connected to a telephone line or the Internet and transmits image data to an external device.

  FIG. 3 shows a flowchart of the process flow in the image processing apparatus 1. First, the value of the preview determination symbol P is set to 0 (step S1). Next, it is determined whether or not there is an output preview display instruction input for previewing the output from the user. In the present embodiment, it is assumed that the image forming apparatus 100 including the image processing apparatus 1 is configured so that the user can select whether or not to perform output preview display. For example, the user selects the preview button 401 on the initial screen of the operation panel of the image forming apparatus 100 shown in FIG. 4, and selects the on button 501 on the preview display setting screen shown in FIG. By pressing (touching), it is possible to input to the image processing apparatus 1 to instruct output preview display. Further, the user can input an instruction not to display the output preview to the image processing apparatus 1 by selecting the off button 502 on the preview display setting screen. Also, the user can prevent the output preview from being displayed by not selecting the preview button 401 on the initial screen.

  When the user does not select the preview button 401 on the setting screen or when the user selects the off button 502 on the setting screen for preview display, that is, when there is no output preview display instruction input (NO in S2), the preview determination symbol P Is set to 1 (S3). If the user selects output preview display, that is, if there is an instruction input for output preview display (YES in S2), the value of preview determination symbol P remains 0 and the process proceeds to the next.

  Next, it is determined whether there is a scan-in instruction from the user (S4). In the present embodiment, the image forming apparatus 100 including the image processing apparatus 1 is configured so that the user can select whether or not to scan in. For example, the user selects and inputs scan-in by pressing the scan-in button 402 on the initial screen of the operation panel of the image forming apparatus 100 shown in FIG.

  If there is a scan-in instruction input (YES in S4), it is next determined whether preview determination symbol P = 1 or not (S5).

  When P is not 1 (NO in S5), it is determined that both the document reference image and the output reference image are displayed. Here, the document reference image is image data converted to a color close to that of the document, and the output reference image is image data converted to a color close to the output product. Then, a document reference image that has been subjected to color conversion processing with a color close to that of the document is created (S6), an output reference image that has been subjected to color conversion processing with a color close to that of the output product is created (S7), The image data is displayed in the order of the output reference image (S8).

  If there is a scan-in instruction input (YES in S4) and preview determination symbol P = 1 (YES in S5), it is determined that only the document reference image is displayed, and the color is similar to that of the document. A document reference image subjected to the conversion process is created (S9), and the document reference image is displayed (S10).

  Even when there is no scan-in instruction input (NO in S4), it is determined whether or not the preview determination symbol P = 1 (S11). If P = 1 is not determined in this determination (NO in S11), it is determined that only the output reference image is displayed, and an output reference image obtained by performing color conversion processing on the color close to the output product is generated (S12) and output. A reference image is displayed (S13).

  If P = 1 in the determination of S11 (YES in S11), it is determined that no image is displayed, and color correction processing is performed in accordance with the output (printing, transmission, etc.) of the image output device 3 ( S14), display on the image display device 4 is not performed (S15).

  When the user selects scan-in, the original placed on the ADF or the like of the image input device 2 is sequentially read (scanned), and subjected to first color correction, gamma correction, and resolution conversion processing (displaying the original) Are displayed on the image display device 4 in the order of scanning. In the present embodiment, this image is referred to as a document reference image.

  The user looks at the displayed document reference image, checks the correction of the top and bottom direction of the document, the order, and corrects if there is an error. As a correction method, the image display device 4 may be configured with a touch panel so that the locus of an operation input with a finger or a pen can be recognized, and may be performed as follows. For example, when changing the top / bottom direction of a document, the displayed document is rotated so that the document is in the correct direction (or the direction intended by the user) so that the order of the documents is correct. In addition, correction may be made so as to change the position of the target document.

  Further, at this stage, the user performs condition setting (full color, black and white, single color, two color setting, vividness setting, density setting, etc.) when the document is output by the image output device 3. When these conditions are set and the start button is pressed, the image data stored in the storage device 5 is read, and the processing after the decoding unit in FIG. 1 is performed. At this time, if the user is set to perform output preview display, preview display of the output reference image is performed.

  Next, processing for each operation performed by the user based on the initial screen of the operation panel shown in FIG. 4 is summarized below.

  When the user turns on the preview so that the output preview is displayed on the initial screen of the operation panel and presses the scan-in button 402, color correction is performed so that the read original has a color close to the original (first). Color correction processing) and sequentially displayed on the operation panel. When the user subsequently presses the start button to instruct a start for output in the image output device 3, the process is based on the set conditions, and the color correction process ( The second color correction process) is performed, and the output reference image is displayed on the operation panel.

  When the user turns on the output preview display setting without pressing the scan-in button 402 and presses the start button, color correction processing (second color correction) is performed so that the color becomes close to the output product, and output is performed. A reference image is displayed.

  When the user turns off the preview display setting and presses the scan-in button 402, color correction is performed so that the color is close to that of the read original, and only the process of sequentially displaying the original reference image is performed.

  When the user turns off the preview display setting and presses the start button, image processing for output processing (copy, image transmission, facsimile transmission, etc.) is performed without displaying the original reference image and the output reference image.

(Image forming device)
Next, one form of the image forming apparatus of this embodiment provided with the image processing apparatus 1 of this embodiment is demonstrated based on figures. FIG. 5 is a block diagram illustrating a schematic configuration of the image forming apparatus 100 of the present embodiment. The image forming apparatus 100 is a digital color multi-function peripheral that executes a selected mode when one of a copier mode, a print mode, a facsimile transmission mode, a facsimile reception mode, and an image transmission mode is selected. .

  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 such as a PC 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 a facsimile reception device and an image of the received image data is printed on a sheet. The image transmission mode is (1) a mode in which image data obtained by reading a document is attached to an e-mail and transmitted to a specified address (scan to e-mail mode), and (2) obtained by reading the document. Mode for transmitting image data to a folder designated by the user (scan to ftp mode), (3) Mode for transmitting image data obtained by reading a document 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. However, the mode classification is not limited to the above.

  When the copier mode or the print mode is selected, the user can select a monochrome mode for outputting a monochrome image, a full color mode for outputting a full color image, or a single color for outputting a single color image composed of only one color desired by the user. Either a 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, when the user selects the single color mode in the copier mode or the print 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, the user selects one desired color from R (red), G (green), B (blue), C (cyan), M (magenta), and Y (yellow). It will be.

  In the two-color mode, a chromatic color extraction mode in which a chromatic color is extracted from the image data and the extracted chromatic color is converted to a color designated by the user, and the user designates the color and is designated in the image data. In addition, a color designation mode for converting only the colors of the selected system into a designated color is provided, and either one is selected when the two-color color mode is selected. When red is selected as the designated color in the chromatic color extraction mode, all colors extracted as chromatic colors are converted to red, and achromatic colors are expressed in black. On the other hand, if you select red as the color to be converted and red as the specified color in the color specification mode, the color extracted as the red color is converted to red, and other colors (blue, green, achromatic color, etc.) ) Is converted to black. As in the case of single color, the designated color is one desired color from among R (red), G (green), B (blue), C (cyan), M (magenta), and Y (yellow). 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 shown in FIG. 5, the image forming apparatus 100 includes an image processing device 1, an image input device 2, an image output device 3, an image display device 4, a storage device 5, a reception device 6, a transmission device 7, and a control unit 8. Have.

  The image input device 2 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 2 includes a scanner unit having a CCD (Charge Coupled Device), and an electric 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 1.

  Note that the image input apparatus 2 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 2 reads a document image in full color even when the above-described automatic color discrimination process is performed in the image processing apparatus 1.

  The image processing apparatus 1 is an integrated circuit that performs image processing on image data (image signal) obtained by reading a document with the image input apparatus 2, and includes an ASIC (Application Specific Integrated Circuit). The image processing apparatus 1 has the following configuration, but the configuration described with reference to FIG. 1 is assigned the same number, and the content described above is simplified. As shown in FIG. 5, the image processing apparatus 1 includes an A / D (analog / digital) conversion unit 21, a shading correction unit 22, an input processing unit 23, a document type automatic determination unit 24, a first color correction unit 11, a gamma. Correction unit 12, resolution conversion unit 13, region separation processing unit 25, compression unit 26, region separation signal compression unit 27, decoding unit 28, region separation signal decoding unit 29, image quality adjustment unit 30, two-colorization processing unit 31, Each block includes a dichroic correction unit 14, a black generation / undercolor removal unit 32, a spatial filter unit 33, a scaling unit 34, an output tone correction unit 35, and a halftone generation unit 36. The processing content of each block included in the image processing apparatus 1 will be described in detail later.

  Note that the image processing apparatus 1 performs image processing on the image data sent from the image input apparatus 2 in the copier mode, the facsimile transmission mode, and the image transmission mode. In the print mode, image processing is performed on the image data transmitted from the terminal device. In the facsimile reception mode, image processing is performed on image data received from an external device. The image processing apparatus 1 transmits image data subjected to image processing to the image output apparatus 3 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. 7 to send.

  Further, the image processing apparatus 1 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.

  The image output device (printer) 3 prints (forms) an image of image data sent from the image processing device 1 on a recording medium (for example, paper). Examples of the image output device 3 include a color printer using an electrophotographic system or an inkjet system. 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 4 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 4 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 4 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, in the copier mode, it is possible to display on the image display device 4 image data converted into a color similar to that of the original after reading the original.

  Further, in the image forming apparatus 100, in the copier mode or the facsimile reception mode, it is possible to display, on the image display apparatus 4, the image data converted into a color close to the actual printed matter before printing is performed. It has become. Further, the image forming apparatus 100 can display a preview of an image to be transmitted on the image display device 4 before execution of transmission in the facsimile transmission mode or the image transmission mode.

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

  The image display device 4 is not limited to a liquid crystal display, and may be display means other than the liquid crystal display (for example, an organic EL display, a plasma display, etc.).

  The storage device 5 is a memory or a hard disk for temporarily storing image data handled by the image processing device 1.

  The receiving device 6 is connected to a telephone line or the Internet, and receives image data from an external device by facsimile communication. The transmission device 7 is connected to a telephone line or the Internet, and is a device that transmits image data input by the image input device 2 to an external device by facsimile communication.

  The control unit 8 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. The control unit 8 also has a function of controlling data transfer between the respective hardware provided in the image forming apparatus 100.

  Next, details of processing executed in each block of the image processing apparatus 1 in the copier mode will be described in detail. The image processing apparatus 1 according to the present embodiment includes 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 1 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 1 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 1 will be described for the copier mode, and will be described separately for printing processing and image data display.

(1) Copier mode print processing (image print job)
Below, the image processing apparatus 1 is demonstrated based on FIG. FIG. 6 shows the flow of image data in the image processing apparatus 1 when printing processing is performed in the copier mode and the full color mode.

  The A / D (analog / digital) converter 21 is a block that converts a color image signal (RGB analog signal) sent from the image input apparatus 2 into digital image data (RGB digital signal). The shading correction unit 22 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 apparatus 2 on the image data sent from the A / D conversion unit 21. . The input processing unit 23 is a block that performs gradation conversion processing (input processing) such as γ correction processing on each of the RGB image data sent from the shading correction unit 22.

  The document type automatic determination unit 24 determines the type of document read by the image input device 2 based on RGB image data (RGB density signal) that has been subjected to processing such as γ correction by the input processing unit 23. 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 24 performs automatic color determination (ACS), which is a process for determining whether the 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 discrimination unit 24 is input to the region separation processing unit 25 and the compression unit 26.

  Based on the RGB image data sent from the document type automatic discrimination unit 24, the region separation processing unit 25 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 25 include a black character region, a color character region, a halftone dot region, and the like. Note that the region separation processing unit 25 may be configured not to determine the image region for each pixel but to determine the image region for each block including a plurality of pixels.

  The compression unit 26 is a block that performs processing for encoding the image data (RGB signals) sent from the document type automatic discrimination unit 24. Note that the encoding is performed based on, for example, a JPEG (Joint Photographic Experts Group) system.

  The region separation signal compression unit 27 is a block that performs compression processing on the region separation signal generated for each pixel. The compression processing in the region separation signal compression unit 27 is performed based on, for example, an MMR (Modified Modified Reed) method and an MR (Modified Reed) method, which are lossless compression methods.

  The control unit 8 temporarily stores the encoded code (encoded image data) output from the compression unit 26 and the region separation signal code (compressed region separation signal) output from the region separation signal compression unit 27. It is stored in the device 5 and managed as filing data. When the copy output operation is instructed, the control unit 8 reads the encoded code and the region separation signal code corresponding to the encoded code from the storage device 5, and performs the decoding unit 28 and the region separation signal decoding unit 29. To each.

  The control unit 8 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 8 controls reading or writing of the encoded code and the region separation signal code using the management table.

  The decoding unit 28 performs a decoding process on the encoded code to expand the encoded code into RGB image data. The region separation signal decoding unit 29 performs a decoding process on the region separation signal code. The decoded region separation signal is delivered to the black generation / undercolor removal unit 32, the spatial filter unit 33, and the halftone generation unit 36. In the black generation / undercolor removal unit 32, the spatial filter unit 33, and the halftone generation unit 36, the image processing content is switched according to the type of the image area.

  The image quality adjustment unit 30 detects the background of the RGB image data sent from the decoding unit 28 and performs background removal correction. Further, the image quality adjustment unit 30 adjusts 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 30 performs a process of converting 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 Expression 2. Note that the coefficients r1 to r3 in Expression 2 are determined based on Table 1 below. For example, when the user selects cyan as a desired color in the single color mode, the values of r1 to r3 belonging to the column “Cyan” in Table 1 below are referred to, and r1 = 1, r2 = 0, r3 = 0 will be selected.

  In other words, the output from the image quality adjustment unit 30 in the full color mode is RGB image data as shown in FIG. 6, and the output from the image quality adjustment unit 30 when the single color mode is selected is as follows. As shown in FIG. 7A, the image data is CMY. Note that the output from the image quality adjustment unit 30 when the two-color mode is selected is RGB image data as shown in FIG. FIG. 7A shows a part of the blocks of the image processing apparatus 1 when the printing process is performed in the copier mode and the single color mode. FIG. 7B shows a part of blocks of the image processing apparatus 1 when the printing process is performed in the copier mode and the two-color mode.

  Further, the vividness adjustment executed by the image quality adjustment unit 30 can be realized by changing each value of r1 to r3 and a1 to a3 of the matrix of the formula 2 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 above vividness adjustment and the image data conversion process in the single color mode are performed by the same processing unit (image quality adjustment unit 30).

  When the two-color mode is selected, the two-color processing unit 31 converts the RGB image data output from the image quality adjustment unit 30 into CMY image data as shown in FIG. 7B. It is a block that performs. In the two-color mode, RGB image data is converted into CMY image data based on the method described above.

  Further, when the full color mode is selected, the two-color processing unit 31 does not perform any processing on the RGB image data output from the image quality adjustment unit 30, as shown in FIG. The image data is transferred to the second color correction unit 14 as it is (through). Further, when the single color mode is selected, the two-color processing unit 31 performs no processing on the CMY image data output from the image quality adjustment unit 30 as illustrated in FIG. First, the image data is transferred to the second color correction unit 14 as it is (through).

  When the full color mode is selected, the second color correction unit 14 performs color correction processing for converting RGB image data output from the two-color processing unit 31 into CMY image data, as shown in FIG. And a block having a function as a color correction processing unit that performs processing for improving the color reproducibility on the image data. 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. . In other words, in the present embodiment, the second color correction unit 14 that performs the above-described second color correction processing is also used as a color correction processing unit that performs color correction on the image data supplied to the image output device 3.

  In addition, when the single color mode or the two-color mode is selected, the second color correction unit 14 is output from the two-color processing unit 31 as shown in FIGS. 7A and 7B. No processing is performed on the CMY image data, and the image data is transferred to the black generation / undercolor removal unit 32 as it is (through).

  The black generation / under color removal unit 32 generates black (K) image data from the CMY image data output from the second color correction unit 14 when the full color mode or the two-color mode is selected. On the other hand, it is a block that performs processing for generating new CMY image data by subtracting black (K) image data from original CMY image data. Accordingly, 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 / undercolor removal unit 32 as shown in FIGS. 6 and 7B. Converted to image data.

  Further, when the single color mode is selected, the black generation / under color removal unit 32 applies to the CMY image data output from the second color correction unit 14 as illustrated in FIG. No processing is performed, and the image data is handed over to the subsequent spatial filter unit 33 (through).

  When the full color mode or the two-color mode is selected, the output of the black generation / under color removal unit 32 and the input / output of each block subsequent to the black generation / under color removal unit 32 are shown in FIG. Thus, the image data is CMYK. However, when the single color mode is selected, as shown in FIG. 7A, the output of the black generation / under color removal unit 32 and each block subsequent to the black generation / under color removal unit 32 Unlike the case of FIG. 6, the input / output of CMY is CMY image data.

  The spatial filter unit 33 applies spatial filter processing (enhancement processing, smoothing) to the CMYK or CMY image data output from the black generation / undercolor removal unit 32 based on a region separation signal (region identification signal). Process). That is, the spatial filter unit 33 executes different image processing for each image region based on the region separation signal.

  The scaling unit 34 is a block that performs image enlargement or reduction processing based on a scaling command (information indicating the magnification of the print image) input by the user via an operation panel (not shown).

  The output tone correction unit 35 is a block that performs output γ correction processing for outputting the image data output from the scaling unit 34 to a recording medium such as paper. The halftone generation unit 36 performs tone reproduction processing (halftone generation processing) necessary for printing an image in the image output apparatus 3 using an error diffusion method or a dither method.

  The CMYK or CMY image data output from the halftone generation unit 36 is transferred to the image output device 3, and the image output device 3 prints an image of the image data on a recording medium (for example, paper). .

(2) Image data display in copier mode Next, in the copier mode, when image data obtained by reading a document is converted to a color similar to that of the document and displayed, and color similar to output (printing) The contents of the processing executed in each block of the image processing apparatus 1 in the case of converting the image to be displayed as an output preview will be described with reference to FIG. FIG. 8 is a block diagram showing the same image forming apparatus 100 as the image forming apparatus 100 of FIG. 6, and shows the flow of image data when performing image display in the copier mode and the full color mode.

  An A / D (analog / digital) conversion unit 21, a shading correction unit 22, an input processing unit 23, a document type automatic discrimination unit 24, a region separation processing unit 25, a compression unit 26, a region separation signal compression unit 27, and a decoding unit. 28, the image quality adjustment unit 30, and the two-color processing unit 31 are the same as those in the printing process in the copier mode described above.

  RGB image data from the document type automatic discrimination unit 24 is input to the first color correction unit 11. The input image data is data conforming to the color space of the image input device (scanner) 2. Then, the first color correction unit 11 performs a process of converting the RGB value of the input image data into an RGB value having a color similar to that of the original, and passes it to the gamma correction unit 12.

  The gamma correction unit 12 performs gamma correction on the RGB values of the image data in accordance with the characteristics of the image display device 4 and passes them to the resolution conversion unit 13.

  The resolution conversion unit 13 performs a process of reducing the resolution of the image data in order to reduce the size of the image data and speed up the image display. As shown in FIG. 8, the image data whose resolution has been lowered by the resolution conversion unit 13 is sent to the image display device 4 and displayed as an image having a color similar to that of the original (original reference image).

  In this way, the processing is performed so that the color of the document reference image displayed on the image display device 4 is close to the color of the document image read by the image input device 2, that is, the difference between these colors is reduced. can do. For this reason, the user can confirm with accuracy on the image display device 4 that the original read by the image input device 2 is correct. The color correction processing in the first color correction unit 11 is based on the color reproduction characteristics of the image input device and the color specification reproduction characteristics of the image display device, that is, processing based on the color reproduction characteristics of the image output device 3. Therefore, the document reference image having a color close to the color of the document image can be displayed on the image display device 4 in a short time.

  The image data whose resolution has been lowered by the resolution conversion unit 13 is also sent to the compression unit 26.

  When an image (output reference image) is displayed as an output (print) preview, the region separation signal decoding unit 29, as shown in FIG. 8, uses the decoded region separation signal as a spatial filter unit 33 and an output tone correction unit. Hand over to 35.

  In the full color mode, RGB image data is input to the second color correction unit 14. Then, the second color correction unit 14 converts the RGB value of the image data into an R′G′B ′ value having a color close to that of the output (printed) product. This conversion process is realized by creating an LUT in which an input RGB value and an output R′G′B ′ value are associated with each other, and looking up an output value from the created LUT.

  In the present embodiment, in the full color mode, the image processing circuit is shared for the conversion processing from RGB image data to CMYK image data during printing processing and the color conversion processing of RGB image data during image data display. doing.

  Here, FIG. 8 shows the image forming apparatus 100 when the full color mode is selected, as in FIG. 6, and the second color correction unit 14 receives RGB image data in the full color mode. It has come to be. However, in the single color mode or the two-color mode, as shown in FIGS. 9A and 9B, the second color correction unit 14 receives CMY image data. FIG. 9A shows a part of blocks of the image processing apparatus 1 when output preview display processing is performed in the copier mode and the single color mode. FIG. 9B shows a part of the blocks of the image processing apparatus 1 when output preview display processing is performed in the copier mode and the two-color mode.

  In the single color mode or the two-color mode, the second color correction unit 14 performs a process of converting the input CMY image data into R′G′B ′ image data. That is, a process of converting CMY image data suitable for the printing characteristics of the second color correction unit 14 print processing into R′G′B ′ image data having a color close to the output product is performed. The process of converting the CMY image data into the R′G′B ′ image data also creates an LUT in which the input CMY value and the output R′G′B ′ value are associated with each other. This is realized by looking up the output value.

  As shown in FIGS. 8, 9A, and 9B, the black generation / undercolor removal unit 32 is the second color in any of the single color mode, the two color mode, and the full color mode. No processing is performed on the R′G′B ′ image data output from the correction unit 14, and the image data is directly passed to the subsequent spatial filter unit 33 (through).

  The spatial filter unit 33 applies spatial filter processing (enhancement processing, smoothing processing) to the R′G′B ′ image data output from the black generation / undercolor removal unit 32 using a digital filter based on the region separation signal. Etc.). That is, in the spatial filter unit 33, different image processing is executed for each image region based on the region separation signal as in the printing processing.

  The scaling unit 34 does not perform any processing on the R′G′B ′ image data output from the spatial filter unit 33, and passes the image data as it is to the output tone correction unit 35 in the subsequent stage ( Through). Since FIG. 8 shows a case where there is a scan-in instruction input and the image is displayed on the image display device 4 after being converted to a color similar to the original, the data passed to the second color correction unit 14 is This is the data that has been thinned out by the resolution conversion unit 13. Therefore, it is not necessary to perform the thinning process in the zoom unit 34, and the zoom unit 34 passes through.

  The output tone correction unit 35 performs output γ correction processing on the image data output from the scaling unit 34 based on the region separation signal. More specifically, the output tone correction unit 35 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 4 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. 10A is a gamma curve corresponding to the display characteristics of the image display device 4. Also, the curve indicated by the solid line in FIG. 10B is a gamma curve for clearly displaying characters. The broken line in FIG. 10B is a gamma curve corresponding to the display characteristics of the image display device 4 and is shown for comparison with a gamma curve for clearly displaying characters.

  In the present embodiment, the output tone correction unit 35 selects a gamma curve based on the region separation signal, but does not perform selection based on the region separation signal, and only the gamma curve of FIG. It may be used to perform output gradation correction.

  Then, the halftone generation unit 36 does not perform any processing on the R′G′B ′ image data output from the output tone correction unit 35, and uses the image data as it is to the subsequent image display device 4. Deliver (through). Accordingly, the image display device 4 can display an output reference image that is a preview of output (printing) based on the image data of R′G′B ′.

  Thus, the color of the output reference image displayed on the image display device 4 is close to the color of the image printed on the image output device 3, that is, the difference between these colors is reduced. Therefore, an output reference image having a color close to the print output in the image output device 3 is displayed. Therefore, the user can accurately check the output image before copying (printing).

  Note that the output γ correction processing executed in the output tone correction unit 35 may be executed in the halftone generation unit 36.

  The processing for displaying the original reference image converted to a color close to the original when the copier mode is selected and the processing for displaying the output reference image converted to a color close to output (printing) are described above. did. In addition to the above, for example, when the fax transmission mode or the image transmission mode is selected, that is, when reading a document, a process of displaying a document reference image converted to a color close to the document is performed. Also good.

In addition, when the image transmission mode is selected, a process of displaying an output reference image converted to a color close to the output in image transmission may be performed. In this case, for example, the monitor is limited to a sRGB color space monitor that is widely used in general, and the correspondence between RGB values and L ^* a ^* b ^* values in the sRGB color space, and R′G ′ in the image display device 4. Based on the correspondence between the B 'value and the L ^* ' a ^* 'b ^* ' value, an LUT that associates the RGB value with the R'G'B 'value is created to monitor the image to be transmitted in the sRGB color space. The image display device 4 can realize the color when viewed in the above.

  In the fax reception mode or the print mode (when the document is not read), a process for displaying the output reference image converted to a color close to output (printing) may be performed.

(3) Process Flow in Copier Mode Next, an example of the process flow when the copier mode and the full color mode are selected will be described with reference to FIG. FIG. 11 is a flowchart illustrating an example of a processing procedure of the image forming apparatus 100 when the copier mode and the full color mode are selected.

  First, the image forming apparatus 100 determines whether the copier mode is selected and the scan-in key is pressed (scan-in instruction is input) (S21). When the scan-in key is pressed, S22 to S31 are executed, and when the scan-in key is not pressed, S32 to S37 are executed. Hereinafter, S22 to S31 will be described first, and then S32 to S37 will be described.

  When the scan-in key is pressed (YES at S21), the original is scanned (S22) to generate RGB analog signals. It is assumed that the user has set the presence or absence of the preview display for the image forming apparatus 100 by inputting the setting information indicating whether or not the preview display is necessary before pressing the scan-in key in S21.

  After S22, the image forming apparatus 100 converts RGB analog signals into RGB image data (digital signals) (S23), performs shading correction on the image data (S24), and performs RGB after shading correction. Input processing such as input γ correction processing is performed on the image data (S25).

  After S25, the image forming apparatus 100 performs document type determination processing and region separation processing based on the RGB image data (S26). Since the scan-in key is pressed in S21, the first color correction processing (S27) is performed. ), Gamma correction processing (S28), and resolution conversion processing (S29) are performed to form image data having a color similar to that of the original. Then, a color image (original reference image) close to the original is displayed (S30). Further, the image data is stored in the storage device 5 (S31).

  If the scan-in key is not pressed in S21 (NO in S21), it is determined whether the start key is pressed (start instruction is input) (S32). If the start key is not pressed (NO in S32), the process returns to S21. When the start key is pressed (YES in S32), an analog signal of RGB is generated by scanning the document (S33) as in S22.

  After S33, the image forming apparatus 100 converts RGB analog signals to RGB image data (digital signals), similarly to S23 to S25 (S34), and performs shading correction on the image data (S35). Then, input processing such as input γ correction processing is performed on the RGB image data after shading correction (S36). After S36, the image forming apparatus 100 performs the document type determination process and the area separation process based on the RGB image data as in S26 (S37). Then, the image data is stored in the storage device 5 (S31).

  After S31, the image forming apparatus 100 determines whether preview display is set (whether an instruction is input) (S38). If the preview display is not set (S38). NO), S39 to S46 are executed, and if the setting for preview display is made (YES in S38), S47 to S53 are executed. Hereinafter, S39 to S46 will be described first, and then S47 to S53 will be described.

  If it is determined in S38 that the setting for preview display has not been made (NO in S38), the image forming apparatus 100 reads RGB image data from the storage device 5, and performs background removal correction, vividness adjustment, and the like. Image quality adjustment processing is performed (S39). Thereafter, the image forming apparatus 100 converts RGB image data corresponding to the characteristics of the image input device (scanner) 2 into CMY image data corresponding to the characteristics of the image output device (printer) 3 (S40), and further , CMY image data is converted into CMYK image data (S41).

  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 (S42), and performs a scaling process on the CMYK image data after the spatial filter process (S42). S43). After S43, the image forming apparatus 100 performs output γ correction (output gradation correction) processing (S44) and gradation reproduction processing on the CMYK image data (S45), and prints the image of the image data on paper. (S46), and the process ends.

  If it is determined in S38 that the preview display is set (YES in S38), the image forming apparatus 100 reads the RGB image data from the storage device 5 and performs the same image quality adjustment process as the image quality adjustment process in S39. (S47). Thereafter, the image forming apparatus 100 converts RGB image data corresponding to the characteristics of the image input device (scanner) 2 into R′G′B ′ image data corresponding to the characteristics of the image display device 4 (S48). . After S18, the image forming apparatus 100 performs a spatial filter process on the image data of R'G'B 'based on the result of the region separation process (S49). If there is no scan-in instruction input in S21, the R'G'B so that the image data of R'G'B 'matches the display resolution and size of the image display device 4. The thinning process is performed on the image data of '(S50). This is because when the scan-in is not performed, the resolution conversion unit 13 does not perform processing (does not pass through the resolution conversion unit 13), and thus the scaling unit 34 needs to perform thinning processing. is there. When the scan-in is performed, since the processing in the resolution conversion unit 13 is performed, S50 is skipped and the process proceeds to S51 after S49.

  Thereafter, the image forming apparatus 100 performs output γ correction (output gradation correction) processing on the image data of R′G′B ′ based on the result of the region separation processing (S51). After S51, the image forming apparatus 100 displays an output reference image (output preview display) based on the image data of R'G'B '(S52). This output reference image is a color image used for an output (print).

  After S52, when a command indicating print permission is input from the user (YES in S53), image forming apparatus 100 reads again the RGB image data stored in storage device 5, and this image data Based on the above, the processes of S39 to S46 are executed to perform printing. On the other hand, after S52, if a command indicating print cancellation is input from the user or a command indicating print permission is not input from the user (NO in S53), image forming apparatus 100 ends the process.

(1-4) Modification In the image forming apparatus 100 shown in FIG. 6, the compressed image data (encoded code) and the region separation signal code are stored in the storage device 5 in association with each other. However, like the image forming apparatus 100a shown in FIG. 12, after the image input device 2 reads the document and obtains the image data, the read image data is encoded before the region separation process and the document type determination process. The image data may be temporarily stored in the storage device 5 and read out from the storage device 5 and decoded, and the document type determination process and the area separation process may be performed.

  Further, the image forming apparatus 100 shown in FIG. 6 and the image forming apparatus 100a shown in FIG. 12 are in the image filing mode (when the job such as the copier mode, the print mode, the facsimile transmission mode, the facsimile reception mode, and the image transmission mode is selected. Image filing job) may be executable. This image filing mode refers to creating an image file (JPEG, TIFF file, etc.) based on image data obtained by the image input device 2 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 5.

  Here, at the time of filing in the image filing mode, the image data obtained by the image input device 2 or image data received from the outside is converted into an image file (JPEG, TIFF file, etc.) by the image processing device 1, and thereafter The file is sent to a filing processing unit (job device) (not shown), and the filing processing unit stores the image file in the storage device 5.

  Also, when previewing while selecting each job (copier mode, print mode, facsimile transmission mode, etc.), the image data obtained by the image input device 2 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 1 and then sent to the image display apparatus 4. Further, when the preview is performed during selection of each job, the content of the image processing executed by the image processing apparatus 1 is the same regardless of whether or not the image filing mode is executed. For example, the processing contents of the image processing apparatus 1 are shown in FIG. 8 and FIG. 9 (in FIG. 8 and FIG. 9) regardless of whether or not the image filing mode is executed. The processing is as shown in a) and (b).

  The description of each process in the print mode, facsimile transmission mode, facsimile reception mode, and image transmission mode in the image forming apparatus 100 is omitted. As described above, even in these modes, when reading an original, the process of converting to a color close to the original and displaying it, and the color converted to a color close to output (image transmission) are output. The process of displaying as a preview of the image may be performed.

(Program / Recording medium)
The image processing apparatus 1 of the present embodiment may be configured by hardware logic, or may be realized by software using a CPU as follows.

  That is, the image processing apparatus 1 includes a CPU (central processing unit) that executes instructions of a control program that realizes each function, a ROM (read only memory) that stores the program, and a RAM (random access memory) that expands the program. And a storage device (recording medium) such as a memory for storing the program and various data. An object of the present invention is a recording medium in which program codes (execution format program, intermediate code program, source program) of a program that performs filter coefficient synthesis processing, which is software that realizes the functions described above, are recorded so as to be readable by a computer. Can also be achieved by reading the program code recorded in the recording medium and executing it by the computer (or CPU or MPU).

  Examples of the recording medium include a tape system such as a magnetic tape and a cassette tape, a magnetic disk such as a floppy (registered trademark) disk / hard disk, and an optical disk such as a CD-ROM / MO / MD / DVD / CD-R. Card system such as IC card, IC card (including memory card) / optical card, or semiconductor memory system such as mask ROM / EPROM / EEPROM / flash ROM.

  Further, the image processing apparatus 1 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Further, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth ( (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. 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 present invention is not limited to the above-described embodiments, and various modifications are possible. The technology of the present invention is also applied to embodiments obtained by appropriately combining the respective technical means disclosed in the above-described embodiments. Included in the scope.

  The image processing apparatus of the present invention can be used for an apparatus that can display a preview for handling image data, and is particularly suitable for a multifunction machine, a copier, and a facsimile.

DESCRIPTION OF SYMBOLS 1 Image processing device 2 Image input device 3 Image output device 4 Image display device 5 Storage device 6 Receiving device 7 Transmitting device 8 Control unit 11 First color correction unit 12 Gamma correction unit 13 Resolution conversion unit 14 Second color correction unit

Claims (10)

An image processing apparatus that supplies image data to an image display device when the image input device performs image processing on image data obtained by reading a document image and outputs the image data from the image output device;
A first color correction unit that performs a first color correction process on the image data supplied to the image display device based on the color reproduction characteristics of the image input device and the color specification reproduction characteristics of the image display device;
Second color correction for performing second color correction processing on the image data subjected to the first color correction processing based on the color reproduction characteristics of the image output device and the color reproduction characteristics of the image display device With
The first color correction unit receives a first instruction input indicating whether or not an operation is necessary, determines whether or not to execute the first color correction process according to the first instruction input,
The second color correction unit receives a second instruction input indicating whether or not an operation is necessary, and determines whether or not to execute the second color correction process according to the second instruction input;
Based on the presence or absence of the first instruction input and the second input instruction, the first color correction processing is image data subjected, and, above the second color correction processing the image data subjected to said image display the image processing apparatus characterized by controlling the supply to the device.   The first instruction input is an instruction input for sequentially reading a document from the image input device,
  The image processing apparatus according to claim 1, wherein the second instruction input is an instruction input for performing a preview display of the image data on the image display apparatus. When the first instruction input and the second instruction input are not made, the first color correction unit and the second color correction unit do not execute the first color correction process and the second color correction process, respectively, The image processing apparatus according to claim 1, wherein image processing is performed in accordance with output from the image output apparatus. The image output apparatus, an image processing apparatus according to any one of claims 1 3, characterized in that the printing apparatus for performing image printing. The first color correction section, the matrix operation, the image processing apparatus according to any one of 4 from claim 1, wherein applying the first color correction processing. The image processing apparatus according to claim 4 , wherein the second color correction unit is also used as a color correction processing unit that performs color correction on image data supplied to the printing apparatus. Comprising an image processing apparatus according to any one of claims 1 to 6, an image input device for reading an original image, an image output device that outputs the image data, an image display device for displaying an image data, the An image forming apparatus. An image processing method for supplying image data to an image display device when the image input device performs image processing on image data obtained by reading a document image and outputs the image data by an image output device,
A first color correction step of applying a first color correction process to the image data supplied to the image display device based on the color reproduction characteristics of the image input device and the color specification reproduction characteristics of the image display device;
Second color correction for performing second color correction processing on the image data subjected to the first color correction processing based on the color reproduction characteristics of the image output device and the color reproduction characteristics of the image display device Including steps,
The first color correction step determines whether or not to execute the first color correction process according to the first instruction input according to the first instruction input indicating whether or not the operation is necessary,
The second color correction step determines whether or not to execute the second color correction process according to the second instruction input according to the second instruction input indicating whether or not the operation is necessary,
Based on the presence or absence of the first instruction input and the second input instruction, the first color correction processing is image data subjected, and, above the second color correction processing the image data subjected to said image display An image processing method comprising controlling supply to an apparatus. An image processing program for operating an image processing apparatus according to any one of claims 1 to 6, an image processing program for causing a computer to function as the above sections of the image processing apparatus. A computer-readable recording medium on which the image processing program according to claim 9 is recorded.

Images