JP6241048B2 - Image forming apparatus, image forming method, and image forming program - Google Patents

Description

  The present invention relates to an image forming apparatus, an image forming method, and an image forming program.

  Conventionally, it is provided with four color toners used for reproducing the color (gradation) of an image, and a transparent toner used for embedding predetermined additional information in an image and for adding gloss to an image. An image forming apparatus is known (for example, see Patent Document 1). In such a conventional image forming apparatus, it is desired to reduce the total usage amount of toner (the total usage amount of color toner and transparent toner).

  However, in the conventional image forming apparatus as described above, when reducing the total amount of toner used, the transparent toner is preferentially secured regardless of the use of the transparent toner for the purpose of reliably embedding additional information. In addition, the amount of color toner used was preferentially reduced. For this reason, even when there is no need to prioritize securing transparent toner (for example, when transparent toner is used for applying gloss to an image), priority is given to reducing the amount of color toner used. In some cases, the tone reproducibility could not be sufficiently ensured.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to appropriately reduce the total amount of toner used while ensuring the reproducibility of image gradation. An image forming apparatus, an image forming method, and an image forming program are provided.

In order to achieve the above object, an image forming apparatus according to the present invention includes a first determination unit that determines a usage amount of a first toner mainly used for reproducing gradation of an image formed on a sheet, and a first determination unit. When the second determination unit that determines the usage amount of the second toner that is mainly used for an application different from the toner, the reception unit that receives setting of the operation mode by the user, and the first operation mode is set as the operation mode, The sum of the usage amounts of the first toner and the second toner respectively determined by the 1 determination unit and the second determination unit is reduced to the first threshold value or less by a reduction method according to the use of the second toner, and the operation mode is set. When the second operation mode is set to further reduce the sum of the usage amounts of the first toner and the second toner than the first operation mode, the sum of the usage amounts of the first toner and the second toner is calculated. In reduction method corresponding to the second toner applications, and a reduction unit for reducing the following smaller than the first threshold second threshold.

  According to the present invention, the total amount of toner can be appropriately reduced while ensuring the reproducibility of the gradation of the image by configuring as described above.

FIG. 1 is a block diagram showing a schematic configuration of the printer apparatus according to the first embodiment. FIG. 2 is a block diagram illustrating a detailed configuration of the image processing unit of the printer apparatus according to the first embodiment. FIG. 3 is a flowchart for explaining the operation of the special toner image generation unit of the image processing unit shown in FIG. FIG. 4 is a table for explaining the operation of the special toner image generation unit of the image processing unit shown in FIG. FIG. 5 is a diagram for explaining details of a method for reducing the total amount of color toner and clear toner used in the printer apparatus according to the first embodiment. FIG. 6 is a diagram for explaining details of a method for reducing the total amount of color toner and clear toner used in the printer apparatus according to the first embodiment. FIG. 7 is a diagram for explaining the relationship between the usage amount of the clear toner and the recognition rate of the embedded information when the clear toner is used for applying embedded information to an image. FIG. 8 is a diagram for explaining details of a method for reducing the total amount of color toner and clear toner used in the printer apparatus according to the first embodiment. FIG. 9 is a diagram for explaining details of a method for reducing the total amount of color toner and clear toner used in the printer apparatus according to the first embodiment. FIG. 10A is a diagram illustrating an example of output data from the color space conversion unit of the image processing unit illustrated in FIG. 2. 10B is a diagram illustrating an example of output data from the black processing unit of the image processing unit illustrated in FIG. FIG. 10C is a diagram illustrating an example of output data from the total amount regulating unit of the image processing unit illustrated in FIG. FIG. 11A is a diagram illustrating an example of output data from the color space conversion unit of the image processing unit illustrated in FIG. 2. FIG. 11B is a diagram illustrating an example of output data from the black processing unit of the image processing unit illustrated in FIG. FIG. 11C is a diagram illustrating an example of output data from the total amount regulating unit of the image processing unit illustrated in FIG. FIG. 12 is a diagram for explaining the details of the reduction method of the total usage amount of the clear toner and the color toner in the printer device according to the second embodiment. FIG. 13 is a diagram for explaining the details of the reduction method of the total usage amount of the clear toner and the color toner in the printer device according to the second embodiment. FIG. 14 is a diagram for explaining the details of the reduction method of the total usage amount of the clear toner and the color toner in the printer device according to the second embodiment. FIG. 15 is a diagram for explaining the details of the reduction method of the total usage amount of the clear toner and the color toner in the printer device according to the third embodiment.

  Hereinafter, embodiments will be described with reference to the drawings. In addition, the specific numerical value described below is an example to the last, and is not limited to this.

(First embodiment)
First, the configuration of the printer apparatus 100 according to the first embodiment will be described with reference to FIGS. 1 and 2. The printer apparatus 100 is an example of an “image forming apparatus”.

  As shown in FIG. 1, the printer apparatus 100 includes a CPU (Central Processing Unit) 1, an NVRAM (Non Volatile Random Access Memory) 2, a ROM (Read Only Memory) 3, and a RAM 4. In addition, the printer device 100 includes an engine unit 5, an engine I / F (interface) 6, a display panel unit 7, a panel I / F 8, an embedded information generation unit 9, a storage disk unit 10, a disk I / F. F11, host I / F12, and image processing unit 13 are provided.

  The CPU 1 controls each unit of the printer apparatus 100 based on a control program stored in the ROM 3, a user operation on the display panel unit 7, a control command from a host computer 500 (described later) connected to the host I / F 12, and the like. Configured to control. The NVRAM 2 is a non-volatile RAM that stores data such as the contents of operation of the display panel unit 7 by the user. The RAM 4 is used as a work memory for the CPU 1, a buffer for input data, a page buffer for print data, a memory for download fonts, and the like.

  Further, the engine unit 5 includes a color toner 5a corresponding to a process color including four colors of cyan (C), magenta (M), yellow (Y), and black (K), and a clear and clear recording agent. This is a mechanism for printing an image on a sheet or the like using the toner 5b. The color toner 5a is mainly used for the purpose of reproducing the gradation of an image. The clear toner 5b is mainly used for the purpose of giving predetermined embedding information (details will be described later) to the image and the purpose of giving gloss to the image. The color toner 5a is an example of “first toner” and “colored toner”. The clear toner 5b is an example of “second toner” and “spot color toner”. The engine I / F 6 functions as a communication interface between the engine unit 5 and each unit other than the engine unit 5 of the printer apparatus 100.

  The display panel unit 7 is a touch panel type input / output unit, and is used for displaying the status of the printer apparatus 100 and inputting a user's mode selection instruction. For example, in the first embodiment, the printer apparatus 100 has two modes of a normal operation mode (see FIGS. 5 and 6 described later) and a toner consumption reduction mode (see FIGS. 7 to 9 described later). The user can select and specify the two modes by operating the display panel unit 7. This user operation result is stored in the NVRAM 2. The panel I / F 8 functions as a communication interface between the display panel unit 7 and each unit other than the display panel unit 7 of the printer apparatus 100.

  In the first embodiment, the user can select the embedded information addition mode by operating the display panel unit 7. Specifically, the user operates the display panel unit 7 to display whether or not the copy-forgery-inhibited copy-forgery-inhibited pattern data is embedded in the image data and whether or not the document to be printed is an original. It is possible to select / designate whether or not to embed data in image data. Here, when the embedded information addition mode is selected / designated by the user, the embedded information generating unit 9 is configured to generate predetermined pattern information corresponding to the mode and generate X data described later. ing. In the first embodiment, the user can set the glossiness designation mode for designating the glossiness of the output image by operating the display panel unit 7.

  The storage disk unit 10 is a storage unit (for example, a hard disk) for storing font data, programs, print data, and the like. The disk I / F 11 functions as a communication interface between the storage disk unit 10 and each unit other than the storage disk unit 10 of the printer device 100. The host I / F 12 is connected to a host computer 500 (for example, PC: Personal Computer) that outputs RGB image data. The host I / F 12 functions as a communication interface between the host computer 500 and the printer apparatus 100. The RGB image data output from the host computer 500 to the printer device 100 is divided into three types of objects, text, graphics, and images, and has a data format that can be interpreted by the printer device 100.

  Based on the RGB image data input from the host computer 500 and the X data corresponding to the pattern information generated by the embedded information generating unit 9, the image processing unit 13 performs each color (cyan) of the color toner 5a of the engine unit 5. , Magenta, yellow and black), pseudo halftone processed image data comprising C signal, M signal, Y signal and K signal respectively corresponding to the color (transparent) of the clear toner 5b of the engine unit 5 Is configured to output. The X data is data having the same number of pixels as RGB data in both main scanning and sub scanning, and 1-bit data indicating which pixel is embedded with a pattern representing embedding information, and image data is text, This is 3-bit data in total consisting of 2-bit data indicating whether it corresponds to a graphic or an image.

  As shown in FIG. 2, the image processing unit 13 includes a color conversion processing unit 14, a special toner image generation unit 15, a total amount regulation unit 16, and a halftone processing unit 17. The color conversion processing unit 14, the special toner image generation unit 15, and the total amount regulation unit 16 are examples of a “first determination unit”, a “second determination unit”, and a “reduction unit”, respectively. The color conversion processing unit 14 includes a color space conversion unit 14a and a black processing unit 14b.

  The color space conversion unit 14a has a function of converting image data corresponding to the RGB color space. For example, the color space conversion unit 14a converts image data corresponding to the RGB color space into image data corresponding to a color space expressed by C ′ (cyan), M ′ (magenta), and Y ′ (yellow). Or can be converted into a grayscale image using luminance information.

  The black processing unit 14b performs a process (black processing) for generating a K (black) signal in accordance with an output signal (C′M′Y ′ signal) from the color space conversion unit 14a, and C′M ′. Under color removal processing (UCR: Under Color Removal processing) for removing a portion corresponding to the K signal from the Y ′ signal is performed. Here, the signal output from the black processing unit 14 b corresponds to each color (C, M, Y, and K) of the color toner 5 a of the engine unit 5. That is, the value of the sum (CMYK signal) of the signals output from the black processing unit 14 b corresponds to the usage amount of the color toner 5 a of the engine unit 5.

  The special toner image generation unit 15 is configured to generate transparent image data (T signal) based on the CMYK signal output from the black processing unit 14b and the X data. The value of the T signal output from the special toner image generation unit 15 corresponds to the usage amount of the clear toner 5b of the engine unit 5.

  Here, in the first embodiment, the total amount regulation unit 16 regulates the total sum of the CMYK signal value and the T signal value output from the special toner image generation unit 15 so as not to exceed a predetermined upper limit value. Thus, the color conversion processing unit 14 (black processing unit 14b) and the special toner image generation unit 15 have a function of reducing the sum of the usage amounts of the color toner 5a and the clear toner 5b, respectively. The total amount regulating unit 16 is provided to prevent an excessive load from being applied to the process and to prevent a fixing failure.

  Specifically, the total amount regulating unit 16 sets the total usage amount of the color toner 5a and the clear toner 5b in accordance with the use of the clear toner 5b in the normal operation mode in which the toner consumption reduction mode is not set. The reduction method is configured to reduce to a predetermined threshold value (first threshold value) or less. Specifically, the total amount regulating unit 16 switches the reduction method according to whether or not the clear toner 5b is used for giving predetermined embedding information to the image, thereby using the usage amount of the color toner 5a and the clear toner 5b. Is configured to reduce the sum of

  For example, when the clear toner 5b is used for the purpose of adding embedded information to an image, the total amount regulating unit 16 preferentially reduces the amount of color toner 5a used (see FIGS. 5 and 5 described later). 6), the total usage amount of the color toner 5a and the clear toner 5b is reduced. Further, when the clear toner 5b is not used for applying embedded information to an image (when used for applying gloss to an image), the total amount regulating unit 16 preferentially uses the amount of the clear toner 5b used. The second reduction method (see FIGS. 7 to 9 described later) reduces the total amount of color toner 5a and clear toner 5b used.

  Further, the total amount regulating unit 16 is configured to be able to reduce the total sum of the usage amounts of the color toner 5a and the clear toner 5b to a second threshold value that is smaller than the first threshold value, according to a user setting. Has been. That is, the total amount regulating unit 16 is configured to reduce the sum of the usage amounts of the color toner 5a and the clear toner 5b to a second threshold value or less when the toner consumption amount reduction mode is set. In this case as well, the total amount regulating unit 16 is configured to reduce the sum of the usage amounts of the color toner 5a and the clear toner 5b to the second threshold value or less by a reduction method according to the use of the clear toner 5b. Yes.

  Further, as will be described later, the total amount regulating unit 16 clears the total amount of the color toner 5a and the clear toner 5b used when the total amount is reduced to the second threshold value or less (when the toner consumption reduction mode is set). When the toner 5b is used for the purpose of adding gloss to the image, the amount of the clear toner 5b used at least in the highlight area of the image, compared with the case where the clear toner 5b is used for the purpose of adding the embedded information to the image. Is configured to reduce. The halftone processing unit 17 is configured to perform a predetermined dithering process on the image data corresponding to the CMYKT signal output from the total amount regulating unit 16.

  Next, the operation of the image processing unit 13 of the printer apparatus 100 according to the first embodiment will be described with reference to FIGS.

  First, the processing flow of the special toner image generation unit 15 during the operation of the image processing unit 13 will be described with reference to FIGS. 3 and 4. This processing flow is started when image data corresponding to the CMYK signal and X data are input from the color space conversion unit 14a to the special toner image generation unit 15.

  In this processing flow, first, as shown in FIG. 3, in step S1, image data corresponding to embedded information such as copy-forgery-inhibited pattern data and barcode data exists in the image data input from the color space conversion unit 14a. Processing to determine whether or not to do is performed. The determination process in step S1 is performed based on the contents of the X data input from the color space conversion unit 14a.

  If it is determined in step S1 that there is image data corresponding to the embedded information, the process proceeds to step S2. In this case, the clear toner 5b is used for adding embedded information to an image. In step S2, the value of the T (transparent) signal corresponding to the usage amount of the clear toner 5b is set to 179. This value 179 corresponds to about 70% of the maximum value 255 of data represented by an 8-bit binary number. Then, the process ends.

  On the other hand, if it is determined in step S1 that there is no image data corresponding to the embedded information, the process proceeds to step S3. In step S3, processing for determining whether the image data input from the color space conversion unit 14a corresponds to either a graphic object or an image object is executed. The determination process in step S3 is also performed based on the contents of the X data input from the color space conversion unit 14a, similarly to the determination process in step S1.

  In step S3, when it is determined that the image data input from the color space conversion unit 14a does not correspond to either the graphic object or the image object (when it is determined to correspond to the text object), the process proceeds to step S4. move on. In this case, the clear toner 5b is not used for the purpose of adding embedding information to the image or for the purpose of adding gloss to the image. In step S4, the value of the T signal corresponding to the usage amount of the clear toner 5b is set to zero. Then, the process ends.

  On the other hand, if it is determined in step S3 that the image data input from the color space conversion unit 14a corresponds to either a graphic object or an image object, the process proceeds to step S5. In this case, the clear toner 5b is mainly used for the purpose of imparting gloss.

  In step S5, the value of the T signal corresponding to the usage amount of the clear toner 5b is set to a value corresponding to the user setting (a value corresponding to the user specification in the glossiness specification mode). For example, as shown in FIG. 4, when the user has set “no gloss” in the glossiness designation mode, the value of the T signal corresponding to the usage amount of the clear toner 5b is set to zero. If the user has set “low gloss”, the value of the T signal is set to 75. If the user has set “high gloss”, the value of the T signal is set to 135. Then, the process ends.

  Next, referring to FIG. 5 and FIG. 6, details of a method for reducing the total usage amount of the color toner 5 a and the clear toner 5 b when the toner consumption reduction mode is not set in the printer device 100 according to the first embodiment. Will be described. 5 and 6 show the value of the CMYK signal input to the total amount regulating unit 16 and the value of the CMYK signal output from the total amount regulating unit 16 (and the value of the CMYKT signal obtained by adding the T signal to the CMYK signal). It is the graph which showed the relationship.

  First, with reference to FIG. 5, a reduction method in the case where the toner consumption reduction mode is not set and the clear toner 5b is used for the purpose of adding embedded information to an image will be described. In this case, since the transparent image data (T signal) expressed by the clear toner 5b is important, the value of the T signal output from the total amount regulating unit 16 (value corresponding to the usage amount of the clear toner 5b) is Is set to a relatively large value (a constant value). For example, as shown in FIG. 5, when the value of the T signal is T1, T1 = 179 is set. This value T1 corresponds to the vertical interval between the two solid line graphs in FIG.

  Here, it is assumed that the total usage amount of the color toner 5a and the clear toner 5b allowed in the printing process of the printer device 100 according to the first embodiment is A1 (= 714). That is, it is assumed that the total amount regulating unit 16 is configured to reduce the sum of the usage amounts of the color toner 5a and the clear toner 5b to 714 or less. In this case, A2 = A1 (714) −T1 (179) = 535, where A2 is the upper limit of the value of the CMYK signal output from the total amount regulating unit 16 (the value corresponding to the usage amount of the color toner 5a). .

  Therefore, as shown in FIG. 5, the total amount regulating unit 16 outputs the input signal as it is as the output signal (CMYK signal) when the value of the sum of the input signals (CMYK signal) is not more than 535 which is the upper limit value. . Further, when the value of the input signal exceeds 535, the total amount regulating unit 16 adjusts (reduces) the output signal so that the value of the output signal is 535 or less. That is, the total amount regulating unit 16 adjusts (reduces) the output signal (CMYK signal) so that the value of the output signal is maintained at a constant value (535).

The reduction process will be described more specifically. The values of the C signal, the M signal, the Y signal, and the K signal input to the total amount regulating unit 16 are C1, M1, Y1, and K1, respectively, and are output from the total amount regulating unit 16. When the values of the C signal, M signal, Y signal, and K signal are C2, M2, Y2, and K2, respectively, the following relational expressions (1) to (4) are established between these parameters.
K2 = K1 (1)
C2 = α × C1 (2)
M2 = α × M1 (3)
Y2 = α × Y1 (4)
In the above formulas (2) to (4), α = (A1−K1) / (C1 + M1 + Y1).

  Next, referring to FIG. 6, when the toner consumption reduction mode is not set and the clear toner 5b is not used for the purpose of giving the embedded information to the image (for the purpose of giving the image gloss). The reduction method in the case of being used will be described. In this case, the value of the T signal output from the total amount regulating unit 16 (the value corresponding to the usage amount of the clear toner 5b) is basically a value according to the user's designation in the glossiness designation mode (see FIG. 4). Set to

  However, when the clear toner 5b is used for the purpose of giving gloss to the image, the transparent image data (T signal) expressed by the clear toner 5b is not as important as the embedded information, but rather the color toner 5a is used. The reproduction of the gradation used is more important. For this reason, when the clear toner 5b is used for applying gloss to the image, the total amount regulating unit 16 is different from the case of FIG. 5 in which the value of the T signal is kept constant without being reduced. The value of the T signal is preferentially reduced. That is, assuming that the value of the T signal (the vertical interval between the two solid line graphs in FIG. 6) when the clear toner 5b is used for applying gloss to the image is T2, this value T2 is as shown in FIG. As shown in FIG. 4, the highlight area (area where the input signal value is 0 or more and 579 or less), the middle area (area where the input signal value is larger than 579 and 816 or less), and the shadow area (input signal). (Regions where the value of is greater than 816) are different from each other.

  For example, if the user sets “glossy” in the glossiness designation mode, T2 = 135 (value (corresponding to the amount of clear toner 5b used) used for gloss control is T2. 4). Accordingly, in this case, assuming that the upper limit value of the value of the CMYK signal output from the total amount regulating unit 16 (value corresponding to the usage amount of the color toner 5a) is A3, A3 = A1 (714) −T2 (135) = 579 It becomes.

  As a result, as shown in FIG. 6, the total amount restricting unit 16 determines that the input signal (CMYK signal) is equal to or less than the upper limit value of 579 (when an image highlight area is formed). As an output signal (CMYK signal). Then, the total amount regulating unit 16 performs adjustment (reduction) that gradually decreases the value T2 of the T signal from 135 to 10 as the value of the input signal exceeds 579. Specifically, when the value of the input signal is larger than 579 and equal to or smaller than 816 (when the middle region of the image is formed), the total amount regulating unit 16 sets the value T2 of the T signal from 135 to 10 Make adjustments (reductions) that gradually decrease until When the value of the input signal is larger than 816 (when a shadow region of the image is formed), adjustment is performed to keep the value T2 of the T signal constant at 10. Thus, even if the amount of the clear toner 5b used is reduced, a certain level of glossiness is originally ensured by the overlapping of the colors of the color toner 5a, so that a sufficient glossiness can be obtained.

  Next, referring to FIGS. 7 to 9, details of a method for reducing the total usage amount of the color toner 5a and the clear toner 5b when the toner consumption reduction mode is set in the printer apparatus 100 according to the first embodiment. Will be described.

  First, with reference to FIGS. 7 and 8, the details of the reduction method when the toner consumption reduction mode is set and the clear toner 5b is used for the purpose of adding embedded information to an image will be described. Also in this case, since the transparent image data (T signal) expressed by the clear toner 5b is important as in the case of FIG. 5, the value of the T signal (clear toner 5b) output from the total amount regulating unit 16 is important. Is set to a relatively large value (a constant value). However, in the case of FIGS. 7 and 8, since the toner consumption reduction mode is set, the value of the T signal is smaller than the value T1 (179) of the T signal in the case of FIG. It is preferable to set. Therefore, as shown in FIG. 7, the relationship between the usage amount of the clear toner 5b and the information recognition rate of the user is experimentally measured in advance, and the usage amount of the clear toner 5b before the information recognition rate starts to decrease is determined. , And adopted as the value T3 of the T signal. That is, T3 = 165 (a constant value) is set.

  Here, let B1 (= 678) be the sum of the usage amounts of the color toner 5a and the clear toner 5b that are allowed when the toner consumption reduction mode is set. In this case, B2 = B1 (678) −T3 (165) = 513, where B2 is the upper limit value of the CMYK signal value (value corresponding to the usage amount of the color toner 5a) output from the total amount regulating unit 16. . Therefore, as shown in FIG. 8, when the value of the input signal (CMYK signal) is 513 or less, which is the upper limit value, the total amount regulating unit 16 outputs the input signal as it is as an output signal (CMYK signal). In addition, when the value of the input signal exceeds 513, the total amount regulating unit 16 adjusts (reduces) the output signal so that the value of the output signal is 513 or less. That is, the total amount regulating unit 16 adjusts (reduces) the value of the output signal (CMYK signal) so that the value of the output signal is maintained at a constant value (513). At this time, the value T3 of the T signal (the vertical interval between the two solid line graphs in FIG. 8) remains constant at 165.

  Next, referring to FIG. 9, when the toner consumption reduction mode is set and the clear toner 5b is not used for the purpose of giving the embedded information to the image (used for the purpose of giving the image gloss). Will be described. Also in this case, as in the case of FIG. 6 described above, the total amount regulating unit 16 performs processing for preferentially reducing the value of the T signal corresponding to the usage amount of the clear toner 5b. Here, in the case of FIG. 9, unlike the case of FIG. 6, the toner consumption reduction mode is set, so the total amount regulating unit 16 preferentially reduces the value of the T signal and CMYK. The signal value is also reduced more than in FIG.

  Here, the value of the T signal output from the total amount regulating unit 16 (value corresponding to the usage amount of the clear toner 5b) is basically a value according to the user's designation in the glossiness designation mode (see FIG. 4). Set to For example, in the case of FIG. 6 where the user has set “high gloss” in the gloss level designation mode and the toner consumption reduction mode is not set, the value T2 of the T signal is 10 or more and 135 or less. It fluctuates within the range. However, in the case of FIG. 9, unlike the case of FIG. 6, since the toner consumption reduction mode is set, if the user has set “high gloss” in the gloss level designation mode, the T signal The value T4 fluctuates within a range of 10 to 108 which is narrower than the range of FIG. Accordingly, in the case of FIG. 9, assuming that the upper limit value of the value of the CMYK signal output from the total amount regulating unit 16 (the value corresponding to the usage amount of the color toner 5a) is B3, B3 = B1 (678) −T2. Minimum value (10) = 668. Note that the maximum value 108 of T4 corresponds to 80% of the maximum value 135 of the value T2 in FIG.

  As shown in FIG. 9, when the value of the input signal (CMYK signal) is larger than 816 (when a shadow area of the image is formed), the total amount regulating unit 16 sets the value T4 of the T signal to the minimum value. An adjustment is made to keep a certain 10 constant. Then, the total amount regulating unit 16 adjusts the value T4 of the T signal to gradually increase from 10 which is the minimum value as the value of the input signal becomes 816 or less. When the value T4 of the T signal reaches the maximum value 108, the value of the input signal is 560. Thereby, the total amount regulating unit 16 sets the value T4 of the T signal to the minimum value when the value of the input signal is 816 or less and larger than 560 (when the middle region of the image is formed). Adjustment is made to gradually increase from 10 to 108 which is the maximum value. Then, when the value of the input signal is 560 or less (when the highlight area of the image is formed), the total amount regulating unit 16 outputs the input signal as it is as an output signal (CMYK signal), and the T signal Adjustment is made to gradually decrease the value T4 from 108 to 10. Thus, even if the usage amount of the clear toner 5b in the highlight area is reduced, the sum of the usage amounts of the color toner 5a and the clear toner 5b is originally small in the highlight area, so that a certain degree of gloss can be obtained. is there.

  Next, referring to FIGS. 10A, 10B, and 10C, the color space conversion unit 14a, the black processing unit 14b, and the total amount restriction of the image processing unit 13 when the middle region of the image is formed. An example of output data from each of the units 16 will be described.

  In the case where the middle region of the image is formed, as an example, first, as shown in FIGS. 10A and 10B, the black processing unit 14b of the image processing unit 13 performs UCR processing, thereby The output corresponding to C, M, and Y of the toner 5a decreases, and the output of K increases. Then, as shown in FIGS. 10-2 and 10-3, the total amount regulating unit 16 reduces the output corresponding to T of the clear toner 5b.

  Next, referring to FIG. 11A, FIG. 11B, and FIG. 11C, the color space conversion unit 14a, the black processing unit 14b, and the total amount of the image processing unit 13 when the highlight region of the image is formed. An example of output data from each of the restriction units 16 will be described.

  In the case where the highlight area of the image is formed, as an example, first, as shown in FIGS. 11A and 11B, the black processing unit 14b of the image processing unit 13 performs the UCR process, The output corresponding to C, M, and Y of the color toner 5a decreases, and the output of K increases. Then, as shown in FIGS. 11-2 and 11-3, the total amount regulating unit 16 reduces the output corresponding to T of the clear toner 5b.

  As described above, when the middle region of the image is formed (see FIGS. 10A to 10C), and when the highlight region of the image is formed (see FIGS. 11A to 11C). In any case, the total amount regulating unit 16 mainly reduces the output corresponding to T of the clear toner 5b without largely reducing the output corresponding to C, M, Y, and K of the color toner 5a. Therefore, the gradation of the color toner 5a is not greatly impaired.

  In the first embodiment, as described above, the total amount regulating unit 16 reduces the total usage amount (total toner usage amount) of the color toner 5a and the clear toner 5b according to the application of the clear toner 5b. The first threshold value (see FIGS. 5 and 6) is configured to be reduced below. Accordingly, an optimum reduction method capable of achieving both the reproduction of the gradation of the image and the reduction of the total amount of toner used can be selected according to the use of the clear toner 5b. As a result, it is possible to appropriately reduce the total amount of toner used while ensuring the reproducibility of the gradation of the image.

  In the first embodiment, as described above, the total amount regulating unit 16 switches the reduction method according to whether or not the clear toner 5b is used for applying predetermined embedding information to the image. The total amount of toner 5a and clear toner 5b used is reduced. Thereby, it is possible to easily achieve both the reproduction of the gradation of the image and the reduction of the total amount of toner used depending on whether or not the clear toner 5b is used for the purpose of adding the embedded information to the image. The most suitable reduction method can be selected.

  In the first embodiment, as described above, the total amount regulating unit 16 preferentially reduces the usage amount of the color toner 5a when the clear toner 5b is used for applying embedded information to an image. The first reduction method (see FIGS. 5 and 8) is configured to reduce the total amount of color toner 5a and clear toner 5b used. Thereby, when priority is given to securing the clear toner 5b (when the clear toner 5b is used for the purpose of adding embedding information to an image), it is possible to suppress the reduction of the clear toner 5b. The total amount of toner used can be reduced while reliably embedding information in the image.

  In the first embodiment, as described above, the total amount regulating unit 16 preferentially reduces the usage amount of the clear toner 5b when the clear toner 5b is not used for the purpose of adding embedded information to an image. Thus, the second reduction method (see FIGS. 6 and 9) is configured to reduce the total amount of color toner 5a and clear toner 5b used. As a result, when it is not necessary to prioritize securing the clear toner 5b (when the clear toner 5b is used for the purpose of giving gloss to the image), priority is given to the reduction in the amount of color toner 5a used, and It is possible to prevent the tone reproducibility from being sufficiently secured.

  In the first embodiment, as described above, the total amount regulating unit 16 reduces the total usage amount of the color toner 5a and the clear toner 5b according to the setting of the user according to the use of the clear toner 5b. Thus, the second threshold value (see FIG. 8 and FIG. 9) smaller than the first threshold value (see FIG. 5 and FIG. 6) can be reduced. This makes it possible to further reduce the total amount of toner used while ensuring the reproducibility of the gradation of the image according to the user setting.

  In the first embodiment, as described above, the total amount regulating unit 16 reduces the total usage amount of the color toner 5a and the clear toner 5b to the second threshold value or less (see FIGS. 7 to 9). When the clear toner 5b is not used for the purpose of giving predetermined embedding information to the image (see FIG. 9), compared to the case where the clear toner 5b is used for the purpose of giving embedding information (see FIG. 8), The clear toner 5b is used at least in the highlight area of the image. Thereby, it is possible to appropriately suppress unnecessary use of the clear toner 5b.

(Second Embodiment)
Next, a printer device 200 according to the second embodiment will be described with reference to FIGS. 1, 2, and 12 to 14. The printer apparatus 200 is an example of an “image forming apparatus”. In the second embodiment, when the toner consumption reduction mode is not set, the image is so formed that the pile height (the height of the layer formed on the surface of the paper by the color toner 5a and the clear toner 5b) is substantially uniform. An example in which formation is performed will be described.

  Also in the second embodiment, similar to the first embodiment, the special toner image generation unit 215 (see FIG. 2) of the image processing unit 213 (see FIG. 1) performs the same processing as the processing flow of FIG. Operates based on flow. However, in the second embodiment, the contents of the process executed in step S5 in FIG. 3 (how to determine the value of the T signal corresponding to the usage amount of the clear toner 5b) are different from those in the first embodiment.

  Specifically, as illustrated in FIG. 12, the special toner image generation unit 215 according to the second embodiment determines the output of the T signal as a function with respect to the sum of input signals (CMYK signal). Of the two solid line graphs in FIG. 12, the upper solid line graph corresponds to the case where the user has set “glossy” in the glossiness designation mode, and the lower solid line graph indicates that the user is glossy. This corresponds to the case where “low gloss” is set in the degree designation mode.

  Thereby, in the second embodiment, the total amount regulating unit 216 (see FIG. 2) is used when the toner consumption reduction mode is not set and the clear toner 5b is used for the purpose of adding gloss to the image. The total use amount of the color toner 5a and the clear toner 5b is adjusted (reduced) as shown in FIG.

  That is, as shown in FIG. 13, in the second embodiment, when the toner consumption reduction mode is not set and the clear toner 5b is used for the purpose of adding gloss to the image, the color toner 5a The upper limit of the value of the output signal (CMYK signal) corresponding to the usage amount changes according to the value of the input signal. The value T5 of the T signal corresponding to the usage amount of the clear toner 5b (the vertical interval between the two solid line graphs in FIG. 13) is the value of the CMYKT signal obtained by adding the T signal to the CMYK signal (pile height). The corresponding value) is set to be constant (714) regardless of the value of the input signal.

  In the second embodiment, the total amount regulating unit 216 (see FIG. 2) is a color toner when the toner consumption reduction mode is set and the clear toner 5b is used for the purpose of adding gloss to an image. The total use amount of 5a and clear toner 5b is adjusted (reduced) as shown in FIG.

  That is, as shown in FIG. 14, in the second embodiment, the color toner 5a is used when the toner consumption reduction mode is set and the clear toner 5b is used for applying gloss to the image. The upper limit of the value of the output signal (CMYK signal) corresponding to the amount changes according to the value of the input signal, as in FIG. Here, in the case of FIG. 14, unlike the case of FIG. 13 described above, the toner consumption reduction mode is set, so that the pile height (value corresponding to the value of the CMYKT signal) does not necessarily have to be uniform. For this reason, in FIG. 14, when an image highlight area is formed (when the total value of the input signals is 560 or less), the value T6 of the T signal corresponding to the amount of clear toner 5b used is Compared with the case of 13, it is greatly reduced. However, in the case of FIG. 14, the value T6 of the T signal in the highlight region is maintained at a constant value (118).

  The other configurations, operations, and effects of the second embodiment are the same as those of the first embodiment.

(Third embodiment)
Next, a printer apparatus 300 according to the third embodiment will be described with reference to FIGS. 1, 2, and 15. The printer apparatus 300 is an example of an “image forming apparatus”. In the third embodiment, the pile height is not necessarily uniform when the toner consumption reduction mode is set. Unlike the second embodiment, the pile height is substantially uniform even when the toner consumption reduction mode is set. An example in which image formation is performed will be described.

  Also in the third embodiment, similar to the second embodiment, the special toner image generation unit 315 (see FIG. 2) of the image processing unit 313 (see FIG. 1) performs the same processing flow as the processing flow of FIG. Operates based on. However, in the third embodiment, the content of the process executed in step S5 in FIG. 3 (how to determine the value of the T signal corresponding to the usage amount of the clear toner 5b) is different from that in the second embodiment.

  In other words, in the third embodiment, the total amount regulating unit 316 (see FIG. 2) is a color toner when the toner consumption reduction mode is set and the clear toner 5b is used for the purpose of adding gloss to an image. The total usage amount of 5a and clear toner 5b is adjusted (reduced) as shown in FIG.

  As shown in FIG. 15, in the third embodiment, when the middle region and the shadow region of the image are formed (when the sum of the input signals (CMYK signal) is greater than 560), the output signal (CMYK signal) And two solid line graphs corresponding to the CMYKT signal) overlap. That is, in the third embodiment, when the middle region and the shadow region of the image are formed, the value of the T signal (the value corresponding to the usage amount of the clear toner 5b) is set to zero. Even in such a setting, since the colors (C, M, Y, and K) of the color toner 5a are originally largely overlapped in the middle area and the shadow area, and a certain level of gloss is already obtained, There is no problem. In the third embodiment, as shown in FIG. 15, when the highlight area of the image is formed (when the total value of the input signals is 560 or less), the T signal is set so that the pile height is uniform. Is set to a value corresponding to the value of the input signal. As a result, the pile height is made uniform while reducing the amount of color toner 5a and clear toner 5b used.

  The other configurations, operations, and effects of the third embodiment are the same as those of the second embodiment.

  Here, the image forming program (image processing program) executed by the printer apparatus according to the first to third embodiments is provided by being incorporated in advance in a ROM or the like. This image forming program is a file in an installable or executable format and is a computer-readable recording such as a CD-ROM, a flexible disk (FD), a CD-R, or a DVD (Digital Versatile Disk). It may be configured to be provided in a state recorded on a medium. Further, the image forming program may be stored on a computer connected to a network such as the Internet and provided by downloading via the network. Further, this image forming program may be configured to be provided or distributed via a network such as the Internet.

  The image forming program has a module configuration including the above-described units (color conversion processing unit, special toner image generating unit, and total amount regulating unit). As actual hardware, a CPU (processor) is installed from the ROM to the above-described unit. By reading and executing the image forming program, the above-described units are loaded onto the main storage device, and a color conversion processing unit, a special toner image generation unit, and a total amount regulating unit are generated on the main storage device. .

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first to third embodiments, an example in which the present invention is applied to a printer apparatus as an example of an image forming apparatus has been described, but the present invention is not limited to this. The present invention is also applicable to an image forming apparatus other than a printer, such as a multifunction peripheral having at least two functions among a copy function, a printer function, a scanner function, and a facsimile function, a copying machine, a scanner device, and a facsimile device. can do.

  In the above embodiment, the clear toner is used as an example of the special color toner (second toner) of the present invention. However, the present invention is not limited to this. In the present invention, it is also possible to use a special color toner other than the process color such as green or orange as the special color toner. When a special color toner other than the process color is used, it is possible to reproduce a color that usually falls outside the gamut range, and one of the main advantages is that the color reproduction range is widened.

  Here, the special color toners other than the process color as described above are not only used for high-precision color separation of the original image, but also for the purpose of stamping a specific logo mark with a specific color such as a company logo mark. Sometimes used. In such a case, the special color toner is used as a color reproduction unit of the original (input) image and also as a unit for giving specific information to the image.

  Therefore, it is possible to replace the method for regulating the total amount of clear toner and color toner as shown in the first to third embodiments with the method for regulating the total amount of special color toner and color toner. That is, using special color toner for the purpose of stamping a specific logo mark with a specific color is considered to give embedding information in a broad sense to the image. As described above, it is necessary to preferentially secure the special color toner over the color toner. On the other hand, when the special color toner is used to obtain highly accurate color reproduction, it is not necessary to secure the special color toner preferentially over the color toner, and the total amount restriction process similar to the color toner other than K is performed. Do.

Specifically, when green (G) toner is used as the special color toner, the values of the C signal, the M signal, the Y signal, the K signal, and the G signal input to the total amount regulating unit are set to C3, M3, Y3, and K3, respectively. And G1, and when the values of the C signal, M signal, Y signal, K signal, and G signal output from the total amount regulating unit are C4, M4, Y4, K4, and G2, respectively, between these parameters, The following relational expressions (5) to (9) are established.
K4 = K3 (5)
C4 = β × C3 (6)
M4 = β × M3 (7)
Y4 = β × Y3 (8)
G2 = β × G1 (9)
In the above equations (6) to (9), β = (upper limit value of output signal value−K) / (C + M + Y + G).

  In the above description, the case where special color toner is used for the purpose of stamping a specific logo mark using a specific color has been described. However, the special color toner is used for description of tint block data, marking data, and barcode data. It is the same even if there is.

5a Color toner (first toner, colored toner)
5b Clear toner (second toner, special color toner)
14 color conversion processing unit (first determining unit)
15 Special toner image generation unit (second determination unit)
16 Total amount regulation department (reduction department)
100, 200, 300 Printer device (image forming device)

JP 2007-49338 A

Claims (8)

A first determination unit for determining a usage amount of a first toner mainly used for reproducing the gradation of an image formed on a sheet;
A second determining unit that determines a usage amount of a second toner mainly used for an application different from the first toner;
A reception unit for receiving an operation mode setting by a user;
When the first operation mode is set as the operation mode, the sum of the usage amounts of the first toner and the second toner determined by the first determination unit and the second determination unit, respectively, is used as the second toner. In the reduction method according to the application, the first threshold is used to reduce the total amount of the first toner and the second toner to be further reduced as compared with the first operation mode. When the second operation mode is set, the total usage amount of the first toner and the second toner is reduced to a value equal to or smaller than the second threshold value that is smaller than the first threshold value by a reduction method according to the use of the second toner. An image forming apparatus comprising: a reduction unit that reduces.   The reduction unit switches the reduction method according to whether or not the second toner is used for giving predetermined embedding information to the image, thereby using the usage amounts of the first toner and the second toner. The image forming apparatus according to claim 1, wherein the image forming apparatus is configured to reduce a total sum of the image forming apparatus.   When the second toner is used for the purpose of adding the embedded information to the image, the reduction unit uses a first reduction method that preferentially reduces the usage amount of the first toner. The image forming apparatus according to claim 2, wherein the image forming apparatus is configured to reduce a total amount of the second toner used.   When the second toner is not used for applying the embedded information to the image, the reduction unit uses a second reduction method that preferentially reduces the amount of the second toner used. The image forming apparatus according to claim 2, wherein the image forming apparatus is configured to reduce a total amount of toner and the second toner used.   The reduction unit is used for an application in which the second toner gives predetermined embedding information to the image when the total amount of the first toner and the second toner is reduced to the second threshold value or less. If not, the second toner is configured to reduce the amount of the second toner used at least in the highlight area of the image, compared to the case where the second toner is used for the application of the embedded information. The image forming apparatus according to claim 1. The first toner is a colored toner corresponding to a process color mainly used for reproducing the gradation of the image,
The said 2nd toner is a special color toner containing clear toner mainly used for the use which provides predetermined | prescribed embedding information to the said image, and the use which provides the said image with glossiness. The image forming apparatus described in the item. Determining a usage amount of a first toner mainly used in an application for reproducing a gradation of an image formed on a sheet;
Determining a usage amount of a second toner mainly used for an application different from the first toner;
Receiving a setting of an operation mode by a user;
When the first operation mode is set as the operation mode, the determined sum of the usage amounts of the first toner and the second toner is reduced to a value equal to or less than the first threshold value by a reduction method according to the use of the second toner. And when the second operation mode is set as the operation mode to further reduce the total amount of the first toner and the second toner used than the first operation mode, the first toner And a step of reducing the total amount of the second toner used to a second threshold value that is smaller than the first threshold value by a reduction method according to the use of the second toner. Determining a usage amount of a first toner mainly used in an application for reproducing a gradation of an image formed on a sheet;
Determining a usage amount of a second toner mainly used for an application different from the first toner;
Receiving a setting of an operation mode by a user;
When the first operation mode is set as the operation mode, the determined sum of the usage amounts of the first toner and the second toner is reduced to a value equal to or less than the first threshold value by a reduction method according to the use of the second toner. And when the second operation mode is set as the operation mode to further reduce the total amount of the first toner and the second toner used than the first operation mode, the first toner And an image for causing a computer to execute a step of reducing the total amount of the second toner used to a second threshold value that is smaller than the first threshold value by a reduction method according to the use of the second toner. Formation program.

Images