JP2022029211A - Image forming apparatus - Google Patents

Abstract

To obtain an image forming apparatus that prevents a reduction in visibility of an image on a print product.SOLUTION: An image condition determination unit 23 determines whether to inhibit the density inversion of a target image on the basis of an object in the target image based on image data. A density condition determination unit 24 determines whether to perform the density inversion on the basis of the density of the target image. A density inversion processing unit 25 performs the density inversion (a) when the image condition determination unit 23 determines not to inhibit the density inversion and the density condition determination unit 24 determines to perform the density inversion, and does not perform the density inversion (b) when the image condition determination unit 23 determines to inhibit the density inversion or the density condition determination unit 24 determines not to perform the density inversion. After that, a print processing unit 26 causes a printing device 11 to print either one of the target image and the target image after the density inversion.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image forming apparatus.

One image forming apparatus compares the predicted required amount of toner in a density-inverted image and a non-density-reversed image based on drawing data, and the predicted required amount of the density-inverted image is smaller than the predicted required amount of the non-density-reversed image. In this case, the density of the image is inverted based on the drawing data and printed (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2002-196618

However, if density inversion and printing are performed uniformly based on the comparison result of the predicted required amount as in the above-mentioned image forming apparatus, the visibility of the image on the print product deteriorates depending on the image to be printed. Sometimes.

The present invention has been made in view of the above problems, and an object of the present invention is to obtain an image forming apparatus that suppresses deterioration of visibility of an image on a print product.

The image forming apparatus according to the present invention is based on an image condition determination unit that determines whether or not to prohibit density inversion of the target image based on an object in the target image based on image data, and a density of the target image. The density condition determination unit for determining whether or not to perform the density reversal and (a) the image condition determination unit determine that the density reversal is not prohibited, and the density condition determination unit determines that the density reversal is performed. If this is the case, the density reversal is performed, and (b) the image condition determination unit determines that the density reversal is prohibited, or the density condition determination unit determines that the density reversal is not performed. It includes a density inversion processing unit that does not perform density inversion, and a print processing unit that causes a printing device to print any of the target image and the target image that has undergone density inversion by the density inversion processing unit.

According to the present invention, it is possible to obtain an image forming apparatus that suppresses deterioration of visibility of an image on a print product.

The above or other objects, features and advantages of the present invention will be further demonstrated from the following detailed description, along with the accompanying drawings.

FIG. 1 is a block diagram showing a configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a flowchart illustrating the operation of the image forming apparatus according to the first embodiment. FIG. 3 is a diagram showing an example of a target image in the first embodiment and an example of a print image obtained from the target image. FIG. 4 is a flowchart illustrating the operation of the image forming apparatus according to the second embodiment. FIG. 5 is a diagram showing an example of a target image in the second embodiment and an example of a print image obtained from the target image.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1.

FIG. 1 is a block diagram showing a configuration of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus shown in FIG. 1 has a printer function and a scanner function, and includes a printing device 11, an image reading device 12, an operation panel 13, a storage device 14, a communication device 15, and a controller 16.

The printing device 11 is an internal device that prints a print image based on print image data on print paper page by page by an electrophotographic method, an inkjet method, or the like.

Further, the image reading device 12 is an internal device that optically reads an image of a document such as a print product page by page and generates image data of each page image.

Further, the operation panel 13 is arranged on the surface of the housing of the image forming apparatus, and includes a display device for displaying various information to the user and an input device for detecting the user operation. As the display device, for example, a liquid crystal display is used. As the input device, a touch panel for hard keys and soft keys is used.

Further, the storage device 14 is a device capable of storing various data and programs.

Further, the communication device 15 is a circuit that is connected to a computer network (not shown) and performs data communication with another device (host device or the like) connected to the network.

Further, the controller 16 has a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and loads a program from the ROM, the storage device 14, and the like into the RAM, and the program is loaded by the CPU. By executing it, it operates as various processing units.

In this embodiment, the controller 16 operates as an image acquisition unit 21, an area separation processing unit 22, an image condition determination unit 23, a density condition determination unit 24, a density inversion processing unit 25, and a print processing unit 26.

By acquiring the image data, the image acquisition unit 21 acquires the target image based on the image data. In the case of a copy job, the image acquisition unit 21 acquires the image data of the original image read by the image reading device 12, and sets the original image as the target image. In the case of a print job, the image acquisition unit 21 acquires the image data of the original image specified by the print request or the like received via the communication device 15, and sets the original image as the target image.

The area separation processing unit 22 performs existing area separation processing on the above-mentioned target image, and detects character objects, image objects (photographic image objects, graphic image objects, etc.) in the target image.

The image condition determination unit 23 determines whether or not to prohibit density inversion of the target image based on the above-mentioned object in the target image.

In the first embodiment, the image condition determination unit 23 has a density when the character object is in the target image and the background of the character object (that is, a predetermined area around the character object) has a lower density than the character object. It is determined that inversion is prohibited.

The density condition determination unit 24 determines whether or not to perform density inversion based on the density of the above-mentioned target image. Specifically, the density condition determination unit 24 consumes a color material (consumption of toner and ink) when performing density inversion based on the density of the target image (that is, the pixel value of each pixel in the image data). , And when the amount of color material consumed when density inversion is not performed is specified and the amount of color material consumed when density inversion is performed is less than the amount of color material consumed when density inversion is not performed, density inversion is performed. judge.

The density inversion processing unit 25 performs density inversion when (a) the image condition determination unit 23 determines that the density inversion is not prohibited and the density condition determination unit 24 determines that the density inversion is performed, and (b). When the image condition determination unit 23 determines that the density inversion is prohibited, or when the density condition determination unit 24 determines that the density inversion is not performed, the density inversion is not performed.

For example, when the maximum density of the target image is Dmax and the density range of the target image is 0 to Dmax, and the density of each pixel is D, the density D'of each pixel after density inversion is the formula D'=. Calculated by Dmax-D.

The print processing unit 26 controls the print device 11 based on the print image data to execute printing. The print image data is raster image data obtained by image processing such as half toning. The print processing unit 26 causes the printing apparatus 11 to print either the above-mentioned target image or the target image whose density has been inverted by the density inversion processing unit 25 as a print image.

Next, the operation of the image forming apparatus according to the first embodiment will be described. FIG. 2 is a flowchart illustrating the operation of the image forming apparatus according to the first embodiment. FIG. 3 is a diagram showing an example of a target image in the first embodiment and an example of a print image obtained from the target image.

When the target image is acquired by the image acquisition unit 21 (step S1), the region separation processing unit 22 performs region separation processing on the target image (step S2).

Then, the image condition determination unit 23 determines whether or not there is a character object in the target image (step S3), and if there is a character object in the target image, whether the background of the character object has a lower density than the character object. It is determined whether or not (step S4).

Then, when there is no character object in the target image, or when the background of the character object is not lower than the character object when there is a character object in the target image, the density condition determination unit 24 determines the density distribution of the target image. Based on (that is, the pixel value of each pixel), the color material consumption before and after the density inversion is specified (step S5), and whether or not the color material consumption after the density inversion is smaller than the color material consumption before the density inversion. (Step S6).

Then, when the color material consumption after the density inversion is smaller than the color material consumption before the density inversion, the density inversion processing unit 25 performs the density inversion for the entire area of the target image (step S7). If not, the concentration is not reversed.

Further, in steps S3 and S4, if there is a character object in the target image and it is determined that the background of the character object has a lower density than the character object, density inversion is prohibited and in steps S5 to S7. The determination of whether to execute the density inversion and the density inversion are skipped.

After that, the print processing unit 26 causes the printing device 11 to print the target image after the density inversion when the density inversion is performed, and when not, the print processing unit 26 prints the target image without the density inversion. It is printed on No. 11 (step S8).

For example, in the example shown in FIG. 3, since the target image 101-1 has a background density higher than the density of the character object, the density of the target image 101-1 is inverted to generate and print the print image 102-1. .. Further, in the target image 101-2, since the background density of the area 111 including the character object is higher than the density of the character object, the entire area of the target image 101-2 (area 111 and other areas 112) is inverted in density. As a result, the print image 102-2 is generated and printed. Further, in the target image 101-3, since the background density of the area 111 including the character object is lower than the density of the character object, the density inversion is not performed, and the target image 101-3 is printed as the print image 102-3. To.

As described above, according to the first embodiment, the image condition determination unit 23 determines whether or not to prohibit the density inversion of the target image based on the object in the target image based on the image data. The density condition determination unit 24 determines whether or not to perform density inversion based on the density of the target image. Then, the density inversion processing unit 25 performs density inversion when (a) the image condition determination unit 23 determines that the density inversion is not prohibited and the density condition determination unit 24 determines that the density inversion is performed. b) If the image condition determination unit 23 determines that the density inversion is prohibited, or if the density condition determination unit 24 determines that the density inversion is not performed, the density inversion is not performed. After that, the print processing unit 26 causes the printing device 11 to print either the target image or the target image after density inversion.

As a result, density inversion is prohibited according to the type and density of the object in the target image, and when the visibility of the object tends to decrease due to density inversion, density inversion is not performed, so that the visibility of the image on the print product is visible. The decrease is suppressed.

Embodiment 2.

In the second embodiment, when the density condition determination unit 24 determines that the image condition determination unit 23 prohibits density inversion of the target image, and there is an image object in the target image, the density condition determination unit 24 is based on the density of the image object. It is determined whether or not to invert the density of the image object. Then, in the second embodiment, when the density reversal processing unit 25 determines that the density reversal of the image object is performed by the density condition determination unit 24, the density reversal processing unit 25 does not perform the density reversal for the portion of the target image other than the image object. The density of the image object is inverted, and the print processing unit 26 causes the printing device 11 to print the target image whose density of the image object is inverted by the density inversion processing unit 25.

Next, the operation of the image forming apparatus according to the second embodiment will be described. FIG. 4 is a flowchart illustrating the operation of the image forming apparatus according to the second embodiment. FIG. 5 is a diagram showing an example of a target image in the second embodiment and an example of a print image obtained from the target image.

In the second embodiment, the processes of steps S11 to S18 are executed in the same manner as the processes of steps S1 to S8 described above. Then, in the second embodiment, when it is determined in steps S13 and S14 that there is a character object in the target image and the background of the character object has a lower density than the character object, the following processing is executed. Will be done.

First, the image condition determination unit 23 determines whether or not there is an image object in the target image (step S21), and if there is an image object in the target image, the density condition determination unit 24 determines the image object. Based on the density distribution of, the color material consumption before and after the density inversion of the image object is specified (step S22), and the color material consumption after the density inversion of the image object is smaller than the color material consumption before the density inversion. Whether or not it is determined (step S23).

Then, when the color material consumption after the density inversion of the image object is smaller than the color material consumption before the density inversion, the density inversion processing unit 25 reverses the density of only the image object among the target images. (Step S24), and if not, the density inversion of the image object is not performed.

On the other hand, if there is no image object in the target image, the processes of steps S22 to S24 are skipped.

After that, when (a) the density inversion of the entire target image is performed (step S17), the print processing unit 26 causes the printing device 11 to print the target image after the density inversion of the entire target image, and (b) the image. When the density inversion of the object is performed (step S24), the target image after the density inversion of the image object is printed on the printing device 11, and (c) when the density inversion is not performed at all, the density inversion is performed. The printing device 11 is made to print the target image that has not been performed (step S18).

For example, in the example shown in FIG. 5, in the target image 211-1, since the background density of the character object is lower than the density of the character object, the density inversion of the entire target image 211-1 is not performed, but the photograph (gradient image). The density of the object 211 is inverted, and the printed image 202-1 is generated and printed. Further, in the target image 201-2, since the background density of the character object is lower than the density of the character object, the density inversion of the entire target image 201-1 is not performed, but the density inversion of the graphic object 212 is performed and the print is performed. Image 202-2 is generated and printed.

Since other configurations and operations of the image forming apparatus according to the second embodiment are the same as those of the first embodiment, the description thereof will be omitted.

As described above, according to the second embodiment, even if the density inversion of the entire target image is prohibited, the density inversion can be performed individually for the image object, so that the visibility of the character object can be ensured. The amount of coloring material consumed is suppressed.

It should be noted that various changes and modifications to the above-described embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the intent and scope of the subject and without diminishing the intended benefits. That is, it is intended that such changes and amendments are included in the claims.

The present invention is applicable to, for example, an image forming apparatus.

11 Printing device 23 Image condition judgment unit 24 Density condition judgment unit 25 Density inversion processing unit 26 Print processing unit

Claims (4)

An image condition determination unit that determines whether or not to prohibit density inversion of the target image based on an object in the target image based on image data.
A density condition determination unit that determines whether or not to perform the density inversion based on the density of the target image,
(A) When the image condition determination unit determines that the density inversion is not prohibited and the density condition determination unit determines that the density inversion is performed, the density inversion is performed, and (b) the image condition determination. When it is determined by the unit that the concentration inversion is prohibited, or when the concentration condition determination unit determines that the concentration inversion is not performed, the concentration inversion processing unit that does not perform the concentration inversion and the concentration inversion processing unit.
A print processing unit that causes a printing apparatus to print any of the target image and the target image whose density has been inverted by the density inversion processing unit.
An image forming apparatus comprising. The image condition determination unit is characterized in that if there is a character object in the target image and the background of the character object has a lower density than that of the character object, the image condition determination unit determines that the density inversion is prohibited. 1. The image forming apparatus according to 1. When the density condition determination unit determines that the density inversion is prohibited by the image condition determination unit, when the image object is in the target image, the density condition inversion of the image object is based on the density of the image object. Judge whether or not to do
When the density inversion processing unit determines that the density condition determination unit performs density inversion of the image object, the density inversion processing unit does not perform density inversion for the portion of the target image other than the image object, and the density of the image object. Invert and
The print processing unit causes the printing apparatus to print the target image whose density of the image object has been inverted by the density inversion processing unit.
The image forming apparatus according to claim 1. Based on the density of the target image, the density condition determination unit specifies the amount of color material consumed when the density is reversed and the amount of color material consumed when the density is not reversed, and performs the density inversion. One of claims 1 to 3, wherein when the amount of the color material consumed in the case is smaller than the amount of the color material consumed in the case where the density reversal is not performed, it is determined that the density reversal is performed. The image forming apparatus according to item 1.

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