JPH05225392A - Binarizing processor - Google Patents

Abstract

PURPOSE:To attain appropriate and faithful image reproduction by variably setting up a binarizing threshold in each picture element(PE) by using density information or density changing information around a remarked picture element(PE). CONSTITUTION:A target is read out by an image input device 1, its density image is formed and respective PE data of the density image are stored in an image memory 2 in each PE. An area setting device 3 sets up a local area around a remarked PE on the density image and a reference value calculating device 4 and an adding value calculating device 5 respectively calculate a reference value and an adding value based upon the PE data of a prescribed PE in the local area. A binarizing threshold determining device 6 adds the adding value to the reference value to calculate a binarizing threshold and a binarized output device 7 binarizes the remarked PE by the binarizing threshold and outputs the binarized result.

Description

Detailed Description of the Invention

[0001]

This invention relates to an image scanner,
Technology applied to facsimiles, copiers, etc.,
The present invention relates to a binarization processing device used for binarizing a grayscale image read from an object.

[0002]

2. Description of the Related Art Conventionally, in such an apparatus, a grayscale image read from a document such as a newspaper or a photograph is converted from an analog amount into a digital amount, and the grayscale is composed of pixel data whose density is expressed by 256 gradations. After obtaining the image, this grayscale image is binarized by a fixed binarization threshold having an intermediate density gradation to generate and output a binary image.

[0003]

However, the fixed 2
In the binarization method using the threshold value, the pixel data is 2
2 if it is smaller than the threshold value
Value data (for example, “0”) is converted, and conversely, if the pixel data is slightly larger than the binarization threshold value, it is converted to binary data (for example, “1”) representing a white pixel.
It is difficult to faithfully reproduce each dot of a halftone dot image for those having an intermediate density such as a halftone dot image. Therefore, when the grayscale image of the halftone dot image is binarized, an appropriate binary image output cannot be obtained, and the moire pattern is also expressed, and the binary image becomes dirty.

Further, in the case of an object having a rough cloth such as a newspaper, the unevenness of a black background or a white background appears as noise in the binary image, and the background such as characters is a colored background.
There is a problem that the characters are not reproduced clearly. Furthermore, regarding thin lines, there is a problem that thin lines disappear from the binary image and it is difficult to reproduce a faithful image.

The present invention has been made in view of the above-mentioned problem. By appropriately setting the binarization threshold value for each pixel using the density information and density change information around the pixel of interest, an appropriate and faithful operation is achieved. It is an object of the present invention to provide a binarization processing device capable of reproducing various images.

[0006]

According to a first aspect of the present invention, there is provided a binarization processing device for binarizing each pixel data of a grayscale image, the image inputting means generating the grayscale image, Area setting means for setting a local area including the pixel of interest around the pixel of interest on the grayscale image, and density for extracting the density level of the grayscale image in the local area from pixel data of a predetermined pixel included in the local area Level extraction means, and binarization threshold value determination means for determining a binarization threshold value for binarizing the pixel data of the pixel of interest according to the density level extracted by the density level extraction means; Two
And a binarization unit for binarizing the pixel data of the pixel of interest by the binarization threshold value determined by the binarization threshold value determination unit.

A binarization processing apparatus according to a second aspect of the present invention comprises image input means for generating a grayscale image, and area setting means for setting a local area including the pixel of interest around the pixel of interest on the grayscale image. Density level extraction means for extracting a density level of a grayscale image in a local area from pixel data of a predetermined pixel included in the local area, pixel data of a predetermined pixel included in the local area, and pixel data of a target pixel And a density difference calculating means for calculating a density difference between the density level and the density level extracted by the density level extracting means and the density difference calculated by the density difference calculating means. Binarizing threshold value deciding means for deciding a binarizing threshold value for binarization processing, and binarizing the pixel data of the target pixel by the binarizing threshold value decided by the binarizing threshold value deciding means. It is obtained by a binarizing means for processing.

A binarization processing apparatus according to a third aspect of the present invention includes image input means for generating a grayscale image, area setting means for setting different local areas around a pixel of interest on the grayscale image, and Density level extraction means for extracting the density level of the grayscale image in each local area from the pixel data of a predetermined pixel included in each local area, and either density extracted by the density level extraction means based on the position of the pixel of interest. A binarization threshold value determining means for selecting a level and determining a binarization threshold value for binarizing the pixel data of the pixel of interest according to the density level; and the binarization threshold value determining means. And a binarizing unit for binarizing the pixel data of the pixel of interest according to the determined binarization threshold value.

A binarization processing apparatus according to a fourth aspect of the present invention is an image inputting means for generating a grayscale image, and a region setting means for setting a different local region including the pixel of interest around the pixel of interest on the grayscale image. And density level extraction means for extracting a density level of a grayscale image in each local area from pixel data of a predetermined pixel included in each local area, and pixel data of a predetermined pixel included in any one of the local areas. A density difference calculating means for calculating the density difference between the pixel data of the pixel of interest and one of the density levels extracted by the density level extracting means based on the position of the pixel of interest and selecting the density level and the density difference. A binarization threshold value determining means for determining a binarization threshold value for binarizing the pixel data of the pixel of interest according to the density difference calculated by the calculation means;
Pixel data of the pixel of interest is binarized by the binarization threshold value determined by the binarization threshold value determination means 2
And a value conversion means.

According to a fifth aspect of the present invention, each of the above means is provided in any one of an image scanner, a facsimile and a copying machine.

[0011]

In the binarization processing device according to the invention of claim 1,
Since the binarization threshold value is variably set for each pixel using the density information around the pixel of interest, the binarization threshold value is set high in a black background portion such as a character and the binarization threshold value in a white background portion of the background. Is set to a low value and the binarization threshold is set to an intermediate value in the halftone part, so that the black background such as characters and the white background are faithfully reproduced, and the halftone part corresponds to the binary change corresponding to the density change. It becomes an image.

In the binarization processing device according to the second aspect of the present invention, since the binarization threshold value is variably set for each pixel using the density information and density change information around the pixel of interest, a black background portion such as a character A binarization threshold that makes it difficult to pick up density changes in areas where density changes are small, such as white background
In addition, it is easy to pick up the density change in a part where the density change is large in a narrow region such as a halftone picture or where there is a thin line.
By setting each of the threshold values, a black background,
The white background, the dots in the halftone dot photograph, and the fine lines are faithfully reproduced.

In the binarization processing apparatus according to the third aspect of the present invention, any one of the local regions is selected based on the position of the pixel of interest, and the density information around the pixel of interest in the local region is used to select 2 for each pixel. Since the threshold value is variably set, it is possible to prevent the moire pattern from being generated due to the dot period of the halftone picture and the sampling period of the pixel data.

In the binarization processing apparatus according to the invention of claim 4, any one of the local regions is selected based on the position of the pixel of interest, and the density information and the density change information around the pixel of interest in the local region are used. Since the binarization threshold is variably set for each pixel, generation of a moire pattern due to the dot period of the halftone dot photograph and the sampling period of the pixel data is prevented, and the black background, the white background, the dot of the halftone photograph and ，
Fine lines are faithfully reproduced.

According to the invention of claim 5, an image scanner, a facsimile machine and a copying machine having the above-mentioned excellent characteristics can be obtained.

[0016]

FIG. 1 shows a circuit configuration of a binarization processing apparatus according to an embodiment of the present invention. An image input apparatus 1, an image memory 2, an area setting apparatus 3, a reference value calculation apparatus 4 and an addition. A value calculation device 5, a binarization threshold value determination device 6, a binarization output device 7 and the like are included as components.

The image input device 1 has an image pickup device such as a CCD, and reads a character or a figure from an object to generate a grayscale image. The analog grayscale image signal is converted into a digital volume, and pixel data whose density is represented by 256 gradations (0 to 255) is obtained.

The image memory 2 stores each pixel data in pixel units, and the data structure of each pixel data is illustrated in FIG. In the figure, each number is the density gradation of each pixel data, and the smaller the number, the greater the density.

The area setting device 3 is for setting a local area including the pixel of interest around the pixel of interest on the grayscale image, and FIGS. 3 and 4 show examples of setting the local area. In the example of FIG. 3, 20 is a pixel of interest at the position of coordinates (i, j), 24 is a local area, and in this local area 24,
The pixel of interest 20 and its surrounding coordinates (i-1, j-
1) Pixel 21 at each position of (i-1, j) (i, j-1)
~ 23 are included. In addition, D, A, B, and C are each pixel 20-
It means 23 pixel data.

In the example of FIG. 4, 20 is the pixel of interest at the position of coordinates (i, j), and 24 and 29 are local regions. In the one local area 24, the pixel of interest 20 and the pixels 21 to 23 at respective positions of coordinates (i-1, j-1) (i-1, j) (i, j-1) around the pixel of interest 20 are provided. In the other local area 29, the coordinates (i-2, j-1) (i-2, j) (i are included.
+1, j-1) pixel 25 at each position of (i + 1, j-1)
~ 28 are included. In addition, D, A, B, and C are each pixel 20-
23 pixel data, E, F, G, H are pixels 25 to 2
The 8 pixel data means each.

Returning to FIG. 1, the reference value calculation device 4 and the addition value calculation device 5 are a reference value and a reference value for determining a binarization threshold value from pixel data of predetermined pixels included in the local regions 24 and 29. The addition value is calculated, and the binarization threshold value determining device 6 calculates the binarization threshold value TH using the reference value and the addition value.

If the pixel data D of the target pixel 20 is equal to or greater than the binarization threshold value TH, the binarization output device 7 (D ≧ T
H), if the pixel data of the pixel of interest is smaller than the binarization threshold value TH (D <TH) in the binary data of “1” expressing a white pixel (D <TH), the binary value of “0” expressing a black pixel Each is converted into data to generate and output a binary image.

The area setting device 3, the reference value calculation device 4 and the addition value calculation device 5 are appropriately constructed according to the purpose of use and the purpose of use of the binarization processing device.
Four types of embodiments (first embodiment to fourth embodiment) will be described below.

First, in the first embodiment, the binarization threshold value TH is set high for a black background portion such as a character, the binarization threshold value TH is set low for a white background portion, and 2 is set for a halftone portion.
By setting the threshold value TH in the middle, a black background such as characters and a white background are reproduced in a binary image that is faithful and does not show noise, and the halftone part corresponds to the density change. Is.

In the first embodiment, the area setting device 3
Sets the local region 24 shown in FIG. 3, and the reference value calculation device 4 sets the three pixels 21, 22, 22 included in the local region 24.
Using the pixel data A, B, and C of 23, the density level S of the grayscale image in the local area 24 is calculated by the following equation (1).
The reference value T is calculated by the equation (2).

[0026]

[Equation 1]

[0027]

[Equation 2]

The addition value calculating device 5 determines the addition value K according to the magnitude of the density level S. If the density level S is equal to or lower than the lower limit value S1 (S≤S1),
According to the equation (3), if it is larger than the upper limit S2 (S> S2)
If the value is larger than the lower limit value S1 and equal to or less than the upper limit value S2 by the following equation (4) (S1 <S ≦ S2), the additional value K is calculated by the following equation (5).

[0029]

[Equation 3]

[0030]

[Equation 4]

[0031]

[Equation 5]

In the above equation, the lower limit value S1 is assumed to be a thin horizontal line, and the upper limit value S2 is assumed to be a newspaper background, for example. 180 "and S2 are set to" 480 ".

The reference value T is calculated by the reference value calculation device 4 as follows.
Further, when the added value K is calculated by the added value calculation device 5, the binarization threshold value determination device 6 adds the addition value K corresponding to the magnitude of the density level S to the reference value T and binarizes it. The threshold value TH is calculated.

Next, in the second embodiment, a binarization threshold value TH that makes it difficult to pick up a density change in a part where the density change is small, such as a black background part of a character or a white background part of the background, and as in a halftone dot photograph. By setting the binarization threshold value TH which is easy to pick up the density change in the part where the density change is large in the narrow region or the part where the thin line exists, the black background, the white background,
The dots and fine lines of halftone pictures are faithfully reproduced.

The area setting device 3 of the second embodiment is also shown in FIG.
In the case of the second embodiment, the reference value calculation device 4 sets the pixel area D, A, 4 of the four pixels 20, 21, 22, 23 included in the local area 24.
Using B and C, the density level S of the grayscale image in the local area 24 is calculated by the following equation (6), the binarization reference value T is calculated by the equation (2), and the density difference is calculated by the following equation (7). W is calculated respectively.

[0036]

[Equation 6]

[0037]

[Equation 7]

Further, the addition value calculating device 5 determines the addition value K according to the magnitude of the reference value T and the density difference W. If the reference value T is less than or equal to the lower limit value T1 (T≤T1). According to the following equation (8), if the upper limit value T2 or more (T ≧ T
2) According to the following equation (9), if it is larger than the lower limit value T1 and smaller than the upper limit value T2, and the density difference W is not more than the discrimination value W1 (for example, W1 = 32) of the halftone dot area (T1 <T <
T2, W ≦ W1) According to the following equation (10), if it is larger than the lower limit value T1 and smaller than the upper limit value T2, and the density difference W is larger than the discrimination value W1 of the halftone dot area (T1 <T <T2,
W> W1) The addition value K is calculated by the following equation (11). In this case, if the density difference W is equal to or smaller than the discriminant value W1, it is determined that it is not a halftone dot region, and if it is larger than the discriminant value W1, it is determined that it is a halftone dot region.

[0039]

[Equation 8]

[0040]

[Equation 9]

[0041]

[Equation 10]

[0042]

[Equation 11]

In the above equation, the lower limit value T1 is assumed to be a case where the target is a dark area, and the upper limit value S1 is assumed to be a case where the object is a whitish area.
1 is set to "96" and T2 is set to "160".

The reference value T is calculated by the reference value calculating device 4 as follows.
Further, when the added value K is calculated by the added value calculating device 5, the binarization threshold value determining device 6 adds to the reference value T the added value corresponding to the magnitude of the reference value T and the magnitude of the density difference W. The binarization threshold value TH is calculated by adding K.

Next, in the third embodiment, different local areas are set depending on whether the coordinate value i of the pixel of interest 20 is an even number or an odd number, and the pixel data of a predetermined pixel in one of the local areas is used. By setting the binarization threshold by
This is to prevent the generation of a moire pattern due to the dot period of a halftone picture and the sampling period of pixel data.

The area setting device 3 of the third embodiment is shown in FIG.
One of the two types of local areas 24 and 29 shown in FIG.
When the coordinate value i of 0 is an even number, one of the local regions 29
Using the pixel data E, F, G, H of each pixel 25, 26, 27, 28 included in
The density level S of the grayscale image in 9 is calculated, and the target pixel 20
When the coordinate value i of is an odd number, the pixel values D, A, B, and C of the pixels 20, 21, 22, and 23 included in the other local area 24 are used to calculate the local area according to the equation (6). Two
The density level S of the grayscale image in 4 is calculated and the above (2)
The binarization reference value T is calculated by the formula.

[0047]

[Equation 12]

The addition value calculation device 5 determines the addition value K according to the magnitude of the density level S. If the density level S is equal to or lower than the lower limit value S1 (for example, S1 = 180) (S≤ S1) According to the above equation (3), if it is larger than the upper limit value S2 (for example, S2 = 480) (S> S2), the above (4)
If it is larger than the lower limit value S1 and smaller than or equal to the upper limit value S2 according to the formula (S1 <S ≦ 480), the addition value K is calculated according to the formula (5), and the binarization threshold value determination device 6 determines the reference value T. The binarization threshold value TH is calculated by adding the addition value K corresponding to the magnitude of the density level S to.

Next, the fourth embodiment is an improved method for solving the problem of the method according to the third embodiment, that is, the problem that the character image is slightly destroyed. This prevents the occurrence of a moire pattern due to the sampling cycle and the black background, the white background, the dots of the halftone dot photograph, and the fine lines, and prevents the character image from collapsing.

The area setting device 3 of the fourth embodiment is shown in FIG.
One of the two types of local areas 24 and 29 shown in FIG. 2 is selected and set, and the reference value calculation device 4 sets the following (13)
When the density difference W given by the formula is smaller than the discrimination value W2 (for example, W2 = 16) between the halftone dot area and the character area (W <W2) and the coordinate value i of the pixel of interest 20 is an even number, one local Each pixel 25, 26, 27, 28 included in the area 29
Using the pixel data E, F, G, H of, the density level S of the grayscale image in the local area 24 is calculated by the equation (2), and the density difference W is smaller than the discrimination value W2 (W <W2) and When the coordinate value i of the pixel of interest 20 is odd, or when the density difference W is equal to or greater than the determination value W2 (W ≧ W2), the pixels 20, 21, included in the other local region 24,
Using the pixel data D, A, B and C of 22 and 23,
The density level S of the grayscale image in the local area 24 is calculated by the equation (6).
Is calculated, and the binarization reference value T is calculated by the equation (2). In this case, if the density difference W is equal to or larger than the discrimination value W2, it is determined to be a character area, and if it is smaller than the discrimination value W2, it is determined to be a halftone dot area.

[0051]

[Equation 13]

The addition value calculating device 5 determines the addition value K according to the magnitude of the density level S. If the density level S is equal to or lower than the lower limit value S1 (for example, S1 = 180) (S≤ S1) According to the equation (3), if it is larger than the upper limit value S2 (for example, S2 = 480) (S> S2), if it is larger than the lower limit value S1 and not more than the upper limit value S2 according to the equation (4) (S1 <S ≦ S2) The addition value K is calculated by the equation (5), and the binarization threshold value determining device 6 determines the reference value T
2 is obtained by adding the addition value K corresponding to the size of the density level S to
The threshold value TH is calculated.

FIG. 5 shows a flow of the operation of the binarization processing device from step 1 (indicated by "ST1" in the figure) to step 8. First, when a grayscale image is generated by the image input device 1 in step 1, each pixel data of the grayscale image is stored in the image memory 2 on a pixel-by-pixel basis (step 2). In the next step 3, one or two local areas are set on the grayscale image by the area setting device 3, and then in step 4, the reference value T is calculated by the reference value calculation device 4 and the addition value calculation device 5 is set.
The added value K is calculated by (step 4,
5).

In the next step 6, the binarization threshold value determining device 6 adds the addition value K to the reference value T to calculate the binarization threshold value TH, and in the following step 7, the binarization output device 7 Outputs the binarized pixel data of the pixel of interest by the binarized threshold value TH. When the same procedure is executed for all the pixels that make up the grayscale image, step 8 returns "Y
ES ”, and the binarization processing of the grayscale image is completed.

FIG. 6 shows a handy type image scanner 1 to which the binarization processing apparatus according to any one of the above embodiments is applied.
However, the present invention is not limited to the image scanner,
It can also be applied to facsimiles and copiers. In the image scanner of FIG. 6, only the binarization processing device of any one of the embodiments is applied, but the binarization processing device according to all the first to fourth embodiments is implemented, The binarization processing device of any one of the embodiments may be activated by selection.

The image scanner 10 of the illustrated example is for moving the surface of the object 11 and reading a character or the like to perform a binarization process to obtain a binary image. A light emitting diode for irradiating the surface of the object 11 with light, an optical system for forming characters on the irradiation surface on the CCD 12, and the like are incorporated. The grayscale image read by the CCD 12 is sent from the code line 15 to the machine body (not shown) and the binarization process is performed. In the figure, 13 is a see-through window for seeing through the object from above, and 14 is a start button switch for starting reading.

[0057]

According to the first aspect of the invention, since the binarization threshold value is variably set for each pixel using the density information around the pixel of interest, the binarization threshold value is set high in a black background such as a character. By setting the binarization threshold value to a low value in the white background portion of the background and setting the binarization threshold value to an intermediate value in the halftone portion, it is possible to faithfully reproduce the black background such as characters and the white background background. Moreover, the halftone portion can correspond to the density change.

In the invention according to claim 2, since the binarization threshold value is variably set for each pixel by using the density information and density change information around the pixel of interest, a black background portion such as a character or a white background portion of the background. As shown in Fig. 2, it is difficult to pick up the density change in the area where the density change is small, and in the area where the density change is large in a narrow area such as a halftone dot picture or where there is a thin line, the density change is picked up. By setting the binarization threshold values that are easy to set, it is possible to faithfully reproduce the black background, the white background, the dots of the halftone dot photograph, and the thin line.

Further, in the invention according to claim 3, any one of the local regions is selected based on the position of the pixel of interest, and the density information around the pixel of interest in the local region is used to determine 2 for each pixel.
Since the threshold value is variably set, it is possible to prevent the generation of the moire pattern due to the dot period of the halftone picture and the sampling period of the pixel data.

Furthermore, in the invention according to claim 4, any one of the local regions is selected based on the position of the pixel of interest, and the density information around the pixel of interest in the local region and the density change information are used to determine 2 for each pixel. Since the threshold value is variably set, it is possible to prevent the generation of moire patterns due to the dot cycle of halftone pictures and the sampling cycle of pixel data, and to faithfully reproduce the black background, white background, dots of halftone pictures and fine lines. Can be reproduced.

In the invention according to claim 5, since any one of the binarization processing devices described above is used in an image scanner, a facsimile, and a copying machine, there is an effect that an image processing device having excellent characteristics can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of a binarization processing device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a specific example of a data structure of each pixel data stored in an image memory.

FIG. 3 is an explanatory diagram showing local regions set on a grayscale image.

FIG. 4 is an explanatory diagram showing another embodiment of a local area set on a grayscale image.

5 is a flowchart showing a flow of operations of the binarization processing device of FIG. 1. FIG.

FIG. 6 is a perspective view showing the outer appearance of a handy image scanner in which the present invention is implemented.

[Explanation of symbols]

 1 image input device 2 image memory 3 area setting device 4 reference value calculation device 5 addition value calculation device 6 binarization threshold value determination device 7 binarization output device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Noda 10 Odoron-cho, Hanazono-cho, Ukyo-ku, Kyoto

Claims (5)

[Claims] 1. A binarization processing device for binarizing each pixel data of a grayscale image, comprising image input means for generating the grayscale image, and a local area around a pixel of interest on the grayscale image. Area setting means for setting an area; density level extracting means for extracting a density level of a grayscale image in the local area from pixel data of a predetermined pixel included in the local area; and density extracted by the density level extracting means 2 for binarizing the pixel data of the pixel of interest according to the level
Binarization threshold value determining means for determining a binarization threshold value, and binarization processing of pixel data of a target pixel by the binarization threshold value determined by the binarization threshold value determination means 2
A binarization processing device comprising a binarization unit. 2. A binarization processing device for binarizing each pixel data of a grayscale image, comprising image input means for generating the grayscale image, and a local area around a pixel of interest on the grayscale image. Area setting means for setting an area; density level extraction means for extracting a density level of a grayscale image in a local area from pixel data of a predetermined pixel included in the local area; Depending on the density difference calculation means for calculating the density difference between the pixel data and the pixel data of the pixel of interest, the density level extracted by the density level extraction means and the density difference calculated by the density difference calculation means. The binarization threshold value determining means for determining the binarization threshold value for binarizing the pixel data of the pixel of interest, and the binarization threshold value determined by the binarization threshold value determining means Binarize pixel data of pixels 2
A binarization processing device comprising a binarization unit. 3. A binarization processing device for binarizing each pixel data of a grayscale image, the image inputting means for generating the grayscale image, and the peripheral of a target pixel on the grayscale image. Area setting means for setting a local area, density level extraction means for extracting the density level of a grayscale image in each local area from pixel data of predetermined pixels included in each local area, and based on the position of the pixel of interest. Binarization threshold value determination for selecting one of the density levels extracted by the density level extraction means and determining a binarization threshold value for binarizing the pixel data of the pixel of interest according to the density level And binarizing the pixel data of the pixel of interest by the binarizing threshold value determined by the binarizing threshold value determining unit.
A binarization processing device comprising a binarization unit. 4. A binarization processing device for binarizing each pixel data of a grayscale image, wherein an image input means for generating the grayscale image and a periphery of a pixel of interest on the grayscale image are different. Area setting means for setting a local area, density level extraction means for extracting a density level of a grayscale image in each local area from pixel data of a predetermined pixel included in each of the local areas; Density difference calculating means for calculating the density difference between the pixel data of a predetermined pixel and the pixel data of the pixel of interest, and one of the density levels extracted by the density level extracting means is selected based on the position of the pixel of interest. Binarization threshold value deciding means for deciding a binarization threshold value for binarizing the pixel data of the target pixel according to the density level thereof and the density difference calculated by the density difference calculating means. , 2 binarizing the pixel data of the pixel of interest by the binarization threshold determined by said binarizing threshold determining means
A binarization processing device comprising a binarization unit. 5. The binarization processing apparatus according to claim 1, wherein each of the means is provided in any one of an image scanner, a facsimile, and a copying machine.