JP2013068445A - Embossed sheet inspection system and embossed sheet inspection method - Google Patents

Abstract

An embossed sheet inspection system and the like capable of suitably inspecting the appearance and defect of an embossed sheet are provided.
In an embossed sheet inspection system 1, an imaging range 3a of an embossed wallpaper sheet 10 illuminated by an obliquely upper illumination 5 is imaged by a line sensor 3 while conveying the embossed wallpaper sheet 10, and image data 20 is imaged. The data is transmitted to the processing device 7. The image processing device 7 extracts a bright spot and a dark spot from the image data 20 according to a predetermined threshold, calculates the sum of the areas of the bright spot and the dark spot in both end regions in the width direction of the embossed wallpaper sheet 10, When the sum of the areas of the bright spot and the dark spot is different by a predetermined amount or more in the regions at both ends in the width direction of the embossed wallpaper sheet 10, the embossed wallpaper sheet 10 is determined to be defective.
[Selection] Figure 1

Description

  The present invention relates to an embossed sheet inspection system and an embossed sheet inspection method for inspecting the appearance and quality of an embossed sheet.

  One type of wallpaper is an embossed wallpaper sheet that is manufactured by transferring an uneven shape of an embossed plate to a resin layer on a base paper. In such an embossed wallpaper sheet, in order to determine a non-defective product or a defective product, for example, the gloss state at both ends in the width direction is compared under the same illumination.

  If the gloss state differs greatly at both ends in the width direction, it is considered as a defective product. As the interior, embossed wallpaper sheets with the same pattern are often aligned and pasted in the width direction, so if the glossy state is different at both ends in the width direction, the embossed wallpaper sheets may appear on the exterior where they touch each other in the width direction. This is because there is a possibility of giving a sense of incongruity.

  The glossy state of the embossed wallpaper sheet looks different under the same lighting because of the uneven shape formed on the embossed wallpaper sheet. For example, the more convex parts and the larger convex parts appear to be glossy However, in many cases, such an appearance inspection is performed by visual inspection.

  On the other hand, there are known examples in which the glossiness of a sheet-like inspection object is inspected without visual observation, and examples thereof are shown in Patent Document 1 and Patent Document 2, for example. If such a method is applied to an embossed wallpaper sheet, the glossiness can be measured.

JP-A-63-315938 JP 05-322762 A

  However, the glossiness is evaluated from the average value or peak value based on the amount of specularly reflected light received from the inspection range. In the case of embossed wallpaper sheet, since the uneven pattern affects the appearance of the glossy state, for example, even if the glossiness is measured in a certain inspection range, a sufficient difference between a good product and a defective product cannot be obtained, That determination is difficult. As described above, the glossiness measured by the conventional measurement method cannot sufficiently reflect the appearance of the glossy state of the embossed wallpaper sheet.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an embossed sheet inspection system and the like that can suitably perform inspection of the appearance and defect of the embossed sheet.

  According to a first aspect of the invention for achieving the above-described object, an embossing sheet is captured in a predetermined imaging range illuminated by an illuminating device, and image data captured by the imaging device is used. An image processing device that performs a good / bad inspection, and the image processing device extracts a light spot and / or dark spot of the image data, and the extracted light spot An emboss sheet inspection system comprising: a good / defective determination unit that determines whether the embossed sheet is good or bad based on a dark spot.

With such a configuration, it is possible to inspect whether the appearance of the embossed sheet is good or bad based on the bright spot or dark spot of the image obtained by imaging the embossed sheet.
In other words, the embossed sheet has a large number of irregularities, but as described above, the more convex and larger the projection, the more glossy it appears, and vice versa. Then, on the image obtained by imaging the embossed sheet with the above-described embossed sheet inspection system, this convex portion where the illumination light is reflected and the reflected light enters the imaging device becomes a bright point, and the illumination light is blocked by the convex portion Often becomes a dark spot.
Therefore, the bright and dark spots on the image correspond to the glossy appearance of the embossed sheet. By determining whether the embossed sheet is good or bad based on the bright or dark spots, the gloss of the embossed sheet is determined. Inspection that sufficiently reflects the appearance of the state is possible, inspection can be easily performed without visual observation, and there is no variation in determination criteria.

It is desirable that the lighting device illuminates the predetermined imaging range of the embossed sheet from obliquely above.
Thereby, since the unevenness | corrugation of an embossed sheet appears notably as the brightness, the external appearance test | inspection of an embossed sheet can be performed more suitably.

The image processing apparatus further includes a bright spot / dark spot area calculation unit that calculates a sum of areas of the extracted bright spots and / or dark spots in a predetermined region of the image data, It is preferable that the unit determines whether the embossed sheet is good or bad based on the calculated total area of the bright spots and / or dark spots.
In this way, the total area of bright and dark spots in a given area is obtained, and the embossed sheet is judged to be good or bad based on this, thereby checking the difference in the glossy appearance of the embossed sheet. It can be suitably reflected.

The good / bad determination unit determines that the embossed sheet is defective when the sum of the areas of the bright spots and / or dark spots differs by a predetermined amount or more in two predetermined areas of the embossed sheet. Is desirable.
Thereby, it is possible to prevent the appearance defect that the glossy state looks different depending on the region of the embossed sheet.

The two predetermined areas of the embossed sheet are preferably areas corresponding to both ends in the width direction of the embossed sheet.
Thereby, when embossed sheets are used side by side in the width direction, such as wallpaper, it is possible to prevent a sense of incongruity from occurring at a location where the sheets contact each other in the width direction.

It is desirable that the light spot / dark spot extracting unit excludes the light spot and / or dark spot having an area smaller than a predetermined value after extracting the light spot and / or dark spot.
As a result, since it is possible to perform inspection by removing minute bright spots and dark spots that have a small influence on the appearance of the gloss state of the embossed sheet, the difference in the appearance of the gloss state of the embossed sheet is reflected more suitably in the inspection. be able to.

  According to a second aspect of the present invention, the imaging device captures the embossed sheet within a predetermined imaging range illuminated by the illumination device, and the image processing device captures the embossed sheet based on the image data captured by the imaging device. Performing the good / bad inspection step, and the image processing apparatus extracts and extracts the bright and / or dark spots of the image data when the embossed sheet is checked for good / bad. An embossed sheet inspection method comprising: determining whether the embossed sheet is good or defective based on the bright spot and / or dark spot.

It is desirable that the lighting device illuminates the predetermined imaging range of the embossed sheet from obliquely above.
The image processing apparatus calculates a sum of areas of the extracted bright spots and / or dark spots in a predetermined region of the image data when the emboss sheet is inspected for good / bad. When determining whether the sheet is good or bad, it is desirable to determine whether the embossed sheet is good or bad based on the calculated total area of the bright and / or dark spots.
Further, when the image processing apparatus determines whether the embossed sheet is good or bad, the total sum of the areas of the bright spots and / or dark spots differs by a predetermined amount or more between the two predetermined areas of the embossed sheet. In addition, it is desirable to determine that the embossed sheet is defective.
Here, it is desirable that the two predetermined areas of the embossed sheet are areas corresponding to both end portions in the width direction of the embossed sheet.
In addition, it is preferable that the image processing apparatus excludes the light spot and / or dark spot having an area smaller than a predetermined value after extracting the light spot and / or dark spot.

  The second invention is an embossed sheet appearance inspection method by the embossed sheet appearance inspection system of the first invention.

  ADVANTAGE OF THE INVENTION According to this invention, the embossed sheet test | inspection system etc. which can perform suitably the quality inspection of the embossed sheet | seat suitably can be provided.

The figure which shows schematic structure of the embossed sheet inspection system 1 The figure explaining the line sensor 3, the illumination 5, and the embossed wallpaper sheet | seat 10 The figure which shows the hardware constitutions of the image processing apparatus 7 The figure which shows the function structure of the image processing apparatus 7. The figure which shows the flow of an inspection by the embossed sheet inspection system 1 The figure which shows the example of the image data 20 The figure which shows the example of the image data 20 The figure which shows the example of the image data 20 The figure which shows the example of the image data 20

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, with reference to FIG. 1, the structure of the embossed sheet test | inspection system 1 of embodiment of this invention is demonstrated.

  The embossed sheet inspection system 1 is for inspecting the appearance and defect of the embossed wallpaper sheet 10 (embossed sheet), and includes a line sensor 3, an illumination 5, an image processing device 7 and the like as shown in FIG. Further, the imaging range 3 a by the line sensor 3 of the line sensor 3, the illumination 5, and the embossed wallpaper sheet 10 is inside the dark box 8.

As shown in FIG. 2, the embossed wallpaper sheet 10 has a convex portion 10a and a concave portion 10b on the surface.
The embossed wallpaper sheet 10 is conveyed in a conveying direction indicated by an arrow in FIG. 1 by a conveying means (not shown) such as a conveying roller, and in the rectangular imaging range 3 a set over the entire width direction of the embossed wallpaper sheet 10. The image is taken by the line sensor 3.

  The line sensor 3 is an imaging device that images the embossed wallpaper sheet 10, and is provided above the imaging range 3 a of the embossed wallpaper sheet 10 at a planar position corresponding to the center in the width direction of the embossed wallpaper sheet 10. Image data of the entire embossed wallpaper sheet 10 is obtained by performing imaging in the imaging range 3 a while conveying the embossed wallpaper sheet 10. In addition, the imaging device should just acquire the image of the embossed wallpaper sheet | seat 10, and it can also use an area sensor etc. instead of the line sensor 3. FIG.

  The illumination 5 is provided obliquely above the imaging range 3a of the embossed wallpaper sheet 10 and illuminates the imaging range 3a from diagonally above. The light source is not particularly limited, and a fluorescent lamp or an LED lamp can be used.

Illumination by the illumination 5 causes light and darkness due to the unevenness in the imaging range 3 a of the embossed wallpaper sheet 10.
That is, the convex portion 10 a of the embossed wallpaper sheet 10 shown in FIG. 2 receives light from the illumination 5, and the reflected light from the convex portion 10 a enters the line sensor 3. In many cases, the reflected portion of the illumination light on the convex portion 10a becomes a bright spot on the image captured by the line sensor 3. On the other hand, in the recessed part 10b, the location where the light from illumination is interrupted | blocked by the convex part 10a increases. Such a location often becomes a dark spot on an image captured by the line sensor 3.

  In the present embodiment, in order to emphasize the brightness and darkness of the embossed wallpaper sheet 10, the illumination 5 preferably has the center of the imaging range 3 a and the illumination 5 on the surface in the normal direction of the embossed wallpaper sheet 10 shown in FIG. 2. An angle α formed by the connecting direction and the normal direction of the embossed wallpaper sheet 10 is provided so as to exceed 30 °. On the other hand, the line sensor 3 is preferably provided such that the angle θ formed by the direction connecting the center of the imaging range 3a and the line sensor 3 and the normal direction of the embossed wallpaper sheet 10 is in the range of 0 to 30 °. .

  The image processing apparatus 7 is connected to the line sensor 3 and acquires image data obtained by imaging the embossed wallpaper sheet 10 from the line sensor 3. Based on this, the image processing apparatus 7 determines whether the appearance of the embossed wallpaper sheet 10 is good or bad by processing described later. To do.

  FIG. 3 is a block diagram illustrating a hardware configuration of the image processing apparatus 7. As shown in the figure, the image processing apparatus 7 includes a control unit 11, a storage unit 12, a media input / output unit 13, a communication control unit 14, an input unit 15, a display unit 16, a peripheral device I / F unit 17, and the like. 18 is connected through 18.

The control unit 11 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like.
The CPU calls a program stored in the storage unit 12, ROM, storage medium, etc. to a work memory area on the RAM and executes it, drives and controls each device connected via the bus 18, and the image processing device 7 The process to be described later is realized. The ROM is a non-volatile memory and permanently stores programs such as a boot program and BIOS, data, and the like. The RAM is a volatile memory, and temporarily stores programs, data, and the like loaded from the storage unit 12, ROM, storage medium, and the like, and includes a work area used by the control unit 11 to perform each process.

The storage unit 12 is an HDD (hard disk drive) or the like, and stores a program executed by the control unit 11, data necessary for program execution, an OS (operating system), and the like. As for the program, a control program corresponding to the OS and an application program for executing processing to be described later are stored.
Each of these program codes is read by the control unit 11 as necessary, transferred to the RAM, and read and executed by the CPU.

The media input / output unit 13 (drive device) inputs / outputs data, for example, media such as a CD drive (-ROM, -R, -RW, etc.), DVD drive (-ROM, -R, -RW, etc.) Has input / output devices.
The communication control unit 14 includes a communication control device, a communication port, and the like, and is a communication interface that mediates communication with other devices, and performs communication control with other devices via a network. The network may be wired or wireless.

The input unit 15 inputs data and includes, for example, a keyboard, a pointing device such as a mouse, and an input device such as a numeric keypad.
The display unit 16 includes a display device such as a CRT monitor and a liquid crystal panel, and a logic circuit for realizing a display function in cooperation with the display device.

The peripheral device I / F (interface) unit 17 is a port for connecting a peripheral device, and performs data transmission / reception with the peripheral device via the peripheral device I / F unit 17. The peripheral device I / F unit 17 is configured by a USB or the like, and usually includes a plurality of peripheral devices I / F. The connection form with the peripheral device may be wired or wireless.
The bus 18 is a path that mediates transmission / reception of control signals, data signals, and the like between the devices.

FIG. 4 is a diagram illustrating a functional configuration of the image processing apparatus 7.
As shown in FIG. 4, the image processing apparatus 7 includes an image data acquisition unit 71, a bright / dark spot extraction unit 73, a bright / dark spot area calculation unit 75, a good / bad determination unit 77, a result output unit 79, and the like. The image data 20 is stored in the storage unit 12.

In the image data acquisition unit 71, the control unit 11 of the image processing device 7 acquires the image data 20 obtained by capturing the embossed wallpaper sheet 10 with the line sensor 3 and stores it in the storage unit 12.
The bright spot / dark spot extraction unit 73 is a unit in which the control unit 11 of the image processing apparatus 7 performs multi-value processing based on a predetermined threshold value on the image data 20 to extract a bright spot and a dark spot.
The bright spot / dark spot area calculation unit 75 is used by the control unit 11 of the image processing device 7 to calculate the areas of the extracted bright spots and dark spots.
The good / bad determination unit 77 is for the control unit 11 of the image processing device 7 to determine whether the embossed wallpaper sheet 10 is good or bad from the areas of the bright and dark spots calculated above.
The result output unit 79 is for the control unit 11 of the image processing apparatus 7 to display and output the result of the determination of good / bad on the display unit 16 or the like.

  Next, the flow of processing in the embossed sheet inspection system 1 will be described with reference to FIG.

  In the embossed sheet inspection system 1, first, the embossed wallpaper sheet 10 is imaged by conveying the embossed wallpaper sheet 10 and imaging the imaging range 3a with the line sensor 3 (S101).

The line sensor 3 transmits image data 20 obtained by capturing the embossed wallpaper sheet 10 to the image processing device 7. The control unit 11 of the image processing apparatus 7 receives and acquires the image data 20, and stores it in the storage unit 12 (S102).
An example of the image data 20 is shown in FIG. 6 shows left and right predetermined areas corresponding to both ends of the embossed wallpaper sheet 10 in the width direction in the image data 20 of the entire embossed wallpaper sheet 10. The same applies to FIGS. 7 to 9 described later.

  Next, the control unit 11 of the image processing apparatus 7 performs local brightness change correction processing on the image data 20 (S103).

  In the imaging range 3a, the amount of light incident on the line sensor 3 from the imaging range 3a decreases slightly on average as it goes toward both ends of the embossed wallpaper sheet 10 in the width direction. Accordingly, in S103, the average luminance (pixel value) is slightly increased as a whole toward the both ends of the embossed wallpaper sheet 10 in the width direction in the image data 20 in response to the change in the light amount. Make corrections. An example of the image data 20 is shown in FIG.

  Subsequently, the control unit 11 of the image processing apparatus 7 extracts a bright spot and a dark spot from the image data 20 (S104).

  In S104, the image data 20 is multi-valued using two predetermined threshold values, and a portion having a higher luminance than the higher threshold is extracted as a bright point, and a portion having a lower luminance than the lower threshold is used as a dark point. Extract. This threshold value is set to an appropriate value in advance and stored in the storage unit 12 or the like. In the image data 20, FIG. 8 shows an example in which a bright point is displayed in white and a dark point is displayed in black.

  Thereafter, the control unit 11 of the image processing apparatus 7 performs a process of excluding minute points with respect to the bright and dark points in the image data 20 (S105).

In S105, the control unit 11 of the image processing apparatus 7 performs labeling of the individual bright spot and dark spot areas extracted in S104, calculates the area (number of pixels), and brightens those that are smaller than a predetermined value. Exclude from points or dark spots. This predetermined value is also set to an appropriate value in advance as described above, and is stored in the storage unit 12 or the like. FIG. 9 shows a state where small bright spots and dark spots are excluded in this way.
Note that instead of the above processing, for each bright point and dark point, a minute point may be eliminated and excluded by performing a contraction process that reduces the pixels of the outer peripheral portion by a predetermined width.

  Then, the control unit 11 of the image processing device 7 calculates the sum of the areas of the bright and dark spots after excluding the minute dots (S106), and based on this value, the non-defective / unusable embossed wallpaper sheet 10 is calculated. A non-defective product is determined (S107).

In S <b> 106, the sum of the areas of the bright and dark spots is calculated for two predetermined regions (left and right images in FIG. 9) corresponding to both ends in the width direction of the embossed wallpaper sheet 10 in the image data 20.
In S107, if the sum of the areas of the bright and dark spots is different by a predetermined amount or more between the two regions, it is determined that the product is defective.
The area to be compared and the above-mentioned predetermined amount are determined in advance in the same manner as described above and stored in the storage unit 12 or the like.

  The state of the bright spot and the dark spot depends on the convex part of the embossed wallpaper sheet 10 as described above, and the total area of the bright spot and the dark spot is larger as the convex part is larger and the convex part is larger. In such a case, the embossed wallpaper sheet 10 has a glossy appearance. On the other hand, when the number of convex portions is small and the convex portions are small, the opposite is true. Therefore, if the sum of the areas of the bright spots and the dark spots is greatly different between the two regions, the glossy state is greatly different. In such a case, the embossed wallpaper sheet 10 is determined to be defective in appearance. I do.

Thereafter, the image processing apparatus 7 outputs the result of determination of good / bad as an inspection result on the display unit 16 (S108), and the process in the embossed sheet inspection system 1 is terminated.
Note that an alarm device may be connected to the image processing device 7 so that an alarm is issued when it is determined to be defective so as to notify the operator that a defect has occurred. As the alarm device, for example, a device that gives a warning by lighting a lamp, a device that gives a warning by sound, or a device that displays that a defect has occurred on a monitor or the like can be used.

As described above, according to the present embodiment, it is possible to determine whether the appearance of the embossed wallpaper sheet 10 is good or bad based on the bright spot or dark spot on the image data 20 obtained by capturing the embossed wallpaper sheet 10.
As described above, the bright and dark points on the image data 20 correspond to the appearance of the glossy state of the embossed wallpaper sheet 10, so whether the embossed wallpaper sheet 10 is good or bad is determined based on the bright or dark points. By performing the determination, the determination result sufficiently reflects the appearance of the glossy state of the embossed wallpaper sheet 10, the determination can be easily performed without visual observation, and there is no variation in the determination criteria.

  Moreover, since the illumination 5 illuminates the imaging range 3a of the embossed wallpaper sheet 10 from obliquely above, the unevenness of the embossed wallpaper sheet 10 appears prominently as light and dark, and the appearance of the embossed wallpaper sheet 10 is more suitably inspected. Can do.

  Moreover, in this embodiment, the sum total of the area of a bright spot and a dark spot is calculated in two area | regions of the both ends of the width direction of the embossed wallpaper sheet 10, and when this differs by a predetermined amount, the embossed wallpaper sheet 10 is unsatisfactory. Therefore, the difference in appearance of the glossy state of the embossed wallpaper sheet 10 can be suitably reflected in the determination result, and the appearance defect that the glossy state looks different due to the difference in the area of the embossed wallpaper sheet 10 can be prevented. Can do. In particular, in the present embodiment, both end portions in the width direction of the embossed wallpaper sheet 10 are compared. When the embossed wallpaper sheets 10 are arranged side by side in the width direction and used in an interior or the like, the sheets touch each other in the width direction. It is possible to prevent a sense of incongruity from occurring at a location.

In this embodiment, the sum of the areas of the bright spots and the dark spots is calculated and used for the determination, but in addition, the same determination is made using only the sum of the areas of the bright spots or the sum of the areas of the dark spots. It is also possible to perform.
In addition to the area, the number of bright spots and dark spots can be calculated and used for determination. For example, the embossed wallpaper sheet can be determined as a defective product when the number of the two regions differs by a predetermined amount or more. Similarly to the above, in this case, the determination can be made using only the number of bright points or dark points.

Moreover, the area | region to compare is also defined according to the objective, and is not restricted to the both ends of the width direction of the embossed wallpaper sheet 10. FIG.
In addition, it is possible to determine good / bad based on the sum of areas of bright spots and dark spots in one area instead of comparing areas. For example, it is possible to determine a defective product when a reference value is provided in advance and the reference value is greater than or less than the reference value.

  Moreover, in this embodiment, since the said determination is performed by removing minute bright spots and dark spots that have a small influence on the appearance of the glossy state of the embossed wallpaper sheet 10, the determination result is the difference in the glossy state of the embossed wallpaper sheet 10. It will be more in line with However, it is possible to leave out the minute points.

As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.
For example, in this embodiment, the inspection target of the embossed sheet inspection system 1 is an embossed wallpaper sheet. However, the present invention is not limited to wallpaper and can be similarly applied to any embossed sheet having unevenness.

DESCRIPTION OF SYMBOLS 1 ......... Embossed sheet inspection system 3 ......... Line sensor 3a ......... Image pickup range 5 ......... Lighting 7 ...... Image processing device 10 ......... Embossed wallpaper sheet 20 ......... Image data 71 ......... Image Data acquisition unit 73... Bright spot / dark spot extraction unit 75... Bright spot / dark spot area calculation unit 77... Good / bad judgment unit 79.

Claims (12)

An imaging device for imaging the embossed sheet in a predetermined imaging range illuminated by the lighting device;
An image processing device for inspecting the embossed sheet for good / bad based on image data captured by the imaging device;
Comprising
The image processing apparatus includes:
A light spot / dark spot extracting unit for extracting a light spot and / or a dark spot of the image data;
Based on the extracted bright spot and / or dark spot, a good / bad determination unit for determining good / bad of the embossed sheet;
An embossed sheet inspection system comprising:   The embossed sheet inspection system according to claim 1, wherein the illumination device illuminates the predetermined imaging range of the embossed sheet from obliquely above. The image processing apparatus includes:
A light spot / dark spot area calculating unit for calculating a sum of areas of the extracted bright spots and / or dark spots in a predetermined region of the image data;
The good / bad determination unit
The embossed sheet inspection system according to claim 1, wherein the embossed sheet is determined to be good or defective based on the calculated total area of the bright spots and / or dark spots.   The good / bad determination unit determines that the embossed sheet is defective when the sum of the areas of the bright spots and / or dark spots differs by a predetermined amount or more in two predetermined areas of the embossed sheet. The embossed sheet inspection system according to claim 3.   The embossed sheet inspection system according to claim 4, wherein the two predetermined areas of the embossed sheet are areas corresponding to both ends of the embossed sheet in the width direction.   The bright point / dark spot extracting unit, after extracting the bright spot and / or dark spot, excludes the bright spot and / or dark spot having an area smaller than a predetermined value. 6. The embossed sheet inspection system according to any one of items 5. The imaging device imaging the embossed sheet in a predetermined imaging range illuminated by the illumination device; and
An image processing device, based on the image data captured by the imaging device, performing a good / bad inspection of the embossed sheet;
Run
The image processing apparatus, when performing a good / bad inspection of the embossed sheet,
Extracting bright and / or dark spots of the image data;
An embossed sheet inspection method comprising: determining whether the embossed sheet is good or bad based on the extracted bright spot and / or dark spot.   8. The embossed sheet inspection method according to claim 7, wherein the illumination device illuminates the predetermined imaging range of the embossed sheet from obliquely above. The image processing apparatus, when performing a good / bad inspection of the embossed sheet,
Calculating the sum of the areas of the extracted bright spots and / or dark spots in a predetermined region of the image data;
8. The quality of the embossed sheet is determined based on the calculated total area of the bright and / or dark spots when the quality of the embossed sheet is determined. Or the embossed sheet inspection method of Claim 8.   When determining whether the embossed sheet is good or defective, the image processing apparatus, when the sum of the areas of the bright spots and / or dark spots is different by a predetermined amount or more in two predetermined areas of the embossed sheet, The embossed sheet inspection method according to claim 9, wherein the embossed sheet is determined to be defective.   The embossed sheet inspection method according to claim 10, wherein the two predetermined areas of the embossed sheet are areas corresponding to both ends in the width direction of the embossed sheet.   12. The image processing apparatus according to claim 7, wherein after the bright point and / or dark spot is extracted, the bright point and / or dark spot having an area smaller than a predetermined value is excluded. The embossed sheet inspection method according to crab.