Tile diagnostic system, tile diagnostic method and tile diagnosis program

Abstract

To achieve accurate diagnosis of tile defects from a thermal image.SOLUTION: A tile diagnostic system comprises: an acquisition part configured to image a diagnosis target tile through a polarization lens to obtain a thermal image and a visible light image obtained by imaging the diagnosis target tile; a correction part configured to correct a pixel value of each pixel of the thermal image according to lightness of the corresponding pixel of the visible light image; and a diagnosis part configured to diagnose abnormalities in the diagnosis target tile on the basis of the corrected thermal image.SELECTED DRAWING: Figure 18

Description

[Technical Field]

[0001] The disclosed technology relates to a tile diagnostic device, a tile diagnostic method, and a tile diagnostic program. [Background technology]

[0002] Patent Document 1 describes a method for correcting the positional deviation between an infrared image and a corrected visible light image by using the brightness information of the acquired infrared image and the saturation information and hue information of the corrected visible light image in order to correct the image and remove disturbances.

[0003] Patent Document 2 describes a method in which temperature distribution fluctuations occurring in a structure are measured as thermal images using an infrared camera, relative stress fluctuations are grasped based on this temperature distribution fluctuation, the absolute value of stress at each point is measured from strain information at each point within the field of view obtained by applying digital image correlation to the thermal image, the position of the thermal image data is corrected using the measured absolute value of stress, and the stress fluctuation distribution is grasped from the corrected thermal image data. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-103906 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-232998 Summary of the Invention [Problem to be solved by the invention]

[0005] The prior art leaves room for improvement when diagnosing tile anomalies using thermal images.

[0006] The disclosed technology has been made in consideration of the above points, and aims to provide a tile diagnosis device, a tile diagnosis method, and a tile diagnosis program that can accurately diagnose tile abnormalities from thermal images. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a tile diagnosis device that includes an acquisition unit that acquires a thermal image of a tile to be diagnosed taken through a polarized lens and also acquires a visible light image of the tile to be diagnosed, a correction unit that corrects the pixel value of each pixel of the thermal image according to the brightness of the corresponding pixel in the visible light image, and a diagnosis unit that diagnoses abnormalities in the tile to be diagnosed based on the corrected thermal image.

[0008] A second aspect of the present disclosure is a tile diagnosis method, in which an acquisition unit acquires a thermal image of a tile to be diagnosed taken through a polarized lens and also acquires a visible light image of the tile to be diagnosed, a correction unit corrects the pixel value of each pixel of the thermal image according to the brightness of the corresponding pixel in the visible light image, and a diagnosis unit diagnoses abnormalities in the tile to be diagnosed based on the corrected thermal image.

[0009] A third aspect of the present disclosure is a tile diagnosis program that causes a computer to acquire a thermal image of a tile to be diagnosed taken through a polarized lens, and also acquire a visible light image of the tile to be diagnosed, correct the pixel value of each pixel of the thermal image according to the brightness of the corresponding pixel in the visible light image, and diagnose abnormalities in the tile to be diagnosed based on the corrected thermal image. [Effects of the Invention]

[0010] According to the disclosed technology, tile abnormalities can be accurately diagnosed from thermal images. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1A is a diagram showing an example of a visible light image of an exterior wall tile, and FIG. 1B is a diagram showing an example of a thermal image of an exterior wall tile. [Figure 2] FIG. 2 is a diagram for explaining reflection, absorption, and transmission of light. [Figure 3]FIG. 1 is a diagram for explaining an example of a test specimen. [Figure 4] This is an image showing how a test specimen is placed so that human body heat is reflected by the tile surface and photographed with an infrared camera. [Figure 5] (A) A figure showing an example of a visible light image taken of a white bright exterior wall tile, (B) A figure showing an example of a thermal image including thermal reflection taken of a white bright exterior wall tile, (C) A figure showing an example of an analysis image obtained by distinguishing the thermal image of Figure 5(B), (D) A figure showing an example of a thermal image taken after removing the thermal reflection of the white bright exterior wall tile, and (E) A figure showing an example of an analysis image obtained by distinguishing the thermal image of Figure 5(D). [Figure 6] (A) A figure showing an example of a visible light image taken of a black matte exterior wall tile, (B) A figure showing an example of a thermal image including thermal reflection taken of a black matte exterior wall tile, (C) A figure showing an example of an analysis image obtained by distinguishing the thermal image of Figure 6(B), (D) A figure showing an example of a thermal image taken after removing the thermal reflection of the black matte exterior wall tile, and (E) A figure showing an example of an analysis image obtained by distinguishing the thermal image of Figure 6(D). [Figure 7] This is an image diagram showing tiles being placed and infrared camera images being taken with and without sky temperature heat reflection. [Figure 8] 10 is a graph showing the results of comparing the difference between the detected temperature with sky reflection and the detected temperature without sky reflection on the surface of a tile with the brightness of the tile. [Figure 9] (A) A figure showing an example of a thermal image of a typical example of deformation in exterior wall tiles, (B) A figure showing an example of an analysis image in which the deformed part has been extracted, (C) A figure showing an example of a visible light image of a typical example of deformation in exterior wall tiles, and (D) An enlarged view of a visible light image of a typical example of deformation in exterior wall tiles. [Figure 10] (A) A figure showing an example of a thermal image including thermal reflection taken using a standard lens, (B) an analysis image in which the deformed area has been extracted from the thermal image of Figure 10(A), (C) a figure showing an example of a thermal image in which the thermal reflection has been removed taken using a polarized lens, and (D) an analysis image in which the deformed area has been extracted from the thermal image of Figure 10(C). [Figure 11]FIG. 1A is a diagram showing an example of a visible light image taken of a black area and a white area of a tile, and FIG. 1B is a diagram showing an example of a thermal image taken of a black area and a white area of a tile. [Figure 12] FIG. 10 is a scatter plot showing the brightness of the visible light image and the detected temperature of the thermal image for each pixel. [Figure 13] (A) A figure showing an example of a visible light image of the black and white areas of a tile, (B) A figure showing an example of a thermal image of the black and white areas of a tile after correcting for the temperature difference, and (C) A figure showing an example of an analysis image in which deformations are extracted from Figure 13(B). [Figure 14] (A) A figure showing an example of a thermal image of exterior wall tiles including joints, (B) a figure showing an example of an analysis image in which the temperature difference has been extracted, and (C) a figure showing an example of an analysis image in which the temperature difference has been extracted. [Figure 15] FIG. 10A is a diagram showing a visible light image taken of a location where no abnormal noise is generated, and FIG. 10B is a diagram showing an example of an analysis image in which a temperature difference has been extracted. [Figure 16] 10 is a diagram for explaining that a portion where the heat reflection direction is different becomes a portion where heat reflection is not removed. [Figure 17] FIG. 2 is a block diagram showing the hardware configuration of the tile diagnosis device of the present embodiment. [Figure 18] FIG. 2 is a block diagram showing an example of a functional configuration of a tile diagnosis device. [Figure 19] FIG. 2 is a diagram for explaining a thermal imaging camera and a visible light imaging camera connected to the tile diagnosis device. [Figure 20] 3 is a flowchart showing the flow of tile diagnosis processing by the tile diagnosis device 10. DETAILED DESCRIPTION OF THE INVENTION

[0012] An example of an embodiment of the disclosed technology will be described below with reference to the drawings. Note that the same or equivalent components and parts in each drawing are given the same reference numerals. Also, the dimensional proportions in the drawings are exaggerated for the convenience of explanation and may differ from the actual proportions.

[0013] <Outline of this embodiment> Among the methods for inspecting exterior wall tiles, infrared thermography (hereinafter referred to as infrared inspection) does not require scaffolding and can measure large areas of wall surfaces in a short time. However, there are thermal conditions under which infrared inspections can be applied, and there have been concerns about the possibility of misdiagnosis due to heat reflection in particular.

[0014] Figure 1(A) shows an example of a visible light image of an exterior wall tile. Figure 1(B) shows an example of a thermal image of an exterior wall tile. As shown in Figure 1(A), heat reflection is influenced by the color of the surface being investigated, and as shown in Figure 1(B), the phenomenon occurs in which the detected temperature differs depending on the color of the exterior wall tile.

[0015] Infrared inspection is a method of detecting temperature differences that occur in deformed areas, but if the detected temperatures differ depending on the color of the tile, it becomes difficult to identify the deformed areas.

[0016] Here, it has been confirmed that infrared cameras using polarized lenses are effective in reducing misdiagnosis by eliminating heat reflection in bridge concrete. Therefore, in this embodiment, a trial survey of tile exterior walls using polarized lenses was conducted, and an advanced infrared diagnostic technology was realized that focuses on the brightness of the tiles.

[0017] (Pre-verification) (Verification using test specimens) When light enters an object, it is reflected (ρ), absorbed (α), and transmitted (τ) as shown in Figure 2, and equation (1) holds true based on the law of conservation of energy.

[0018] ρ+α+τ=1···Eq.(1)

[0019] If transmission (τ) is set to 0, reflection (ρ) and absorption (α) are opposites, and objects that absorb light, such as black objects, are less likely to reflect light and are more likely to heat up. Therefore, when conducting infrared surveys, it is important to pay attention to the color of the object being surveyed. Therefore, using the six types of tiles listed in Table 1, we created a test specimen as shown in Figure 3 to verify the thermal reflection characteristics of the tiles and the effectiveness of polarized lenses in eliminating thermal reflection. A floating area was created in the center of the test specimen due to surface peeling of the tile, and an evaluation was conducted to determine whether the temperature difference caused by the floating area could be detected using an infrared camera. Figure 3 shows an example of a test specimen in which a loose tile was created in the center of the tile, resulting in a floating tile.

[0020] [Table 1]

[0021] As shown in Figure 4, the test specimen was placed so that human body heat would be reflected by the tile surface, and an infrared camera was used to photograph the specimen. The temperature difference was extracted from the thermal image, and the detection status of the lifting was evaluated from the analysis image.

[0022] Figure 5(A) shows an example of a visible light image of white bright exterior wall tiles. Figures 5(B) and (D) show examples of thermal images of white bright exterior wall tiles. Figures 5(C) and (E) show examples of analytical images in which loose tiles have been identified by extracting temperature differences.

[0023] Of the six types, "White Bright" had the highest degree of heat reflection, and with standard lenses, the heat reflection from humans interfered and it was impossible to distinguish the loose tiles (see Figures 5(B) and (C)). However, by using polarized lenses, the heat reflection was eliminated and the loose tiles could be distinguished (see Figures 5(D) and (E)).

[0024] Figure 6(A) shows an example of a visible light image of a black matte exterior wall tile. Figures 6(B) and (D) show examples of thermal images of black matte exterior wall tiles. Figures 6(C) and (E) show examples of analytical images in which loose tiles have been identified by extracting temperature differences.

[0025] Of the six types, the "black matte" had the least degree of heat reflection, with only slight heat reflection noise being present with the standard lens, making it possible to identify loose tiles (see Figures 6(B) and (C)). Furthermore, by using polarized lenses, heat reflection was completely eliminated, making it possible to more clearly identify loose tiles (see Figures 6(D) and (E)). These results demonstrate that by using polarized lenses, heat reflection can be eliminated and loose tiles hidden in exterior tile walls can be detected by temperature differences.

[0026] (tile color and heat reflectance properties) The tiles shown in Table 1 were used to verify the thermal reflection characteristics of each type. The tiles were arranged as shown in Figure 7, and infrared camera images were taken with and without the thermal reflection of the sky temperature (hereafter referred to as sky reflection), and the detected temperatures of the tile surfaces were compared. When sky reflection is present, the detected temperature is detected as lower than it should be due to the influence of the cold sky. In this case, we verified whether there was a difference in the influence of heat reflection between the types of tile.

[0027] Regarding the detected temperature of the tile surface, we compared the difference between the detected temperature without sky reflection and the detected temperature with sky reflection (hereafter referred to as the differential temperature) with the tile lightness (see Figure 8). The closer the color is to white, the higher the lightness and the larger the differential temperature value, which indicates a greater influence of sky reflection.

[0028] White has little light absorption but large reflection, confirming the relationship in formula (1) above. Also, the glossy "bright white" is slightly lower in brightness than the non-glossy "matt white," but the effect of sky reflection is large.

[0029] From the above results, it was found that the effect of heat reflection varies depending on the color (brightness) of tiles, and that glossy tiles are more susceptible to heat reflection.

[0030] (Trial survey of exterior tile walls) (Survey Overview) A trial survey was conducted at a building in Takamatsu City. The building surveyed had white tiles on the walls and faced south, so there was concern about sunlight reflection during the day. Therefore, polarized lenses were used to eliminate heat reflection and thermal images were taken. For comparative verification, images were also taken with a standard lens. A test specimen (white mat) created in advance verification was placed on site, and thermal images were taken at times when the floating parts could be extracted.

[0031] (Survey results) Figure 9 shows a typical example of deformation detected by infrared inspection. Figure 9(A) shows an example of a thermal image taken of a typical example of deformation in exterior wall tiles. Figure 9(B) shows an example of an analysis image in which the deformation area has been extracted by temperature difference extraction. Figure 9(C) shows an example of a visible light image taken of a typical example of deformation in exterior wall tiles. Figure 9(D) shows an enlarged view of Figure 9(C). In this location, close-up tapping after the infrared inspection confirmed that the tiles had peeled off. In this case, abnormal sounds were confirmed in seven of the nine locations that were close-up tapped after the infrared inspection, giving a hit rate of 77.8%.

[0032] (Effect of polarized lenses) Figure 10 shows a comparison of images taken with a standard lens and a polarized lens. Figure 10(A) shows an example of a thermal image taken with a standard lens. Figure 10(B) shows an example of an analysis image in which deformed parts of exterior wall tiles have been extracted by temperature difference extraction. Figure 10(C) shows an example of a thermal image taken with a polarized lens. Figure 10(D) shows an example of an analysis image in which deformed parts of exterior wall tiles have been extracted by temperature difference extraction.

[0033] With standard lenses (see Figures 10(A) and (B)), sunlight is reflected, causing significant temperature variations and making it difficult to detect abnormalities. With polarized lenses (see Figures 10(C) and (D)), sunlight reflection is eliminated, making it possible to clearly detect abnormalities.

[0034] Even if infrared inspections are carried out in the proper manner, it is difficult to avoid misdiagnosis with standard lenses, and we believe that the application of polarized lenses is highly effective.

[0035] (Points to note when inspecting exterior wall tiles) (Temperature difference due to different tile colors) As shown in equation (1) and Figure 8, the color of the tile affects the temperature detected by the infrared camera. When the black area (hereafter referred to as Area A) and the white area (hereafter referred to as Area B) of the tile, as in the visible light image in Figure 11(A), are photographed with an infrared camera, the resulting thermal image is shown in Figure 11(B). Due to the color difference, Area A is detected as a high temperature and Area B as a low temperature. In infrared surveys, which aim to detect temperature differences in abnormalities, color differences make detecting abnormalities difficult. In this case, temperature correction using the brightness obtained from the visible image is effective. The brightness of the visible light image (Figure 11(A)) and the detected temperature of the thermal image (Figure 11(B)) are plotted pixel by pixel in a scatter plot like the one shown in Figure 12. Note that the pixels in the joints are excluded, and only the pixels in the tile are used. Looking at the data distribution, Area A is grouped into Group A, and Area B into Group B, resulting in an approximate straight line with a high contribution rate. When the gradient of this approximation line (-2.0254) is used as a correction coefficient and image processing is performed, the thermal image shown in Figure 13(B) is obtained. Areas A and B are at roughly the same temperature, and the analysis image obtained by extracting the temperature difference (Figure 13(C)) shows that the temperature difference confirmed in the center of the image has been extracted. If the survey is conducted at night when there is no sunlight, the tile color does not have a significant impact, but if daytime surveys are considered the norm, tile color must be taken into consideration when making a diagnosis.

[0036] (Temperature difference between tile and joint) Figure 14(A) shows an example of a thermal image of exterior wall tiles including joints. Figure 14(B) shows an example of an analysis image in which the temperature difference has been extracted. Figure 14(C) shows an example of an analysis image in which the temperature difference has been extracted.

[0037] Because the temperatures of the tile and joint areas are different, when a temperature difference is detected in the analysis image, it appears as if there is a defect in the joint area (Fig. 14(B)). In other words, the joint area is extracted along with the defect area. In such cases, it is necessary to reconsider the maximum temperature difference to be detected (hereafter referred to as the temperature difference threshold). In this case, by setting the temperature difference threshold from 1.0°C to 0.4°C, unnecessary temperature difference detection (misdiagnosis) in the joint area was prevented (Fig. 14(C)). In other words, it was possible to extract only the defect area without extracting the joint area.

[0038] (Temperature difference due to differences in heat reflection direction) Of the nine locations that were examined by close tapping after the infrared inspection, two locations produced no abnormal noise. Representative images of the locations with no abnormal noise are shown in Figures 15(A) and (B). Figure 15(A) shows a visible light image taken of the location with no abnormal noise. Figure 15(B) shows an example of an analysis image in which the temperature difference has been extracted.

[0039] It is speculated that the reason for the temperature difference occurring despite the absence of abnormal noise is that some tiles were tilted relative to the surrounding area. This means that the heat reflection direction is different in only some areas. If the heat reflection direction is consistent, the heat reflection can be uniformly removed with a polarized lens, but areas with a different heat reflection direction are areas where the heat reflection is not removed (see Figure 16). This is thought to be why the temperature difference occurred in areas where there was no abnormal noise. Note that the infrared inspection system currently being developed by the applicant calculates the temperature value after removing heat reflection for each pixel in the thermal image, and obtains analysis results that remove heat reflection from all directions, so it is believed that this system can also solve these issues.

[0040] As described above, in this embodiment, a thermal image is taken using a polarized lens, and image processing is performed to correct brightness differences between tiles, thereby improving infrared diagnostic techniques for exterior wall tiles.

[0041] <Configuration of the tile diagnosis device according to this embodiment> FIG. 17 is a block diagram showing the hardware configuration of the tile diagnosis device 10 of this embodiment.

[0042] 17, the tile diagnostic device 10 includes a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, a storage 14, an input unit 15, a display unit 16, and a communication interface (I / F) 17. Each component is connected to each other via a bus 19 so as to be able to communicate with each other.

[0043] The CPU 11 is a central processing unit that executes various programs and controls each component. That is, the CPU 11 reads programs from the ROM 12 or storage 14 and executes the programs using the RAM 13 as a work area. The CPU 11 controls the above components and performs various arithmetic processing in accordance with the programs stored in the ROM 12 or storage 14. In this embodiment, the ROM 12 or storage 14 stores a tile diagnostic program for diagnosing abnormalities in tiles on the exterior wall to be diagnosed. The tile diagnostic program may be a single program, or may be a group of programs consisting of multiple programs or modules.

[0044] The ROM 12 stores various programs and various data. The RAM 13 temporarily stores programs or data as a working area. The storage 14 is configured with an HDD (Hard Disk Drive) or SSD (Solid State Drive) and stores various programs including the operating system and various data.

[0045] The input unit 15 includes a pointing device such as a mouse and a keyboard, and is used for various inputs, including a combination of a thermal image of the tile to be diagnosed taken through a polarized lens and a visible light image of the exterior wall tile to be diagnosed. The combination of the thermal image and visible light image of the exterior wall tile to be diagnosed is captured using a thermal imaging camera 20A and a visible light imaging camera 20B connected to the tile diagnosis device 10, as shown in FIG. 19 . The thermal imaging camera 20A captures the thermal image through a polarized lens. The thermal imaging camera 20A may capture the thermal image while rotating the polarized lens. This allows the capture of a thermal image that eliminates heat reflections in all directions. The thermal imaging camera 20A is, for example, an infrared camera.

[0046] The display unit 16 is, for example, a liquid crystal display, and displays various information including the diagnosis results. The display unit 16 may be a touch panel type and function as the input unit 15.

[0047] The communication interface 17 is an interface for communicating with other devices, and uses standards such as Ethernet (registered trademark), FDDI, and Wi-Fi (registered trademark).

[0048] Next, a description will be given of the functional configuration of the tile diagnosis device 10. Fig. 18 is a block diagram showing an example of the functional configuration of the tile diagnosis device 10.

[0049] As shown in FIG. 18, the tile diagnosis device 10 functionally includes an acquisition unit 101, a correction unit 102, a removal unit 103, a diagnosis unit 104, and an output unit 105.

[0050] The acquisition unit 101 acquires a thermal image of the tile to be diagnosed, taken through a polarized lens, and also acquires a visible light image of the tile to be diagnosed.

[0051] Based on the thermal image, the correction unit 102 corrects the pixel value of each pixel in the thermal image in accordance with the brightness of the corresponding pixel in the visible light image.

[0052] Specifically, the slope of a predetermined approximate line representing the relationship between the brightness of the visible light image and the temperature of the thermal image is used as a correction coefficient to correct the pixel value of each pixel in the thermal image from which the joints have been removed according to the brightness of the corresponding pixel in the visible light image. As a result, the higher the brightness, the higher the correction is made, and the lower the brightness, the lower the correction is made.

[0053] The removal unit 103 removes the tile joints from the corrected thermal image based on the pixel values of the thermal image.

[0054] Specifically, based on a comparison with the pixel values of the surrounding pixels of the thermal image, areas where the temperature difference is equal to or greater than a threshold are removed as tile joints.

[0055] The diagnosis unit 104 diagnoses abnormalities in the tile to be diagnosed based on the thermal image after removal.

[0056] Specifically, for a thermal image that has been corrected by the correction unit 102 and from which joints have been removed, a portion where the temperature difference is greater than or equal to a threshold is diagnosed as an abnormal portion of the tile based on a comparison with surrounding pixel values.

[0057] The output unit 105 outputs the diagnostic results as data. For example, the diagnostic results may be output as a file. The output method may include saving the results in a file, transmitting the results to another system, or displaying the results directly on a screen.

[0058] <Action of the tile diagnosis device according to this embodiment> Next, the operation of the tile diagnostic device 10 will be described.

[0059] 20 is a flowchart showing the flow of tile diagnosis processing by the tile diagnosis device 10. The CPU 11 reads out a tile diagnosis program from the ROM 12 or storage 14, expands it into the RAM 13, and executes it to perform the tile diagnosis processing. Data input to the tile diagnosis device 10 is assumed to be acquired by an equipment configuration including a thermal imaging camera 20A and a visible light imaging camera 20B, and the thermal imaging camera 20A and the visible light imaging camera 20B are installed so that the tiles on the exterior wall to be diagnosed are within the imaging ranges of the thermal imaging camera 20A and the visible light imaging camera 20B, respectively. The tile diagnosis processing is an example of a tile diagnosis method.

[0060] First, in step S100, the CPU 11 functions as the acquisition unit 101 to acquire a thermal image of the tile to be diagnosed taken through a polarized lens, and also acquire a visible light image of the tile to be diagnosed.

[0061] In step S102, the CPU 11 functions as the correction unit 102 to correct the pixel value of each pixel in the thermal image according to the brightness of the corresponding pixel in the visible light image, based on the thermal image. Specifically, the CPU 11 corrects the pixel value of each pixel in the thermal image according to the brightness of the corresponding pixel in the visible light image, using the slope of a predetermined approximate line representing the relationship between the brightness of the visible light image and the temperature of the thermal image as a correction coefficient.

[0062] In step S104, the CPU 11, functioning as the removal unit 103, removes tile joints from the corrected thermal image based on the pixel values of the thermal image. Specifically, based on a comparison with the pixel values of the surrounding pixels of the thermal image, the CPU 11 removes, as tile joints, portions where the temperature difference is equal to or greater than a threshold.

[0063] In step S106, the CPU 11, as the diagnosing unit 104, diagnoses an abnormality in the tile to be diagnosed based on the thermal image after the removal. Specifically, for the thermal image corrected by the correcting unit 102 and from which the joints have been removed, the CPU 11 diagnoses a portion where the temperature difference is equal to or greater than a threshold as an abnormal portion of the tile based on a comparison with the surrounding pixel values.

[0064] In step S108, the CPU 11 outputs the diagnostic result as data in the form of the output unit 105. Specifically, the diagnostic result is output to a file or another system, or is displayed on the display unit 16.

[0065] As described above, the tile diagnosis device according to this embodiment acquires a thermal image of a tile to be diagnosed taken through a polarized lens, acquires a visible light image of the tile to be diagnosed, corrects the pixel value of each pixel in the thermal image according to the brightness of the corresponding pixel in the visible light image, and diagnoses abnormalities in the tile to be diagnosed based on the corrected thermal image. This allows for accurate diagnosis of tile abnormalities from the thermal image.

[0066] Furthermore, by removing the tile joints from the thermal image based on the pixel values of the thermal image, it is possible to diagnose abnormalities in the tiles with greater accuracy.

[0067] <Modification> The present invention is not limited to the above-described embodiment, and various modifications and applications are possible without departing from the spirit and scope of the present invention.

[0068] For example, although the case where the thermal imaging camera 20A and the visible light imaging camera 20B are connected to the tile diagnosis device 10 has been described as an example, the present invention is not limited to this. The thermal images and visible light images taken by the thermal imaging camera 20A and the visible light imaging camera 20B at a location other than where the tile diagnosis device 10 is installed may be input to the tile diagnosis device 10.

[0069] In addition, various processes executed by the CPU after reading software (programs) in the above embodiments may be executed by various processors other than the CPU. Examples of such processors include programmable logic devices (PLDs) (such as field-programmable gate arrays (FPGAs)) whose circuit configuration can be changed after fabrication, and application-specific integrated circuits (ASICs) that are dedicated electrical circuits that are processors with circuit configurations specifically designed to execute specific processes. Furthermore, the tile diagnostic process may be executed by one of these various processors, or by a combination of two or more processors of the same or different types (e.g., multiple FPGAs, or a combination of a CPU and an FPGA). Furthermore, the hardware structure of these various processors is, more specifically, an electrical circuit that combines circuit elements such as semiconductor devices.

[0070] In addition, in each of the above embodiments, the tile diagnostic program is described as being pre-stored (installed) in the storage 14, but this is not limiting. The program may be provided in a form stored in a non-transitory storage medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD-ROM (Digital Versatile Disk Read Only Memory), or a USB (Universal Serial Bus) memory. The program may also be downloaded from an external device via a network. [Explanation of symbols]

[0071] 10 Tile diagnostic device 11 CPU 14. Storage 15 Input section 16 Display section 20A Thermal Imaging Camera 20B Visible Light Imaging Camera 101 Acquisition Department 102 Correction unit 103 Removal part 104 Diagnostic Department 105 Output section

Claims

1. an acquisition unit that acquires a thermal image of a tile to be diagnosed by photographing it through a polarized lens and also acquires a visible light image of the tile to be diagnosed; a correction unit that corrects the pixel value of each pixel of the thermal image in accordance with the brightness of the corresponding pixel of the visible light image; a diagnosis unit that diagnoses an abnormality in the tile to be diagnosed based on the corrected thermal image; A tile diagnostic device including:

2. a removal unit that removes the tile joints from the thermal image based on pixel values of the thermal image; The tile diagnosis device according to claim 1 , wherein the diagnosis unit diagnoses abnormalities in the tile to be diagnosed based on the thermal image after the removal.

3. 2. The tile diagnostic device according to claim 1, wherein the thermal image is captured while the polarizing lens is rotated.

4. an acquisition unit acquires a thermal image of a tile to be diagnosed taken through a polarized lens, and also acquires a visible light image of the tile to be diagnosed; a correction unit correcting a pixel value of each pixel of the thermal image in accordance with the brightness of a corresponding pixel of the visible light image; A diagnosis unit diagnoses an abnormality in the tile to be diagnosed based on the corrected thermal image. How to diagnose tiles.

5. A thermal image of the tile to be diagnosed is acquired by photographing it through a polarized lens, and a visible light image of the tile to be diagnosed is also acquired; correcting the pixel value of each pixel of the thermal image according to the brightness of the corresponding pixel of the visible light image; Diagnosing abnormalities in the tile to be diagnosed based on the corrected thermal image. A tile diagnostic program that allows a computer to do this.

Images