A method for displaying at least one specific region in a thermal image of a thermal imaging camera

Abstract

The invention relates to a method (100) for displaying at least one specific region in a thermal image of a thermal imaging camera (1), comprising: providing (101) the thermal image, wherein the thermal image is generated by a detection of a thermal imaging sensor (3) of the thermal imaging camera (1), receiving (102) at least one selection criterion for the specific region in the thermal image based on a user input, creating (103) the specific region based on the received selection criterion, determining (104) a color scale for the created specific region based on minimum and maximum temperature values presented in the created specific region in the thermal image, initiating (105) a display of a blended image, the blended image comprising the created specific region as a thermal image and a remaining region using the determined color scale. Furthermore, the invention also relates to a thermal imaging camera, a computer program, a device and a storage medium for this purpose.

Description

Technical Field

[0001] This invention relates to a method for displaying at least one specific area in a thermal image from a thermal imaging camera. Furthermore, the invention also relates to a thermal imaging camera, computer program, apparatus, and storage medium for this purpose. Background Technology

[0002] Thermal images are typically presented as a single, detected image segment on the display of a thermal imaging camera. Typically, the associated color scale contains all temperatures within the detected image segment, from minimum to maximum. The range from the minimum to the maximum temperature in the image is called the "span," and the color scale is linearly divided from the coldest to the warmest temperature. In current thermal imaging cameras, other modes exist for displaying images. In picture-in-picture mode, only a portion of the image is displayed as a thermal image on the thermal imaging camera's display, with the rest being the image from a visible light camera, which is present in many thermal imaging cameras today. The image segment displayed as a thermal image is predetermined and cannot be set by the user. The span still contains all temperatures present in the entire image. In transparent mode, the image from the visible light camera is placed "behind" the entire thermal image. This is called alpha blending. In "Hotseeker" mode, only the thermal image from the temperature the user needs to determine is displayed, with everything else displayed as a visible light image. In "Coldseeker" mode, the user sets a temperature up to which the image is displayed as a thermal image; above that temperature, a visible light image is displayed. In manual mode, the temperature range can also be adjusted, meaning the user can set upper and lower thresholds, beyond which the image is displayed in monochrome. Then, the colors present in the color scale are divided into temperature ranges within that range. Summary of the Invention

[0003] The subject of this invention is a method for displaying at least one specific area in a thermal image from a thermal imaging camera, a thermal imaging camera, a computer program, and a computer-readable storage medium. Further features and details of the invention are derived from the corresponding preferred embodiments, description, and drawings. Hereinafter, the features and details described in conjunction with the method according to the invention also apply in conjunction with the thermal imaging camera according to the invention, the computer program according to the invention, and the computer-readable storage medium according to the invention, and vice versa, so that the disclosure of this invention can always be cross-referenced.

[0004] The subject of this invention is, in particular, a method for displaying at least one specific region in a thermal image from a thermal imaging camera, the method comprising: - Provides thermal images, which are generated by the detection of the thermal imaging sensor (e.g., an infrared detector array) of a thermal imaging camera. These thermal images can also be synonymously referred to or understood as thermal maps or infrared images, and this is particularly similar for both thermal imaging sensors and thermal imaging cameras. - Based on user input, receive at least one selection condition for a specific region in the thermal image. - Create a specific region based on the received selection criteria. - Based on the minimum and maximum temperature values ​​presented in the specific region created in the thermal image, a color scale is determined for the specific region created. It is also conceivable that, in order to determine the color scale, a defined temperature value is added to and / or subtracted from the minimum and / or maximum temperature value (in short, for example, Min-x and Max+x or Min+x and Max-x are also possible, where x is a defined temperature value, i.e., 5°C). - For example, on the display of a thermal imager, the display of a blended image is initiated, wherein the blended image includes a specific area created using a determined color scale as a thermal image and the remaining area, which is also conceivable.

[0005] In other words, the color scale used for the specific area created determines the color to be displayed. Using the method according to the invention, a user-defined thermal image can be generated, focusing on a selected area, i.e., a specific region, and the color scale of this thermal image is adapted to the temperature within that area. This approach, in particular, enables more detailed analysis of the thermal image within a specific region and can improve the contrast within that region.

[0006] Furthermore, it is conceivable that the creation includes: determining color information and / or temperature information in the thermal image based on at least one received selection condition.

[0007] As a result, color swatches can be precisely adapted to specific areas. Evaluation of color and temperature information allows for fine-tuning of the palette to match the temperature present in that area. This, in particular, leads to improved representation of temperature differences within specific regions.

[0008] Furthermore, within the scope of this invention, it is conceivable that the remaining region corresponds to the grayscale representation of a corresponding segment of the thermal image. This allows for a clear distinction between the focused, specific thermal image region and the remaining region when the mixed image is displayed. The limited color spectrum of the grayscale representation in the remaining region can advantageously provide additional highlighting of specific thermal image regions and thus support visual analysis.

[0009] Optionally, the method may also include: Provides a visible light image, wherein the visible light image is generated by the detection of the camera sensor (especially the visible light camera sensor) of the thermal imaging camera, wherein the thermal image and the visible light image present the same detected scene. The remaining region corresponds to a specific segment of the visible light image, and / or, after alpha blending, a particular region is a superposition of the thermal and visible light images. This allows the display of the blended image to provide users with an improved understanding of the detected scene. The combination of thermal and visually recorded images offers a particularly comprehensive presentation, displaying both temperature information and visual detail. This can be especially helpful for applications where observing both aspects of a scene is crucial.

[0010] Furthermore, it is advantageous that, within the scope of this invention, user input is input on the display (especially a touch-sensitive display) and / or the operating element of the thermal imaging camera. In other words, this allows the user to define specific areas in the thermal image via various input requests (e.g., on the display, especially a touch-sensitive display) or via the operating element on the thermal imaging camera. This increases the flexibility and user-friendliness of the thermal imaging camera.

[0011] Furthermore, it is advantageous that the selection criteria are rectangular or free-form, where a specific region corresponds to the content of the rectangle or the free-form shape. This allows the user to precisely define the desired area in the thermal image. The flexibility in region selection particularly enables more detailed analysis of specific zones and improves contrast within those zones. This results in more efficient visualization and interpretation of the thermal image. Other shapes, such as circles, are also conceivable.

[0012] Alternatively, the selection criterion may be at least one selected object, which is presented in a thermal image or a visible light image, wherein the creation includes the following steps: Based on image recognition, especially segmentation, the boundary of at least one selected object is detected in a thermal image or a visible light image, wherein a specific region corresponds to the content of the detected boundary.

[0013] In other words, here a user can select at least one object shown in a thermal or visible light image and create a specific region based on that object representation. Boundary detection can be performed using segmentation algorithms or, for example, machine learning models. In this way, it is possible for the user to focus the thermal image representation on one or more specific objects, and color scales are automatically adapted to the temperature of that object or within those objects. This, for example, enables detailed analysis of specific elements in the thermal image. Image recognition technology can represent an intuitive and user-friendly method for selecting regions, as the user can simply select at least one desired object.

[0014] In another possibility, user input can be set to manual or automatic focus based on thermal and / or visible light images, where the selection criterion is the resulting focus area, and the creation includes the following steps: The obtained focused area is analyzed to identify the clear area, where a specific area corresponds to the identified clear area.

[0015] This, in particular, enables precise selection of the thermal image region and ensures it is in focus for the user. Automatic or manual focusing allows the user to, for example, selectively highlight areas requiring detailed analysis.

[0016] Sharp regions in an image are particularly well-defined areas where image details are clearly defined. This means, for example, that edges, textures, and fine structures are clearly visible and not blurred. Sharpness can be measured, for example, by analyzing gradients in an image. Gradients, in particular, describe how rapidly intensity values ​​(brightness) change. High gradients can indicate sharp edges. For example, algorithms such as the Sobel or Canny detectors can be used to find edges. The Laplacian operator is a second-derivative operator that identifies edges and regions with high intensity changes. Images with many strongly prominent Laplacian values ​​can indicate sharp regions.

[0017] Sharp regions typically contain a significant amount of high spatial frequencies. Fourier transforms can be used to analyze the frequency components of an image. Images with many high spatial frequency components tend to be particularly sharp. Visual inspection can determine whether a region possesses fine detail and sharp edges. Sharp regions also tend to have higher contrast differences between adjacent pixels.

[0018] To analyze the obtained focused region, algorithms that analyze texture and edge information can be used. Furthermore, trained machine learning models can be used to automatically classify sharp and blurry regions.

[0019] Within the scope of this invention, it is advantageous if the method further includes: Specifically, based on temperature information from thermal images, at least one additional specific region within the thermal image is identified, wherein the at least one additional specific region lies within the minimum and maximum temperature values. Within the scope of initiating the display of the blended image, the blended image also includes at least one additional specific region obtained using the determined color scale as a thermal image and a correspondingly adapted remaining region. In other words, this allows additional specific regions in the blended image to be displayed as thermal images, these additional specific regions also falling within the range between the minimum and maximum temperature values ​​of the created specific region. The remaining region preferably corresponds to a reduction in the size of the additional specific region.

[0020] The subject of this invention is also a thermal imaging camera, which includes: A data processing apparatus configured to perform the method according to the invention, wherein the data processing apparatus is, for example, an integrated circuit or a microprocessor or a similar device. Thermal imaging sensors, such as infrared detector arrays, are configured to detect thermal images. Camera sensors, especially visible light camera sensors, are configured to detect visible light images. A display, particularly a touch-sensitive display, and at least one operating element, wherein the display and / or the at least one operating element are configured to detect user input, and wherein the display is further configured to display the mixed image.

[0021] Therefore, the thermal imaging camera according to the invention brings the same advantages as described in detail in conjunction with the method according to the invention.

[0022] The subject of this invention is also a computer program, and more particularly a computer program product, comprising instructions that, when executed by at least one computer, cause the at least one computer to perform the method according to the invention. Therefore, the computer program according to the invention provides the same advantages as described in detail in conjunction with the method according to the invention.

[0023] The subject of this invention is also an apparatus for data processing, configured to perform the method according to the invention. As such an apparatus, at least one computer may be provided, which executes a computer program according to the invention. The computer may have at least one processor for executing the computer program. A non-volatile data memory may also be provided, in which the computer program is stored, and which the computer program may be read from the non-volatile data memory by the processor for execution.

[0024] The subject matter of this invention can also be a computer-readable storage medium having a computer program according to the invention and / or including instructions that, when executed by at least one computer, cause the at least one computer to perform the method according to the invention. The storage medium is, for example, constructed as a data storage device, such as a hard disk and / or non-volatile memory and / or a memory card. The storage medium may, for example, be integrated into a computer.

[0025] Furthermore, the method according to the invention can also be implemented as a computer-based method. Alternatively or additionally, at least one disclosed method step may be computer-implemented and / or automatically executed. Attached Figure Description

[0026] Further advantages, features, and details of the invention will become apparent from the following description, in which embodiments of the invention are described in detail with reference to the accompanying drawings. Here, the features mentioned in the claims and specification may be essential to the invention individually or in any combination. The drawings show: Figure 1 A schematic visualization of a thermal imaging camera according to an embodiment of the present invention is shown. Figure 2 A schematic diagram of a thermal imaging camera according to an embodiment of the present invention is shown. Figure 3 A schematic visualization illustrating a method, apparatus, storage medium, and computer program according to embodiments of the present invention is provided. Figure 4 A method according to an embodiment of the present invention is shown. Detailed Implementation

[0027] The following reference Figure 1 and Figure 2 A thermal imaging camera 1 according to an embodiment of the present invention is described, particularly in the form of a handheld thermal imaging camera 1. Figure 1 and Figure 2 An exemplary embodiment of the thermal imaging camera 1 is shown in both a front perspective view and a rear perspective view. The thermal imaging camera 1 includes a housing 12 with a handle 14. The handle 14 allows the thermal imaging camera 1 to be comfortably held in one hand during use. The housing 12 of the thermal imaging camera 1 also has an output device in the form of a display 18 (especially a touch-sensitive display 18) and an operating element 5 for user input and control of the thermal imaging camera 1 on the user-facing side 16 during use. In particular, the thermal imaging camera 1 has a trigger 5a, which the user can use to trigger a non-contact determination of the temperature of the surface of the object to be inspected, especially the temperature distribution of the object surface.

[0028] On the side 26 of the housing 12 facing away from the user, an entrance port 28 is provided within the housing 12. Thermal radiation radiated by the object 24, especially by the surface 22 of the object 24 within the measurement range, can enter the thermal imaging camera 1 through this entrance port. Immediately behind the entrance port 28, a lens system 34, serving as an optical device, is provided in a lens barrel to reduce scattered light. The lens system 34 is transparent to radiation in the infrared range and is used, for example, to focus the thermal radiation onto the thermal imaging sensor 3 (especially an infrared detector array) of the thermal imaging camera 1.

[0029] On the side 26 facing away from the user during use, in one embodiment of the thermal imaging camera 1, a camera sensor 4 operating in the visible spectrum is also provided, by means of which a visible light image of the measurement range can be recorded. This visible light image can be output together with a thermal image generated from a user-initiated temperature measurement, particularly, according to embodiments of the invention, at least partially superimposed or overlaid with the thermal image as a mixed image output. The camera sensor 4 can be implemented, for example, as a CCD image sensor.

[0030] On the underside of the thermal imaging camera 1, the handle 14 has a receiver 42 for receiving an energy storage device 44, which may be implemented, for example, in the form of a rechargeable battery or a battery.

[0031] In addition, the thermal imaging camera 1 includes a device 10 for data processing, such as... Figure 2 As shown schematically in the diagram.

[0032] exist Figure 3 The diagram schematically illustrates a method 100, apparatus 10, storage medium 15, and computer program 20 according to an embodiment of the present invention.

[0033] Figure 3 In particular, an embodiment of a method 100 for displaying at least one specific region in a thermal image of a thermal imaging camera 1 is shown. In a first step 101, a thermal image is provided, wherein the thermal image is generated by detection by the thermal imaging sensor 3 of the thermal imaging camera 1. In a second step 102, at least one selection condition for a specific region in the thermal image is received based on user input. In a third step 103, the specific region is created based on the received selection condition. In a fourth step 104, a color scale for the created specific region is determined based on the minimum and maximum temperature values ​​exhibited in the created specific region in the thermal image. In a fifth step 105, the display of a blended image is initiated, wherein the blended image includes the specific region created using the determined color scale as a thermal image and the remaining region.

[0034] Figure 4A method 200 according to an embodiment of the present invention is shown. In step 201, it is specifically confirmed whether user input has been made via the touch-sensitive display 18 of the thermal imaging camera 1. If not, step 202 preferably determines whether user input has been made in the form of focusing. If this is also not the case, the method can be terminated according to step 203. If user input has been made via the touch-sensitive display 18 of the thermal imaging camera 1, the specific region is preferably created as a rectangle or free shape according to step 202b. If user input has been made in the form of focusing, the user focuses, in particular, on the desired image region or the object presented in the thermal image according to step 204. Subsequently, according to step 205, the specific region can be created as a focused, sharp region according to the present invention. According to step 206, the minimum and maximum temperature values ​​in the specific region can then be automatically determined. Subsequently, according to step 207, the color scale can be limited to a range between the minimum and maximum temperature values. Finally, according to step 208, a blended image can be displayed, wherein the blended image includes the specific region when using the color scale as a thermal image and the remaining region as a grayscale thermal image or as a visible light image.

[0035] According to embodiments of the invention, the area displayed as a thermal image can be sized by the user. That is, unlike picture-in-picture mode, the area displayed as a thermal image is particularly adaptive. Therefore, the user can "tailor" the area to be displayed. Furthermore, the picture-in-picture mode according to the prior art suffers from the problem that the span, i.e., the range from minimum to maximum temperature values, still covers all temperatures present in the entire image; that is, the color stops in the picture-in-picture segment are particularly based on the span of the entire image. According to embodiments of the invention, the span can be adapted to a specific area selected by the user; that is, the color stops specifically include only the temperatures within the selected specific area. Thus, the selected specific area can be advantageously displayed with higher contrast.

[0036] Using a touch-sensitive display 18 or an operating element 5, a user can, for example, draw a rectangle in which the thermal image should be displayed. Preferably, color stops are then automatically adapted to the area, i.e., the coldest and warmest points are determined and introduced as boundaries of the color stops. The remainder of the blended image can then be displayed, for example, as a visible light image or a grayscale thermal image. Alternatively, the area can be restricted to a single object by object recognition in the visible light or thermal image. Another possibility for determining the area to be displayed as a thermal image is, in particular, to focus a specific area (e.g., in the foreground) into sharp focus using a focusing optics. Only the “sharp” area is then preferably displayed as a thermal image, and the color stops can be adapted as described above.

[0037] According to one possibility, the determination of a specific area can therefore be made by means of the touch-sensitive display 18 or the operating element 5. The user can use the touch-sensitive display 18 or the operating element 5 to determine a rectangular or free-form area in which they wish to display a thermal image. It is also possible to determine the area by selecting an object in a visible light image or a thermal image. For example, the user clicks on an object representation on the touch-sensitive display 18, and the boundaries of the object representation can be detected by means of image recognition. The specific area is preferably limited to the object representation. Subsequently, it is preferably automatically determined which temperatures exist in the image segment and color scales are limited accordingly.

[0038] According to another possibility, the determination of a specific area can be achieved by focusing. This presupposes, in particular, the existence of a focusing optical device, meaning the focus must preferably be manually or automatically adjustable. Here, the user can focus the image on an object or image area of ​​their choice. Then, specifically automatically, it detects where the image is sharp, and the rendering of the thermal image is limited to that sharp area. Subsequently, preferably automatically, it determines which temperatures exist in the image segment and accordingly limits the color stops.

[0039] Alternatively, a temperature range can be determined. In this alternative, the user can select a segment from the thermal image. Preferably, the maximum and minimum temperatures are extracted from this segment. In the blended image, the segments falling within this temperature range are then preferably displayed as thermal images. The remainder of the image is preferably displayed as a grayscale representation or a visible light image.

[0040] The foregoing description of the embodiments is merely illustrative and describes the invention within the scope of examples only. Of course, the various features of the embodiments can be freely combined with each other without departing from the scope of the invention, as long as it is technically meaningful.

Claims

1. A method (100) for displaying at least one specific region in a thermal image of a thermal imaging camera (1), comprising: Provide (101) the thermal image, wherein the thermal image is generated by the detection of the thermal imaging sensor (3) of the thermal imaging camera (1), Based on user input, receive (102) at least one selection condition for the specific region in the thermal image. Based on the received selection criteria, create the specific region described in (103). Based on the minimum and maximum temperature values ​​presented in a specific region created in the thermal image, a color scale for the specific region is determined (104). Initiate (105) the display of a blended image, wherein the blended image comprises a specific region created using a determined color scale as a thermal image and the remaining region.

2. The method (100) according to claim 1, characterized in that, The creation (103) includes: For at least one selection condition received, determine the color information and / or temperature information in the thermal image.

3. The method (100) according to claim 1 or 2, characterized in that, The remaining region corresponds to the grayscale representation of the corresponding segment of the thermal image.

4. The method (100) according to claim 1 or 2, characterized in that, The method (100) further includes: Provide a visible light image, wherein the visible light image is generated by the detection of the camera sensor (4) of the thermal imaging camera (1), wherein the thermal image and the visible light image present the same detected scene. Wherein, the remaining region corresponds to the corresponding segment of the visible light image, and / or, wherein the specific region is a superposition of the thermal image and the visible light image after performing alpha blending.

5. The method (100) according to any one of the preceding claims, characterized in that, The user input is input on the display (18) and / or input on the operating element (5) of the thermal imaging camera (1).

6. The method (100) according to claim 5, characterized in that, The selection criteria are a rectangle or a free shape, wherein the specific region corresponds to the content of the rectangle or the free shape.

7. The method (100) according to claim 5, characterized in that, The selection criteria are at least one selected object, which is presented in the thermal image or the visible light image, wherein the creation (103) includes the following steps: Based on image recognition, especially segmentation, the boundary of at least one selected object in the thermal image or the visible light image is detected, wherein the specific region corresponds to the content of the detected boundary.

8. The method (100) according to any one of the preceding claims, characterized in that, The user input is manual or automatic focusing based on the thermal image and / or the visible light image, wherein the selection criteria are the obtained focus area, and wherein the creation (103) includes the following steps: The obtained focused area is analyzed to identify the clear area, wherein the specific area corresponds to the identified clear area.

9. The method (100) according to any one of the preceding claims, characterized in that, The method (100) further includes: Specifically, based on the temperature information of the thermal image, at least one additional specific region in the thermal image is identified, wherein the at least one additional specific region lies within the minimum and maximum temperature values. Within the scope of initiating (105) the display of the blended image, the blended image also includes at least one additional specific region obtained using the determined color scale as a thermal image and a correspondingly adapted remaining region.

10. A thermal imaging camera (1), comprising: The apparatus (10) for data processing is configured to perform the method (100) according to any one of claims 1 to 9. A thermal imaging sensor (3), wherein the thermal imaging sensor (3) is configured to detect thermal images, A camera sensor (4), wherein the camera sensor (4) is configured to detect visible light images, The display (18) and at least one operating element (5) are configured to detect user input, wherein the display (18) and / or the at least one operating element (5) are configured to display a mixed image.

11. A computer program (20) comprising instructions that, when executed by at least one computer (10), cause the at least one computer to perform the method (100) according to any one of claims 1 to 9.

12. A computer-readable storage medium (15) comprising instructions that, when executed by at least one computer (10), cause the at least one computer to perform the steps of the method (100) according to any one of claims 1 to 9.

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