JP2000227362A - Temperature change-detecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a detecting apparatus which can correctly detect an abnormality of a temperature change of outer walls of facilities such as a power- generating plant and the like. SOLUTION: An infrared image by a temperature of a facility outside wall is taken by an infrared camera 1 into an image-processing apparatus (step A2). A characteristic point of the taken image is calculated (step A4). A characteristic point of a reference image taken beforehand is calculated (step A6). After characteristic points of both images are registered (step A7), a subtraction between the taken image and reference image is carried out (step A8). A temperature abnormality of the facility outside wall is compared on the basis of the reduction value (step A9). Accordingly, shaking of the infrared camera can be corrected and a correct temperature can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an abnormal temperature change,
For example, the present invention relates to a temperature change detection device that detects an abnormality in a temperature change of an outer wall of a facility such as a power plant or a chemical plant.

[0002]

2. Description of the Related Art In power plants and chemical plants that use fuel, raw materials, catalysts, etc. by heating and pressurizing, cracks in pipes, heat-resistant containers, and falling off heat-insulating materials are a precursor to troubles such as fires and explosions. In addition, the outer wall temperature may change abnormally due to excessive reaction of the raw materials. Conventionally, detection of this abnormal temperature change is performed by a thermocouple detector, a resistance temperature detector, an infrared sensor detector, an infrared image detector, or the like.

[0003] A thermocouple detector detects an abnormality in a temperature change using thermoelectromotive force generated by a thermocouple. Further, the temperature-measuring resistance detector detects an abnormality in temperature change by using a change in electric resistance due to temperature. In addition, infrared sensor-based detectors use infrared energy generated by the heat-generating part to detect abnormal temperature changes.Infrared image-based detectors detect changes in infrared images captured from an infrared camera. The temperature change is detected by the processing device to detect an abnormality in the temperature change.

[0004]

However, the above-mentioned conventional detector for detecting an abnormality in temperature change has the following problems. (1) In a thermocouple type detector, a resistance temperature type detector, and an infrared sensor type detector, it takes a lot of labor and cost to install each heat sensing part (a plurality of installations) and wiring, and the power generation plant It is difficult to use in large facilities such as chemical plants. It is also difficult to use outdoors. (2) Although the infrared image detector can overcome the problem (1), monitoring outside the imaging range is impossible. That is, if the distance between the infrared camera and the monitoring target is increased, the monitoring range is widened, but high-precision temperature measurement cannot be performed due to attenuation of infrared energy by air. On the other hand, if the distance between the infrared camera and the monitoring target is reduced, highly accurate temperature measurement can be performed, but many expensive infrared cameras are required. In addition, when the head is swung by the electric pan head, it is not possible to grasp a minute temperature change due to mechanical shake of the movable part.

The present invention is intended to solve these problems. An infrared camera is mounted on an electric pan head capable of changing a shooting range, and an infrared image of a monitoring range is shot by the infrared camera. The image signal of the camera is taken into the image processing device, and the image processing operation is performed to automatically detect the abnormality of the temperature change over a wide range, and to correct the image due to the mechanical shake of the electric pan head. It is intended to provide a change detection device. Another object of the present invention is to provide a temperature change detection device that eliminates erroneous detection due to disturbances such as sunlight and improves detection accuracy.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to an infrared camera, in which a temperature change detection device can capture an infrared image based on the temperature of a monitored object and output the image as an image signal, and an infrared camera. An electric camera platform that supports the infrared camera so that the photographing range of the camera can be changed, an image processing device that captures an image signal from the infrared camera and performs image processing calculation, and operation of the electric camera platform and the image processing device And a control device for controlling the image processing device, the image processing device, in the captured image obtained by performing image processing of the image signal captured from the infrared camera, the infrared source at a preset position in the captured image Means for calculating as a feature point, a reference image which is previously captured by the same image processing apparatus and has a feature point at the same position as the feature point of the captured image, and a feature point of the captured image having the same position So as to have a means for alignment of the two images, and means configured to issue solved by means of performing subtraction between images of the same two images.

Further, the present invention provides an infrared camera in which the temperature change detecting device can capture an infrared image based on the temperature of the monitoring target and output the image as an image signal, and a visible camera capable of capturing the monitoring target and outputting it as a visible image signal. And, the electric camera platform supporting the infrared camera and the visible camera so that the shooting range of the infrared camera and the visible camera can be changed, and capturing the image signal and the visible image signal from the infrared camera and the visible camera, respectively. An image processing device for performing image processing calculations; and a control device for controlling the operation of the electric pan head and the image processing device. The image processing device performs image processing on the image signal captured from the infrared camera. Means for calculating, as a feature point, an infrared source located at a preset position in a captured image obtained by Means for aligning the two images so that the reference image and the feature point of the captured image are featured at the same position as the feature point of the captured image and the feature point of the captured image at the same position. Means for performing image-to-image subtraction of the two images, means for performing a comparison operation for comparing the operation value thereof with a preset reference value for determining abnormality in temperature change,
If it is determined that the temperature is abnormal,
An operation for removing the abnormal temperature change as a disturbance when a position showing the abnormal temperature change in the visible captured image obtained by performing image processing on the visible image signal captured from the visible camera has high luminance. And a means for solving the problem.

In the temperature change detecting device of the present invention, a wide range of infrared images obtained by one infrared camera is image-processed, and its characteristic points are calculated.
By comparing with a reference infrared image (subtraction between images), equipment costs are reduced, mechanical shake of the electric pan head can be corrected, and abnormal detection of temperature changes over a wide range is automatically detected. And can be performed accurately.

Further, by additionally installing a visible camera and processing an image signal from the visible camera, erroneous detection due to sunlight or the like in a plant outdoors or in a place near the outdoors can be eliminated.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a temperature change detecting device according to a first embodiment of the present invention; FIG. FIG. 2 is a flow chart showing the operation of the image processing apparatus, FIG. 3 (a) is a view showing a captured image,
FIG. 3B is a view showing a state after the characteristic points of the captured image have been calculated, and FIG.
3D shows a reference image, FIG. 3D shows a state after the feature points of the reference image have been calculated, FIG. 3E shows a state when the captured image is aligned with the reference image, and FIG. 7 is a diagram showing a state after a comparison operation of both images. FIG.

FIGS. 4 to 6 show a temperature change detecting device according to a second embodiment of the present invention. FIG. 4 is a schematic configuration diagram showing the entire device, FIG. 5 is a flowchart showing the operation of the image processing device, 6A is a diagram showing a captured image, FIG. 6B is a diagram showing a captured image after calculating feature points, FIG. 6C is a diagram showing a reference image, and FIG. FIG. 6 (e) shows the image after the feature point calculation, FIG. 6 (e) shows the position of the captured image and the reference image at the time of alignment, FIG. 6 (f) shows the image after the comparison operation of both images, FIG.
(g) is a diagram showing a visible captured image.

First, a first embodiment of the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 denotes an infrared camera, and the infrared camera 1 captures and outputs an infrared image based on a temperature (for example, watt value or Joule heat) of a monitoring range of a monitoring target 10. The infrared camera 1 is mounted on the electric pan head 2 and rotates a predetermined shooting range, that is, a monitoring range horizontally and vertically, and shoots the state of the range with the infrared camera.

Reference numeral 3 denotes an image processing device for processing an image signal from the infrared camera 1. The image processing device 3 captures an image signal from the infrared camera by an image capturing device 31 provided therein. The image processor 32 and the memory 33 perform image processing calculations. Memory 33
Is composed of a memory A33a, a memory B33b and a memory X33x.

Further, the electric pan head 2 and the image processing device 3
And a control device 4 for controlling the image processing and executing the image processing operation according to a preset algorithm. In addition, a display device 5 for displaying an infrared image via the image processing device 3 and an operation terminal 6 for operating the control device 4 and grasping the monitoring state are provided.

The electric pan head 2 is fixed at an arbitrary position, and rotates horizontally or vertically at a fixed angle. The correction of the image due to the movement of the electric camera platform 2 is performed by the control device 4 and the image processing device 3 to perform an image subtraction process.

Next, the image processing operation of the image processing apparatus 3 will be described with reference to the flowchart of FIG. When the system is started (started), the imaging range of the infrared camera 1 is moved by swinging the electric pan head 2 (step A ₁ ), and an image signal of the infrared camera 1 is fetched (step A ₂ ) and stored in the memory A 33 a. (Step A ₃ ).

In an image (captured image) obtained by processing the captured image signal (captured image) (see FIG. 3A), an infrared light source at a preset position is calculated as a feature point (step A).
₄ ) (See FIG. 3 (b)). At this time, a heat source serving as a feature point is set in a shooting range of the infrared camera 1.

Here, a method of correcting an image due to mechanical shake of the electric pan head 2 will be described. After storing the captured images of the current in the memory A33a, it calculates the feature points of the image (Step A _4), then placed in ipecac advance in normal time (infrared camera) image (a reference image: This reference image also has a feature point is set to the same position as sample image) in reference (FIG. 3 (c)) stored in the memory X33x (step a _5), likewise calculates the feature point (step a ₆₎ ( FIG.
(d)).

The captured image is moved so that the respective characteristic points of the reference image (memory X) and the captured image (memory A) are at the same position (step A ₇ ) (see FIG. 3 (e)). Perform an image-to-image reduction between the image and the captured image, and store the result in memory B.
The data is stored in the storage 33b (step A ₈ ), and is used as data for correcting mechanical shake of the electric pan head 2. Thereafter, the set value of the temperature change to be determined as an abnormal condition and the contents of the memory B33b are compared (step A ₉ ), and if a value larger than the set value exists in the memory B33b (see FIG. 3 (f)). ), A temperature change abnormality alarm is issued by the operation terminal 6 (step A ₁₀ ).

As described above, according to the temperature change detecting device of the first embodiment, a wide-range infrared image obtained by one infrared camera is image-processed and its characteristic points are calculated. Since the comparison with the reference infrared image (subtraction between images) is performed, the equipment cost is reduced, and the mechanical shake of the electric pan head can be corrected.
Abnormality detection of a wide-range temperature change can be performed automatically and accurately.

Next, a second embodiment of the present invention will be described with reference to FIGS. The temperature change detection device according to the second embodiment includes an infrared camera 1, an electric camera platform 2, an image processing device, a control device, and the like, which are the same as the temperature change detection device according to the first embodiment. 11 is added to the electric pan head 2.

The visible camera 11 automatically performs the image processing calculation of the temperature change based on the wide-range infrared image obtained by the infrared camera 1 in the same manner as in the first embodiment, and then detects the temperature abnormality. By re-image processing with the image signal from the visible camera 11, it is determined whether or not it is a true abnormal temperature change location excluding a disturbance location due to the sun,
Installed to detect. That is, the infrared camera 1 and the visible camera 11 capable of visually observing the monitoring target capture and output an infrared image and a visible image of a shooting range, that is, a monitoring range.

The electric camera platform 2 is equipped with an infrared camera 1 and a visible camera 11 so that their photographing ranges can be changed. The image processing device 13 captures each image signal from the infrared camera 1 and the visible camera 11 by an image capturing device 131 provided therein, and performs an image processing operation by an image processing device 132 and a memory 133. Memory 1
33 is a memory A133a, a memory B133b, a memory C133c
And a memory X133x.

The control device 14 controls the electric camera platform 2 and the image processing device 13 and executes an image processing operation according to a preset algorithm. An infrared image or a visible image is displayed on the display device 5 via the image processing device 13. The operation terminal 6 operates the control device 14 and grasps a monitoring state.

Next, the image processing operation of the image processing apparatus 13 will be described with reference to the flowchart of FIG. When the system is started (started), the imaging range of the infrared camera 1 is moved by swinging the electric pan head 2 (step B ₁ ), and the image signal of the infrared camera 1 is fetched (step B ₂ ) and stored in the memory A 133 a. (Step B ₃ ).

In the captured image (captured image) (see FIG. 6A), an infrared source located at a preset position is calculated as a feature point (step B ₄ ) (see FIG. 6B). ). At this time, a heat source serving as a feature point is set in a shooting range of the infrared camera 1.

Next, an infrared camera image previously captured (reference image; the same as the reference image of the first embodiment)
(Step B ₅ ), save it in the memory X133x, and calculate the feature points similarly (Step B ₆ ) (FIG. 6).
(d)).

The captured image is moved so that the respective feature points of the reference image (see FIG. 6C) (memory X) and the captured image (see FIG. 6A) (memory A) are at the same position. and (step B ₇₎ (see FIG. 6 (e)), after alignment, is performed between images decrease Starring the reference image and the sample image, storing the result in memory B133b (step B _8). Thereafter, the set value of the temperature change to be determined as an abnormal condition is compared with the contents of the memory B (step B ₉ ), and if a value larger than the set value exists in the memory B 133 b (FIG. 6 (f)) ), And store as a temperature change abnormality alarm.

Further, an image signal from the visible camera 11 mounted on the electric pan head 2 together with the infrared camera 1 is fetched (step B ₁₀ ) and stored in the memory C 133 c (step B ₁₁ ). In the visible captured image (see FIG. 6 (g)), refer to the position where the temperature change abnormality alarm is issued. If it is very bright (high accuracy), it is determined that the sunlight is direct or reflected. discriminated (step B _12), it is removed as a disturbance, when it is determined that it is not the disturbance emit alarming operation terminal 6 by the warning process (step B _13).

In general, the wattage and Joule heat of sunlight (direct and reflected) are originally very large and are incomparable with combustion light. Therefore, when considered simply, in the above description, a very large numerical value photographed by the infrared camera 1 may be detected as sunlight. However, the situation in which sunlight enters is complicated because it is affected by fine weather, cloudy weather, seasons, and the like, and the reliability of an infrared camera alone is low. Therefore, in the second embodiment, the visible camera 11 is added, and the reprocessing is performed based on the luminance or the luminous intensity to determine whether it is sunlight.

Therefore, the apparatus according to the second embodiment processes the image signal from the visible camera 11 in addition to the operation and effect of the apparatus according to the first embodiment. In addition, erroneous detection due to the sun can be excluded, and monitoring with a higher probability than the device of the first embodiment can be performed. Note that the visible camera 11 can also see the site as a real image.

[0032]

As described above, according to the temperature change detecting device of the present invention, the following effects can be obtained. (1) Image processing is performed on a wide range of infrared images obtained by one infrared camera, and its feature points are calculated to compare with a reference infrared image (subtraction between images). Therefore, it is possible to correct the mechanical shake of the electric pan head while keeping the equipment cost low, and it is possible to automatically and accurately detect a temperature change abnormality in a wide range. (2) Since a visible camera is added and the image signal from the visible camera is also processed, erroneous detection due to disturbance such as sunlight can be eliminated in a field or a plant near the field.
Temperature change detection with higher probability becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an entire temperature change detection device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the image processing apparatus.

FIG. 3A is a view showing the captured image. (b) The figure after the feature point calculation of the captured image. (c) The figure which shows the same reference image. (d) The figure which shows the reference image after the feature point calculation. (e) The figure which shows the time of the position alignment of the captured image and the reference image. (f) The figure which shows the both images after the comparison operation.

FIG. 4 is a schematic configuration diagram showing the entire temperature change detection device according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of the image processing apparatus.

FIG. 6A is a view showing the captured image. (b) The figure after the feature point calculation of the captured image. (c) The figure which shows the same reference image. (d) The figure which shows the reference image after the feature point calculation. (e) The figure which shows the time of the position alignment of the captured image and the reference image. (f) The figure which shows the both images after the comparison operation. (g) The figure which shows the same visible capture image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Infrared camera 2 Electric pan head 3.13 Image processing device 4,14 Control device 5 Display 6 Operation terminal 10 Monitoring target 11 Visible camera 31, 131 Image capture device 32, 132 Image processor 33, 133 memory 33a, 133a memory A 33b, 133b memory B 133c memory C 33x, 133x memory X

Claims (2)

[Claims] An infrared camera capable of shooting an infrared image based on the temperature of a monitoring target and outputting the image as an image signal, an electric pan head supporting the infrared camera so that the shooting range of the infrared camera can be changed, and the infrared camera An image processing device that captures the image signal and performs an image processing operation, and a control device that controls the operation of the electric pan head and the image processing device, wherein the image processing device captures the image signal from the infrared camera. Means for calculating, as a feature point, an infrared light source at a preset position in a captured image obtained by performing image processing on the image signal, and the captured image previously captured by the image processing apparatus; Means for aligning the reference image having a feature point at the same position as the feature point of the captured image and the feature point of the captured image, and performing image subtraction between the two images. means It is characterized by having
Temperature change detection device. 2. An infrared camera capable of capturing an infrared image according to a temperature of a monitoring target and outputting the image as an image signal, a visible camera capable of capturing the monitoring target and outputting the same as a visible image signal, and the infrared camera and the visible camera. An electric camera platform that supports the infrared camera and the visible camera so that the imaging range can be changed, and an image processing device that performs image processing calculations by capturing image signals and visible image signals from the infrared camera and the visible camera, respectively, With a control device for controlling the operation of the above-mentioned electric pan head and the image processing device,
Means for calculating, as a feature point, an infrared source located at a preset position in a captured image obtained by performing image processing on the image signal captured from the infrared camera, The reference image having the feature point at the same position as the feature point of the captured image and the feature point of the captured image are aligned in advance so that the feature point of the captured image is aligned with the feature point of the captured image. Means for performing subtraction between images of the two images, and means for performing a comparison operation for comparing the calculated value with a preset reference value for determining a temperature change abnormality, and performing the comparison operation. When it is determined that the abnormal temperature change, when the position showing the abnormal temperature change in the visible captured image obtained by performing image processing on the visible image signal captured from the visible camera is high luminance,
A temperature change detecting device comprising means for performing an operation for removing the abnormal temperature change as a disturbance.