Network camera using flame sensitivity gauge and fire detection method using same

Abstract

The present invention relates to a network camera using a flame sensitivity gauge and a fire detection method using same. According to the present invention, the network camera for providing a flame sensitivity gauge for a site comprises: an image acquisition unit that acquires a captured image of a surveillance area; a flame detection sensor that, on the basis of infrared rays, detects flames that have occurred on the site; a gauge generation unit that processes the flame sensitivity gauge by using a flame sensing value sensed in real time from the flame detection sensor; and a control unit that transmits, in real time to a network-connected monitoring apparatus, an on-site surveillance image generated by overlaying the flame sensitivity gauge on the captured image. According to the present invention, a flame sensing value observed on the site is intuitively provided in the form of a flame sensitivity gauge within a captured image by a network camera installed around a surveillance area, so as to quickly determine and respond to a fire situation.

Description

Network camera using flame sensitivity gauge and fire detection method using the same

[0001] The present invention relates to a network camera using a flame sensitivity gauge and a fire detection method using the same, and more particularly, to a network camera that can intuitively check the state of flames at a surveillance target site using an image and a flame sensitivity gauge and can quickly respond in the event of a fire, and a fire detection method using the same.

[0002] Typically, fire detection systems utilize fire detectors, such as flame, smoke, or temperature sensors installed on the ceiling of a structure. A conventional fire detection system consists of a fire detector and a receiving panel that receives a fire detection signal from the detector and indicates the presence of a fire.

[0003] However, conventional fire detectors can be triggered by causes other than fire, and there is a very high possibility of false alarms due to malfunction of the fire detector.

[0004] Frequent fire detection signals, often caused by malfunctioning fire detectors, make it difficult for fire detection system managers to physically visit the scene and visually confirm the presence of a fire. This has led to instances where, even when a fire is detected, managers avoid triggering fire alarms until they can visually confirm the signal.

[0005] Recently, systems that can detect fires from both close and remote locations are being used using fire detection sensors such as flame sensors (e.g., infrared or ultraviolet sensors), temperature sensors, and smoke sensors.

[0006] However, these conventional fire detection systems do not have separate sensitivity control for the fire detection sensor, and when an actual fire occurs, they judge the detection result based on the initial setting values ​​such as temperature or smoke, and transmit the information to the control room or generate an alarm sound at the installation site to notify the fire alarm. Therefore, when used in installation locations such as outdoors or laboratories where the environment changes from moment to moment, there are many errors and problems with sensitivity settings.

[0007] The technology underlying the present invention is disclosed in Korean Patent No. 10-2368191 (announced on February 28, 2022).

[0008] The purpose of the present invention is to provide a network camera and a fire detection method using the same, which enable a manager to quickly recognize and respond to a fire by intuitively providing a flame sensing value observed at a site in the form of a gauge in a video captured by a camera monitoring the site.

[0009] The present invention relates to a network camera that provides a flame sensitivity gauge for a scene, comprising: an image acquisition unit that acquires a photographed image of a surveillance area; a flame detection sensor that detects a flame generated at a scene based on infrared rays; a gauge generation unit that processes a flame sensitivity gauge using a flame sensing value sensed in real time from the flame detection sensor; and a control unit that transmits a scene surveillance image generated by overlaying the flame sensitivity gauge on the photographed image to a network-connected monitoring device in real time.

[0010] In addition, the control unit can generate the on-site surveillance image by overlaying the flame sensitivity gauge processed into a set shape at a preset location within the photographed image.

[0011] In addition, the control unit compares the currently sensed flame sensing value with a threshold value, and if the value is greater than the threshold value, recognizes that a fire has occurred at the site and transmits a fire occurrence alarm to the monitoring device, and the monitoring device outputs the site surveillance image received from the network camera through an output means, and when the fire occurrence alarm is received, the fire occurrence alarm can be output together with the site surveillance image.

[0012] In addition, the gauge generating unit processes the flame sensitivity gauge, which is formed of a bar-shaped gauge box and a gauge bar of a set color whose length varies dynamically according to the flame sensing value within the gauge box, and the gauge box is divided into a first section lower than a threshold value for a fire alarm and a second section higher than the threshold value, wherein the first section has a different color from the gauge bar, and the length of the gauge bar can increase in an upward direction within the gauge box.

[0013] In addition, the network camera further includes an image analysis unit that analyzes the captured image when the fire occurs to detect the location of ignition within the captured image, and the control unit can overlay the flame sensitivity gauge around the location of ignition within the captured image to generate the on-site surveillance image.

[0014] In addition, the gauge generating unit processes the flame sensitivity gauge, which is formed of a donut-shaped gauge box and a curved easy bar of a set color whose length dynamically changes according to the flame sensing value in the gauge box, and the gauge box is divided into a first section lower than a threshold value for a fire alarm and a second section higher than the threshold value, wherein the first section has a different color from the gauge bar, and the length of the gauge bar can increase in a clockwise direction within the gauge box.

[0015] In addition, the present invention provides a fire surveillance method performed by a network camera, comprising: a step of acquiring a photographed image of a surveillance area; a step of detecting a flame occurring at a site based on infrared rays using a flame detection sensor installed in the network camera; a step of processing a flame sensitivity gauge using a flame sensing value sensed in real time from the flame detection sensor; and a step of overlaying the flame sensitivity gauge on the photographed image to generate an on-site surveillance image; a step of transmitting the generated on-site surveillance image in real time to a network-connected monitoring device; and a step of comparing the currently sensed flame sensing value with a threshold value and recognizing that a fire has occurred at the site if the value is higher than the threshold value and transmitting a fire occurrence alarm to the monitoring device.

[0016] In addition, the step of generating the on-site surveillance image can generate the on-site surveillance image by overlaying the flame sensitivity gauge processed into a set shape at a preset position within the photographed image.

[0017] In addition, the fire detection method may further include a step of analyzing the filmed video when the fire occurs to detect the location of ignition within the filmed video; and a step of overlaying the flame sensitivity gauge around the location of ignition within the filmed video to generate the on-site surveillance video.

[0018] According to the present invention, flame sensing values ​​observed on-site are intuitively provided in the form of a flame sensitivity gauge within the captured images of network cameras installed around a surveillance area, thereby enabling managers to quickly recognize and respond in the event of a fire.

[0019] FIG. 1 is a drawing showing the configuration of a fire detection system using a flame sensitivity gauge according to an embodiment of the present invention.

[0020] Fig. 2 is a drawing showing an example of a flame detection sensor mounted on the network camera of Fig. 1.

[0021] Figure 3 is a drawing showing in detail the configuration of the network camera of Figure 1.

[0022] FIG. 4 is a drawing illustrating a rod-shaped flame sensitivity gauge according to an embodiment of the present invention.

[0023] FIG. 5 is a drawing showing an example of providing a flame sensitivity gauge at a designated location in a shooting image in an embodiment of the present invention.

[0024] FIG. 6 is a drawing illustrating a donut-shaped flame sensitivity gauge according to an embodiment of the present invention.

[0025] FIG. 7 is a drawing showing an example of providing a flame sensitivity gauge at a location where a fire occurs in a shooting image in an embodiment of the present invention.

[0026] FIG. 8 is a drawing illustrating a fire detection method using a flame sensitivity gauge according to an embodiment of the present invention.

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description have been omitted to clearly explain the present invention, and similar parts have been designated with similar drawing reference numerals throughout the specification.

[0028] Throughout the specification, when a part is said to be "connected" to another part, this includes not only the "direct connection" but also the "electrical connection" with other elements intervening between them. Furthermore, when a part is said to "include" a component, this does not exclude other components, but rather includes the possibility of including other components, unless otherwise stated.

[0029] The present invention relates to a fire detection system using a flame sensitivity gauge, and provides a fire detection system that allows a manager to intuitively check the state of flames at a surveillance target site through an image and a flame sensitivity gauge, thereby enabling a quick judgment and response to a fire situation.

[0030] FIG. 1 is a drawing showing the configuration of a fire detection system using a flame sensitivity gauge according to an embodiment of the present invention.

[0031] As shown in FIG. 1, a fire detection system according to an embodiment of the present invention includes at least one network camera (100), at least one flame detection sensor (120) mounted on the network camera (100), and a monitoring device (200).

[0032] Figure 1 shows an example of a network camera (100) and a flame detection sensor (120) being individually installed and operated at N sites. Here, a monitoring device (200) can receive video footage and a flame sensitivity gauge from the network camera (100) for each of the N sites, thereby simultaneously monitoring each site.

[0033] A network camera (100) is installed around the surveillance area to capture on-site video footage. The network camera (100) may incorporate a communication module (communication unit) for wired and wireless communication with a monitoring device (200). In addition, the network camera (100) is equipped with a flame detection sensor (120).

[0034] Fig. 2 is a drawing showing an example of a flame detection sensor mounted on the network camera of Fig. 1.

[0035] As shown in Fig. 2, the network camera (100) includes a camera lens (110), and at least one flame detection sensor (120) can be installed around the outer periphery of the camera lens (110). This flame detection sensor (120) can be built into the network camera (100) together with the camera lens (110).

[0036] The flame detection sensor (120) detects flames occurring on-site based on infrared rays. Specifically, the flame detection sensor (120) can detect flame intensity by filtering signals in the infrared wavelength band corresponding to flame components. At this time, the resistance value is measured differently depending on the intensity of the wavelength emitted from the flame, and from this, flame signal intensity detection is possible.

[0037] In general, when the flame sensing value observed using this principle is above a preset threshold, it can be recognized that a fire has occurred at the scene.

[0038] Here, since a signal with a wavelength similar to that of a flame exists even in normal air, the intensity of the flame can be detected even when no actual flame has occurred. However, since it is detected at a size weaker than the threshold for fire detection, it is not recognized as a fire outbreak.

[0039] The flame detection sensor (120) can be built into the network camera (100) as shown in FIG. 2, and the network camera (100) can receive the flame sensing value from the flame detection sensor (120) and transmit it in real time to the monitoring device (200) through the network together with the image captured by the camera sensor.

[0040] The monitoring device (200) can be connected to multiple network cameras (100) via a wired network, a wireless network, or a combined wired and wireless network, and can communicate with each other and transmit and receive data. Each network camera (100) can be individually installed and operated at a site surrounding the surveillance area, and the monitoring device (200) can be located near the site or in a remote location.

[0041] The monitoring device (200) can receive, store, and manage data including captured images, flame sensing values, flame sensitivity gauges, alarms, etc. in real time from each network camera (100) connected to the network. The monitoring device (200) can store and manage information regarding the camera ID, installation area information, jurisdiction, manager, flame detection sensor ID, etc. for each network camera (100), and can provide functions such as inquiry, registration, and modification of various types of information to administrators with access rights.

[0042] The monitoring device (200) may be located within the control center and may correspond to or be included in the management server equipped with the control sensor. The monitoring device (200) may receive various data in real time from the network camera (100) and display the received data on the screen.

[0043] The monitoring device (200) can simultaneously display multiple images observed from different sites on a single screen. For example, it can simultaneously provide images captured by multiple network cameras (100) through a split screen on a single display. In addition, the monitoring device (200) can receive on-site surveillance images in the form of a flame sensitivity gauge overlaid on the on-site images captured from the network camera (100) and display them in real time through an output means.

[0044] The output means may include a monitor, a large display panel, etc., and the administrator terminal may include a device that can connect to a wired or wireless network and exchange information, such as a PC, desktop, smart phone, tablet, or notebook.

[0045] In addition, the monitoring device (200) can provide on-site surveillance images, alarms, etc. through a separate network-connected display means, an administrator terminal, etc. Here, the display means and the administrator terminal, etc. can exist within the control center or be connected to the control center through a network.

[0046] FIG. 3 is a detailed diagram illustrating the configuration of the network camera of FIG. 1. As illustrated in FIG. 3, the network camera (110) includes an image acquisition unit (110), a flame detection sensor (120), a gauge generation unit (130), a control unit (150), and may further include an image analysis unit (140). Here, the control unit (150) can control the operation of each unit (110 to 140) and the data flow between each unit.

[0047] The image acquisition unit (110) acquires a video image of the surveillance area. The image acquisition unit (110) may include a camera sensor.

[0048] The flame detection sensor (120) can detect flames generated on site based on infrared rays and transmit the flame detection value observed in real time to the gauge generation unit (130).

[0049] The gauge generation unit (130) processes a flame sensitivity gauge using flame sensing values ​​sensed in real time from a flame detection sensor. The gauge generation unit (130) can transmit a flame sensitivity gauge that varies in real time according to the flame sensing values ​​to the control unit (150).

[0050] The control unit (150) transmits the field surveillance image generated by overlaying a flame sensitivity gauge on the shooting image in real time to a network-connected monitoring device (200).

[0051] Here, the control unit (150) can create a field surveillance image by overlaying a flame sensitivity gauge processed into a set shape (e.g., bar shape, circle) at a preset location within the shooting image, and provide this to the monitoring device (200) in real time.

[0052] Here, under the control of the control unit (150), the flame sensitivity gauge may be displayed at a predetermined location within the captured image (e.g., the lower right area within the image), or, in the case of an actual fire, may be displayed around the area where the actual fire occurred within the image.

[0053] The control unit (150) can compare the currently sensed flame sensing value with a preset threshold value, and if it is higher than the threshold value, recognize that a fire has occurred at the site and transmit a fire occurrence alarm to the monitoring device (200).

[0054] Accordingly, the monitoring device (200) outputs the on-site surveillance video received from the network camera (100) through an output means, and when a fire alarm is received, the fire alarm can be output together with the on-site surveillance video.

[0055] For example, when a fire alarm is received, the monitoring device (200) can provide a fire alarm by blinking the entire on-site surveillance video, and can also output a buzzer sound or the like to notify of a fire detection situation. Of course, the monitoring device (200) can also display a message notifying of a fire on the on-site surveillance video screen.

[0056] At this time, the flame sensitivity gauge can be continuously displayed on the captured video, regardless of whether a fire has occurred. Furthermore, when a fire is detected, the on-site surveillance video screen may flash for a set period of time or be disabled based on user input, set conditions, etc.

[0057] In addition, when a fire outbreak is detected in this way, the video analysis unit (140) can analyze the video captured by the network camera (100) to detect the actual location of fire within the video captured. At this time, the actual location of fire within the video can be detected by detecting features (color, shape, pattern) related to flames and smoke within the current video, or the location of fire (fire area) within the video can be detected by inputting the video into a pre-trained deep learning model.

[0058] In addition, in this way, in the event of a fire, the control unit (150) can generate an on-site surveillance image by overlaying the flame sensitivity gauge around the ignition location within the captured image. At this time, the displayed flame sensitivity gauge may have a donut shape.

[0059] Below, various embodiments of the flame sensitivity gauge are described through FIGS. 4 to 7.

[0060] FIG. 4 is a drawing illustrating a bar-shaped flame sensitivity gauge according to an embodiment of the present invention. FIG. 4 (a) illustrates a situation in which a current flame sensing value is detected to be below a threshold value, and FIG. 4 (b) illustrates a situation in which a fire occurs due to a current flame sensing value being detected to be above a threshold value.

[0061] As shown in Fig. 4, the gauge generation unit (130) can generate a flame sensitivity gauge composed of a bar-shaped gauge box (10-1) and a gauge bar (11) of a set color (e.g., red) whose length changes dynamically according to a flame sensing value within the gauge box (10-1).

[0062] Here, the gauge box (10-1) is divided into a first section (A) lower than the threshold value for a fire alarm and a second section (B) higher than the threshold value, and the first section (A) lower than the threshold value may have a different color (e.g., green) than the gauge bar (11). In this case, the red gauge bar (11) may be displayed overlapping the green area corresponding to the first section (A).

[0063] Additionally, the length of the gauge bar can increase upward within the gauge box. This can be confirmed through (b) of Fig. 4, which corresponds to a case where the flame sensing value is detected to be above the threshold value.

[0064] FIG. 5 is a diagram showing an example of providing a flame sensitivity gauge at a designated location within a captured image in an embodiment of the present invention. As shown in FIG. 5, the control unit (150) can generate an on-site surveillance image by combining a bar-shaped flame sensitivity gauge with a preset location within the captured image (e.g., the lower right corner of the screen).

[0065] In the case of an embodiment of the present invention, a bar-shaped flame sensitivity gauge may be provided at a predetermined location as shown in FIG. 4, but in the case of an actual fire occurring, a donut-shaped flame sensitivity gauge may be provided by displaying it around the location where the actual fire occurred in the image as shown in FIG. 6, which will be described later.

[0066] FIG. 6 is a diagram illustrating a donut-shaped flame sensitivity gauge according to an embodiment of the present invention. FIG. 6 (a) illustrates a situation in which a current flame sensing value is detected to be below a threshold value, and FIG. 6 (b) illustrates a situation in which a fire occurs due to a current flame sensing value being detected to be above a threshold value.

[0067] As shown in Fig. 6, the gauge generation unit (130) can generate a flame sensitivity gauge by using a curved gauge bar (11) of a set color (e.g., red) whose length changes dynamically according to the flame sensing value within the gauge box (10-2) in a donut shape.

[0068] Here, the gauge box (10-2) is divided into a first section (A) lower than the threshold value for a fire alarm and a second section (B) higher than the threshold value, and the first section (A) lower than the threshold value may have a different color (e.g., green) from the gauge bar (11). Since the gauge box (10-2) is shaped like a donut, the first section (A) and the second section (B) are divided into a semicircle shape based on the central threshold value. At this time, the red gauge bar (11) may be displayed by overlapping on the green area corresponding to the first section (A).

[0069] Additionally, the length of the gauge bar can increase clockwise within the gauge box. This can be confirmed through (b) of Fig. 6, which corresponds to a case where the flame sensing value is detected to be above the threshold value.

[0070] FIG. 7 is a diagram illustrating an example of providing a flame sensitivity gauge at a location of a fire outbreak within a captured image in accordance with an embodiment of the present invention. As shown in FIG. 7, the control unit (150) can generate an on-site surveillance image by attaching a donut-shaped flame sensitivity gauge around the actual location of ignition within the captured image when a fire occurs. At this time, by displaying the flame detection gauge on the side of the ignition location so as not to obscure the actual fire area, it is easy to identify the location of the fire as well as the fire situation.

[0071] Figure 8 is a drawing illustrating a fire detection method using a flame sensitivity gauge according to an embodiment of the present invention. This fire detection method can be performed by a network camera (100).

[0072] First, the network camera (100) acquires a video of the scene (S810), and then detects a flame occurring at the scene based on infrared rays using a flame detection sensor (120) installed in the network camera (100) (S820). These steps S810 to S820 can be performed simultaneously and in real time.

[0073] Next, the network camera (100) processes a flame sensitivity gauge using flame sensing values ​​collected in real time from a flame detection sensor (120) (S830).

[0074] Then, the network camera (100) overlays a flame sensitivity gauge on the captured image to create an on-site surveillance image and transmits it to the monitoring device (200) via the network (S840).

[0075] For example, as shown in Fig. 5, a bar-shaped flame sensitivity gauge can be overlaid on a designated area within a captured image. At this time, the gauge can move up and down in real time according to the flame detection value.

[0076] Here, the network camera (100) compares the current flame sensing value with a threshold value in real time, and if the flame sensing value is greater than the threshold value, recognizes an ignition situation and outputs a fire occurrence alarm and transmits it to the monitoring device (200) (S850).

[0077] In addition, when a fire situation occurs, the network camera (100) analyzes the captured video to detect the location of the fire within the video (S860).

[0078] In this case, the network camera (100) generates an on-site surveillance video in the form of a flame sensitivity gauge overlaid around the ignition location detected in the captured video and provides it to the monitoring device (200) (S870). For example, as shown in FIG. 7, a donut-shaped flame sensitivity gauge can be overlaid next to the actual fire occurrence area on the captured video. At this time, the gauge can move clockwise or counterclockwise in real time depending on the flame detection value.

[0079] According to this embodiment of the present invention, the flame sensing value observed on-site in the captured image of the network camera is intuitively provided in the form of a flame sensitivity gauge, thereby enabling the manager to quickly recognize when a fire occurs.

[0080] In addition, in the event of an actual fire, a flame sensitivity gauge is displayed around the location of the fire in the filmed video, allowing for quick assessment and response to the fire situation.

[0081] While the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary, and those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the appended claims.

Claims

1. In a network camera that provides a flame sensitivity gauge for the scene, An image acquisition unit that acquires video footage of the surveillance area; A flame detection sensor that detects flames generated on site based on infrared; A gauge generation unit that processes a flame sensitivity gauge using a flame sensing value sensed in real time from the flame detection sensor; and A network camera including a control unit that transmits in real time a field surveillance image generated by overlaying the flame sensitivity gauge on the above-mentioned shooting image to a network-connected monitoring device.

2. In claim 1, The above control unit, A network camera that generates the on-site surveillance video by overlaying the flame sensitivity gauge processed into a set shape at a preset location within the filmed video.

3. In claim 1, The above control unit, The currently sensed flame sensing value is compared with a threshold value, and if it is greater than the threshold value, it is recognized that a fire has occurred at the site and a fire occurrence alarm is transmitted to the monitoring device. The above monitoring device, A network camera that outputs on-site surveillance video received from the above network camera through an output means, and outputs the fire alarm together with the on-site surveillance video when the fire alarm is received.

4. In claim 2, The above gauge generating unit, Processing the flame sensitivity gauge, which is composed of a bar-shaped gauge box and a gauge bar of a set color whose length varies flexibly according to the flame sensing value within the gauge box, The above gauge box is divided into a first section lower than the threshold for a fire alarm and a second section higher than the threshold, wherein the first section has a different color from the gauge bar, A network camera in which the length of the above gauge bar increases upward within the above gauge box.

5. In claim 3, The above network camera, It further includes a video analysis unit that analyzes the above-mentioned video footage when the above-mentioned fire occurs and detects the location of ignition within the above-mentioned video footage. The above control unit, A network camera that generates the on-site surveillance video by overlaying the flame sensitivity gauge around the ignition location in the above-mentioned shooting video.

6. In claim 5, The above gauge generating unit, The flame sensitivity gauge is processed by forming a donut-shaped gauge box and a curved gauge bar of a set color whose length changes dynamically according to the flame sensing value within the gauge box. The above gauge box is divided into a first section lower than the threshold for a fire alarm and a second section higher than the threshold, wherein the first section has a different color from the gauge bar, A network camera in which the length of the above gauge bar increases clockwise within the above gauge box.

7. In a fire detection method performed by a network camera, Step of acquiring video footage of the surveillance area; A step of detecting a flame occurring on site based on infrared rays using a flame detection sensor installed in the above network camera; A step of processing a flame sensitivity gauge using a flame sensing value sensed in real time from the flame detection sensor; and A step of creating an on-site surveillance image by overlaying the flame sensitivity gauge on the above-mentioned shooting image; A step of transmitting the above-mentioned generated field surveillance video in real time to a network-connected monitoring device; and A fire detection method comprising a step of comparing the currently sensed flame sensing value with a threshold value, recognizing that a fire has occurred at the scene if the value is greater than the threshold value, and transmitting a fire occurrence alarm to the monitoring device.

8. In claim 7, The steps of generating the above on-site surveillance video are: A fire detection method for generating a scene surveillance image by overlaying the flame sensitivity gauge processed into a set shape at a preset location within the photographed image.

9. In claim 8, The steps of processing the above flame sensitivity gauge are: Processing the flame sensitivity gauge, which is composed of a bar-shaped gauge box and a gauge bar of a set color whose length varies flexibly according to the flame sensing value within the gauge box, The above gauge box is divided into a first section lower than the threshold for a fire alarm and a second section higher than the threshold, wherein the first section has a different color from the gauge bar, A fire detection method wherein the length of the above gauge bar increases upward within the above gauge box.

10. In claim 8, A step of analyzing the above-described video footage when the above-described fire occurs to detect the location of ignition within the above-described video footage; and A fire detection method further comprising the step of generating the on-site surveillance image by overlaying the flame sensitivity gauge around the ignition location in the above-described shooting image.

11. In claim 10, The steps of processing the above flame sensitivity gauge are: Processing the flame sensitivity gauge, which is composed of a donut-shaped gauge box and a curved gauge bar of a set color whose length varies flexibly according to the flame sensing value within the gauge box, The above gauge box is divided into a first section lower than the threshold for a fire alarm and a second section higher than the threshold, wherein the first section has a different color from the gauge bar, A fire detection method wherein the length of the above gauge bar increases clockwise within the above gauge box.

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