WO2018226128A1 - Video camera for the early detection of a wildfire - Google Patents

Abstract

The invention relates to video cameras for the early detection of a wildfire, comprising a housing with a rotating mechanism, an image capturing sensor and a lens. The rotating mechanism is capable of rotating and tilting and is equipped with an azimuthal goniometer connected to a controller. The azimuthal goniometer and the image capturing sensor are connected to a unit for transmitting data to a remote monitoring console. According to the invention, the sensor is connected to an image analysis module which is designed to be capable of identifying the signs of smoke and/or flame from a wildfire and is connected to a module for compressing an image stream. The technical result is to reduce the load on the remote monitoring console by virtue of transmitting a compressed image stream and the results of processing the signs of smoke and/or flame from a wildfire.

Description

 VIDEO CAMERAS FOR EARLY DETECTION

 NATURAL FIRE

The technical field to which the invention relates.

 The invention relates to the field of video surveillance, mainly open spaces, with fire hazard control, and specifically to video cameras for early detection of a natural fire, including a housing in which a rotary mechanism is located, on which an image capture matrix and a lens are mounted, while the rotary mechanism has the ability to rotate relative to the vertical axis and tilt and is equipped with a goniometer-azimuth meter connected to the controller for controlling the rotation and tilt of the image capture matrix moreover, the azimuthal azimuth meter and image capture matrix are connected to a data transmission unit for a remote monitoring station and can be used to detect forest fires when observing from high-rise structures.

 The following terms are used in this description:

 high-rise structure - a building, a tower, any structure much higher than the height of surrounding objects, allowing observation of the surrounding terrain;

 vertical - direction parallel to gravity;

 horizontal - direction perpendicular to gravity;

 tilt angle - the angle between the axis of rotation of the camera and the vertical; azimuthal angle of the video camera - the angle of orientation of the video camera relative to the north direction;

 calculated horizon line - the horizon line, which is calculated using a database of elevation maps of the topography based on the known height of the video camera;

 near-horizon - located near the horizon (since we are talking about the definition of fires, fires can be detected in the near zone, and in contrast to it in the far zone, near the horizon);

natural fire - an uncontrolled combustion process that spontaneously arises and spreads in the natural environment, is divided into forest and steppe fires; vector view - encoding images by setting the coordinates of vectors corresponding to the nodes of drawn objects;

 text view - encoding images by setting coordinates in text form corresponding to nodes of drawn objects.

The level of technology.

 A video camera for early detection of a natural fire is known from the prior art, including a housing in which a rotary mechanism is located, on which an image capture matrix and a lens are fixed, while the rotary mechanism has the ability to rotate about a vertical axis and tilt and is equipped with an azimuth meter connected to the controller rotation and tilt of the image capture matrix, and the azimuthal meter and image capture matrix are connected to the data transmission unit remote monitoring console, see patent specification N ° 2486594, published in 2013.

 This device is the closest in technical essence to the claimed invention and is taken as a prototype to the proposed invention.

 The disadvantage of this device is that it continuously receives terrain images and continuously transmits them to a remote monitoring console (server), on which the video image is processed. Since forests and fields occupy vast areas (especially in our country), dozens and hundreds of video cameras are used to monitor the terrain. When each of them continuously transmits data to a remote monitoring station, it has to process a huge array of data, which leads to the fact that the speed of detection of a natural fire decreases and the speed of response to a fire decreases. At the same time, the response speed is very important, since large areas of the forest can burn out for a short period of time.

For the correct recognition of signs of smoke and / or fire from a natural fire, it is necessary to transmit the data stream in an uncompressed form, since when it is compressed in a compressed form to a remote server corresponding to the remote monitoring console, the possibilities for image analysis and correct recognition of early signs of smoke and / or fire from a natural fire. Thus, the problem the solution to which the present solution is directed is the heavy load on the remote server, which performs many computational operations to determine a natural fire, since uncompressed data from many cameras is continuously being received on it.

Disclosure of the invention.

 Based on this original observation, the present invention mainly aims at providing a video camera for early detection of a natural fire, comprising a housing in which a rotary mechanism is located, on which an image capture matrix and a lens are fixed, while the rotary mechanism has the ability to rotate about a vertical axis and tilt and is equipped with a goniometer-azimuth meter connected to the controller for controlling the rotation and tilt of the image capture matrix, and goniometer-azimuth the meter and the image capture matrix are connected to the data transmission unit for the remote monitoring station, which allows at least mitigating the above drawback, namely, it is possible to reduce the load of the remote monitoring panel by transmitting a compressed image stream and the results of processing signs of smoke and / or fire from a natural fire , which is the technical task of the present invention.

 To achieve this, the image capture matrix is connected to an image analysis module, configured to detect smoke and / or fire from a natural fire, connected to an image stream compression module, the input of which is connected to the output of the image analysis module, and the output of which is connected to the transmission unit data to a remote monitoring station, while the image analysis module is configured to transmit the results of processing the signs of smoke and / or fire from a natural fire to a data transmission unit at Alain monitoring station.

Thanks to such advantageous characteristics, it becomes possible to directly recognize the data directly in the camcorder and send a compressed video signal and, optionally, a signal that contains information about a natural fire, that is, one that contains only the results of processing signs of smoke and / or fire from a natural fire . There is a possible embodiment of the invention in which the image analysis module includes a near-smoke analysis unit.

 Thanks to this advantageous characteristic, it becomes possible to analyze nearby fumes separately, since the algorithms for analyzing near fumes are based on the search for motion in the frame, a certain color and behavior.

 There is an embodiment of the invention in which the image analysis module includes an analysis unit of near-smoke.

 Thanks to such an advantageous characteristic, it becomes possible to analyze separately horizontal smoke, since the algorithms for analyzing near smoke are different, not based on the search for motion in the frame, and of a certain color - horizontal smoke in color matches clouds.

 There is a possible embodiment of the invention in which the image analysis module is configured to transmit the results of processing the signs of smoke and / or fire from a natural fire in vector or text form.

 Thanks to this advantageous characteristic, it becomes possible to additionally (in addition to transmitting a compressed video signal) transmit the results of processing signs of smoke and / or fire from a natural fire in vector or text form. It is clear that the transmission of such a signal does not lead to an increase in the flow of transmitted data, since, compared with video data, text or vector data occupy a volume that is orders of magnitude smaller.

 The set of essential features of the invention is unknown from the prior art for devices of similar purpose, which allows us to conclude that the criterion of "novelty" for the invention.

A brief description of the drawings.

 Other distinguishing features and advantages of the invention clearly follow from the description below for illustration and not being restrictive, with reference to the accompanying drawings, in which:

 - figure 1 schematically depicts a functional diagram of a video camera for early detection of a natural fire, according to the invention,

 - figure 2 depicts the steps of a video camera for early detection of a natural fire, according to the invention.

According to figure 1, the video camera for early detection of natural fire includes a housing 1, in which the rotary mechanism 2 is located, on which the image capture matrix 3 and the lens 4 are fixed. The rotary mechanism 2 has the possibility of rotation about the vertical axis 5 and tilt relative to the horizontal axis 6 and is equipped with an azimuth-meter 7 connected to the controller 8 of the rotation and tilt control of the image capture matrix 3. The azimuthal azimuth meter 7 and the image capture matrix 3 are connected to the data transmission unit 9 to the remote monitoring console 10.

 The image capture matrix 3 is connected to an image analysis module 1 1, configured to detect smoke and / or fire from a natural fire, connected to an image stream compression module 12, the input of which is connected to the output of the image analysis module, and the output of which is connected to block 9 transmitting data to a remote monitoring station 10.

 The image analysis module 1 1 is configured to transmit the results of processing smoke and / or fire signs from a natural fire to a data transmission unit to a remote monitoring console

 The transmission unit 9 for transmitting data to a remote monitoring station 10 can transmit signals over the air or, for example, over the Internet.

 The image analysis module 1 1 mainly includes a near smoke analysis unit 13.

 The image analysis module 1 1 advantageously includes a smoke analysis unit 14.

 The figure 1 also indicated:

 15 - high-rise structure,

 g is the vector of gravity.

 The camcorder may have an anti-fog filter and a unit for cleaning the lens / dome from raindrops. The figures are not shown.

The implementation of the invention.

 A video camera for early detection of a natural fire is used as follows. (A non-limiting example of use is provided). According to FIG. 2:

Stage A1. Installation A video camera having a rotary mechanism 2 is mounted on a high-rise structure, on which an image capturing matrix 3 and a lens 4 are fixed. Stage A2. Snapping. The exact coordinates of the camera and the height of its suspension are determined. The coordinates of the video camera are specified according to several sources of orthophotomaps - Google maps, Yandex maps, etc. Thus, it becomes possible to bind the coordinates of the installation of the camera - up to a meter.

 Stage A3. Correction of the angle of rotation. Calculate the correction of the azimuth of the camera’s rotation relative to the north direction by comparing the direction to a visible landmark.

 Stage A4. Tilt Correction. The correction of the angle of the camera relative to the horizon is calculated.

 Stage A5. Shooting. Survey the territory by sequentially turning the turntable around a vertical axis. To do this, determine the optimal viewing time for the patrol route of the territory and the sufficiency of time to analyze the scene, the viewing angle, for example: 6 degrees horizontally and 10-12 minutes for a full revolution of the camera around its axis. Moreover, the analysis of the scene at each stopping point takes from 10 to 15 seconds.

 Stage A6. Image analysis.

 Using the module 1 1 image analysis, configured to determine the signs of smoke from a natural fire, analyze the resulting image.

 To do this, divide the observed scene into sections:

 - above the horizon (there are clouds in this zone and recognition is not performed in this area)

 - horizontal zone (distances from the camera installation point from 8 to 12 km)

 - near zone (from 1 to 8 km).

 Stage A61. In the near zone, recognition is performed using the near-smoke analysis unit 13. The classic algorithm works here - enough information about the movement in the frame.

Stage A62. In the analyzed near-horizon area, recognition is performed using the block 13 analysis of horizontal smoke. For this, for example, isolines are constructed in the analyzed horizontal region, enveloping the pixels of the image combined in color, brightness and contrast into segments. The lines that outline such segments are contours (lines between areas with similar color, brightness, and contrast). From many contours the longest contour is selected containing the portion with the greatest deviation from the horizon, which is substantially shorter in horizontal dimension than the horizon. Pixels are analyzed in the area of the frame bounded by the portion of the selected contour with the greatest deviation from equal distance from the horizon for similarity in color with smoke. If there is a deviation of the contour section from an equal distance from the horizon, the possibility of a natural fire is fixed in the place corresponding to the specified one, and if there is a contour that repeats the shape of the horizon, the absence of a natural fire in the near-horizon region is recorded.

 Stage A7. Compress and transfer the recognized image.

 The image is always compressed using module 12 and transmitted in compressed form using block 9 to the remote control 10. It is this that significantly reduces the load on the equipment of the remote control and reduces the requirements for data transmission channels.

 But since it is impossible to qualitatively recognize features corresponding to the possibility of a natural fire on the remote control, since the video signal is transmitted compressed, the results of data analysis from the device are additionally transmitted for this. That is, when a situation arises when the signs corresponding to the potential of a natural fire are recognized, the image analysis module 1 1 generates data corresponding to the results of processing the signs of smoke and / or fire from a natural fire, and it is they that are transmitted through the data transmission unit 9 to a remote monitoring console 10.

 The above embodiments of the invention are exemplary and allow you to add new options or modify the described without losing the possibility of early detection of natural fires.

Industrial applicability.

A video camera for early detection of a natural fire can be carried out by a specialist in practice and, when implemented, ensures the implementation of the declared purpose. The possibility of practical implementation follows from the fact that for each feature included in the claims on the basis of the description, the material equivalent is known, which allows us to conclude that the criterion of "industrial applicability" for the invention and the criterion of "completeness of disclosure" for the invention are met. In accordance with the proposed solution, the applicants produced a prototype video camera for the early detection of a natural fire, which was made on the basis of the AXIS network PTZ dome camera.

 Tests of the prototype showed that it becomes possible to provide image recognition from the matrix for signs of natural fire (smoke traces), and to transmit to the remote monitoring station a compressed signal, and one that contains information about the signs of fire in case of occurrence, as well as information about the angle of inclination and the azimuthal angle of the matrix of the camera.

 All this ultimately ensures the achievement of the technical result achieved - the ability to reduce the load of the remote monitoring console by transmitting a compressed image stream and the processing of signs of smoke and / or fire from a natural fire.

 Example.

 The received parameters of the transmitted signal after its "compression":

 H.264 8 fps GOP 32 with 30% reference frame compression:

D1 (704 ^* 576) - 300 Kbps

720p (1280 ^* 720) - 512 Kbps

1080p (1920 ^* 1080) - 800 Kbps

 It has been verified that with such characteristics, the picture does not “fall apart” and is easy to read, while the transmission speeds are low, which allows significant savings on communication services.

 For comparison, for video processing on the server side, reference frames must be transmitted without compression, that is, H.264, these are frames per second 8 and GOP 32, but without compression of each individual frame, which gives the following data transfer parameters:

720p (1280 ^* 720) - 8192 Kbps

 Flow rates are indicated for normal illumination (at night there are a lot of digital noise, which means more movement, so the load is growing) and at a wind speed of 1-3 m / s (at high wind speeds, the forest moves more).

 It can be seen that the difference is: - 10-30 times.

Claims

FORMULA OF THE INVENTION one . A video camera for early detection of a natural fire, comprising a housing in which a rotary mechanism is located on which an image capture matrix and a lens are mounted, while the rotary mechanism has the ability to rotate about a vertical axis and tilt and is equipped with an azimuth meter connected to the rotation control controller and the slope of the image capture matrix, and the azimuth meter and image capture matrix are connected to the data transmission unit to the remote monitoring station characterized in that the image capture matrix is connected to an image analysis module configured to detect smoke and / or fire from a natural fire, connected to an image stream compression module, the input of which is connected to the output of the image analysis module, and the output of which is connected to the transmission unit data to a remote monitoring station, while the image analysis module is configured to transmit the results of processing the signs of smoke and / or fire from a natural fire to a data transmission unit for removal enny monitoring station.  2. The video camera according to claim 1, characterized in that the image analysis module includes a near-smoke analysis unit.  3. The video camera according to claim 1, characterized in that the image analysis module includes a block analysis of horizontal smoke.  4. The video camera according to claim 1, characterized in that the image analysis module is configured to transmit the results of processing signs of smoke and / or fire from a natural fire in vector or text form.