Device for a premises security monitoring system installation including an image capture arrangement

Abstract

Provided is a method performed by an image capture arrangement device, the method comprising the steps of: i) monitoring a monitored area; ii) in response to the detection of presence within the monitored area, capturing images of the monitored area; iii) temporarily storing the images on the device; and iv) starting a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from a controller of a security monitoring system a notification in respect of the temporarily stored images; and iv) in the event of receiving notification from the controller of the security monitoring system in respect of a security event, transmitting to the controller of the security monitoring system temporarily stored images. A corresponding device, and an installation including the device, are also provided.

Description

[0001] Device for a premises security monitoring system installation including an image capture arrangement.

[0002] Technical field

[0003] The present invention relates to a device for a premises security monitoring system, the device including an image capture arrangement, premises security monitoring systems including such a device, and corresponding methods.

[0004] The EU General Data Protection Regulation (GDPR) regulates data protection and privacy for individuals, and since its adoption in 2016 has served as a model for similar legislation in many countries outside Europe. The GDPR applies to the processing of “personal data” which is defined very broadly as “any information relating to an identified or identifiable natural person (‘data subject’); an identifiable natural person is one who can be identified, directly or indirectly, in particular by reference to an identifier such as a name, an identification number, location data, an online identifier or to one or more factors specific to the physical, physiological, genetic, mental, economic, cultural or social identity of that natural person”. Included within this definition are images, such as photographs and video relating to an identified or identifiable natural person. The Regulation does not apply to the processing of personal data “by a natural person in the course of a purely personal or household activity”, and on this basis it is believed that the capture and (local) storage of images from domestic security systems may be outside the scope of the Regulation. However, if the images captured are of individuals not on the property or premises protected by the domestic security systems - for example if the images include people on the street or in communal areas of a multi-occupancy building, then the captured images are likely to be subject to the Regulation. This poses a potential problem for the owners / users of domestic security systems and, for example, video doorbell installations. In the UK this issue came to prominence in 2021 when a dispute between neighbours over the installation of a domestic security system and a Ring (RTM) doorbell went to Court, resulting in the neighbour with the security system being found to have breached the GDPR and liable for a substantial fine and damages.

[0005] Video doorbells and domestic security systems continue to increase in popularity, despite the risk of (inadvertently) breaching the GDPR (or the local equivalent outside Europe). There therefore exists a need to provide safeguards to reduce the risk of inadvertently breaching the GDPR or other equivalent legislations by installing and operating domestic security monitoring systems and / or video doorbells.

[0006] Where an image capture device, which may for example be a security camera for a security monitoring system, a video doorbell, or an access device, is installed on the facade of premises and / or at a main entrance door of the premises the proportion of a captured image that is devoted to the protected property shrinks significantly the closer to the street or other public space the premises are located. For example, for a house with extensive private grounds - where the front of the house is say 8 metres from the public space much more than 50% (maybe 75 - 80% or more) of a captured image may cover the private grounds, with much less than 50% ( e.g. 25-30% covering the public space. Whereas with a dwelling where the front of the premises is between 3 and 5 metres from the public space an image capture arrangement may capture images in which much less than 50% of an image represents the private space - e.g. 25-30%, with the balance given over to public space and possibly sky. Finally, with a dwelling where the front of the premises less than about 3 from the public space an image capture arrangement may capture images in which very little or even none of an image represents the private space - e.g. 10% or less, with the balance given over to public space and possibly sky. It will thus be appreciated that for the latter types of installation it may be essentially impossible to capture useful images that are not largely made up of public space and hence potentially very problematic from a GDPR and data privacy perspective. Nevertheless, customers still want to use video doorbells, security cameras, access devices and the like to capture images relevant to actual or potential security breaches - thus presenting a dilemma between the requirements for data privacy, as exemplified by the GDPR, and the desire for the enhanced personal security potentially provided by a premises security monitoring installation.

[0007] Embodiments of the present invention seek to provide solutions addressing aspects of these issues.

[0008] Summary

[0009] According to a first aspect there is provided a device for a premises security monitoring system installation, the device including an image capture arrangement arranged to monitor a monitored area, the image capture arrangement device including presence detection means to detect presence within the monitored area, and the image capture arrangement being configured to: i) capture images of the monitored area responsive to the detection of presence within the monitored area; ii) temporarily store the images on the device; and iii) start a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from the controller of the security monitoring system a notification. According to a second aspect there is provided a premises security monitoring system installation including a controller and a plurality of sensors, operatively connected to the controller, for the detection of security events, the installation comprising a device including an image capture arrangement arranged to monitor a monitored area, the image capture arrangement device including presence detection means to detect presence within the monitored area, and the image capture arrangement being configured to: i) capture images of the monitored area responsive to the detection of presence within the monitored area; ii) temporarily store the images on the device; and iii) start a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from the controller of the security monitoring system a notification; the controller of the security monitoring system being configured, in the event of receiving notification of a security event, to communicate with the image capture arrangement for the image capture arrangement device to transmit to the controller temporarily stored images.

[0010] In such an installation or device upon expiry of the timer captured images may be deleted in the sense that the image data are made unavailable for future access, for example by one or more of the following: overwriting, removing directory information for the file, deleting an encryption key with which the data are encrypted.

[0011] In an installation according to any variant of the second aspect the controller of the security monitoring system may be configured to: report a notified security event to a remote monitoring centre; and make available to the remote monitoring centre images received from the image capture arrangement device.

[0012] In an installation according to any variant of the second aspect the controller of the security monitoring system may be further configured to cause the image capture arrangement device to continue to capture and supply images of the monitored area.

[0013] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the image capture arrangement device may be configured to capture images of the monitored area only in response to the detection of presence exceeding a duration of at least several seconds, optionally at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30 or more seconds.

[0014] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of presence within a near field zone of the monitored area, optionally the near field zone extending no more than 3 metres from the device, optionally no more than 2.5 metres from the device, optionally no more than 2 metres of the device, optionally no more than 1.8 metres of the device, optionally no more than 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, or 1 metres from the device.

[0015] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement within the monitored area, optionally movement towards the device.

[0016] In a device according to any variant of the first aspect or an installation the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement towards a point of entry to premises protected by the security monitoring installation.

[0017] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the images may be video images with or without sound.

[0018] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the images may be still images.

[0019] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the timer may have a duration of no more than 30 minutes, optionally no more than 25, 20, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or 4 minutes.

[0020] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the image capture arrangement device may be configured to reset the timer if, before expiry of the timer, presence is again detected following a period in which no presence was detected.

[0021] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect image data of captured images may be held in the device in an encrypted form.

[0022] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the image capture arrangement device may be configured to encrypt image data of captured images before the data are shared between the image capture arrangement device and the controller.

[0023] In a device according to any variant of the first aspect or an installation according to any variant of the second aspect the image capture arrangement device may be configured as one or more of a video doorbell device, an access device for the security monitoring system, or a security camera of the security monitoring system. According to a third aspect there is provided a method performed by an image capture arrangement device, the method comprising the steps of: i) monitoring a monitored area; ii) in response to the detection of presence within the monitored area, capturing images of the monitored area; iii) temporarily storing the images on the device; and iv) starting a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from a controller of a security monitoring system a notification in respect of the temporarily stored images.

[0024] Optionally ,in the event of receiving notification from the controller of the security monitoring system in respect of a security event, the method further comprises transmitting to the controller of the security monitoring system temporarily stored images.

[0025] In such methods, upon expiry of the timer, captured images may be deleted in the sense that the image data are made unavailable for future access, for example by one or more of the following: overwriting, removing directory information for the file, deleting an encryption key with which the data are encrypted.

[0026] In a method according to any variant of the third aspect the image capture arrangement device is configured to capture images of the monitored area only in response to the detection of presence exceeding a duration of at least several seconds, optionally at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20, 25, 30 or more seconds.

[0027] In a method according to any variant of the third aspect the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of presence within a near field zone of the monitored area, optionally the near field zone extending no more than 3 metres from the device, optionally no more than 2.5 metres from the device, optionally no more than 2 metres of the device, optionally no more than 1.8 metres of the device, optionally no more than 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, or 1 metres from the device.

[0028] In a method according to any variant of the third aspect the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement within the monitored area, optionally movement towards the device.

[0029] In a method according to any variant of the third aspect the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement towards a point of entry to premises protected by the security monitoring installation.

[0030] In a method according to any variant of the third aspect the timer may have a duration of no more than 30 minutes, optionally no more than 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or 4 minutes. In a method according to any variant of the third aspect the image capture arrangement device may be configured to reset the timer if, before expiry of the timer, presence is again detected following a period in which no presence was detected.

[0031] According to a fourth aspect there is provided a premises security monitoring system installation including a controller and a plurality of sensors, operatively connected to the controller, for the detection of security events, the installation comprising a device according to variant of the first aspect, the controller of the security monitoring system being configured, in the event of receiving notification of a security event, to communicate with the device for the device to transmit to the controller temporarily stored images

[0032] Optionally, in such an installation, the controller of the security monitoring system may be configured to: report a notified security event to a remote monitoring centre; and make available to the remote monitoring centre images received from the image capture arrangement device.

[0033] Optionally, in an installation according to any variant of the fourth aspect, the controller of the security monitoring system may be further configured to cause the device to continue to capture and supply images of the monitored area.

[0034] An image capture arrangement device may be configured to perform the method according to any variant of the third aspect. Such an image capture arrangement device may be in the form of a video doorbell or access device for the security monitoring system, and be configured to respond to a physical interaction with a person by capturing and retaining on the device images of the person involved in the interaction. Such an image capture arrangement device may further be configured to upload to the controller of the security monitoring system images of the interaction. Such an image capture arrangement device may further be configured to upload to the controller of the security monitoring system images of the interaction only in response to an instruction from the controller of the security monitoring system.

[0035] Brief description of Figures

[0036] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying Figures, in which:

[0037] Figure 1 shows a view of the front of a premises 100 protected by a security monitoring system according to an aspect of the present invention.;

[0038] Figure 2 is a schematic part plan view of a premises 100 protected by security monitoring system according to an aspect of the invention;

[0039] Figure 3 illustrates schematically the major components of an image capture arrangement according to an aspect of the invention in the form of a video doorbell or access device; Figure 4 is a plan view of the grounds of the premises of Figure 1 showing the relationship between the house and its environment;

[0040] Figure 5 shows a potential view from the video doorbell installed on the premises of Figures 1, 2 and 4;

[0041] Figure 6 illustrates schematically examples of images provided by image capture devices according to aspects of the invention installed at premises with differing amounts of private property in front of the premises; and

[0042] Figure 7 corresponds to Figure 5 but illustrates presence adjacent the protected premises as well as in a public area beyond a private garden of the protected premises.

[0043] Specific description

[0044] Figure 1 shows a view of the front of a premises 100 protected by a security monitoring system according to an aspect of the present invention. The premises, here in the form of a house, have an exterior door, here front door, 102. The door gives access to a protected interior space. The security monitoring system secures at least part of a perimeter to the premises 100, and the door constitutes an exterior closure 102 in the secure perimeter giving access to a protected interior space 200 of the premises. A lock 104 on the exterior door is optionally electrically controlled so that it can be locked and unlocked remotely.

[0045] To the side of the door, on the facade of the house, is a first video camera in the form of a video doorbell 106 which looks out from the facade of the premises so that anyone approaching the door along the path 108 can be seen, and in particular when a visitor stands at the door their face should clearly be visible. The video doorbell includes an actuator, e.g. a push button (or an arrangement that emulates a push button, such as a capacitance sensor responsive to human touch), for a visitor to indicate their presence at the closure. The video doorbell also includes an audio interface to enable bidirectional audio communication with a visitor at the closure 102.

[0046] As is conventional, the video doorbell preferably includes an infrared light source to illuminate whatever is in front of the video doorbell. Optionally, as shown, the facade of the house also carries an external keypad (aka “access device”) 110 by means of which a user can disarm the security monitoring system, and unlock the lock 104. Also shown is an optional second video camera 112 which is coupled to a presence and / or movement detector 114. The detector may optionally be a thermal detector, for example a PIR sensor. The second video camera 112 may be arranged when the security monitoring system is armed, to capture video of the approach to the house and / or the private area, e.g. the garden, to the front or the car-parking space 120 to the side of the house and signal an alarm event to a controller of the security monitoring system. As with the doorbell camera, the second video camera is preferably provided with an audio interface to enable bidirectional audio communication with anyone observed by the second video camera. Although the first video camera is illustrated in the form of a video doorbell, the first video camera may additionally or alternatively have the features described above for the second video camera, whether or not plural video cameras are used.

[0047] Figure 2 is a schematic part plan view of a premises 100 protected by security monitoring system according to an aspect of the invention, together with other elements of the system, corresponding generally to the premises of figure 1. The front door 102, with electrically controlled lock 104, leads into the protected interior space 200 of the premises. Each of the windows 202, and the rear door 204 is fitted with a sensor 206 to detect when they are opened. Each of the sensors 206 includes a radio transceiver to report events to a controller , or central unit, 208 of the security monitoring system. If one of the sensors 206 is triggered when the system is armed, a signal is sent to the central unit 208 which in turn may signal an alarm event to a remote central monitoring station 210. The central unit 208 is connected to the remote central monitoring station 210 via the Internet 212, either via a wired or a wireless connection. Also wirelessly coupled to the central unit 208 are the video doorbell 106, the electrically controlled lock 104, and if present the second video camera 112, its associated presence and / or movement detector 114 (although the latter may be integral with the second video camera 112) and the audio interface 116. These items, and the sensors 206, are preferably coupled to the central unit 208 using transceivers operating in the industrial scientific and medical (ISM) bandwidths, for example a sub-gigahertz bandwidth such as 868 MHz, and the communications are encrypted preferably using shared secret keys. Preferably the central unit 208 and each image source (e.g. video camera, other camera, or video doorbell) also includes a transceiver to provide Wi-Fi connectivity, e.g. for the sharing of images and video as timely transmission of image and video files requires a relatively large bandwidth, at least for the kinds of high resolution images which are typically wanted in security monitoring installations. Preferably the Wi-Fi or other large bandwidth transceiver is provided in addition to the low-bandwidth transceiver (e.g. ISM transceiver) used for the transmission and reception of control signals and event notifications and the like. The security monitoring system may also include other sensors within the protected interior space, such as an interior video camera 214 and associated movement detector 216 (which again may be integral with the camera 214), and each of the interior doors 218 may also be provided with a sensor 206 to detect the opening / closing of the door. Also shown in figure 2 are a user device 220, preferably loaded with an appropriate app - as will be described later, and a public land mobile network (PLMN) by means of which the central monitoring station 210, and the central unit 208, may communicate with the user device 220.

[0048] Operation of the security monitoring system may be controlled by one or more of: the controller 208, the remote monitoring station 210, and a security monitoring app installed on the user device 220. An access device 110 may be provided outside the protected premises, e.g. on an exterior wall of the premises, optionally adjacent a main entrance, such as the front door 102, to enable an occupier to arm and disarm the security monitoring system and optionally also to lock and unlock a lock (e.g. 104) in the relevant door, e.g. to gain admittance to the premises.

[0049] The remote monitoring station 210, if provided, may receive one or more signals from any of the first camera and / or video doorbell 106, the second camera 112, the keypad 110, the sensors 206 and / or 520 (described in more detail later). The remote monitoring station 210 may transmit commands for controlling any one or more of: the arm state of the alarm system (e.g. armed or unarmed); commanding a tripped alarm state to be signalled by the alarm system (e.g. by triggering one or more sirens to generate alarm noise); commanding a lock state of the door lock 104 (e.g. locked or unlocked), commanding operation of one or more functions of the video doorbell 106, commanding operation of one or more cameras to transmit images to the remote monitoring unit. Communication with the remote monitoring station 210 may pass through the controller 208, as described above. In other embodiments without the remote monitoring station 210, or in the event that communication with the remote monitoring station 210 is interrupted, operation of the alarm system may be controlled by the controller 208. In yet other embodiments, the controller 208 may be omitted, and the individual peripheral devices may communicate directly with the remote monitoring station 210.

[0050] The security monitoring system app is installed on a user device 220, here shown as a smartphone, although of course it could be almost any kind of electronic device, such as a laptop or desktop computer, a tablet such as an iPad, a smart watch, or even a television.

[0051] Having set the scene for the invention, we will now consider an approach according to aspects of the invention that can help satisfy the requirements for data privacy, as exemplified by the GDPR, and the desire for the enhanced personal security potentially provided by a premises security monitoring installation.

[0052] Figure 3 illustrates schematically the major components of an image capture arrangement 300 in the form of a video doorbell, for example a doorbell 106 as shown in Figure 1 and 2. A processing arrangement 302 (hereinafter “processor”), which may be an MCU, a microprocessor or a collection of processors or more than one MCU, is coupled to an image sensor 304, here in the form of a video camera, a low power and / or thermal sensor 306 which may for example be a thermal sensor for detecting presence e.g. by detecting motion. Also coupled to the processor 302 is an optional ranging arrangement 308, for example a radar arrangement or a time of flight sensing arrangement, although ranging information may alternatively be derived from analysis of images captured by the image sensor 304. Time of flight ranging is typically based on the use of short transmitted pulses, for example, light pulses from a laser or LED, or ultrasound pulses. The processor 302 is also coupled to one or more RF transceiver(s) 310 (for example a transceiver to support the rapid transmission of large image files, e.g. a Wi-Fi transceiver, and a narrow bandwidth transceiver (e.g. a ISM transceiver) for transmitting and receiving notifications and control messages, etc), a memory 312 that stores software to control the operations of the processor 302 and also stores images / video captured by the image sensor 304 and any audio captured by the microphone, a power supply unit 314 (which preferably includes one or more batteries to at least provide backup in the event of failure of any mains-fed power supply - although the power supply may instead be based on battery power rather than on mains-fed power), an audio interface 316, and preferably also a lighting arrangement 318 that at least provides infra-red illumination to enable images to be captured in the absence of significant levels of visible light. These elements are preferably also provided in image capture arrangements other than video doorbells, for example they may all be provided in a video camera of a security monitoring system such as that shown as camera 112 in Figures 1 and 2. Additionally, when the image capture arrangement of Figure 3 is a video doorbell it further comprises an actuator 320 - a “bell push” which may be in the form of a mechanical switch or in the form of an actuation device that detects user input using one or more capacitive or inductive sensors and that preferably does not rely on moving parts to detect an activation event. Again, when the image capture arrangement of Figure 3 is a video doorbell, the image capture arrangement of Figure 3 may further comprise a display 322 for the display of messages and visual feedback.

[0053] The elements shown in Figure 3 also largely correspond to those provided in an access device such as 110, although in this case a keypad 321 may be provided in place of, or in addition to, the actuator 320. Again, the ranging arrangement 308 is optional.

[0054] Before explaining the operation of the image capture arrangement of Figure 3 we will develop the potential context of its use with reference to Figure 4. Figure 4 is a plan view of the premises 100 of Figure 1 showing the relationship of the house, and its private grounds, to a street 400 and a neighbouring house 101. The video doorbell 106 is mounted on the facade of the house 100 and therefore looks out over the path 108, driveway 109, the garden walls 400, and through the entranceway 402 to the street 404 and the footpaths 406 and 408 of the street - as indicated by the dashed lines 410. Similarly, the video camera 112 installed to monitor the car parking space 120 and adjacent portions of the garden also provides a view into the neighbouring garden as indicated generally by the dashed lines 412. It will be appreciated that these video cameras are installed to monitor a specific area of interest - which may also be referred to as the target zone. In the case of the video doorbell the monitored area comprises a specific area of interest 414 that includes the area between the front of the house and the walls 400 and the entrance gateway, including the path 108 and the driveway. But in addition, the monitored area includes those portions of the street and footpaths visible through the gateway even though these areas he outside the specific area of interest. Likewise, although the video camera 112 is provided to monitor the parking space 120 and adjacent garden, in fact the monitored area extends to include a large portion of the neighbour’s property even though the neighbour’s property is private and lies outside the specific area of interest 416. In the case of the video doorbell 106 in particular a distinction may be made between different zones within the specific area of interest 414. For example a near field zone may be defined to be within 1 to 1.5 metres of the video doorbell, the near field zone defining the zone where a visitor may stand while waiting for a rung doorbell to be answered, for example. The remainder of the specific area of interest 414 may constitute a single “far field” zone or be divided into two or more further zones - e.g. a medium field zone and a far field zone, and possibly additionally or alternatively also laterally divided into multiple regions.

[0055] Returning to Figure 3, at a high level the image capture arrangement 300 comprises a processor 302, and coupled to the processor 302: an image sensor 304 to capture images of a monitored area; a low power and / or thermal sensor 306, such as a thermal sensor, to detect human presence in the monitored area; and an optional range determining arrangement 308, for example a radar arrangement. The sensor 306 is a presence sensor preferably with a low power consumption - for example a lower power consumption than either the range detecting arrangement and / or the image sensor, and / or the processor when processing images. The sensor 306 may detect presence based on detecting motion or simply based on detection of presence without the need for motion. Such presence, with or without motion, may be detected by thermal sensors, and in general thermal sensors can be expected to have suitably low power consumption for this application. For example, the sensor 306 may be a PIR (passive infrared) sensor which detects motion by detecting changes in infrared radiation, or optionally a TMOS sensor which senses absolute temperature (rather than a differential temperature as a PIR does). Typically a high quality PIR sensor will consume less than O.OlmW, e.g. 0.005mW, while a TMOS sensor may consume no more than about 0.05mW. Depending on the desired implementation, an advantage of a TMOS sensor over a PIR sensor is that the TMOS sensor is generally harder for an intruder to fool because unlike a PIR sensor it does not rely on detecting motion - an advantage that stems from the fact that the TMOS sensor responds to absolute temperature. Also, over ranges likely to be of interest in the present application, TMOS sensors may not need to be provided with associated optics which is advantageous in terms of both cost and size, although optics may be provided if desired. While other types of presence sensing are available, for example based on the use of ultrasound or based on modulation of light from a powered light source, typically such sensing arrangements may consume too much power for this application. Hereafter, the terms low power sensor and thermal sensor may be used interchangeably. The low power sensor is preferably always active (“always on”), which at least in part explains why we want to use a sensing arrangement having a low power consumption. We want the low power sensor to have a power consumption lower, and preferably much lower, than that of the range detecting arrangement if used because we may use signals from the low power sensor as a trigger to activate the range detecting arrangement that is usually off. Ranging signals from the range detecting arrangement, if present, may be used to determine whether or not there is presence within the specific area of interest of a camera, so that the camera can be turned on only when there is presence within the camera’s specific area of interest (unless it is decided to turn on the camera - more generally image sensor - for some other reason, for example on instruction from the remote monitoring station 210).

[0056] The range detecting arrangement may, for example, comprise a radar arrangement, for example, a low power radar arrangement. A low power radar arrangement may have a power consumption of less than about 200mW, optionally less than about lOOmW, optionally less than about 50mW, optionally less than about 25mW. A radar arrangement can provide range information including distance and direction to a detected target. Additionally or alternatively, the range detecting arrangement may comprise a so called time-of-flight sensor, for example, an ultrasonic time-of-flight sensor, or a light-based time-of-flight sensor comprising, for example, a laser or an LED. Such a sensor may provide distance and / or movement information, optionally without direction. However, a time-of-flight sensor may be more power efficient and / or cost efficient than a radar arrangement.

[0057] The image capture arrangement may be so configured that in a rest state the image sensor 304 and the ranging arrangement are powered down, to save energy, and the processor may be configured in at least one operating mode to respond to a signal from the thermal sensor 306 that indicates human presence in the monitored area by powering up the ranging arrangement to determine the range of any human presence within the monitored area. The image sensor 304 has associated optics, not shown, for focusing light onto the image sensor, and may take the form of a camera module that includes dedicated processing and other features (e.g. memory) useful in a camera module, but equally the image sensor and optics may work in conjunction with the processor 302 and memory 312 to provide the functionality of a camera. In either format, the image capture arrangement is preferably configured to capture video as well as individual still images. Preferably there is also provided at least one microphone to capture audio, for example along with any video captures. The processor may further be configured in the at least one operating mode to activate the image sensor only if information received from the ranging arrangement indicates presence within a target zone within the monitored area.

[0058] Any radar arrangement may conveniently operate in the 60Ghz band, where low power consumption system on chip solutions are available in very compact packages (for example, where the antennas are provided “on package” rather than as external components) from the likes of Infineon, Texas Instruments, and Socionext. Suitable devices include the BGT60LR11AIP device from Infineon, and the IWRL64322 from TI. Although these devices have surprisingly low power consumption, power savings can be made, and hence device battery life extended, by using a presence detector with a lower power consumption than the radar ( hence the use of the expression “low power sensor”) to monitor the monitored area while having the radar sleep. The lower power consumption presence detector may use for example a thermal sensor (IR sensing) such as a PIR sensor or a TMOS sensor to detect presence in the monitored area. TMOS sensors are particularly preferred because they sense absolute temperature rather than differential temperature as PIR sensors do, and this means that TMOS sensors are capable of detecting stationary objects as well as moving ones. TMOS sensors can also detect human-sized objects at up to 6 metres distance without the need to use optics, and up to 12 metres if suitable optics are used. Suitable TMOS sensors are available from ST Microelectronics - for example the STHS34PF80 device. Upon receiving a “presence” signal from the low power sensor 306, the processor can wake the ranging arrangement to obtain a ranging signal which can be used to determine whether the presence is within the desired “target zone”. If the presence is, for example too far away to be of interest, the processor doesn’t wake the image sensor , but if the presence is within the target zone the image sensor is activated and images of whoever or whatever is in the target zone are captured.

[0059] Defocusing energy received from ground level can help a PIR to distinguish between human and animal presence in that thermal energy is then received primarily from standing objects, rather than ground-level animals.

[0060] Image processing can use image recognition or pattern matching to detect human forms in the image.

[0061] From considering Figure 4 it will be appreciated that the image sensor may (and generally will) have a larger field of view than the low power sensor 306 and / or the ranging arrangement 308. Often we will not only not be interested in what the image sensor can see at a great distance, and we can use the ranging capabilities of any ranging arrangement 308 to help us ignore activity and / or presence at distances / locations outside our specific area of interest. Radar and time of flight ranging can also help to overcome an overly sensitive low power (e.g. thermal) sensor whose range exceeds the maximum depth of the specific area of interest. The range of a radar / time of flight detector is at least in part dictated by the launch power of the (RF) pulses used for ranging, and in general we may be working with specific area of interest whose depth (and breadth) is such that we don’t have to work at the ranging arrangement’s (radar’s) maximum possible launch power and this is very helpful in terms of extending battery life (when that is a relevant consideration). This possibility to trim the range of the ranging arrangement (e.g. radar) by controlling power doesn’t really exist for the image sensor or low power sensor, and although their fields of view can be adjusted using optical masks, lenses and filters these are much harder to manage in a practical setting where details of the adjustments required are likely to be unique to each particular site and mounting location.

[0062] Whereas a PIR sensor generally has a wide field of view, a Time-of-flight (TOF) sensor could optionally have a narrower field of view. This could go partway to overcoming the limitation that some TOF sensors only measure distance without direction. The field of view could be limited mechanically, by an (ultrasonic) baffle or lens or collimator, or it could be a characteristic of the transducer used in the TOF module. Reducing the field of view of the TOF sensor (where used) can go some way to reducing risk of false positives. If a PIR sensor is used it is likely to detect many motion detection events which are false positives for the device. A TOF sensor with a limited FOV can reduce the incidence of false positives, and reduce the number of times the camera needs to be powered up. {end of unedited insert}

[0063] Figure 5 shows a potential view from the video doorbell 106 of the installation of Figures 1, 2 and 4, showing pedestrians 600 on the pavement 406 of the street 404 immediately outside the premises, and also shows that pedestrians 602 on the pavement 408 on the opposite side of the street 404 are also visible. Also shown in the figure is a bus or coach 604 within which it might on occasion be possible to see the faces of the driver and passengers. Fortunately, while in the figure the pedestrian 600, 602, and the coach 604 are within the field of view of the camera of the video doorbell, that is they are within the monitored area, they are all outside the target zone (specific area of interest) of the monitored area and therefore even if the presence of the pedestrians 600 at the gateway is detected by the thermal sensor ranging information from a ranging arrangement may show that they are out of range and hence, if a ranging arrangement is provided, the processor 302 will not activate the camera of the video doorbell. The use of a ranging arrangement may, for example, enable the processor 302 to decide not to capture an image such as that of Figure 5 where the only motion / presence is in the remote public area defined by the street. It will be recognised however that only a small proportion of private premises have the luxury of such extensive grounds, with for example 8 or 10 metres or more of private grounds separating the protected premises from the nearest public walkway or street. More ubiquitous situations are represented schematically in Figure 6, in which image A represents an image from a video doorbell of premises where the protected premises are separated from the closest public space, such as a street, by less than 8 metres, for example 3 to 5 metres; image B represents an image from a video doorbell of premises where the protected premises are separated from the closest public space, such as a street, by about 3 metres; and image C represents an image from a video doorbell of premises where the protected premises open more or less directly onto a public space, such as a street, e.g. with a separation of less than about 1 metre. In the last case any image capture may be largely of occupants of public space, and even in case B it is likely that many triggered captures will include images of occupants of the public space.

[0064] It will be appreciated that one of the constraints under which image capture arrangements now operate, in most parts of the world, is a restriction based on privacy of personal data including for example image data - exemplified by the European Union’s General Data Protection Regulation (GDPR). This constraint manifests itself as restrictions on the capture and handling of images of persons. This represents a challenge for, for example, video doorbell installations that can capture images of a street or other outdoor public space, other private properties, or communal areas of multi-occupancy buildings such as condominiums, and likewise for security cameras of alarm installations that have the same kinds of outlook. Embodiments of the present invention provide a means to address this constraint by providing an image capture arrangement device which performs a method in which in response to the detection of presence within the monitored area, images of a monitored area are captured and temporarily storing the images on the device; and a timer started upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from a controller of a security monitoring system a notification in respect of the temporarily stored images; and in the event of receiving notification from the controller of the security monitoring system in respect of a security event, transmitting to the controller of the security monitoring system temporarily stored images.

[0065] Depending upon the configuration of the video doorbell (or other image capture device), the mother and child 700 in Figure 7, which shows the spacious property also shown in Figure 5 may when first detected entering the property initially be determined to be outside a defined near field and hence the processor 302 of the video doorbell may not yet consider it appropriate to activate the image sensor / camera. But as the mother and child approach the house 100 the processor may determine that they are within the defined near field zone and hence activate the camera of the video doorbell to capture an image such as that shown in Figure 7. Here, although care needs to be taken because of the presence of pedestrians 600, 602, in the street the image may be processed to hide or suppress the features of their faces while leaving visible the facial features of the mother in the visitors group 700.

[0066] One approach may be to identify the image portions corresponding to the in-range people 700 and then to define a bounding box around the relevant image portion(s) as shown as 900 in Figure 7. The processor processing the image can then retain the image detail within the bounding box and de-detail the image portion(s) not contained within a bounding box - as before, there are many ways of de-detailing but generally these involve removing relevant pixel detail, for example by unifying the pixel values, e.g. by “greying out”. But it may not be possible to adopt the approaches described with reference to Figure 7 in the situations illustrated in Figure 6, particularly in the case of 6B and 6C. For those and similar situations, the described approach of temporarily storing captured images on the image capture device and then deleting them unless the controller of the security monitoring system requests them provides a means to address the demands of the GDPR (and the like) while also providing image captures when these may be helpful in addressing a security threat or incident (such as burglary, theft or vandalism).

[0067] We therefore provide a premises security monitoring system installation that includes a controller and a plurality of sensors, operatively connected to the controller, for the detection of security events, the installation comprising a device including an image capture arrangement arranged to monitor a monitored area. The image capture arrangement device includes presence detection means to detect presence within the monitored area, and the image capture arrangement being configured to: capture images of the monitored area responsive to the detection of presence within the monitored area; temporarily store the images on the device; and start a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from the controller of the security monitoring system a notification in respect of the temporarily stored images. The controller of the security monitoring system being configured, in the event of receiving notification of a security event, to communicate with the image capture arrangement for the image capture arrangement device to transmit to the controller temporarily stored images.

[0068] In such an installation, upon expiry of the timer captured images may be deleted in the sense that the image data are made unavailable for future access, for example by one or more of the following: overwriting, removing directory information for the file, deleting an encryption key with which the data are encrypted.

[0069] In such an installation the image capture arrangement device may be in the form of a video doorbell or access device for the security monitoring system, the device being configured to respond to a physical interaction with a person by capturing and retaining on the device images of the person involved in the interaction. In such an installation the image capture arrangement device may be configured to upload to the controller of the security monitoring system images of the interaction. In such an installation the device may be configured to upload to the controller of the security monitoring system images of the interaction only in response to an instruction from the controller of the security monitoring system.

[0070] In installations according to any aspect of the invention the controller 208 of the security monitoring system may be configured to report a notified security event to a remote monitoring centre 210 and make available to the remote monitoring centre 210 images received from the image capture arrangement device.

[0071] In such an installation the controller 208 of the security monitoring system may further be configured to cause the image capture arrangement device to continue to capture and supply images, and optionally associated audio, of the monitored area. In this way the remote monitoring centre 210 may be provided with images, virtually in real time, of events taking place at the monitored premises.

[0072] The image capture arrangement device may be configured to capture images of the monitored area only in response to the detection of presence exceeding a duration of at least several seconds, optionally at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 20 or more seconds. In this way it may be possible to avoid capturing images of people who are merely passing by, but still to capture images of those loitering, “casing the joint”, or otherwise acting suspiciously.

[0073] In installations according to any aspect of the invention the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of presence within a near field zone of the monitored area, optionally the near field zone extending no more than 3 metres from the device, optionally no more than 2.5 metres from the device, optionally no more than 2 metres of the device, optionally no more than 1.8 metres of the device, optionally no more than 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, or 1 metres from the device.

[0074] The image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement within the monitored area, optionally movement towards the device. Movement, and particularly movement towards the device, may signify an increased threat of an incident and hence it may be helpful to take account of movement when trying to capture relevant images.

[0075] The image capture arrangement device is configured to capture images of the monitored area in response to the detection of movement towards a point of entry, for example windows or doors, to premises protected by the security monitoring installation. By paying attention to potential points on ingress, through which burglars or other intruders may enter, it may be possible to capture evidence of the act of entry as well as images showing the features of the villain(s) involved - and this may be particularly helpful because at this stage the villain(s) may not have their faces covered (so as not to draw attention to themselves).

[0076] The images captured by the image capture device may be video images, with or without sound, or still images.

[0077] In installations according to any aspect of the invention the timer may have a duration of no more than 30 minutes, optionally no more than 20, 19, 18, 17, 16 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or 4 minutes.

[0078] In installations according to any aspect of the invention the image capture arrangement device may be configured to reset the timer if, before expiry of the timer, presence is again detected following a period in which no presence was detected.

[0079] In installations according to any aspect of the invention image data of captured images may be held in the device in an encrypted form.

[0080] In installations according to any aspect of the invention the image capture arrangement device may be configured to encrypt image data of captured images before the data are shared between the image capture arrangement device and the controller.

[0081] In installations according to any aspect of the invention the image capture arrangement device may be configured as one or more of a video doorbell device, an access device for the security monitoring system, or a security camera of the security monitoring system.

[0082] Also provided is a method performed by an image capture arrangement device, the method comprising the steps of monitoring a monitored area, in response to the detection of presence within the monitored area, capturing images of the monitored area, temporarily storing the images on the device, and starting a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from a controller of a security monitoring system a notification in respect of the temporarily stored images. In the event of receiving notification from the controller of the security monitoring system in respect of a security event, the image capture arrangement device transmitting to the controller of the security monitoring system temporarily stored images.

[0083] In such a method, upon expiry of the timer captured images may be deleted in the sense that the image data are made unavailable for future access, for example by one or more of the following: overwriting, removing directory information for the file, deleting an encryption key with which the data are encrypted.

[0084] In a method according to any aspect of the invention the image capture arrangement device may be configured to capture images of the monitored area only in response to the detection of presence exceeding a duration of at least several seconds, optionally at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, or more seconds. In a method according to any aspect of the invention the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of presence within a near field zone of the monitored area, optionally the near field zone extending no more than 3 metres from the device, optionally no more than 2.5 metres from the device, optionally no more than 2 metres of the device, optionally no more than 1.8 metres of the device, optionally no more than 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, or 1 metres from the device.

[0085] In a method according to any aspect of the invention the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement within the monitored area, optionally movement towards the device.

[0086] In a method according to any aspect of the invention the image capture arrangement device may be configured to capture images of the monitored area in response to the detection of movement towards a point of entry to premises protected by the security monitoring installation.

[0087] In a method according to any aspect of the invention the timer may have a duration of no more than 20 minutes, optionally no more than 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or 4 minutes.

[0088] In a method according to any aspect of the invention the image capture arrangement device may be configured to reset the timer if, before expiry of the timer, presence is again detected following a period in which no presence was detected.

[0089] Also provided is an image capture arrangement device configured to perform the method of any aspect of the invention. Such an image capture arrangement device may be in the form of a video doorbell or access device for the security monitoring system, the device being configured to respond to a physical interaction with a person by capturing and retaining on the device images of the person involved in the interaction. Such an image capture arrangement device may be configured to upload to the controller of the security monitoring system images of the interaction.

[0090] Such a device may be configured to upload to the controller of the security monitoring system images of the interaction only in response to an instruction from the controller of the security monitoring system.

[0091] Range information, where used, may be determined at least partly from processing the image. For example, range may be calculated by measuring the position of a person’s feet within the image. A person’s feet are characteristics that may be recognised by an image processing algorithm. The position of a person’s feet can provide an indication of the distance between the camera and the person independently of the height the person.

[0092] The image sensing arrangement and / or the processing arrangement may be operated in a low-power mode for performing certain operations, including certain image generating and image processing operations. For example, in a low power mode, the camera may be configured to generate a monochromatic image, or a single colour channel image, e.g. R, or G or B. Additionally or alternatively, in a low power arrangement, the image processing arrangement may be configured to process monochromatic image information, or single colour channel information, e.g. R, or G or B. Such a technique may provide of simplified processing compared to processing full-colour image information, and facilitate lower power consumption.

Claims

Claims1. A device for a premises security monitoring system installation, the device including an image capture arrangement arranged to monitor a monitored area, the image capture arrangement device including presence detection means to detect presence within the monitored area, and the image capture arrangement being configured to: i) capture images of the monitored area responsive to the detection of presence within the monitored area; ii) temporarily store the images on the device; and iii) start a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from the controller of the security monitoring system a notification.

2. A device as claimed in claim 1, wherein upon expiry of the timer captured images are deleted in the sense that the image data are made unavailable for future access, for example by one or more of the following: overwriting, removing directory information for the file, deleting an encryption key with which the data are encrypted.

3. A device as claimed in any one of the preceding claims configured to capture images of the monitored area only in response to the detection of presence exceeding a duration of at least several seconds, optionally at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or more seconds.

4. A device as claimed in claim 1 or claim 2, configured to capture images of the monitored area in response to the detection of presence within a near field zone of the monitored area, optionally the near field zone extending no more than 3 metres from the device, optionally no more than 2.5 metres from the device, optionally no more than 2 metres of the device, optionally no more than 1.8 metres of the device, optionally no more than 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, or 1 metres from the device.

5. A device as claimed in claim 1 or claim 2, configured to capture images of the monitored area in response to the detection of movement within the monitored area, optionally movement towards the device.

6. A device as claimed in claim 5, configured to capture images of the monitored area in response to the detection of movement towards a point of entry to premises protected by the security monitoring installation.

7. A device as claimed in any one of the preceding claims, wherein the images are video images with or without sound.

8. A device as claimed in any one of claims 1 to 6, wherein the images are still images.

9. A device as claimed in any one of the preceding claims, wherein the timer has a duration of no more than 20 minutes, optionally no more than 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or 4 minutes.

10. A device as claimed in any one of the preceding claims, configured to reset the timer if, before expiry of the timer, presence is again detected following a period in which no presence was detected.

11. A device as claimed in any one of the preceding claims, wherein image data of captured images are held in the device in an encrypted form.

12. A device as claimed in any one of the preceding claims, configured to encrypt image data of captured images before the data are shared between the image capture arrangement device and the controller.

13. A device as claimed in any one of the preceding claims, configured as one or more of a video doorbell device, an access device for the security monitoring system, or a security camera of the security monitoring system.

14. A device as claimed in claim 13, in the form of a video doorbell or access device for the security monitoring system, the device being configured to respond to a physical interaction with a person by capturing and retaining on the device images of the person involved in the interaction.

15. A device as claimed in claim 14, configured to upload to the controller of the security monitoring system images of the interaction.

16. A device as claimed in claim 15, configured to upload to the controller of the security monitoring system images of the interaction only in response to an instruction from the controller of the security monitoring system.

17. A premises security monitoring system installation including a controller and a plurality of sensors, operatively connected to the controller, for the detection of security events, the installation comprising a device as claimed in any one of the preceding claims, the controller of the security monitoring system being configured, in the event of receiving notification of a security event, to communicate with the device for the device to transmit to the controller temporarily stored images18. An installation as claimed in claim 17, wherein the controller of the security monitoring system is configured to: report a notified security event to a remote monitoring centre; and make available to the remote monitoring centre images received from the image capture arrangement device.

19. An installation as claimed in claim 17 or 18, wherein the controller of the security monitoring system is further configured to cause the device to continue to capture and supply images of the monitored area.

20. A method performed by an image capture arrangement device, the method comprising the steps of: i) monitoring a monitored area; ii) in response to the detection of presence within the monitored area, capturing images of the monitored area; iii) temporarily storing the images on the device; and iv) starting a timer upon expiry of which the temporarily stored images are deleted unless before expiry of the timer the image capture arrangement device has received from a controller of a security monitoring system a notification in respect of the temporarily stored images.

21. The method of claim 20, further comprising, in the event of receiving notification from the controller of the security monitoring system in respect of a security event, transmitting to the controller of the security monitoring system temporarily stored images.

22. The method as claimed in claim 20 or 21, wherein upon expiry of the timer captured images are deleted in the sense that the image data are made unavailable for future access, for example by one or more of the following: overwriting, removing directory information for the file, deleting an encryption key with which the data are encrypted.

23. The method as claimed in any one of claims 20 to 22, wherein the image capture arrangement device is configured to capture images of the monitored area only in response to the detection of presence exceeding a duration of at least several seconds, optionally at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or more seconds.

24. The method as claimed in any one of claims 20 to 23, wherein the image capture arrangement device is configured to capture images of the monitored area in response to the detection of presence within a near field zone of the monitored area, optionally the near field zone extending no more than 3 metres from the device, optionally no more than 2.5 metres from the device, optionally no more than 2 metres of the device, optionally no more than 1.8 metres of the device, optionally no more than 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, or 1 metres from the device.

25. The method as claimed in any one of claims 20 to 22, wherein the image capture arrangement device is configured to capture images of the monitored area in response to the detection of movement within the monitored area, optionally movement towards the device.

26. The method as claimed in any one of claims 20 to 22, wherein the image capture arrangement device is configured to capture images of the monitored area in response to the detection of movement towards a point of entry to premises protected by the security monitoring installation.

27. The method as claimed in any one of claims 20 to 26, wherein the timer has a duration of no more than 20 minutes, optionally no more than 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, or 4 minutes.

28. A method as claimed in any one of claims 20 to 27, wherein the image capture arrangement device is configured to reset the timer if, before expiry of the timer, presence is again detected following a period in which no presence was detected.

29. An image capture arrangement device configured to perform the method of any one of claims 20 to 28.

30. An image capture arrangement device as claimed in claim 29, in the form of a video doorbell or access device for the security monitoring system, the device being configured to respond to a physical interaction with a person by capturing and retaining on the device images of the person involved in the interaction.

31. An image capture arrangement device as claimed in claim 30, wherein the device is further configured to upload to the controller of the security monitoring system images of the interaction.

32. An image capture arrangement device as claimed in claim 31, wherein the device is configured to upload to the controller of the security monitoring system images of the interaction only in response to an instruction from the controller of the security monitoring system.

Images