GB2416084A

GB2416084A - Mobile surveillance system

Info

Publication number: GB2416084A
Application number: GB0415499A
Authority: GB
Inventors: Mark Stratford
Original assignee: SECOND SIGHT SURVEILLANCE Ltd
Current assignee: SECOND SIGHT SURVEILLANCE Ltd
Priority date: 2004-07-10
Filing date: 2004-07-10
Publication date: 2006-01-11
Anticipated expiration: 2024-07-10
Also published as: GB2416084B; GB0415499D0

Abstract

A mobile surveillance system comprises: a camera system 1 having a camera 3, preferably having a removable lens 15, and an audio system 5 to capture images and sound; a communications device 7 for receiving, and preferably transmitting, communications from/to a control centre and/or other devices; and means 9, preferably a wirelessly remote video recorder, to compile a synchronised record of visual and audio events. A light source 33 may be provided, preferably infrared, illuminating subjects recorded by the, preferably infrared sensitive, camera. The camera system casing 17 may have a front section 19, housing the camera 3, pivotally attached to a rear section 21 which is attachable to an object. Preferably, the audio system 5 has attenuation means comprising a first input receiving sound from a target, and background noise, and a second input receiving background noise, which is inverted then mixed with sound from the first input providing noise reduction. Preferably a switch is provided, which once activated, the user cannot deactivate the system, or alternatively only the camera may be switched on or off.

Description

24 1 6084 Mobile Surveillance System The present invention relates to a

surveillance system and to a camera system for the surveillance system.

For law enforcement agencies there is a need to produce accurate records of events, for example when making an arrest, for evidential purposes to substantiate the arresting of ficer's version of events. Currently, this is done after the event with each officer involved in the incident producing a written account of higher actions. This may be produced several hours after the incident took place and crucial details may be forgotten in the intervening period.

This can hamper the subsequent prosecution of the criminal and may prevent a conviction 0 from being made.

Occasionally, law enforcement officers may find themselves in situations where they are the only witness to criminal activities or accidents, and therefore there would be nobody else available to corroborate the of ficer's version of events. The strength of a prosecution may be reliant upon the testimony of single individual, which is undesirable.

A similar situation arises when there are witnesses available, but the witnesses are hostile towards the law enforcer and are prepared to lie to protect the arrested person. In this situation it is the officer's word against the testimony of a number of individuals. Furthermore, accusations may be made against the officer, for example alleging that he/she acted inappropriately in some way during the incident, such as assaulting, verbally abusing or intimidating the detainee. If there is no impartial witness available who can corroborate the officer's version of events, the officer may be unjustly punished. Similarly, there may be other witnesses to the event who are unwilling to testify against a criminal because of intimidation or the fear of intimidation. The witnesses may also be intimidated by the prospect of being a witness in court or have legitimate reasons for not involving themselves with the law 2s enforcement agency. In either case, there may be a lack of evidence to convict the criminal.

The need for reliable evidence increases with the gravity of the situation. In the United Kingdom there are specially trained anned response units that deal with hostage situations, terrorist incidents and other incidents where fireanns are used, for example armed robberies.

It may be necessary for officers of such units to fire their weapons at armed persons to incapacitate them. In such situations it is crucial that there is an accurate record of the events leading up to the discharge of the weapon to ensure that the officers acted properly and only fired at the target in accordance with the instructions provided by the commanding officer.

Law enforcement of ricers are not the only people who are subject to allegations of improper conduct in the line of discharging their duty. Other persons include security guards in public areas, for example in shopping centres, exhibition halls and hotels, marshals at an event such as protest marches, event management in the sports and entertainment industries and nightclub doormen. The last group of individuals are particularly prone to allegations of improper 0 conduct because there is often violence at nightclubs as customers may drink to excess or take drugs, leading to aggressive behaviour which the doonnen have to deal with. Other government agencies who may have similar problems are council housing inspectors, customs of ficials and the military for use in tactical teams, live theatre or during training operations.

Accordingly, there is a need for a means of recording events in real time that law enforcers and similar persons can carry with them when on duty.

According to one aspect of the present invention there is provided a mobile surveillance system including a camera system having a camera and an audio system for recording visual images and sound, a communications device for receiving communications from a control centre and/or other communications devices, and recording means for synchronously recording visual images captured by the camera, sound captured by the audio system and communications received by the communications device to produce a record of events.

Advantageously the record of event can be used as evidence of what transpired during a particular incident, including the orders or information the user was supplied with via the communications device. If a number of users, such as a group of law enforcement of ricers use the tool, all the records of event can be assessed. The invention can also be used as a training tool to analyse the effectiveness of individuals using the system and teams of individuals.

Advantageously the camera system and communications device are arranged to be carried by a user. Optionally, the recording means may also be arranged to be carried by the user.

Preferably the communications device is arranged to send communications and the recording means is arranged to synchronouslyrecord communications sent by the device with the sound and visual images. For example, the communications device is arranged to receive audio communications and preferably is a two way radio, wherein the user ofthe surveillance system is able to verbally communicate with a person at the control centre and / or with other persons having similar communications devices.

Advantageously the surveillance system includes a light source for illuminating subjects to be recorded by the camera. Preferably the light source is a light emitting diode.

Advantageously the camera can be an infrared sensitive camera and the light emitting diode can operate in the infrared spectrum. This enables the camera to record images in total darkness. Preferably the infrared sensitive camera is a conventional monochrome camera.

lo Preferably the camera includes a removable lens. The lens can be removed and replaced with a different lens to accommodate different filming requirements, for example a wide angled lens can be used or a zoom lens.

Preferably the camera system is housed in a casing having first and second sections that are pivotally attached to each other. The camera lens can be housed in the first part of the casing and the second part of the casing can include a means for fixing the casing to an object. This allows a user of the surveillance system to mount the camera on an object such as a helmet, or pole, and adjust the direction in which the camera lens points relative to second section of the casing and hence the object on which the casing is mounted. Preferably the means for fixing the casing to an object includes a formation arranged to engage a complementary formation mounted on the object, for example the casing can include a female formation and the object a male formation, and vice versa.

Advantageously the audio system includes anoise attenuation means forreducingbackground noise recorded by the system. Preferably the noise attenuation means includes a first input for receiving sound from a target and background noise and a second input arranged to receive background noise. Advantageously the noise attenuation means is arranged to invert the background noise wavefonn received at the second input and to mix it with the sound received by the first input to reduce the background noise. The audio system includes a microphone for detecting the sound output of the noise attenuation means.

Preferably the noise attenuation means includes a first aperture in the casing arranged to receive sound from the subject being filmed and a second aperture arranged to receive background noise. ThefirstaperLureis substantially axially aligned with the axis ofthe camera and the second aperture is arranged at between approximately 85 to 180 degrees to the first aperture. Preferably the second aperture is arranged at between 85 to 130 degrees to the first aperture, and more preferably at approximately 90 degrees. The second aperture has a smaller s diameter than the first aperture. Preferably the second aperture has a diameter that is approximately one third of the diameter of the first aperture. The noise attenuation means includes a chamber for mixing the sound received through the first aperture with sound received through the second aperture.

Preferably the recording means is a video recorder. The video recorder may be of any suitable lo kind and can synchronously record the sound and images received onto any suitable storage means, for example on to tape, digital or analogue, a hard disk drive or memory chips. In one embodiment the recording means can be located in the casing.

Advantageously the camera system can include a switch means arranged such that once activated at least one of the camera and audio system cannot be deactivated by the user.

Preferably the switch means is arranged such that the camera can be switched on and off by a user but the audio system cannot be disabled.

In one embodiment the recording means is located remotely from the user and sound and visual images recorded by the camera system and received by the communications device are transmitted wirelessly to the recording means.

According to another aspect of the present invention there is provided a camera system for recording visual images and sound including a camera and an audio system characterized in that the audio system includes a means for reducing background noise.

Preferably the noise attenuation means includes a first input for receiving sound from a target and background noise and a second input arranged to receive background noise.

Advantageously the noise attenuation means is arranged to invert the background noise wavefonn received at the second input and to mix it with the sound received by the first input to reduce the background noise. The audio system includes a microphone for detecting the sound output of the noise attenuation means.

Preferably the noise attenuation means includes a first aperture in the casing arranged to receive sound from the subject being filmed and a second aperture arranged to receive background noise. The first aperture is substantially axially aligned with the axis ofthe camera and the second aperture is arranged at between approximately 85 to 180 degrees to the first aperture. Preferably the second aperture is arranged at between 85 to 130 degrees to the first aperture, and more preferably at approximately 90 degrees. The second aperture has a smaller diameter than the first aperture. Preferably the second aperture has a diameter that is approximately one third of the diameter of the first aperture. The noise attenuation means includes a chamber for mixing the sound received through the first aperture with sound received through the second aperture.

According to another aspect of the present invention there is provided a camera for recording lo visual images including a light emitting diode for illuminating subjects to be recorded.

An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which like references indicate equivalent features, wherein: Figure 1 is a diagrammatic representation of a mobile surveillance system in accordance with the invention; Figure 2 is a perspective view of a casing for housing a camera and an audio system; Figures 3a to 3d illustrate the effectiveness of white light illumination from a 1450 mod LED with 40 spread; Figure 4 is a perspective view of one part of the casing of Figure 2; and Figure 5 illustrates the principle of reducing background noise captured by the audio system; Figure 1 illustrates amobile surveillance system in accordance with the present invention. The surveillance system includes a camera system 1 having a camera 3 and audio system 5, a two way radio 7, a video recorder 9 and a control device 11.

The camera 3 is a video camera for recording real time visual images which are stored using the video recorder 9. The camera is a colour digital video camera such as WATEC 240 and has a conventional wire output connection 13 to the video recorder 9. The camera is typically powered by electric cells such as rechargeable batteries (not shown).

The camera 3 includes a lens 15 that is arranged to be disconnected from the main body of the camera such that alternative lenses can be fitted to the camera to account for different visual recording requirements.

The camera 3 is mounted in a casing 17. The casing has a front part 19 that houses the camera lens]5 and sensor (not shown), and a rear part 21 that houses the audio system 5 and electronic circuitry associated with the camera and audio system. The audio system 5 includes a microphone 23 for recording sounds and a noise attenuation device 25 for reducing the effect of background noise 27 on the quality of sound recorded by the microphone. The casing 17 is made from a plastics material such as a glass reinforced nylon. The front part 19 of the casing comprises a tubular member that is substantially barrel shaped. The barrel] 9 is l o pivotally attached to the rear past 21 by a pivot pin 29. A moulding 31 made from a flexible material such as rubber covers the connection between the barrel] 9 and the rear part 21 ofthe casing. The camera lens 15 is housed within the barrel 19 towards the opposite end from that which is attached to the rear part 21 of the casing. The lens 15 can be removed from the camera by disconnecting the barrel 19 from the rear part 21 of the casing and replacing it with another barrel housing a different lens. The whole camera can be replaced in a similar fashion as improved cameras become available.

The casing 15 includes a female connector 32 for attachment to a complementary made connector (not shown), for example located on a helmet, a head band, a pole or a harness for a human or animal. The female connector 32 comprises a dovetailed slot. The pole may include a lockable swive] ball joint to allow pan and tilt movement. This will enable the camera to see into inaccessible places, for example during searches. The various components of the system can be carried by the user, for example in a vest, coat or belt.

Located beneath the lens is a white light LED 33 for illuminating subjects to be recorded by the camera. The I ED has a light intensity rating of 1450 milk candles, with a 40 spread. The illumination provided by the LED 33 is sufficient to illuminate a subject at a distance of around two metros at night (see Figures 3a to 3d). LEDs have lower power consumption than conventional bulbs and are more reliable in that the time to failure is substantially longer than a that for a conventional bulb.

A second LED 35 is used to indicate the operational status of the camera. Preferably the surveillance system Will] be arranged such that it cannot be switched offonce activated. This wild prevent a user from deactivating the surveillance system, for example when on patrol. In this instance, it is preferable that the system includes a switch that can deactivate the camera 3 but not the audio system S so that sound will always be recorded but visual images are optional. The second LED 35 will indicate the status of the system.

Therearpart21 ofthe casing comprises first and second moulded halves 21a, 21b that connect together by a snap fit sealing arrangement. The two halves 21a,21b are secured together by two screws (not shown). The first and second halves 21 a,21b are substantially identical but are mirror images of each other.

The rear part 21 of the casing will now be described with reference to Figures 2 and 4. The rear pert 21 includes a neck portion 37 arranged to receive the barrel 19. The neck portion 39 lo includes formations 39 defining a through hole 41 arranged to receive the pivot pin 29 on which the barrel pivots relative to the rear part 21. When the barrel 19 is pivotally attached to the rear part 21 ofthe casing the barrel 19 is able to pivot relative to the rear part 21 ofthe casing between discrete positions. The barrel can be pivoted from a first position 43 which is substantially horizontal to a second position 45 that is inclined upwards by 11 relative to rear part of the casing. The barrel can be pivoted downwards from the first position to a third position 47 that is inclined downwards by 11 , to a fourth position 49 that is inclined downwards by 22 , and to a fifth position 51 that is inclined downwards by 33 . This allows the user of the surveillance system to adjust the direction in which the lens 15 is pointing to focus on different subject matter. For example, if the camera 3 is mounted on a user's helmet, it allows the user to record something towards ground level, such as an injured party lying on the ground, whilst maintaining his / her head in an upright position, thus allowing the user to remain alert to other events whilst filming the injured party on the ground.

The rear part 21 of the casing has an arcuate lower peripheral wall 53 that extends downwards from the neck portion 37. A first aperture 55 is Conned in the arcuate wall that is arranged to allow sound to enter the rear part 21 of the casing. The first aperture 55 is aligned with the longitudinal axis of the barrel to capture sounds originating from the subjects being filmed by the camera 3. The first aperture 55 opens into a first chamber 57 that is substantially cuboid and is defined by the side walls ofthe casing 59 and by first and second internal walls 61,63 that are integrally formed with the casing. The microphone 23 is located in a recess donned between the first wall 61 and a third wall 65 adjacent the first aperture. The microphone 23 is directed towards the first aperture 55 such that sound entering the casing is picked up by the nicrophone.

A second aperture 67 is formed in the lower peripheral wall of the rear casing that is arranged at approximately 90 to the first aperture 55. The second aperture 67 has a diameter one third of the size of the first aperture. Sound entering the second aperture 67 is predominately s background noise. The second aperture 67 opens into a second chamber 69. The second chamber 69 is defined by part of the lower peripheral wall 53 of the casing, the sides of the casing 59, the third internal wall 65 and a fourth internal 71 which is inclined to the third internal wall 65. The second chamber 69 comprises a smaller volume than the first chamber 57.

lo A notch 73 Donned in the third internal wall 65 towards the end adjacent the first aperture allows sound to propagate from the second chamber 69 into the first chamber 57.

Although the first aperture 53 is directed towards the subjects being filmed and is intended to capture sounds originating from those subjects 28, any sound waves entering the aperture will also contain components of background noise from other sound sources in the vicinity ofthe user. For example, if the user is a police of ricer and the surveillance system is being used at the scene of an incident, there may be background noise issuing from sirens, alarms, music, shouting from bystanders, etc. The arrangement of the second aperture 67 and the second chamber is such that the inbound background noise is inverted. When the inverted sound waves are mixed in the first chamber 57 with the inbound sound entering through the first aperture 55 the result is reduction of the background noise. The microphone 23 detects the sound waves having reduced background noise and thereby captures better quality sound issuing from the subjects being filmed in front ofthe camera. This is shown diagrammatically in Figure 5. In tests the background noise has been found to be attenuated by around 3dB.

The audio output 13 from the audio system 5 is connected to the video recorder 9 such that the 2s recorder 9 can store the sounds detected by the microphone 23.

The two way radio 7 can be used to send and receive verbal messages so that the user can receive instructions / communications from a control centre or from other persons having similar radios, for example other members of a police special operations team, regular pahrol officers, doonnen in night clubs, security guards in shopping centres, industrial installations, or events such as pop concerts, military personnel or stewards marshalling public marches.

The radio 7 has an audio output 77 that is connected to the video recorder 9 such that the video recorder 9 can record communications between the user and the control centre and / or other persons having similar radios. The audio output 77 from the radio is fed from the video recorder 9 to an output connection for an Otto earpiece located in the camera casing. The user s can use the ear piece to hear communications received by the radio 7.

A preferred video recorder 9 is a Sony DV 8 tape recorder with integral LCD monitor.

Alternatively a video recorder 9 that digitises video data and stores it on a hard disk drive can be used. A 20Gb hard disk can currently store 12 hours of real-time video, including both visual and audio data. It is anticipated that in the future these devices will have larger storage 0 capacity. Digital video recorders are typically smaller and lighter than tape recorders and are therefore easier for a user to carry, but they are currently more expensive.

The video recorder 9 is arranged to synchronously record visual images captured by the camera 3, sound captured by the audio system 5 and communications between the user and the control centre and / or other persons having similar radios to produce a record of an event.

That is, the record of an event from the video recorder 9 can be analysed to assess the actions of people recorded by the camera system 1, the actions of the user including any verbal communication between the user and the subjects recorded by the camera system 1, and also the instructions / information provided to the user by the control centre or other persons communicating with the user via the radio. Since the visual, audio and radio communications are synchronised it is then possible to make judgements about the behaviour of the subjects filmed and the actions of the user of the surveillance system. Thus the record of event has significant evidential value for police forces that want to prosecute the subjects of the video.

The record of event may also protect police officers when allegations of inappropriate behaviour are made against them since their actions will also be recorded by the system. The record of event can also be used to record training exercises. The record can then be reviewed to analyse how to improve operational effectiveness.

The control device 11 includes a rocker switch 79 for activating / deactivating the video recorder 9. The switch includes an LED to indicate the operational status of the video recorder 9. The control device can be connected to the video recorder 9 by a cable 81 or can use a wireless connection such as an infrared control system. The control device can be arranged to clip on to a lapel.

ln the case of a police officer, a user nounts the camera system on a helmet pointing in substantially the same direction as the user is viewing. The video recorder 9 and radio 7 are located in a vest, are attached to a belt or harness or are located m pockets in an overcoat.

There are wires 13,77 connecting the r adio 7 and camera system I to the video recorder 9. The user may optionally use an earpiece that can be connected to the camera system I. When the of ricer is ready to start his/her patrol the surveillance system is activated and sound and visual images are recorded on the video recorder 9. If during the patrol the officer is contacted by another of ricer having a similar r adio 7 or by a control centre the communication between them is recorded by the video recorder 9. Since the communications, sound and visual 0 images are recorded synchronously it will be known when the officer received the communication and what action was taken in response to the communication. For example, if the officer is am1ed and, at the scene of an incident where a hostage is being held by an anned assailant, the officer may receive an instruction to, Shoot the assailant should there be a serious threat to the safety of the hostage. The camera will record what the officer can see and hear at the scene, the order to shoot and the subsequent action of the of ricer. The record of eventproduced canboused curing subsequent legal proceedings to help convictthchostage taker.

If the patrol of ricer should arrive at a scene where in his/her judgement it is inappropriate to record visual images the office has the option of switching offthe camera 3. As a safeguard the audio system 5 cannot be disabled and therefore a sound record and the communications sent and received by the radio 7 will still be recorded by the video recorder 9.

It will be appreciated that alterations can be made to the embodiment described above without departing frown the scope of the present invention For example, the camera 3 can be colour ormonochrome, analogue or digital. If an infrared sensitive camera is used in conjunction with :5 an infrared I ED the camera is able to record images in total darkness. For example, some conventional monochrome cameras are infrared sensitive.

Instead of using a tape or hard disk storage device data can be recorded synchronously using other storage means such as memory chips, DVD, memory cards or any other suitable analogue or digital storage medium. The video recorder can be Incorporated into the camera casing. It is envisaged that as technology In data / memory chips develops the video and audio data could be stored in C}lipS located In the camera casing. Alternatively, the video storage means can be located remotely from the user and the system will include suitable telemetry such as "Blue Tooth" for sending data to be recorded to the video storage means. As Public Wide Area Networks are developed the communications range between the user and the remote video storage means can be increased.

Communications devices other than radios can be used to send messages to a user of the system, for example telephones, and text messaging services. The communications received and sent by such devices can also be synchronously recorded by the video recorder 9.

The surveillance system is preferably arranged so that it is visible and it would be obvious to a subject being filmed that a user is operating the system. Alternatively, the system can be lo arranged to be covert if necessary. \

Claims

Claims 1. A mobile surveillance system including a camera system having a

camera and an audio system for recording visual nnages and sound, a communications device for receiving communications from a control centre and/or other communications devices, and recording means for synchronously recording visual images captured by the camera, sound captured by the audio system and communications received by the communications device to produce a record of events.
2. A mobile surveillance system according to claim 1, wherein the communications device is arranged to send communications and the recording means is 0 arranged to synclonously record communications sent by the device with the sound and visual images.
3. A mobile surveillance system according to claim I or 2, including a light source for illuminating subjects to be recorded by the camera.
4. A mobile surN eillance system according to claim 3, wherein the camela is an infrared IS sensitive camera and the light emitting diode operates in the infrared spectrum.
5. A mobile surveillance system according to any one of the preceding claims, wherein the camera includes a removable lens.
6. A mobile surveillance system according to any one of the preceding claims, including a casing for housing the camera system.
7. A mobile surveillance system according to claim 6, wherein the casing includes first and second sections that are pivotally attached to each other.
8. A mobile surveillance system according to claim 7, wherein the camera lens is housed in the first part of the casing and the second pan' of the casing includes a means for fixing the casing to an object.

2j
9. A mobile surveillance system according to any one of the preceding claims, wherein the audio system includes a noise attenuation means for reducing background noise r ecorded by the system.
10. A mobile sueil]ance system according to claim 9, wherein the noise attenuation means includes a first input for receiving sound from a target and background noise and a

second input arranged to receive background noise.
11. A mobile surveillance system according to claim 10, wherein the noise attenuation means is arranged to invert the background noise waveform received at the second input.

s
12. A mobile surveillance system according to claim I I, wherein the inverted background noise waveform is mixed with the sound received by the first input to reduce the background noise.
13. A mobile surveillance system according to any one of claims 9 to 12, wherein the audio system includes a microphone for detecting the sound output of the noise attenuation lo means.
14. A mobile surveillance system according to any one of the preceding claims, wherein the recording means is a video recorder.
15. A mobile surveillance system according to any one of the preceding claims, wherein the camera system includes a switch means arranged such that once activated at least one of the camera and audio system cannot be deactivated by the user.
16. A mobile surveillance system according to claim 15, wherein the switch means is arranged such that the camera can be switched on and off by a user but the audio system cannot be disabled.
17. A mobile surveillance system according to any one of the preceding claims, wherein the recording means is located remotely from the user and sound and visual images recorded by the camera system and received by the communications device are transmitted wirelessly to the recording means.
18. A camera system for recording visual images and sound including a camera and an audio system characterised in that the audio system includes a means for reducing background 2s noise.
19. A camera for recording visual images including a light emitting diode for illuminating subjects to be recorded.
20. A mobile surveillance system substantially as described herein with reference to and as illustrated by the accompanying drawings.
21. A camera system substantially as described herein with reference to and as illustrated by the accompanying drawings.
22. A camera substantially as described herein with reference to and as illustrated by the accompanying drawings.