U.S. patent application number 16/866572 was filed with the patent office on 2020-08-20 for cross verification of data captured by a consumer electronic device.
This patent application is currently assigned to SERELAY LIMITED. The applicant listed for this patent is SERELAY LIMITED. Invention is credited to Roy AZOULAY.
Application Number | 20200265035 16/866572 |
Document ID | 20200265035 / US20200265035 |
Family ID | 1000004811295 |
Filed Date | 2020-08-20 |
Patent Application | download [pdf] |
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United States Patent
Application |
20200265035 |
Kind Code |
A1 |
AZOULAY; Roy |
August 20, 2020 |
CROSS VERIFICATION OF DATA CAPTURED BY A CONSUMER ELECTRONIC
DEVICE
Abstract
A system for cross verification of data captured by a consumer
electronic device is disclosed. Primary data, for example, a
photograph, is captured by a mobile capture device, and metadata
including the time and location of the capture is associated with
the primary data. Environmental data, for example, pressure,
temperature, visible WiFi networks, visible cell towers, is also
measure by the mobile capture device. Other capture devices are
identified in the vicinity and those other devices also measure
environmental data. The measurements of environmental data can then
be compared in order to calculate a confidence level in the
position metadata associated with the primary data.
Inventors: |
AZOULAY; Roy; (Oxford,
GB) |
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Applicant: |
Name |
City |
State |
Country |
Type |
SERELAY LIMITED |
London |
|
GB |
|
|
Assignee: |
SERELAY LIMITED
|
Family ID: |
1000004811295 |
Appl. No.: |
16/866572 |
Filed: |
May 5, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15863419 |
Jan 5, 2018 |
10678780 |
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16866572 |
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62442825 |
Jan 5, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 12/00504 20190101;
H04W 4/02 20130101; G06F 16/907 20190101; G06F 16/2365 20190101;
H04W 12/00502 20190101; G01C 1/00 20130101; H04W 12/1004 20190101;
H04W 12/00503 20190101; H04W 12/1006 20190101 |
International
Class: |
G06F 16/23 20060101
G06F016/23; H04W 12/10 20060101 H04W012/10; G01C 1/00 20060101
G01C001/00; G06F 16/907 20060101 G06F016/907 |
Claims
1. A system for attributing a confidence level to time and location
metadata associated with primary data, the system including a
plurality of mobile capture devices and a mobile data communication
network allowing data transfer between the mobile capture devices,
each mobile capture device including at least one sensor for
capturing primary data, and being adapted to provide metadata
specifying at least the time and location relating to captured
primary data, and each mobile capture device further including at
least one further sensor for measuring at least one environmental
parameter, each mobile capture device being adapted to carry out
the steps of: capturing primary data using the at least one sensor;
associating metadata with the primary data, the metadata specifying
at least the time and location of the capture; and measuring and
storing at least one environmental parameter at the time and
location of the capture, and associating the measured environmental
parameter with the primary data, in response to a trigger, and each
mobile capture device being adapted to carry out the steps of:
measuring and storing at least one environmental parameter; and
transmitting the measured environmental parameter on the
communication network, in response to a remote command, and the
system including at least one device connected to the data
communication network and being adapted to: in response to a
capture of primary data being made by a mobile capture device
forming part of the system, carry out the steps of: identifying
other mobile capture devices in a similar location at a similar
time to the capture device making the primary data capture;
requesting and receiving environmental data from other mobile
capture devices identified; comparing environmental data received
from other mobile capture devices with the environmental data
measured by the device capturing the primary data, and assigning a
confidence level to the time and location metadata associated with
the primary data based on the comparison.
2. A system as claimed in claim 1, wherein the at least one sensor
for measuring the at least one environmental parameter includes at
least one of a thermometer, a hydrometer, a pressure sensor, and/or
a light level sensor.
3. A system as claimed in claim 1, wherein the at least one sensor
for measuring the at least one environmental parameter includes at
least one of a WiFi transceiver for detecting visible WiFi networks
and a mobile telecommunications transceiver for detecting visible
cell towers.
4. A system as claimed in claim 1, wherein at least one device of
the plurality of mobile capture devices is a server, and wherein
the server identifies other nearby devices and makes
comparisons.
5. A system as claimed in claim 1, wherein at least one device of
the plurality of mobile capture devices is a mobile telephone
comprising a processor and a computer program for execution on the
processor.
6. A system as claimed in claim 1, wherein in which the confidence
level comprises a binary "verified" or "unverified" value.
7. A system as claimed in claim 1, wherein the binary value is
calculated by: .delta. x .delta. p < Max ##EQU00007## where
.delta.x is the difference in an environmental parameter measured
by two of the mobile capture devices, and .delta.p is the
difference in the position of the two devices, and Max is a
threshold, and where a "verified" value is returned if .delta. x
.delta. p ##EQU00008## is less than Max, otherwise an "unverified"
value is returned.
8. A system as claimed in claim 1, wherein a multi-level confidence
value is calculated by: .delta. x .delta. p ##EQU00009## where
.delta.x is the difference in an environmental parameter measured
by two of the mobile capture devices, and .delta.p is the
difference in the position of the two devices, and a low value of
the ratio .delta. x .delta. p ##EQU00010## indicates a high
confidence, and vice versa.
9. A system as claimed in claim 1, wherein a maximum difference in
position .delta.p which determines a device in the plurality of
mobile capture devices to be in the similar location to the other
mobile capture devices is variable according to a density of mobile
capture devices in a relevant area.
10. A system as claimed in claim 1, wherein environmental data for
a particular position is compared to a third party data source.
11. A system as claimed in claim 11, wherein visible WiFi networks
and/or visible cell towers are compared to the third party data
source.
12. A system as claimed in claim 10, wherein a position is compared
to the third party data source, and wherein the position comprises
elevation.
13. A system as claimed in claim 12, wherein the elevation is
compared to an estimated elevation determined from a pressure
sensor.
14. A system as claimed in claim 13, wherein the estimated
elevation is determined according to: h = 2 7 3 . 1 5 + T 0 0 . 0 0
6 5 ( 1 - ( P P 0 ) 1 5.255 ) ##EQU00011##
15. A system for collecting environmental data, the system
comprising at least one mobile capture device, wherein the at least
one mobile capture device carries out the steps of: capturing
primary data; associating metadata with the primary data, measuring
environmental data; associating the environmental data with the
metadata; storing the environmental data and the metadata;
utilizing the metadata to identify other mobile capture devices
nearby; accessing the other mobile capture devices; using the other
mobile capture devices to collect additional environmental data;
and verifying the environmental data by comparing the environmental
data with the additional environmental data.
16. The system for collecting environmental data of claim 15,
wherein the other mobile capture devices are triggered by the at
least one mobile capture device.
17. The system for collecting environmental data of claim 16,
wherein the triggering comprises a timed, pre-set trigger.
18. A method for measuring an environmental parameter, the method
comprising: capturing primary data using a capture device;
associating metadata with the primary data; measuring an
environmental parameter using the capture device; transmitting a
message to a server, wherein the message comprises the capture
device's physical location; using the metadata to identify other
capture devices near the capture device; and utilizing the other
capture devices to cross-verify the environmental parameter
measured by the capture device.
19. The method for measuring an environmental parameter of claim
18, wherein the metadata originates from the capture device.
20. The method for measuring an environmental parameter of claim
18, wherein the cross-verification further comprises: verifying
accuracy of the environmental parameter measured by the capture
device.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 15/863,419, filed Jan. 5, 2018, which claims priority to
Application No. 62/442,825, filed Jan. 5, 2017, each of which is
incorporated by reference in their respective entireties.
FIELD OF THE INVENTION
[0002] The present invention relates to a system and method for
verifying the accuracy of metadata attached to primary data
captured by a capture device. For example, primary data could be a
photograph, sound recording or video recording captured by a
consumer electronic device such as a mobile telephone. The metadata
may relate to the time and/or location of the capture.
BACKGROUND TO THE INVENTION
[0003] It is now common for modern mobile telephones to include a
camera for capturing stills and video, and a microphone for
capturing sound recordings, either as a sound channel to a video
recording or a separate sound recording.
[0004] Known devices, as well as recording primary data (e.g. a
photograph or a video), also record metadata relating to the
capture. For example, when capturing a photograph, many devices
will store the current time and date, and coordinates of the
physical location of the device when the photograph was
captured.
[0005] In most cases, this metadata is a convenient feature which
is useful to a consumer so that he can view and share his
photographs (for example) based on where and when they were taken,
without the need to make notes and organise the captured pictures
manually. However, in some cases verifying that the time and place
attached to a particular photograph is accurate may be
critical.
[0006] News organisations often receive submitted photographs and
videos from members of the public, but these organisations have to
be careful to verify the authenticity of what they are being
presented with--in particular that the photograph (for example)
really was taken at the time and place claimed. In the past, even
reputable news organisations have fallen victim to falsified
submitted photographs and published them as genuine.
[0007] There are generally no safeguards against false attribution
of time and place to a photograph on known devices. Even if a
mechanism exists to ensure that the current GPS location of the
device is stored with the photograph, and even if there is a
mechanism to prevent later tampering with that location metadata,
it is known that GPS transmissions can be "spoofed" by an external
transmitter, to cause a GPS receiver to report an incorrect
location.
[0008] It is an object of the present invention to provide means by
which the integrity of metadata attached to primary data by a
consumer electronic device may be verified with various levels of
confidence.
SUMMARY OF THE INVENTION
[0009] According to the present invention, there is provided a
system for attributing a confidence level to time and location
metadata associated with primary data, the system including a
plurality of mobile capture devices and a mobile data communication
network allowing data transfer between the mobile capture devices,
[0010] each mobile capture device including at least one sensor for
capturing primary data, and being adapted to provide metadata
specifying at least the time and location relating to captured
primary data, and each mobile capture device further including at
least one further sensor for measuring at least one environmental
parameter, [0011] each mobile capture device being adapted to carry
out the steps of: [0012] capturing primary data using the at least
one sensor; [0013] associating metadata with the primary data, the
metadata specifying at least the time and location of the capture;
and [0014] measuring and storing at least one environmental
parameter at the time and location of the capture, and associating
the measured environmental parameter with the primary data, [0015]
in response to a trigger, [0016] and each mobile capture device
being adapted to carry out the steps of: [0017] measuring and
storing at least one environmental parameter; and [0018]
transmitting the measured environmental parameter on the
communication network, [0019] in response to a remote command,
[0020] and the system including at least one device connected to
the data communication network and being adapted to: [0021] in
response to a capture of primary data being made by a mobile
capture device forming part of the system, [0022] carry out the
steps of: [0023] identifying other mobile capture devices in a
similar location at a similar time to the capture device making the
primary data capture; [0024] requesting and receiving environmental
data from other mobile capture devices identified; [0025] comparing
environmental data received from other mobile capture devices with
the environmental data measured by the device capturing the primary
data, and assigning a confidence level to the time and location
metadata associated with the primary data based on the
comparison.
[0026] The environmental data could be one or more of, for example,
temperature, humidity, barometric pressure, light level, etc.
Environmental data could also include for example visible WiFi
networks and cell towers. By comparing environmental data measured
by the device capturing, for example, a photograph, with
environmental data captured by other devices in a similar location
at a similar time, the location metadata attached to the photograph
by the capturing device can be given a confidence score.
[0027] A capture device responds to a trigger (for example a user
command) by taking (for example) a photograph and recording time
and location metadata. The time is typically taken from an internal
clock on the capture device, which is synchronised at intervals
with a network time server. The position information is usually
taken from for example a GPS or GLONASS receiver on the device.
[0028] When a capture is made by a particular device, this triggers
action in other parts of the system. In particular, other nearby
capture devices will measure and report environmental data for the
purposes of comparison. The users/owners of these other nearby
devices do not need to take any action, and in most cases do not
even need to be specifically aware that environmental data is being
captured and reported at a particular time, provided that they have
previously consented to the collection of data, and provided that
the data collected is suitably anonymised so that it cannot be
linked back to a particular user. The trigger may be a direct user
command on the capture device, or alternatively devices could be
set on timed triggers, for example to take a photograph every hour,
or in response to a motion sensor, or any other trigger.
[0029] The device which identifies other nearby devices and makes
comparisons could be a server device, or alternatively could be a
capture device--either the same capture device capturing the
relevant primary data or a different capture device in the system.
Depending on the wider context of the system and the trust model,
it may be acceptable for the same capture device to play a close
role in verifying its own data, in cases where the problem being
addressed is specifically external devices fooling a capture device
into reporting an inaccurate location, rather than untrustworthy
capture devices.
[0030] Each mobile capture device may be in the form of a modern
mobile telephone, including in particular a processor, and running
application software to cause it to carry out the steps required by
the system of the invention.
[0031] The confidence level in some embodiments may be a binary
value indicating either that some confidence threshold has been met
or not, i.e. that the time and location metadata attached to the
primary data is either verified or not, or alternatively in other
embodiments a numeric value or other multi-level output may be
provided, indicating the level of confidence in the time and
location metadata.
[0032] Other devices may be identified within a similar location,
for example a radius of one mile, to provide data for
cross-verification. In urban areas, there may be a large number of
devices very close by, for example within a few hundred metres. In
less-populated areas there are likely to be fewer other devices and
the range may need to be extended. A "similar location" may
therefore be defined dynamically--only very close devices might be
used where the area is densely populated with many devices, whereas
in a less populated area a "similar location" may include devices
further away.
[0033] For a particular comparison of an environmental parameter x
being made with another device which is a distance of .delta.p
away, a condition
.delta. x .delta. p < Max ##EQU00001##
may be checked to provide a binary answer. If the difference in the
environmental parameter .delta.x divided by the distance between
the devices is less than a threshold, then that particular
cross-verification is successful--the environmental data collected
by the capturing device is said to be consistent with environmental
data collected by another nearby device.
[0034] In some embodiments, there may also be a difference in time
between measurements of environmental data on different devices. In
that case the time difference .delta.t can also be accounted for in
the comparison. However, it is preferable for time differences to
be very small if possible. This is achieved by requesting
environmental data from other devices for comparison immediately
when a capture is made. In some embodiments, the user could even
trigger this information to be requested from other devices in
advance, and receive feedback when the capture device in use is
able to produce a "verified location", and then choose to take a
photograph. Otherwise, the environmental data from other devices
should be obtained as soon as possible after a capture is made. In
cases where there is no network connectivity available at the time
of capture, environmental data from other devices might be delayed,
but any significant delay can be taken account of and will reduce
the confidence level of the location data.
[0035] If a numeric or multi-level, rather than binary answer is
required, then instead of comparing with a threshold the ratio
.delta. x .delta. p ##EQU00002##
can be used as a confluence score, or as an input to further
functions used to calculate a confidence score.
[0036] In preferred embodiments multiple different environmental
parameters may be used. In that case, for a particular comparison
with another device the difference in a weighted sum of two or more
parameters over the difference in distance may be used:
.delta. ( a x + by + nz N ) .delta. p ##EQU00003##
[0037] In this example, each parameter x, y . . . , z may be given
a different weight a, b . . . n. The weighted sums in each position
are differenced and then divided by the difference in position.
Again, the result of this can be compared to a threshold to provide
a binary answer, or may be used in conjunction with further
functions to provide a numeric or multi-level answer.
[0038] Where multiple other devices have reported environmental
data, the single- or multi-parameter ratio may be calculated
between the capturing device and each other device. The results may
then be combined in various ways. For example, in some embodiments
the condition
.delta. x .delta. p < Max or .delta. ( a x + by + nz N ) .delta.
p < Max ##EQU00004##
might have to be met for every other comparison with every other
device in order to declare the position as verified. In other
embodiments a threshold, for example 80% of devices having
consistent data, may be enough. In yet other embodiments a numeric
or multi-level confidence score may be derived from the absolute
number or proportion of other devices which have consistent
environmental data.
[0039] Different devices forming part of the same system may have
different hardware sensors and different capabilities. Comparisons
can be made with sets of environmental parameters which are common
to both devices. For example, if one device can measure
temperature, light level and pressure and another device can
measure temperature, light level and humidity, then a comparison
involving data from these two devices could use temperature and
light level but not humidity or pressure.
[0040] These conditions assume that the environmental parameters
reported by devices are numeric. Many relevant parameters are
numeric data, for example temperature, barometric pressure, light
level etc. However, some embodiments may use more complex data, for
example WiFi networks and/or cell towers seen in the area.
Different types of comparisons may therefore be needed to handle
this type of data. For example, devices could report lists of
`visible` WiFi networks. From these lists three numbers can
immediately be derived--number of networks seen only by device a,
number of networks seen only by device b, and number of networks
seen by both devices. Where the devices report a location closer
than a certain threshold (for example a few tens of meters), a high
number of networks seen by both devices when compared to the number
of networks seen only by one device may be an indicator of high
confidence in the location.
[0041] In addition to cross-verifying with data from other devices
in the system, certain data may be compared with third-party data
sources. For example, the OpenCellID database provides information
about cell towers and WiFi networks corresponding with locations.
By comparing the cell towers and/or WiFi networks seen by the
capturing device (or even by another nearby device forming part of
the same system) with reference data from a trusted third party
data source, a further level of confidence may be achieved.
[0042] As another example, GPS data provides not only
two-dimensional position (i.e. latitude and longitude) but also
elevation. The combination of latitude, longitude and elevation can
be compared to third party mapping data to further increase
confidence. If the GPS position is recording for example an
elevation of just 50 m above sea level but mapping data shows that
the two-dimensional position is in a mountain range, then the
purported location may be unreliable.
[0043] As a further example, certain environmental data collected
by the capturing device can be compared with the purported location
data by making use of known relationships. For example, GPS
position may indicate a particular elevation, and as described
above this may correspond with the two dimensional GPS position and
mapping data. Where the capture device includes a pressure sensor,
the pressure measured by the pressure sensor may be used to
calculate an estimated height, which may also be compared to the
measured/mapped position. The following formula may be used to
estimate the height from a pressure reading:
h = 2 7 3 . 1 5 + T 0 0 . 0 0 6 5 ( 1 - ( P P 0 ) 1 5.255 )
##EQU00005##
[0044] Where T.sub.0 is standard temperature (15.degree. C.) and
P.sub.0 is reference pressure (1013.25 hPa). P is the measured
pressure and h is the estimated height.
DESCRIPTION OF THE DRAWINGS
[0045] For a better understanding of the present invention, and to
show more clearly how it may be carried into effect, preferred
embodiments will now be described with reference to the
accompanying drawings, in which:
[0046] FIG. 1 shows an outline schematic of a mobile capture device
forming part of the system of the invention;
[0047] FIG. 2 shows an outline schematic of an embodiment of the
system of the invention; and
[0048] FIG. 3 is a flow chart showing the processes carried out by
various components of the system of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0049] Referring firstly to FIG. 1, a mobile smartphone is
indicated at 10. The smartphone is a mobile capture device in the
system of the invention. Different models of smartphone of course
have different features, but critical to the system of the
invention are that the smartphone 10 includes a processor 12, data
storage 14, at least one sensor for capturing primary data (for
example a camera 16 and a microphone 18), a positioning system (for
example a GPS receiver 20) and at least one sensor for measuring an
environmental parameter, for example a pressure sensor 22.
[0050] In FIG. 2, an overview of a whole system is shown in
outline. The system 100 includes multiple mobile capture devices
10, 10', 10''. In most embodiments, each mobile capture device 10
would be a mobile smartphone conforming to at least a minimum
specification. Each capture device 10 in the system could therefore
include slightly different hardware components and capabilities.
All of the mobile capture devices are connected to a data
communications network 50. The network 50 is not described in
detail but in most embodiments will be a complex network or
internetwork including multiple components. All devices connected
to the network can communicate with each other.
[0051] A server device 60 is shown as a separate device, also
connected to the network. There is no reason in principle why one
or more of the mobile capture devices 10 could not perform the role
of the server device, but in this embodiment a dedicated device is
illustrated.
[0052] Referring now to FIG. 3, the process of creating and
verifying primary data with associated time and location metadata
is illustrated. Note that this process involves actions on the
"capturing device" 10, and "other capture devices" 10', 10''. The
term "capturing device" is used to mean one of the mobile capture
devices in the system which is currently being used to capture
primary data (e.g. take a photograph). Any of the mobile capture
devices at any time may take this role, normally in response to a
user command or other trigger.
[0053] At step 102 the capturing device 10 captures primary data.
This is typically in response to a user command but in some
embodiments another trigger, for example a time trigger, a motion
sensor or a remote trigger might set off the process on the
capturing device. Capturing primary data typically means taking a
photograph, or making a video recording or a sound recording. The
primary data is stored by the capturing device 10 in data storage
14.
[0054] At step 104 time and location metadata is associated with
the primary data. The time typically comes from an internal clock
on the capturing device 10, and the location from the GPS receiver
20. Associating the metadata with the primary data can be done by
embedding it into the primary data file, associating it in a
database, etc. In some embodiments cryptographic techniques may be
used to bind the primary data and metadata together and prevent
tampering. Various other security safeguards may be built into the
device to attempt to ensure that the time and location metadata is
difficult to tamper with or "spoof".
[0055] Where the primary data is a video or sound recording, i.e.
data which is captured over a period of time, it may be desirable
to repeat step 104 at intervals, since it is possible for the
capturing device 10 to move significantly during a long
recording.
[0056] At step 106 an environmental parameter is measured by the
capturing device 10. This parameter could be for example the
barometric pressure which is measured by the pressure sensor 22 on
the capturing device. In most embodiments, most of the mobile
capture devices in the system will have multiple sensors for
measuring different environmental parameters, and the capturing
device will measure as many environmental parameters as it can.
Environmental parameters could be for example temperature, light
level, barometric pressure, WiFi networks visible, cell towers
visible, etc.
[0057] At step 108 a message is transmitted to the server device
60. In this embodiment a server device 60 has a role in
coordinating the process, but a decentralised embodiment is also
envisaged. The message transmitted to the server at step 108
includes the position of the capturing device, and triggers the
process of cross-verification. The server 60 takes the transmitted
position and identifies nearby other mobile capture devices 10',
10'' at step 110. In some embodiments the server may constantly
keep track of the positions of all devices in the system, in other
embodiments nearby devices may be identified by broadcasting a
message to all devices on the system and requesting replies from
those close to a particular position. The server may start by
trying to identify devices very close (say within a few tens of
metres) to the position of the capturing device 10, but in rural or
sparsely-populated areas the server may have to expand the search
range to find devices. The server 60 must also identify other
devices which are compatible with the capturing device 10, in the
sense that to provide useful cross-verification information,
devices must be able to measure at least one environmental
parameter in common with the capturing device. Of course, in
embodiments where visible cell towers and/or WiFi networks are used
as environmental parameters, almost all devices will be compatible
at least to this extent.
[0058] Once compatible devices in a suitable area have been
identified, the server transmits a message to those devices
requesting measurements of environmental parameters. At step 112
each other device measures the requested environmental parameters,
and at step 114 the measured parameters are transmitted back to the
server 60. If the server device does not already have it, a precise
position (typically obtained from a GPS receiver on each device) is
also transmitted back to the server 60.
[0059] At step 116 the server compares environmental data. This
could be by the weighted sum method described in more detail
above--the server determines the result of:
.delta. ( a x + by + nz N ) .delta. p < Max ##EQU00006##
[0060] and if the difference in the weighted sum over the
difference in position is less than a threshold for a particular
comparison between data from the capturing device and data from
another device, then that other device is effectively in agreement
with the capturing device. A confidence level may be assigned
depending on, for example, the number of other devices which are in
agreement.
[0061] At step 118 a result is returned. In different embodiments
this result may be transmitted back to the capturing device 10,
stored in a database, embedded in the primary data with
cryptographic safeguards, etc. The result may simply be a binary
"verified" or "unverified" depending on whether threshold
conditions for the consistency of data have been met. Alternatively
a numeric or multi-level result may be calculated in different
embodiments.
[0062] The system of the invention preferably forms part of a wider
system for creating verifiable data. Such a system should contain
security safeguards to prevent tampering with data and ensure
devices can be trusted. An example of such a system is disclosed in
the Applicant's co-pending application number PCT/IB2018/050036
filed on 3 Jan. 2018.
[0063] The system of the invention allows for confidence in time
and position metadata which is attached to, for example, a
photograph. Where the position information attached to a photograph
is shown to have been verified by the system of the invention, an
increased level of confidence can be given to that information,
because the system of the invention makes it very difficult to
attach false metadata and have that metadata verified, since to do
so would involve compromising a large number of third party
devices.
[0064] The embodiment described is by way of example only. The
invention is defined in the claims.
* * * * *