U.S. patent application number 14/000439 was filed with the patent office on 2014-02-27 for broadcasting an information signal having special content for triggering an appropriate action in a user device.
This patent application is currently assigned to CIVOLUTION B.V.. The applicant listed for this patent is Jaap Andre Haitsma, Martijn Maas, Alex Dick Terpstra. Invention is credited to Jaap Andre Haitsma, Martijn Maas, Alex Dick Terpstra.
Application Number | 20140059591 14/000439 |
Document ID | / |
Family ID | 44558493 |
Filed Date | 2014-02-27 |
United States Patent
Application |
20140059591 |
Kind Code |
A1 |
Terpstra; Alex Dick ; et
al. |
February 27, 2014 |
BROADCASTING AN INFORMATION SIGNAL HAVING SPECIAL CONTENT FOR
TRIGGERING AN APPROPRIATE ACTION IN A USER DEVICE
Abstract
The problem is solved by a method for broadcasting a broadcast
signal, comprising generating an information signal having in time
a first content up to a certain time and a second content after
this time. The information signal is broadcast as a broadcast
signal via a first communication link At least one first feature is
being provided with respect to the second content, for example an
advertisement. The second content is detected in the information
signal using the at least one first feature. On detection of the
second content in the information signal at least one second
feature is extracted from the first content in the information
signal preceding the second content. The at least one second
feature is sent to a user device using a second communication link,
different from the first communication link, the second
communication link being faster than the first communication
link
Inventors: |
Terpstra; Alex Dick; (Heeze,
NL) ; Haitsma; Jaap Andre; (Santiago, CL) ;
Maas; Martijn; (Eindhoven, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Terpstra; Alex Dick
Haitsma; Jaap Andre
Maas; Martijn |
Heeze
Santiago
Eindhoven |
|
NL
CL
NL |
|
|
Assignee: |
CIVOLUTION B.V.
Eindhoven
NL
|
Family ID: |
44558493 |
Appl. No.: |
14/000439 |
Filed: |
February 21, 2012 |
PCT Filed: |
February 21, 2012 |
PCT NO: |
PCT/NL12/50102 |
371 Date: |
November 1, 2013 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61446161 |
Feb 24, 2011 |
|
|
|
Current U.S.
Class: |
725/32 |
Current CPC
Class: |
H04N 21/435 20130101;
H04N 21/8586 20130101; H04N 21/4348 20130101; H04N 21/458 20130101;
H04N 21/6175 20130101; H04N 21/812 20130101; H04N 5/44 20130101;
H04N 21/23418 20130101; H04N 21/44016 20130101 |
Class at
Publication: |
725/32 |
International
Class: |
H04N 21/234 20060101
H04N021/234 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 24, 2011 |
NL |
2006291 |
Claims
1.-14. (canceled)
15. Method for broadcasting a broadcast signal, comprising:
generating an information signal having a first content and
subsequently a second content; broadcasting the information signal
via a first communication link; generating at least one previously
determined first feature for the second content; detecting of the
second content in the information signal using the at least one
previously determined first feature; generating at least one second
feature for the first content of the information signal preceding
the second content upon detection of the second content in the
information signal; sending the at least one second feature for the
first content to a user device via a second communication link.
16. Method according to claim 15, wherein detecting comprises:
extracting at least one third feature from the information signal;
comparing the at least one third feature with the at least one
previously determined first feature for the second content;
generating a detection signal if the at least one third feature
matches the at least one first feature.
17. Method according to claim 16, wherein the at least one
predetermined first feature comprises a first fingerprint for the
second content; and wherein the at least one third feature from the
information signal comprises a second fingerprint.
18. Method according to claim 16, wherein the at least one
predetermined first feature comprises a first payload of a first
watermark for the second content, wherein the at least one third
feature comprises a second payload of the first watermark from the
information signal; and wherein extracting the at least one third
feature comprises detecting the first watermark; and determining
the second payload upon detection.
19. Method according to claim 15, wherein the generating of the at
least one second feature for the first content of the information
signal preceding the second content comprises: buffering the
information signal; and extracting the at least one second feature
from the buffered information signal of the first content preceding
the second content upon detection of the at least one first feature
in the information signal.
20. Method according to claim 19, wherein the at least one second
feature is a third fingerprint.
21. Method according to claim 19, further comprising providing the
information signal with a second watermark (W) with a payload,
wherein the method is being executed with the watermark information
signal; wherein extracting the at least one second feature from the
buffered information signal comprises detecting the second
watermark (W) and determining the payload of the second watermark
(W); wherein the at least one second feature comprises the payload
of the second watermark (W).
22. Method according to claim 15, wherein the generating of the at
least one second feature for the first content of the information
signal comprises: extracting at least fourth feature from the
information signal; buffering the at least one fourth feature;
selecting the at least one second feature from the buffered at
least one fourth feature upon detection of the at least one first
feature in the information signal.
23. Method according to claim 22, wherein the at least one fourth
feature is a fourth fingerprint.
24. Method according to claim 22, further comprising: providing the
information signal with a second watermark (W) having a payload,
wherein the method is executed with the watermarked information
signal; wherein extracting of the at least one fourth feature
comprises detecting the second watermark in the watermarked
information signal and determining the payload of the second
watermark; and wherein the at least one fourth feature is the
determined payload of the second watermark.
25. Method according to claim 15, further comprising: providing the
information signal of a second watermark having a payload, wherein
generating the at least one second feature for the first content of
the information signal comprises: buffering the payload of the
second watermark (W); selecting the at least one second watermark
from the buffered payload of the second watermark (W) upon
detection of the at least one first feature in the information
signal.
26. Method according to claim 15, further comprising: providing the
information signal with a second watermark (W) having a payload,
wherein the payload of the second watermark comprises a first time
stamp; and wherein generating of the at least one second feature
for the first content of the information signal comprises:
generating the at least one second feature having a second time
stamp derived from the first time stamp from the payload, such that
it corresponds to a value of the first time stamp associated with
the first content preceding the second content in the information
signal upon detection of the second content.
27. Method according to any one of the claims 15, wherein
generating the at least one second feature comprises generating a
payload of a third watermark (X) upon detection of the second
content; the method further comprising: buffering of the
information signal; and embedding the third watermark (X) having
the payload in the buffered information signal in the first content
preceding the second content; and broadcasting the buffered
watermarked information signal via the first communication
link.
28. Broadcast arrangement for broadcasting a broadcast signal,
comprising: a first generator for generating an information signal
having a first content and subsequently a second content; a first
transmitter for broadcasting the information signal as broadcast
signal via a first communication link; a source for generating at
least one first feature with respect to the second content; a
detector for detecting the second content in the information
signal, using the at least one first feature; a second generator
for generating the at least one second feature for the first
content of the information signal preceding the second content upon
detection of the second content in the information signal; a second
transmitter for sending the at least one second feature for the
first content to a user device via a second communication link
wherein the arrangement is further adapted for executing the steps
of the method according to claim 1.
Description
DESCRIPTION
[0001] 1. Field
[0002] The invention relates to a method and system for
broadcasting an information signal having special content for
triggering an appropriate action in a user device.
[0003] 2. Background
[0004] In a broadcasting environment, such as television or radio
broadcasting, a consumer can render the broadcast content broadcast
by a broadcast organisation on a user device, such as a television
set or a radio. With the arrival of additional user devices with
data processing capabilities, such as set top boxes and the like,
user involvement with the content can be enabled. Thus it became
possible to perform a content related action within such a device
based on the broadcast content. Such an action can for example be
substituting a broadcast advertisement, aimed at a general
audience, by a substitute advertisement aimed at a specific
consumer group, or even an individual consumer. The substitute
advertisement may have been obtained via an alternative
communication link. Other actions may include turning on or off
consumer equipment, enabling new levels or cheats in a game,
etcetera. Also user input related to the content can be
enabled.
[0005] Actions as described above can be triggered by detecting the
presence of special content in the broadcast signal. The starting
point of the special content in the information signal is called a
trigger point. The user device adapted for this purpose may have a
separate input for receiving features that enable the device to
detect the trigger point and take the appropriate action.
[0006] A broadcast organisation can add special content to the
content, e.g. a record or a movie, being broadcast to the public,
whereby features by which the associated trigger point can be
detected are previously extracted from the special content. These
features are communicated to the user device. This enables the
broadcaster to insert the special content at any time into the
content knowing that the user device can detect the special content
and let the user device take the appropriate action, independent of
the content preceding the special content or the time on which the
special content is inserted and irrespective of any hickups such as
delays or program changes.
[0007] The detection of the trigger point by the user device, may
however be subjected to latency of a detector circuit within the
user device. It can take seconds or in some cases even minutes to
detect the special content. As a consequence the appropriate action
which the user device is supposed to perform on receipt of the
special content, is disturbed, may be too late, or the substitute
content may be preceded by part of the content that was to be
substituted due to the latency. Furthermore the content preceding
the special content, is normally only known at the moment of
broadcasting.
SUMMARY
[0008] It is therefore an object of the present invention to
overcome the disadvantages as described above.
[0009] The object is achieved by a method for broadcasting a
broadcast signal, comprising generating an information signal
having a first content and a second content after the first
content. The information signal is broadcast as a broadcast signal
via a first communication link. The second content allows a user
device to perform an appropriate action when it is received.
[0010] At least one previously determined first feature is being
generated with respect to the second content, for example an
advertisement. The second content is detected in the information
signal using the at least one first feature. On detection of the
second content in the information signal at least one second
feature is generated for the first content in the information
signal preceding the second content. The at least one second
feature is sent to the user device using a second communication
link, different from the first communication link, the second
communication link being faster and/or having less delay than the
first communication link.
[0011] Using this higher speed, the at least one second feature
arrives at the user device while the first content is still being
received and the second content is yet to be received. Using the at
least one second feature, the first content preceding the second
content can be detected. This allows the user device to detect the
second content before it arrives. The user device can take
appropriate action before or at the moment the second content
arrives at the user device. Thus the appropriate action, such as
advertisement substitution, is performed irrespective of the
detector latency.
[0012] A further advantage of the described method is that no
modification of the user device is required to relieve the detector
latency. The detection of the content preceding the second content,
the actual trigger point, can be performed in a user device
according to the state of the art.
[0013] In an embodiment of the invention, the step of detecting the
second content in the information signal comprises extraction of at
least one third feature from the information signal. This feature
is compared with the at least one first feature for the second
content. A detection signal is generated if the at least one third
feature matches with the at least one first feature. This enables
the detection of the second content solely on the presence of the
second content in the broadcast signal.
[0014] In a further embodiment, the at least one first feature
comprises a first fingerprint of the second content, and wherein
the at least one third feature from the information signal
comprises a second fingerprint. The second content is detected when
the first fingerprint and the second fingerprint match. This allows
the detection of the second content in the information signal to be
efficiently performed on the basis of signal fingerprinting
technology.
[0015] In another further embodiment, a first watermark is used to
identify the second content. The at least one predetermined first
feature now comprises a first payload of the first watermark for
the second content and the at least one third feature comprises a
second payload of the first watermark extracted from the
information signal. The second payload is extracted from the
information signal by detection of the first watermark in the
information signal and determining the second payload on detection
of the first watermark. The second content is detected when the
first watermark is detected and the previously determined first
payload matches with the second payload from the information
signal. This allows the highly reliable detection of the second
content to be performed on the basis of watermarking
technology.
[0016] In an embodiment, the step of generating the at least one
second feature of the first content of the information signal
comprises buffering the information signal and extracting the at
least one second feature from the buffered information signal on
detection of the second content in the information signal. By
buffering the information signal, the first content preceding the
second content is available in the buffer, from which the at least
one second feature can be extracted, such that detection of the
second content is performed in the user device before the actual
arrival of the second content.
[0017] The at least one second feature can be a third fingerprint,
allowing easy detection of the second content in the user device
before it is received on the basis of fingerprinting
technology.
[0018] As an alternative for fingerprinting, the information signal
during broadcast can be provided with a continuously embedded
second watermark with a payload. When the second content is
detected as described above, the payload of the second watermark
can be extracted from the buffered watermarked information signal
by detecting the second watermark, determining the payload, and
using the payload of the second watermark as the at least one
second feature, the at least one second feature corresponding to
the first content preceding the second content as a consequence of
the buffering. This allows the use of a continuously embedded
watermark in the information signal to be used for detection of the
second content in the user device before it is received.
[0019] In another embodiment, the step of generating the at least
one second feature from the first content of the information signal
comprises extracting at least one fourth feature from the
information signal, buffering the at least one fourth feature and
selecting the buffered at least one fourth feature as the at least
one second feature upon detection of the second content as
described above. The at least one second feature corresponds to the
first content preceding the second content in the information
signal due to the buffering of the fourth feature.
[0020] The at least one fourth feature and subsequently the at
least one second feature to be sent to the user device can be a
fingerprint of the content in the information signal.
[0021] As an alternative for fingerprinting, the information signal
during broadcast can be provided with the continuously embedded
second watermark with a payload as described above. In the case
where the second watermark has previously been inserted, before
generating the information signal, when the second content is
detected, the payload of the second watermark can be extracted from
the watermarked information signal as the at least one fourth
feature, by detecting the second watermark, and determining the
payload. The payload of the second watermark is subsequently
buffered. In the case the second watermark is inserted when
generating the information signal, the payload of the second
watermark does not need to be detected and can be buffered while
embedding the second watermark with the payload.
[0022] Upon detection of the second content the buffered payload of
the second watermark is selected as the at least one second feature
corresponding to the first content preceding the second content.
This also allows the use of a continuously embedded watermark in
the information signal to be used for detection of the second
content in the user device before it is received.
[0023] In a variant of the above embodiment, the at least one
fourth feature is equal to the at least one third feature from the
detection process, where the at least one third feature was
obtained by the feature extraction from the information signal for
the detection of the second content. The buffering enables the
selection of the at least one second feature relating to the first
content preceding the occurrence of the second content in the
information signal. Since such features are in the buffer, mere
selection of the appropriate features is sufficient to obtain the
at least one second feature to be send to the user device.
[0024] Using the feature extraction of the detector of the presence
of the second content facilitates easy generation of the at least
one second feature, the at least one second feature being of the
same kind as the at least one third feature extracted from the
information signal.
[0025] In another embodiment, the information signal can be
provided with a second watermark having a payload. The payload can
have a first timestamp, which is continuously updated, indicating
the current time of day and/or date of generating the information
signal. The step of generating the at least one second feature
comprises generating on detection of the second content in the
information signal the at least one second feature comprising a
second timestamp, wherein the second timestamp value is derived
from the timestamp value of the first timestamp such that it
corresponds to a first timestamp value associated with the first
content preceding the second content in the information signal.
This allows an efficient way of generating a feature for the user
device to detect the first content preceding the second content,
without the need of buffering the information signal or the second
watermark payload.
[0026] In yet another embodiment, the step of generating the at
least one second feature comprises generating a payload for a third
watermark upon detection of the second content. The method further
comprises buffering the information signal and embedding the third
watermark in the first content of the buffered information signal
preceding the second content. The watermarked buffered information
signal is subsequently broadcast via the first communication link
to the user device. The payload of the third watermark is sent as
the at least one second feature by the generator to the user device
using the second communication link.
[0027] The user device has previously been provided with the third
watermark. This allows the user device to perform detection of the
second content in the received information signal having the third
watermark and payload received via the second communication link,
such that the watermark and payload can be detected in the first
content before the second content is received.
[0028] In the abovementioned embodiments the at least one second
feature can contain a channel identification and a trigger point
identification indicating respectively the channel on which the
second content is to be received by the user device and the
identification of the start of the second content where an action
is to be performed by the user device corresponding to or
associated with the second content.
[0029] The object of the invention is also achieved in a broadcast
arrangement for broadcasting a broadcast signal, the system
comprising a first generator for generating an information signal
having in time a first content up to a certain time and a second
content after this time. The arrangement further comprises a first
transmitter for broadcasting the information signal as broadcast
signal via a first communication link. The arrangement further
comprises a source for providing at least a first feature with
respect to the second content, a detector for detecting the second
content in the information signal using the at least one first
feature, and a second generator for generating at least one second
feature from the first content of the information signal in time
preceding the second content. The arrangement further comprises a
second transmitter for sending the at least one second feature via
a second communication link for the first content to a user device.
The arrangement is further adapted for executing the steps of the
method described above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1a shows a block diagram of a broadcast system for
broadcasting a broadcast signal according to the state of the
art.
[0031] FIG. 1b shows a timing diagram of a broadcast signal with a
trigger point according to the state of the art.
[0032] FIG. 2a shows a block diagram of a broadcast system for
broadcasting a broadcast signal, providing trigger point data and a
user device for detecting trigger points in the broadcast signal
using the trigger point data according to the invention.
[0033] FIG. 2b shows a timing diagram of a broadcast signal with a
trigger point according to the invention.
[0034] FIG. 3 shows a block diagram of a trigger point detector for
use in a user device according to the state of the art.
[0035] FIG. 4 shows a block diagram of a trigger point detector for
a broadcast arrangement according to the invention.
[0036] FIG. 5a shows a block diagram of a feature generator for a
broadcast arrangement according to the invention.
[0037] FIG. 5b shows a block diagram of an alternative feature
generator for a broadcast arrangement according to the
invention.
[0038] FIG. 5c shows a block diagram of yet an alternative feature
generator for a broadcast arrangement according to the
invention.
[0039] FIG. 6 shows a block diagram of a broadcast arrangement
according to the invention with continuous watermarking.
[0040] FIG. 7 shows a block diagram of a broadcast arrangement
according to the invention with watermarking of the information
signal on detection of a trigger point.
DETAILED DESCRIPTION
[0041] A broadcast system 101, 102a, 102b, 103, 104 according to
the state of the art shown in FIG. 1 a is subdivided in two
subsystems, a broadcast arrangement 101 and a user device 103,
interconnected by two communication links, a first communication
link 102a, 102b being a broadcast link and a second communication
link being a data network connection 104, using for example the
Internet protocol (IP). The broadcast link 102a, 102b is usually a
wireless or radio link, as shown in FIG. 1a, however wired or
partially wired and partially wireless connections can likewise be
applied.
[0042] The broadcast arrangement 101 represents a typical broadcast
infrastructure comprising a content generator 110, which can
generate an information signal 111 with first and second content
from the content storage, which is transmitted 112 via the first
communication link 113, 102a, 102b, 138 to the user device 103. The
content 110 comprises any first content that may be fit for
broadcast distribution, frame oriented television broadcast, or
continuous radio broadcast, such as music records, movies, news
programs, sporting events report etcetera. These items can contain
or can be extended with special second content which enable a user
device 103 to perform a certain pre-programmed appropriate action.
Such special second content can be advertisements, or preselected
scenes in any of the previously mentioned content items.
[0043] The process for introducing the special second content is
not shown in FIG. 1a, since there are various ways to perform this.
It is for example possible to add such special content on the fly,
while the process of broadcasting the main content is in progress.
The content for broadcasting including first and second content can
also be prepared and stored in advance, where for example movies
and other content are mixed with the special second content, and
broadcast at a later time. The special second content can also be
designated in the first content in a script using time slots.
[0044] The beginning of the special second content is defined as a
trigger point. The special second content can be analysed prior to
broadcasting to extract features relating to the trigger point that
enable the user device 103 to detect the special content when the
broadcast signal is received 102b, 130 and take appropriate action.
Such features can either be generated on the fly and transmitted
116 to the user device while the special content is being inserted
into the main content or be stored in a trigger point feature
repository 114 from which these features 115 are transmitted 116 to
the user device 103 via the second communication link 117, 104, 139
before broadcasting the content. In practise, the generation of the
information signal and maintenance of the trigger point feature
repository can be under the control of different organisations such
as a broadcast organisation and an advertisement agent
respectively.
[0045] Additional information relating to the trigger point can be
at least one of a trigger point identification, the desired action
to be taken by the user device 103 receiving it such as
advertisement substitution and can for example also refer to
substitute content. The additional trigger point information can
also be stored in the trigger point feature repository 114 and
subsequently communicated to the user device 103, allowing that
when the trigger point features are detected, the trigger point can
be properly identified and the desired action to be taken. The
additional information can also comprise a channel identification
on which the trigger point is to appear, in order to avoid false
triggering by the user device 103 on receipt of the trigger point
on a different channel then intended, where the appropriate action
was not foreseen.
[0046] Nowadays various user devices 103 have an Internet
connection, so the trigger point features 115 may be transmitted
116 using a data connection 117, 104, 139 via for example, but not
limited to, the Internet using Internet Protocol (IP).
[0047] The exemplary user device 103 of FIG. 1a has an input 138
for the broadcast communication link 102a 102b for receiving the
broadcast content. Receiver 130 restores the information signal 132
broadcast from the broadcast system 101 having the first and second
content. The content is supplied to a rendering device 131 which
for example can be a graphical display unit or a device for
transforming the information signal into a modulated signal for
further processing in for example a television unit.
[0048] Trigger point information relating to the second content
comprising features and optional additional information is received
via input 139 by the receiver 135. The features 136 of the trigger
points are sent to the detector 133. Additional information 137,
such as a trigger point identification or other additional
information is made available to the rendering device 131 for
processing when the associated trigger point is detected.
[0049] FIG. 1b shows an example of an information signal having
first content 118 and second 119. The second content stretches from
time T1 tot time T3. The signal in FIG. 1b has a trigger point at
T1 indicating a change from first content 118 to second content
119, having features 120 stretching from time T1 to time T2 by
which the trigger point may be detected. When this information
signal is received 130 by the user device 103, the trigger point
may be detected 133 using features relating to the trigger point
which have been received from the trigger point repository 114 of
the broadcast system 101. It may take detector 133 from time T1 to
time T2 to receive the features and from T2 to T2+L to detect the
trigger point, the time T2 to T2+L (121) being the detector
latency. The total latency L.sub.tot=T2-T1+L is thus determined by
the time for receiving the trigger point features and time to
detect.
[0050] If the rendering unit 131 is for example instructed to
substitute the second content with a pre-stored advertisement
directed to the individual user of user device 103, then during
time T1 to time T2+L the second content 119 is still displayed to
the user. This is an undesired situation.
[0051] FIG. 3 shows an example of a detector 133 for use in a user
device 103 for detecting trigger points in an information signal
132. The detector 133 receives features 136 relating to trigger
points from the receiver 135 and stores these in a buffer 305.
Extractor 301 extracts features from the information signal, which
features 302 are provided to a matching unit 303. The matching unit
303 matches the features 302 with the features 304 in the buffer
305. A match can be determined by logically comparing the extracted
features 302 with the buffered features 304, or by mathematically
comparing the extracted features 302 with the buffered features.
The latter can involve a correlation function. When a match is
found, a match signal 134 is send to the rendering unit 131, which
can then take the appropriate action.
[0052] FIG. 2a shows a broadcast system with broadcast arrangement
101 according to the invention and the user device 103, the
broadcast arrangement 101 being arranged for broadcasting content
and generating trigger point features for the user device 103. The
broadcast arrangement 101 comprises a trigger point feature
repository 114 and a generator 110 for the information signal 111
having the first and second content. Detector 201 detects a trigger
point, being the start of the second content in the information
signal, using the features 115 from the trigger point repository
114 and produces a match detection signal 202 when a match is
found. A matching function used in detector 201 of the broadcast
arrangement 101 for determining a match between features in the
content of the information signal 111 and the features 115 from the
trigger point repository 114 is similar to the matching function in
detector 133 of the user device 103.
[0053] On detection 202 of a trigger point in the information
signal 111 feature generator 203 extracts features 204 from the
first content 118 preceding the second content 119. These features
204 are then supplied to the transmitter 116, where applicable
completed with additional trigger point information from the
original trigger point 115 such as trigger point identification or
channel identification, and sent via the second communication link
117, 104, 139 to the user device 103.
[0054] In the transmission it is assumed that the broadcast signal
via the first communication link 113, 102a, 102b, 138 is prone to
delay with respect to or is slower than the second communication
link 117, 104, 139. So the trigger point information 204 arrives at
the user device 103 before the trigger point relating to the second
content arrives. The user device 103 can now detect the trigger
point using the received (see 136 in FIG. 1a) new features in the
first content preceding the trigger point i.e. the second content,
before the trigger point has actually arrived at the user
device.
[0055] FIG. 2b shows a timing diagram of the information signal 111
having first content 118 and second content 119, where it is shown
that on detection of the original trigger point in the second
content 119 according to FIG. 1a, the generator 203 can extract
features from the part 206 of the first content in the information
signal 111 preceding the trigger point, starting from time T4 to
T1, which features 204 are transmitted 116 to the user device 103.
Also generator 203 can generate a feature, embed this (see FIG. 7)
in the first content of information signal preceding the second
content and send the feature to the user device 13. The information
signal 132 having the feature is received 130 via the first
communication link 102a, 102b, 138 by the user device 103 where the
feature can be detected 133 using the received feature. By taking
an appropriate time T4 with respect to T1, the total latency
L.sub.tot of detecting the trigger point may be compensated.
[0056] FIG. 4 shows a detector 201 for use in the broadcast
arrangement 101. Extractor 401 extracts features 402 from the
information signal 111. The extracted features 402 are matched in
matching unit 403 with features 115 from the trigger point
repository 114. When a match occurs, using a matching function as
described, the match detection signal 202 is sent to extractor 203.
Additionally the feature repository 114 can contain trigger point
identities associated with the features. Thus detector 201 can
include a trigger point identity associated with the detected
second content in the match detection signal 202.
[0057] The extraction of features can be based on various
techniques, such as fingerprinting and watermarking.
[0058] Fingerprinting is a well known technique in the art of
signal processing, i.e. processing of video and audio signals.
Fingerprinting applies to features determined from the content of
an information signal based on at least one of signal amplitude
level, the signal envelope, frequency content, etcetera for
continuous signals and presence of shapes, movement, colour
composition etcetera for frame based signals. Accordingly in an
embodiment for detector 201, fingerprints 402 extracted 401 from
the information signal 111 can be matched 403 to prestored
fingerprints 115. On a match, detector 201 subsequently outputs the
match detection signal 202 that the second content is detected and
where applicable the trigger point identity value.
[0059] Watermarking is also a well known technique in the art of
signal processing. Watermarking involves embedding additional
information in an information signal using for example a pseudo
random code such that the additional information is hardly visible
and does not disturb the viewer. The watermark can be embedded with
a payload. The payload refers to additional data added to the
watermark. These data may for example contain a time stamp and a
channel identification. This can be performed by adding a timestamp
representing current time of day and/or date, a counter value which
is continuously updated, or identification numbers related to the
content items in the information signal and combinations of these.
Thus enabling identification of and distinguishing between
different parts of the content in the information signal using the
payload.
[0060] The second content can be provided with a watermark, where
the payload is an identification of the trigger point. This enables
the detection of for example various advertisements as second
content having the same watermark, but each having a different
payload. Accordingly in detector 201, extractor 401 detects the
watermark for the second content in the information signal 111 and
extracts the payload.
[0061] Where the payload contains a trigger point identity, it is
now possible for the detector to output the detection of the
watermark and the trigger point identity value as the match
detection signal 202. This is not shown in FIG. 4.
[0062] If detection is to be made on the basis of a selection of
trigger point identities, the payload can be subsequently matched
403 to prestored payloads 115 representing the trigger point
identities for which the user device is to perform the appropriate
action. On a match, detector 201 subsequently outputs the match
detection signal 202 that the second content is detected and where
applicable the trigger point identity value.
[0063] FIG. 5a shows an example of a feature generator 203. The
information signal 111 is stored in buffer 501, such that a certain
history of the information is available for feature extraction. In
other words, the buffered information signal 502 behaves like a
delayed information signal 111. Upon detection of the second
content 202, the extractor 503 extracts the at least one second
features from the buffered information signal 502. The delay of the
buffer 501 is such that the at least one second features can be
extracted from the information signal prior to the presence of the
second content in the information signal. The extracted at least
one second features 204 are then forwarded to transmitter 116 for
transmission 117, 104, 139 to the user device 103.
[0064] FIG. 5b shows an alternative configuration for feature
generator 203. Extractor unit 510 extracts features from the
information signal 111. The features 511 are stored in buffer 504,
providing sufficient delay for selector 506 to select upon
detection of a match 202 in detector 201 the features 505 from
buffer 504 corresponding to the first content preceding the trigger
point, relating to the original trigger point in the information
signal 111. The selected features are then forwarded as the at
least one second features 204 to the transmitter 116 for
transmission 117, 104, 139 to the user device 103.
[0065] FIG. 5c shows another alternative configuration for feature
generator 203, where the at least one second feature to be sent is
of the same type as the at least one third feature used for
detection of the second content. Feature generator 203 uses the
output 402 of the extractor unit 401 of detector 201 for obtaining
features from the information signal 111. The features 402 are
stored in buffer 507 providing sufficient delay for selector 509 to
select upon detection of a match 202 in detector 201 the features
508 from buffer 507 corresponding to the first content preceding
the trigger point, relating to the original trigger point in the
information signal 111. The selected features are then forwarded as
the at least one second features 204 to the transmitter 116 for
transmission 117, 104, 139 to the user device 103.
[0066] In the description of FIGS. 5a-5c the extractors 401, 503
and 510 can relate to fingerprinting. Thus the features 402, 511
and subsequently the at least one second feature 204 can be
features obtained through a fingerprinting process.
[0067] Alternatively in the description of FIGS. 5a-5c the
extractors 401, 503 and 510 can relate to watermarking. Thus the
features 402, 511 and subsequently the at least one second feature
204 can be a payload obtained through a watermarking extraction
process. Where for example the first content is provided with a
watermark having a payload, extractors 401, 503 or 510 can detect
the watermark and extract the payload, which payload is forwarded
as feature 204 allowing the user device 103 to detect the trigger
point, i.e. the second content, in advance of the appearance of the
second content.
[0068] Since for example advertisements may be present on various
broadcast channels at the same time, it is undesirable that the
user device takes action on a trigger point appearing on the wrong
channel. It was already mentioned that addition trigger point
information can be provided via the second communication link 117,
104, 139 together with the at least one second features by which
the trigger point is to be detected. Channel identification
constitutes such additional information. Furthermore, to make sure
that the channel can be unambiguously identified in the user device
103, the broadcast signal 113 can be provided with a watermark
having the channel identification as payload. An example for
watermarking the broadcast signal is shown in FIG. 6.
[0069] FIG. 6 shows a block diagram of a broadcast arrangement
according to the invention with continuous watermarking. Embedder
601 continuously embeds a watermark `W` in the information signal
111 with a payload, where the payload can have a timestamp, the
value of which is continuously updated with the current time of day
and/or date, and optionally a channel identification.
[0070] Detection 201 of the second content, and generation 203 of
the at least one second feature 204 is now performed on the
watermarked information signal 602 as previously described. The
detection 201 in FIG. 6 is after embedding watermark `W`. The
skilled person will understand that detection 201 of the second
content can also take place in the information signal 111 before
embedding 601 the watermark `W`. The embedding 601 of the watermark
is an embodiment for the benefit of generation 203 of the at least
one second feature for the user device 103.
[0071] When the trigger point is detected 202, the current time
stamp value and channel identification information can be included
in the at least one second feature 204, in addition to the features
(fingerprints) of the trigger point. At the user device 103, the
watermark W can continuously be detected. In case of detection 133
of the trigger point, for example by means of fingerprint matching,
the time stamp and channel identification in the payload can aid in
checking the channel and time, or may be used to speed up
detection.
[0072] At the time of detection 202 of the trigger point, the
feature generator 203 can optionally use the current timestamp
and/or channel identification to provide the user device 103 with
an alternative at least one second feature. The timestamp value
taken from the payload 603 represents the time of detection 202 of
the second content. The at least one second feature 204 can be
generated using the current timestamp value to derive a timestamp
value corresponding to the timestamp value of the watermark `W`
payload associated with the first content preceding the trigger
point by for example subtracting a time proportional to the elapsed
time between the presence of the first content and the detection of
the second content from the timestamp value associated with the
detection of the second content. The derived timestamp value and
where applicable further specifics of the trigger point such as
trigger point identification and channel identification can be sent
to the user device 103. The skilled person will understand that a
similar result can be achieved using a counter value in the payload
which is updated at regular intervals whereby the different parts
of the content in the information signal 602 can be identified.
[0073] The user device 103, continuously monitoring the watermark W
in the received information signal 132 detects the payload and
matches the timestamp value in the payload with the derived
timestamp value received from the broadcast arrangement 101 and
performs its appropriate action 131 accordingly, before the trigger
point is received.
[0074] FIG. 7 shows a block diagram of a broadcast arrangement
according to the invention with watermarking of the information
signal on detection of a trigger point. The information signal 111
is delayed in buffer 701. When the second content is detected 201,
the feature generator 203 generates a payload 204. This is payload
is added to watermark X and embedded in the first content preceding
the trigger point, in the delayed information signal 702. The
payload can contain an identity of detected trigger point detected
by detector 201, or may be of general form including time stamp and
channel identification as described under FIG. 6. The at least one
second features 204 are now formed by the payload in watermark X in
the first content instead of the fingerprints. In the user device
103, the detection 133 is performed on the payload instead of
fingerprints.
[0075] Alternatively, it may be considered to generate 203 a unique
watermark upon detection 202 of the second content and embed 703
this watermark in the delayed information signal 702 and send the
unique watermark as at least one second feature 204 to the user
device 103. The user device 103 can in such case detect 133 the
trigger point using the unique watermark.
[0076] The embodiments described above are given by example only.
Variations to these embodiments can be obviously made by the
skilled person, without departing from the scope of the invention
as set out by the following claims.
* * * * *