U.S. patent application number 14/634147 was filed with the patent office on 2015-07-02 for system for insertion of locally cached information into a received broadcast stream.
The applicant listed for this patent is Sirius XM Radio Inc.. Invention is credited to Paul D. Marko.
Application Number | 20150189369 14/634147 |
Document ID | / |
Family ID | 39512290 |
Filed Date | 2015-07-02 |
United States Patent
Application |
20150189369 |
Kind Code |
A1 |
Marko; Paul D. |
July 2, 2015 |
SYSTEM FOR INSERTION OF LOCALLY CACHED INFORMATION INTO A RECEIVED
BROADCAST STREAM
Abstract
A method and apparatus are provided for receiving a broadcast
comprising a plurality of program channels and generating a
playback stream using at least one of a buffered program channel
and stored indexed content (e.g., commercials, programs, songs) for
insertion. Control data controls which receivers insert which
indexed content and when the indexed content is inserted into a
received program channel, allowing for playback of songs from
playlists, tiered subscription services, and sponsorship of
broadcast program channels to provide market-directed content to
selected receivers and listeners. Buffer management operations
prevent uncontrolled buffer growth and commercial content avoidance
through rapid channel changes.
Inventors: |
Marko; Paul D.; (Pembroke
Pines, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sirius XM Radio Inc. |
New York |
NY |
US |
|
|
Family ID: |
39512290 |
Appl. No.: |
14/634147 |
Filed: |
February 27, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14032400 |
Sep 20, 2013 |
8973031 |
|
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14634147 |
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12000198 |
Dec 10, 2007 |
8544038 |
|
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14032400 |
|
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60873599 |
Dec 8, 2006 |
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Current U.S.
Class: |
725/32 |
Current CPC
Class: |
H04N 21/438 20130101;
H04L 65/604 20130101; H04N 21/4331 20130101; H04N 21/812 20130101;
H04N 21/44004 20130101; H04N 21/8455 20130101; H04N 21/8456
20130101; H04N 21/4325 20130101; G11B 27/034 20130101; H04L 65/4076
20130101; H04H 20/40 20130101; G11B 27/105 20130101; G11B 27/3027
20130101; H04L 65/4015 20130101; H04N 21/44016 20130101; H04H
20/106 20130101; H04N 21/8126 20130101 |
International
Class: |
H04N 21/433 20060101
H04N021/433; H04N 21/845 20060101 H04N021/845; H04N 21/44 20060101
H04N021/44; H04N 21/438 20060101 H04N021/438; H04N 21/81 20060101
H04N021/81; H04N 21/432 20060101 H04N021/432 |
Claims
1. A method of inserting content into a received content stream for
playback comprising: receiving a content stream comprising at least
one program channel for playback and processing the received
content stream for playback at a user's receiver in a playback
stream; determining changes between program channel content
segments in the program channel; receiving indexed content segments
that can be inserted into the playback stream at potential
insertion points between selected ones of the program channel
content segments; receiving control data indicating which of the
indexed content segments to store at the receiver and insert into
the playback stream; storing selected ones of the received indexed
content segments at the receiver in accordance with the received
control data; generating the playback stream using the program
channel; determining which of the stored indexed content segments
are to be inserted into the playback stream; pausing the program
channel at a selected one of the potential insertion points during
playback of the playback stream, and inserting a selected one of
the stored indexed content segments into the playback stream in
accordance with the control data; buffering the program channel;
and determining at the receiver which of the buffered program
content segments to playback when resuming the playback of the
program channel after the inserting, the buffered program channel
being time delayed relative to the received content stream during
playback due to the inserted indexed content segment.
2. A method as claimed in claim 1, wherein the receiving indexed
content segments comprises receiving the indexed content segments
via a delivery method different from the content stream.
3. A method as claimed in claim 2, wherein the delivery method is
via a physical programming interface, a portable memory device, a
wired or wireless transport link different from a link used to
deliver the content stream, a WiFi link, and a Bluetooth.RTM.
link.
4. A method as claimed in claim 1, wherein the receiving indexed
content segments comprises receiving them as part of the content
stream, the content stream being deceived via a wired or wireless
link.
5. A method as claimed in claim 1, wherein the potential insertion
points are content indent pointers corresponding to at least one of
changes or breaks between content segments in the received content
stream, changes or breaks between content segments in a stream
decoded from the received content stream, a point in time in the
received content stream, a point in a packetized stream, a point in
a transport layer stream comprising the content stream, and a point
in a service layer stream corresponding to the received content
stream.
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 14/032,400, filed on Sep. 20, 2013, which is a
continuation of U.S. patent application Ser. No. 12/000,198, filed
on Dec. 10, 2007, which claims the benefit of U.S. provisional
application Ser. No. 60/873,599, filed Dec. 8, 2006; the entire
contents of each application being incorporated herein by
reference.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] Related subject matter is disclosed and claimed in U.S.
patent application Ser. No. 09/695,226, filed Oct. 25, 2000 (now
issued as U.S. Pat. No. 7,180,917), and U.S. patent application
Ser. No. 11/892,475, filed Aug. 23, 2007 (now issued as U.S. Pat.
No. 7,822,381), the entire contents of which are incorporated
herein by reference.
FIELD OF THE INVENTION
[0003] The present invention relates to a system and method for
implementing tiered subscription services for subscribers to
digital broadcasting services. More particularly, the present
invention relates to a broadcast system configured to allow
commercial or other content cached locally at receivers to be
selectively added to a received broadcast stream based on a
subscription level or tier, and for management of locally buffered
received content as cached content is inserted into the stream
output from the buffer and selected buffered broadcast segments are
dropped or skipped from playback.
BACKGROUND OF THE INVENTION
[0004] A number of providers of broadcast content (e.g., Satellite
Digital Audio Service (SDARS) provider XM Satellite Radio Inc.)
offer subscription services such as a monthly fee for reception of
broadcast content that is primarily commercial free. Some users,
however, may find the monthly fee amount to be cost prohibitive,
but would consider paying for a broadcast service having a higher
percentage of commercial content but a lower subscription fee.
[0005] A need therefore exists for a broadcast system that can
offer different subscription rates that are based on different
levels of commercial content being provided to the subscribers with
the broadcast content.
[0006] A tiered subscription broadcast system is described in U.S.
Patent Application Publication No. US 2006/0190970, to Hellman. In
this system, a receiver plays back either received broadcast
content in real-time or substituted commercial content. To achieve
real-time playback of the received broadcast stream, a real-time
broadcast segment is selected to be dropped and commercial content
substituted therefor, along with the addition of interstitial
content as needed to make up the difference in the durations of the
substituted commercial content and the segment dropped from the
received broadcast stream to accommodate the substitution of
commercial content. This system has the drawback that the real-time
broadcast segment which is dropped is typically a song of 3-4
minutes in length, requiring substitution of 3-4 minutes of
back-to-back commercials. Since many listeners would be
dissatisfied with such long continuous commercial breaks, a need
exists to enable the insertion of shorter commercial breaks, which
may be as little as 5 seconds in duration.
SUMMARY OF THE INVENTION
[0007] Exemplary embodiments of the present invention address at
least the above problems and/or disadvantages and provide at least
the advantages described below.
[0008] In accordance with an exemplary embodiment of the present
invention, a method of inserting content into a received broadcast
stream for playback is provided that comprises receiving a content
stream comprising at least one program channel for playback and
processing the received content stream for playback at a user's
receiver in a playback stream, determining changes between program
channel content segments in the program channel, receiving indexed
content segments that can be inserted into the playback stream at
potential insertion points between selected ones of the program
channel content segments, receiving control data indicating which
of the indexed content segments to store at the receiver and insert
into the playback stream, storing selected ones of the received
indexed content segments at the receiver in accordance with the
received control data, generating the playback stream using the
program channel, determining which of the stored indexed content
segments are to be inserted into the playback stream, pausing the
program channel at a selected one of the potential insertion points
during playback of the playback stream, and inserting a selected
one of the stored indexed content segments into the playback stream
in accordance with the control data, buffering the program channel,
and determining at the receiver which of the buffered program
content segments to playback when resuming the playback of the
program channel after the inserting, the buffered program channel
being time delayed relative to the received content stream during
playback due to the inserted indexed content segment.
[0009] In accordance with aspects of an exemplary embodiment of the
present invention, the receiving indexed content segments comprises
receiving the indexed content segments via a delivery method
different from the content stream. For example, the delivery method
is via a physical programming interface, a portable memory device,
a wired or wireless transport link different from a link used to
deliver the content stream, a WiFi link, and a Bluetooth.RTM.
link.
[0010] In accordance with an aspect of an exemplary embodiment of
the present invention, the receiving indexed content segments
comprises receiving them as part of the content stream, whereby the
content stream being deceived via a wired or wireless link.
[0011] In accordance with another aspect of an exemplary embodiment
of the present invention, the potential insertion points are
content indent pointers corresponding to at least one of changes or
breaks between content segments in the received content stream,
changes or breaks between content segments in a stream decoded from
the received content stream, a point in time in the received
content stream, a point in a packetized stream, a point in a
transport layer stream comprising the content stream, and a point
in a service layer stream corresponding to the received content
stream.
[0012] Other aspects, advantages, and salient features of the
invention will become apparent to those skilled in the art from the
following detailed description, which, taken in conjunction with
the annexed drawings, discloses exemplary embodiments of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other aspects, features, and advantages of
certain embodiments of the present invention will be more apparent
from the following description taken in conjunction with the
accompanying drawings, in which:
[0014] FIG. 1 depicts a multiplexed uplink broadcast transmission
in accordance with an exemplary embodiment of the present
invention;
[0015] FIG. 2 is a block diagram of a receiver in accordance with
an exemplary embodiment of the present invention;
[0016] FIGS. 3, 4 and 5 illustrate buffering of received broadcast
content, insertion of locally cached commercial content and
management of the buffer in accordance with an exemplary embodiment
of the present invention;
[0017] FIGS. 6, 7 and 8 illustrate buffering management during
program channel changes in accordance with an exemplary embodiment
of the present invention; and
[0018] FIGS. 9 and 10 illustrate control messages in accordance
with an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0019] As will be described below in accordance with an exemplary
embodiment of the present invention, a receiver is configured to
store a received broadcast stream into a buffer. In contrast with
the system disclosed in the above-referenced Hellman application,
the receiver only drops broadcast segments from the buffer (or
skips a received broadcast segment in a buffer) after a
corresponding amount of commercial content has been inserted into
the playback stream.
[0020] With reference to FIG. 1, an exemplary multiplexed uplink
for broadcast service transmission 10 is shown. It is to be
understood that the broadcast service stream can be transmitted
wirelessly or via a wired network. For example, the broadcast
service stream can comprise a few hundred different channels of
programming content provided via a selected digital broadcast
service wherein one or more of the channels have indices for
facilitating content insertion to permit users to subscribe to
either a standard service having a selected amount or no commercial
content or a less expensive service having more commercial content
selectively inserted into certain channels using the indices. The
transmitted broadcast stream 10 preferably comprises a plurality of
program channels indicated generally at 20, and one or more
auxiliary channels 22. The program channels 20 and auxiliary
channel(s) 22 are preferably multiplexed using, for example, time
division multiplexing. It is to be understood, however, that the
present invention can be used with a single broadcast stream having
one channel (e.g., an FM radio broadcast channel).
[0021] In the exemplary embodiment illustrated in FIG. 1, an
auxiliary channel 22 preferably provides indexed content to
receivers that can be selectively cached at the receiver. These
cached segments (e.g., commercial segments) are provided to
receivers for later substitution into a received broadcast stream
being played back to a user. The selection of which cached segment
to insert into the buffered stream at a given point during play
back can be performed automatically (i.e., using programmed logic
at the receiver) and depend on one or more factors such as
geographic location of the receiver, user profile (e.g., as
identified when the receiver is activation), time and/or date,
expiration date of the commercial segment, among other factors. The
content segments provided to receivers via the auxiliary channel 22
are preferably uniquely identifiable. The cached content segments
can also be received via a delivery method other than the broadcast
method of the broadcast service, such as through a physical
programming interface, a Wi-Fi or Bluetooth link or delivered via a
portable memory device. The auxiliary channel can also provide
selected music segments for caching at receivers, as described in
U.S. Pat. No. 7,180,917, that are uniquely identifiable and
playlists to provide receivers with lists of selected music
segments for retrieval and playback. The playlisted songs can be
played back at the receiver by being injected as a block of music
segments into a selected buffered channel, or lieu of receiving
live content (e.g., operating the receiver in a My Music mode of
playing back cached content in lieu of a Live Mode in which the
receiver plays back currently received broadcast data).
[0022] With reference to FIG. 2, an exemplary receiver 50 is
provided which is configured to perform content injection in
accordance with an exemplary embodiment of the present invention.
The receiver 50 comprises an antenna 52 or other interface to
receive a broadcast stream (e.g., an SDARS stream) via a wireless
or wired network. In the exemplary embodiment illustrated in FIG.
2, the receiver 50 receives an SDARS stream from a satellite via
antenna 52 that is demodulated, decoded and demultiplexed via the
receiver unit 54. Again, a single broadcast stream can be used such
as an FM broadcast. Commercial or other content (e.g., music
segments and playlists, or program segments such as market-directed
program segments or segments containing channel sponsor material)
received from the auxiliary stream 22 can be stored in the content
cache 56 in accordance with programmed logic provided to a
processor (not shown) in the receiver unit 54. A content stream
representing a single channel 58 demultiplexed from the received
multiplexed broadcast stream is provided to a buffer(s) 62 in FIG.
2. It is to be understood, however, that the receiver 50 is
preferably configured to demultiplex and store a plurality of
program channels from the received broadcast stream into the buffer
62. As described in further detail below in connection with FIGS.
3-5, selected content from the content cache 56 is inserted into a
program channel stream 58 as indicated at 64 in FIG. 2 to create a
playback stream 66 having locally cached commercial segments or
other segments inserted therein. For example, the playback stream
66 can be a Top Tracks program channel received from the broadcast
stream having between 3 and 5 songs dropped therefrom per hour in
lieu of inserted locally cached content. In addition, buffer
management is performed to prevent an infinitely growing buffer 62.
For example, the output buffer 62 can limit received stream
playback delay resulting from cached content insertion by dropping
complete songs as needed, depending on the amount of content that
gets inserted into the playback stream in a given time period.
[0023] In accordance with an exemplary embodiment of the present
invention, the broadcast stream can be SDARS offered at a standard
subscription rate with a selected amount of or no commercial
content in one or more of its programming channels. Content
insertion in accordance with the present invention can be performed
to increase the commercial content in one or more of the SDARS
channels to permit offering the SDARS at a lower rate than the
standard subscription rate.
[0024] With continued reference to FIG. 2, the demultiplexed stream
58 comprises a number of content index pointers (CPIs) 60. The CPIs
correspond to changes or breaks between content segments in a
broadcast stream. These changes or breaks can be represented for
example, by a point in time in the received stream or a particular
point in a packetized stream. The CPIs can correspond to changes in
program segments in the received broadcast stream in general (e.g.,
a demodulated and decoded stream) or packet-by-packet changes in an
intermediately processed packetized stream (e.g., a transport layer
stream or service layer stream). The receivers are programmed to
monitor the received broadcast stream to locate these changes. In
accordance with an exemplary embodiment of the present invention,
the CPIs 60 can correspond to changes in the Program Associated
Data (PAD) that is provided to every track or segment transmitted
via the broadcast stream. In particular, the broadcast program
channels 20 can comprise segments or tracks, each of which has
Program Associated Data (PAD) indicating artist name, song title, a
program ID, a master frame start and end indicator and a content
category (e.g., music genre). For example, SDARS transmits a
preferably unique 32-bit Program ID for each track transmitted over
the air or other broadcast transmission path. A new Program ID
(PID) is preferably provided with each significant artist/title
change. SDARS recording sessions at a receiver can therefore be
divided into separate or individual tracks according to changes in
PID/PAD data detected by the processor in the receiver unit. Thus,
to indicate a CPI, the receiver can be given instructions via the
broadcast stream or other source to insert a selected cached
commercial segment into the received stream at 15 minutes past
every hour. A programmable processor in the receiver 50, in turn,
detects a PAD change at that designated time or the first PAD
change thereafter, pauses the playback of the received stream from
the buffer 62, and inserts the selected commercial track to create
the output stream 66. The cached content can include an index, data
indicating its length or duration, a label or other identifier, and
the content itself (i.e., which can be audio, image or video) with
its corresponding PAD. When playback of the commercial track is
complete, playback of the received stream resumes but now with a
time delay equal to the duration of the inserted commercial
track.
[0025] In accordance with other exemplary embodiments of the
present invention, the selective substitution of locally cached
content exemplified herein can be used to customize the received
broadcast stream for different market segments such as program
channels sponsored by different corporate, government, municipal or
private entities such as SDARS automotive partners, different
industry groups, and entities providing services to foreign
language-speaking listeners. The control data can identify
different receivers or user groups (e.g., using different radio
identifiers or user data defined when a receiver is activated) that
are to receive and insert selected indexed content stream when they
tune to a particular sponsored program channel. For example, an
SDARS automotive partner can sponsor an SDARS program channel
whereby the control data directs the receivers installed in
selected automobiles to insert and play commercials and other
cached program content selected by the sponsor into the sponsored
channel whenever the receivers are tuned to that channel.
Similarly, an industry such as a healthcare management group can
sponsor channel that inserts wellness-related commercials and
health-related programs into a sponsored channel. A corporate or
public service entity can provide multiple language services to
receivers by directing receivers having selected radio identifiers
to insert content segments in a specified language into a selected
received program channel. Since the control data can be selectively
targeted to different receivers, the same broadcast program channel
can be simultaneously sponsored by two or more different entities.
As stated above, the indexed content segments can be transmitted as
part of the broadcast stream or sent via a different transport
link.
[0026] As will now be described in further detail with reference to
FIGS. 3-5, the receiver outputs a delayed stream 66 from the buffer
62 into which locally cached content has been substituted at
selected points in the received broadcast stream 58. Selected
segments in the buffered broadcast stream are dropped from playback
in view of the inserted locally cached content to ensure that the
buffer and corresponding playback stream delay does not grow
without management.
[0027] Reference is first made to FIG. 3 showing an illustrative
received content stream 58 having segments 1, 2, 3, 4 and 5, and
buffer 62 contents over a period of time (e.g., at intervals of
times t.sub.0, t.sub.1 and t.sub.2). In the exemplary embodiment,
the buffer 62 is preferably a circular buffer. At time to, the
buffer 62 is empty. At time t.sub.1, segments or tracks 1, 2 and a
portion of 3 have been received and buffered. At time t.sub.2,
segments 1 and 2 in the buffer have been written over by the
remainder of segment 3 and subsequent segments 4 and 5.
[0028] In FIG. 4, exemplary cached content segments (e.g.,
commercial segments) are shown as content segments A, B, C and D. A
received content stream having segments 1, 2, 3, 4 and 5, and
buffer 62 contents over a period of time (e.g., at intervals of
times t.sub.3, t.sub.4 and t.sub.5) are also shown. In accordance
with an exemplary embodiment of the present invention, the
broadcast waveform can include one or more bits to indicate whether
a particular track can be immediately followed by a commercial
segment insertion point. For example, track 1 can be formatted to
not allow being followed by a commercial in the playback stream 66.
Further, the receiver 50 can be controlled to detect or not detect
the next CPI, in which case segment 1 can again be prevented from
being followed by a commercial segment. When instructions to insert
a content segment B are received such as via a broadcast schedule
or via a content block in a particular channel of the received
broadcast stream, the receiver 50 is programmed to insert content
segment B after the next possible received segment, as indicated by
the playback pointer after program segment 2. As shown in the
playback stream 66, a content segment B commences playback at
t.sub.3, and the playback of the buffered segment 3 is delayed
until after the content segment B has been played back. After
content segment B is inserted and until the next receive content
stream insertion or deletion, all content in the playback stream is
played from within the buffer 62 and is delayed from the received
content stream 58.
[0029] FIG. 5 illustrates when a segment (e.g., segment 4) is
dropped from the buffer 62 in accordance with an advantageous
operation of the receiver 50 that overcomes the potential problem
of an infinitely growing buffer. As indicated in FIG. 5, the
receiver 50 is programmed to jump to the next playback pointer and
skip segments as needed. For example, the receiver 50 can be
programmed to insert commercial segments B and D within a selected
period (e.g., during lunch hour). After the delayed playback of
segment 3 from the buffer between times t.sub.4 and t.sub.5, the
receiver 50 inserts the next commercial segment D, as shown at time
t.sub.5. After the insertion of commercial segment D at time
t.sub.6, since a complete segment 4 has elapsed at this time, the
receiver 50 drops segment 4 from the playback stream 66 and resumes
delayed playback of segment 5 at time t.sub.6. In order for the
receiver to drop or skip one or more content segments, the content
segment is preferably fully contained within the buffer. This
insures the playback stream is resumed at the beginning of a new
content segment and avoids playback of fragmented content segments.
As stated above, the duration of a segment can be determined from
the PAD which facilitates the determination of whether to drop a
segment from the playback stream 66. Control bits in the PAD
instruct the receiver whether or not the respective content segment
may be removed from the stream.
[0030] The instructions to insert locally cached commercial content
into a received broadcast stream that are provided to a receiver
(i.e., via the broadcast stream or other source) are based on the
subscription service paid for by the user of that receiver. For
example, the receiver of a subscriber who that pays the premium
subscription fee is not configured to insert commercial content
into a received stream, but rather only receives whatever
commercial content that is provided on the broadcast channels.
Users, however, can opt to pay lower subscription rates for
corresponding tiers of service in accordance with the present
invention, For example, two different subscription rates (e.g.,
rate A at $6.00/month and rate B at $3.00 per month) that are lower
than the premium subscription rate can be offered. Receivers of
users paying rate A will be configured to insert 10 minutes of
commercial content per hour into a received broadcast stream during
playback, while receivers of users paying rate B will be configured
to insert 20 minutes of commercial content per hour into a received
broadcast stream during playback.
[0031] FIGS. 6, 7 and 8 will now be described with reference to
another aspect of an exemplary embodiment of the present invention
whereby content is inserted into a playback stream while channel
changes are occurring at the receiver 50. In FIG. 6, content
segment insertion and buffering is illustrated for a receiver that
is tuned at time t.sub.7 from channel 1 to channel 2, and tuned at
t.sub.8 back to channel 1. For contrast, FIG. 7 illustrates content
segment insertion and buffering in a receiver that is tuned at time
t.sub.7 from channel 1 to channel 2, but is not tuned back to
channel 1.
[0032] With continued reference to FIGS. 6 and 7, channel 1 is
represented as content stream #1, and channel 2 is represented as
content stream #2. The contents of plural buffers (e.g., buffer #1
and buffer #2) are illustrated at different points in time (i.e.,
t.sub.o and t.sub.6 through t.sub.9). The receiver 50 preferably
maintains dynamic buffers 62.sub.a, . . . , 62.sub.n for storing
content of the channel being played back and one or more other
buffers for respective channels recently selected for playback. The
buffers are preferably cleared when content from another channel is
being played back in the playback stream and can be used to begin
recording from the most recent or a different channel at later
point in time. In FIGS. 6 and 7, commercial segment B is inserted
for illustrative purposes, and the progress of a playback pointer
is illustrated using an arrow as shown. A playback stream 66 is
provided at the bottom of both FIGS. 6 and 7 to illustrate which
content (e.g., segments from content stream #1, segments from
content stream #2 or commercial segment B) is being played back at
different times (e.g., t.sub.o and t.sub.6 through t.sub.9).
[0033] As shown in FIG. 6, a receiver is initially tuned to content
stream #1. Buffer #1 commences recording content stream #1 at
t.sub.o for essentially live playback, that is, the playback steam
commences playback of the content segment 1-1 currently being
received via content stream #1. For illustrative purposes, the
receiver is scheduled to insert a commercial segment B at t.sub.6.
In other words, the receiver determines that it has been instructed
to insert the segment, and that segment 1-1 is indicated via
broadcast data or another source of information as not being
restricted from having commercial content inserted thereafter.
Accordingly, when the PAD data or other channel data source
indicates a track change (e.g., from segment 1-1 to segment 1-2) at
t.sub.6, the receiver inserts commercial segment B into the
playback stream at t.sub.6 while the buffer #1 continues to buffer
the currently tuned content stream #1.
[0034] At time t.sub.7 in FIG. 6, a channel change is made to
content stream #2. Buffer #2, which previously had been cleared,
commences recording the content segment 2-1 currently being
received on the selected content stream #2. In addition, the
playback stream switches from playback of the content segment B to
the content segment 2-1.
[0035] At time t8 in FIG. 6, a channel change is made from content
stream #2 back to content stream #1. Accordingly, the playback
stream returns to playing back content segment B which is finished
at t.sub.9. In other words, t.sub.6 plus the duration of the
content block B, t.sub.b, is equal to t.sub.9. Meanwhile, the
playback pointer for content stream #1 remains at the end of
content segment 1-1, and buffer #1 has commenced recording 1-2.
Thus, the playback stream commences playback of content segment 1-2
at t.sub.9 when the insertion of commercial segment B into the
playback stream is complete. Buffer #2 is cleared at t.sub.8 when
the receiver is tuned back to content stream #1. By maintaining
Buffer #1, instead of clearing it, while the receiver is tuned to
channel #2 insures subscribers will not be able to avert listening
to a commercial by changing the channel and returning to the
channel. When tuned to a channel, when the user changes the
channel, the existing channel buffer is maintained only if stored
content is actively being inserted or the playback content is
delayed with respect to the live stream due to previously inserted
content.
[0036] With reference now to FIG. 7, a receiver is initially tuned
to content stream #1. Buffer #1 commences recording content stream
#1 for essentially live playback, that is, the playback steam
commences playback of the content segment 1-1 currently being
received via content stream #1. For illustrative purposes, the
receiver is scheduled to insert a commercial segment B at t.sub.6.
Accordingly, when the PAD data or other channel data source
indicates a track change (e.g., from segment 1-1 to segment 1-2) at
t.sub.6, the receiver inserts commercial segment B into the
playback stream at t.sub.6 while the buffer #1 continues to buffer
the currently tuned content stream #1.
[0037] At time t.sub.7 in FIG. 6, a channel change is made to
content stream #2. Buffer #2, which previously had been cleared,
commences recording the content segment 2-1 currently being
received on the selected content stream #2. In addition, the
playback stream switches from playback of the content segment B to
the content segment 2-1.
[0038] Unlike FIG. 6, no channel change occurs at time t.sub.8.
Accordingly, the playback stream continues playing back content
stream #2 (segment 2-1 followed by segment 2-2, and so on until the
next channel change or instruction to insert a content segment into
received content stream #2. Meanwhile, buffer #1 is cleared at
t.sub.9 which is equal to t.sub.6 plus t.sub.b since the duration
of the inserted commercial segment to content stream #1 had already
elapsed without a channel change back to content stream #1. As
mentioned previously, buffer #1 would also have been maintained if
the channel were changed after the playback of content segment B,
since the playback stream would have been delayed at the time of
the channel change. In this case, Buffer #1 would be maintained for
a nominal period, such as 3 minutes, before being cleared. This is
to insure if a user is listening to a song with a playback delay
and briefly tunes to another channel and back, the playback content
would continue with the same relative delay as opposed to abruptly
changing the playback position by clearing the buffer and reverting
to the live content stream.
[0039] FIG. 8 illustrates a selected number of buffers indicated
generally at 62 that are dynamically maintained in accordance with
an aspect of the present invention and the content stream.
[0040] FIGS. 9 and 10 illustrate, respectively, two different
formats for control messages used to instruct a receiver as to when
to insert content, that is, a generic scheduled insertion method
and a generic stream ID insertion method. In FIG. 9, the control
message instructs a receiver to perform generic scheduled insertion
of segments (e.g., commercial segments) into a playback stream. For
example, a receiver can be instructed to insert selected segments
at least 4 times every hour. In FIG. 10, the control message
instructs a receiver to perform generic stream ID insertion of
segments (e.g., commercial segments) into a playback stream. For
example, a receiver can be instructed to insert selected segments
at selected points within a stream using a synchronous or
asynchronous method. For a synchronous method, a bit is set to
indicate a stream location specified using a Master Frame Count,
for example. For an asynchronous method, a change in PAD can be
used in the control message to specify a location in the stream for
inserting the segment.
[0041] With continued reference to FIG. 9, nSID is a Number (n) of
Service IDs (SID) in a message. SID1/T is First SID of n SIDs
active for this message and associated Tier (T). This control
message is acted upon by receivers which extract content from this
SID (e.g. tune to the channel). If receiver Tier exceeds SID/T
level, then this SID is not acted upon by the receiver. nMFC is a
Number (n) of Master Frame Counts (MFC) or set times in a message.
The MFC is an x-bit field in the header of each 432 mS SDARS TDM
frame which is set to 0 at 12 AM and incremented every frame
thereafter. This value can be used to derive the time of day. MFCW
is a Window (W) of Master Frame Counts (or Time) for which the MFC
is acted upon when tuning to the applicable SID. MFC1/T is a First
MFC of n MFCs to set the trigger for content insertion along with
the Tier. When the over-the-air MFC reaches the value of the MFC in
this message, the receiver pauses the live stream at the next
available content segment change and inserts the specified stored
content IDs. If the receiver Tier exceeds the MFC/T level, then
this MFC is not acted upon by the receiver. nS-CID is a Number (n)
of Stored Content IDs (S-CID) contained in this message. This
enables multiple CIDs to be inserted into the stream at the
available content segment change after the specified MFC. S-CID1/T
is a First S-CID of n S-CIDs to play from memory along with the
Tier. If the receiver Tier exceeds the S-CID/T level, then this
S-CID is not played by the receiver. The CID field preferably
points to a specific content block stored in memory. Optionally,
the CID field or ranges of values in the field could invoke a
function which includes radio specific parameters, such as
location, time of day, subscriber group, vehicle model, and so on,
in order to identify the content block or blocks in memory
appropriate for stream injection.
[0042] With continued reference to FIG. 10, nSID is a Number (n) of
Service IDs (SID) in message. SID1/T is a First SID of n SIDs
active for this message and associated Tier (T). This control
message is acted upon by receivers which extract content from this
SID (e.g. tune to the channel). If receiver Tier exceeds SID/T
level, then this SID is not acted upon by the receiver. SMFC is a
Start of Master Frame Count range for which this message is
applicable. The MFC is an x-bit field in the header of each 432 mS
SDARS TDM frame which is set to 0 at 12 AM and incremented every
frame thereafter. This value can be used to derive the time of day.
EMFC is an End of MFC range for which this message is applicable.
nB-CID is a Number (n) of Broadcast Content IDs contained in this
message. A B-CID is assigned to each content segment broadcast in
the live stream. B-CID1/T is a First B-CID of n B-CIDs to set the
trigger for content insertion along with the Tier. When the
over-the-air B-CID on the SID designated in this message matches
the B-CID in this message, the receiver pauses the live stream at
the end of the B-CID content segment and inserts the specified
Stored Content IDs (S-CIDs). If the receiver Tier exceeds the
B-CID/T level, then this B-CID is not acted upon by the receiver.
nS-CID is a Number (n) of Stored Content IDs (S-CID) contained in
this message. This enables multiple CIDs to be inserted into the
stream at the available content segment change after the specified
MFC. S-CID1/T is a First S-CID of n S-CIDs to play from memory
along with the respective Tier. If the receiver Tier exceeds the
S-CID/T level, then this S-CID is not played by the receiver.
[0043] It is to be understood that the present invention can also
be embodied as computer-readable codes on a computer-readable
recording medium. The computer-readable recording medium is any
data storage device that can store data which can thereafter be
read by a computer system. Examples of the computer-readable
recording medium include, but are not limited to, read-only memory
(ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy
disks, optical data storage devices, and carrier waves (such as
data transmission through the Internet via wired or wireless
transmission paths). The computer-readable recording medium can
also be distributed over network-coupled computer systems so that
the computer-readable code is stored and executed in a distributed
fashion. Also, functional programs, codes, and code segments for
accomplishing the present invention can be easily construed as
within the scope of the invention by programmers skilled in the art
to which the present invention pertains.
[0044] While the invention has been shown and described with
reference to a certain embodiment thereof, it will be understood by
those skilled in the art that various changes in form and details
may be made therein without departing from the spirit and scope of
the invention. Consequently, the scope of the invention should not
be limited to the embodiment, but should be defined by the appended
claims and equivalents thereof.
* * * * *