U.S. patent application number 15/277810 was filed with the patent office on 2018-03-29 for audio playback settings for voice interaction.
The applicant listed for this patent is Sonos, Inc.. Invention is credited to Klaus Hartung, Romi Kadri.
Application Number | 20180091913 15/277810 |
Document ID | / |
Family ID | 61685930 |
Filed Date | 2018-03-29 |
United States Patent
Application |
20180091913 |
Kind Code |
A1 |
Hartung; Klaus ; et
al. |
March 29, 2018 |
Audio Playback Settings for Voice Interaction
Abstract
Example techniques relate to voice interaction in an environment
with a media playback system that is playing back audio content. In
an example implementation, while playing back first audio in a
given environment at a given loudness: a playback device (a)
detects that an event is anticipated in the given environment, the
event involving playback of second audio and (b) determines a
loudness of background noise in the given environment, the
background noise comprising ambient noise in the given environment.
The playback device ducks the first audio in proportion to a
difference between the given loudness of the first audio and the
determined loudness of the background noise and plays back the
ducked first audio concurrently with the second audio.
Inventors: |
Hartung; Klaus; (Santa
Barbara, CA) ; Kadri; Romi; (Cambridge, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sonos, Inc. |
Santa Barbara |
CA |
US |
|
|
Family ID: |
61685930 |
Appl. No.: |
15/277810 |
Filed: |
September 27, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G10L 25/84 20130101;
H03G 3/32 20130101; H04R 2420/07 20130101; G10L 2015/088 20130101;
H04R 29/007 20130101; G06F 3/165 20130101; H03G 3/342 20130101;
G10L 15/22 20130101; H04R 2430/01 20130101; H04R 27/00 20130101;
H04R 2227/003 20130101; H04R 2227/005 20130101 |
International
Class: |
H04R 29/00 20060101
H04R029/00; G06F 3/16 20060101 G06F003/16; G10L 25/84 20060101
G10L025/84 |
Claims
1. A playback device comprising: a network interface; one or more
microphones; an audio stage comprising an amplifier; one or more
speakers; one or more processors; a housing, the housing carrying
at least the network interface, the one or more microphones, the
audio stage, the one or more speakers, the one or more processors,
and a computer-readable media having stored therein instructions
executable by the one or more processors to cause the playback
device to perform operations comprising: while playing back first
audio in a given environment at a given loudness via the audio
stage and the one or more speakers: (a) capturing, via the one or
more microphones, a voice input (b) determining that the captured
voice input includes audio data representing a wake word to invoke
a voice assistant service; (c) in response to determining that the
captured voice input includes audio data representing the wake word
to invoke the voice assistant service: (i) sending, via the network
interface to one or more servers of the voice assistant service,
the voice input and (ii) determining a loudness of background noise
in the given environment, wherein the background noise comprises
ambient noise in the given environment; (d) after determining the
loudness of background noise, receiving, via the network interface
from the one or more servers of the voice assistant service in
response to the voice input, second audio data representing a
spoken response to the voice input in response to receiving the
second audio data representing the spoken response to the voice
input, ducking the first audio in proportion to a difference
between the given loudness of the first audio and the determined
loudness of the background noise; and playing back the ducked first
audio concurrently with the second audio representing the spoken
response to the voice input via the audio stage and the one or more
speakers.
2. The playback device of claim 1, wherein playing back the ducked
first audio concurrently with the second audio comprises:
determining that a difference between a loudness of the ducked
first audio and a given dynamic range is (a) less than the
determined loudness of the background noise or (b) greater than the
determined loudness of the background noise; when the determined
difference between the loudness of the ducked first audio and the
given dynamic range is less than the determined loudness of the
background noise, compressing the first audio to a dynamic range
that is louder than the determined loudness of the background noise
and playing back the compressed first audio; and when the
determined difference between the loudness of the ducked first
audio and the given dynamic range is greater than the determined
loudness of the background noise, playing back the first audio
without compression.
3. (canceled)
4. (canceled)
5. (canceled)
6. The playback device of claim 1, wherein playing back the ducked
first audio concurrently with the second audio comprises: detecting
that a signal-to-noise ratio within the given environment is below
a voice input threshold; and responsively, filtering the first
audio, wherein filtering the first audio comprises cutting the
first audio in a frequency range corresponding to human speech.
7. The playback device of claim 6, wherein filtering the first
audio further comprises boosting the first audio outside the
frequency range corresponding to human speech.
8. The playback device of claim 1, wherein the playback device is a
first playback device of a group of playback device that includes
one or more second playback devices, and wherein playing back the
ducked first audio concurrently with the second audio comprises
playing back the ducked first audio concurrently with the second
audio in synchrony with the one or more second playback
devices.
9. The playback device of claim 1, wherein determining the loudness
of background noise in the given environment comprises measuring
the loudness of the background noise in the given environment via
one or more microphones.
10. The playback device of claim 9, wherein at least one of the one
or more microphones is housed in a networked microphone device that
is distinct from the playback device, and wherein measuring the
loudness of the background noise in the given environment via one
or more microphones comprises causing the networked microphone
device to measure the loudness of the background noise in the given
environment.
11. The playback device of claim 9, wherein measuring the loudness
of the background noise in the given environment comprises
offsetting the first audio being played back by the playback device
from the measurement of the background noise in the given
environment.
12. The playback device of claim 1, wherein the operations further
comprise detecting that the spoken response to the voice input has
been played back, and wherein ducking the first audio comprises
ducking the first audio until the spoken response to the voice
input has been played back.
13. A tangible, non-transitory computer-readable medium having
stored therein instructions executable by one or more processors to
cause a playback device to perform a method, the playback device
comprising a housing carrying at least a network interface, one or
more microphones, an audio stage, one or more speakers, and the one
or more processors, and the method comprising: while playing back
first audio in a given environment at a given loudness via the
audio stage and the one or more speakers: (a) capturing, via the
one or more microphones, a voice input; (b) determining that the
captured voice input includes audio data representing a wake word
to invoke a voice assistant service; (c) in response to determining
that the captured voice input includes audio data representing the
wake word to invoke the voice assistant service: (i) sending, via
the network interface to one or more servers of the voice assistant
service, the voice input and (ii) determining a loudness of
background noise in the given environment, wherein the background
noise comprises ambient noise in the given environment; (d) after
determining the loudness of background noise, receiving, via the
network interface from the one or more servers of the voice
assistant service in response to the voice input, second audio data
representing a spoken response to the voice input; in response to
receiving the second audio data representing the spoken response to
the voice input, ducking the first audio in proportion to a
difference between the given loudness of the first audio and the
determined loudness of the background noise; and playing back the
ducked first audio concurrently with the second audio representing
the spoken response to the voice input via the audio stage and the
one or more speakers.
14. The tangible, non-transitory computer-readable medium of claim
13, wherein playing back the ducked first audio concurrently with
the second audio comprises: determining that a difference between a
loudness of the ducked first audio and a given dynamic range is (a)
less than the determined loudness of the background noise or (b)
greater than the determined loudness of the background noise; when
the determined difference between the loudness of the ducked first
audio and the given dynamic range is less than the determined
loudness of the background noise, compressing the first audio to a
dynamic range that is louder than the determined loudness of the
background noise and playing back the compressed first audio; and
when the determined difference between the loudness of the ducked
first audio and the given dynamic range is greater than the
determined loudness of the background noise, playing back the first
audio without compression.
15. (canceled)
16. (canceled)
17. (canceled)
18. The tangible, non-transitory computer-readable medium of claim
13, wherein playing back the ducked first audio concurrently with
the second audio comprises: detecting that a signal-to-noise ratio
within the given environment is below a voice input threshold; and
in response to detecting that the signal-to-noise ratio within the
given environment is below the voice input threshold, filtering the
first audio, wherein filtering the first audio comprises cutting
the first audio in a frequency range corresponding to human
speech.
19. The tangible, non-transitory computer-readable medium of claim
1, wherein the operations further comprise detecting that the
spoken response to the voice input has been played back, and
wherein ducking the first audio comprises ducking the first audio
for a pre-determined period of time after the spoken response to
the voice input has been played back.
20. A method to be performed by a playback device comprising a
housing carrying at least a network interface, one or more
microphones, an audio stage, one or more speakers, the method
comprising: while playing back first audio in a given environment
at a given loudness via the audio stage and the one or more
speakers, the playback device: (a) capturing, via the one or more
microphones, a voice input; (b) determining that the captured voice
input includes audio data representing a wake word to invoke a
voice assistant service; (c) in response to determining that the
captured voice input includes audio data representing the wake word
to invoke the voice assistant service: (i) sending, via the network
interface to one or more servers of the voice assistant service,
the voice input and (ii) determining a loudness of background noise
in the given environment, wherein the background noise comprises
ambient noise in the given environment; (d) after determining the
loudness of background noise, receiving, via the network interface
from the one or more servers of the voice assistant service in
response to the voice input, second audio data representing a
spoken response to the voice input; in response to receiving the
second audio data representing the spoken response to the voice
input, the playback device ducking the first audio in proportion to
a difference between the given loudness of the first audio and the
determined loudness of the background noise; and the playback
device playing back the ducked first audio concurrently with the
second audio representing the spoken response to the voice input
via the audio stage and the one or more speakers.
21. The method of claim 20, wherein playing back the ducked first
audio concurrently with the second audio comprises: determining
that a difference between a loudness of the ducked first audio and
a given dynamic range is (a) less than the determined loudness of
the background noise or (b) greater than the determined loudness of
the background noise; when the determined difference between the
loudness of the ducked first audio and the given dynamic range is
less than the determined loudness of the background noise,
compressing the first audio to a dynamic range that is louder than
the determined loudness of the background noise and playing back
the compressed first audio; and when the determined difference
between the loudness of the ducked first audio and the given
dynamic range is greater than the determined loudness of the
background noise, playing back the first audio without
compression.
22. The method of claim 20, wherein playing back the ducked first
audio concurrently with the second audio comprises: detecting that
a signal-to-noise ratio within the given environment is below a
voice input threshold; and responsively, filtering the first audio,
wherein filtering the first audio comprises cutting the first audio
in a frequency range corresponding to human speech.
23. The method of claim 20, wherein filtering the first audio
further comprises boosting the first audio outside the frequency
range corresponding to human speech.
24. The tangible, non-transitory computer-readable medium of claim
13, wherein playing back the ducked first audio concurrently with
the second audio comprises: detecting that a signal-to-noise ratio
within the given environment is below a voice input threshold; and
responsively, filtering the first audio, wherein filtering the
first audio comprises cutting the first audio in a frequency range
corresponding to human speech.
25. The tangible, non-transitory computer-readable medium of claim
13, wherein filtering the first audio further comprises boosting
the first audio outside the frequency range corresponding to human
speech.
26. The tangible, non-transitory computer-readable medium of claim
13, wherein the operations further comprise detecting that the
spoken response to the voice input has been played back, and
wherein ducking the first audio comprises ducking the first audio
until the spoken response to the voice input has been played back.
Description
FIELD OF THE DISCLOSURE
[0001] The disclosure is related to consumer goods and, more
particularly, to methods, systems, products, features, services,
and other elements directed to media playback or some aspect
thereof.
BACKGROUND
[0002] Options for accessing and listening to digital audio in an
out-loud setting were limited until in 2003, when SONOS, Inc. filed
for one of its first patent applications, entitled "Method for
Synchronizing Audio Playback between Multiple Networked Devices,"
and began offering a media playback system for sale in 2005. The
Sonos Wireless HiFi System enables people to experience music from
many sources via one or more networked playback devices. Through a
software control application installed on a smartphone, tablet, or
computer, one can play what he or she wants in any room that has a
networked playback device. Additionally, using the controller, for
example, different songs can be streamed to each room with a
playback device, rooms can be grouped together for synchronous
playback, or the same song can be heard in all rooms
synchronously.
[0003] Given the ever growing interest in digital media, there
continues to be a need to develop consumer-accessible technologies
to further enhance the listening experience.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Features, aspects, and advantages of the presently disclosed
technology may be better understood with regard to the following
description, appended claims, and accompanying drawings where:
[0005] FIG. 1 shows an example media playback system configuration
in which certain embodiments may be practiced;
[0006] FIG. 2 shows a functional block diagram of an example
playback device;
[0007] FIG. 3 shows a functional block diagram of an example
control device;
[0008] FIG. 4 shows an example controller interface;
[0009] FIG. 5 shows an example plurality of network devices;
[0010] FIG. 6 shows a functional block diagram of an example
network microphone device;
[0011] FIG. 7 shows a technique to duck audio, according to example
implementations;
[0012] FIG. 8 shows a chart illustrating ducking of audio
content;
[0013] FIG. 9 shows a technique to compress audio, according to
example implementations;
[0014] FIG. 10 is a diagram illustrating ducking and compression of
audio content; and
[0015] FIG. 11 shows a technique to equalize audio, according to
example implementations.
[0016] The drawings are for the purpose of illustrating example
embodiments, but it is understood that the inventions are not
limited to the arrangements and instrumentality shown in the
drawings.
DETAILED DESCRIPTION
I. OVERVIEW
[0017] Ambient noise may interfere with conversation between
people. For instance, two people engaged in conversation in a
crowded room may have difficulty understanding one another over
ambient noise from other people in the room as well as other
sources of sound (e.g., music or other audio content from an audio
playback system). When spoken words are clearly audible over
ambient noise, those spoken words can be considered to have a
"good" signal-to-noise ratio (i.e., "good" enough for comprehension
during a conversation).
[0018] Some voice services (e.g., Amazon.RTM. ALEXA.RTM.,
Microsoft.RTM. CORTANA.RTM., and Apple.RTM. SIRI.RTM., among others
now commercially available or that become available in the future)
may use spoken words as input for voice control, search, and other
operations. A networked microphone device (e.g., a wireless
speaker, a smartphone, tablet, laptop computer, or other device)
may include a microphone for detecting voice inputs and a network
interface for querying a voice service with the voice input. The
voice response may respond to the query with a response, which
might be a spoken response played aloud by the networked microphone
device via one or more speakers. As with conversations between two
people, a relatively high signal-to-noise ratio may facilitate a
voice service comprehending a voice input (i.e., being able to
effectively parse the spoken words of the voice input into a
command) and also a user comprehending a spoken response from a
voice service over noise.
[0019] As noted above, various sources of sound may be considered
noise relative to the voice input. For instance, when music is
being played in a given environment while a voice input is spoken
in that same environment, the music can be considered "noise" with
respect to the voice input. Other sources of sound may generate
ambient (e.g., background) noise while the voice input is spoken.
Improving the signal-to-noise ratio of the voice input relative to
these different sources of noise may improve comprehension of the
voice input.
[0020] Improving the voice input-to-noise ratio may involve
increasing the volume of the voice input or decreasing the volume
of the noise, such that the volume of the voice input relative to
the noise is increased. The human voice typically covers a broad
frequency spectrum. However, only relatively narrow frequency bands
are necessary to understand speech. The relatively narrow frequency
bands include the fundamental frequencies (approximately 100 Hz for
males and 180 Hz for females) and the frequencies just above.
Therefore, a "good" voice input-to-noise ratio within those
relatively narrow frequency bands is often sufficient for
comprehension. This ratio does not necessarily need to be "good"
across a broad frequency spectrum for the voice input to be
comprehendible. These relatively narrow frequency bands can be
referred to a speech bands.
[0021] Like the human voice, music typically covers a broad
frequency spectrum. However, the relatively narrow frequency bands
that drive speech comprehension are not as important to music
consumption. Rhythm, timbre, and other compositional factors of
music can be preserved when frequencies within the music that
correspond to the speech bands are cut. As such, when music is
being played while a voice input is spoken or a spoken response is
played back, frequencies of the music corresponding to the speech
bands can be ducked (i.e., temporality reduced in volume) to
improve the relative volume of the voice input or spoken response
within the speech bands to the music. This ducking may improve the
signal-to-noise ratio without significantly compromising the music
playback (the "noise").
[0022] One possible drawback to lowering the volume of the music
within certain frequency ranges is that the perceived loudness of
the music as a whole is reduced. However, an audio playback system
may offset this reduction in perceived loudness by increasing the
volume in other frequency bands (e.g., in all other frequencies
outside the speech bands) while the volume of the music in the
speech bands is being cut.
[0023] Another possible drawback to lowering the volume of the
music within certain frequency ranges is that some of the
lower-amplitude (relatively quiet) detail in the music may drop
below the noise floor (e.g., the ambient noise). Similar to how
speech can be difficult to understand over music and ambient noise,
portions of the music might be difficult to understand over the
noise floor (e.g., conversations between people, appliances, HVAC,
outdoor noise such as traffic, among other possible sources).
Losing low-amplitude fine detail in the music below the noise floor
may impact enjoyment of the music.
[0024] In some implementations, the audio playback system may
compress the music to bring the low-amplitude fine detail above the
noise floor. The audio playback system may measure the ambient
noise level, which relative to the music might include human
speech. Then, the music may be compressed to increase the level of
the low-amplitude fine detail above the noise floor. While
compression might not preserve all detail, compressing the music
may preserve some low-amplitude fine detail that would have been
otherwise inaudible over the noise floor.
[0025] As noted above, speech may be difficult to comprehend in the
presence of noise (e.g., music playback or other ambient noise). As
such, some example techniques noted above may involve an audio
playback system ducking music or other audio content to improve the
signal-to-noise ratio of speech (e.g., voice inputs and spoken
responses) relative to this noise, which may render the speech more
comprehendible. More generally, music playback within an
environment may make speech by two or more people attempting a
conversation difficult to understand. In an attempt to alleviate
this issue, an audio playback system may apply an equalization that
improves the signal-to-noise (i.e., speech-to-music) ratio. This
equalization may cut frequencies of music within the speech bands
(i.e., the fundamental frequencies and those slightly above). The
equalization may also boost frequencies outside the speech bands in
an attempt to maintain the perceived loudness of the music when
portions of the music within the speech bands are cut.
[0026] Since such an equalization changes the characteristics of
the music being played back, some users may prefer that this
equalization is not always applied. Rather, such users might prefer
that the equalization is applied when speech is present. Speech
within a given environment might include a conversation between two
people in the environment, a telephone conversation between one
person in the environment and other person somewhere else, speech
from a voice-capable artificial intelligence (e.g. a spoken
response from a voice service), among other examples. In some
implementation, an audio playback system may include one or more
microphones to detect speech. Alternatively, the audio playback
system may use sensors to detect the number of people within the
environment, which may indirectly indicate the presence of speech
(i.e., the system may assume that the volume of speech within an
environment increases with the number of possible speakers within
that environment). When speech is detected, the audio playback
system may apply the equalization to improve the signal-to-noise
ratio of the speech to noise.
[0027] Example techniques may involve improving signal-to-noise
ratio of speech to noise, such as music. A first implementation may
include a playback device playing back first audio in a given
environment at a given loudness, and while playing back the first
audio: (a) detecting that an event is anticipated in the given
environment, the event involving playback of second audio and (b)
determining a loudness of background noise in the given
environment, wherein the background noise comprises ambient noise
in the given environment. The first implementation may further
include ducking the first audio in proportion to a difference
between the given loudness of the first audio and the determined
loudness of the background noise. The first implementation may also
include playing back the ducked first audio concurrently with the
second audio.
[0028] A second implementation may include a playback device
determining a loudness of first audio being played back by the
playback device and a loudness of background noise in a given
environment. The second implementation may also include determining
whether a difference between a loudness of the first audio and a
given dynamic range is (a) less than a determined loudness of the
background noise or (b) greater than the determined loudness of the
background noise. When the determined difference between the
loudness of the ducked first audio and the given dynamic range is
less than the determined loudness of the background noise, the
second implementation may further include compressing the first
audio to a dynamic range that is louder than the determined
loudness of the background noise and playing back the compressed
first audio. When the determined difference between the loudness of
the first audio and the given dynamic range is greater than the
determined loudness of the background noise, the second
implementation may include playing back the first audio without
compression.
[0029] A third implementation may involve a playback device playing
audio content. While playing audio, the playback device may detect
that a signal-to-noise ratio in the given environment is below a
speech threshold. While the signal-to-noise ratio in the given
environment is below a speech threshold, the playback device may
apply an equalization to the audio content. The equalization may
cut certain frequency bands corresponding to human speech. The
equalization may also boost other frequency bands not corresponding
to human speech.
[0030] Each of the these example implementations may be embodied as
a method, a device configured to carry out the implementation, a
system of devices configured to carry out the implementation, or a
non-transitory computer-readable medium containing instructions
that are executable by one or more processors to carry out the
implementation, among other examples. It will be understood by one
of ordinary skill in the art that this disclosure includes numerous
other embodiments, including combinations of the example features
described herein. Further, any example operation described as being
performed by a given device to illustrate a technique may be
performed by any suitable devices, including the devices described
herein. Yet further, any device may cause another device to perform
any of the operations described herein.
[0031] While some examples described herein may refer to functions
performed by given actors such as "users" and/or other entities, it
should be understood that this description is for purposes of
explanation only. The claims should not be interpreted to require
action by any such example actor unless explicitly required by the
language of the claims themselves.
II. EXAMPLE OPERATING ENVIRONMENT
[0032] FIG. 1 illustrates an example configuration of a media
playback system 100 in which one or more embodiments disclosed
herein may be practiced or implemented. The media playback system
100 as shown is associated with an example home environment having
several rooms and spaces, such as for example, a master bedroom, an
office, a dining room, and a living room. As shown in the example
of FIG. 1, the media playback system 100 includes playback devices
102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, control
devices 126 and 128, a wired or wireless network router 130, and a
networked microphone device 132.
[0033] Further discussions relating to the different components of
the example media playback system 100 and how the different
components may interact to provide a user with a media experience
may be found in the following sections. While discussions herein
may generally refer to the example media playback system 100,
technologies described herein are not limited to applications
within, among other things, the home environment as shown in FIG.
1. For instance, the technologies described herein may be useful in
environments where multi-zone audio may be desired, such as, for
example, a commercial setting like a restaurant, mall or airport, a
vehicle like a sports utility vehicle (SUV), bus or car, a ship or
boat, an airplane, and so on.
a. Example Playback Devices
[0034] FIG. 2 shows a functional block diagram of an example
playback device 200 that may be configured to be one or more of the
playback devices 102-124 of the media playback system 100 of FIG.
1. The playback device 200 may include a processor 202, software
components 204, memory 206, audio processing components 208, audio
amplifier(s) 210, speaker(s) 212, and a network interface 214
including wireless interface(s) 216 and wired interface(s) 218. In
one case, the playback device 200 may not include the speaker(s)
212, but rather a speaker interface for connecting the playback
device 200 to external speakers. In another case, the playback
device 200 may include neither the speaker(s) 212 nor the audio
amplifier(s) 210, but rather an audio interface for connecting the
playback device 200 to an external audio amplifier or audio-visual
receiver.
[0035] In one example, the processor 202 may be a clock-driven
computing component configured to process input data according to
instructions stored in the memory 206. The memory 206 may be a
tangible computer-readable medium configured to store instructions
executable by the processor 202. For instance, the memory 206 may
be data storage that can be loaded with one or more of the software
components 204 executable by the processor 202 to achieve certain
functions. In one example, the functions may involve the playback
device 200 retrieving audio data from an audio source or another
playback device. In another example, the functions may involve the
playback device 200 sending audio data to another device or
playback device on a network. In yet another example, the functions
may involve pairing of the playback device 200 with one or more
playback devices to create a multi-channel audio environment.
[0036] Certain functions may involve the playback device 200
synchronizing playback of audio content with one or more other
playback devices. During synchronous playback, a listener will
preferably not be able to perceive time-delay differences between
playback of the audio content by the playback device 200 and the
one or more other playback devices. U.S. Pat. No. 8,234,395
entitled, "System and method for synchronizing operations among a
plurality of independently clocked digital data processing
devices," which is hereby incorporated by reference, provides in
more detail some examples for audio playback synchronization among
playback devices.
[0037] The memory 206 may further be configured to store data
associated with the playback device 200, such as one or more zones
and/or zone groups the playback device 200 is a part of, audio
sources accessible by the playback device 200, or a playback queue
that the playback device 200 (or some other playback device) may be
associated with. The data may be stored as one or more state
variables that are periodically updated and used to describe the
state of the playback device 200. The memory 206 may also include
the data associated with the state of the other devices of the
media system, and shared from time to time among the devices so
that one or more of the devices have the most recent data
associated with the system. Other embodiments are also
possible.
[0038] The audio processing components 208 may include one or more
digital-to-analog converters (DAC), an audio preprocessing
component, an audio enhancement component or a digital signal
processor (DSP), and so on. In one embodiment, one or more of the
audio processing components 208 may be a subcomponent of the
processor 202. In one example, audio content may be processed
and/or intentionally altered by the audio processing components 208
to produce audio signals. The produced audio signals may then be
provided to the audio amplifier(s) 210 for amplification and
playback through speaker(s) 212. Particularly, the audio
amplifier(s) 210 may include devices configured to amplify audio
signals to a level for driving one or more of the speakers 212. The
speaker(s) 212 may include an individual transducer (e.g., a
"driver") or a complete speaker system involving an enclosure with
one or more drivers. A particular driver of the speaker(s) 212 may
include, for example, a subwoofer (e.g., for low frequencies), a
mid-range driver (e.g., for middle frequencies), and/or a tweeter
(e.g., for high frequencies). In some cases, each transducer in the
one or more speakers 212 may be driven by an individual
corresponding audio amplifier of the audio amplifier(s) 210. In
addition to producing analog signals for playback by the playback
device 200, the audio processing components 208 may be configured
to process audio content to be sent to one or more other playback
devices for playback.
[0039] Audio content to be processed and/or played back by the
playback device 200 may be received from an external source, such
as via an audio line-in input connection (e.g., an auto-detecting
3.5 mm audio line-in connection) or the network interface 214.
[0040] The network interface 214 may be configured to facilitate a
data flow between the playback device 200 and one or more other
devices on a data network. As such, the playback device 200 may be
configured to receive audio content over the data network from one
or more other playback devices in communication with the playback
device 200, network devices within a local area network, or audio
content sources over a wide area network such as the Internet. In
one example, the audio content and other signals transmitted and
received by the playback device 200 may be transmitted in the form
of digital packet data containing an Internet Protocol (IP)-based
source address and IP-based destination addresses. In such a case,
the network interface 214 may be configured to parse the digital
packet data such that the data destined for the playback device 200
is properly received and processed by the playback device 200.
[0041] As shown, the network interface 214 may include wireless
interface(s) 216 and wired interface(s) 218. The wireless
interface(s) 216 may provide network interface functions for the
playback device 200 to wirelessly communicate with other devices
(e.g., other playback device(s), speaker(s), receiver(s), network
device(s), control device(s) within a data network the playback
device 200 is associated with) in accordance with a communication
protocol (e.g., any wireless standard including IEEE 802.11a,
802.11b, 802.11g, 802.11n, 802.11ac, 802.15, 4G mobile
communication standard, and so on). The wired interface(s) 218 may
provide network interface functions for the playback device 200 to
communicate over a wired connection with other devices in
accordance with a communication protocol (e.g., IEEE 802.3). While
the network interface 214 shown in FIG. 2 includes both wireless
interface(s) 216 and wired interface(s) 218, the network interface
214 may in some embodiments include only wireless interface(s) or
only wired interface(s).
[0042] In one example, the playback device 200 and one other
playback device may be paired to play two separate audio components
of audio content. For instance, playback device 200 may be
configured to play a left channel audio component, while the other
playback device may be configured to play a right channel audio
component, thereby producing or enhancing a stereo effect of the
audio content. The paired playback devices (also referred to as
"bonded playback devices") may further play audio content in
synchrony with other playback devices.
[0043] In another example, the playback device 200 may be sonically
consolidated with one or more other playback devices to form a
single, consolidated playback device. A consolidated playback
device may be configured to process and reproduce sound differently
than an unconsolidated playback device or playback devices that are
paired, because a consolidated playback device may have additional
speaker drivers through which audio content may be rendered. For
instance, if the playback device 200 is a playback device designed
to render low frequency range audio content (i.e. a subwoofer), the
playback device 200 may be consolidated with a playback device
designed to render full frequency range audio content. In such a
case, the full frequency range playback device, when consolidated
with the low frequency playback device 200, may be configured to
render only the mid and high frequency components of audio content,
while the low frequency range playback device 200 renders the low
frequency component of the audio content. The consolidated playback
device may further be paired with a single playback device or yet
another consolidated playback device.
[0044] By way of illustration, SONOS, Inc. presently offers (or has
offered) for sale certain playback devices including a "PLAY:1,"
"PLAY:3," "PLAY:5," "PLAYBAR," "CONNECT:AMP," "CONNECT," and "SUB."
Any other past, present, and/or future playback devices may
additionally or alternatively be used to implement the playback
devices of example embodiments disclosed herein. Additionally, it
is understood that a playback device is not limited to the example
illustrated in FIG. 2 or to the SONOS product offerings. For
example, a playback device may include a wired or wireless
headphone. In another example, a playback device may include or
interact with a docking station for personal mobile media playback
devices. In yet another example, a playback device may be integral
to another device or component such as a television, a lighting
fixture, or some other device for indoor or outdoor use.
b. Example Playback Zone Configurations
[0045] Referring back to the media playback system 100 of FIG. 1,
the environment may have one or more playback zones, each with one
or more playback devices. The media playback system 100 may be
established with one or more playback zones, after which one or
more zones may be added, or removed to arrive at the example
configuration shown in FIG. 1. Each zone may be given a name
according to a different room or space such as an office, bathroom,
master bedroom, bedroom, kitchen, dining room, living room, and/or
balcony. In one case, a single playback zone may include multiple
rooms or spaces. In another case, a single room or space may
include multiple playback zones.
[0046] As shown in FIG. 1, the balcony, dining room, kitchen,
bathroom, office, and bedroom zones each have one playback device,
while the living room and master bedroom zones each have multiple
playback devices. In the living room zone, playback devices 104,
106, 108, and 110 may be configured to play audio content in
synchrony as individual playback devices, as one or more bonded
playback devices, as one or more consolidated playback devices, or
any combination thereof. Similarly, in the case of the master
bedroom, playback devices 122 and 124 may be configured to play
audio content in synchrony as individual playback devices, as a
bonded playback device, or as a consolidated playback device.
[0047] In one example, one or more playback zones in the
environment of FIG. 1 may each be playing different audio content.
For instance, the user may be grilling in the balcony zone and
listening to hip hop music being played by the playback device 102
while another user may be preparing food in the kitchen zone and
listening to classical music being played by the playback device
114. In another example, a playback zone may play the same audio
content in synchrony with another playback zone. For instance, the
user may be in the office zone where the playback device 118 is
playing the same rock music that is being playing by playback
device 102 in the balcony zone. In such a case, playback devices
102 and 118 may be playing the rock music in synchrony such that
the user may seamlessly (or at least substantially seamlessly)
enjoy the audio content that is being played out-loud while moving
between different playback zones. Synchronization among playback
zones may be achieved in a manner similar to that of
synchronization among playback devices, as described in previously
referenced U.S. Pat. No. 8,234,395.
[0048] As suggested above, the zone configurations of the media
playback system 100 may be dynamically modified, and in some
embodiments, the media playback system 100 supports numerous
configurations. For instance, if a user physically moves one or
more playback devices to or from a zone, the media playback system
100 may be reconfigured to accommodate the change(s). For instance,
if the user physically moves the playback device 102 from the
balcony zone to the office zone, the office zone may now include
both the playback device 118 and the playback device 102. The
playback device 102 may be paired or grouped with the office zone
and/or renamed if so desired via a control device such as the
control devices 126 and 128. On the other hand, if the one or more
playback devices are moved to a particular area in the home
environment that is not already a playback zone, a new playback
zone may be created for the particular area.
[0049] Further, different playback zones of the media playback
system 100 may be dynamically combined into zone groups or split up
into individual playback zones. For instance, the dining room zone
and the kitchen zone 114 may be combined into a zone group for a
dinner party such that playback devices 112 and 114 may render
audio content in synchrony. On the other hand, the living room zone
may be split into a television zone including playback device 104,
and a listening zone including playback devices 106, 108, and 110,
if the user wishes to listen to music in the living room space
while another user wishes to watch television.
c. Example Control Devices
[0050] FIG. 3 shows a functional block diagram of an example
control device 300 that may be configured to be one or both of the
control devices 126 and 128 of the media playback system 100.
Control device 300 may also be referred to as a controller 300. As
shown, the control device 300 may include a processor 302, memory
304, a network interface 306, and a user interface 308. In one
example, the control device 300 may be a dedicated controller for
the media playback system 100. In another example, the control
device 300 may be a network device on which media playback system
controller application software may be installed, such as for
example, an iPhone.TM. iPad.TM. or any other smart phone, tablet or
network device (e.g., a networked computer such as a PC or
Mac.TM.)
[0051] The processor 302 may be configured to perform functions
relevant to facilitating user access, control, and configuration of
the media playback system 100. The memory 304 may be configured to
store instructions executable by the processor 302 to perform those
functions. The memory 304 may also be configured to store the media
playback system controller application software and other data
associated with the media playback system 100 and the user.
[0052] In one example, the network interface 306 may be based on an
industry standard (e.g., infrared, radio, wired standards including
IEEE 802.3, wireless standards including IEEE 802.11a, 802.11b,
802.11g, 802.11n, 802.11ac, 802.15, 4G mobile communication
standard, and so on). The network interface 306 may provide a means
for the control device 300 to communicate with other devices in the
media playback system 100. In one example, data and information
(e.g., such as a state variable) may be communicated between
control device 300 and other devices via the network interface 306.
For instance, playback zone and zone group configurations in the
media playback system 100 may be received by the control device 300
from a playback device or another network device, or transmitted by
the control device 300 to another playback device or network device
via the network interface 306. In some cases, the other network
device may be another control device.
[0053] Playback device control commands such as volume control and
audio playback control may also be communicated from the control
device 300 to a playback device via the network interface 306. As
suggested above, changes to configurations of the media playback
system 100 may also be performed by a user using the control device
300. The configuration changes may include adding/removing one or
more playback devices to/from a zone, adding/removing one or more
zones to/from a zone group, forming a bonded or consolidated
player, separating one or more playback devices from a bonded or
consolidated player, among others. Accordingly, the control device
300 may sometimes be referred to as a controller, whether the
control device 300 is a dedicated controller or a network device on
which media playback system controller application software is
installed.
[0054] The user interface 308 of the control device 300 may be
configured to facilitate user access and control of the media
playback system 100, by providing a controller interface such as
the controller interface 400 shown in FIG. 4. The controller
interface 400 includes a playback control region 410, a playback
zone region 420, a playback status region 430, a playback queue
region 440, and an audio content sources region 450. The user
interface 400 as shown is just one example of a user interface that
may be provided on a network device such as the control device 300
of FIG. 3 (and/or the control devices 126 and 128 of FIG. 1) and
accessed by users to control a media playback system such as the
media playback system 100. Other user interfaces of varying
formats, styles, and interactive sequences may alternatively be
implemented on one or more network devices to provide comparable
control access to a media playback system.
[0055] The playback control region 410 may include selectable
(e.g., by way of touch or by using a cursor) icons to cause
playback devices in a selected playback zone or zone group to play
or pause, fast forward, rewind, skip to next, skip to previous,
enter/exit shuffle mode, enter/exit repeat mode, enter/exit cross
fade mode. The playback control region 410 may also include
selectable icons to modify equalization settings, and playback
volume, among other possibilities.
[0056] The playback zone region 420 may include representations of
playback zones within the media playback system 100. In some
embodiments, the graphical representations of playback zones may be
selectable to bring up additional selectable icons to manage or
configure the playback zones in the media playback system, such as
a creation of bonded zones, creation of zone groups, separation of
zone groups, and renaming of zone groups, among other
possibilities.
[0057] For example, as shown, a "group" icon may be provided within
each of the graphical representations of playback zones. The
"group" icon provided within a graphical representation of a
particular zone may be selectable to bring up options to select one
or more other zones in the media playback system to be grouped with
the particular zone. Once grouped, playback devices in the zones
that have been grouped with the particular zone will be configured
to play audio content in synchrony with the playback device(s) in
the particular zone. Analogously, a "group" icon may be provided
within a graphical representation of a zone group. In this case,
the "group" icon may be selectable to bring up options to deselect
one or more zones in the zone group to be removed from the zone
group. Other interactions and implementations for grouping and
ungrouping zones via a user interface such as the user interface
400 are also possible. The representations of playback zones in the
playback zone region 420 may be dynamically updated as playback
zone or zone group configurations are modified.
[0058] The playback status region 430 may include graphical
representations of audio content that is presently being played,
previously played, or scheduled to play next in the selected
playback zone or zone group. The selected playback zone or zone
group may be visually distinguished on the user interface, such as
within the playback zone region 420 and/or the playback status
region 430. The graphical representations may include track title,
artist name, album name, album year, track length, and other
relevant information that may be useful for the user to know when
controlling the media playback system via the user interface
400.
[0059] The playback queue region 440 may include graphical
representations of audio content in a playback queue associated
with the selected playback zone or zone group. In some embodiments,
each playback zone or zone group may be associated with a playback
queue containing information corresponding to zero or more audio
items for playback by the playback zone or zone group. For
instance, each audio item in the playback queue may comprise a
uniform resource identifier (URI), a uniform resource locator (URL)
or some other identifier that may be used by a playback device in
the playback zone or zone group to find and/or retrieve the audio
item from a local audio content source or a networked audio content
source, possibly for playback by the playback device.
[0060] In one example, a playlist may be added to a playback queue,
in which case information corresponding to each audio item in the
playlist may be added to the playback queue. In another example,
audio items in a playback queue may be saved as a playlist. In a
further example, a playback queue may be empty, or populated but
"not in use" when the playback zone or zone group is playing
continuously streaming audio content, such as Internet radio that
may continue to play until otherwise stopped, rather than discrete
audio items that have playback durations. In an alternative
embodiment, a playback queue can include Internet radio and/or
other streaming audio content items and be "in use" when the
playback zone or zone group is playing those items. Other examples
are also possible.
[0061] When playback zones or zone groups are "grouped" or
"ungrouped," playback queues associated with the affected playback
zones or zone groups may be cleared or re-associated. For example,
if a first playback zone including a first playback queue is
grouped with a second playback zone including a second playback
queue, the established zone group may have an associated playback
queue that is initially empty, that contains audio items from the
first playback queue (such as if the second playback zone was added
to the first playback zone), that contains audio items from the
second playback queue (such as if the first playback zone was added
to the second playback zone), or a combination of audio items from
both the first and second playback queues. Subsequently, if the
established zone group is ungrouped, the resulting first playback
zone may be re-associated with the previous first playback queue,
or be associated with a new playback queue that is empty or
contains audio items from the playback queue associated with the
established zone group before the established zone group was
ungrouped. Similarly, the resulting second playback zone may be
re-associated with the previous second playback queue, or be
associated with a new playback queue that is empty, or contains
audio items from the playback queue associated with the established
zone group before the established zone group was ungrouped. Other
examples are also possible.
[0062] Referring back to the user interface 400 of FIG. 4, the
graphical representations of audio content in the playback queue
region 440 may include track titles, artist names, track lengths,
and other relevant information associated with the audio content in
the playback queue. In one example, graphical representations of
audio content may be selectable to bring up additional selectable
icons to manage and/or manipulate the playback queue and/or audio
content represented in the playback queue. For instance, a
represented audio content may be removed from the playback queue,
moved to a different position within the playback queue, or
selected to be played immediately, or after any currently playing
audio content, among other possibilities. A playback queue
associated with a playback zone or zone group may be stored in a
memory on one or more playback devices in the playback zone or zone
group, on a playback device that is not in the playback zone or
zone group, and/or some other designated device. Playback of such a
playback queue may involve one or more playback devices playing
back media items of the queue, perhaps in sequential or random
order.
[0063] The audio content sources region 450 may include graphical
representations of selectable audio content sources from which
audio content may be retrieved and played by the selected playback
zone or zone group. Discussions pertaining to audio content sources
may be found in the following section.
d. Example Audio Content Sources
[0064] As indicated previously, one or more playback devices in a
zone or zone group may be configured to retrieve for playback audio
content (e.g., according to a corresponding URI or URL for the
audio content) from a variety of available audio content sources.
In one example, audio content may be retrieved by a playback device
directly from a corresponding audio content source (e.g., a line-in
connection). In another example, audio content may be provided to a
playback device over a network via one or more other playback
devices or network devices.
[0065] Example audio content sources may include a memory of one or
more playback devices in a media playback system such as the media
playback system 100 of FIG. 1, local music libraries on one or more
network devices (such as a control device, a network-enabled
personal computer, or a networked-attached storage (NAS), for
example), streaming audio services providing audio content via the
Internet (e.g., the cloud), or audio sources connected to the media
playback system via a line-in input connection on a playback device
or network devise, among other possibilities.
[0066] In some embodiments, audio content sources may be regularly
added or removed from a media playback system such as the media
playback system 100 of FIG. 1. In one example, an indexing of audio
items may be performed whenever one or more audio content sources
are added, removed or updated. Indexing of audio items may involve
scanning for identifiable audio items in all folders/directory
shared over a network accessible by playback devices in the media
playback system, and generating or updating an audio content
database containing metadata (e.g., title, artist, album, track
length, among others) and other associated information, such as a
URI or URL for each identifiable audio item found. Other examples
for managing and maintaining audio content sources may also be
possible.
e. Example Plurality of Networked Devices
[0067] FIG. 5 shows an example plurality of devices 500 that may be
configured to provide an audio playback experience based on voice
control. One having ordinary skill in the art will appreciate that
the devices shown in FIG. 5 are for illustrative purposes only, and
variations including different and/or additional devices may be
possible. As shown, the plurality of devices 500 includes computing
devices 504, 506, and 508; network microphone devices (NMDs) 512,
514, and 516; playback devices (PBDs) 532, 534, 536, and 538; and a
controller device (CR) 522.
[0068] Each of the plurality of devices 500 may be network-capable
devices that can establish communication with one or more other
devices in the plurality of devices according to one or more
network protocols, such as NFC, Bluetooth, Ethernet, and IEEE
802.11, among other examples, over one or more types of networks,
such as wide area networks (WAN), local area networks (LAN), and
personal area networks (PAN), among other possibilities.
[0069] As shown, the computing devices 504, 506, and 508 may be
part of a cloud network 502. The cloud network 502 may include
additional computing devices. In one example, the computing devices
504, 506, and 508 may be different servers. In another example, two
or more of the computing devices 504, 506, and 508 may be modules
of a single server. Analogously, each of the computing device 504,
506, and 508 may include one or more modules or servers. For ease
of illustration purposes herein, each of the computing devices 504,
506, and 508 may be configured to perform particular functions
within the cloud network 502. For instance, computing device 508
may be a source of audio content for a streaming music service.
[0070] As shown, the computing device 504 may be configured to
interface with NMDs 512, 514, and 516 via communication path 542.
NMDs 512, 514, and 516 may be components of one or more "Smart
Home" systems. In one case, NMDs 512, 514, and 516 may be
physically distributed throughout a household, similar to the
distribution of devices shown in FIG. 1. In another case, two or
more of the NMDs 512, 514, and 516 may be physically positioned
within relative close proximity of one another. Communication path
542 may comprise one or more types of networks, such as a WAN
including the Internet, LAN, and/or PAN, among other
possibilities.
[0071] In one example, one or more of the NMDs 512, 514, and 516
may be devices configured primarily for audio detection. In another
example, one or more of the NMDs 512, 514, and 516 may be
components of devices having various primary utilities. For
instance, as discussed above in connection to FIGS. 2 and 3, one or
more of NMDs 512, 514, and 516 may be the microphone(s) 220 of
playback device 200 or the microphone(s) 310 of network device 300.
Further, in some cases, one or more of NMDs 512, 514, and 516 may
be the playback device 200 or network device 300. In an example,
one or more of NMDs 512, 514, and/or 516 may include multiple
microphones arranged in a microphone array.
[0072] As shown, the computing device 506 may be configured to
interface with CR 522 and PBDs 532, 534, 536, and 538 via
communication path 544. In one example, CR 522 may be a network
device such as the network device 200 of FIG. 2. Accordingly, CR
522 may be configured to provide the controller interface 400 of
FIG. 4. Similarly, PBDs 532, 534, 536, and 538 may be playback
devices such as the playback device 300 of FIG. 3. As such, PBDs
532, 534, 536, and 538 may be physically distributed throughout a
household as shown in FIG. 1. For illustration purposes, PBDs 536
and 538 may be part of a bonded zone 530, while PBDs 532 and 534
may be part of their own respective zones. As described above, the
PBDs 532, 534, 536, and 538 may be dynamically bonded, grouped,
unbonded, and ungrouped. Communication path 544 may comprise one or
more types of networks, such as a WAN including the Internet, LAN,
and/or PAN, among other possibilities.
[0073] In one example, as with NMDs 512, 514, and 516, CR522 and
PBDs 532, 534, 536, and 538 may also be components of one or more
"Smart Home" systems. In one case, PBDs 532, 534, 536, and 538 may
be distributed throughout the same household as the NMDs 512, 514,
and 516. Further, as suggested above, one or more of PBDs 532, 534,
536, and 538 may be one or more of NMDs 512, 514, and 516.
[0074] The NMDs 512, 514, and 516 may be part of a local area
network, and the communication path 542 may include an access point
that links the local area network of the NMDs 512, 514, and 516 to
the computing device 504 over a WAN (communication path not shown).
Likewise, each of the NMDs 512, 514, and 516 may communicate with
each other via such an access point.
[0075] Similarly, CR 522 and PBDs 532, 534, 536, and 538 may be
part of a local area network and/or a local playback network as
discussed in previous sections, and the communication path 544 may
include an access point that links the local area network and/or
local playback network of CR 522 and PBDs 532, 534, 536, and 538 to
the computing device 506 over a WAN. As such, each of the CR 522
and PBDs 532, 534, 536, and 538 may also communicate with each over
such an access point.
[0076] In one example, a single access point may include
communication paths 542 and 544. In an example, each of the NMDs
512, 514, and 516, CR 522, and PBDs 532, 534, 536, and 538 may
access the cloud network 502 via the same access point for a
household.
[0077] As shown in FIG. 5, each of the NMDs 512, 514, and 516, CR
522, and PBDs 532, 534, 536, and 538 may also directly communicate
with one or more of the other devices via communication means 546.
Communication means 546 as described herein may involve one or more
forms of communication between the devices, according to one or
more network protocols, over one or more types of networks, and/or
may involve communication via one or more other network devices.
For instance, communication means 546 may include one or more of
for example, Bluetooth.TM. (IEEE 802.15), NFC, Wireless direct,
and/or Proprietary wireless, among other possibilities.
[0078] In one example, CR 522 may communicate with NMD 512 over
Bluetooth.TM., and communicate with PBD 534 over another local area
network. In another example, NMD 514 may communicate with CR 522
over another local area network, and communicate with PBD 536 over
Bluetooth. In a further example, each of the PBDs 532, 534, 536,
and 538 may communicate with each other according to a spanning
tree protocol over a local playback network, while each
communicating with CR 522 over a local area network, different from
the local playback network. Other examples are also possible.
[0079] In some cases, communication means between the NMDs 512,
514, and 516, CR 522, and PBDs 532, 534, 536, and 538 may change
depending on types of communication between the devices, network
conditions, and/or latency demands. For instance, communication
means 546 may be used when NMD 516 is first introduced to the
household with the PBDs 532, 534, 536, and 538. In one case, the
NMD 516 may transmit identification information corresponding to
the NMD 516 to PBD 538 via NFC, and PBD 538 may in response,
transmit local area network information to NMD 516 via NFC (or some
other form of communication). However, once NMD 516 has been
configured within the household, communication means between NMD
516 and PBD 538 may change. For instance, NMD 516 may subsequently
communicate with PBD 538 via communication path 542, the cloud
network 502, and communication path 544. In another example, the
NMDs and PBDs may never communicate via local communications means
546. In a further example, the NMDs and PBDs may communicate
primarily via local communications means 546. Other examples are
also possible.
[0080] In an illustrative example, NMDs 512, 514, and 516 may be
configured to receive voice inputs to control PBDs 532, 534, 536,
and 538. The available control commands may include any media
playback system controls previously discussed, such as playback
volume control, playback transport controls, music source
selection, and grouping, among other possibilities. In one
instance, NMD 512 may receive a voice input to control one or more
of the PBDs 532, 534, 536, and 538. In response to receiving the
voice input, NMD 512 may transmit via communication path 542, the
voice input to computing device 504 for processing. In one example,
the computing device 504 may convert the voice input to an
equivalent text command, and parse the text command to identify a
command. Computing device 504 may then subsequently transmit the
text command to the computing device 506. In another example, the
computing device 504 may convert the voice input to an equivalent
text command, and then subsequently transmit the text command to
the computing device 506. The computing device 506 may then parse
the text command to identify one or more playback commands.
[0081] For instance, if the text command is "Play `Track 1` by
`Artist 1` from `Streaming Service 1` in `Zone 1`," The computing
device 506 may identify (i) a URL for "Track 1" by "Artist 1"
available from "Streaming Service 1," and (ii) at least one
playback device in "Zone 1." In this example, the URL for "Track 1"
by "Artist 1" from "Streaming Service 1" may be a URL pointing to
computing device 508, and "Zone 1" may be the bonded zone 530. As
such, upon identifying the URL and one or both of PBDs 536 and 538,
the computing device 506 may transmit via communication path 544 to
one or both of PBDs 536 and 538, the identified URL for playback.
One or both of PBDs 536 and 538 may responsively retrieve audio
content from the computing device 508 according to the received
URL, and begin playing "Track 1" by "Artist 1" from "Streaming
Service 1."
[0082] One having ordinary skill in the art will appreciate that
the above is just one illustrative example, and that other
implementations are also possible. In one case, operations
performed by one or more of the plurality of devices 500, as
described above, may be performed by one or more other devices in
the plurality of device 500. For instance, the conversion from
voice input to the text command may be alternatively, partially, or
wholly performed by another device or devices, such as NMD 512,
computing device 506, PBD 536, and/or PBD 538. Analogously, the
identification of the URL may be alternatively, partially, or
wholly performed by another device or devices, such as NMD 512,
computing device 504, PBD 536, and/or PBD 538.
f. Example Network Microphone Device
[0083] FIG. 6 shows a functional block diagram of an example
network microphone device 600 that may be configured to be one or
more of NMDs 512, 514, and 516 of FIG. 5. As shown, the network
microphone device 600 includes a processor 602, memory 604, a
microphone array 606, a network interface 608, a user interface
610, software components 612, and speaker(s) 614. One having
ordinary skill in the art will appreciate that other network
microphone device configurations and arrangements are also
possible. For instance, network microphone devices may
alternatively exclude the speaker(s) 614 or have a single
microphone instead of microphone array 606.
[0084] The processor 602 may include one or more processors and/or
controllers, which may take the form of a general or
special-purpose processor or controller. For instance, the
processing unit 602 may include microprocessors, microcontrollers,
application-specific integrated circuits, digital signal
processors, and the like. The memory 604 may be data storage that
can be loaded with one or more of the software components
executable by the processor 602 to perform those functions.
Accordingly, memory 604 may comprise one or more non-transitory
computer-readable storage mediums, examples of which may include
volatile storage mediums such as random access memory, registers,
cache, etc. and non-volatile storage mediums such as read-only
memory, a hard-disk drive, a solid-state drive, flash memory,
and/or an optical-storage device, among other possibilities.
[0085] The microphone array 606 may be a plurality of microphones
arranged to detect sound in the environment of the network
microphone device 600. Microphone array 606 may include any type of
microphone now known or later developed such as a condenser
microphone, electret condenser microphone, or a dynamic microphone,
among other possibilities. In one example, the microphone array may
be arranged to detect audio from one or more directions relative to
the network microphone device. The microphone array 606 may be
sensitive to a portion of a frequency range. In one example, a
first subset of the microphone array 606 may be sensitive to a
first frequency range, while a second subset of the microphone
array may be sensitive to a second frequency range. The microphone
array 606 may further be arranged to capture location information
of an audio source (e.g., voice, audible sound) and/or to assist in
filtering background noise. Notably, in some embodiments the
microphone array may consist of only a single microphone, rather
than a plurality of microphones.
[0086] The network interface 608 may be configured to facilitate
wireless and/or wired communication between various network
devices, such as, in reference to FIG. 5, CR 522, PBDs 532-538,
computing device 504-508 in cloud network 502, and other network
microphone devices, among other possibilities. As such, network
interface 608 may take any suitable form for carrying out these
functions, examples of which may include an Ethernet interface, a
serial bus interface (e.g., FireWire, USB 2.0, etc.), a chipset and
antenna adapted to facilitate wireless communication, and/or any
other interface that provides for wired and/or wireless
communication. In one example, the network interface 608 may be
based on an industry standard (e.g., infrared, radio, wired
standards including IEEE 802.3, wireless standards including IEEE
802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.15, 4G mobile
communication standard, and so on).
[0087] The user interface 610 of the network microphone device 600
may be configured to facilitate user interactions with the network
microphone device. In one example, the user interface 608 may
include one or more of physical buttons, graphical interfaces
provided on touch sensitive screen(s) and/or surface(s), among
other possibilities, for a user to directly provide input to the
network microphone device 600. The user interface 610 may further
include one or more of lights and the speaker(s) 614 to provide
visual and/or audio feedback to a user. In one example, the network
microphone device 600 may further be configured to playback audio
content via the speaker(s) 614.
[0088] Moving now to several example implementations,
implementations 700, 900 and 1100 shown in FIGS. 7, 9, and 11,
respectively present example embodiments of techniques described
herein. These example embodiments that can be implemented within an
operating environment including, for example, the media playback
system 100 of FIG. 1, one or more of the playback device 200 of
FIG. 2, or one or more of the control device 300 of FIG. 3, as well
as other devices described herein and/or other suitable devices.
Further, operations illustrated by way of example as being
performed by a media playback system can be performed by any
suitable device, such as a playback device or a control device of a
media playback system. Implementations 700, 900, and 1100 may
include one or more operations, functions, or actions as
illustrated by one or more of blocks shown in FIGS. 7, 9, and 11.
Although the blocks are illustrated in sequential order, these
blocks may also be performed in parallel, and/or in a different
order than those described herein. Also, the various blocks may be
combined into fewer blocks, divided into additional blocks, and/or
removed based upon the desired implementation.
[0089] In addition, for the implementations disclosed herein, the
flowcharts show functionality and operation of one possible
implementation of present embodiments. In this regard, each block
may represent a module, a segment, or a portion of program code,
which includes one or more instructions executable by a processor
for implementing specific logical functions or steps in the
process. The program code may be stored on any type of computer
readable medium, for example, such as a storage device including a
disk or hard drive. The computer readable medium may include
non-transitory computer readable medium, for example, such as
computer-readable media that stores data for short periods of time
like register memory, processor cache, and Random Access Memory
(RAM). The computer readable medium may also include non-transitory
media, such as secondary or persistent long term storage, like read
only memory (ROM), optical or magnetic disks, compact-disc read
only memory (CD-ROM), for example. The computer readable media may
also be any other volatile or non-volatile storage systems. The
computer readable medium may be considered a computer readable
storage medium, for example, or a tangible storage device. In
addition, for the implementations disclosed herein, each block may
represent circuitry that is wired to perform the specific logical
functions in the process.
III. EXAMPLE TECHNIQUES TO DUCK AUDIO
[0090] As discussed above, embodiments described herein may
facilitate speech comprehension in the presence of noise, such as
music playback. FIG. 7 illustrates an example implementation 700 by
which a playback device ducks audio being played back. Such ducking
may improve speech comprehension in the presence of the played back
audio.
a. Detect That an Event is Anticipated in a Given Environment
[0091] At block 702, implementation 700 involves detecting that an
event is anticipated in a given environment. For instance, a
playback device, such as playback device 114 of media playback
system 100, may detect that an event is anticipated in a given
environment (e.g., within the example home environment or a subset
of its rooms and spaces, such as in the Kitchen). Such an
anticipated event may be an event that is expected or predicted to
occur but has not yet taken place (or perhaps has not fully taken
place). During the event (or a portion thereof), audio that is
being played by one or more playback devices of a media playback
system (e.g., any of playback devices 102-124 of media playback
system 100) may be ducked. Ducking is an audio effect by which the
level of one audio signal is reduced during the presence of another
audio signal.
[0092] As noted above, audio that is being played back may be
ducked. Implementation 700 may involve detecting that an event is
anticipated while playing back first audio in the given
environment. The first audio might be music, talk radio or other
programming, television or home theater content, audio from an
analog or digital line-in to the playback device, as well as other
types of audio or a combination of multiple types of audio.
Ultimately, the playback device may duck the first audio during the
event (or during a portion of the event).
[0093] Some example events may involve playback of second audio.
Detecting that such an event is anticipated may involve detecting
that playback of the second audio is anticipated. A playback device
may anticipate playback of second audio when the playback device
receives an instruction to playback the second audio via a network
interface (and/or receives the second audio itself for playback,
perhaps as an audio stream). Alternatively, a first playback device
(e.g., playback device 112) may detect that playback of the second
audio by one or more second playback devices is anticipated,
perhaps by receiving a transmission indicating that the one or more
second playback devices (e.g., one or more of the playback devices
of media playback system 100) are expected to play back second
audio.
[0094] In some cases, the second audio may be related to a voice
service. Some voice services include artificial intelligence to
process voice inputs and generate responses to those voice inputs.
For instance, the second audio may include a spoken voice input to
a voice service (e.g., "Hey Kitchen, what is the weather today?").
The second audio may additionally or alternatively include a spoken
response to a voice input (e.g., "The weather is clear and sunny
with a high of 75 degrees and a low of 68 degrees"). The playback
device may receive such a response via a network interface from a
voice service or from an NMD, among other sources.
[0095] Detecting that an event is anticipated in a given
environment may involve receiving an indication that a voice
command with the given environment is anticipated. For instance, an
NMD (e.g., NMD 132 of FIG. 1) may detect a voice input and transmit
an indication to playback device 114 that second audio is
anticipated. Detecting that an event is anticipated in the given
environment may involve receiving that indication.
[0096] In some cases, a voice input may include a wake word and a
voice command. Detection of a spoken wake-word (e.g., "Hey Siri,"
"Ok, Google," "Sonos," or "Hey, Alexa," among others) may cause a
NMD to start listening for a voice command. As such, detection of a
wake word may indicate that a voice command is expected in the
given environment. A playback device may detect that an event
(e.g., a voice command and/or an audio response to the voice
command) is anticipated by receiving an indication from an NMD that
a wake word was detected. Alternatively, an NMD may be integrated
with a playback device. In such implementations, the playback
device may detect that an event is anticipated by detecting a voice
input via one or more microphones (e.g., a far-field microphone
array). The voice input or a portion thereof (e.g., a wake-word)
may cause the playback device to anticipate the event (e.g., second
audio include a voice command and/or an audio response to the voice
command).
[0097] The second audio might include other audio streams as well.
Example streams include any stream from a cloud services (e.g., a
stream from a home cloud service indicating that a "smart" device
(e.g., an appliance or other smart home device with an processor
and network interface) is experiencing a condition. For instance,
"smart" thermostat may cause a various audio streams indicating
respective conditions to be played back (e.g., "HVAC system
cooling" or "HVAC system fault").
[0098] Other example streams may be sent from other
network-connected devices within the environment. For instance, a
"smart" doorbell may instruct the playback device to output a
doorbell track (e.g., a chime) perhaps by streaming the doorbell
track to the playback device. As another example, a "smart"
refrigerator may stream a spoken message (e.g., a message
indicating that certain food is past its expiration date).
Detecting that an event is anticipated may involve receiving an
instruction to play back such a stream, receiving the stream
itself, or receiving an indication that another playback device is
instructed to play back the stream, among other examples.
[0099] In some examples, detecting that an event is anticipated may
involve detecting input data from one or more control interfaces
(e.g., controller interface 400 displayed on a control device or a
physical button on a playback device, among other options). The
input data may indicate an instruction that causes the playback
device to play back second audio. As noted above, the second audio
may include a spoken response from a voice service, an audio stream
from a "smart" device, or an audio stream from a cloud service,
among other examples. For instance, a remote control may include a
microphone button that causes the remote control to start listening
for a voice input via one or more microphones. Detecting a press of
such a button may cause the playback device to anticipate an event
that involves second audio within the environment (e.g., a voice
input and/or an audio response to that voice input).
[0100] As noted above, a playback device may detect that the event
is anticipated while playing back first audio in the given
environment. For instance, playback device 114 of media playback
system 100 in FIG. 1 may stream first audio and play the streamed
audio in the Kitchen. In some cases, the playback device may be
part of a grouping of playback devices, such as a bonded zone or
zone group. In such cases, playing back first audio in the given
environment may involve playing audio in synchrony with other
playback devices in the grouping. For instance, playback devices
104, 106, 108, and 110 may play back respective channels of first
audio that includes surround sound (e.g., home theater) audio. As
another example, playback devices 104, 106, 108, 110, 112 and 114
may be joined into a zone group to play music in synchrony. Many
examples are possible.
b. Determine Loudness of Background Noise in Given Environment
[0101] Referring back to FIG. 7, at block 704, implementation 700
involves determining a loudness of background noise in the given
environment. For instance, the playback device may measure
background noise in the given environment using one or more
microphones. Alternatively, the playback device may transmit a
request that causes one or more NMDs to measure background noise in
the given environment. The background noise may include ambient
noise within the given environment (e.g., conversations between
people, appliances, HVAC, outdoor noise such as traffic, among
other possible sources). The playback device may determine loudness
while playing back the first audio in the given environment.
[0102] In some cases, multiple NMDs may perform the measurement of
background noise. For instance, the playback device may transmit to
multiple NMDs respective requests to measure background noise.
Alternatively, one or more first NMDs may receive an instruction to
measure background noise and cause one or more second NMDs to
measure background noise. The NMDs may measure the background noise
using one or more microphones (e.g., using a far-field microphone
array). For instance, NMD 132 and control devices 126 shown in
Figure (which may have an integrated NMD) may each perform a
measurement of background noise within the Living Room/Dining
Room/Kitchen environment.
[0103] A suitable processing device, such as the playback device or
an NMD, may combine multiple measurements of background noise to
yield a representation of loudness of background noise in the given
environment. In some cases, the processing device may average
multiple measurements of background noise to determine the
loudness. In some cases, measurements from respective NMDs may be
weighted (e.g., prioritized) differently, perhaps based on the
quality of measurement. Quality of measurement may vary based on an
NMD's position within the given environment (which may influence
how well the NMD is able to measure background noise), the quality
of microphone(s) used to measure background noise, or other factors
that might influence measurement quality.
[0104] In some implementations, the processing device may offset
the first audio that the playback device is playing back within the
measurement of background noise in the given environment. By
offsetting the first audio from the measurement, the measurement
may more accurately represent the ambient noise other than the
first audio that is present within the environment.
[0105] Various techniques may be used to offset the first audio
from the measurement. For instance, the measurement may use
acoustic echo cancellation or beam-forming to offset the first
audio from the measurement, among other suitable recording
techniques. Alternatively, the acoustic response of the playback
device and the first audio may each be known, such that the
response produced by the playback device in playing back the first
audio is known (to at least some approximate degree). With this
response known, the processing device can offset the first audio
from a measurement of background noise by subtraction. Other
techniques are possible as well.
[0106] In some cases, the measurement device(s) and/or the
processing device(s) may transmit measurement(s) of background
noise to the playback device. This measurement may be represented
as a decibel value of a known scale or an identifier of a range
(e.g., a loudness-window) in which the loudness measurement falls,
among any suitable indication of the measured loudness. In some
cases, the transmission may represent an error state indicating
that a loudness measurement could not be obtained.
[0107] As indicated above, in some cases, the playback device might
not be able to obtain a loudness measurement. For instance, there
might not be any suitable NMDs within the given environment to
perform the measurement. Or, as another example, there may be a
connection issue between NMDs within the given environment and the
playback device. Other issues are possible as well.
[0108] When the playback device is unable to obtain a measurement
of the background noise, the playback device may estimate the
background noise. For instance, the playback device may estimate
the background noise as some default background noise level.
Alternatively, the playback device may estimate the background
noise as the last known background noise level within the
environment.
[0109] As yet another example, the playback device may estimate the
background noise based on a measurement of background noise in
another room. For example, playback device 114 may estimate
background noise in the Living Room/Dining Room/Kitchen environment
using a measurement of background noise in the Bedroom environment
from control device 128. The estimate of background noise in the
Living Room/Dining Room/Kitchen environment based the measurement
of background noise in the Bedroom environment may be adjusted
based on the relative locations of two environments and any
obstructions between the two environments, which may be known.
Emitting sound in one environment and recording that sound in
another may facilitate mapping transforms between environments
(e.g., between rooms or spaces).
c. Duck the First Audio
[0110] In FIG. 7, at block 706, implementation 700 involves ducking
the first audio. For instance, the playback device may duck the
first audio that is being played back by the playback device. As
noted above, ducking is an audio effect by which the level of one
audio signal is reduced during the presence of another audio
signal. As used herein, ducking may refer to volume reduction of
the first audio that the playback device is playing back during the
anticipated event. For example, the playback device may reduce the
volume of the first audio while the second audio is present (e.g.,
playing back or being spoken).
[0111] As noted above, in some instances, the anticipated event may
involve second audio. The second audio may include a voice input
and/or a spoken response from a voice service to a voice input. In
some examples, the playback device ducks the first audio (e.g., one
or more audio tracks, such as music) during the voice input and/or
during the spoken response from the voice service. Such ducking may
assist an NMD in comprehending the voice input and/or a user in
comprehending a spoken response.
[0112] The amount of ducking (i.e., the amount of volume reduction
of the first audio) may vary based on desired outcomes of the
ducking. For instance, the loudness of the first audio may be
reduced to the volume level of the second audio such that the first
audio and the second audio are output at approximately equal
loudness levels. Other examples are possible.
[0113] In some examples, the first audio may be ducked by a
specific amount based on the difference between loudness of the
first audio and the background noise. For instance, where the
playback device is playing back the first audio at a given
loudness, the playback device may duck the first audio in
proportion to the difference between the given loudness and the
determined loudness of the background noise. Ducking the first
audio by such an amount may assist in keeping the ducked first
audio above the noise floor.
[0114] To illustrate, in one example a party might be held in the
Living Room/Dining Room/Kitchen area shown in FIG. 1. During the
party, playback devices 104, 106, 108, 110, 112, and/or 114 may
play back first audio (e.g., music) at a given volume level. Music
played at that volume level may generate a dynamic range centered
around a given loudness. The dynamic range of the first audio is
the difference between the quiet and loudest parts of the first
audio. Talking, dancing, and/or other actions by guests at the
party may generate a relatively high level of background noise.
Given this relatively loud background noise, if the first audio is
set at a relatively low volume, some part of the first audio (i.e.,
the quiet parts of music at the low end of the dynamic range) may
be below the noise floor. Alternatively, if the first audio is set
at a relatively high volume, more (or all) of the first audio may
be above the noise floor. When the first audio is ducked, the
quieter parts of the first audio may go below the noise floor.
Ducking the first audio in proportion to the difference between the
given loudness and the determined loudness of the background noise
may help to avoid portions of the first audio being lost under the
noise floor.
[0115] As noted above, in some examples, the playback device may
duck the first audio while the second audio is present. FIG. 8
includes a chart 800. In chart 800, time is plotted along the
x-axis and loudness is plotted along the y-axis. At time t.sub.0, a
playback device is playing first audio 802 at loudness level
l.sub.0. From time t.sub.1 to time t.sub.2, the playback device
reduces the loudness of first audio 802 from loudness level l.sub.0
to loudness level l.sub.1 so as to duck the first audio 802 in the
presence of second audio 804.
[0116] In some cases, the playback device may duck the first audio
itself. For instance, the playback device may adjust an amplifier
level to reduce the volume of the first audio. Alternatively, the
playback device may apply a filter to reduce the volume of the
first audio. As yet another example, another device may process the
first audio to reduce the volume of the first audio. Other examples
are possible as well.
d. Play Back the Ducked First Audio Concurrently with the Second
Audio
[0117] In FIG. 7, at block 708, implementation 700 involves playing
back the ducked first audio concurrently with the second audio. For
instance, the playback device may receive a stream of the second
audio and play back that stream of second audio concurrently with
the ducked first audio. As noted above, a playback device may
receive a spoken response to a voice input from a voice service or
intermediary device. The playback device may play back ducked music
(e.g., one or more audio tracks) concurrently with the spoken
response from a voice input. As another example, the playback
device may play back a ducked streaming radio station concurrently
with an alarm from a "smart" device such as a doorbell or
refrigerator. In a further example, the second audio may be a phone
call and the playback device may play back audio from the phone
call concurrently with the ducked first audio. As noted above, many
different types of first and second audio are contemplated.
[0118] As noted above, a playback device may be part of grouping of
playback devices, such as a bonded zone or zone group. In such
cases, the playback device may play the first audio in synchrony
with other playback devices in the grouping. In some
implementations, all of the playback devices in the grouping may
play back the ducked first audio concurrently with the second
audio. In other implementations, a subset of the playback devices
in the grouping may play back the ducked first audio concurrently
with the second audio, while the other playback devices continue to
play back the first audio without ducking. In yet further examples,
a subset of the playback devices in the grouping may play back the
second audio while the other playback devices play back the first
audio. Other examples are possible as well.
[0119] The playback device may continue to duck the first audio
until the anticipated event has completed or until a future event
occurs, among other examples. For instance, if the event is a voice
interaction with a voice service, the playback device may duck the
first audio while a user is speaking a voice input and/or while
playing back a spoken response from the voice service. As another
example, if the event is a phone call, the playback device may duck
the first audio until the phone call ends (e.g., until the parties
hang up). Generally, in examples where the second audio is an audio
stream, the playback device may duck the first audio until the
second audio completes play back.
[0120] To illustrate, referring back to FIG. 8, the second audio
804 is output from time t.sub.2 to t.sub.3. The first audio 802 is
ducked from time t.sub.2 until t.sub.3. Time t.sub.3 may correspond
to the end of the anticipated event beginning at t.sub.2 or to a
future event detected by the playback device. From time t.sub.3 to
t.sub.4, the ducking is reversed by raising the volume level from
l.sub.1 to l.sub.2.
IV. EXAMPLE TECHNIQUES TO COMPRESS AUDIO
[0121] As discussed above, embodiments described herein may
facilitate compressing audio in the presence of second audio. FIG.
9 illustrates an example implementation 900 by which a playback
device compresses first audio. The playback device may compress the
first audio while ducking the first audio, as described above in
connection with implementation 700.
a. Determine Loudness of First Audio and Background Noise
[0122] At block 902, implementation 900 involves determining a
loudness of first audio and background noise in a given
environment. For instance, a playback device may determine the
loudness of first audio played back by the playback device (and
possibly one or more additional playback devices in synchrony with
the playback device). The first audio may be any suitable audio,
such as any of the examples of first audio discussed above in
connection with implementation 700, among other examples. The
playback device may determine a loudness of background noise using
any suitable technique, such as the example techniques described in
connection with block 704 of implementation 700.
[0123] In some instances, the first audio may be ducked first
audio, such as the ducked first audio discussed above in connection
with implementation 700. Ducked first audio may refer to audio that
has been temporarily reduced in volume based on the presence of
second audio.
[0124] The playback device may determine the loudness of the first
audio using any suitable technique. For instance, the playback
device may have a known volume setting (perhaps reduced by a known
amount through ducking). The playback device may have a known
equalization. Furthermore, the playback device may have a known
response in the given environment, perhaps via a calibration
procedure. The first audio may have a known or assumed level (e.g.,
-6 dB from an average master). Given one or more of these known
values, the playback device may estimate the loudness of the first
audio.
b. Compare Determined Loudness of First Audio with Loudness of
Background Noise
[0125] In FIG. 9, at block 904, implementation 900 involves
comparing the determined loudness of the first audio with the
determined loudness of the background noise. For instance, a
playback device may determine a difference between a loudness of
first audio (possibly ducked first audio) and a given dynamic
range. The playback device may further determine whether the
difference between the loudness of the (ducked) first audio and the
given dynamic range is less than or greater than the determined
loudness of the background noise. The given dynamic range may be a
desired dynamic range of the first audio (e.g., a dynamic range of
music playback).
c. Compressing First Audio
[0126] In FIG. 9, at block 906, implementation 900 involves
compressing the first audio. The playback device may compress the
first audio when the determined difference between the loudness of
the (ducked) first audio and the given dynamic range is less than
the determined loudness of the background noise. This determination
may indicate that a portion of the dynamic range of the first audio
is below the noise floor created by the background noise. By
compressing the first audio in such circumstances, some or all of
the dynamic range of the first audio may be raised above the noise
floor. When the determined difference between the loudness of the
(ducked) first audio and the given dynamic range is greater than
the determined loudness of the background noise, the playback might
not apply compression since such compression might be unnecessarily
reduce the dynamic range of the first audio.
[0127] The amount of compression may be a function of the
difference between the determined loudness of the background noise
and the given dynamic range. For instance, when the difference is
relatively large such that the low end of the dynamic range is
relatively further below the noise floor created by the background
noise, then the playback device may compress the first audio more
to bring more (or all) of the dynamic range above the noise floor.
Conversely, when the difference is relatively small such that the
low end of the dynamic range is just below the noise floor, the
playback device might compress the dynamic range of the first audio
relatively less.
[0128] To illustrate, FIG. 10 is a diagram illustrating a dynamic
range 1000A of first audio (e.g., music) and a dynamic range 1002A
of second audio (e.g., voice). As shown, dynamic range 1000A and
dynamic range 1002 overlap, which may make the first audio and/or
the second audio hard to comprehend. At time t.sub.1, the first
audio is ducked, which causes a dynamic range 1000B of the ducked
first audio to be below the dynamic range 1002 of the second audio.
However, when ducked, the dynamic range of the first audio is below
a noise floor 1004. In this case, quiet details in the first audio
may be indiscernible over background noise. At time t.sub.2, the
ducked first audio is compressed, which causes a dynamic range
1000C of the ducked and compressed audio to be above the noise
floor 1004. Although FIG. 10 describes ducking and compression as
occurring in a particular order, these operations may be performed
concurrently or in a different order.
[0129] Although examples techniques described in connection with
implementation 1000 describe compression being applied based on a
comparison between the determined loudness of background noise and
the first audio, compression may be applied to the first audio
under other conditions as well. For instance, compression may be
applied based on content type (e.g., applied to music or talk
radio) or background noise level, among other options. In some
cases, compression is always applied to first audio when second
audio is present.
V. EXAMPLE TECHNIQUES TO APPLY EQUALIZATION
[0130] As discussed above, embodiments described herein may improve
speech-to-noise ratio within a given environment. FIG. 11
illustrates an example implementation 1100 by which a playback
device selectively applies an equalization to audio content being
played back.
a. Play Audio Content in Given Environment
[0131] At block 1102, implementation 1100 involves playing audio
content in a given environment. For instance, one or more playback
devices (e.g., any combination of playback devices 102-124 in FIG.
1) may play back audio content in one or more rooms of the example
home environment in FIG. 1. In one example, playback devices 112
and 114 may play back music in the Kitchen/Dining Room environment.
The audio content may be music or any other suitable audio
content.
b. Detect that a Signal-to-Noise Ratio in Given Environment is
Below Speech Threshold
[0132] In FIG. 11, at block 1104, implementation 1100 involves
detecting that a signal-to-noise ratio in the given environment is
below a speech threshold. For instance, a playback device (e.g.,
playback device 114 of FIG. 1) may determine that a signal-to-noise
ratio in a given environment (i.e., the Kitchen or the combined
Dining Room/Kitchen area) is below a speech threshold. A
signal-to-noise ratio that is below the speech threshold may
indicate that an improvement to signal-to-noise ratio in the given
environment would facilitate comprehension of speech in that
environment.
[0133] In some implementations, detecting that the signal-to-noise
ratio in the given environment is below the speech threshold may
involve detecting a number of people in the given environment. The
playback device may assume that the signal-to-noise ratio in the
given environment is below the speech threshold when there are more
than a given number of people in the room (e.g., two or more). The
playback device may detect a number of people in the environment by
detecting signals from their respective smartphones or other
devices using a network interface (e.g., using Bluetooth.RTM.
beacons or WiFi.RTM. device detection). In another case, the
playback device may detect sound pressure level of background noise
in the given environment, perhaps by querying one or more NMDs for
a measurement. A high sound pressure level of background noise may
indicate that the signal-to-noise ratio in the given environment is
below the speech threshold. In further implementations, user input
may indicate a number of persons in the environment.
[0134] In other cases, the playback device may anticipate that
speech will be present in the environment. For example, the
playback device may receive an indication of a wake-word in the
given environment, which may cause the playback device to
anticipate a voice command. In other examples, the playback device
may receive an audio stream representing speech to be played back
by the playback device. Alternatively, the playback device may
receive an indication that another playback device in the
environment is outputting speech. The speech may be audio of a
telephone call or a spoken response from a voice service, among
other examples of human or computer-generated speech. When speech
is present in the environment, the playback device may assume that
the signal-to-noise ratio in the given environment is below the
speech threshold.
c. Apply Equalization to Audio Content
[0135] In FIG. 11, at block 1106, implementation 1100 involves
applying an equalization to the audio content. For instance,
playback device 114 may filter the audio content (e.g., using one
or more digital or analog filters) to a particular equalization.
The equalization may cut the audio content at frequencies in the
audio content corresponding to human speech (e.g., 150 Hz-3 kHz).
Such filtering may include filtering at the fundamental frequencies
of human speech (e.g., 100 Hz for males and 180 Hz for females). In
some cases, the filtering may cut the audio content more at the
fundamental frequencies of human speech. Filtering the audio
content to reduce volume in frequencies corresponding to human
speech may improve the speech-to-noise ratio in the given
environment.
[0136] Filtering of frequencies in the audio content corresponding
to human speech may reduce overall perceived loudness of the audio
content. In some cases, the playback devices may offset this
decrease in overall loudness by boosting frequencies above and/or
below the frequencies in the audio content corresponding to human
speech (e.g., bass and treble frequencies). In some cases, the
playback device may use an equal loudness matching algorithm to
boost frequencies by specific amounts to offset cutting of the
frequencies in the audio content corresponding to human speech.
Alternatively, overall gain of the audio content may be increased
to offset the filtering of frequencies in the audio content
corresponding to human speech.
[0137] The playback device may continue to filter the audio content
while the signal-to-noise ratio in the given environment is below
the speech threshold, among other examples. For instance, if the
event is a voice interaction with a voice service, the playback
device may filter the audio content while a user is speaking a
voice input and/or while playing back a spoken response from the
voice service. As another example, if the event is a phone call,
the playback device may filter the audio content until the phone
call ends (e.g., until the parties hang up). Other examples are
possible as well.
VI. CONCLUSION
[0138] The description above discloses, among other things, various
example systems, methods, apparatus, and articles of manufacture
including, among other components, firmware and/or software
executed on hardware. It is understood that such examples are
merely illustrative and should not be considered as limiting. For
example, it is contemplated that any or all of the firmware,
hardware, and/or software aspects or components can be embodied
exclusively in hardware, exclusively in software, exclusively in
firmware, or in any combination of hardware, software, and/or
firmware. Accordingly, the examples provided are not the only
way(s) to implement such systems, methods, apparatus, and/or
articles of manufacture.
[0139] (Feature 1) A method comprising while playing back first
audio in a given environment at a given loudness: (a) detecting
that an event is anticipated in the given environment, wherein the
event involves playback of second audio and (b) determining a
loudness of background noise in the given environment, wherein the
background noise comprises ambient noise in the given environment;
ducking the first audio in proportion to a difference between the
given loudness of the first audio and the determined loudness of
the background noise; and playing back the ducked first audio
concurrently with the second audio.
[0140] (Feature 2) The method of feature 1, wherein playing back
the ducked first audio concurrently with the second audio comprises
determining that a difference between a loudness of the ducked
first audio and a given dynamic range is (a) less than the
determined loudness of the background noise or (b) greater than the
determined loudness of the background noise; when the determined
difference between the loudness of the ducked first audio and the
given dynamic range is less than the determined loudness of the
background noise, compressing the first audio to a dynamic range
that is louder than the determined loudness of the background noise
and playing back the compressed first audio; and when the
determined difference between the loudness of the ducked first
audio and the given dynamic range is greater than the determined
loudness of the background noise, playing back the first audio
without compression.
[0141] (Feature 3) The method of feature 1, wherein detecting that
the event is anticipated in the given environment comprises
receiving an indication that a voice command within the given
environment is anticipated.
[0142] (Feature 4) The method of feature 3, wherein receiving the
indication that the voice command within the given environment is
anticipated comprises detecting, via one or more microphones, a
voice input comprising a wake-word.
[0143] (Feature 5) The method of feature 3, wherein the first audio
comprises one or more audio tracks, wherein the second audio
comprises a spoken response to the voice command received from a
voice service, and wherein playing back the ducked first audio
concurrently with the second audio comprises playing back the one
or more audio tracks concurrently with the spoken response to the
voice command.
[0144] (Feature 6) The method of feature 3, wherein playing back
the ducked first audio concurrently with the second audio comprises
detecting that a signal-to-noise ratio within the given environment
is below a voice input threshold; and responsively, filtering the
first audio, wherein filtering the first audio comprises cutting
the first audio in a frequency range corresponding to human
speech.
[0145] (Feature 7) The method of feature 1, wherein filtering the
first audio further comprises boosting the first audio outside the
frequency range corresponding to human speech.
[0146] (Feature 8) The method of feature 1, wherein the playback
device is a first playback device of a group of playback device
that includes one or more second playback devices, and wherein
playing back the ducked first audio concurrently with the second
audio comprises playing back the ducked first audio concurrently
with the second audio in synchrony with the one or more second
playback devices.
[0147] (Feature 9) The method of feature 1, wherein determining the
loudness of background noise in the given environment comprises
measuring the loudness of the background noise in the given
environment via one or more microphone.
[0148] (Feature 10) The method of feature 9, wherein at least one
of the one or more microphones is housed in a networked microphone
device that is distinct from the playback device, and wherein
measuring the loudness of the background noise in the given
environment via one or more microphones comprises causing the
networked microphone device to measure the loudness of the
background noise in the given environment.
[0149] (Feature 11) The method of feature 9, wherein measuring the
loudness of the background noise in the given environment comprises
offsetting the first audio being played back by the playback device
from the measurement of the background noise in the given
environment.
[0150] (Feature 12) The method of feature 1, wherein the operations
further comprise detecting that the event has completed, and
wherein ducking the first audio comprises ducking the first audio
until the event has completed.
[0151] (Feature 13) A tangible, non-transitory computer-readable
medium having stored therein instructions executable by one or more
processors to cause a device to perform the method of any of
features 1-12.
[0152] (Feature 14) A playback device configured to perform the
method of any of features 1-12.
[0153] (Feature 15) A media playback system configured to perform
the method of any of features 1-12.
[0154] The specification is presented largely in terms of
illustrative environments, systems, procedures, steps, logic
blocks, processing, and other symbolic representations that
directly or indirectly resemble the operations of data processing
devices coupled to networks. These process descriptions and
representations are typically used by those skilled in the art to
most effectively convey the substance of their work to others
skilled in the art. Numerous specific details are set forth to
provide a thorough understanding of the present disclosure.
However, it is understood to those skilled in the art that certain
embodiments of the present disclosure can be practiced without
certain, specific details. In other instances, well known methods,
procedures, components, and circuitry have not been described in
detail to avoid unnecessarily obscuring aspects of the embodiments.
Accordingly, the scope of the present disclosure is defined by the
appended claims rather than the forgoing description of
embodiments.
[0155] When any of the appended claims are read to cover a purely
software and/or firmware implementation, at least one of the
elements in at least one example is hereby expressly defined to
include a tangible, non-transitory medium such as a memory, DVD,
CD, Blu-ray, and so on, storing the software and/or firmware.
* * * * *