PATENT DOCUMENT

Publication Number: US-8381107-B2
Application Number: US-68687610-A
Country: US
Kind Code: B2

Title: Adaptive audio feedback system and method

Abstract:
Various techniques for adaptively varying audio feedback data on an electronic device are provided. In one embodiment, an audio user interface implementing certain aspects of the present disclosure may devolve or evolve the verbosity of audio feedback in response to user interface events based at least partially upon the verbosity level of audio feedback provided during previous occurrences of the user interface event. In another embodiment, an audio user interface may be configured to vary the verbosity of audio feedback associated with a navigable list of items based at least partially upon the speed at which a user navigates the list. In a further embodiment, an audio user interface may be configured to vary audio feedback verbosity based upon the contextual importance of a user interface event. Electronic devices implementing the present techniques provide an improved user experience with regard to audio user interfaces.

Claims:
1. A method, comprising:
 using a processor on an electronic device to: 
 detect the occurrence of a user interface event requesting audio feedback on the electronic device at a first time; 
 identify a plurality of audio items associated with the user interface event, wherein the plurality of audio items comprises at least two verbal audio items and at least one non-verbal audio item, and wherein each verbal audio item of the plurality of audio items has a different level of verbosity comprising a different amount of spoken words; 
 select a first audio item from the plurality of audio items that corresponds to a first desired verbosity level determined based at least partially upon whether the user interface event previously occurred within a particular time interval prior to the first time; and 
 provide the audio feedback by playing back the selected first audio item on the electronic device using an audio output device. 
 
     
     
       2. The method of  claim 1 , wherein selecting the first audio item comprises:
 if the user interface event did not previously occur within the particular time interval prior to the first time, selecting an audio item having the highest level of verbosity from the plurality of audio items; and 
 if the user interface event previously occurred within the particular time interval prior to the first time, determining the verbosity level of an audio item selected from the plurality of audio items during the previous occurrence of the user interface event, and selecting an audio item from the plurality of audio items that is at least one step less verbose relative to the previously selected audio item. 
 
     
     
       3. The method of  claim 2 , comprising:
 detecting a subsequent occurrence of the user interface event on the electronic device at a second time; 
 selecting a second audio item from the plurality of audio items that corresponds to a second desired verbosity level determined based upon the duration between the first time and the second time; and 
 playing the selected second audio item on the electronic device using the audio output device. 
 
     
     
       4. The method of  claim 3 , wherein selecting the second audio item comprises:
 if the duration between the first and second times is less than or equal to the particular time interval, selecting an audio item from the plurality of audio items that is at least one step less verbose relative to the first audio item; and 
 if the duration between the first and second times is greater than the particular time interval, selecting an audio item from the plurality of audio items that is at least one step more verbose relative to the first audio item. 
 
     
     
       5. The method of  claim 4 , wherein selecting the audio item that is at least one step more verbose relative to the first audio item comprises selecting the audio item having the highest verbosity level within the plurality of audio items regardless of the verbosity level of the first audio item. 
     
     
       6. The method of  claim 2 , wherein selecting the first audio item comprises:
 determining whether a playback termination event was detected during the previous occurrence of the user interface event; and 
 if a playback termination event was detected during the previous occurrence, selecting an audio item from the plurality of audio items having a lower level of verbosity regardless of the verbosity level of the previously selected audio item. 
 
     
     
       7. The method of  claim 6 , wherein the audio item having the lower level of verbosity comprises a non-verbal audio item. 
     
     
       8. The method of  claim 6 , wherein a user termination event comprises a user input or a gesture that prematurely terminated the playback of the previously selected audio item. 
     
     
       9. The method of  claim 6 , comprising:
 if a playback termination event was not detected during the previous occurrence of the user interface event, using a graphical user interface to display a first visual notification at least partially concurrently with the playback of the selected first audio item; and 
 if a playback termination event was detected during the previous occurrence of the user interface event, using a graphical user interface to display a second visual notification substantially concurrently with the playback of the selected first audio item, wherein the second visual notification is less verbose relative to the first visual notification. 
 
     
     
       10. A method, comprising:
 using a processor on an electronic device to:
 identify a navigable set of data items stored on the electronic device; 
 receive an input from a user of the electronic device corresponding to a navigation event, wherein the navigation event includes a transition from a first data item to a second data item within the navigable set, such that the second data item becomes a currently selected data item; 
 detect a navigation speed corresponding to the navigation event; 
 vary audio feedback associated with the currently selected data item based at least partially upon the navigation speed; 
 determine whether the currently selected data item is newly acquired by the electronic device using a newness threshold; 
 play back a first non-verbal audio item if the currently selected data item is not newly acquired by the electronic device; and 
 play back a second non-verbal audio item if the currently selected data item is newly acquired by the electronic device, wherein the second non-verbal audio item is more audibly distinct relative to the first non-verbal audio item. 
 
 
     
     
       11. The method of  claim 10 , wherein varying the audio feedback comprises:
 at a first navigation speed, playing back a first audio item having full verbosity; and 
 at a second navigation speed, playing back a second audio item that is less verbose relative to the first audio item; 
 wherein the second navigation speed is greater than the first navigation speed. 
 
     
     
       12. The method of  claim 11 , the navigable set of data items is ordered alphabetically on the electronic device, and wherein selecting and playing back the second audio item comprises:
 if the currently selected data item is the first item of an alphabetical letter group, playing back the letter corresponding to the alphabetical letter group, or else playing back a non-verbal audio item. 
 
     
     
       13. The method of  claim 10 , wherein determining whether the currently selected data item includes new content comprises:
 determining the time at which the currently selected data item was acquired by the electronic device; 
 determining whether the acquisition time occurred within a particular time interval prior to the present time; 
 and identifying the currently selected data item as new content if the acquisition time occurred within the particular time interval, or else, identifying the currently selected data item as not being new content. 
 
     
     
       14. The method of  claim 10 , wherein the navigable set of data items stored on the electronic device is displayable as a list on a display device, and wherein the input from the user corresponds to a scroll command configured to navigate the displayed list. 
     
     
       15. A method, comprising:
 using a processor on an electronic device to:
 detect the occurrence of a user interface event requesting audio feedback on the electronic device; 
 identify a plurality of audio items associated with the user interface event, wherein the plurality of audio items comprises at least two verbal audio items and at least one non-verbal audio item; 
 select an audio item from the plurality of audio items based at least partially on whether the user interface event requests a decision input from the user; and 
 provide the audio feedback by playing back the selected audio item on the electronic device using an audio output device. 
 
 
     
     
       16. The method of  claim 15 , wherein the plurality of audio items comprises at least a first audio item and a second audio item, wherein the first and second audio items have the same level of verbosity. 
     
     
       17. The method of  claim 16 , wherein selecting the audio item comprises determining a contextual importance comprising:
 selecting the first audio item if the contextual importance is high; and 
 selecting the second audio item if the contextual importance is low; 
 wherein the first audio item is more audibly distinct relative to the first audio item. 
 
     
     
       18. The method of  claim 17 , wherein the contextual importance of the user interface event is determined to be high if the user interface event requests the decision input from the user of the electronic device. 
     
     
       19. The method of  claim 17 , wherein the first and second audio items each comprise non-verbal audio items. 
     
     
       20. The method of  claim 17 , wherein the first audio item has a more audibly distinct pitch, volume, playback time, or a combination thereof. 
     
     
       21. The method of  claim 15 , wherein the contextual importance of the user interface event is determined based upon information stored on the device, wherein the information stored on the device comprises one of pre-programmed information, or user-specified information configured through a set of user preference settings, or a combination thereof. 
     
     
       22. The method of  claim 15 , wherein the contextual importance of the user interface event is determined based upon the frequency at which the same type of user interface event occurred within a period of time just prior to the occurrence of the user interface event. 
     
     
       23. An electronic device, comprising:
 at least one storage device configured to store a plurality of audio items; 
 a user interface comprising an audio user interface, wherein the audio user interface comprises: 
 audio feedback selection logic configured to:
 detect the occurrence of a user interface event requesting audio feedback; 
 identify a set of audio items of the plurality of audio items associated with the user interface event, wherein the set of audio items comprises verbal and non-verbal audio items, and wherein the set of audio items has varying levels of verbosity comprising a lowest level that includes no spoken words, a highest level that includes a plurality of spoken words, and a level therebetween that includes at least one spoken word and fewer spoken words than the highest level; 
 determine a desired verbosity level based upon statistical data associated with the user interface event; 
 select from the set of audio items an audio item having a verbosity level corresponding to the desired verbosity level; and 
 initiate the playback of the selected audio item. 
 
 
     
     
       24. The electronic device of  claim 23 , wherein the selected audio item is played back on an audio output device comprising at least one of an integrated audio output device or an external audio output device coupled to the electronic device via an audio connection port, or a combination thereof. 
     
     
       25. The electronic device of  claim 23 , comprising a display, wherein the user interface comprises a graphical user interface configured to display a visual notification in response to the user interface event on the display, wherein the playback of the selected audio item is at least partially concurrent with the display of the visual notification. 
     
     
       26. The electronic device of  claim 23 , wherein the statistical data associated with the user interface event is stored in the at least one storage device. 
     
     
       27. The electronic device of  claim 26 , wherein the statistical data associated with the user interface event comprises data regarding previous occurrences of the user interface event, and wherein the determination of the desired verbosity level is based at least partially upon the verbosity level of an audio item selected during the most recent previous occurrence of the user interface event. 
     
     
       28. Audio processing circuitry comprising:
 one or more memory devices configured to store a plurality of audio items, wherein each of the plurality of audio items is selectable for playback in response to detection of an audio user interface event requesting audio feedback; and 
 audio feedback selection logic configured to detect the occurrence of an audio user interface event requesting audio feedback, identify from the plurality of audio items stored in the one or more memory devices a set of audio items comprising verbal and non-verbal audio items having varying levels of verbosity and being associated with the audio user interface event, wherein the varying levels of verbosity comprise a lowest level that includes no spoken words, a highest level that includes a plurality of spoken words, and a level therebetween that includes at least one spoken word and fewer spoken words than the highest level, determine a desired verbosity level, select from the set of audio items an audio item having a verbosity level corresponding to the desired verbosity level, and output the selected audio item to an audio output device. 
 
     
     
       29. The audio processing logic of  claim 28 , wherein the desired verbosity level is determined based upon at least one of a set of user preference settings or statistical data associated with the audio user interface event, wherein the user preference settings and the statistical data are stored in the one or more memory devices.

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates generally to user interfaces on electronic devices and, more particularly, to user interfaces capable of providing audio feedback to a user of an electronic device. 
     2. Description of Related Art 
     This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present techniques, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. 
     Electronic computing devices, such as computer systems, mobile phones, digital media players, personal digital assistants (PDAs), and the like, are commonly used for various personal and/or work-related purposes. Such electronic devices typically include some type of user interface that enables a user to interact with various applications (e.g., e-mail programs, internet browsers, media players, games, etc.) on the device to perform a variety of functions. In other words, the user interface may provide a gateway through which users may interact with applications to receive content, information, as well as responses to user inputs. The user interface, therefore, is an integral part in the design of these applications and helps determine the ease of use, and thus the quality of the overall user experience, of such devices. 
     Historically, many electronic devices have relied upon a graphical user interface to allow a user to interact with the device by way of a visual display. For instance, as the user interacts with the device, the device may display visual feedback in response to the user&#39;s actions. However, as some types of electronic devices have migrated towards smaller form factors having relatively small visual displays, graphical user interfaces are becoming not only more difficult to use and navigate, but also more limited in the amount of information they are able to convey. 
     More recently, audio user interfaces have experienced a rise in popularity. For instance, an audio user interface may supply audio feedback data, instead of or in addition to visual feedback, to convey information and content to a user and, thus, are particularly well suited for use in electronic devices having limited visual display capabilities or, in some instances, no visual display capabilities at all. For instance, upon the occurrence of an event that requests audio feedback, a corresponding audio clip may be played to convey audio information about the occurring event to the user. Unfortunately, some events may be associated with large amounts of audio information, which may overwhelm a user and, therefore, negatively impact the user experience, particularly when such events occur repeatedly in close proximity within a relatively short time period. Additionally, audio feedback provided by conventional audio user interfaces may not adequately enable a user to distinguish between events of high or low contextual importance. Accordingly, there are continuing efforts to further improve the user experience with respect to audio user interfaces in electronic devices. 
     SUMMARY 
     A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. 
     The present disclosure generally relates to techniques for adaptively varying audio feedback provided by an audio user interface on an electronic device. In accordance with one embodiment, an audio user interface may be configured to devolve or evolve the verbosity of audio feedback in response to user interface events based at least partially upon the verbosity level of audio feedback provided during previous occurrences of the user interface event. As will be discussed further below, the term “verbosity,” as used herein, refers to the “wordiness” of the audio information provided by the audio feedback, and may also encompass non-verbal types of audio feedback, such as tones, clicks, beeps, chirps, etc. For instance, if a subsequent occurrence of the user interface event occurs in relatively close proximity to a previous occurrence of the user interface event, the audio user interface may devolve the audio feedback (e.g., by reducing verbosity), such as to avoid overwhelming a user with repetitive and highly verbose information. 
     In another embodiment, an audio user interface may be configured to adaptively vary audio feedback associated with a navigable list of data items based at least partially upon the speed at which a user navigates the list. In a further embodiment, an audio user interface may be configured to provide audio feedback that is more audibly distinct to indicate where newer data content is located in the navigable list, and to provide audio feedback that is less audibly distinct for older data content. In yet another embodiment, an audio user interface may be configured to vary the verbosity and/or distinctiveness of the audio feedback based upon the contextual importance of a user interface event. The various audio feedback techniques disclosed herein, when implemented alone or in combination, may enhance the user experience with regard to audio user interfaces. 
     Various refinements of the features noted above may exist in relation to various aspects of the present disclosure. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. Again, the brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of embodiments of the present disclosure without limitation to the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which: 
         FIG. 1  is a block diagram of an electronic device that includes an audio user interface configured to adaptively vary audio feedback, in accordance with aspects of the present disclosure; 
         FIG. 2  is a front view of the electronic device of  FIG. 1  in the form of a desktop computing device, in accordance with aspects of the present disclosure; 
         FIG. 3  is a front view of the electronic device of  FIG. 1  in the form of a handheld portable electronic device, in accordance with aspects of the present disclosure; 
         FIG. 4  is a block diagram illustrating components that may be included in an audio user interface configured to adaptively vary audio feedback, in accordance with aspects of the present disclosure; 
         FIG. 5  is a screen image of an application that may be executed on the electronic device of  FIG. 1 ; 
         FIG. 6  is a screen image of the application shown in  FIG. 5  that depicts a visual notification of an event that occurs as a user interacts with the application, in accordance with aspects of the present disclosure; 
         FIG. 7  graphically depicts a set of audio items having varying levels of verbosity and being associated with the event depicted in  FIG. 6 , in accordance with aspects of the present disclosure; 
         FIGS. 8 and 9  are graphical timelines depicting how the verbosity of the audio feedback associated with the event of  FIG. 6  is varied over an interval of time in response to repeated occurrences of the event, in accordance with aspects of the present disclosure; 
         FIG. 10  is a screen image of the application shown in  FIG. 5 , further depicting an alternate visual notification of the event of  FIG. 6 , in accordance with aspects of the present disclosure; 
         FIG. 11A  is a flowchart depicting a first embodiment of a method for selecting an audio item for playback in response to the occurrence of an event requesting audio feedback, in accordance with aspects of the present disclosure; 
         FIG. 11B  is a flowchart depicting a second embodiment of a method for selecting an audio item for playback in response to the occurrence of an event requesting audio feedback, in accordance with aspects of the present disclosure; 
         FIG. 12  shows a plurality of screen images that may be displayed on the device of  FIG. 1  and illustrating how an audio user interface may provide audio feedback that distinguishes between events based upon contextual importance, in accordance with aspects of the present disclosure; 
         FIG. 13  is a flowchart depicting a method for selecting an audio item based upon the contextual importance of an event, in accordance with aspects of the present disclosure; 
         FIG. 14  depicts a plurality of screen images showing an application that may be executed on the electronic device of  FIG. 1  that includes a navigable list of items; 
         FIGS. 15-17  are screen images, each showing the navigable list of  FIG. 14  and depicting the navigation of the list by a user at varying speeds, in accordance with aspects of the present disclosure; 
         FIG. 18  is a flowchart depicting a method for varying audio feedback associated with the navigation of a list of items displayed on the electronic device of  FIG. 1  based upon a speed at which the list is navigated; and 
         FIGS. 19-21  are screen images that may be displayed on the device of  FIG. 1  illustrating various user-configurable options relating to varying audio feedback in an audio user interface, in accordance with aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     One or more specific embodiments of the present disclosure will be described below. These described embodiments are only examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. 
     As will be discussed below, the present disclosure relates generally to techniques for adaptively varying audio feedback provided by an audio user interface on an electronic device. As will be appreciated, an audio user interface may be particularly useful where an electronic device has either limited or no display capabilities. Further, even if the electronic device includes a visual display, there are times when a user may have difficulty navigating a graphical user interface, such as in “eyes-busy” situations where it is impractical to shift visual focus away from an important activity and towards the graphical user interface. Such activities may include, for example, driving an automobile, exercising, and crossing a busy street. Additionally, audio feedback is a practical substitute to visual feedback if the device is being used by a visually impaired user. 
     In accordance with one embodiment, an audio user interface may devolve or evolve the verbosity of audio feedback. As mentioned above, the term “verbosity,” as used herein, shall be understood to refer to the “wordiness” of the audio information provided by the audio feedback, and may encompass non-verbal types of audio feedback, such as clicks, beeps, chirps, or other various types of non-verbal sound effects. For example, audio feedback having a high level of verbosity may output several spoken words (e.g., playing a previously stored audio file containing the spoken words, or using text-to speech synthesis in real time), while audio feedback having a lower level of verbosity may output fewer spoken words or, in some cases, a non-verbal tone (e.g., no spoken words). In one embodiment, the verbosity of the audio feedback provided in response to user interface events is varied based at least partially upon the verbosity level of audio feedback provided during one or more previous occurrences of the user interface event. Thus, when subsequent occurrences of the user interface event occurs in relatively close proximity to a previous occurrence of the user interface event, the audio user interface may devolve the audio feedback (e.g., by reducing verbosity), such as to avoid overwhelming a user with repetitive and highly verbose information. 
     In another embodiment, an audio user interface may be configured to adaptively vary audio feedback associated with a navigable list of data items based at least partially upon the speed at which a user navigates the list. In a further embodiment, an audio user interface may be configured to provide audio feedback that is more audibly distinct to indicate where newer data content is located in the navigable list, and to provide audio feedback that is less audibly distinct for older data content. In yet another embodiment, an audio user interface may be configured to vary the verbosity and/or distinctiveness of the audio feedback based upon the contextual importance of a user interface event. The various audio feedback techniques disclosed herein, when implemented alone or in combination, may enhance the user experience with regard to audio user interfaces. 
     Before continuing, several additional terms used extensively throughout the present disclosure will be first defined in order to facilitate a better understanding of disclosed subject matter. For instance, events that occur during operation of an electronic device may be generally categorized as “user events” or “system events.” As used herein, the term “user event” and the like shall be understood to refer to an event that occurs as a result of a user&#39;s interaction with the device. To provide an example, a user event may be a notification indicating the availability of a particular device function requested by a user. In contrast, the term “system event” or the like shall be understood to events that are generally initiated by the device itself during operation to provide information pertaining to the status of the device, regardless of whether a user is actively interacting with or issuing requests and/or commands to the device. By way of example only, a system event may include a low battery notification. Thus, it should be understood the term “event,” as used herein, may refer to a user event or a system event, as defined above. 
     In the context of audio user interfaces, an electronic device may initiate the playback of an “audio item” to provide audio feedback upon the occurrence of certain events. As used herein, the term “audio item” or the like shall be understood to refer to audio information provided by an audio user interface of an electronic device. For instance, audio items may be an audio file stored on the device (e.g., in memory or non-volatile storage, and may contain verbal (e.g., speech data) audio information or non-verbal audio cues, such as beeps, clicks, chirps, chimes, rings, and other various tones or sound effects. Additionally, some audio items may not be stored locally on a device, but instead may be generated using synthesized speech applications (e.g., text-to-speech) in connection with an occurrence of a particular event that requests audio feedback. 
     In accordance with the techniques described below, certain events may be associated with a set of audio items having different verbosity levels. For instance, a set of audio items may include a non-verbal audio item (e.g., no wordiness content) and an audio item having a highest verbosity level (e.g., “full verbosity”), as well as one or more audio items of intermediate verbosity levels. As used herein, the terms “devolve,” “step down,” or the like, shall be understood to refer to the act of decreasing the verbosity of audio feedback associated with a particular event by selecting and playing back an audio item that is less verbose relative to the verbosity of the audio item selected during the previous occurrence of the event. Similarly, the term “evolve,” “step up,” or the like shall be understood to refer to the act of increasing the verbosity of audio feedback associated with a particular event by selecting and playing back an audio item that is more verbose relative to the verbosity of the audio item selected during the previous occurrence of the event. Various techniques for determining how to devolve or evolve audio feedback are disclosed below. 
     Further, the term “contextual importance” or the like, as applied to user interfaces, shall be understood to refer to the importance of the information provided in response to an event on a device relative to the context in which the information is provided. For instance, events of higher contextual importance may provide more distinct sounding audio feedback relative to events of lower contextual importance. To provide one example, events which may require a user response, such as an event prompting a user to allow or deny an incoming network connection, may have relatively high contextual importance, as the device may require the use to provide a decision in response to the event in order determine how to address the incoming network connection request. To provide another example, a first occurrence of a low battery warning notification event may have relatively low contextual importance, as such a notification is generally meant to be informative and does not necessarily require a user response or immediate user action. However, the contextual importance of a low battery notification may gradually increase if a user either intentionally or inadvertently disregards the low battery notification over several repeated occurrences, resulting in the device approaching a critical power threshold required for continued operation. 
     In other embodiments, the contextual importance of a user interface event may also be determined based upon pre-programmed information (e.g., events may be programmed as having high or low contextual importance characteristics). In other embodiments, the contextual importance of a user interface event may be adaptive or learned based upon previous device behavior and/or how a user interacts with the device during previous occurrence(s) of the user interface event. Additionally, in some embodiments, the contextual importance may be user-specified, such as via set of configurable user preference settings on the electronic device. Various embodiments are discussed for varying audio feedback to indicate contextual importance of events. Thus, it should be understood that the evolving and devolving of audio feedback verbosity may be an intelligent adaptive activity performed by an electronic device in response to user inputs (e.g., direct user inputs, user preference settings, etc.) and/or in response to external stimuli (e.g., device operation events—low power, low memory, etc.). Indeed, as will be shown in the various embodiments below, the evolution and devolution of audio feedback verbosity may be dynamic and may be tailored based on specific user preferences and/or settings stored on the device. 
     Turning now to the drawings,  FIG. 1  is a block diagram illustrating an example of an electronic device  10  that may include a user interface configured to vary audio feedback using one or more of the techniques briefly mentioned above. The electronic device  10  may be any type of electronic device, such as a laptop or desktop computer, a mobile phone, a digital media player, or the like, that includes an audio user interface configured to provide audio feedback using an audio output device. By way of example only, the electronic device  10  may be a desktop or laptop computer, such as a model of a MacBook®, MacBook® Pro, MacBook Air®, iMac®, Mac® Mini, or Mac Pro®, available from Apple Inc. of Cupertino, Calif. Additionally, the electronic device  10  may be a portable electronic device, such as a model of an iPod® or iPhone®, also available from Apple Inc. In other embodiments, the electronic device  10  may also be a model of an electronic device from another manufacturer that includes an audio user interface capable of providing audio feedback. 
     As shown in  FIG. 1 , the electronic device  10  may include various internal and/or external components which contribute to the function of the device  10 . Those of ordinary skill in the art will appreciate that the various functional blocks shown in  FIG. 1  may comprise hardware elements (including circuitry), software elements (including computer code, such as programs and/or firmware, stored on a computer-readable medium) or a combination of both hardware and software elements. For example, in the presently illustrated embodiment, the electronic device  10  may include the following components: input/output (I/O) ports  12 , input structures  14 , one or more processors  16 , memory device  18 , non-volatile storage device(s)  20 , display  22 , audio output device  24 , expansion card(s)  26 , networking device  28 , and power source  30 . Additionally, the electronic device  10  may also include a user interface  34  having both a graphical user interface  36  (a “GUI”) and an audio user interface  38 . As will be discussed further below, the audio user interface  38  may be configured implement one or more of the above-discussed techniques for varying audio feedback. 
     With regard to each of the illustrated components in  FIG. 1 , the I/O ports  12  may include various ports configured to connect to a variety of external devices, such as a power source, or other electronic devices (such as handheld devices and/or computers, printers, projectors, external displays, modems, docking stations, and so forth). The I/O ports  12  may support any interface type, such as a universal serial bus (USB) port, a video port, a serial connection port, an IEEE-1394 port, an Ethernet or modem port, and/or an AC/DC power connection port. In one embodiment, the I/O ports  12  may include a proprietary port from Apple Inc. that may function to charge the power source  30  (which may include one or more rechargeable batteries) of the device  10 , or to transfer data between the device  10  and an external source. Further, where the audio output device  24  includes an external audio output device (e.g., headphones or external speakers), the I/O ports  12  may include an audio connector port for connecting the audio output device  24  to the device  10 . 
     The input structures  14  may provide user input or feedback to the processor(s)  16 . For instance, the input structures  14  may be configured to control one or more functions of the electronic device  10 , such as applications running on the device  10 . By way of example only, the input structures  14  may include buttons, sliders, switches, control pads, keys, knobs, scroll wheels, keyboards, mice, touchpads, and so forth, or some combination thereof. In one embodiment, the input structures  14  may allow a user to navigate the GUI  36  displayed on the device  10 . Additionally, the input structures  14  may include a touch sensitive mechanism provided in conjunction with the display  22 . In such embodiments, a user may select or interact with displayed interface elements via the touch sensitive mechanism. 
     The operation of the device  10  may be generally controlled by one or more processors  16 , which may provide the processing capability required to execute an operating system, application programs, the GUI  36 , the audio user interface  38 , and any other functions provided on the device  10 . The processor(s)  16  may include a single processor or, in other embodiments, it may include multiple processors. By way of example, the processor  16  may include “general purpose” microprocessors, application-specific processors (ASICs), custom processors, or a combination of such processing components. For example, processor(s)  16  may include instruction set processors (e.g., RISC), graphics/video processors, audio processors, and/or other related chipsets. The processor(s)  16  may be coupled to one or more data buses for transferring data and instructions between various components of the device  10 . 
     Instructions or data to be processed by the processor(s)  16  may be stored in a computer readable medium, such as the memory  18 , which may be a volatile memory, such as random access memory (RAM), or as a non-volatile memory, such as read-only memory (ROM), or as a combination of RAM and ROM devices. For example, the memory  18  may store firmware for the device  10 , such as an operating system, applications, graphical and audio user interface functions, or any other routines that may be executed on the device  10 . While the user interface  34  (including the GUI  36  and audio user interface  38 ) are shown as being components of the memory  18 , it should be understood that the encoded instructions (e.g., machine-readable code) defining the GUI  36  and audio user interface  38  may actually reside in the non-volatile storage  20 , and may be loaded into the memory  18  for execution at run time. 
     The non-volatile storage device  20  may include flash memory, a hard drive, or any other optical, magnetic, and/or solid-state storage media, for persistent storage of data and/or instructions. By way of example, the non-volatile storage  20  may be used to store data files, including audio data, video data, pictures, as well as any other suitable data. As will be discussed further below, non-volatile storage  20  may be utilized by device  10  to store various audio items that may be selected and played back via the audio user interface  38  to provide audio feedback to a user of the device  10 . 
     The display  22  may be used to display various images generated by device  10 . For instance, the display  22  may receive and display images  40  generated by the GUI  36 . In various embodiments, the display  22  may be any suitable display, such as a liquid crystal display (LCD), plasma display, or an organic light emitting diode (OLED) display, for example. Additionally, the display  22  may be provided in conjunction with the above-discussed touch-sensitive mechanism (e.g., a touchscreen) that may function as part of a control interface for the device  10 . Further, it should be noted that in some embodiments, the device  10  may not include a display  22  or a GUI  36 , but instead may include only an audio user interface  38  through which a user interacts with the device  10 . An example of an embodiment of the device  10  that lacks a display  22  may be a model of an iPod® Shuffle, available from Apple Inc. 
     As mentioned above, the audio output device  24  may include an external audio output device, such as headphones or external speakers connected to the device  10  by an I/O port  12 . Additionally, the audio output device  24  may include integrated speakers. As shown in  FIG. 1 , audio feedback  42  provided by the audio user interface  38  may be played back using the audio output device  24 . In some embodiments, the audio user interface  38  may also be configured to receive audio inputs from a user (e.g., voice commands) by way of an audio input device (now shown in  FIG. 1 ), which may be translated into instructions or commands for performing a certain task or function on the device  10 . 
     The embodiment illustrated in  FIG. 1  may also include one or more card or expansion slots. The card slots may be configured to receive one or more expansion cards  26  that may be used to add functionality, such as additional memory, I/O functionality, or networking capability, to the electronic device  10 . Such an expansion card  26  may connect to the device  10  through any type of suitable connector, and may be accessed internally or external with respect to a housing of the electronic device  10 . For example, in one embodiment, the expansion card(s)  26  may include a flash memory card, such as a SecureDigital (SD) card, CompactFlash card, Multimedia card (MMC), or the like, or a PCMCIA device. Additionally, the expansion card  24  may be a Subscriber Identity Module (SIM) card, for use with an embodiment of the electronic device  10  that provides mobile phone capability. 
     The electronic device  10  also includes the network device  28 , which may be a network controller or a network interface card (NIC) that may provide for network connectivity over a wireless 802.11 standard or any other suitable networking standard, such as a local area network (LAN), a wide area network (WAN), such as an Enhanced Data Rates for GSM Evolution (EDGE) network, a 3G data network, or the Internet. By way of the network device  28 , the device  10  may connect to and send or receive data with any device on the network, such as portable electronic devices, personal computers, printers, and so forth. In certain embodiments, the network device  28  may provide for a connection to an online digital media content provider, such as the iTunes® service, available from Apple Inc. 
     The power source  30  of the device  10  may include the capability to power the device  10  in both non-portable and portable settings. For example, in a portable setting, the device  10  may include one or more batteries, such as a Li-Ion battery, for powering the device  10 . The battery may be recharged by connecting the device  10  to an external power source, such as to an electrical wall outlet. In a non-portable setting, the power source  30  may include a power supply unit (PSU) configured to draw power from an electrical wall outlet, and to distribute the power to various components of a non-portable electronic device, such as a desktop computing system. 
     Having described the components of the electronic device  10  depicted in  FIG. 1 ,  FIGS. 2 and 3  illustrate various forms that the electronic device  10  may take. As shown in  FIG. 2 , the electronic device  10  may take the form of a computing system  50 . The depicted computer  50  includes a housing  52 , the display  22 , input structures  14  in the form of a keyboard and mouse, as well as an audio output device  24  in the form of integrated speakers. The computer  50  further includes an integrated imaging device  54 , such as a digital camera. While the illustrated computer  50  is shown as being a generally non-portable computer system (e.g., desktop computer, workstation, and/or server), it should be understood that the computer  50  may also be provided using smaller and more portable form factors (e.g., laptop computers, net-book computers, and/or tablet computers). 
     As will be appreciated, the input structures  14  may also include various other buttons and/or switches which may be used to interact with the computer  50 , such as to power on or start the computer, to operate a GUI or an application running on the computer  50 , as well as adjust various other aspects relating to operation of the computer  50  (e.g., sound volume, display brightness, etc.). The computer  50  may also include various I/O ports  12  that provide for connectivity to additional devices, as discussed above, such as a FireWire® or USB port, a high definition multimedia interface (HDMI) port, or any other type of port that is suitable for connecting to an external device. Additionally, the computer  50  may include network connectivity (e.g., network device  28 ), memory (e.g., memory  18 ), and storage capabilities (e.g., storage device  20 ), as described above with respect to  FIG. 1 . 
     As further shown, the display  22  may be configured to generate various images that may be viewed by a user. For example, during operation of the computer  50 , the display  28  may display the GUI  36  that allows the user to interact with an operating system and/or applications running on the computer  50 . The GUI  36  may include various layers, windows, screens, templates, or other graphical elements that may be displayed in all, or a portion, of the display device  22 . For instance, in the depicted embodiment, the GUI  36  may display an operating system interface that includes various graphical icons  56 , each of which may correspond to various applications that may be opened or executed upon detecting a user selection (e.g., via keyboard/mouse or touchscreen input). The icons  56  may be displayed in a dock  58  or within one or more graphical window elements  60  displayed on the screen. 
     In some embodiments, the selection of an icon  56  may lead to a hierarchical navigation process, such that selection of an icon  56  leads to a screen or opens another graphical window that includes one or more additional icons or other GUI elements. By way of example only, the operating system GUI  36  displayed in  FIG. 2  may be from a version of the Mac OS® operating system, available from Apple Inc. Additionally, the computer  50  may also include an audio user interface (e.g.,  38 ) running concurrently with the GUI  36 . For instance, in response to user events or system events, the audio user interface  38  may provide audio feedback to the user through the audio output devices  24 . By way of example only, an embodiment of the audio user interface  38  may be the VoiceOver® utility, available on versions of the Mac OS® operating system, as well as on certain models of iPods® and iPhones®, all available from Apple Inc. 
       FIG. 3  further illustrates the electronic device  10  in the form of portable handheld electronic device  70 , which may be a model of an iPod® or iPhone® available from Apple Inc. In the depicted embodiment, the handheld device  70  includes an enclosure  52 , which may function to protect the interior components from physical damage and to shield them from electromagnetic interference. The enclosure  52  may be formed from any suitable material or combination of materials, such as plastic, metal, or a composite material, and may allow wireless networking signals, to pass through to wireless communication circuitry (e.g., network device  28 ), which may be disposed within the enclosure  52 , as shown in  FIG. 3 . 
     The enclosure  52  also includes various user input structures  14  through which a user may interface with the handheld device  70 . For instance, each input structure  14  may be configured to control one or more respective device functions when pressed or actuated. By way of example, one or more of the input structures  14  may be configured to invoke a “home” screen  72  or menu to be displayed, to toggle between a sleep, wake, or powered on/off mode, to silence a ringer for a cellular phone application, to increase or decrease a volume output, and so forth. It should be understood that the illustrated input structures  14  are merely exemplary, and that the handheld device  70  may include any number of suitable user input structures existing in various forms including buttons, switches, keys, knobs, scroll wheels, and so forth. 
     As shown in  FIG. 3 , the handheld device  70  may include various I/O ports  12 . For instance, the depicted I/O ports  12  may include a proprietary connection port  12   a  for transmitting and receiving data files or for charging a power source  26  and an audio connection port  12   b  for connecting the device  70  to an external audio output device  24  (e.g., headphones or speakers). Further, in embodiments where the handheld device  70  provides mobile phone functionality, the device  70  may include an I/O port  12   c  for receiving a subscriber identify module (SIM) card (e.g., an expansion card  26 ). 
     The display device  22  may display various images generated by the handheld device  70 . For example, the display  22  may display various system indicators  73  providing feedback to a user with regard to one or more states of handheld device  70 , such as power status, signal strength, external device connections, and so forth. The display  22  may also display the GUI  36  that allows a user to interact with the device  70 , as discussed above with reference to  FIG. 2 . The GUI  36  may include icons  56  which may correspond to various applications that may be opened or executed upon detecting a user selection of a respective icon  56 . For instance, the icon  74  may represent a media player application, the icon  76  may represent an online digital media service application, and the icon  78  may represent an application through which a user may configure one or more settings of the device  70 . By way of example only, the displayed GUI  36  of  FIG. 3  may be from a version of the iPhone® OS operating system, available from Apple Inc. 
     The handheld device  70  also includes the audio output devices  24 , the audio input devices  80 , as well as the output transmitter  82 . As discussed above, an audio user interface  38  on the device  70  may use the audio output devices  24  to provide audio feedback to a user through the playback of various audio items. Additionally, the audio output device  24  may be utilized in conjunction with the media player application  76 , such as for playing back music and media files. Further, where the electronic device  70  includes a mobile phone application, the audio input devices  80  and the output transmitter  82  may operate in conjunction to function as the audio receiving and transmitting elements of a telephone. 
     Referring now to  FIG. 4 , a block diagram depicting functional components of an audio user interface  38  that may be implemented in the device  10  of  FIG. 1  is illustrated in accordance with one embodiment. The audio user interface  38  includes audio feedback selection logic  86  that receives data  88  indicating the occurrence of an event, such as a user or system event. Upon receiving the data  88 , the audio feedback selection logic  86  may communicate with an event statistics data storage unit  92  and an audio feedback data storage unit  94  (both of which may be part of the non-volatile storage  20  ( FIG. 1 ) or implemented as standalone storage devices) as well as a set of user preferences  96  and a clock or timer  98 , to determine the selection of an audio item  100  for playback using the audio output device  24 . As will be appreciated, the functions provided by the various components shown in  FIG. 4  may be executed or performed by one or more processors  16  of the electronic device  10 . 
     For example, as mentioned above, one aspect of the audio feedback selection logic  86  may relate to devolving or evolving audio feedback in response to an event  88 . In one embodiment, the selection logic  86  may identify a set of audio items (“audio feedback data set”) within the audio data storage  94  that is associated with the event  88  as being candidates for audio feedback. As discussed above, the set of audio items corresponding to the event  88  may vary in levels of verbosity, wherein each level may be referred to as a “step.” Thus, as defined above, “stepping down” the audio feedback may refer to decreasing the verbosity of the audio feedback, while “stepping up” the audio feedback may refer to increasing the verbosity of the audio feedback. Accordingly, an audio item  100  corresponding to a desired level of verbosity may be selected in accordance with information provided by the event statistics data storage  92  and the user preferences  96 . 
     In one embodiment, the event statistics data storage  92  may store information about the event  88 , including the frequency at which event  88  has previously occurred during operation of the device  10 , the audio item selected for playback during the most recent occurrence of the event  88 , as well as the temporal proximity at which the event  88  last occurred, and so forth. By way of example, each previous occurrence of the event  88  may be stamped with a time value provided by the timer  98  and stored as a data entry in the event statistics data storage  92 . The timer  98  may be implemented as a standalone clock (e.g., an RC oscillator) or may be configured to derive time values based on an external system clock of the device  10 . Thus, when the event  88  occurs in close proximity, i.e., within a selected amount of time (a “wait time” or “step-up time” configurable through the user preferences  96 ), relative to the previous occurrence of the event  88 , the audio feedback selection logic  86  may select an audio item  100  from the audio feedback data set that is less verbose relative to the audio item selected during the previous occurrence. In this manner, the audio user interface  38  may avoid repeatedly playing back the same high verbosity audio item for multiple occurrences of a particular event  88  over a relatively short amount of time, thus improving the user experience with regard to the audio user interface  38 . 
     By the same token, some embodiments of the audio feedback selection logic  86  may also be configured to evolve the audio feedback using a technique similar to the devolving process discussed above. For example, upon detecting the occurrence of the event  88 , if the event statistics data  92  indicates that the event  88  has not occurred within the interval corresponding to the selected step-up time just prior to the occurrence of the event  88 , then the selection logic  86  may evolve the audio feedback by selecting an audio item  100  from the audio feedback data set that is more verbose relative to the audio item selected for the previous occurrence of the event  88 . 
     While the frequency and temporal proximity in which an event  88  occurs is one metric by which the selection logic  86  of the audio user interface  38  may vary audio feedback, other factors may also contribute to how the selection logic  86  selects the audio item  100 . For instance, in one embodiment, the selection logic  86  may be configured to control or vary audio feedback based upon the contextual importance of the event  88 , which may depend upon the relative importance of the information provided in response to the event  88  relative to the context in which the event  88  occurred. In other embodiments, contextual importance of an event may be determined based upon pre-programmed information (e.g., events may be programmed as having high or low contextual importance characteristics), may be adaptive or learned based upon previous device behavior and/or how a user interacts with the device during previous occurrence(s) of the event, or may be user-specified, such as via set of configurable user preference settings on the electronic device, or may be determined based on a combination of such factors. In a further embodiment, the selection logic  86  may be configured to vary audio feedback associated with a displayed list of items based upon the speed at which the list is navigated by a user of the device  10 . 
     With these points in mind, the remaining figures are intended to depict various embodiments for varying audio feedback provided by an audio user interface (e.g.,  38 ) in accordance with aspects of the present disclosure. Specifically,  FIGS. 5-11  depict embodiments in which the audio feedback selection logic  86  is configured to vary audio feedback based upon the proximity in which an event occurs on the device  10  relative to previous occurrences of the same event.  FIGS. 12-13  depict an embodiment in which the selection logic  86  is configured to vary audio feedback based on the contextual importance of an event occurring on the device  10 .  FIGS. 14-18  depict an embodiment in which the selection logic  86  is configured to vary audio feedback based on the manner in which a user navigates a listing of items displayed on the device  10 . Finally,  FIGS. 19-21  depict an embodiment of a configuration application through which a user may define and/or configure various audio user interface settings relating to varying audio feedback on the device  10 . Those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is merely intended to provide, by way of example, certain forms that embodiments of the invention may take. That is, the disclosure should not be construed as being limited only to the specific embodiments discussed herein. 
     Referring to  FIG. 5 , a screen image  104  depicting an application  106  on the device  10  is illustrated in accordance with one embodiment. The screen image  104  may be part of a graphical user interface for the application  106 , and may be displayed using the display  22  on the computer  50  of  FIG. 2 . In the depicted embodiment, the application  106  may be a digital media player application, such as the iTunes® application, available from Apple Inc., and may be initiated when a user selects an appropriate icon  56  from an operating system GUI  36 , as shown in  FIG. 2 . For the purposes of the embodiments discussed below, it should be understood that the application  106  either includes an audio user interface (e.g.,  38 ) or is compatible with a global audio user interface (e.g., of a main operating system of the device  10 ) to provide audio feedback to the user. 
     As discussed above, a GUI  36 , depending on the inputs and selections made by a user, may display various screens including icons (e.g.,  56 ) and graphical elements. These elements may represent graphical and virtual elements or “buttons” which may be selected by the user from the display  22  using one or more input structures  14  ( FIG. 1 ). Accordingly, it should be understood that the term “button,” “virtual button,” “graphical button,” “graphical elements,” or the like, as used in the following description of screen images below, is meant to refer to the graphical representations of buttons or icons represented by the graphical elements provided on the display  22 . Further, it should also be understood that the functionalities set forth and described in the subsequent figures may be achieved using a wide variety graphical elements and visual schemes. Therefore, the present disclosure is not intended to be limited to the precise user interface conventions depicted herein. Rather, the embodiments set forth herein may be implemented include a wide variety of user interface styles. 
     As shown in the screen  104 , the application  106  may display a list  108  of media items  110 , such as song files, video files, podcasts, and so forth, from which a user may select an item  112  for playback on the device  10 . As shown in  FIG. 5 , the list  108  may display various characteristics about each media item  110 , such as a song name, track playback time, artist name, album name, and genre. Once a selected item  112  is identified, the user may initiate playback of the selected item  112  by selecting a graphical playback button  114 . Additionally, the user may return to a previously played item by selecting the graphical button  116 , skip forward to another item in the list  108  by selecting the graphical button  118 , or adjust the playback volume of the selected item  112  by manipulating the graphical sliding bar  120 . As shown here, the screen  104  also includes the scroll bar elements  122  and  124 , which may allow a user to navigate the entire list  108  vertically and horizontally if the size of the display  22  is insufficient to display the list  108  in its entirety. 
     Additional playback functions provided by the application  106  are depicted by the graphical buttons  126 ,  128 ,  130 , and  132 . For instance, the graphical button  126  may represent a function by which the user may manually create a new group of media items for playback, commonly referred to as a “playlist.” The graphical buttons  128  and  130  may represent functions for enabling or disabling “shuffle” and “repeat” playback modes, respectively. Finally, the graphical button  132  may represent a function for automatically generating a playlist using media items stored on the device  10  which are determined to be similar to the selected media item  112 . By way of example only, such a function may be provided as the Genius® function, available on the iTunes® application, as well as on models of the iPod® and iPhone®, all available from Apple Inc. 
     Genius® playlists may be generated using ratings system and filtering algorithms provided through an external centralized server, such as the iTunes® server, provided by Apple Inc. In some instances, however, the Genius® function may be unable to fulfill a user request for generating a playlists, such as when a selected media item  112  is relatively new and the Genius® function is unable to obtain sufficient data points for identifying similar media stored on the device  10  (e.g., in non-volatile storage  20 ). Additionally, the Genius® function may also be unavailable if the total number of media items stored on the device  10  is insufficient to generate a suitable playlist. For the purposes of the embodiments discussed below with respect to  FIGS. 6-10 , the selection of the Genius® button  132  is used as an example of an event  88  ( FIG. 4 ) that triggers or requests audio feedback. 
       FIG. 6  shows an updated view of the screen  104  following the selection of the Genius® button  132 . In the illustrated example, it is assumed that the Genius® function is unavailable for the selected media item  112 . In response to this event  88 , the graphical user interface  36  portion of the application  106  may display the visual notification window  140 , which contains a visual notification  142  informing the user that the requested function is unavailable. Generally concurrent with the display of the visual notification window  140 , the audio user interface  38  portion of the application  106  may provide audio feedback to inform the user that the requested function is unavailable. For instance, audio feedback may be provided by playing back an audio item, which may include playing an audio file or using a using a text-to-speech application to “speak” the notification  142  using synthesized speech. In order to remove the visual notification window  140  from the screen  104 , the user may select the graphical button  144 , which may indicate to the device  10  and application  106  that the user has received and acknowledged the information conveyed by the visual notification window  140 . 
     As discussed above, certain embodiments of the present technique may include devolving audio feedback in response to the event  88 . For instance, suppose that after attempting to apply the Genius® function to the selected media item  112 , the user further attempts to apply the Genius® function to several other items on the list  108  within a relatively short interval of time with no success, thus triggering the event  88  on each attempt. Assuming that the devolving techniques discussed above are not applied, audio feedback would be provided at “full-verbosity” for each occurrence, which may overwhelm the user with repetitive information and, thus, negatively impact the user experience with regard to the application  106 . 
     To enhance the user experience, the audio feedback selection logic  86  ( FIG. 4 ) may reduce the verbosity of the audio feedback corresponding to the event  88  by analyzing event statistics data (e.g., from storage  92 ) relating to the event  88  and selecting an appropriate audio item from an audio feedback data set associated with the event  88 . Referring now to  FIG. 7 , an example of an audio feedback data set  148  is illustrated. As shown, the audio feedback data set  148  may include the audio items  150 ,  152 ,  154 , and  156 , each having varying degrees of verbosity. For instance, the audio item  150 , referred to as “full verbosity,” is the most verbose and, when selected by the selection logic  86 , may cause the verbal audio information “GENIUS IS CURRENTLY UNAVAILABLE FOR THIS TRACK” to be played back through the audio output device  24 , generally concurrently with the display of the visual notification window  140  of  FIG. 6 . 
     The audio item  152  may represent a first-level devolved audio item that is less verbose relative to the audio item  150 , but still contains a substantial portion of verbal audio information. For instance, when selected, the audio item  152  may cause the verbal audio information “GENIUS IS NOT AVAILABLE” to be played back through the audio output device  24 . The audio item  154  is even less verbose compared to the audio item  152 , and only includes a relatively short verbal message: “NO GENIUS.” Finally, the audio item  156  represents the least verbose item of the set  148 , and includes no verbal components, but only a non-verbal cue in the form of a negative sounding tone or beep. 
     Thus, the depicted audio feedback data set  148  of  FIG. 7  illustrates represents audio items (e.g.,  150 ,  152 ,  154 , and  156 ) having varying levels or steps of verbosity from which the selection logic  86  may select to either evolve or devolve the audio feedback corresponding to the occurrence of the event  88 . Further, while the present embodiment illustrates an audio feedback data set having 4 steps of verbosity, it should be understood that in other embodiments or with respect to other events, a corresponding audio feedback data sets may include fewer or more steps of verbosity. Further, some embodiments may provide an audio feedback data set that includes multiple audio items for the same level of verbosity. For instance, as will be discussed further below, in one embodiment, different non-verbal cues may be provided to help a user determine the contextual importance of a particular event. 
     An example illustrating how audio feedback corresponding to the event  88  shown in  FIG. 6  may be devolved and evolved over a period of time is illustrated in  FIG. 8  by way of a graphical timeline depicting the operation of the device  10  over a period of 120 minutes. As shown, the event  88  may occur multiple times within this period, specifically at times t 0  (0 minutes), t 20  (20 minutes), t 35  (35 minutes), t 55  (55 minutes), and t 110  (110 minutes). While the event  88  is generally identical at each of these times, in order to better distinguish each occurrence, the events have been labeled with the reference numbers  88   a ,  88   b ,  88   c ,  88   d , and  88   e . The present example assumes a step-up time interval set at 45 minutes, which may be preset by the manufacturer of the device  10  or programmer of the user interface  34 , or later configured by the user (e.g., via the user preferences  96  shown in  FIG. 4 ), and further assumes that in the step-up time interval just prior to time t 0  (e.g., the previous 45 minutes from −t 45  to t 0 ), the event  88  did not occur. 
     Beginning at time t 0 , the occurrence of the event  88   a  may result in the visual notification window  140  of  FIG. 6  being displayed on the screen  104 , as well as the selection and playback of the full verbosity audio item  150 . For instance, the event statistics data storage unit  92  may indicate to the selection logic  86  that no similar events  88  occurred within the step-up time interval (45 minutes) just prior to time t 0 . Based on this data, the selection logic  86  may select and initiate the playback of the full verbosity audio item  150  to provide audio information substantially concurrently with the display of visual information (e.g., visual notification window  140 ) relating to the occurrence of the event  88   a . Upon initiating the playback of the audio item  150 , the audio user interface  38  may utilize the timer  98  to establish a step-up window  157  from time t 0  to time t 45 . If the event  88  occurs again within this window  157 , the selection logic  86  may devolve the audio feedback. 
     In the present example, the event  88   b  occurs once again at time t 20 . Upon the occurrence of the event  88   b , the event statistics data storage unit  92  may indicate to the selection logic  86  that the event  88   a  occurred less than 45 minutes ago (e.g., the step-up interval). Thus, because the event  88   b  occurs within the step-up window  157  (e.g., from t 0  to t 45 ), the selection logic  86  may identify the audio item that was played during the most recent occurrence of the event  88  (e.g., in this case, audio item  150  at time t 0 ), and devolve the audio feedback by one step of verbosity. This may result in the selection and playback of the audio item  152 , which, as shown in  FIG. 7 , is one verbosity step less relative to the audio item  150 . Once the playback of the audio item  152  occurs at time t 20 , the remainder of the step-up window  157  becomes irrelevant, and a new “current” step-up window  158  is established from time t 20  to time t 65 . 
     Thereafter, the event  88   c  occurs again at time t 35 . Because the event  88   c  occurs within the step-up window  158  (e.g., from t 20  to t 65 ), the selection logic  86  of the audio user interface  38  may further devolve the audio feedback associated with the event  88   c  by selecting and playing back the audio item  154 , which is one verbosity step lower than the previously played audio item  152 . Once the playback of the audio item  154  occurs at time t 35 , the remainder of the step-up window  158  also becomes irrelevant, and a step-up window  159  associated with the event  88   c  is established from time t 35  to time t 80  and becomes the current step-up window. 
     Following the event  88   c , the event  88   d  occurs again at time t 55 . Again, because the event  88   d  occurs within the current step-up window  159  (e.g., from t 35  to t 80 ), the selection logic  86  of the audio user interface  38  may lower the verbosity of the audio feedback an additional step, thus fully devolving the audio feedback associated with the event  88  to the non-verbal audio item  156 . Thereafter, once the playback of the non-verbal audio item  156  occurs at time t 55 , a new step-up window  160  associated with the event  88   d  is established from time t 55  to time t 100 , and the remainder of the previous step-up window  159  becomes irrelevant. In other words, as long as the event  88  continues to occur within a current step-up time window following the most recent previous occurrence of the event  88 , the selection logic  86  may continue to devolve the audio feedback corresponding to the event  88 . It should be noted, however, that because the audio item  156  cannot be devolved any further in the present example, additional occurrences of the event  88  within the window  160  may result in the selection logic  86  selecting and playing the audio item  156  again. 
     Next, at time t 110 , the event  88   e  occurs once again. This occurrence, however, is outside of the step-up window  160 . In this case, the selection logic  86  may be configured to evolve the audio feedback. For instance, in one embodiment, the selection logic  86  may “reset” the verbosity of the audio feedback to full verbosity by selecting and playing back the audio item  150  at time  110 , regardless of the verbosity level of the most recently played audio item (e.g., audio item  156 ). In another embodiment, the selection logic  86  may evolve the audio feedback by increasing the verbosity of the audio feedback by one step relative to the most recently played audio item. For instance, in the present example, the selection of the audio item  154  at time t 110  may provide a one step increase in the verbosity of the audio feedback relative to the most recently played audio item  156 . 
     As will be appreciated, the occurrence of each of the events  88   a - 88   e , in addition to triggering audio feedback, may also trigger the display of visual feedback on the GUI  36 , such as by way of the visual notification window  140  shown in  FIG. 6 . Further, the occurrence of each of the events  88   a - 88   e  may be stored in the event statistics data storage  92  to provide statistical data which may be used by the audio feedback selection logic  86  when determining the appropriate audio feedback for future occurrences of the event  88 . 
     While the graphical timeline depicted in  FIG. 8  illustrates a constant rate of devolvement (e.g., one step of verbosity) for each subsequent occurrence of the event  88  that occurs within a current step-up window, other embodiments of the present techniques may vary the rate at which audio feedback is devolved based not only upon the proximity in which the event  88  occurs relative to a previous occurrence, but also based at least partially upon the user&#39;s reaction or response to visual feedback and/or audio feedback resulting from the event  88 . 
     For instance, one embodiment for devolving audio feedback may consider the occurrence of a “playback termination event.” As used herein, a playback termination event refers to a response by the user that terminates the playback of an audio item before completion. For instance, referring to  FIG. 6 , in one embodiment, the user may select the graphical button  144  during but prior to the completion of the playback of a selected audio feedback item (e.g., one of the audio items  150 ,  152 ,  154 , and  156 ) to cause a playback termination event. A playback termination event may also be communicated to the device  10  using other actions, such as a gesture-based action (e.g., gently shaking the device  10 ). Accordingly, the device  10  may interpret playback termination events as a response that the user is not interested in the information provided by either or both the visual notification window  140  and the selected audio feedback. 
     An example illustrating how playback termination events may affect the devolvement of audio feedback is shown in  FIG. 9  by way of a graphical timeline depicting the operation of the device  10  over a period of 120 minutes, in which the event  88  occurs at times t 0 , t 30 , and t 110 . For distinguishing purposes, these occurrences are referred to by the reference numbers  88   f ,  88   g , and  88   h . Additionally, for the purposes of the example shown in  FIG. 9 , a 45 minute step-up interval is assumed. It is also assumed that the event  88  did not occur in the step-up time interval just prior to time t 0  (e.g., the previous 45 minutes from −t 45  to t 0 ). 
     Beginning at time t 0 , the occurrence of the event  88   f  may result in the visual notification window  140  of  FIG. 6  being displayed on the screen  104 , as well as the selection and playback of the full verbosity audio item  150  at time t 0 . During the playback of the audio item  150 , a playback termination event  161  is detected, which may cause the playback of the audio item  150  to prematurely terminate. For example, this may be the result of the user selecting the graphical button  144  prior to the complete playback of the audio item  150 , or may be the result of a termination gesture (e.g., shaking the device  10 ), or any other type of action that terminates the playback of the audio item  150  prior to its completion. The occurrence of the event  88   f , as well as the playback termination event  161 , is stored into the event statistics data storage  92 . Additionally, a step-up window  162  for detecting subsequent occurrences of the event  88  is established from time t 0  to time t 45   
     Next, the event  88   g  occurs again at time t 30 . Upon the occurrence of the event  88   g , the event statistics data storage unit  92  may indicate to the selection logic  86  that a playback termination event  161  was detected in connection with the previous occurrence of the event  88   f  at time t 0 . In the illustrated embodiment, this may cause the selection logic  86  to fully devolve the audio feedback by selecting and playing back the non-verbal audio item  156 , thus bypassing the verbosity levels represented by the audio items  152  and  154 . A new step-up window  163  is established from time t 30  to time t 75 . As will be appreciated, like the embodiment of  FIG. 8 , subsequent occurrences of the event  88  within the window  163  may result in the audio item  156  being played again, and subsequent occurrences of the event  88  outside of the window  163  may result in the audio feedback being reset to full verbosity (e.g., audio item  150 ), as shown in  FIG. 9  at time t 110 . 
     In some embodiments, a playback termination event (e.g.,  161 ) may, in addition to affecting audio feedback behavior, also affect visual feedback behavior. For instance, referring to  FIG. 10 , the screen  104  is depicted during the occurrence of the event  88   g  at time t 30  of  FIG. 9 . As shown, due the detection of the playback termination event  161  during the most recent occurrence of the event (e.g.,  88   f  at time t 0 ), the visual notification window  140  that previously appeared in the center of the screen  104  in  FIG. 6  is devolved into a less prominent and smaller notification banner  164  that appears near the upper right corner of the screen  104 . The notification banner  164  includes the visual notification message  165 , which is also devolved relative to the more verbose notification message  142  shown in  FIG. 6 . 
     The notification banner  164  may include the graphical elements  166  and  168 . By selecting the graphical element  166 , the user may expand the notification banner  164 , causing the window  140  to appear instead. In one embodiment, the GUI  36  may display the notification banner  164  only briefly, such as for a period of 5 to 10 seconds, before automatically removing the banner  164  from the screen  104 . Additionally, the user may choose to manually remove the notification banner  164  by selecting the graphical button  168 . 
     The various techniques for devolving and evolving audio feedback, as described with reference to the embodiments shown in  FIGS. 5-10 , are generally summarized by the method  169  depicted by the flowchart of  FIG. 11A , and the method  174 , depicted by the flowchart shown in  FIG. 11B . 
     Referring first to  FIG. 11A , the method  169  illustrates a more basic approach for providing evolving/devolving audio feedback based on a desired verbosity level. For instance, the method  169  begins at step  170 , at which the occurrence of an event at a first time (T(x)) (e.g., an indication that the Genius® function of  FIG. 6  is unavailable) triggering or requesting audio feedback is detected by the audio user interface  38  of the device  10 . Next, at step  171 , a set of audio items corresponding to the detected event is identified, whereby each of the audio items within the set may have a different level of verbosity with respect to every other audio items within the set. 
     Thereafter, at step  172 , a first audio item is selected that corresponds to a desired verbosity level which, as shown in  FIG. 11A , may be determined based at least partially upon whether the detected event from step  170  occurred within a particular time interval (e.g., a step-up window) prior to the time T(x). In one embodiment, if the event previously occurred within the particular time interval, then the desired verbosity level may be devolved in relation to the verbosity of the audio item selected during the immediately preceding occurrence of the event. Similarly, if the event did not previously occur within the particular time interval, then the desired verbosity level may be evolved in relation to the verbosity of the audio item selected during the immediately preceding occurrence of the event. Subsequently, at step  173 , the selected audio item (e.g., having the desired verbosity level) is played back to provide audio feedback in response to the detected event. 
       FIG. 11B  illustrates a more detailed flowchart that depicts additional features, as discussed above with reference to  FIGS. 8-9 . For instance, the method  174  begins at step  175 , at which the occurrence of an event (e.g., an indication that the Genius® function of  FIG. 6  is unavailable) triggering or requesting audio feedback is detected by the audio user interface  38  of the device  10 . Next, at step  176 , a set of event statistics data and an audio feedback data set, which may include multiple audio items having different levels of verbosity, that correspond to the event detected at step  175  are identified. 
     Based upon the event statistics data from step  176 , the selection logic  86  may, at decision block  177 , determine whether the event occurred within the step-up window following the most recent previous occurrence of the event. If the event did not occur within the step-up window, then the method  174  continues to step  178 , whereby audio feedback is provided at full verbosity. As mentioned above, in an alternate embodiment, rather than providing full verbosity, the selection logic  86  may instead evolve the audio feedback by one step. For instance, as shown in  FIG. 11 , if the event did not occur within the step-up window, the method  174  may alternatively continue to step  180 , at which the most recently selected audio item corresponding to the most recent previous occurrence of the event is identified, and step  182 , at which the audio feedback is evolved by one step relative to the previously selected audio item and played back by the device  10 . 
     Referring again to decision block  177 , if the event does occur within the step-up window following the previous occurrence, the method  174  continues to decision block  186 , at which a determination is made as to whether the previous occurrence was accompanied by a playback termination event (e.g.,  161 ). If a playback termination event was detected alongside the previous occurrence of the event, the method  174  continues to step  188 , and the most devolved audio item from the audio feedback data set (e.g.,  148 ) is selected and played back. By way of example, the most devolved audio item may be a non-verbal audio cue (e.g., audio item  156 ). 
     If the decision block  186  determines that there was not a playback termination event detected during the previous occurrence of the event, then the most recently selected audio item corresponding to the previous occurrence of the event is identified at step  190 . At step  192 , a determination is made as to whether the most recently selected audio item is already the most devolved audio item of the audio feedback data set from step  176 . If the most recently selected audio item is determined to be the most devolved audio item from the set, then it is selected as the current audio item and played back at step  188 . If the most recently selected audio item is not the most devolved audio item from the set, then the selection logic  86  may devolve the audio feedback one step, and play the corresponding devolved audio item. 
     Continuing to  FIGS. 12 and 13 , embodiments illustrating how audio feedback may be varied based upon the contextual importance of an event are illustrated in accordance with aspects of the present disclosure. As defined above, the contextual importance refers to the importance of the information provided in response to an event on a device relative to the context in which the information is provided. 
     Referring first to  FIG. 12 , a series of screen images depicting the occurrence of two different events having differing contextual importance characteristics is illustrated. The screen images shown in  FIG. 12  may be part of the GUI  36  displayed on the handheld device  70  shown in  FIG. 3 . For instance, beginning from the home screen  72  of the GUI  36 , the user may initiate a media player application by selecting the icon  74 . By way of example, the media player application  74  may be an iPod® application running on a model of an iPod Touch® or an iPhone®, available from Apple Inc. Additionally, the GUI  36 , as shown in  FIG. 12 , may be a version of an iPod® or iPhone® operating system, also available from Apple Inc. 
     Upon selection of the icon  74 , the user may be navigated to a home screen  200  of the media player application  74 . As shown in  FIG. 12 , the screen  200  may initially display a listing  202  of playlists  204 , each of which may include a plurality of media files defined by the user. For instance, a playlist  204  may constitute all the song files from an entire music album, or may be a custom “mix” of media files chosen by the user of the device  10 . The screen  200  also includes the graphical buttons  206 ,  208 ,  210 ,  212 , and  214 , each of which may correspond to specific functions. For example, if the user navigates away from the screen  200 , the selection of the graphical button  206  may return the user to the screen  200 . The graphical button  208  may organize the media files stored on the device  10  alphabetically based on the names of artists associated with each media file. The graphical button  210  may represent a function by which the media files corresponding specifically to music (e.g., song files) are sorted and displayed on the device  10 . For instance, the selection of the graphical button  210  may display all music files stored on the device  10  alphabetically in a listing that may be navigated by the user. Additionally, the graphical button  212  may represent a function by which the user may access video files stored on the device  10 . Finally, the graphical button  214  may provide the user with a listing of options that the user may configure to further customize the functionality of the device  10  and the media player application  74 . 
     As discussed above, during operation of the device  10 , various events, including user events and system events may occur, as defined above. For instance, the visual notification window  218  may be displayed on the screen  200  to indicate that a user event  216  has occurred in response to actions initiated by a user to enable the media player application  74  to accept incoming network connections. As shown in  FIG. 12 , the window  218  may include the visual notification message  220 , as well as the decision button  222 , which may deny incoming network connections if selected, and the decision button  224 , which may allow incoming network connections if selected. 
     In the present context, the “contextual importance” of the event  216  may be relatively high due to the fact that a user input is required in order to carry out or not carry out the requested operation (e.g., the allowance of incoming network connections). That is, without a response from the user, the device  10  is unable to proceed, as the user has not confirmed or denied the allowance of incoming network connections. Thus, an audio feedback data set associated with the event  216  may include at least a non-verbal audio tone  226  that signifies the high contextual importance of the event  216  when played back, with a goal of prompting the user to respond to the visual notification window  218 . For example, the non-verbal tone  226  may include a distinctive alarm sound, a chirp, a beep, or any other type of non-verbal audio tone that may highlight the contextual importance of the event  216  (e.g., higher pitched sound, louder volume, longer playback time, etc.). In other words, while the event  216  may also be associated with one or more verbal audio items, in situations where either the audio user interface  38  selects the non-verbal audio item  226  or in which the user configures the device  10  to play back only non-verbal audio feedback, the non-verbal audio item  226  may help audibly distinguish the event  216  from events of lesser contextual importance. 
     To provide an example, an event that initially has lower contextual importance relative to the event  216  may be a system event in the form of a low battery warning  228 . For instance, upon the occurrence of the low battery warning event  228 , the visual notification window  230  is displayed on the screen  200 , and contains the visual notification message  232  indicating that the power source  30  ( FIG. 1 ) of the device  10  has 20% of its full charge capacity remaining The window  230  also includes the graphical button  234 , which the user may select to remove the window  230  from the screen  200 . Thus, unlike the event  216 , the device  10  does not require a decision input. 
     Ideally, the user will mentally process the notification provided by the window  230  and take necessary actions to recharge the power source  30 . However, the device  10  will continue to operate in the near term regardless of whether or not the user initiates recharging of the power source  30  immediately. In this context, the contextual importance of the event  228  may be regarded as generally low relative to the event  216 . As such, the event  228  may have associated therewith a non-verbal audio item  236  that is less distinct (e.g., lower pitched, softer volume, shorter playback time, etc.) relative to the non-verbal audio item  226 , thus signifying the lesser contextual importance of the event  228 . 
     While the event  228  may initially be categorized as having low contextual importance, it should be appreciated that the context in which the event  228  occurs may change over time. For instance the notification  230  may be a first warning based on a low power notification threshold of 20%. However, assuming the user chooses not to take action to replenish the power source  30 , the device  10  will continue to consume the remaining power, thus further depleting the power source  30 . Accordingly, in some embodiments, the user interface  34  may be configured to supply additional warnings at one or more lower thresholds. For instance, in one embodiment, the user interface  34  may supply a subsequent low power warning when the remaining charge in the power source  30  is depleted to 1% of total charge capacity. In this context, the 1% warning may be regarded as having high contextual importance, as the device  10  would be unable to continue operating when the power source  30  inevitably becomes fully depleted absent recharging or replacement. Thus, the latter example represents an embodiment in which multiple non-verbal items (e.g., of the same verbosity level) are associated with a common event, such that during the initial 20% warning event, a non-verbal audio item indicating low contextual importance may be played, and during the subsequent 1% warning event, another non-verbal audio item indicating high contextual importance may be played by the audio user interface  38 . 
     In additional embodiments, the contextual importance of the events  226  or  230  may be determined based upon pre-programmed information (e.g., events may be programmed as having high or low contextual importance characteristics), which may be established by the manufacturer of the device  10  or the programmer of the audio user interface  38 , or later configured/modified by a user, such as through the user preference settings  96  ( FIG. 4 ). In other embodiments, the contextual importance of the events  226  or  230  may be adaptive or learned based upon previous device behavior and/or how a user interacts with the device during previous occurrence(s) of the user interface event. For instance, in one embodiment, a current event (e.g.,  226  or  230 ) may be identified as having higher contextual importance if it is determined that the same type of event occurred frequently within a particular interval of time immediately preceding the current occurrence, or may be identified as having lower contextual importance if the same type of event rarely occurred or did not occur at all within the particular interval of time immediately preceding the current occurrence. 
       FIG. 13  provides a flowchart that depicts a method  240  for varying audio feedback based upon contextual importance, as described in  FIG. 12 . For instance, beginning at step  242 , the method  240  may detect an event requesting audio feedback. Next, at step  244 , the contextual importance of the event is determined. For instance, as discussed above, this step may, in some instances, include determining whether or not action on the user&#39;s part is necessary for the device to continue operating. Subsequently, at step  246 , an audio item is selected based upon the contextual importance of the event, as determined at step  244 . For example, if the event has low contextual importance, the less distinct non-verbal tone  236  may be played back, and if the event has high contextual importance, the more distinct non-verbal tone  226  may be played back. 
     Continuing to  FIGS. 14-18 , embodiments illustrating how audio feedback may be varied based upon the manner in which a user navigates a list of items displayed on a device  10  are illustrated in accordance with aspects of the present disclosure. For instance, referring first to  FIG. 14 , screen images depicting how a user may access a listing of songs in the media player application  74  are illustrated. Screens  72  and  200  are similar to those shown in  FIG. 12 , and depict the initiation of the media player application  74  and the navigation from the home screen  72  to the screen  200 , which displays the listing  202  of playlists  204 . 
     By selecting the graphical button  210  the user may be navigated to the screen  250 , which may display a navigable list  252  of music files (songs)  254  stored on the device  10  alphabetically. For instance, as shown in  FIG. 14 , the first song in the list  252  is referred to by reference number  256 . To select a particular song for playback, the user may select a displayed song using an input structure  14  of the device  10  (e.g., a touchscreen). The screen  250  may also include a scroll bar element  258  to provide a scrolling function. Thus, where the listing  252  of the music files  254  exceeds the display capabilities of the device  10 , the user may interface with the scroll bar element  258  to navigate the remainder of the list  252 . Upon selection of a particular item for playback, referred to here by reference number  260 , the user may continue to the screen  264 . 
     As shown in the screen  264 , information pertaining to the selected music file  260  is displayed. For instance, the displayed information may include the name of the recording artist, the title of the selected music file  260 , and, in some embodiments, the album with which the selected music file  260  is associated. The screen  264  may also display the album artwork  266  and the graphical buttons  268 ,  270 , and  272 . As will be appreciated, the graphical button  268  may allow the user to pause or un-pause the playback of the selected music file  260 . Additionally, where the presently selected media file  260  is part of a playlist, the graphical buttons  270  and  272  may represent the functions to returning to a previous file in the playlist or to continue to the subsequent file in the playlist. As can be appreciated, where a playlist is being played in a random mode or shuffle mode, the graphical buttons  270  and  272  may function select a random file from the playlist for playback. The screen  264  also includes a sliding bar element  274 , which may be manipulated by the user to control the volume of the audio playback. For the purposes of the list navigation examples discussed below with respect to  FIGS. 15-17 , it is assumed that the user pauses the playback of the selected music file  260  (by selecting the graphical button  268 ) and returns to the list  252  on the screen  250  by selecting the graphical button  262  on the screen  264 . 
     Referring now to  FIGS. 15-17 , examples of how audio feedback may be varied based upon the speed at which navigates a list, such as the song list  252 , are illustrated in accordance with aspects of the present disclosure. In the illustrated examples, each song file in the list  252 , beginning with the initial list item  256 , is given a list position reference label, beginning with L0 for the first item  256 , L1 for the second item, and so forth. It should be understood that the techniques disclosed herein may be applied to both vertical navigation of a list, as well as horizontal navigation of a list. 
     As depicted in  FIG. 15 , the list  252  is navigated a first speed  280 . The first navigation speed  280  may be relatively slow, and may allow enough time between the transition of one list item to another list item to provide full verbosity audio feedback for each of the list items. For instance, in the depicted example, the user may begin navigating the list  252  by scrolling down the list from first list item L0 and stopping at the list item L3. During this action, the title of each song and the name of the recording artist may be spoken by the audio user interface  38  for each of the songs L0, L1, L2, and L3, as shown in Table 1 below: 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 List Navigation at First Speed with Full Verbosity Audio Feedback 
               
            
           
           
               
               
               
            
               
                   
                 List Item 
                 Audio Feedback 
               
               
                   
                   
               
               
                   
                 L0 
                 Speak full song title followed by artist name 
               
               
                   
                 L1 
                 Speak full song title followed by artist name 
               
               
                   
                 L2 
                 Speak full song title followed by artist name 
               
               
                   
                 L3 
                 Speak full song title followed by artist name 
               
               
                   
                   
               
            
           
         
       
     
     In accordance with the presently disclosed techniques, the audio user interface  38  may be configured to adapt to slight changes in the navigation speed  280 . For instance, in one situation, the navigation speed may increase slightly, such that the transition time between list items reduced to allot enough time for speaking only one of the two audio items (e.g., song title or artist name). In one embodiment, the audio user interface  38  may still provide full verbosity audio feedback with respect to the song title information, but may omit the information regarding the artist name. 
     Next,  FIG. 16  shows an example in which the navigation speed  282 , which is notably increased relative to the navigation speed  280  of  FIG. 15 , does not provide enough transition time between list items to allow for full verbosity audio feedback. To provide an example, the navigation speed may be expressed based upon a number of list items navigated per second of time (e.g., List Items/second). By way of example only, the navigation speed  282  may be approximately 2 list items per second (or 1 list item per half second), whereas the navigation speed  280  shown in  FIG. 15  may be notably slower, such as 0.25 list items per second (or 1 list items every 4 seconds). 
     In the present example of  FIG. 16 , the user may navigate from the first list item L0 to the list item L11 using the navigation speed  282 . To accommodate for the reduced transition time between each list item when navigating at the speed  282 , the audio user interface  38  may, in one embodiment, devolve the audio feedback associated with the list navigation by speaking only the letter corresponding to the alphabetical order of a list item if that list item is the first item within an alphabetical grouping (e.g., song titles starting with “A,” “B,” etc.), and providing a non-verbal tone for each other list item. This embodiment is depicted below in Table 2. 
                     TABLE 2                  List Navigation at Second Speed with Reduced Verbosity Audio Feedback                             List Item   Audio Feedback                       L0   Speak the letter “A”           L1   Nonverbal tone           L2   Nonverbal tone           L3   Nonverbal tone           L4   Speak the letter “B”           L5   Nonverbal tone           L6   Nonverbal tone           L7   Nonverbal tone           L8   Nonverbal tone indicating new content           L9   Speak the letter “C”           L10   Nonverbal tone           L11   Speak the letter “D”                        
Additionally, as indicated by the list item L8, the audio user interface  38  may also be configured to selectively provide non-verbal tones based on the “newness” of the list item. For instance, the list item L8 may represent a song that was recently purchased from an online digital media service, such as the iTunes® service, provided by Apple Inc. Thus, in order to emphasize the newness of the song L8, the audio user interface  38  may play a non-verbal tone that is more distinct (e.g., a higher pitched beep) relative to the non-verbal tones played for older content (e.g., L6, L7, etc.) when the newer song L8 is reached during navigation. As will be appreciated, the “newness” threshold may be configured through user preferences  96  on the device  10 . By way of example, a user may configure the device  10  to identify content purchased or downloaded with the last 3 days as being new content.
 
     In another embodiment, the identification of “newer” content may include defining multiple tiers of newness. For instance, in addition to using a 3 day threshold for identifying the newest content on the device  10 , a second threshold (e.g., 14 days) may be established to detect content that is still relatively recent. In such embodiments, different non-verbal tones may be used for list items that are identified as being newest and recent items, with the non-verbal tone for recent items being less distinct than the non-verbal tone associated with the newest items, but with both the non-verbal tones for recent and newest items being substantially more distinct relative to a non-verbal tone used for items not identified as being new or recent (e.g., items older than 14 days). Indeed, those skilled in the art will appreciate that any number of non-verbal tones for distinguishing between the age of content stored on the device  10  (e.g., based on any number of tiers defined by corresponding thresholds) may be utilized in various embodiments of the present technique. 
     Continuing to  FIG. 17 , an additional example depicting the navigation of the list  252  at the speed  284 , which is even greater relative to the speed  282  of  FIG. 16 , is provided. By way of example only, the navigation speed  284  may be approximately 4 list items per second. In the present example, the user may navigate from the first list item L0 to the list item L18 using the navigation speed  284 . To accommodate for an even further reduced transition time between each list item when navigating at the speed  284 , the audio user interface  38  may further devolve the audio feedback such that audio feedback is provided only for a portion of the list items. For instance, as shown in Table 3 below, the audio user interface  38  may, in one embodiment, devolve the audio feedback associated with the list navigation by speaking the letter corresponding to the alphabetical order of a list item for the first list items within each alphabetical grouping (e.g., song titles starting with “A,” “B,” etc.), and playing a non-verbal tone for only every third list item (e.g., items L2, L5, L8, and L17). For list items that qualify for the playback of a non-verbal tone and are also the first item in an alphabetical group, the alphabetical letter may be spoken in lieu of the non-verbal tone (e.g., items L11 and L14). 
     
       
         
           
               
             
               
                 TABLE 3 
               
             
            
               
                   
               
               
                 List Navigation at Third Speed with Reduced Verbosity Audio Feedback 
               
            
           
           
               
               
               
            
               
                   
                 List Item 
                 Audio Feedback 
               
               
                   
                   
               
               
                   
                 L0 
                 Speak the letter “A” 
               
               
                   
                 L1 
               
               
                   
                 L2 
                 Nonverbal tone 
               
               
                   
                 L3 
               
               
                   
                 L4 
                 Speak the letter “B” 
               
               
                   
                 L5 
                 Nonverbal tone 
               
               
                   
                 L6 
               
               
                   
                 L7 
               
               
                   
                 L8 
                 Nonverbal tone indicating new content 
               
               
                   
                 L9 
                 Speak the letter “C” 
               
               
                   
                 L10 
               
               
                   
                 L11 
                 Speak the letter “D” 
               
               
                   
                 L12 
               
               
                   
                 L13 
               
               
                   
                 L14 
                 Speak the letter “E” 
               
               
                   
                 L15 
               
               
                   
                 L16 
               
               
                   
                 L17 
                 Nonverbal tone 
               
               
                   
                 L18 
                 Speak the letter “G” 
               
               
                   
                   
               
            
           
         
       
     
     As will be appreciated, in other embodiments, the frequency at which the non-verbal tones are provided may further decrease (e.g., every fourth, fifth, or sixth item) as the list navigation speed continues to increase. Further, it should be understood that the navigation of the list  252  may not necessarily occur a constant speed. Thus, the audio user interface  38  may adjust the verbosity of the audio feedback accordingly. For instance, if the user initially navigates the list  252  very slowly (e.g., speed  280 ), and gradually increases to a faster speed (e.g., speed  284 ), the audio user interface  38  may initially provide full verbosity audio feedback for multiple segments of data (e.g., song title and artist name), and gradually devolve the verbosity to providing only the song title and eventually reaching a devolved verbosity scheme similar to that shown in Table 3. If the user subsequently gradually decreases the navigation speed, then the audio feedback may also gradually evolve back towards the full verbosity mode. 
     Moreover, while the present techniques have been illustrated in conjunction with a graphical user interface, it should be understood that certain embodiments may include only an audio user interface. In such embodiments, the above-described audio feedback techniques may be applied as the user may navigate through a listing of items (e.g., using a scroll wheel) without a corresponding visual interface. As mentioned above, an embodiment of the device  10  that lacks a display  22  and thus a graphical user interface may be a model of an iPod® Shuffle, available from Apple Inc. 
     The various techniques for varying audio feedback during list navigation, as described with reference to the embodiments shown in  FIGS. 15-17  and in Tables 1-3, are generally summarized by the method  290 , depicted by the flowchart shown in  FIG. 18 . The method  290  begins at step  292 , at which a list navigation event is detected. For instance, a list navigation event may include the transition from one list item (e.g., L0) to a subsequent list item (e.g., L1). At step  294 , the current list item is identified. Thereafter, at decision block  296 , a determination is made as to whether the user&#39;s navigation speed permits full verbosity audio feedback. By way of example, the navigation speed may be determined in one embodiment by calculating an average of the speeds at which the transition between two or more immediately preceding list items occurred (e.g., or succeeding items if the user is navigating up a list). If it is determined that the navigation speed allows for full verbosity audio feedback, the method  290  continues to step  298 , whereby one or more full verbosity audio items associated with the currently selected list item are played back. 
     If the navigation speed at decision block  296  does not permit full verbosity audio feedback, the method  290  continues to decision block  300 , at which a determination is made as to whether the current list item is the first item of an alphabetical group and, if so, the letter of the alphabetical group is spoken by the audio user interface  38  and provided as audio feedback (step  302 ). If the current list item is not the first item of an alphabetical group, the method  290  proceeds to decision block  304 , whereby the newness of the current list item is determined. If the current list item is identified as being new content, then a distinct non-verbal audio item that indicates the newness of the current list item is played, as indicated at step  306 . If the current list item is not identified as being new content, then a less distinct non-verbal audio item is played instead, as indicated at step  308 . 
       FIGS. 19-21  depict various screens images showing how audio feedback options may be configured on the device  10 , in accordance with one embodiment. For instance, referring first to the screen  310  of  FIG. 19 , a main “home” screen  312  of a GUI  36  for an operating system is illustrated. By way of example, the operating system may be a version of the Mac OS® operating system from Apple Inc. As discussed in  FIG. 2 , the GUI  36  may provide a dock  58  that includes various icons  56 . The selection of the icon  316  may cause the graphical window  318  to be displayed. As shown, the graphical window  318  includes additional icons  56  that may relate the configuration of various aspects of system preferences for the device  10 . Particularly, the graphical icon  320  may represent a function for configuring an audio user interface  38 . 
     Referring to  FIG. 20 , the selection of the icon  320  may cause the graphical configuration window  322  to be displayed. Initially, the configuration window  322  includes the graphical switches  324 ,  326 ,  328 , and  330 . The switch  324 , currently in the “ON” position, may enable or disable the audio user interface  38 , while the switches  326 ,  328 , and  330  may be toggled to allow the audio user interface  38  to operate in different modes. For instance, the switch  326 , currently in the “ON” position, indicates that a constant full verbosity mode is presently enabled, and that the additional modes for devolving/evolving audio feedback (switch  328 ) and for using only non-verbal audio feedback (switch  330 ) are both presently disabled. 
       FIG. 21  depicts the configuration window  322  following the performance of various configuration steps by a user. For instance, as shown, the switch  326  is toggled to the “OFF” position to disable the constant full verbosity mode, and the switch  328  is toggled to the “ON” position to indicate that the adaptive devolving/evolving mode has been enabled. Upon enabling the devolving/evolving mode, a set of additional configuration parameters  332  may be displayed and configured by the user. For instance, the user may enable or disable each of the configuration parameters  332  by toggling the graphical switches  334 ,  338 ,  340 ,  342 ,  344 ,  346 , and  350  to desired positions. The user may also utilize the selection field  336  to specify a step-up time, as discussed above with reference to  FIGS. 8 and 9 . Additionally, the user may utilize the selection field  348  to specify a threshold for distinguishing between newer and older content during list navigation, as discussed above with reference to  FIGS. 15-17 . 
     In summary, the embodiments presented above provide an intelligent and adaptive technique by which an electronic device (e.g., device  10 ) is capable of evolving and devolving of audio feedback verbosity in response to user inputs and/or in response to external stimuli. For instance, based on user actions and or user-defined preferences (e.g., preferences  96 ) the specific actions for devolving and/or evolving audio feedback may be dynamic and adaptive. By way of example, as shown in  FIG. 9  above, the detection of a user action in the form of a playback termination event may cause the device  10  to increase the rate of devolution (e.g., devolves verbosity faster due to the indication that the user is not interested in the audio feedback corresponding to the terminated event). Additionally, the external stimuli not caused by user inputs, such as low power events or the detection of network connections ( FIG. 12 ) may also cause the device  10  to increase or decrease the verbosity of audio feedback (e.g., based on contextual importance). Indeed, the presently described techniques offer a robust and adaptive system for adjusting the verbosity of audio feedback provided by an audio user interface. 
     Further, as will be understood, the various techniques described above and relating to adaptively varying audio feedback provided by an audio user interface of an electronic device are provided herein by way of example only. Accordingly, it should be understood that the present disclosure should not be construed as being limited to only the examples provided above. Indeed, a number of variations of the audio feedback techniques set forth above may exist. Further, it should be appreciated that the above-discussed techniques may be implemented in any suitable manner. For instance, audio user interface  38  and the audio feedback selection logic  86 , which are collectively configured to implement various aspects of the presently disclosed techniques, may be implemented using hardware (e.g., suitably configured circuitry), software (e.g., via a computer program including executable code stored on one or more tangible computer readable medium), or via using a combination of both hardware and software elements. 
     The specific embodiments described above have been shown by way of example, and it should be understood that these embodiments may be susceptible to various modifications and alternative forms. It should be further understood that the claims are not intended to be limited to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure.

Metadata:
Filing Date: 20100113
Publication Date: 20130219
Grant Date: 20130219
Priority Date: 20100113
Inventors: ROTTLER BENJAMIN ANDREW
LINDAHL ARAM
HAUGHAY, JR. ALLEN PAUL
ELLIS SHAWN A.
WOOD POLICARPO
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/167", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0482", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0482", "inventive": true, "first": false, "tree": "[]"}, {"code": "G10L15/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "G10L13/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/167", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/048", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/16", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 43768975