ITCS 6010 SALT

Speech Application Language Tags (SALT) Speech interface markup language Extension of HTML and other markup languages Adds speech and telephony features to Web applications and services for both voice only and multimodal browsers

SALT Overview SALT Small set of XML elements Elements have: Attributes DOM (Document Object Model) object properties Events Methods Applies speech to source page when used in conjunction with source markup document

SALT Design Principles Clean integration of speech with Web pages Leverages event-based DOM execution model of Web pages Integrates cleanly into visual markup pages Reuses knowledge and skill of Web developers Does not reinvent page execution or programming models

SALT Design Principles (cont’d) Separation of speech interface from business logic and data Individual markup language not directly extended Provides separate layer extensible across different markup languages Allows for loose or tight coupling of speech interface to underlying data structure Enables reuse of speech and dialog components across pages and applications

SALT Design Principles (cont’d) Power and flexibility of programming model SALT elements are simple and intuitive Offer fine-level control of dialog execution through DOM event and scripting model Leverages benefits of rich and well- understood execution environment

SALT Design Principles (cont’d) Reuses existing standards for grammar, speech output and semantic results Range of devices Designed for range of architectural scenarios Not for particular device type

SALT Design Principles (cont’d) Minimal cost of authoring across modes and devices Enables 2 important classes of application scenario 1) Multimodal o Visual page enhanced with speech interface on same device 2) Cross-modal o Single application page reused for different modes on different devices

Top-level Elements There are 4 main top-level elements: For speech synthesis and prompt playing For speech recognition For configuration and control of DTMF collection For general purpose communication with platform components

Top-level Elements listen and DTMF elements May contain and elements listen element May contain element

Element Used for speech input Specifies grammars Specifies means of dealing with speech recognition results Used for recording spoken input Handles speech events and configures recognizer properties Activates/deactivates grammars Starts/stops recognition

Element (cont’d) example <salt:bind targetElement=“txtBoxOriginCity” value=“/result/origin_city” />

Element (cont’d) element Can be executed with Start() method in script Can be executed declaratively in scriptless environment Handlers include events for: Successful recognitions Misrecognitions Timeouts Each recognition event can be configured via attributes for: Timeout periods Confidence thresholds

Element Used to specify grammars Inline or referenced Multiple grammar elements may be used in single Individual grammars may be activated/deactivated before recognition begins Independent of grammar format Will support at minimum XML form of W3C Speech Recognition Grammar Specification

Element Used to inspect result of recognition Conditionally copies relevant portions to values in page Multiple bind elements may be used in single Recognition result returned in XML document form Uses XPath syntax in value attribute Uses and XML pattern query in test attribute

Element (cont’d) Value attribute To reference particular node of result Test attribute To specify binding conditions If condition evaluates to true, node content bound to page element specified by targetElement attribute

Element Example  Recognition example London code

Element Used to specify audio recording parameters Results may be processed with bind or scripted code

Element Used to specify system output Content may include: Text Speech output markup Variable values Links to audio files Mix of any of the above

Element (cont’d) Executed in 2 ways ways: 1) Declaratively on scriptless browser 2) By object methods in script  Contains methods to start, stop, pause and resume prompt playback, and alter speed and volume  Handlers include events for user barge-in, prompt- completion and internal ‘bookmarks’

Element Example So you want to travel from to ?

Element Used to specify DTMF grammars in telephony applications Deals with keypress input and other events Executed declaratively or programmatically with start and stop commands

Element (cont’d) Main elements include and Holds resources for configuring DTMF collection process Configured via attributes for configuring timeouts Handlers include keypress events, valid dtmf sequences and out-of-grammar input

Element Example

Event writing SALT elements contain methods, properties and event handlers accessible to script Enable interaction with other events and processes in Web page Because SALT elements are XML objects in DOM of page

Event writing (cont’d) Top-level elements contain asynchronous methods for initiation and completion of execution Contain properties For configuration and result storing Event handlers For events associated with speech

Event writing onReco Event fired when recognition results successfully returned onBargein Event fired on prompt element if user input received during prompt playback

Code Examples <salt:bind targetElement="txtBoxDestCity" value="/result/city" />

Code Examples (cont’d) <salt:bind targetElement="txtBoxOriginCity" value="/result/originCity" /> <salt:bind targetElement="txtBoxDestCity" value="/result/destCity" />

Where would you like to leave from? Where would you like to go to? Sorry, I didn't understand. function RunAsk() { if (travelForm.txtBoxOriginCity.value=="") { askOriginCity.Start(); recoOriginCity.Start(); } else if (travelForm.txtBoxDestCity.value=="") { askDestCity.Start(); recoDestCity.Start(); } function procOriginCity() { travelForm.txtBoxOriginCity.value = recoOriginCity.text; RunAsk(); } function procDestCity() { travelForm.txtBoxDestCity.value = recoDestCity.text; travelForm.submit(); }