Voice Extensible Markup Voice Extensible Markup

LanguageLanguage VXMLVXML

Dreadi DavisDreadi DavisTim CortinaTim Cortina

OverviewOverview

OverviewOverview History/ApplicationHistory/Application Elements/Basics (w/ examples)Elements/Basics (w/ examples) GrammarsGrammars Example(s)Example(s)

OverviewOverview

““VoiceXML is designed for creating audio VoiceXML is designed for creating audio dialogs that feature synthesized speech, dialogs that feature synthesized speech, digitized audio, recognition of spoken and digitized audio, recognition of spoken and DTMF key input, recording of spoken input, DTMF key input, recording of spoken input, telephony, and mixed initiative conversations. telephony, and mixed initiative conversations. Its major goal is to bring the advantages of Its major goal is to bring the advantages of Web-based development and content delivery Web-based development and content delivery to interactive voice response applications.to interactive voice response applications.””

www.w3c.orgwww.w3c.org

OverviewOverview

VoiceXML creates voice applications to VoiceXML creates voice applications to run on the phone much in the way HTML run on the phone much in the way HTML is used to create visual applications for is used to create visual applications for the web.the web.

Supports both voice input and keypad Supports both voice input and keypad inputinput

Can be used to record spoken inputCan be used to record spoken input Grammars can be very strict, emulate Grammars can be very strict, emulate

natural language, or be anything in natural language, or be anything in betweenbetween

History/ApplicationHistory/Application

VXML specifications have been VXML specifications have been developed with the cooperation of a developed with the cooperation of a number of companiesnumber of companies AT&T (Bell Laboratories)AT&T (Bell Laboratories) MotorolaMotorola IBMIBM Lucent Technologies Lucent Technologies

History/ApplicationHistory/Application

Allow for telephone access to web Allow for telephone access to web applications without needing to applications without needing to purchase additional hardwarepurchase additional hardware

Wanted to replace touch-tone input Wanted to replace touch-tone input with a hands-free approachwith a hands-free approach

ApplicationApplication

Used in conjunction with voice Used in conjunction with voice recognizing software, java servlets, recognizing software, java servlets, ……

VoiceGenieVoiceGenie SpeechworksSpeechworks

Basics/ElementsBasics/Elements

Start every page with:Start every page with: <?xml version="1.0" encoding="UTF-8"?><?xml version="1.0" encoding="UTF-8"?>

Top Level Element:Top Level Element: <vxml version=“2.0”><vxml version=“2.0”>

Namespaces:Namespaces: xmlns=xmlns=http://www.w3.org/2001/vxmlhttp://www.w3.org/2001/vxml xmlns:xsi=xmlns:xsi=

http://www.w3.org/2001/XMLSchema-instancehttp://www.w3.org/2001/XMLSchema-instance xsi:schemaLocation="http://www.w3.org/2001/xsi:schemaLocation="http://www.w3.org/2001/

vxmlvxml http://www.w3.org/TR/voicexml20/vxml.xsd http://www.w3.org/TR/voicexml20/vxml.xsd

Hello World ExampleHello World Example

<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?> <vxml xmlns="http://www.w3.org/2001/vxml" <vxml xmlns="http://www.w3.org/2001/vxml"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" instance" xsi:schemaLocation="http://www.w3.org/2001/vxml xsi:schemaLocation="http://www.w3.org/2001/vxml http://www.w3.org/TR/voicexml20/vxml.xsd" http://www.w3.org/TR/voicexml20/vxml.xsd" version="2.0">version="2.0"><form><form>

<block>Hello World!</block><block>Hello World!</block></form></form>

</vxml></vxml> www.w3c.orgwww.w3c.org

Example With InputExample With Input

(see Example1.vxml)(see Example1.vxml)

GrammarsGrammars

Define what input will be acceptable Define what input will be acceptable from the user.from the user.

They can define:They can define: Length of input (in time)Length of input (in time) Type of input (voice/DTMF)Type of input (voice/DTMF)

(DTMF=Dual Tone Multi-Frequency)(DTMF=Dual Tone Multi-Frequency) The specific options/responses allowedThe specific options/responses allowed

(see examples)(see examples)

Built-in GrammarsBuilt-in Grammars

VXML comes with predefined grammars VXML comes with predefined grammars that would be common, yet large to writethat would be common, yet large to write DigitsDigits Boolean (yes, no, …)Boolean (yes, no, …) DateDate Currency (multiple, not just US)Currency (multiple, not just US) Number (includes decimal points, and +/-)Number (includes decimal points, and +/-) PhonePhone TimeTime

Used: <grammar src=“builtin:digits”/>Used: <grammar src=“builtin:digits”/>

Natural Language Natural Language GrammarsGrammars

Designed to emulate how people Designed to emulate how people would normally speak/respondwould normally speak/respond

If asked “what do you want to do?”, If asked “what do you want to do?”, in a banking application, you might in a banking application, you might say,say, Hear my balanceHear my balance I’d like to find out what my balance isI’d like to find out what my balance is I need to know how much money I have I need to know how much money I have

in my accountsin my accounts

Natural Language Natural Language GrammarsGrammars

Usually too complicated to handle by Usually too complicated to handle by handhand

(Not likely to think of all of the possible (Not likely to think of all of the possible combinations of words)combinations of words)

SpeakFreely tool (Speechworks)SpeakFreely tool (Speechworks) Create vocabularyCreate vocabulary Create training sentencesCreate training sentences Create testing sentencesCreate testing sentences Compile with the toolCompile with the tool

(see example)(see example)

Error CatchingError Catching

<catch event="error.internal"><catch event="error.internal">An Internal error has been caught.An Internal error has been caught.<log> <value expr="_message"/> </log><log> <value expr="_message"/> </log><exit/><exit/>

</catch></catch><catch event="error.asr"><catch event="error.asr">

A Speech Recognition error has been A Speech Recognition error has been caught.caught.<log> <value expr="_message"/> </log><log> <value expr="_message"/> </log><exit/><exit/>

</catch></catch>

ReferencesReferences

http://developer.voicegenie.comhttp://developer.voicegenie.com www.w3c.org/TR/voicexml20/www.w3c.org/TR/voicexml20/ http://www.voicexml.org/http://www.voicexml.org/