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Whats UCMA 3.0 Voicexml Browser default audio format? RRS feed

  • Question

  • Currently, I am developing a ucma 3.0 vxml application. The following is some code in the VoiceXml document.

    <form> <record  name="msg" beep="true" maxtime="10s"  dtmfterm="true" type="audio/x-wav">
          
    <prompt timeout="5s">
             Record a message after the beep.
          
    </prompt>
          
    <noinput>
             I didn't hear anything, please try again.
          
    </noinput>
        
    </record>

     
    <block>
       
    <submit next="http://SomeServer//SomePage.aspx"  enctype="multipart/form-data" method="post" namelist="msg"/>
     
    </block>    

    </form>

    At SomeServer/SomePage.aspx , save the posted recording to a wav file.whats the format of the saved wav file, 8KHz/8-bit or 8KHz/16-bit or 16KHz/16-bit?

    Voicexml specification 2.0 requires that all platforms must support the playing and recording audio formats specified below:

    • Raw (headerless) 8kHz 8-bit mono mu-law [PCM] single channel. (G.711) -- audio/basic (from [RFC1521])
    • Raw (headerless) 8kHz 8 bit mono A-law [PCM] single channel. (G.711) -- audio/x-alaw-basic
    • WAV (RIFF header) 8kHz 8-bit mono mu-law [PCM] single channel. -- audio/x-wav
    • WAV (RIFF header) 8kHz 8-bit mono A-law [PCM] single channel. -- audio/x-wav

    I need to get 16KHz 16-bit mono pcm recording? Is this possible?(UCMA 3.0 VoiceXml application)

    Sunday, September 23, 2012 8:22 AM

Answers

  • Currently, I am developing a ucma 3.0 vxml application. The following is some code in the VoiceXml document.

    <form> <record  name="msg" beep="true" maxtime="10s"  dtmfterm="true" type="audio/x-wav">
          
    <prompt timeout="5s">
             Record a message after the beep.
          
    </prompt>
          
    <noinput>
             I didn't hear anything, please try again.
          
    </noinput>
        
    </record>

     
    <block>
       
    <submit next="http://SomeServer//SomePage.aspx"  enctype="multipart/form-data" method="post" namelist="msg"/>
     
    </block>    

    </form>

    At SomeServer/SomePage.aspx , save the posted recording to a wav file.whats the format of the saved wav file, 8KHz/8-bit or 8KHz/16-bit or 16KHz/16-bit?

    Voicexml specification 2.0 requires that all platforms must support the playing and recording audio formats specified below:

    • Raw (headerless) 8kHz 8-bit mono mu-law [PCM] single channel. (G.711) -- audio/basic (from [RFC1521])
    • Raw (headerless) 8kHz 8 bit mono A-law [PCM] single channel. (G.711) -- audio/x-alaw-basic
    • WAV (RIFF header) 8kHz 8-bit mono mu-law [PCM] single channel. -- audio/x-wav
    • WAV (RIFF header) 8kHz 8-bit mono A-law [PCM] single channel. -- audio/x-wav

    I need to get 16KHz 16-bit mono pcm recording? Is this possible?(UCMA 3.0 VoiceXml application)


    I haven't tried this myself, but I believe that you should be able to get a 16KHz, 16-bit PCM mono recording. The default constructor for the Browser class (Microsoft.Rtc.Collaboration.AudioVideo.VoiceXml namespace) seems to be able to handle sampling rates of either 8KHz or 16KHz, in 16-bit mono PCM.
    Thursday, December 13, 2012 9:06 PM