Connects to the locally running Festival server, sends it the text specified by text, and plays the resulting sound file back to the user. This application allows the caller to press a key (specified by intkeys) to immediately stop the playback and return the value of intkeys. If intkeys is set to any, Festival() will send control of the channel to the extension entered by the user.

See Chapter 14, Potpourri for more in-depth information on using Festival with Asterisk and the README.festival file located in the contrib/ subdirectory of the Asterisk source.

You must start the Festival server before starting Asterisk, and you must use the Answer() application to answer the channel before calling Festival().

exten => 123,1,Answer()
exten => 123,2,Festival('This is sample speech from Festival',#)