Files
asterisk/contrib
George Joseph 2d22e34206 ACN: res_pjsip endpoint options
This commit adds the endpoint options required to control
Advanced Codec Negotiation.

incoming_offer_codec_prefs
outgoing_offer_codec_prefs
incoming_answer_codec_prefs
outgoing_answer_codec_prefs

The documentation may need tweaking and some additional edits
added, especially for the "answer" prefs.  That'll be handled
when things finalize.

This commit is safe to merge as it doens't alter any existing
functionality nor does it alter the previous codec negotiation
work which may now be obsolete.

Change-Id: I920ba925d7dd36430dfd2ebd9d82d23f123d0e11
2020-07-08 09:03:58 -05:00
..
2018-10-15 15:35:35 -05:00

app_festival is an application that allows one to send text-to-speech commands
to a background festival server, and to obtain the resulting waveform which
gets sent down to the respective channel. app_festival also employs a waveform
cache, so invariant text-to-speech strings ("Please press 1 for instructions")
do not need to be dynamically generated all the time.

You need :

1) festival, patched to produce 8khz waveforms on output. Patch for Festival
1.4.2 RELEASE are included. The patch adds a new command to festival
(asterisk_tts).

It is possible to run Festival without patches in the source-code. Just
add this to your /etc/festival.scm or /usr/share/festival/festival/scm:

    (define (tts_textasterisk string mode)
    "(tts_textasterisk STRING MODE)
    Apply tts to STRING. This function is specifically designed for
    use in server mode so a single function call may synthesize the string.
    This function name may be added to the server safe functions."
    (let ((wholeutt (utt.synth (eval (list 'Utterance 'Text string)))))
    (utt.wave.resample wholeutt 8000)
    (utt.wave.rescale wholeutt 5)
    (utt.send.wave.client wholeutt)))

[See the comment with subject "Using Debian
 festival >= 1.4.3-15 (no recompiling needed!)" on
 http://www.voip-info.org/wiki-Asterisk+festival+installation for the
 original mentioning of it]

2) You may wish to obtain and install the asterisk-perl
module by James Golovich <james@gnuinter.net>, from
either CPAN, or his site: http://asterisk.gnuinter.net,
as this contains a good example of how variable text
can be tts'd via asterisk, namely the examples/tts-*.agi
files there. It has been noted that the current expression
evaluation capabilities of asterisk are not best suited
for the generation and manipulation of text. AGI scripting
can be ideal for these sorts of needs. For simpler usage,
fixed, pre-recorded messages may be more amenable for your
purposes.

3) Before running asterisk, you have to run festival-server with a command
like :

/usr/local/festival/bin/festival --server > /dev/null 2>&1 &