Lua COM interface for Microsoft Speech API

Easy text-to-speech in Lua with MS SAPI ( https://en.wikipedia.org/wiki/Microsoft_Speech_API ).

Dependencies

LuaCOM ( https://github.com/davidm/luacom or maybe better https://github.com/moteus/luacom )

Note for use on non-Microsoft systems with Wine

SAPI speech functionality depends on the Microsoft Speech API, which is not included by default in Wine, and SpeechSDK51.exe must be separately installed. You can install it with winetricks speechsdk or download it from https://download.microsoft.com/download/B/4/3/B4314928-7B71-4336-9DE7-6FA4CF00B7B3/SpeechSDK51.exe

API

Function	Arguments	Returns	Description
say	string message		Speak the given string.
pause			Pause speaking.
resume			Resume speaking.
skip_sentence			Stop speaking the current line and move to the next line in the SAPI buffer.
skip_all			Stop speaking and clear the SAPI buffer.
set_voice_by_number	int SAPI_index, [bool quietly]	int SAPI_index, string SAPI_ID	Choose the SAPI voice indexed from 1 to n
set_voice_by_id	string SAPI_ID, [bool quietly]	int SAPI_index, string SAPI_ID	Choose the SAPI voice by its ID.
set_rate	int rate, [bool quietly]	int rate	Set the speech rate.
slower	[bool quietly]	int rate	Increment the speech rate.
faster	[bool quietly]	int rate	Decrement the speech rate.
set_filtering_level	int level, [bool quietly]	int level	Set the symbol filtering level, 1 being least and 3 being most filtering.
set_volume	int volume, [bool quietly]	int volume	Set the speech volume.
quieter	[bool quietly]	int volume	Decrement the speech volume.
louder	[bool quietly]	int volume	Increment the speech volume.
get_voice_id		string SAPI_ID	Return the SAPI voice ID string.
get_rate		int rate	Return the speech rate number.
get_filtering_level		int level	Return the filtering level number.
get_volume		int volume	Return the speech volume number.
say_current_voice			Speaks the current voice index and ID.
say_current_rate			Speaks the current speech rate.
say_current_filtering_level			Speaks the current symbol filtering level and description.
say_current_volume			Speaks the current speech volume.
list_voices			Speaks all of the available voices, index and ID.
list_filtering_levels			Speaks all of the filtering levels, index and description.
mute	[bool quietly]		Disables speech.
unmute	[bool quietly]		Re-enables speech.
speech_demo			Speaks a set of demonstration sentences.
print_spoken			Print spoken lines to the screen to aid debugging.

Variables	Description
replacements	Table of tables in the form {string pattern, string replacement} for filtering level 3 via string.gsub.

Usage Example

sapi_interface = require "sapi_interface"

if sapi_interface == -1 then
  print([[
  Could not open SAPI.
  Note for non-Microsoft operating systems...
  SAPI speech functionality depends on the Microsoft Speech API.
  This is not included by default in Wine, and SpeechSDK51.exe must be separately installed.
  You can download it from
  https://download.microsoft.com/download/B/4/3/B4314928-7B71-4336-9DE7-6FA4CF00B7B3/SpeechSDK51.exe
  ]])
  return
end

if sapi_interface == -2 then
  print("No SAPI voices found.")
  return
end

-- add a new filter
table.insert(sapi_interface.replacements, {"%f[%a][gG]clan", " G clan"})

sapi_interface.say("SAPI interface is ready")
sapi_interface.speech_demo()