By default, input is supplied via standard input, but can also be specified from a file with the `-i` option.
Both plain text and SSML input are supported. Specify `-ssml` to tell the program to expect SSML input from your text source.
Run ```gsquawk -h``` to see the help.
Output is to a file, but you can set the filename to `-` to send to stdout. This can be useful if you want to convert the file on the fly to a format that gsquawk doesn't support, with **sox** or **ffmpeg** or the like.
Instead of performing TTS, you can use the `-listvoices` option to have gsquawk send you back a list of all available voices. If you run with `-listvoices` and no other options it limits to `en-US` voices, which is the default language selection. You may use the `-l` option along with `-listvoices` to set a specific language code, or use `-l ALL` to give you a list of every voice available in all languages.
Run ```gsquawk -h``` to see the help:
```
Usage of ./gsquawk:
--db float
Volume gain in dB. [-96 to 16]
Volume gain in dB. [-96 to 16]
-f string
Audio format selection. MP3 is 32k [mp3,opus,pcm,ulaw,alaw] (default "mp3")
Audio format selection. MP3 is 32k [mp3,opus,pcm,ulaw,alaw] (default "mp3")
-g string
Gender selection. [m,f,n] 'n' means neutral/don't care. (default "m")
Gender selection. [m,f,n] 'n' means neutral/don't care. (default "m")
-i string
Input file path. Defaults to stdin. (default "-")
Input file path. Defaults to stdin. (default "-")
-l string
Language selection. 'en-US', 'en-GB', 'en-AU', 'en-IN',
'el-GR', 'ru-RU', etc. (default "en-US")
Language selection. 'en-US', 'en-GB', 'en-AU', 'en-IN',
'el-GR', 'ru-RU', etc. (default "en-US")
-listvoices
List available voices, rather than generate TTS. Use in
combination with '-l ALL' to show voices from all languages.
-o string
Output file path. Use '-' for stdout. (default "./tts.mp3")
Output file path. Use '-' for stdout. (default "./tts.mp3")
-p float
Pitch. E.g. '0.0' is normal. '20.0' is highest,
'-20.0' is lowest. (default 1)
Pitch. E.g. '0.0' is normal. '20.0' is highest,
'-20.0' is lowest. (default 1)
-r int
Samplerate in Hz. [8000,11025,16000,22050,24000,32000,44100,48000] (default 24000)
Samplerate in Hz. [8000,11025,16000,22050,24000,32000,44100,48000] (default 24000)
-s float
Speed. E.g. '1.0' is normal. '2.0' is double
speed, '0.25' is quarter speed, etc. (default 1)
Speed. E.g. '1.0' is normal. '2.0' is double
speed, '0.25' is quarter speed, etc. (default 1)
-ssml
Input is SSML format, rather than plain text.
Input is SSML format, rather than plain text.
-v string
Voice. If specified, this overrides language & gender. (default "unspecified")
```
Voice. If specified, this overrides language & gender. (default "unspecified")
