8 Voice Lock ¶

See http://tvraman.github.io/emacspeak/blog/voice-lock-refreshed.html for a high-level overview of how Emacspeak Voice-Lock has evolved over the years.

Emacspeak defines a number of voice overlays such as ‘voice-bolden’, and ‘voice-lighten’ that can be applied to a given voice to change what it sounds like.
Voice overlays are defined in terms of Aural CSS (ACSS) to keep them independent of a specific TTS engine.
For each such overlay there is a corresponding ‘<overlay-name>-settings’ variable that can be customized via custom.
The numbers in ‘voice-bolden-settings as an example’:

Setting	Value
family	nil
average-pitch	1
pitch-range	6
stress	6
richness	nil
punctuation	nil

Unset values (‘nil’) show up as “unspecified” in the customize interface.

Do not directly customize ‘voice-bolden’ and friends, instead customize the corresponding ‘voice-bolden-settings’, since that ensures that all voices that are defined in terms of ‘voice-bolden’ get correctly updated.
Discovering what to customize:

Command ‘emacspeak-show-personality-at-point’ (bound by default to C-e M-v) will show you the value of properties personality and face at point. Describe-variable on these names should tell you what to customize; so as an example:

Put point on a comment line, and hit ‘C-e M-v’: you will hear

Personality emacspeak-voice-lock-comment-personality
Face font-lock-comment-delimiter-face

Describe-variable of ‘emacspeak-voice-lock-comment-personality’ gives:

emacspeak-voice-lock-comment-personality's value is acss-p0-s0-all

Documentation:
Personality used for font-lock-comment-face
This personality uses  voice-monotone whose  effect can be changed globally by customizing voice-monotone-settings.

[ << ]

[ < ]

[ Up ]

[ > ]

[ >> ]

[Top]

[Contents]

[Index]

[ ? ]

8.1 How It All Works ¶

Here is a brief explanation of the connection between ‘voice-bolden’ and its associated ‘voice-bolden-settings’.

Voice settings are initially in ‘voice-bolden-settings’ which is a list of numbers.
That list of numbers needs to be translated to appropriate device-specific codes to send to the TTS engine.
You do not want to do this translation each time you speak something.
So when ‘voice-bolden’ is defined, the definition happens in two steps:

The list of settings is stored away in ‘voice-bolden-settings’,
A corresponding voice-name is generated — ‘acss-a<n>-p<n>-r<n>-s<n>’ and the corresponding control codes to send to the device are stored away in a hash-table keyed by the above symbol.
Finally, ‘voice-bolden’ is assigned the above symbol.