This property controls the speaking rate. The default rate for a voice depends on the language and dialect and on the personality of the voice. The default rate for a voice should be such that it is experienced as a normal speaking rate for the voice when reading aloud text. Since voices are processor-specific, the default rate will be as well.
Name:
voice-rate
Value:
[normal | x-slow | slow | medium | fast | x-fast] || <percentage>
Initial:
normal
Applies to:
all elements
Inherited:
yes
Percentages:
refer to default value
Media:
speech
Computed value:
a keyword value, and optionally also a percentage relative to the keyword (if not 100%)
Syntax
voice-rate: [normal | x-slow | slow | medium | fast | x-fast] || <percentage> ;
Values
normal
Represents the default rate produced by the speech synthesizer for the currently active voice. This is processor-specific and depends on the language, dialect and on the “personality” of the voice.
x-slow, slow, medium, fast and x-fast
A sequence of monotonically non-decreasing speaking rates that are implementation and voice -specific. For example, typical values for the English language are (in words per minute) x-slow = 80, slow = 120, medium = between 180 and 200, fast = 500.
<percentage>
Only non-negative percentage values are allowed. This represents a change relative to the given keyword value (see enumeration above), or to the default value for the root element, or otherwise to the inherited speaking rate (which may itself be a combination of a keyword value and of a percentage, in which case percentages are combined multiplicatively). For example, 50% means that the speaking rate gets multiplied by 0.5 (half the value). Percentages above 100% result in faster speaking rates (relative to the base keyword), whereas percentages below 100% result in slower speaking rates.
Examples
1
<body>
2
<e1>
3
<e2>
4
<e3>
5
...
6
</e3>
7
</e2>
8
</e1>
9
</body>
01
body { voice-rate: inherit; } /* the initial value is 'normal'
02
(the actual speaking rate value
03
depends on the active voice) */
04
e1{ voice-rate: +50%; } /* the computed value is
05
['normal' and 50%], which will resolve
06
to the rate corresponding to 'normal'
07
multiplied by 0.5 (half the speaking rate) */
08
e2{ voice-rate: fast120%; } /* the computed value is
09
['fast' and 120%], which will resolve
10
to the rate corresponding to 'fast'
11
multiplied by 1.2 */
12
e3{ voice-rate: normal; /* "resets" the speaking rate to the intrinsic voice value,
13
the computed value is 'normal' (see comment below for actual value) */
14
voice-family: "another-voice"; } /* because the voice is different,
