CSS2 聽覺參考
聽覺樣式表
聽覺樣式表可把語音合成與音響效果相組合，使用戶可以聽到信息，而無需進(jìn)行閱讀。
聽覺呈現(xiàn)可用于：
- 視覺能力低弱的人士
- 幫助用戶學(xué)習(xí)閱讀
- 幫助有閱讀障礙的用戶
- 家庭娛樂
- 在汽車中使用
聽覺呈現(xiàn)通常會(huì)把文檔轉(zhuǎn)化為純文本，然后傳給屏幕閱讀器（可讀出屏幕上所有字符的一種程序）。
聽覺樣式表的一個(gè)例子：
h1, h2, h3, h4
{
voice-family: male;
richness: 80;
cue-before: url("beep.au")
}
上面的例子可以讓語音合成器演奏一段聲音，然后用男性的聲音讀出標(biāo)題。
CSS2 聽覺參考
W3C : "W3C" 列的數(shù)字顯示出屬性由哪個(gè) CSS 標(biāo)準(zhǔn)定義（CSS1 還是 CSS2）。
| 屬性 | 描述 | 值 | W3C |
|---|---|---|---|
| azimuth | Sets where the sound/voices should come from (horizontally) |
|
2 |
| cue | A shorthand property for setting the cue-before and cue-after properties in one declaration |
|
2 |
| cue-after | Specifies a sound to be played after speaking an element's content to delimit it from other |
|
2 |
| cue-before | Specifies a sound to be played before speaking an element's content to delimit it from other |
|
2 |
| elevation | Sets where the sound/voices should come from (vertically) |
|
2 |
| pause | A shorthand property for setting the pause-before and pause-after properties in one declaration |
|
2 |
| pause-after | Specifies a pause after speaking an element's content |
|
2 |
| pause-before | Specifies a pause before speaking an element's content |
|
2 |
| pitch | Specifies the speaking voice |
|
2 |
| pitch-range | Specifies the variation in the speaking voice. (Monotone voice or animated voice?) |
|
2 |
| play-during | Specifies a sound to be played while speaking an element's content |
|
2 |
| richness | Specifies the richness in the speaking voice. (Rich voice or thin voice?) |
|
2 |
| speak | Specifies whether content will render aurally |
|
2 |
| speak-header | Specifies how to handle table headers. Should the headers be spoken before every cell, or only before a cell with a different header than the previous cell |
|
2 |
| speak-numeral | Specifies how to speak numbers |
|
2 |
| speak-punctuation | Specifies how to speak punctuation characters |
|
2 |
| speech-rate | Specifies the speed of the speaking |
|
2 |
| stress | Specifies the "stress" in the speaking voice |
|
2 |
| voice-family | A prioritized list of voice family names that contain specific voices |
|
2 |
| volume | Specifies the volume of the speaking |
|
2 |