CSS property: azimuth

Description

Audio direction.

Spatial audio is an important stylistic property for aural presentation. It provides a natural way to tell several voices apart, as in real life (people rarely all stand in the same spot in a room). Stereo speakers produce a lateral sound stage. Binaural headphones or the increasingly popular 5-speaker home theater setups can generate full surround sound, and multi-speaker setups can create a true three-dimensional sound stage. VRML 2.0 also includes spatial audio, which implies that in time consumer-priced spatial audio hardware will become more widely available.

This property is most likely to be implemented by mixing the same signal into different channels at differing volumes. It might also use phase shifting, digital delay, and other such techniques to provide the illusion of a sound stage. The precise means used to achieve this effect and the number of speakers used to do so are user agent-dependent; this property merely identifies the desired end result.

Syntax

azimuth: <angle>;

azimuth: <direction> [ behind ] | behind;

azimuth: leftwards;

azimuth: rightwards;

Values

<angle>

Position is described in terms of an angle within the range -360deg to 360deg. The value 0deg means directly ahead in the center of the sound stage. 90deg is to the right, 180deg behind, and 270deg (or, equivalently and more conveniently, -90deg) to the left.

<direction>
left-sideSame as 270deg. With behind, 270deg.
far-leftSame as 300deg. With behind, 240deg.
leftSame as 320deg. With behind, 220deg.
center-leftSame as 340deg. With behind, 200deg.
centerSame as 0deg. With behind, 180deg.
center-rightSame as 20deg. With behind, 160deg.
rightSame as 40deg. With behind, 140deg.
far-rightSame as 60deg. With behind, 120deg.
right-sideSame as 90deg. With behind, 90deg.
leftwards

Moves the sound to the left, relative to the current angle. More precisely, subtracts 20 degrees. Arithmetic is carried out modulo 360 degrees. Note that leftwards is more accurately described as "turned counter-clockwise," since it always subtracts 20 degrees, even if the inherited azimuth is already behind the listener (in which case the sound actually appears to move to the right).

rightwards

Moves the sound to the right, relative to the current angle. More precisely, adds 20 degrees. See leftwards for arithmetic.

Versions

Examples

h1 {
    azimuth: 30deg;
}
h1 {
    azimuth: far-right;
}
h1 {
    azimuth: far-right behind;
}
h1 {
    azimuth: behind;
}