MediaTrackConstraints: volume property
Deprecated
Avoid using this feature in new projects. This feature may be a candidate for removal from web standards or browsers.
Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.
The MediaTrackConstraints dictionary's
volume property is a ConstrainDouble
describing the requested or mandatory constraints placed upon the value of the
volume constrainable property.
If needed, you can determine whether or not this constraint is supported by checking
the value of MediaTrackSupportedConstraints.volume as returned by a call
to MediaDevices.getSupportedConstraints(). However, typically this is
unnecessary since browsers will ignore any constraints they're unfamiliar with.
Value
A ConstrainDouble describing the acceptable or required value(s) for an
audio track's volume, on a linear scale where 0.0 means silence and 1.0 is the highest
supported volume.
If this value is a number, the user agent will attempt to obtain media whose volume is
as close as possible to this number given the capabilities of the hardware and the other
constraints specified. Otherwise, the value of this ConstrainDouble will
guide the user agent in its efforts to provide an exact match to the required volume (if
exact is specified or both min and max are
provided and have the same value) or to a best-possible value.
Any constraint set which only permits values outside the range 0.0 to 1.0 cannot be satisfied and will result in failure.
Examples
See the Constraint exerciser example.